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1.
BMC Oral Health ; 24(1): 208, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336661

RESUMO

BACKGROUND: Efficient utilization of residual bone volume and the prevention of inferior alveolar nerve injury are critical considerations in immediate implant placement (IIP) within the posterior mandibular region. Addressing these challenges, this study focuses on the clinical efficacy and implant accuracy of dynamic real-time navigation, an emerging technology designed to enhance precision in implantation procedures. METHODS: This study included 84 patients with 130 implants undergoing immediate placement in the posterior mandibular region. Stratified into dynamic navigation, static guide plate, and freehand implant groups, clinical indicators, including initial stability, distance to the inferior alveolar nerve canal, depth of implant placement, and various deviations, were systematically recorded. Statistical analysis, employing 1- or 2-way ANOVA and Student's t-test, allowed for a comprehensive evaluation of the efficacy of each technique. RESULTS: All 130 implants were successfully placed with an average torque of 22.53 ± 5.93 N.cm. In the navigation group, the distance to the inferior alveolar nerve and the depth of implant placement were significantly greater compared to the guide plate and freehand groups (P < 0.05). Implant deviation was significantly smaller in both the navigation and guide plate groups compared to the freehand group(P < 0.05). Additionally, the navigation group exhibited significantly reduced root and angle deviations compared to the guide plate group(P < 0.05), highlighting the superior precision of navigation-assisted immediate implant placement. CONCLUSIONS: It is more advantageous to use dynamic navigation rather than a static guide plate and free-hand implant insertion for immediate posterior mandibular implant implantation.


Assuntos
Implantes Dentários , Cirurgia Assistida por Computador , Humanos , Estudos Retrospectivos , Implantação Dentária Endóssea/métodos , Mandíbula/cirurgia , Tomografia Computadorizada de Feixe Cônico , Imageamento Tridimensional , Desenho Assistido por Computador
2.
J Environ Sci (China) ; 136: 451-459, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37923455

RESUMO

Large-scale metal contamination across the food web is an intractable problem due to increasing pollutant emissions, atmospheric transport, and dry and wet deposition of elements. The present study focus on several trace metals that are rarely studied but have special toxicity, including tin (Sn), antimony (Sb), gold (Au), hafnium (Hf), palladium (Pd), platinum (Pt), ruthenium (Ru), tellurium (Te) and iridium (Ir). We investigated trace metals residues and distribution characteristics, and further evaluated the potential health risks from major daily food intakes in 33 cities in China. Sn, Sb, Ir, Hf, and Au were frequently detected in food samples with the concentrations ranged from ND (not detected) to 24.78 µg/kg ww (wet weight). Eggs exhibited the highest residual level of all detected metals (13.70 ± 14.70 µg/kg ww in sum), while the lowest concentrations were observed in vegetables (0.53 ± 0.17 µg/kg ww in sum). Sn accounting for more than 50% of the total trace metals concentration in both terrestrial and aquatic animal origin foods. In terrestrial plant origin foods, Sn and Ir were the most abundant elements. Hf and Au were the most abundant elements in egg samples. In addition, Sb and Ir showed a clear trophic dilution effect in terrestrial environments, while in aquatic ecosystems, Sn, Hf, and Au exhibited obvious trophic amplification effects. The calculated average estimated daily intake (EDI) via food consumption in five regions of China was 0.09 µg/(kg·day), implying the health risk of aforementioned elements was acceptable.


Assuntos
Dieta , Ecossistema , Oligoelementos , Animais , Humanos , Dieta/efeitos adversos , População do Leste Asiático , Metais/análise , Medição de Risco , Oligoelementos/análise
3.
J Craniofac Surg ; 33(4): 1230-1235, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34907945

