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1.
Anat Sci Educ ; 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32162490

RESUMO

In mainland China, histology and embryology (HE) are taught in one course as an essential component of medical curricula. The effectiveness of HE courses directly affects the quality of medical students. To determine the present situation and changes in HE teaching in Chinese medical schools, a nationwide survey was conducted among the HE departmental leaders. In total, 66 responses were included in the study, representing prominent Chinese mainland medical schools. The results revealed that most HE teachers have medical educational backgrounds; an increasing number of teaching staff with PhDs have joined the teaching staffs. A range of 71 to 90 HE curriculum contact hours is predominant. The ratio of theory to practice for HE contact hours is 1:1 at half of the surveyed medical schools. The numbers of students in each laboratory are less than 30 and from 31-60 at 23 and 36 medical schools, respectively. Virtual microscopy is employed in 40% of the surveyed medical schools. Didactic teaching is the most common strategy, although new teaching approaches are being employed gradually. During the past twenty years, both the total number of HE teachers and the number of HE teachers with medical educational backgrounds have been reduced in at least half of the surveyed schools. A total of 83.33% of the surveyed schools have reduced their HE contact hours. Almost half of the Chinese medical schools remained unchanged in both their ratio of theory to practice and the number of students in each laboratory.The data derived from this study help to understand the development of the HE discipline at Chinese medical schools.

2.
J Nat Prod ; 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32159343

RESUMO

Environmental toxicant- and oxidant-induced [e.g., cigarette smoke (CS)] respiratory oxidative stress and inflammatory response play a vital role in the onset and progression of COPD. The nuclear factor erythroid 2-related factor 2 (Nrf2) represents an important mechanism for regulating intracellular oxidative stress and inflammatory response and is a promising target for developing agents against COPD. Herein, a bioactivity-guided purification of goldenberry (whole fruits of Physalis peruviana L.) led to the isolation of a novel and potent Nrf2 activator 4ß-hydroxywithanolide E (4ß-HWE). Our study indicated that (i) 4ß-HWE activated the Nrf2-mediated defensive response through interrupting Nrf2-Keap1 protein-protein interaction (PPI) via modification of Cys151 and Cys288 cysteine residues in Keap1 and accordingly suppressing the ubiquitination of Nrf2. (ii) 4ß-HWE enhanced intracellular antioxidant capacity and inhibited oxidative stress in normal human lung epithelial Beas-2B cells and wild-type AB zebrafish. (iii) 4ß-HWE blocked LPS-stimulated inflammatory response and inhibited LPS-stimulated NF-κB activation in RAW 264.7 murine macrophages. (iv) 4ß-HWE effectively suppressed oxidative stress and inflammatory response in a CS-induced mice model of pulmonary injury. Collectively, these results display the feasibility of using 4ß-HWE to prevent or alleviate the pathological progression of COPD and suggest that 4ß-HWE is a candidate or a leading molecule against COPD.

3.
J Alzheimers Dis ; 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32116254

RESUMO

BACKGROUND: Alzheimer's disease (AD) is the most common cause of dementia. Studies indicate that neuroinflammation plays an important role in the pathophysiology of AD. High-mobility group box 1 (HMGB1) is an important chromatin protein. It can be secreted by immune cells and passively released from damaged cells to promote inflammation. HMGB1 also can recruit stem cells and promote their proliferation and tissue repairing. However, the role of HMGB1 in the progression of AD is currently unknown. OBJECTIVE: The aims were to investigate the effect of HMGB1 on the AD-related pathologies and cognitive function using 3×Tg-AD mouse model. METHODS: Female 5-6-month-old 3×Tg-AD mice were intracerebroventricularly injected with 4.5 µg of HMGB1 or with saline as a control. The levels of interesting protein were assessed by western blots or immunofluorescence. The effect of HMGB1 on the cognitive function was evaluated by one-trial novel object recognition test and Morris water maze. RESULTS: Intracerebroventricular injection of recombinant HMGB1 ameliorated cognitive impairment in 5-6-month-old 3×Tg-AD mice. The levels of synapsin 1, synaptophysin, MAP2, NeuN, and phosphorylated CREB were increased in HMGB1-treated 3×Tg-AD mouse brains. HMGB1 decreased intracellular amyloid-ß level but did not affect tau phosphorylation. HMGB1 treatment also promoted neurogenesis in the dentate gyrus and increased the level of GFAP in the 3×Tg-AD mouse brains. CONCLUSION: These results reveal a novel function of HMGB1 in enhancing neuroplasticity and improving cognitive function in 3×Tg-AD mice.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32160379

