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1.
Sci Total Environ ; 932: 172987, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38734084

ABSTRACT

Liquid crystal monomers (LCMs) are emerging contaminants characterized by their persistence, bioaccumulation potential, and toxicity. They have been observed in several environmental matrices associated with electronic waste (e-waste) dismantling activities, particularly in China. However, there is currently no information on the pollution caused by LCMs in other developing countries, such as Pakistan. In this study, we collected soil samples (n = 59) from e-waste dismantling areas with different functions in Pakistan for quantification analysis of 52 target LCMs. Thirty out of 52 LCMs were detected in the soil samples, with the concentrations ranging from 2.14 to 191 ng/g (median: 16.3 ng/g), suggesting widespread contamination by these emerging contaminants. Fluorinated LCMs (median: 10.4 ng/g, range: 1.27-116 ng/g) were frequently detected and their levels were significantly (P < 0.05) higher than those of non-fluorinated LCMs (median: 6.11 ng/g, range: not detected (ND)-76.7 ng/g). The concentrations and profiles of the observed LCMs in the soil samples from the four functional areas varied. The informal dismantling of e-waste poses a potential exposure risk to adults and infants, with median estimated daily intake (EDI, ng/kg bw/day) values of 0.0420 and 0.1013, respectively. Calculation of the hazard quotient (HQ) suggested that some LCMs (e.g., ETFMBC (1.374) and EDFPB (1.257)) may pose potential health risks to occupational workers and their families. Considering the widespread contamination and risks associated with LCMs, we strongly recommend enhancing e-waste management and regulation in Pakistan.


Subject(s)
Electronic Waste , Environmental Monitoring , Liquid Crystals , Soil Pollutants , Pakistan , Electronic Waste/analysis , Environmental Monitoring/methods , Soil Pollutants/analysis , Humans , Environmental Exposure/statistics & numerical data , Risk Assessment
2.
Environ Int ; 186: 108609, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38579452

ABSTRACT

Recently, evidence of aromatic amine antioxidants (AAs) existence in the dust of the electronic waste (e-waste) dismantling area has been exposed. However, there are limited studies investigating occupational exposure and toxicity associated with AAs and their transformation products (p-phenylenediamines-quinones, i.e., PPD-Qs). In this study, 115 dust and 42 hand wipe samples collected from an e-waste recycling industrial park in central China were analyzed for 19 AAs and 6 PPD-Qs. Notably, the median concentration of ∑6PPD-Qs (1,110 ng/g and 1,970 ng/m2) was significantly higher (p < 0.05, Mann-Whitney U test) than that of ∑6PPDs (147 ng/g and 34.0 ng/m2) in dust and hand wipes. Among the detected analytes, 4-phenylaminodiphenylamine quinone (DPPD-Q) (median: 781 ng/g) and 1,4-Bis(2-naphthylamino) benzene quinone (DNPD-Q) (median: 156 ng/g), were particularly prominent, which were first detected in the e-waste dismantling area. Occupational exposure assessments and nuclear receptor interference ability, conducted through estimated daily intake (EDI) and molecular docking analysis, respectively, indicated significant occupational exposure to PPD-Qs and suggested prioritized Liver X receptors (LXRs) disruption potential of PPDs and PPD-Qs. The study provides the first evidence of considerable levels of AAs and PPD-Qs in the e-waste-related hand wipe samples and underscores the importance of assessing occupational exposure and associated toxicity effects.


Subject(s)
Antioxidants , Dust , Electronic Waste , Occupational Exposure , Recycling , Occupational Exposure/analysis , Humans , Dust/analysis , China , Quinones/analysis , Amines/analysis
3.
Eco Environ Health ; 2(3): 131-141, 2023 Sep.
Article in English | MEDLINE | ID: mdl-38074986