RESUMO

PURPOSE: Reduction of the bilateral zygomaticomaxillary complex (ZMC) fracture with individualized templates based on computer- aided surgical simulation system. To evaluate the practicality and accuracy of this approach in the treatment of bilateral ZMC fracture. METHODS: Sixteen patients with bilateral ZMC fractures were collected to create a study model. The authors reconstruct the ZMC on one side via the three-dimensional (3D) model, and then mirrored to the opposite side. Multiple individualized templates were made based on the 3D model, and used as intraoperative guidance to reduce fractures. After surgery, the facial symmetry and the position of zygoma were observed. The mouth opening, pupil level, and sensation of infraorbital nerve were evaluated. Some mark points on zygoma were measured and the postoperative horizontal asymmetry rate (H) was calculated. Besides, orbital height and width were measured. RESULTS: For all patients, the position of bilateral ZMC was basically restored. The patients with restriction of mouth opening all recovered to normal. The H values were less than 3.0% at all mark points. There was almost no difference in bilateral orbital width and height. Meanwhile, there was no significant difference between the preoperative measurements of the ideal virtual 3D model and the postoperative measurements of patients. CONCLUSIONS: The study proves that application of computer-aided design and individualized templates can accurately guide the reduction operation of ZMC fracture, restore the ideal shape of ZMC, and obtain good facial symmetry.


Assuntos
Fraturas Maxilares , Procedimentos de Cirurgia Plástica , Fraturas Zigomáticas , Desenho Assistido por Computador , Humanos , Fraturas Maxilares/diagnóstico por imagem , Fraturas Maxilares/cirurgia , Zigoma/cirurgia , Fraturas Zigomáticas/diagnóstico por imagem , Fraturas Zigomáticas/cirurgia
4.
J Environ Sci (China) ; 111: 51-60, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34949373

RESUMO

Water-insoluble organic compounds (WIOCs) are an important fraction of atmospheric fine particulate matters (PM2.5), which could affect the climate system and threaten human health potentially. In this study, molecular characterization of WIOCs in PM2.5 were investigated by 15 T Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) with atmospheric pressure photoionization (APPI) source in positive ion mode. A total of 2573 and 1875 molecular formulas were identified in WIOCs extracted by dichloromethane, which were collected in hazy and normal days, respectively. The identified molecular formulas were further classified into four major subgroups, including CH, CHN, CHO and CHNO compounds. CHO compounds predominated in WIOCs, accounting for more than 60% in both samples. CHNO compounds (26.6%) and CH compounds (16.1%) were the second highest subgroups in WIOCs from the hazy days and normal days, respectively. The relative abundance and number of nitro-substituted aromatic compounds were significantly higher in hazy days than in normal days. The molecular composition of WIOCs was more complex in hazy days while more aromatic compounds were identified in normal days.


Assuntos
Material Particulado , Água , Aerossóis/análise , Humanos , Espectrometria de Massas , Compostos Orgânicos
5.
Environ Sci Technol ; 55(19): 13122-13131, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34523920

RESUMO

Due to commercial uses and environmental degradation of aryl phosphate esters, diphenyl phosphate (DPhP) is frequently detected in environmental matrices and is thus of growing concern worldwide. However, information on potential adverse effects of chronic exposure to DPhP at environmentally realistic concentrations was lacking. Here, we investigated the effects of life cycle exposure to DPhP on zebrafish at environmentally relevant concentrations of 0.8, 3.9, or 35.6 µg/L and employed a dual-omics approach (metabolomics and transcriptomics) to characterize potential modes of action. Exposure to DPhP at 35.6 µg/L for 120 days resulted in significant reductions in body mass and length of male zebrafish, but did not cause those same effects to females. Predominant toxicological mechanisms, including inhibition of oxidative phosphorylation, down-regulation of fatty acid oxidation, and up-regulation of phosphatidylcholine degradation, were revealed by integrated dual-omics analysis and successfully linked to adverse outcomes. Activity of succinate dehydrogenase and protein content of carnitine O-palmitoyltransferase 1 were significantly decreased in livers of male fish exposed to DPhP, which further confirmed the proposed toxicological mechanisms. This study is the first to demonstrate that chronic, low-level exposure to DPhP can retard growth via inhibiting energy output in male zebrafish.


