Publications by authors named "Mei Sun"

420 Publications

Ecological rice-cropping systems mitigate global warming - A meta-analysis.

Sci Total Environ 2021 May 24;789:147900. Epub 2021 May 24.

College of Resources and Environment, Hunan Agricultural University, Changsha 410125, China. Electronic address:

Ecological rice-cropping systems (ERSs) are prosperous rice ecosystems that have a profound influence on global greenhouse (GHG) effects. However, the high variation in research results requires an accurate evaluation of the ERS effects. In this study, three typical ERS modes, rice-crayfish, rice-duck, and rice-fish were selected, and a meta-analysis was conducted using the data of 34 studies to comprehensively evaluate the effects of ERSs on GHG emissions, the global warming potential (GWP), and GHG intensity (GHGI). The results showed that the ERSs reduced CH4 emissions significantly (-12.5%), but increased N2O emissions by 11.3% as compared with traditional rice-cropping systems (TRSs). Further, ERSs have slightly lower GWP, rice yield, and GHGI values (6.5%, 5.5%, and 5.6%, respectively) than TRSs. The rice-crayfish and rice-duck modes significantly alleviated the GWP by 18.0% and 11.1%, respectively, whereas the rice-fish mode enhanced the GWP by 20.8%. Moreover, the rice-duck mode significantly reduced the GHGI by 17.2%, while the ricecrayfish and rice-fish modes increased the GHGI by 9.7% and 8.8%, respectively. Further, the ERSs significantly changed the dissolved oxygen concentration in the flood water as well as the Eh, dissolved organic carbon, and ammonium nitrogen in the soil, wherein the effect sizes of the ERSs on the GHG emissions were significantly correlated with their respective increase. Considering the net ecosystem economic budget and CO2 emissions equivalent/output, ERSs were found to be effective "green technologies". Further, we found that the rice-duck ERS was a good ecological ricecropping system for global warming mitigation. Our study provided new ideas for sustainable agriculture.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147900DOI Listing
May 2021

The role of autophagy in hepatic fibrosis.

Authors:
Mei Sun Li Tan Min Hu

Am J Transl Res 2021 15;13(6):5747-5757. Epub 2021 Jun 15.

Department of Laboratory Medicine, The Second Xiangya Hospital, Central South University Changsha 410011, Hunan, China.

Hepatic fibrosis is a chronic liver injury process, and its continuous development can lead to cirrhosis, hepatic failure and even hepatocellular carcinoma (HCC). Autophagy has attracted much attention because of its controversial role in the course of hepatic fibrosis. In this review, we introduce the mechanism related to noncoding RNAs and some of the signaling pathways that promote or inhibit fibrosis by affecting autophagy. Finally, we list some targets related to autophagy that enable hepatic fibrosis therapy and forecast its prospect in hepatic fibrosis. This review will provide new ideas in diagnosing and treating hepatic fibrosis, which will be helpful to reduce the incidence of cirrhosis and its complications.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8290830PMC
June 2021

The combined toxicity of ultra-small SiO nanoparticles and bisphenol A (BPA) in the development of zebrafish.

Comp Biochem Physiol C Toxicol Pharmacol 2021 Jul 1;248:109125. Epub 2021 Jul 1.

Institute of Nanochemistry and Nanobiology, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China. Electronic address:

The complex combined effects of nanoparticles and environmental pollutants in the aqueous environment will inevitably affect aquatic ecosystem and human life. Bisphenol A (BPA) is listed as a typical kind of endocrine disruptors, there is little research about the joint toxicity of co-exposure of SiO nanoparticles (NPs) and BPA. In this study, fluorescent ultra-small SiO NPs (US-FMSNs) around 6.3 nm were synthesized and investigated for their combined effects with BPA on zebrafish during the early developmental stages within 4-168 h post fertilization (hpf). The results showed that US-FMSNs could accumulate in the chorion, abdomen and intestine in zebrafish. In addition, the different concentration (0.1, 1, 10 μg/mL) of BPA and US-FMSNs (200 μg/mL) demonstrated strong impact on multiple toxic endpoints at four periods (72, 96, 120, 168 hpf). We found US-FMSNs had no significant toxic effect on zebrafish, while BPA (10 μg/mL) showed a degree of developmental toxicity. Compared with single BPA (10 μg/mL) exposure, combined exposure enhanced the developmental toxicity of zebrafish, including increased mortality, decreased hatching rate and body length, and decreased activity of total superoxide dismutase (T-SOD) and increased malondialdehyde (MDA) levels. Our results indicated that US-FMSNs and BPA induced oxidative stress, and the effect of the co-exposure was less than that of single exposure (10 μg/mL). This study hereby provides a basis for the potential ecological and health risks of SiO NPs and BPA exposure.
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http://dx.doi.org/10.1016/j.cbpc.2021.109125DOI Listing
July 2021

Clinical Characteristics of Paediatric Pancreatitis Caused by Pancreaticobiliary Malformation: A Single-Centre Retrospective Analysis.

Front Pediatr 2021 10;9:677894. Epub 2021 Jun 10.

Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang, China.

To investigate the clinical profiles of children with pancreatitis caused by pancreaticobiliary malformation. We retrospectively analysed the clinical data of children diagnosed with pancreatitis at our institute from June 2017 to January 2021. A total of 195 patients and 169 control subjects were included in this study. Twenty-six (13.3%) patients had pancreaticobiliary malformation-related pancreatitis. The average age of onset in the pancreaticobiliary malformation pancreatitis (PMP) group was lower than that in the non-PMP group, and the difference was statistically significant. The number of patients in the PMP group that had jaundice was significantly higher than that of the non-PMP group ( < 0.05). Logistic regression analysis showed that total bilirubin (TB) and γ-glutamyltransferase (GGT) (odds ratio = 1.096, < 0.01) were independent predictors of pancreaticobiliary malformation-related pancreatitis in children. The positive detection rate of pancreaticobiliary malformation was 68% for abdominal ultrasound, 38.4% for abdominal enhanced computed tomography, and 91.3% for magnetic resonance cholangiopancreatography (MRCP). The recurrence rate (34.6%) in the PMP group was higher than that in the non-PMP group (15.4%, < 0.05); surgical therapy had the lowest recurrence rate. Age at initial onset of pancreatitis was younger and the period to recurrence was shorter in the PMP group than in the non-PMP group ( < 0.05). Pancreaticobiliary malformation is one of the major causes of paediatric pancreatitis. Elevated TB and GGT in patients with pancreatitis may be suggestive for underlying pancreaticobiliary malformation not solely to pancreatitis. MRCP should be used when pancreatitis due to pancreaticobiliary malformation is suspected. Surgery or endoscopic retrograde cholangiopancreatography-guided intervention may be helpful but further study is needed.
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http://dx.doi.org/10.3389/fped.2021.677894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8222541PMC
June 2021

The correlation between the vitamin A, D, and E levels and recurrent respiratory tract infections in children of different ages.