ABSTRACT

Liquid crystal monomers (LCMs) are a family of synthetic organic chemicals applied in the liquid crystal displays (LCDs) of various electric and electronic products (e-products). Due to their unique properties (i.e., persistence, bioaccumulative potential, and toxicity) and widespread environmental distributions, LCMs have attracted increasing attention across the world. Recent studies have focused on the source, distribution, fate, and toxicity of LCMs; however, a comprehensive review is scarce. Herein, we highlighted the persistence and bioaccumulation potential of LCMs by reviewing their physical-chemical properties. The naming rules were suggested to standardize the abbreviations regarding LCMs. The sources and occurrences of LCMs in different environmental compartments, including dust, sediment, soil, leachate, air and particulate, human serum, and biota samples, were reviewed. It is concluded that the LCMs in the environment mainly originate from the usage and disassembly of e-products with LCDs. Moreover, the review of the potential recycling and removal technologies regarding LCMs from waste LCD panels suggests that a combination of natural attenuation and physic-chemical remediation should be developed for LCMs remediations in the future. By reviewing the health risks and toxicity of LCMs, it is found that a large gap exists in their toxicity and risk to organisms. The fate and toxicity investigation of LCMs, and further investigations on the effects on the human exposure risks of LCMs to residents, especially to occupational workers, should be considered in the future.

4.
Environ Sci Technol ; 57(11): 4454-4463, 2023 03 21.
Article in English | MEDLINE | ID: mdl-36867107

ABSTRACT

Liquid crystal monomers (LCMs) are indispensable materials in liquid crystal displays, which have been recognized as emerging persistent, bioaccumulative, and toxic organic pollutants. Occupational and nonoccupational exposure risk assessment suggested that dermal exposure is the primary exposure route for LCMs. However, the bioavailability and possible mechanisms of dermal exposure to LCMs via skin absorption and penetration remain unclear. Herein, we used EpiKutis 3D-Human Skin Equivalents (3D-HSE) to quantitatively assess the percutaneous penetration of nine LCMs, which were detected in e-waste dismantling workers' hand wipes with high detection frequencies. LCMs with higher log Kow and greater molecular weight (MW) were more difficult to penetrate through the skin. Molecular docking results showed that ABCG2 (an efflux transporter) may be responsible for percutaneous penetration of LCMs. These results suggest that passive diffusion and active efflux transport may be involved in the penetration of LCMs across the skin barrier. Furthermore, the occupational dermal exposure risks evaluated based on the dermal absorption factor suggested the underestimation of the continuous LCMs' health risks via dermal previously.


Subject(s)
Liquid Crystals , Occupational Exposure , Humans , Skin Absorption , Molecular Docking Simulation , Skin/chemistry , Skin/metabolism , Occupational Exposure/analysis
5.
BMC Cardiovasc Disord ; 23(1): 18, 2023 01 13.
Article in English | MEDLINE | ID: mdl-36639616

ABSTRACT

BACKGROUND: Early exercise for acute deep venous thrombosis (DVT) improves the patient's symptoms and does not increase the risk of pulmonary embolism. However, information about its effect on thrombus resolution is limited. The aim of this study was to investigate the role of resistance exercise (RE) in thrombus resolution and recanalization and determine its underlying mechanisms.  METHODS: Ninety-six C57BL/6 J mice were randomly divided into four groups: Control group (C, n = 24); DVT group (D, n = 24); RE + DVT group (ED, n = 24); and inhibitor + RE + DVT group (IED, n = 24). A DVT model was induced by stenosis of the inferior vena cava (IVC). After undergoing IVC ultrasound within 24 h post-operation to confirm DVT formation, mice without thrombosis were excluded. Other mice were sacrificed and specimens were obtained 14 or 28 days after operation. Thrombus-containing IVC was weighed, and the thrombus area and recanalization rate were calculated using HE staining. Masson's trichrome staining was used to analyze the collagen content. RT-PCR and ELISA were performed to examine IL-6, TNF-α, IL-10, and VEGF expression levels. SIRT1 expression was assessed using immunohistochemistry staining and RT-PCR. VEGF-A protein expression and CD-31-positive microvascular density (MVD) in the thrombus were observed using immunohistochemistry.  RESULTS: RE did not increase the incidence of pulmonary embolism. It reduced the weight and size of the thrombus and the collagen content. Conversely, it increased the recanalization rate. It also decreased the levels of the pro-inflammatory factors IL-6 and TNF-α and increased the expression levels of the anti-inflammatory factor IL-10. RE enhanced VEGF and SIRT1 expression levels and increased the MVD in the thrombosis area. After EX527 (SIRT1 inhibitor) was applied, the positive effects of exercise were suppressed. CONCLUSIONS: RE can inhibit inflammatory responses, reduce collagen deposition, and increase angiogenesis in DVT mice, thereby promoting thrombus resolution and recanalization. Its underlying mechanism may be associated with the upregulation of SIRT1 expression.