Assuntos
Retardadores de Chama , Peixe-Zebra , Animais , Compostos de Bifenilo , Metabolismo Energético , Feminino , Estágios do Ciclo de Vida , Masculino , Fosfatos
6.
Oral Dis ; 26(5): 876-884, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32031319

RESUMO

BACKGROUND: The study explored the potential function of astrocyte elevated gene-1 (AEG-1) on angiogenesis in tongue squamous cell carcinoma (TSCC) in TSCC cell lines. METHODS: The different degrees of angiogenesis were detected in TSCC cell lines expressing different levels of AEG-1 by chick chorioallantoic membrane (CAM) experimental model. Next, we established xenografts of different TSCC cell lines with different expression levels of AEG-1 in nude mice and conducted immunohistochemistry to evaluate the expression of the angiogenesis-associated factor, that is, vascular endothelial growth receptor factor 2 (VEGFR-2) and microvessel density (MVD). Vascular endothelial growth factor (VEGF) was detected by ELISA. RESULTS: CAM assay showed that the number of vessels was significantly reduced in AEG-1-down um1 cell line (p < .05), whereas the number was significantly increased in AEG-1-over um2 cell line (p < .05). Moreover, up-regulated AEG-1 expression level was associated with higher tumor angiogenesis, which was reflected by augmented expression levels of VEGF (p < .01), VEGFR-2 (p < .05), and MVD counting (p < .01). CONCLUSIONS: This study demonstrated that AEG-1 can promote tumor angiogenesis in TSCC and inhibition of tumor angiogenesis by repressing the expression of AEG-1 may be a novel potential treatment approach for TSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Proteínas de Membrana , Proteínas de Ligação a RNA , Neoplasias da Língua , Animais , Astrócitos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Nus , Prognóstico , Proteínas de Ligação a RNA/fisiologia , Neoplasias da Língua/tratamento farmacológico , Neoplasias da Língua/genética , Fator A de Crescimento do Endotélio Vascular
7.
J Oral Pathol Med ; 48(6): 459-467, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30955218

RESUMO

BACKGROUND: The aim of this study was to ascertain the expression and role of FMNL3 in tongue squamous cell carcinoma (TSCC) tissues. MATERIALS AND METHODS: Immunohistochemistry, qRT-PCR, and western blot were used to study the expression of FMNL3 in TSCC tissues and its adjacent normal tissues. The relationship between FMNL3 overexpression and various clinicopathological parameters and patients' survival were further assessed. Next, we applied SCC25 and UM1 cell lines to study the effect of FMNL3 on tumor cell proliferation, migration, and invasion by silencing FMNL3. RESULTS: In this study, we demonstrated that FMNL3 expression was notably upregulated in TSCC tissues and associated with poor prognosis. The Cox regression survival analyses identified FMNL3 as an important independent predictor for patients' overall survival. We found that FMNL3 silencing by siRNA inhibited SCC25 and UM1 cell migration an invasion. CONCLUSION: FMNL3 overexpression is related to the metastasis of TSCC and poor prognosis. High expression of FMNL3 may become a new potential prognostic biomarker for patients with TSCC.


Assuntos
Carcinoma de Células Escamosas/patologia , Forminas/genética , Neoplasias da Língua/patologia , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Neoplasias da Língua/genética
8.
Ecotoxicol Environ Saf ; 181: 164-171, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31185430

RESUMO

Short-chain chlorinated paraffins (SCCPs) are frequently detected in environmental matrices and human tissues. It was hypothesized that SCCPs might interact with the peroxisome proliferator-activated receptor α (PPARα). In the present study, an in vitro, dual-luciferase reporter gene assay and in silico molecular docking analysis were employed together to study the interactions between SCCPs congeners and PPARα. Expressions of genes downstream in pathways activated by PPARα in liver of rats exposed to 1, 10, or 100 mg/kg bm/d of C10-13-CPs (56.5% Cl) for 28 days were examined to confirm activation potencies of SCCPs toward PPARα signaling. Effects of exposure to C10-13-CPs (56.5% Cl) on fatty acid metabolism in rat liver were also explored via a pseudo-targeted metabolomics strategy. Our results showed that C10-13-CPs (56.5% Cl) caused a dose-dependent greater expression of luciferase activity of rat PPARα. Molecular docking modeling revealed that SCCPs had a strong capacity to bind with PPARα only through hydrophobic interactions and the binding affinity was dependent on the degree of chlorination in SCCPs congeners. In livers of male rats, exposure to 100 mg/kg bm/d of C10-13-CPs (56.5% Cl) resulted in up-regulated expressions of 11 genes that are downstream in the PPARα-activated pathway and regulate catabolism of fatty acid. Consistently, accelerated fatty acid oxidation was observed mainly characterized by lesser concentrations of ∑fatty acids in livers of rats. Overall, these results demonstrated, for the first time, that SCCPs could activate rat PPARα signaling and thereby disrupt metabolism of fatty acid in livers of male rats.