Am J Transl Res 2021 15;13(5):5665-5671. Epub 2021 May 15.

Cangzhou Central Hospital Cangzhou, Hebei, China.

Objective: To investigate the correlation between the vitamin A, D, and E levels and recurrent respiratory tract infections (RRTIs) in children of different ages.

Methods: A total of 150 RRTI patients were divided into three groups: the 0 to 2 year-old group, the 3-5 year-old group, and the 6-14 year-old group. Collectively, we refer to the three groups as the RRTI group. The serum vitamin A, D and E levels were measured in the three groups. Healthy children without RRTIs were recruited as a control group. The correlations between the changes in the vitamin A, D, and E levels and the RRTIs were analyzed.

Results: The vitamin A, D, and E levels decreased significantly in the children with RRTIs, but only the vitamin A and D levels were negatively correlated with the incidence of RRTIs, while the vitamin E levels were not significantly correlated with the incidence of RRTIs. The follow-up results showed that the serum vitamin A, D, and E levels in the RRTI group were significantly increased after the treatment, and the WBC and CRP levels were remarkably reduced.

Conclusion: Monitoring the serum vitamin A and D levels helps determine the disease severity, and the supplementation of adequate vitamin A and D through diet or drugs is of great help in treating RRTIs.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8205845PMC
May 2021

Postpartum depression and family function in Chinese women within 1 year after childbirth: A cross-sectional study.

Res Nurs Health 2021 Aug 8;44(4):633-642. Epub 2021 Jun 8.

Department of Community Nursing, Xiangya School of Nursing, Central South University, Changsha, China.

Family-related factors are reported to influence the development of postpartum depression (PPD), but limited studies have considered the role of family function in this condition. This study aimed to describe the proportion of people with probable or suspected PPD and to determine the relationships among PPD, family function, and obstetric factors. A cross-sectional study was conducted with 630 women who attended six integrated teaching and scientific research communities in Changsha, China. Instruments included the Edinburgh Postpartum Depression Scale and the Family Assessment Device (FAD). A multivariate logistic regression model was used to determine the risk factors of PPD. The prevalence of probable or suspected PPD was 37% in this sample. We found communication (odds ratio [OR] = 3.795, 95% confidence interval [CI] = 1.619-8.897), affective responsiveness (OR = 2.685, 95% CI = 1.642-4.301), role (OR = 2.483, 95% CI = 1.041-5.922), and general functioning (OR = 5.704,95% CI = 2.233-14.569) dimensions of FAD, and type of feeding (OR = 2.700, 95% CI = 1.285-5.671) influenced PPD in the context of Chinese culture. To decrease the prevalence of PPD, interventions such as health education programs and cognitive behavior therapy to strengthen family function are recommended among couples during and after pregnancy.
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http://dx.doi.org/10.1002/nur.22159DOI Listing
August 2021

Potential economic indicators and environmental quality in African economies: new insight from cross-sectional autoregressive distributed lag approach.

Environ Sci Pollut Res Int 2021 Jun 2. Epub 2021 Jun 2.

Department of Economics, Obafemi Awolowo University, Ile-Ife, Nigeria.

Growing economic development and substantial demographic shifts may have a momentous consequence on environmental quality in a number of African countries. Consequently, this recent study offers the opportunity to explore the nexus among unobserved influential economic indicators and environmental quality (measured through CO emissions) in a panel of 26 African economies spanning from 1990 to 2018. The aggregated panel is sub-classified into net exporters (NEC) and net importers (NIC) of embodied carbon. Considering existence of cross-section reliance and heterogeneity issues, all observed series are preliminarily confirmed stationary and cointegrated. Further, key outcomes from the common correlated effect Pooled Mean Group (CCEPMG) estimator through cross-sectional autoregressive distributed lag (CSARDL) approach showed that (i) economic growth and fossil fuel energy use stimulate environmental degradation among all panels, (ii) urbanization and trade openness enhance environmental quality in NEC panel while environmental damage is increased in NIC and aggregated panels, (iii) financial development also enhanced environmental quality in the totaled and NEC panel of African countries, but rather maturated climate deterioration in NIC panel, (iv) industrialization had a substantial adverse effect on environmental quality through surge in emission of CO concerning the aggregated panel and NEC African states, and (v) overall the environmental Kuznets curve (EKC) conjuncture is validated among all panels. The findings were also affirmed by Augmented Mean Group (AMG) technique. Finally, Dumitrescu-Hurlin Granger causality checks showed strong causal affiliations heterogeneously across all panels. From the policy perspective, the analytical outcomes from this study summarily encourage the introduction of profitable policies that can facilitate green energy and economic structural change to diminish the degree of environmental degradation from emission of CO. Steps to strengthen a low-carbon and sustainable green environment should therefore collectively address these factors during policy growth.
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http://dx.doi.org/10.1007/s11356-021-14598-8DOI Listing
June 2021

Health System Barriers and Facilitators to Delivering Additional Vaccines through the National Immunisation Programme in China: A Qualitative Study of Provider and Service-User Perspectives.

Vaccines (Basel) 2021 May 8;9(5). Epub 2021 May 8.

Department of Global Health and Development, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK.