Subject(s)
Physical Conditioning, Animal , Pulmonary Embolism , Resistance Training , Venous Thrombosis , Animals , Humans , Mice , Collagen/metabolism , Disease Models, Animal , Interleukin-10 , Interleukin-6/metabolism , Mice, Inbred C57BL , Pulmonary Embolism/complications , Sirtuin 1/genetics , Sirtuin 1/metabolism , Tumor Necrosis Factor-alpha/metabolism , Up-Regulation , Vascular Endothelial Growth Factor A/metabolism , Venous Thrombosis/diagnostic imaging , Venous Thrombosis/therapy , Venous Thrombosis/etiology
6.
Environ Int ; 169: 107535, 2022 11.
Article in English | MEDLINE | ID: mdl-36152360

ABSTRACT

Liquid crystal monomers (LCMs) are widely used chemicals and ubiquitous emerging organic pollutants in the environment, some of which have persistent, bio-accumulative, and toxic potentials. Elevated levels of LCMs have been found in the e-waste dismantling associated areas. However, information on their internal exposure bio-monitoring is scarce. For the first time, occurrences of LCMs were observed in the serum samples of occupational workers (n = 85) from an e-waste dismantling area in South China. Twenty-nine LCMs were detected in serum samples of the workers, with a median value of 35.2 ng/mL (range: 7.78-276 ng/mL). Eight noticed LCMs were found to have relatively high detection frequencies ranging from 52.9% to 96.5%. The correlation analysis of individual LCMs indicated potential common applications and similar sources to the LCMs in occupational workers. Fluorinated LCMs were identified as the predominant monomers in the workers. Additionally, the estimated daily intake of the LCMs in the occupational workers was significantly higher than those in residents from the reference areas (p < 0.05, Mann-Whitney U Test, median values: 1.46 ng/kg bw/day versus 0.40 ng/kg bw/day), indicating a substantially higher exposure level to e-waste dismantling workers.


Subject(s)
Electronic Waste , Environmental Pollutants , Liquid Crystals , China , Environmental Monitoring , Humans
7.
Environ Int ; 164: 107295, 2022 06.
Article in English | MEDLINE | ID: mdl-35580435

ABSTRACT

Liquid crystal monomers (LCMs) are a class of emerging, persistent, bioaccumulative, and toxic organic pollutants. They are detected in various environmental matrixes that are associated with electronic waste (e-waste) dismantling. However, their occurrence and distribution in indoor and outdoor dust on a national scale remain unknown. In this study, a dedicated target analysis quantified a broad range of 60 LCMs in dust samples collected across China. The LCMs were frequently detected in indoor (n = 48) and outdoor dust (n = 97; 37 sampled concomitantly with indoors dust) from dwellings, and indoor dust from cybercafés (n = 34) and phone repair stores (n = 22), with median concentrations of 41.6, 94.7, 106, and 171 ng/g, respectively. No significant spatial difference was observed for the concentrations of the total LCMs among distinct geographical regions (p > 0.05). The median daily intake values of the total LCMs via dust ingestion, dermal contact, and inhalation were estimated at 1.50 × 10-2, 2.90 × 10-2, and 8.57 × 10-6 ng/kg BW/day for adults and 1.47 × 10-1, 1.22 × 10-1, and 2.18 × 10-5 ng/kg BW/day for children, respectively. These estimates suggested higher exposure risks for children and indicated that dust ingestion and dermal contact significantly contribute to the human intake of LCMs. The microenvironmental pollution levels of LCMs together with the potential exposure risks associated with some of these chemicals are of concern for human health.