Assuntos
Ácidos Graxos/metabolismo , Fígado/efeitos dos fármacos , PPAR alfa/metabolismo , Parafina/toxicidade , Animais , Expressão Gênica/efeitos dos fármacos , Genes Reporter , Halogenação , Fígado/metabolismo , Luciferases/genética , Masculino , Simulação de Acoplamento Molecular , PPAR alfa/química , Parafina/química , Ratos , Transdução de Sinais , Regulação para Cima
9.
Environ Sci Technol ; 52(15): 8173-8182, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30016592

RESUMO

Haze is a serious pollution problem during the wintertime in North China. In this study, we investigated how the periodic cycle of winter haze events affect the environmental behaviors of two typical persistent organic pollutants, namely, polychlorinated dibenzo- p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated diphenyl ethers (PBDEs), in the atmosphere of a typical megacity, Beijing. The average atmospheric concentrations of the total di- to octa-CDD/Fs (∑PCDD/Fs: 378.0 pg/m3) and the total mono- to nona-BDEs (∑9hPBDEs: 166.5 pg/m3) during haze episodes increased by 3.6-fold and 1.9-fold compared with those during the nonhaze periods, respectively; and their concentrations both linearly increased with PM2.5 levels and decreased as a power function of the atmospheric boundary layer height. The elevated concentrations could be clearly attributed to the vertically sinking motion of airflow in the midlower troposphere. When a haze event occurred, the partitioning rate of PCDD/Fs and PBDEs into particles was reduced; the largest fraction of the particle-bound ∑PCDD/Fs was shifted from ultrafine particles to accumulation mode particles; and a steady-state model (Li-Ma-Yang model) satisfactorily described the gas-particle partitioning of the PCDD/F and PBDE homologues. The inhalation exposure risk evaluation indicated that special attention should be paid to the increased cancer risk induced by the elevated inhalation intake of PCDD/Fs during haze episodes.


Assuntos
Poluentes Atmosféricos , Benzofuranos , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Atmosfera , Pequim , China , Dibenzofuranos , Dibenzofuranos Policlorados , Monitoramento Ambiental , Éteres Difenil Halogenados , Tempo (Meteorologia)
10.
Environ Sci Technol ; 50(6): 3145-53, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26876804

RESUMO

The toxic effects of hexabromocyclododecane (HBCD) are complex, and the underlying toxicological mechanisms are still not completely understood. In this study, a pseudotargeted metabolomic approach based on the UHPLC/Q-Trap MS system was developed to assess the HBCD-intervention-related metabolic alteration in HepG2 cells. In addition, some physiologic indicators and relevant enzyme activities were measured. HBCD exposure obviously impaired metabolic homeostasis and induced oxidative stress, even at an environmentally relevant dose (0.05 mg/L). Metabolic profiling and multivariate analysis indicated that the main metabolic pathways perturbed by HBCD included amino acid metabolism, protein biosynthesis, fatty acid metabolism, and phospholipid metabolism. HBCD suppressed the cell uptake of amino acids, mainly through inhibition of the activity of membrane transport protein Na(+)/K(+)-ATPase. HBCD down-regulated glycolysis and ß-oxidation of long-chain fatty acids, causing a large decrease of ATP production. As a result, the across-membrane transport of amino acids was further inhibited. Meanwhile, HBCD induced a significant increase of total phospholipids, mainly through the remodeling of phospholipids from the increased free fatty acids. The obtained metabolomic results also provided some new evidence and clues regarding the toxicological mechanisms of HBCD that contribute to obesity, diabetes, nervous system damage, and developmental disorders.