In China, there are two categories of vaccines available from the Chinese Center for Disease Control and associated public health agencies. Extended Program of Immunization (EPI) vaccines are government-funded and non-EPI vaccines are voluntary and paid for out-of-pocket. The government plans to transition some non-EPI vaccines to EPI in the coming years, which may burden public health system capacity, particularly in terms of budget, workforce, supply chains, and information systems. Our study explored vaccinator and caregiver perspectives on introducing non-EPI vaccines into routine immunization and perceived facilitators and barriers affecting this transition. We conducted a qualitative study from a realist perspective, analysing semi-structured interviews with 26 vaccination providers and 160 caregivers in three provinces, selected to represent regional socioeconomic disparities across Eastern, Central, and Western China. Data were analysed thematically, using deductive and inductive coding. Most participants were positive about adding vaccines to the national schedule. Candidate EPI vaccines most frequently recommended by participants were varicella, mumps vaccine, and hand-foot-mouth disease. Providers generally considered existing workspaces, cold-chain equipment, and funding sufficient, but described frontline staffing and vaccine information systems as requiring improvement. This is the first qualitative study to explore interest, barriers, and facilitators related to adding vaccines to China's national schedule from provider and caregiver perspectives. Findings can inform government efforts to introduce additional vaccines, by including efforts to retain and recruit vaccine programme staff and implement whole-process data management and health information systems that allow unified nationwide data collection and sharing.
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http://dx.doi.org/10.3390/vaccines9050476DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8151436PMC
May 2021

Impaired right and left ventricular function and relaxation induced by pulmonary regurgitation are not reversed by tardive antifibrosis treatment.

Am J Physiol Heart Circ Physiol 2021 Jul 28;321(1):H38-H51. Epub 2021 May 28.

Division of Cardiology, Labatt Family Heart Centre, Hospital for Sick Children, Toronto, Ontario, Canada.

Pulmonary regurgitation (PR) after repair of tetralogy of Fallot (rTOF) is associated with progressive right (RV) and left (LV) ventricular dysfunction and fibrosis. However, angiotensin II receptor blockade therapy has shown mixed and often disappointing results. The aim of this study was to serially assess changes in biventricular remodeling, dysfunction, and interactions in a rat model of isolated severe PR and to study the effects of angiotensin II receptor blockade. PR was induced in Sprague-Dawley rats by leaflet laceration. Shams ( = 6) were compared with PR ( = 5) and PR + losartan treatment ( = 6). In the treatment group, oral losartan (50 mg·kg·day) was started 6 wk after PR induction and continued for 6 wk until the terminal experiment. In all groups, serial echocardiography was performed every 2 wk until the terminal experiment where biventricular myocardium was harvested and analyzed for fibrosis. PR and PR + losartan rats experienced early progressive RV dilatation by 2 wk which then stabilized. RV systolic dysfunction occurred from 4 wk after insult and gradually progressed. In PR rats, RV dilatation caused diastolic LV compression and impaired relaxation. PR rats developed increased RV fibrosis compared with shams. Although losartan decreased RV fibrosis, RV dilatation and dysfunction were not improved. This suggests that RV dilatation is an early consequence of PR and affects LV relaxation. RV dysfunction may progress independent of further remodeling. Reduced RV fibrosis was not associated with improved RV function and may not be a viable therapeutic target in rTOF with predominant RV volume loading. The time-course of RV dilatation and the mechanisms of biventricular dysfunction caused by PR have not been well characterized and the effect of losartan in volume-overloaded RV remains controversial. Our findings suggest that severe PR induces early onset of RV dilatation and dysfunction with little progression after the first 4 wk. The RV dilatation distorts LV geometry with associated impaired LV relaxation. Losartan reduced RV fibrosis but did not reverse RV dilatation and dysfunction.
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http://dx.doi.org/10.1152/ajpheart.00467.2020DOI Listing
July 2021

[Effective components of Shengxian Decoction and its mechanism of action in treating chronic heart failure based on UHPLC-Q-TOF-MS integrated with network pharmacology].

Zhongguo Zhong Yao Za Zhi 2021 May;46(10):2489-2500

Department of Pharmacy, Changzheng Hospital, Second Military Medical University Shanghai 200003, China Institute of Chinese Materia Madica, Shanghai University of Traditional Chinese Medicine Shanghai 201203, China.

This study aimed to elucidate the effective components of Shengxian Decoction and its mechanism of action in treating chronic heart failure. Firstly, UHPLC-Q-TOF-MS was established to identify the main chemical constituents in the rat serum after intragastric administration with Shengxian Decoction. Secondly, the absorbed components in serum were then used for the network pharmacology analysis to infer the mechanism and effective components. Targets for constituents in serum were predicted at TCMSP and Swiss-TargetPrediction database. An association network map was drawn by network visualization software Cytoscape 3.6.1. Finally, GO enrichment analysis and KEGG pathway enrichment analysis were carried out for the core target genes. By UHPLC-Q-TOF-MS, 18 prototype compounds were definitely identified, including five compounds from Astragali Radix, four compounds from Anemarrhenae Rhizoma, four compounds from Bupleuri Radix, four compounds from Cimicifugae Rhizoma, and one compound from Platycodonis Radix. Those components of Shengxian Decoction were closely associated with 13 key protein targets, including inflammatory factors, like IL6, IL1 B, TNF, PTGS2, IL10; redox enzymes CAT, HMOX1, and MPO; cardiovascular targets, like VEGFA, NOS3, and NOS2; and transmememial proteins CAV1 and INS. Network pharmacology analysis showed that the 18 compounds could be responsible for the treatment of chronic heart failure by regulating HIF-1 signaling pathways, PI3 K-Akt signaling pathways, cGMP-PKG signaling pathways, cAMP signaling pathways and TNF signaling pathways. This study provided a scientific basis for mechanism and effective ingredients of Shengxian Decoction.
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http://dx.doi.org/10.19540/j.cnki.cjcmm.20200915.201DOI Listing
May 2021

High-Performance Room-Temperature UV-IR Photodetector Based on the InAs Nanosheet and Its Wavelength- and Intensity-Dependent Negative Photoconductivity.

ACS Appl Mater Interfaces 2021 Jun 25;13(22):26187-26195. Epub 2021 May 25.

Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing 100871, China.

Low-dimensional narrow-band-gap III-V semiconductors have great potential in high-performance electronics, photonics, and quantum devices. However, high-performance nanoscale infrared photodetectors based on isolated two-dimensional (2D) III-V compound semiconductors are still rare. In this work, we demonstrate a new type of photodetector based on the InAs nanosheet. The photodetector has high optoelectronic response in the ultraviolet-infrared band (325-2100 nm) at room temperature. The high-performance photodetector has very high responsivity (∼1231 A/W), EQE (2.2 × 10 %), and detectivity (5.46 × 10 Jones) to 700 nm light at low operating voltage (∼0.1 V). These results indicate that 2D InAs nanosheet devices have great potential in nano-optoelectronic devices and integrated optoelectronic devices. In addition, we observe for the first time that the InAs nanosheet devices have a negative photoconductivity (NPC) that is not only affected by the wavelength but also related to the optical power intensity of the light. After analyzing experimental data, we propose that the origin of the NPC may come from electron trapping, and two competing mechanisms of optical absorption and the photogating effect in the photoelectric response process cause the dependence on the light wavelength and optical power intensity.
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http://dx.doi.org/10.1021/acsami.1c05226DOI Listing
June 2021

Emissions, degradation and impact of HFO-1234ze from China PU foam industry.

Sci Total Environ 2021 Aug 20;780:146631. Epub 2021 Mar 20.

State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China. Electronic address:

Currently used foam agent HCFC-141b was undergoing phased out worldwide with the implementation of the Montreal Protocol. HFO-1234ze was proposed as replacement in polyurethane (PU) foam industry with shorter atmospheric lifetime. This paper calculated historical and future emissions of HCFC-141b and HFO-1234ze till 2050, used GEOS-Chem under two HFO-1234ze emission scenarios to track its atmospheric process and distribution, and to assess its potential environmental effects. Results showed that annual HCFC-141b emissions for 2015, 2019 and 2050 were 12.6 Gg/yr, 21.0 Gg/yr and 7.6 Gg/yr, respectively and emissions of HFO-1234ze would reach 124.4 Gg/yr by 2050. Under Scenario I with HFO-1234ze emissions of 12.6 Gg/yr as input, annual mixing ratios of HFO-1234ze and its products CFCHO and HCOF were 10.47, 2.68 and 1.74 pptv for China, and were 0.55, 0.18 and 0.1 pptv globally, respectively, suggesting the regional aggregation of these substances in emission areas. HCOF were removed from atmosphere by depositions, with total deposition rates of 22.06 g km y in CH, and 1.15 g km y in globe. Under Scenario II with HFO-1234ze emissions of 124.4 Gg/yr as input, annual mixing ratios of HFO-1234ze, CF3CHO and HCOF, along with HCOF total deposition rates were 102.98 26.36 and 17.17 pptv and 217 g km y in China, respectively, increased linearly to HFO-1234ze emissions change. The mixing ratios of HFO-1234ze and HCOF were too small to exert significant effects on current atmosphere burden and circulation, while CFCHO might potentially involve in aminolysis reaction under future emissions of HFO-1234ze.
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http://dx.doi.org/10.1016/j.scitotenv.2021.146631DOI Listing
August 2021

Near-Quantitative Defluorination of Perfluorinated and Fluorotelomer Carboxylates and Sulfonates with Integrated Oxidation and Reduction.

Environ Sci Technol 2021 05 5;55(10):7052-7062. Epub 2021 May 5.

Department of Chemical & Environmental Engineering, University of California, Riverside, California 92521, United States.

The UV-sulfite reductive treatment using hydrated electrons () is a promising technology for destroying perfluorocarboxylates (PFCAs, CFCOO) in any chain length. However, the C-H bonds formed in the transformation products strengthen the residual C-F bonds and thus prevent complete defluorination. Reductive treatments of fluorotelomer carboxylates (FTCAs, CF-CHCH-COO) and sulfonates (FTSAs, CF-CHCH-SO) are also sluggish because the ethylene linker separates the fluoroalkyl chain from the end functional group. In this work, we used oxidation () with hydroxyl radicals (HO•) to convert FTCAs and FTSAs to a mixture of PFCAs. This process also cleaved 35-95% of C-F bonds depending on the fluoroalkyl chain length. We probed the stoichiometry and mechanism for the oxidative defluorination of fluorotelomers. The subsequent reduction () with UV-sulfite achieved deep defluorination of the PFCA mixture for up to 90%. The following use of HO• to oxidize the H-rich residues led to the cleavage of the remaining C-F bonds. We examined the efficacy of integrated oxidative and reductive treatment of n = 1-8 PFCAs, n = 4,6,8 perfluorosulfonates (PFSAs, CF-SO), n = 1-8 FTCAs, and n = 4,6,8 FTSAs. A majority of structures yielded near-quantitative overall defluorination (97-103%), except for n = 7,8 fluorotelomers (85-89%), n = 4 PFSA (94%), and n = 4 FTSA (93%). The results show the feasibility of complete defluorination of legacy PFAS pollutants and will advance both remediation technology design and water sample analysis.
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http://dx.doi.org/10.1021/acs.est.1c00353DOI Listing
May 2021

Seasonal discrepancies in peroxyacetyl nitrate (PAN) and its correlation with ozone and PM: Effects of regional transport from circumjacent industrial cities.

Sci Total Environ 2021 Sep 24;785:147303. Epub 2021 Apr 24.

Research Institute of Environmental Science, College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China.