RESUMO

Li metal is recognized as one of the most promising anode materials owing to its ultrahigh theoretical specific capacity and low electrochemical potential. Nonetheless, dendritic Li growth has dramatically hindered the practical applications of Li metal anode. Realizing spherical Li deposition is an effective approach to avoid Li dendrite growth, but the mechanism of spherical deposition is unknown. In this contribution, a diffusion-reaction competition mechanism is proposed to reveal the rationale of different Li deposition morphologies. By controlling the rate-determining step (diffusion or reaction) of Li deposition, various Li deposition scenario are realized, where the diffusion-controlled process tends to form dendritic Li deposition while the reaction-controlled process leads to spherical Li deposition. This study sheds fresh light on the dendrite-free Li metal anode and guides to achieve safe batteries to benefit future wireless and fuel-free world.

5.
J Hazard Mater ; 393: 122399, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32151931

RESUMO

Advanced oxidation processes (AOPs) based on the bimetallic system has been demonstrated as a promising way to enhance the degradation of pollutants in the water. In this study, the degradation of Rhodamine B (RhB) in a zero-valent iron (ZVI)/ peroxymonosulfate system with Cu2+ was thoroughly investigated. RhB could be efficiently removed (99.3 %) in the optimal ZVI/PMS/Cu2+ system, while only 58.2 % of RhB could be degraded in the ZVI/PMS system. The influence of reaction parameters on the degradation of RhB was further investigated. Quenching experiments and electron paramagnetic resonance (EPR) tests revealed that various reactive oxygen species could be generated in the ternary system, of which, 1O2 and O2- were identified for the first time. The effect of various anions, NOM and different water matrix were also considered at different concentrations. A variety of byproducts and degradation pathways were identified using HPLC/MS/MS. Finally, the Quantitative Structure Activity Relationship (QSAR) method of Toxicity Estimation Software Tool (TEST) was applied to estimate the toxicity of the byproducts and the results indicated that the overall toxicity of the target was relatively reduced. This study demonstrated the potential for the removal of environmental reluctant pollutants in water via the combined radical and non-radical pathways.

6.
Food Chem ; 319: 126555, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32163840

RESUMO

Rapid, green and efficient extraction of active compounds followed by fast analysis is always pursued in the field of food analysis and/or industry. Herein, a green and highly efficient extraction of four active flavonoids from the seeds of Oroxylum indicum using a combination of natural deep eutectic solvents (DESs) and tissue-smashing extraction (TSE) technique was applied and a UPLC method was developed for their sensitive and selective quantification. RSM coupled with BBD procedure was used to optimize the extraction conditions based on single factors, such as liquid-solid ratios, extraction speed and extraction time. Compared with other conventional methods, the TSE greatly shortens extraction time, obviously raises the extraction production, and decreases energy consumption. By combination of the DES-based TSE and UPLC, the analysis of flavonoids was accomplished within only 6 min, providing an ultra-rapid, environmentally friendly and promising choice for extraction and analysis of active compounds in natural products.