Assuntos
Hidrocarbonetos Bromados/toxicidade , Metabolômica/métodos , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/metabolismo , Retardadores de Chama/toxicidade , Células Hep G2 , Homeostase/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Espectrometria de Massas/métodos , Redes e Vias Metabólicas , Metabolômica/instrumentação , Obesidade/induzido quimicamente , Obesidade/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfolipídeos/metabolismo
11.
J Environ Sci (China) ; 48: 209-217, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27745666

RESUMO

Hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA) are two kinds of brominated flame retardants and widely present in the environment and biota. The levels, spatial distributions and mass inventories of HBCD and TBBPA were investigated in sediments and paddy soils from the Liaohe River Basin in northeast China. The concentrations of ΣHBCD and TBBPA were in the range of not detected (nd) to 4.02ng/g dry weight (dw) and 0.03 to 4.06ng/g dw, respectively. γ-HBCD was dominated in sediments, while the abundance of α-HBCD was relatively high in paddy soils. The spatial distributions of HBCD and TBBPA in surface sediments and paddy soils indicated that the local point-input was their major source. The significant correlation between total organic carbon (TOC) contents and the HBCD levels suggested that TOC content also exerted an influence on the distribution of HBCD in sediments. Meanwhile, it was found that the irrigation with river water was not the major transportation pathway of HBCD and TBBPA in paddy soils. Based on the study, it was estimated that there were about 1.67tons HBCD and 2.20tons TBBPA deposited into sediments of the Liaohe River system every year. The total mass inventories of HBCD and TBBPA in sediments were far higher than that in paddy soils.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Bromados/análise , Bifenil Polibromatos/análise , Poluentes Químicos da Água/análise , Agricultura , China , Ecossistema , Retardadores de Chama/análise , Sedimentos Geológicos/química , Oryza , Solo/química
12.
Environ Sci Technol ; 49(5): 3076-83, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25660998

RESUMO

Short-chain chlorinated paraffins (SCCPs) have attracted considerable attention for their characteristic of persistent organic pollutants. However, very limited information is available for their toxic effects at environmentally relevant doses, limiting the evaluation of their health risks. In this study, cell viability assay and targeted metabolomic approach was used to evaluate the environmental dose (<100 µg/L) effect of SCCPs on HepG2 cells. Cell viability was found to be decreased with increases in exposure dose of SCCPs. Exposure for 48 h to C10-CPs resulted in a significant reduction in cell viability compared with 24 h, even at 1 µg/L. SCCPs exposure altered the intracellular redox status and caused significant metabolic disruptions. As a kind of peroxisome proliferator, SCCPs specifically stimulated the ß-oxidation of unsaturated fatty acids and long-chain fatty acids. Meanwhile, SCCPs exposure disturbed glycolysis and amino acid metabolism, and led to the up-regulation of glutamate metabolism and urea cycle. The toxic effects of SCCPs might mainly involve the perturbation of energy production, protein biosynthesis, fatty acid metabolism, and ammonia recycling.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Hidrocarbonetos Clorados/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Parafina/toxicidade , Células Hep G2 , Humanos , Redes e Vias Metabólicas/efeitos dos fármacos
13.
J Stomatol Oral Maxillofac Surg ; : 101976, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39043292

RESUMO

OBJECTIVE: To evaluate the accuracy of the implant accuracy and clinical effect of navigation-assisted immediate implant placement (IIP) in the posterior maxillary tooth region. METHODS: This study included 60 patients with 96 implants undergoing IIP in the posterior maxillary region from January 2021 to December 2022, stratified into dynamic navigation and freehand implant groups. All clinical indicators, including initial stability, implant deviation (entry point deviation, end point deviation, depth deviation and angle deviation), marginal bone resorption and implant success rate, were systematically recorded. RESULTS: All implants were successfully placed with an average torque of (24.38 ± 1.84)N.cm. The mean entry point deviation, apex point deviation and angular deviation in the navigation group were significantly smaller than that of the freehand group (P < 0.05). Marginal bone resorption was significantly less in the navigated group than in the freehand group (P < 0.05). All dental implants were considered an operational success and the mean follow-up time was (27.8 ± 8.4) months. CONCLUSION: The application of dynamic navigation-assisted immediate implant placement in the maxillary posterior region can achieve good implant accuracy and satisfactory clinical results.