Peroxyacetyl nitrate (PAN) is the most important reservoir of nitrogen oxides, with effects on atmospheric oxidation capacity and regional nitrogen distribution. The first yearlong observational study of PAN was conducted from September 2018 to August 2019 at a suburban site and an urban site in Zhengzhou, Henan Province, central China. Compared with studies over the past two decades, summer PAN pollution at the suburban site and winter PAN pollution at both sites were more significant, with annual average concentrations of 1.96 ± 1.44 and 2.01 ± 1.59 ppbv, respectively. Seasonal PAN discrepancies between the urban and suburban areas were analyzed in detail. Active PAN formation, regional transport, photochemical precursors, and PAN lifetime played key roles during seasons with elevated PAN (winter and spring). According to the results of cluster analysis and potential source contribution function analysis, during the cold months, short-distance air mass transport from the east, south, and southeast of Henan Province and southern Hebei Province increased PAN pollution in urban Zhengzhou. PAN source areas were located in circumjacent industrial cities surrounding Zhengzhou except in the northeastern direction. Based on the relationships between pollutant concentrations, wind speed, and wind direction, a strong positive correlation between PAN and PM (and O) existed in winter due to their joint transport. A slow-moving, low-height air mass passed through surrounding industrial cities before reaching the study area, carrying both pollutants and leading to strong consistency between PAN and O levels. The long-term PAN characteristics described in this study will help clarify the causes of regional air pollution in inland city agglomerations. Moreover, the PAN correlations and joint transport of PAN and PM (or O) support the use of PAN as an indicator of air pollution introduced from surrounding industrial areas.
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http://dx.doi.org/10.1016/j.scitotenv.2021.147303DOI Listing
September 2021

The studies on wet chemical etching via in situ liquid cell TEM.

Ultramicroscopy 2021 Apr 6:113271. Epub 2021 Apr 6.

Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing 100871, China. Electronic address:

Wet chemical etching is a widely used process to fabricate fascinating nanomaterials, such as nanoparticles with precisely controlled size and shape. Understanding the etching mechanism and kinetic evolution process is crucial for controlling wet chemical etching. The development of in situ liquid cell transmission electron microscopy (LCTEM) enables the study on wet chemical etching with high temporal and spatial resolutions. However, there still lack a detailed literature review on the wet chemical etching studies by in situ LCTEM. In this review, we summarize the studies on wet etching nanoparticles, one-dimensional nanomaterials and nanoribbons by in situ LCTEM, including etching rate, anisotropic etching, morphology evolution process, and etching mechanism. The challenges and opportunities of in situ LCTEM are also discussed.
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http://dx.doi.org/10.1016/j.ultramic.2021.113271DOI Listing
April 2021

Molecular Characterization of the Oncogene BTF3 and Its Targets in Colorectal Cancer.

Front Cell Dev Biol 2020 11;8:601502. Epub 2021 Feb 11.

Department of Colorectal Surgery, Changhai Hospital, Shanghai, China.

Colorectal cancer (CRC) is one of the most commonly diagnosed and leading causes of cancer mortality worldwide, and the prognosis of patients with CRC remains unsatisfactory. Basic transcription factor 3 (BTF3) is an oncogene and hazardous prognosticator in CRC. Although two distinct functional mechanisms of BTF3 in different cancer types have been reported, its role in CRC is still unclear. In this study, we aimed to molecularly characterize the oncogene BTF3 and its targets in CRC. Here, we first identified the transcriptional targets of BTF3 by applying combined RNA-Seq and ChIP-Seq analysis, identifying CHD1L as a transcriptional target of BTF3. Thereafter, we conducted immunoprecipitation (IP)-MS and E3 ubiquitin ligase analysis to identify potential interacting targets of BTF3 as a subunit of the nascent-polypeptide-associated complex (NAC). The analysis revealed that BTF3 might also inhibit E3 ubiquitin ligase HERC2-mediated p53 degradation. Finally, miRNAs targeting BTF3 were predicted and validated. Decreased miR-497-5p expression is responsible for higher levels of BTF3 post-transcriptionally. Collectively, we concluded that BTF3 is an oncogene, and there may exist a transcription factor and NAC-related proteolysis mechanism in CRC. This study provides a comprehensive basis for understanding the oncogenic mechanisms of BTF3 in CRC.
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http://dx.doi.org/10.3389/fcell.2020.601502DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7905040PMC
February 2021

Decision Support for Tactical Combat Casualty Care Using Machine Learning to Detect Shock.

Mil Med 2021 01;186(Suppl 1):273-280

US Army Medical Research & Development Command (USAMRDC), Fort Detrick, MD 21702, USA.

Introduction: The emergence of more complex Prolonged Field Care in austere settings and the need to assist inexperienced providers' ability to treat patients create an urgent need for effective tools to support care. We report on a project to develop a phone-/tablet-based decision support system for prehospital tactical combat casualty care that collects physiologic and other clinical data and uses machine learning to detect and differentiate shock manifestation.

Materials And Methods: Software interface development methods included literature review, rapid prototyping, and subject matter expert design requirements reviews. Machine learning algorithm methods included development of a model trained on publicly available Medical Information Mart for Intensive Care data, then on de-identified data from Mayo Clinic Intensive Care Unit.

Results: The project team interviewed 17 Army, Air Force, and Navy medical subject matter experts during design requirements review sessions. They had an average of 17 years of service in military medicine and an average of 4 deployments apiece and all had performed tactical combat casualty care on live patients during deployment. Comments provided requirements for shock identification and management in prehospital settings, including support for indication of shock probability and shock differentiation. The machine learning algorithm based on logistic regression performed best among other algorithms we tested and was able to predict shock onset 90 minutes before it occurred with better than 75% accuracy in the test dataset.

Conclusions: We expect the Trauma Triage, Treatment, and Training Decision Support system will augment a medic's ability to make informed decisions based on salient patient data and to diagnose multiple types of shock through remotely trained, field deployed ML models.
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http://dx.doi.org/10.1093/milmed/usaa275DOI Listing
January 2021

Crossover between the adiabatic and nonadiabatic electron transfer limits in the Landau-Zener model.

Nat Commun 2021 01 19;12(1):456. Epub 2021 Jan 19.

Department of Chemistry, Jinan University, 601 Huang-Pu Avenue West, Guangzhou, 510632, China.