7.
Ecotoxicol Environ Saf ; 194: 110415, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32151871

RESUMO

Zinc oxide Nanoparticles (ZnO NPs) are widely used as emerging materials in agricultural and food-related fields, which exists potential safety hazards to public health and environment while bringing an added level of convenience to our original life. It has been proved that ZnO NPs could be taken up by pregnant women and passed through human placental barrier. However, the toxic potential for embryo development remains largely unanswered. In this study, we discovered that ZnO NPs caused the cytotoxicity in vitro. Inhibition of free Zn2+ ions in solution by EDTA or inhibition of Zn2+ ions absorption by CaCl2 could partially eliminate ZnO NPs-mediated cell toxicity, though not redeem completely. This indicated that both nanoparticles and the release of Zn2+ ions were involved in ZnO NPs-mediated cytotoxicity. In addition, we also found that both nanoparticles and Zn2+ ion release triggered reactive oxygen species (ROS) production, which further induced cell toxicity, inflammation and apoptosis, which are mediated by NF-κB signaling cascades and the mitochondria dysfunction, respectively. Eventually, these events lead to the suppressed production and migration of cranial neural crest cells (CNCCs), which subsequently prompts the craniofacial defects in chicken embryos. The application of the antioxidant N-Acetyl-L-cysteine (NAC) rescued the ZnO NPs-induced cell toxicity and malformation of the CNCCs, which further verified our hypothesis. Our results revealed the relevant mechanism of ZnO NPs exposure-inhibited the development of CNCCs, which absolutely contribute to assess the risk of nanoparticles application.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 56-62, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027253

RESUMO

OBJECTIVE: To investigate the expression and significance of B and T lymphocyte weakening factor (BTLA) in patients with chronic myelomonocytic leukemia (CMML). METHODS: Real-time PCR was used to detect the expression of BTLA and its ligand HVEM mRNA in 11 patients with chronic myelomonocytic leukemia and 11 normal donors. Flow cytometry was used to detect expression of BTLA and its HVEM on the cell surface of peripheral blood T lymphocytes and γδ T cells. RESULTS: The median values of BTLA and its ligand HVEM mRNA expression in peripheral blood of patients with CMML were 0.009% and 559.4%, respectively, which were significantly lower than those of normal controls (0.053% and 1031%)(P<0.001). The expression level of BTLA and HVEM on cell surface of peripheral lymphocytes was not significantly different from that in normal controls (P=0.3031 and 0.2576), however, the proportion of peripheral blood T lymphocytes in patients with CMML (median: 37.73%) was significantly lower than that in controls (median 69.23%)(P=0.0005). The expression of BTLA on the surface of γδ T cells in peripheral blood of patients with CMML (median: 23.26%) was significantly lower than that of the controls (median: 52.64%) (P<0.05), and there was no significant abnormality in HVEM expression (P=0.2791). CONCLUSION: The expression of BTLA and its ligand HVEM, the proportion of T lymphocytes and the expression of BTLA on the surface of γδ T cells in patients with CMML are reduced. The effects of these abnormalities on T cell function and prognosis and efficacy of patients need to be further observed.


Assuntos
Leucemia Mielomonocítica Crônica , Receptores Imunológicos/genética , Membro 14 de Receptores do Fator de Necrose Tumoral/genética , Humanos , Leucemia Mielomonocítica Crônica/genética , Ligantes , Linfócitos T
9.
J Hazard Mater ; 391: 122055, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32045799

RESUMO

Nitrogen and sulfur-codoped porous carbons (SNCs) with porous structures and high surface areas were successfully synthesized employing coffee grounds, sodium bicarbonate and L-cysteine monohydrochloride as precursors. The SNCs were highly efficient for adsorption and exhibited outstanding catalytic performance for the oxidative degradation of tetracycline hydrochloride (TeC) solutions, especially at a calcined temperature of 700 °C (SNCs-700). The radical quenching, advanced in situ electron paramagnetic resonance (EPR) technology, PS decomposition rates and Linear Sweep Voltammetry (LSV) indicated that the excellent oxidative effectiveness of the PS/SNCs-700 system originated from the nonradical pathways (singlet oxygen (1O2) and electron transfer). It's supposed that N and S doping can effectively create point defects, which could generate 1O2, while carbonyl groups were determined to be the main active sites contributing to the electron transfer. TeC degradation intermediates were also identified, three degradation pathways, revealing that the pre-adsorption significantly accelerated the nonradical oxidation pathways. This approach provides an innovative method for the large-scale production and application of high-quality catalysts in water treatment.