14.
Sci Total Environ ; 922: 171393, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38431175

RESUMO

N,N'-substituted p-phenylenediamines (PPDs) are widely used antioxidants in rubber tires, which could be released and accumulated in road dusts with rubber tires wear. As ozonation product of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), 6PPD-quinone (6PPD-Q) exhibited higher toxicity to coho salmon. However, studies on their environmental behaviors are still limited. Road dust is the major medium PPDs exist, which significantly affects the levels of PPDs in other mediums, especially surface water and particulate matter. In this study, road dust samples were collected in 55 major cities of China to explore the distribution characteristics of PPDs and 6PPD-Q. The concentrations of total PPDs (ΣPPDs) and 6PPD-Q in urban trunk road dust samples were in the ranges of 7.90-727 and 3.00-349 ng/g, with median concentrations of 68 and 49 ng/g, respectively. 6PPD and 6PPD-Q are the dominant components in most road dusts. The functional region-dependent pollution characteristics of PPDs and 6PPD-Q give the first finding that urban tunnel road was the highly polluted region, followed by urban trunk roads. Suburban road dusts had a lower pollution level. Moreover, the estimated daily intake (EDI) of PPDs and 6PPD-Q for children was much higher than adults.


Assuntos
Monitoramento Ambiental , Borracha , Adulto , Criança , Humanos , Antioxidantes , Poeira/análise , Quinonas
15.
J Hazard Mater ; 477: 135335, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39079292

RESUMO

Chlorinated paraffins (CPs) are chlorinated alkane mixtures widely used as flame retardants and plasticizers in multiple industrial products. Systematic research on how homolog-specific properties affect their atmospheric behaviors is limited. Herein, we investigated the levels of short-chain CPs (SCCPs) and medium-chain CPs (MCCPs) in long-timescale, seasonal, and size-fractioned particles in the urban area of Dalian, a coastal city in northern China. The average SCCP and MCCP concentrations in particles with diameters ≤ 10 µm were 3.36 and 4.89 ng/m3, respectively, and a general increase in the SCCP concentration was observed from 2.59 ng/m3 in 2018 - 2019 to 7.84 ng/m3 in 2021 - 2023. CP levels and patterns showed significant seasonal variation, with a higher abundance of C11-13Cl7-9 in winter and C10-12Cl5 in summer. Elevated particle levels in winter and high temperatures in summer contributed to the seasonal variations. SCCPs and MCCPs were concentrated on particles with diameters of < 1 µm and their geometric mean diameter increased with the increasing carbon and chlorine numbers. Total Daily intake of SCCP and MCCP was calculated to be 0.15 and 0.22 ng/kg bw/day for adults. 53.1 %, 8.5 %, and 38.4 % of inhaled SCCPs, and 60.6 %, 7.6 %, and 31.8 % of inhaled MCCPs deposited into the head airway, tracheobronchial region, and alveolar region, respectively. This study reports on how homolog-specific physicochemical properties alter the temporal variations, size distributions, and inhaled fractions of CPs.

16.
Sci Total Environ ; 945: 173993, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38879026

RESUMO

A total of 17 groups of wastewaters from the chemical industrial parks and matched receiving river waters were collected in the east of China. The measured total concentrations of 21 analyzed PFAS analogues (∑21PFAS) in the influents and effluents of the wastewater treatment plants (WWTPs) were in the range of 0.172-20.6 µg/L (mean: 18.2 µg/L, median: 3.9 µg/L) and 0.167-93.6 µg/L (mean: 10.8 µg/L, median: 1.12 µg/L), respectively, which were significantly higher than those observed in the upstream (range: 0.0158-7.05 µg/L, mean: 1.09 µg/L, median: 0.482 µg/L) and downstream (range: 0.0237-1.82 µg/L, mean: 0.697 µg/L, median: 0.774 µg/L) receiving waters. Despite the concentrations and composition profiles of PFAS varied in the water samples from different sampling sites, PFOA was generally the major PFAS analogue in the research areas, mainly due to the history of PFOA production and usage as well as the specific exemptions. The calculated concentration ratios of the short-chain PFCAs and PFSAs to their respective predecessors (PFOA and PFOS) in most of the samples far exceeded 1, indicating a shift from legacy PFOA and PFOS to short-chain PFAS in the research areas. Correlation network analysis and the calculated concentration ratios of PFAS in the effluents versus influents indicated transformation may have occurred during the water treatment processes and PFAS could not be efficiently removed in the WWTPs. Wastewater discharge of chemical industrial parks is a vital source of PFAS dispersed into the aquatic environment.