The semiclassical models of nonadiabatic transition were proposed first by Landau and Zener in 1932, and have been widely used in the study of electron transfer (ET); however, experimental demonstration of the Landau-Zener formula remains challenging to observe. Herein, employing the Hush-Marcus theory, thermal ET in mixed-valence complexes {[Mo]-(ph)-[Mo]} (n = 1-3) has been investigated, spanning the nonadiabatic throughout the adiabatic limit, by analysis of the intervalence transition absorbances. Evidently, the Landau-Zener formula is valid in the adiabatic regime in a broader range of conditions than the theoretical limitation known as the narrow avoided-crossing. The intermediate system is identified with an overall transition probability (κ) of ∼0.5, which is contributed by the single and the first multiple passage. This study shows that in the intermediate regime, the ET kinetic results derived from the adiabatic and nonadiabatic formalisms are nearly identical, in accordance with the Landau-Zener model. The obtained insights help to understand and control the ET processes in biological and chemical systems.
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http://dx.doi.org/10.1038/s41467-020-20557-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7815917PMC
January 2021

Asymmetric Regional Work Contributes to Right Ventricular Fibrosis, Inefficiency, and Dysfunction in Pulmonary Hypertension versus Regurgitation.

J Am Soc Echocardiogr 2021 May 28;34(5):537-550.e3. Epub 2020 Dec 28.

The Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada; Translational Medicine, The Hospital for Sick Children Research Institute, Toronto, Ontario, Canada. Electronic address:

Background: Right ventricular (RV) pressure loading from pulmonary hypertension (PH) and volume loading from pulmonary regurgitation (PR) lead to RV dysfunction, a critical determinant of clinical outcomes, but their impact on regional RV mechanics and fibrosis is poorly characterized. The aim of this study was to test the hypothesis that regional myocardial mechanics and efficiency in RV pressure and volume loading are associated with RV fibrosis and dysfunction.

Methods: Eight PH, six PR, and five sham-control rats were studied. The PH rat model was induced using Sugen5416, a vascular endothelial growth factor receptor 2 inhibitor, combined with chronic hypoxia. PR rats were established by surgical laceration of the pulmonary valve leaflets. Six (n = 4) or 9 (n = 4) weeks after Sugen5416 and hypoxia and 12 weeks after PR surgery, myocardial strain and RV pressure were measured and RV pressure-strain loops generated. We further studied RV regional mechanics in 11 patients with PH. Regional myocardial work was calculated as the pressure-strain loop area (mm Hg ∙ %). Regional myocardial work efficiency was quantified through wasted work (ratio of systolic lengthening to shortening work). The relation of regional myocardial work to RV fibrosis and dysfunction was analyzed.

Results: In rats, PH and PR induced similar RV dilatation, but fractional area change (%) was lower in PH than in PR. RV lateral wall work was asymmetrically higher in PH compared with sham, while septal work was similar to sham. In PR, lateral and septal work were symmetrically higher versus sham. Myocardial wasted work ratio was asymmetrically increased in the PH septum versus sham. Fibrosis in the RV lateral wall, but not septum, was higher in PH than PR. RV fibrosis burden was linearly related to regional work and to measures of RV systolic and diastolic function but not to wasted myocardial work ratio. Patients with PH demonstrated similar asymmetric and inefficient regional myocardial mechanics.

Conclusions: Asymmetric RV work and increased wasted septal work in experimental PH are associated with RV fibrosis and dysfunction. Future investigation should examine whether assessment of asymmetric regional RV work and efficiency can predict clinical RV failure and influence patient management.
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http://dx.doi.org/10.1016/j.echo.2020.12.011DOI Listing
May 2021

Effect of Human Chorionic Gonadotropin Injection Before Frozen Embryo Transfer on Pregnancy Outcomes in Endometriosis-Associated Infertility.

Front Med (Lausanne) 2020 14;7:592921. Epub 2020 Dec 14.

Reproductive Hospital Affiliated to Shandong University, Jinan, China.

The aim of this study was to investigate the effect of human chorionic gonadotropin (hCG) in hormone replacement (HT) regime for frozen thawed embryo transfer in women with endometriosis (EM). We performed a retrospective, database-search, cohort study and included data on EM patients who underwent frozen embryo transfer (FET) between January 1, 2009 and August 31, 2018. According to the protocols for FET cycle, the patients were divided into two groups: control group ( = 296) and hCG group ( = 355). Clinical pregnancy rate, live birth rate, early abortion rate, late abortion rate, and ectopic pregnancy rate were compared between the two groups. There was a significant increase in clinical pregnancy rate in the hCG group (57.7 vs. 49%, = 0.027) compared with the control group. The live birth rate in the hCG group (45.6 vs. 38.5%, = 0.080) was also elevated, but this difference was not statistically significant. hCG administration in HT regime for FET increases the pregnancy rate in women with EM.
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http://dx.doi.org/10.3389/fmed.2020.592921DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7768008PMC
December 2020

Deoiled sunflower seeds ameliorate depression by promoting the production of monoamine neurotransmitters and inhibiting oxidative stress.

Food Funct 2021 Jan 23;12(2):573-586. Epub 2020 Dec 23.

Institute of Nutrition and Health, School of Public Health, Qingdao University, Qingdao 266071, Shandong, China.

We aimed to evaluate the antidepressant activity of deoiled sunflower seeds (SFS), which are rich in tryptophan, in our mouse model and explored a possible mechanism of action. Male C57BL/6J mice were subjected to chronic unpredictable mild stress (CUMS) and were administered a diet containing SFS as the main protein source. SFS alleviated CUMS-induced depression-like behaviors, compared to the effects of a whey protein-based diet. This effect was related to increases in the levels of serotonin, dopamine, norepinephrine, acetylcholine, and brain-derived neurotrophic factor in SFS-fed mice. These changes accompanied the amelioration of inflammatory abnormalities and oxidative stress. SFS increased the aromatic amino acid levels, and the ratio of tryptophan to neutral amino acids. Furthermore, the antidepressant-like effects of SFS were involved in lipid, nucleotide, and amino acid metabolism. In summary, SFS was found to attenuate depression-like symptoms in mice. These antidepressant effects may be related to the increase in the levels of aromatic amino acids and neurotransmitters, amelioration of oxidative stress and inflammation, and the regulation of the levels of abnormal metabolites to the normal levels.
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http://dx.doi.org/10.1039/d0fo01978jDOI Listing
January 2021

Unexpected Complication of Central Venous Catheter Exchange: Catheter Fragment Migration.