10.
J Hazard Mater ; 391: 122228, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32062541

RESUMO

Though natural reducing agents have been demonstrated as desirable catalysts for environmental remediation, the mechanism of catalytic activation of persulfate (PS) by bisulfite (S(IV)) remains unclear. In this study, an emerging contaminant bisphenol AF (BPAF) was employed as the target compound to examine the activation and degradation mechanism in PS/S(IV) system. Sulfate radical (SO4•-) was evidenced as the dominant radical accounting for BPAF degradation via quantitative analysis, while hydroxyl radical (•OH) and singlet oxygen (1O2) were minor contributors. Superoxide radical (O2•-) was identified as an intermediate radical in promoting BPAF removal through quenching experiments and electron paramagnetic resonance analysis. Tests in oxygen-rich and oxygen-deficient systems were conducted and the results were contrasted to elucidate the important role of oxygen in BPAF degradation and SO4•--formation. In addition, the effect of Dissolved Oxygen (DO) was simulated using two separate kinetic models. Decomposition mechanism of BPAF was afterwards clarified via the density-functional theory calculations using Fukui index to predict the vulnerable sites and the intermediate products. This study provides a mechanistic understanding of the activation of PS/S(IV) system on the BPAF removal, especially the critical role of DO and O2•- in SO4•- generation.

11.
J Card Surg ; 35(3): 683-685, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31971268

RESUMO

A 66-year-old female patient was admitted with abdominal bleeding as an unexpected complication of robotic surgery. Assessments included the patient's medical history, physical examination, laboratory data, and abdominal ultrasound scan results. In our case, laparotomy revealed an injury to the diaphragm and liver of the patient caused by the previous robotic surgery. In conclusion, although abdominal bleeding is a rare condition, it should be taken into consideration as a complication of robotic cardiac surgery.

12.
Inorg Chem ; 59(2): 1376-1382, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31891485

RESUMO

Composition modulation is an efficient strategy for improving the performance of Pt-based electrocatalysts for direct methanol fuel cells. Unfortunately, a robust route for the composition modulation of one-dimensional multicomponent nanowire electrocatalysts remains a tremendous challenge. Herein, we report a versatile method for high-quality Pt-based nanowires and nanotubes, which exhibit composition-dependent performance for the methanol oxidation reaction, through a simple solvothermal process. Among these catalysts, quaternary PtRuAgTe nanotubes possess the lowest onset potential of 0.387 V and display the highest activity of 1145 mA mg-1 Pt, which is ∼3.0 times that of commercial Pt/C, exhibiting the best long-term durability over 30000 s owing to the synergistic effect between compositions as well as the favorable tubelike structure. Moreover, synchrotron radiation photoelectron spectroscopy is introduced to investigate the structural behavior of the catalysts before and after the catalytic process. This work contributes a simple method toward scalable production of high-performance Pt-based nanowires and nanotubes for applications in electrocatalysts and affords an inspiring route to enhance both the catalytic activity and the durability.

13.
ACS Appl Mater Interfaces ; 12(5): 5767-5774, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31922385

RESUMO

Lithium metal is among the most promising anode candidates of high-energy-density batteries. However, the formed dendrites result in low Coulombic efficiency and serious security issues. Designing lithiophilic sites is one of the effective strategies to control Li deposition. Herein, we propose a three-dimensional lithiophilic N-rich carbon nanofiber with the decoration of ZnO granules as a protective layer for a dendrite-free lithium metal anode. Theoretical evaluation indicates the synergistic effects of lithiophilic ZnO and N-containing functional groups enhance lithium adsorption and trigger uniform deposition. With the lithiophilic interlayer, the lithium deposition overpotential is only ∼20, 50, and 74 mV at 1, 3, and 6 mA cm-2, respectively, which are much lower than those without the functional interlayer (∼55, 130, and 238 mV). The average Coulombic efficiency of lithium stripping and plating is up to ∼97.4% (94.0% for that without the interlayer) at 0.5 mA cm-2. Meanwhile, the Li|LiFePO4 full cell with the superlithiophilic interlayer demonstrates a high capacity retention rate of 99.6% (91.0% for that without the interlayer) over 200 cycles at 1 C. The introduction of the lithiophilic interphase could provide a convenient strategy and guidance to design the configuration for the practical application of Li metal batteries.