17.
Water Res ; 250: 121076, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38171178

RESUMO

Rapid urbanization accelerates the release of anthropogenic heavy metals from local to wider water systems, posing a serious threat to aquatic ecosystems and public health. The characteristics of trace elements were investigated to evaluate the environmental status of surface water in 40 cities of China. The concentrations of 22 elements in surface water ranged from 7.00 × 10-4 to 4.37 × 105 µg/L. The water quality can be classified as "excellent" except Songhuajiang. The levels of As, Cd, Cr, Pb, and Hg are all within the limits permitted by national drinking water quality standards. An obvious regional distribution characteristic was observed, with concentrations of Zn, Mn, Ni, Cu, Co, U, and Cr higher in surface water collected in the north than in the south, while the trends for Cd, Tl, and As are opposite. Notably, Tl shows significant geographical divergences, with the level of surface water collected from the south nine times higher than that from the north. The regional distribution of the mineral, industrial, or agricultural activity might be responsible for the south-to-north difference of these elements. The hazard index (HI) and total cancer risk (TCR) through oral or dermal contact with water-related heavy metals were further calculated. The average HI was 0.54 in the north and 0.29 in the south for adults, while HI for children was relatively higher. The value was 1.01 and 0.55 in the north and south, respectively. TCR in the north is 2.58 × 10-4 and mainly contributed by Cr (88.1 %), while TCR in the south is 4.48 × 10-5 and mainly contributed by As (98.4 %). The research results can provide essential data for effective water resources management and human health protection in China.


Assuntos
Metais Pesados , Oligoelementos , Criança , Adulto , Humanos , Monitoramento Ambiental/métodos , Oligoelementos/análise , Ecossistema , Cádmio , Medição de Risco , Metais Pesados/análise , China , Receptores de Antígenos de Linfócitos T
18.
Sci Total Environ ; 933: 173150, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38735312

RESUMO

The intensive and widespread application of pesticides in agroecosystems can lead to the simultaneous exposure of non-target aquatic organisms to insecticides and herbicides. However, the underlying mechanisms through which aquatic organisms undergo metabolic reprogramming to withstand the combined effects of the insecticide imidacloprid (IMI) and herbicide sulfentrazone (SUL) remain poorly elucidated. This study employs metabolomics to investigate the effects of individual and combined exposures to IMI and SUL on zebrafish (Danio rerio), aiming to simulate complex environmental conditions. Metabolomics analysis revealed extensive metabolic reprogramming in larvae induced by the selected agrochemicals. Both individual and combined exposures disrupted nucleotide metabolism, inhibited glycolysis, and led to the accumulation of acetylcholine through the shared modulation of differential metabolites. Notably, individual exposure exhibited a unique mode of action. Larvae exposed to IMI alone showed mitochondrial dysfunction, potentially stemming from interference with the electron transport chain, while SUL-induced disruptions were associated with glycerophospholipid accumulation, marking it as a critical target. Additionally, calculations of the metabolic effect level index indicated antagonistic interactions between SUL and IMI mixtures at an overall metabolic level. The results obtained through investigating the lethal and sub-lethal effects also revealed that the simultaneous application of SUL and IMI may have the potential to diminish acute and developmental toxicity in zebrafish. This study underscores the significance of metabolomics as a valuable and effective strategy for deciphering the toxicity and interactions of agrochemical mixtures.


Assuntos
Inseticidas , Larva , Neonicotinoides , Nitrocompostos , Poluentes Químicos da Água , Peixe-Zebra , Animais , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Larva/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Inseticidas/toxicidade , Herbicidas/toxicidade , Metabolômica
19.
Se Pu ; 42(2): 176-184, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38374598