Blood Purif 2021 18;50(4-5):582-587. Epub 2020 Dec 18.

Department of Nephrology, Southwest Hospital, The First Hospital Affiliated to Third Military Medical University (Army Medical University), Chongqing, China,

Tunneled central venous catheter (TCVC) placement is often an easy and uncomplicated procedure. As such, some clinicians pay little attention to the procedure, and different complications occurred. Catheter fragment loss in major vessels is a rare but serious complication of in situ catheter exchange with few reported cases in the literature. Once catheter fragments slip into a deep vein, endovascular retrieval should be attempted, due to its high success rate and minimal associated morbidity. A 37-year-old male patient underwent replacement of his temporary catheter with TCVC through a trans-right-internal-jugular-vein approach for maintenance of dialysis. As a major unintended outcome of the operation, a catheter fragment slipped into the right internal jugular vein, then migrated and lodged in the inferior vena cava. We retrieved it with a gooseneck snare without complications. We report the case hoping to emphasize on and raise awareness of the fact that catheter fragment loss is a completely evitable complication, provided the operator follows the correct safety measures and protocols. However, if catheter fragment loss occurred, the fragment should be retrieved as soon as possible. A gooseneck snare is an ideal option for retrieving catheter fragments that have migrated into deep veins.
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http://dx.doi.org/10.1159/000512353DOI Listing
December 2020

Health-Related Quality of Life and Related Factors among Primary Caregivers of Children with Disabilities in Shanghai, China: A Cross-Sectional Study.

Int J Environ Res Public Health 2020 12 12;17(24). Epub 2020 Dec 12.

School of Public Health, Fudan University, Shanghai 200032, China.

Health-related quality of life (HRQOL) of caregivers of children with disabilities (CWD) is important for both children's rehabilitation and caregivers' life, but the corresponding attention is far from enough in mainland China. Thus, we investigated the HRQOL of 170 caregivers and related factors in Shanghai. The 12-item Short Form Health Survey (SF-12) was used to measure HRQOL. The potential factors were collected, including child characteristics, caregiver characteristics, and environmental factors. Univariate analysis and multiple linear regression were performed to identify the key factors that could be intervened. Compared with the general population, caregivers of CWD had a slightly higher score on the physical component summary (PCS, 52.57 ± 8.41), but the score of mental component summary (MCS, 31.58 ± 7.72) was extremely low. Caregiver's illness condition, family size, and household income were significant factors of physical HRQOL. Caregivers with illness and caregivers living in an extended family were associated with higher mental HRQOL. Whereas these two factors had opposite effects on physical HRQOL. This finding indicated poor mental HRQOL among caregivers of CWD in Shanghai and thus requiring urgent attention and intervention. Improving physical fitness, maintaining family integration, and providing financial support should be considered when developing intervention for this population.
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http://dx.doi.org/10.3390/ijerph17249299DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7764603PMC
December 2020

Creation and grading of experimental corneal scars in mice models.

Ocul Surf 2021 01 28;19:53-62. Epub 2020 Nov 28.

From the Cornea, External Disease Service, Department of Ophthalmology, University of South Florida, Tampa, FL, USA; Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL, USA. Electronic address:

Purpose: To develop a stromal wound healing model and a reliable scar classification score system that correlates photographic evaluation with changes in the structure and organization of the extracellular matrix.

Materials And Methods: We tested three stromal injury techniques in adult C57BL/6 mice. Technique 1, a lineal partial thickness keratotomy in the horizontal axis. Technique 2, corneal epithelial and stromal debridement using a diamond burr in the horizontal axis, and technique 3, a combination of techniques 1 and 2. To assess intra-observer and inter-observer agreement between two examiners evaluating formed stromal scars, stereo microscopic photographs of anterior segment were scored by two masked examiners at around 1-month. Depending on the severity of opacification and the area of involvement, scars were classified on a scale from 0 to 3 based on a modified Fantes haze scale. Extracellular matrix composition as well as matrix organization, macrophage infiltration and neovascularization were evaluated with immunofluorescence and second harmonic generation (SHG) microscopy.

Results: Technique 1 created mild scars, with a score of 0.5 ± 0.43, while techniques 2 (score 2.1 ± 0.45) and 3 (score 2 ± 0.66), created dense scars with a higher score. A significant difference in scar severity score was noted between the 3 techniques (one way ANOVA, p < 0.0001). Masked graders demonstrated excellent agreement (intraclass correlation = 0.927 [95% confidence interval: 0.87-0.96]). The severity of scars noted at stereo microscopy correlated with the severity of changes in extracellular matrix in the stroma as demonstrated by the expression of collagens I, IV and fibronectin and evaluation of matrix hierarchical organization. In contrast to mild scarring, moderate and severe scars had increased expression of CD31 and CD68, markers of vascular endothelial cells and macrophages, respectively.

Conclusion: Mouse models of stromal scarring using simple surgical techniques are described. Corneal scars can be consistently classified by two observers. Grading of scar severity positively correlates with changes in extracellular matrix composition, disorganization and cell infiltration.
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http://dx.doi.org/10.1016/j.jtos.2020.11.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8259783PMC
January 2021

Status and Factors Associated with Healthcare Choices among Older Adults and Children in an Urbanized County: A Cross-Sectional Study in Kunshan, China.

Int J Environ Res Public Health 2020 11 23;17(22). Epub 2020 Nov 23.

Department of Health Policy and Management, School of Public Health, Fudan University, Shanghai 200032, China.