14.
ACS Appl Mater Interfaces ; 12(5): 6082-6089, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31939651

RESUMO

Advances in smart and wearable devices are driving innovations in multifunctional flexible materials at a tremendous pace. Here, drawing support from the unique flexible fluorophlogopite mica platform, we present a promising all-inorganic bendable Mn-modified 0.65(0.94Na0.5Bi0.5TiO3-0.06BaTiO3)-0.35SrTiO3 (NBBST) film with dual use in electrocaloric (EC) refrigeration and energy storage via a cost-effective transfer-free process. An appreciable room-temperature EC effect with adiabatic temperature change of 12 K and isothermal entropy of 18 J K-1 kg-1 was realized in the NBBST film, which benefits from the large change in dipolar ordering near depolarization temperature. Also, the film exhibits a broad operating temperature span over 25 °C because of its relaxor feature. Most importantly, the film can maintain a high EC performance either under bending deformation at 5 mm radius or after undergoing 104 bending-unbending cycles. Meanwhile, the flexible NBBST film possesses good energy storage property with a recoverable energy density of 56 J cm-3 and an efficiency of 66%. This is the first example of a lead-free all-inorganic multifunctional film capacitor toward the flexible EC refrigeration and energy storage devices. This work shows bright prospects in the emerging flexible e-market.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31897871

RESUMO

This paper systematically studied the mass concentration levels of PM2.5 and PM10 and obtained the morphological characteristics and components of the particles through scanning electron microscopy (SEM-EDX) and discussed the sources of the particles. Meanwhile, the health risk was evaluated according to the mass concentration of particulate matter. The results showed that the average annual PM2.5 and PM10 in the eastern part of Chengdu were 101.99 µg/m3 and 168.89 µg/m3, respectively, exceeding the national second-level average annual air quality standard (GB3095-2012). Both of them were the highest in winter and the lowest in summer and had a significant positive correlation. The atmospheric particles in the study area were mainly composed of fly ash particles, soot aggregates, mineral particles (sulfate mineral particles, carbonate mineral particles, etc.), which mainly came from coal burning, dust, automobile exhaust and secondary products. The results of the health risk assessment showed that the mass concentration of PM2.5 and PM10 in the atmosphere of the eastern part of Chengdu exceeded the IT-1 target. The average annual air quality index was 185.84, and the air quality index was level 4, classified as medium pollution. PM10 and PM2.5 were both excessive pollutants, and PM10 was the primary pollutant. Relevant measures should be taken to control particulate matter sources to some extent.

17.
J Control Release ; 319: 234-245, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31899269

RESUMO

Adenosine (Ade) has been identified to stimulate bone formation. However, the use of Ade is severely limited by the accompanying side effects and its very short half-life in vivo. This study aimed to fabricate an efficient drug-delivery system to reduce the undesirable side effects and enable the clinical application of Ade for treating large bone defects. The fabricated poly(ε-caprolactone) (PCL)/Ade-polyvinyl alcohol (PVA)(0.3/0.4) nanofibrous mats with 0.3:0.4 (w/w) ratio of Ade and PVA showed a sustained and controlled release of Ade and facilitated the osteogenic differentiation of bone mesenchymal progenitor cells (BMSCs). A larger amount of newly formed bone was observed in vivo in the cranial defects of the PCL/Ade-PVA(0.3/0.4) group compared with those of the non-loaded PCL/PVA nanofibrous mats at 4 and 8 weeks after surgery. Moreover, it is the first time to confirm that Ade mediates the osteogenesis of rat BMSCs through the STAT3 signaling pathway and restrains the osteoclastogenesis of rat bone-marrow macrophages (BMMs). These results suggested that this coaxial drug-delivery system loaded with Ade provided a promising and clinically relevant platform to controlled-release Ade and address large bone defects.