Subject(s)
Air Pollution, Indoor , Electronic Waste , Environmental Pollutants , Liquid Crystals , Adult , Air Pollution, Indoor/analysis , Child , China , Dust/analysis , Electronic Waste/analysis , Environmental Exposure/analysis , Environmental Pollutants/analysis , Humans
8.
Comput Intell Neurosci ; 2021: 7077556, 2021.
Article in English | MEDLINE | ID: mdl-34956355

ABSTRACT

The smart museum is a new platform for the appreciation and display of cultural relics across time and space. In the era of 3D scanning technology, computer technology, and network technology, it is necessary to deeply study the smarter and more perfect forms of smart museums. This article, through the analysis of the characteristics of the display level of the smart museum, tries to create a new humanized and intelligent display of cultural relics.


Subject(s)
Museums
9.
J Nanobiotechnology ; 19(1): 237, 2021 Aug 11.
Article in English | MEDLINE | ID: mdl-34380475

ABSTRACT

BACKGROUND: During wound healing, the overproduction of reactive oxygen species (ROS) can break the cellular oxidant/antioxidant balance, which prolongs healing. The wound dressings targeting the mitigation of ROS will be of great advantages for the wound healing. puerarin (PUE) and ferulic acid (FA) are natural compounds derived from herbs that exhibit multiple pharmacological activities, such as antioxidant and anti-inflammatory effects. Polydopamine (PDA) is made from natural dopamine and shows excellent antioxidant function. Therefore, the combination of natural antioxidants into hydrogel dressing is a promising therapy for wound healing. RESULTS: Hydrogel wound dressings have been developed by incorporating PUE or FA via PDA nanoparticles (NPs) into polyethylene glycol diacrylate (PEG-DA) hydrogel. This hydrogel can load natural antioxidant drugs and retain the drug in the gel network for a long period due to the presence of PDA NPs. Under oxidative stress, this hydrogel can improve the activity of superoxide dismutase and glutathione peroxidase and reduce the levels of ROS and malondialdehyde, thus preventing oxidative damage to cells, and then promoting wound healing, tissue regeneration, and collagen accumulation. CONCLUSION: Overall, this triple antioxidant hydrogel accelerates wound healing by alleviating oxidative injury. Our study thus provides a new way about co-delivery of multiple antioxidant natural molecules from herbs via antioxidant nanoparticles for wound healing and skin regeneration.


Subject(s)
Antioxidants/pharmacology , Coumaric Acids/pharmacology , Hydrogels/pharmacology , Indoles/pharmacology , Isoflavones/pharmacology , Polymers/pharmacology , Wound Healing/drug effects , Animals , Antioxidants/chemistry , Bandages , Coumaric Acids/chemistry , Drug Liberation , Humans , Hydrogels/chemistry , Indoles/chemistry , Isoflavones/chemistry , Mice , Nanoparticles/chemistry , Periodontal Ligament , Polyethylene Glycols , Polymers/chemistry , Reactive Oxygen Species , Skin/drug effects , Stem Cells
10.
Biomater Sci ; 7(10): 4230-4236, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31393463

ABSTRACT

Oxidative damage generated by various biochemical pathways can disrupt the oxidant/antioxidant balance in cells, causing slow wound healing and tissue regeneration; in this regard, a hydrogel dressing with antioxidant properties can promote wound healing; however, its design is still a challenge. Herein, a polydopamine/puerarin (PDA/PUE) nanoparticle-incorporated polyethylene glycol diacrylate hybrid hydrogel (PEG-DA/PDA/PUE) with antioxidant properties was prepared and used as a wound-healing material. Experimental observations indicated that the PEG-DA/PDA/PUE hydrogel possessed excellent swelling capacity and mechanical property. Moreover, the antioxidant capability was enhanced with an increase in the concentration of polydopamine/puerarin nanoparticles in the hydrogel. The hydrogel presented good cell proliferation and antioxidant activity, including a decrease in ROS and increase in the superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity under oxidative stress conditions. Furthermore, the full-thickness skin-defect-regeneration process could be accelerated via the antioxidant hydrogel treatment. This study validated the potential applications of an antioxidant hydrogel for wound healing.