As important unit for regional health planning, urbanized counties are facing challenges because of internal migrants and aging. This study took urbanized counties in China as cases and two key populations as objects to understand different populations' intentions of choosing corresponding health service resources and to provide support for resource allocation. A cross-sectional study was conducted in Kunshan, a highly urbanized county in China, in 2016, among older adults aged 60 or over and children aged 0-6. Multinomial logistics models were used to identify the factors associated with healthcare choices. In this study, we found that income, distance of the tertiary provider, and migrant status were not associated with choices of tertiary healthcare outside county for children, while parents' education level was. The responsiveness of the tertiary provider inside the county was lower than primary and secondary providers inside the county, while respondents were dissatisfied with the medical technology and medical facility for the tertiary inside the county compared to those of the tertiary provider outside the county. Significant differences existed in terms of the perception of different categories of institutions. To conclude, local governments should particularly seek to strengthen pediatric primary health services and improve the responsiveness of healthcare facilities to treat geriatric and pediatric diseases, which also bring significance to the developing countries in the process of urbanization.
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http://dx.doi.org/10.3390/ijerph17228697DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7700310PMC
November 2020

Severity of illness and distress in caregivers of patients with schizophrenia: Do internalized stigma and caregiving burden mediate the relationship?

J Adv Nurs 2021 Mar 24;77(3):1258-1270. Epub 2020 Nov 24.

Xiangya School of Nursing, Central South University, Changsha, China.

Aims: To test a multiple mediation model of internalized stigma and caregiving burden in the relationship between severity of illness and distress among family caregivers of persons living with schizophrenia.

Design: This is a cross-sectional study.

Methods: Data were collected from a consecutive sample of 344 Chinese family caregivers of persons living with schizophrenia between April-August 2018. Instruments used in this research included the Clinical Global Impression-Severity of Illness, the Internalized Stigma of Mental Illness Scale, the Caregiver Burden Inventory, and the Distress Thermometer. Data analysis was conducted using descriptive statistics, the Spearman correlation, and regression analysis to estimate direct and indirect effects using bootstrap analysis.

Results: This research found that internalized stigma and caregiving burden can separately and sequentially mediate the relationship between severity of illness and distress. Moreover the mediation of internalized stigma plays the largest role among the multiple mediations.

Conclusion: The severity of illness, internalized stigma, and caregiving burden are significant factors of distress among family caregivers of persons living with schizophrenia. The future intervention studies which be designed aiming at the three factors may be beneficial for family caregivers of persons living with schizophrenia.

Impact: This research examined the psychosocial development of distress and indicated that interventions improving patients' symptoms and decreasing internalized stigma and caregiving burden can help to prevent or reduce distress among family caregivers.
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http://dx.doi.org/10.1111/jan.14648DOI Listing
March 2021

A Network Pharmacology to Explore the Mechanism of Membranaceus in the Treatment of Diabetic Retinopathy.

Evid Based Complement Alternat Med 2020 2;2020:8878569. Epub 2020 Nov 2.

Surgical Department of Fundus Disease and Trauma, Eye Hospital, China Academy of Chinese Medical Sciences, Beijing 100040, China.

Background: Diabetic retinopathy (DR) includes a series of typical lesions affected by retinal microvascular damage caused by diabetes mellitus (DM), which not only seriously damages the vision, affecting the life's quality of patients, but also brings a considerable burden to the family and society. Membranaceus (AM) is a commonly used medicine in clinical therapy of eye disorders in traditional Chinese medicine (TCM). In recent years, it is also used for treating DR, but the specific mechanism is unclear. Therefore, this study explores the potential mechanism of AM in DR treatment by using network pharmacology.

Methods: Based on the oral bioavailability (OB) and drug likeness (DL) of two ADME (absorption, distribution, metabolism, excretion) parameters, Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), Swiss Target Prediction platform, GeneCards, and OMIM database were used to predict and screen the active compounds of AM, the core targets of AM in DR treatment. The Metascape data platform was used to perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis on the core targets.

Results: 24 active compounds were obtained, such as quercetin, kaempferol, and astragaloside IV. There were 169 effective targets of AM in DR treatment, and the targets were further screened and finally, 38 core targets were obtained, such as VEGFA, AKT1, and IL-6. EGFR tyrosine kinase inhibitor resistance, AGE-RAGE signaling pathway in diabetic complications, PI3K-Akt signaling pathway, and other metabolic pathways participated in oxidative stress, cell apoptosis, angiogenesis signal transduction, inflammation, and other biological processes.

Conclusion: AM treats DR through multiple compounds, multiple targets, and multiple pathways. AM may play a role in the treatment of DR by targeting VEGFA, AKT1, and IL-6 and participating in oxidative stress, angiogenesis, and inflammation.
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http://dx.doi.org/10.1155/2020/8878569DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7652614PMC
November 2020

PFAS Exposure Pathways for Humans and Wildlife: A Synthesis of Current Knowledge and Key Gaps in Understanding.

Environ Toxicol Chem 2021 Mar 29;40(3):631-657. Epub 2021 Jan 29.

Harvard University, Cambridge, Massachusetts, USA.

We synthesize current understanding of the magnitudes and methods for assessing human and wildlife exposures to poly- and perfluoroalkyl substances (PFAS). Most human exposure assessments have focused on 2 to 5 legacy PFAS, and wildlife assessments are typically limited to targeted PFAS (up to ~30 substances). However, shifts in chemical production are occurring rapidly, and targeted methods for detecting PFAS have not kept pace with these changes. Total fluorine measurements complemented by suspect screening using high-resolution mass spectrometry are thus emerging as essential tools for PFAS exposure assessment. Such methods enable researchers to better understand contributions from precursor compounds that degrade into terminal perfluoroalkyl acids. Available data suggest that diet is the major human exposure pathway for some PFAS, but there is large variability across populations and PFAS compounds. Additional data on total fluorine in exposure media and the fraction of unidentified organofluorine are needed. Drinking water has been established as the major exposure source in contaminated communities. As water supplies are remediated, for the general population, exposures from dust, personal care products, indoor environments, and other sources may be more important. A major challenge for exposure assessments is the lack of statistically representative population surveys. For wildlife, bioaccumulation processes differ substantially between PFAS and neutral lipophilic organic compounds, prompting a reevaluation of traditional bioaccumulation metrics. There is evidence that both phospholipids and proteins are important for the tissue partitioning and accumulation of PFAS. New mechanistic models for PFAS bioaccumulation are being developed that will assist in wildlife risk evaluations. Environ Toxicol Chem 2021;40:631-657. © 2020 SETAC.
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http://dx.doi.org/10.1002/etc.4935DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7906948PMC
March 2021
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