RESUMO

Short-chain chlorinated paraffins (SCCPs) are an emerging class of persistent organic pollutants (POPs) that are widely detected in environmental matrices and human samples. Because of their environmental persistence, long-range transport potential, bioaccumulation potential, and biotoxicity, SCCPs pose a significant threat to human health. In this study, metabolomics technology was applied to reveal the metabolomic interference in human normal hepatic (L02) cells after exposure to low (1 µg/L), moderate (10 µg/L), and high (100 µg/L) doses of SCCPs. Principal component analysis (PCA) and metabolic effect level index (MELI) values showed that all three SCCP doses caused notable metabolic perturbations in L02 cells. A total of 72 metabolites that were annotated by MS/MS and matched with the experimental spectra in the Human Metabolome Database (HMDB) or validated by commercially available standards were selected as differential metabolites (DMs) across all groups. The low-dose exposure group shared 33 and 36 DMs with the moderate- and high-dose exposure groups, respectively. The moderate-dose exposure group shared 46 DMs with the high-dose exposure group. In addition, 33 DMs were shared among the three exposure groups. Among the 72 DMs, 9, 9, and 45 metabolites participated in the amino acid, nucleotide, and lipid metabolism pathways, respectively. The results of pathway enrichment analysis showed that the most relevant metabolic pathways affected by SCCPs were the lipid metabolism, fatty acid ß-oxidation, and nucleotide metabolism pathways, and that compared with low-dose exposure, moderate- and high-dose SCCP exposures caused more notable perturbations of these metabolic pathways in L02 cells. Exposure to SCCPs perturbed glycerophospholipid and sphingolipid metabolism. Significant alterations in the levels of phosphatidylcholines, phosphatidylethanolamines, and sphingomyelins indicated SCCP-induced biomembrane damage. SCCPs inhibited fatty acid ß-oxidation by decreasing the levels of short- and medium-chain acylcarnitines in L02 cells, indicating that the energy supplied by fatty acid oxidation was reduced in these cells. Furthermore, compared with low- and moderate-dose SCCPs, high-dose SCCPs produced a significantly stronger inhibition of fatty acid ß-oxidation. In addition, SCCPs perturbed nucleotide metabolism. The higher hypoxanthine levels observed in L02 cells after SCCP exposures indicate that SCCPs may induce several adverse effects, including hypoxia, reactive oxygen species production, and mutagenesis in L02 cells.


Assuntos
Hidrocarbonetos Clorados , Parafina , Humanos , Parafina/toxicidade , Parafina/análise , Espectrometria de Massas em Tandem , Hidrocarbonetos Clorados/toxicidade , Hidrocarbonetos Clorados/análise , Monitoramento Ambiental/métodos , Ácidos Graxos , Nucleotídeos , Hepatócitos/química , China
20.
Sci Total Environ ; 912: 168515, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37977390

RESUMO

The trace elements present in breast milk play a vital role in the growth and development of infants. Nevertheless, numerous studies have reported the presence of toxic metal contamination in breast milk from various countries and regions, which poses potential risks to breastfed infants. This article aimed to investigate the characteristics of trace elements in breast milk and explore the relationship between breast milk and diet in Dalian, a coastal city in northeastern China. Breast milk samples and representative local food samples were collected from Dalian for research. The results revealed that 57 % of breast milk samples significantly exceeded the WHO safety limit (0.6 µg/L) for arsenic, with a measured mean value of 0.96 µg/L. Moreover, the levels of chromium (mean value: 2.63 µg/L) in 34 % of breast milk samples exceed the WHO recommended safety level (chromium: 1.5 µg/L). Aquatic foods accounted for 60 % to 90 % of the total intake of arsenic, cadmium, vanadium, mercury, and lead. The Spearman correlation analysis demonstrated strong positive correlations among breast milk metal elements, including copper-zinc (r = 0.68) and nickel­chromium (r = 0.89). Furthermore, the food-to-milk accumulation factors (FMAF) of strontium, nickel, arsenic, vanadium, cadmium, and mercury were relatively low (median values <0.005). While the FMAF values for chromium and lead were higher, with median values of 0.038 and 0.07, respectively. The results indicated potential risks of the toxic metal arsenic in breast milk from Dalian, China for breastfed infants. Therefore, continuous monitoring of breast milk for toxic metals and foodborne contamination is necessary.


Assuntos
Intoxicação por Arsênico , Arsênio , Mercúrio , Metais Pesados , Oligoelementos , Lactente , Feminino , Humanos , Cádmio/análise , Arsênio/análise , Leite Humano/química , Níquel/análise , Oligoelementos/análise , Vanádio/análise , Mercúrio/análise , Cromo/análise , Intoxicação por Metais Pesados , Ingestão de Alimentos , Metais Pesados/análise
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