18.
Pharmacol Res ; 153: 104655, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31996327

RESUMO

Ischemia/reperfusion (IR) induces additional damage during the restoration of blood flow to ischemic myocardium. Urolithin B (UB) is one of the gut metabolites of ellagitannins, a class of antioxidant polyphenols, which was found to be protective against oxidative stress in multiple organs. However, the role of UB in cardiovascular disease remains elusive. Adult Sprague Dawley rats were subjected to left anterior descending artery ligation for 30 min followed by 120 min of reperfusion, with or without UB treatment. In vitro, the H9c2 cardiomyocytes were subjected to hypoxia (94 %N2/5 %CO2/1 %O2) for 3 h, followed by reoxygenation (74 %N2/5 %CO2/21 %O2) for 3 h (HR). UB was found to decrease myocardial infarct size and attenuate the cardiac dysfunction in the rats after IR, and protect against HR injury in H9c2 cardiomyocytes. Mechanistically, UB inhibited autophagy by activating Akt/mTOR/ULK1 pathway and protected against oxidative stress and caspase 3-dependent cell apoptosis. In particular, UB induced accumulation of p62 and its interaction with Keap1, which promoted Nrf2 nuclear translocation during HR insult. Of note, the protection of UB against superoxide production and apoptotic cell death was compromised with Nrf2 gene silencing. Taken together, our findings suggested that UB protected against myocardial IR injury at least partially via the p62/Keap1/Nrf2 signaling pathway, which highlights the potential of UB as a novel therapy for ischemic heart disease.

19.
Brain Pathol ; 30(2): 283-297, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31376192

RESUMO

Alzheimer's disease (AD) is characterized by the presence of extracellular amyloid ß plaques and intraneuronal neurofibrillary tangles of hyperphosphorylated microtubule-associated protein tau in the brain. Aggregation of transactive response DNA-binding protein of 43 kDa (TDP-43) in the neuronal cytoplasm is another feature of AD. However, how TDP-43 is associated with AD pathogenesis is unknown. Here, we found that casein kinase 1ε (CK1ε) phosphorylated TDP-43 at Ser403/404 and Ser409/410. In AD brains, the level of CK1ε was dramatically increased and positively correlated with the phosphorylation of TDP-43 at Ser403/404 and Ser409/410. Overexpression of CK1ε promoted its cytoplasmic aggregation and suppressed TDP-43-promoted tau mRNA instability and tau exon 10 inclusion, leading to an increase of tau and 3R-tau expressions. Levels of CK1ε and TDP-43 phosphorylation were positively correlated with the levels of total tau and 3R-tau in human brains. Furthermore, we observed, in pilot immunohistochemical studies, that the severe tau pathology was accompanied by robust TDP-43 pathology and a high level of CK1ε. Taken together, our findings suggest that the elevation of CK1ε in AD brain may phosphorylate TDP-43, promote its cytoplasmic aggregation and suppress its function in tau mRNA processing, leading to acceleration/exacerbation of tau pathology. Thus, the elevation of CK1ε may link TDP-43 to tau pathogenesis in AD brain.

20.
J Hazard Mater ; 385: 121528, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31735468

RESUMO

Concentrations of Pb and Cd in topsoil from 24 locations along the Baguan River near a smelting dump in west Panzhihua were measured using ICP-MS to examine the spatial distributions of these toxic heavy metals. Twenty-one profile samples, 7 from each of 3 locations down to 80 cm, were also analyzed to establish background levels and Pb - Cd correlations. Lead isotopic ratios in all 45 samples and potential sources of soil contamination were determined using MC-ICP-MS. Contamination levels of Pb and Cd in soils from both sides of the river ranged from low to moderate, and the concentrations of Pb and Cd exhibited highly correlated behavior. Results of an isotope-tracer technique determined the number of end-member contaminants and background compositions contributing to the compositions of topsoils. Results of a binary mixing model indicated that contaminants in upslope soils from relatively higher elevations were coal and derivative products, and that these soils are isotopically distinct from downslope soils. Contaminants in downslope soils were slag and derivative products from V processing. Results demonstrate the use of Pb isotopic tracers in low-to-moderate contaminant levels to predict potential sources and Pb is a viable surrogate to trace potential Cd contamination in Panzhihua region.

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