Subject(s)
Antioxidants/administration & dosage , Biocompatible Materials/administration & dosage , Hydrogels/administration & dosage , Indoles/administration & dosage , Isoflavones/administration & dosage , Nanoparticles/administration & dosage , Polymers/administration & dosage , Wound Healing/drug effects , Animals , Cell Proliferation/drug effects , Cells, Cultured , Dental Pulp/cytology , Male , Periodontal Ligament/cytology , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Stem Cells/drug effects
11.
Curr Drug Metab ; 19(9): 750-758, 2018.
Article in English | MEDLINE | ID: mdl-29749307

ABSTRACT

BACKGROUND: For safe and effective therapy, drugs are supposed to be actively targeted at the desired disease locations. As a promising candidate for drug delivery, long circulating system with various strategies has been widely used. Recently, biomimetic strategies mediated long circulation of drug delivery system have been increasingly developed for forming various nanoparticles and shown the anticipated potential. METHOD: In this review, a variety of approaches for long circulation strategy have been surveyed, together with different modifications. The future perspectives as well as challenges in this field are also discussed. RESULTS: Amounts of papers from nearly 5 years were included in the review, this review identified PEGylation, liposomal, biomimetic materials were the effective strategy for drug long circulation. CONCLUSION: The findings of this review confirm the importance of long circulation for drug delivery. Designing of a delivery system requires an appropriate balance between the stability of material and the long term circulation in body, which can be tailored to a specific application, based on experience optimization and customized design. Biomimetic design strategy is likely to revolutionize the current medical condition. In the medical field, using these emerging technologies on materials is promising to improving the traditional modalities and achieving novel applications on long circulation of delivery systems.


Subject(s)
Drug Delivery Systems , Animals , Humans , Pharmaceutical Preparations/administration & dosage , Pharmaceutical Preparations/chemistry , Pharmaceutical Preparations/metabolism
12.
J Mater Chem B ; 6(42): 6723-6730, 2018 Nov 14.
Article in English | MEDLINE | ID: mdl-32254689

ABSTRACT

Transdermal drug delivery is an attractive, non-invasive treatment. It can avoid first-pass hepatic metabolism and provides the possibility of self-administration. Hydrogels are promising biomaterials due to their important qualities such as biocompatibility and biodegradability. Recently, there has been tremendous growth in the area of hydrogels for transdermal drug delivery. In this work, a new kind of arginine-based poly(ester amide) (Arg-PEA) and polyethylene glycol diacrylamide (PEG-DA) hybrid hydrogel was developed for transdermal drug delivery. The hydrogels not only possess excellent swelling capacity, but also have good mechanical properties, which were then evaluated as drug delivery agents using insulin as a model system. Cytotoxicity testing and in vivo skin irritation tests demonstrated that the hydrogels were biocompatible. Finally, the results indicated that the prepared hydrogels could not only perform transdermal drug delivery, but also might regulate blood glucose levels in a mouse model with streptozotocin-induced diabetes.

13.
Glycoconj J ; 34(2): 207-217, 2017 04.
Article in English | MEDLINE | ID: mdl-27975161

ABSTRACT

The present study aimed to characterize the glucan from C. mollissima Blume fruits and its selenium derivative, then investigate their antitumor activity in vitro. A glucan, designated as CPA, was firstly isolated from the fruits of C. mollissima Blume. Structure analysis indicated that CPA was a linear 1,6-α-D-glucan with the average molecular weight about 2.0 × 103 kDa. The selenylation modification derivative of CPA (sCPA), exhibited a stronger antiproliferative effect on tumor cells than CPA in vitro. CPA and sCPA could induce HeLa cells apoptosis and decrease mitochondrial membrane potential. sCPA could also arrest HeLa cells in S phase, promote reactive oxygen species generation and activate caspase-3 activity in HeLa cells. These results manifest that CPA and sCPA inhibit the proliferation of HeLa cells via different mechanisms, which is meaningful for their potential use as antitumor drugs.


Subject(s)
Antineoplastic Agents, Phytogenic , Fagaceae/chemistry , Flowers/chemistry , Glucans , Neoplasms/drug therapy , Selenium , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Caspase 3/metabolism , Glucans/chemistry , Glucans/isolation & purification , Glucans/pharmacology , HeLa Cells , Humans , MCF-7 Cells , Neoplasm Proteins/metabolism , Neoplasms/metabolism , Selenium/chemistry , Selenium/pharmacology
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