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1.
J Cell Mol Med ; 28(7): e18158, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38494853

ABSTRACT

The increasing attention towards diabetic cardiomyopathy as a distinctive complication of diabetes mellitus has highlighted the need for standardized diagnostic criteria and targeted treatment approaches in clinical practice. Ongoing research is gradually unravelling the pathogenesis of diabetic cardiomyopathy, with a particular emphasis on investigating various post-translational modifications. These modifications dynamically regulate protein function in response to changes in the internal and external environment, and their disturbance of homeostasis holds significant relevance for the development of chronic ailments. This review provides a comprehensive overview of the common post-translational modifications involved in the initiation and progression of diabetic cardiomyopathy, including O-GlcNAcylation, phosphorylation, methylation, acetylation and ubiquitination. Additionally, the review discusses drug development strategies for targeting key post-translational modification targets, such as agonists, inhibitors and PROTAC (proteolysis targeting chimaera) technology that targets E3 ubiquitin ligases.


Subject(s)
Diabetes Mellitus , Diabetic Cardiomyopathies , Humans , Diabetic Cardiomyopathies/genetics , Protein Processing, Post-Translational , Ubiquitination , Phosphorylation , Ubiquitin-Protein Ligases/metabolism
2.
Environ Geochem Health ; 46(3): 104, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38438597

ABSTRACT

Park dust is a carrier of heavy metal pollutants and could potentially harm the health of urban residents. The concentrations of 10 heavy metal(loid)s (HMs) in park dust from the Mianyang urban area were analysed via X-ray fluorescence spectrometry. Based on ArcGIS spatial analysis, Spearman correlation analysis, spatial autocorrelation analysis, and the positive matrix factorization (PMF) model, the spatial distribution and sources of HMs in park dust were studied. The average contents of Zn, Co, Cu, Cr, Pb, and Ba in park dust were 185.0, 33.7, 38.7, 178.7, 51.0, and 662.1 mg/kg, respectively, which are higher than the reference values. The 10 HMs exhibited obvious spatial distribution and local spatial agglomeration patterns. High concentrations of As and Pb were primarily concentrated in the eastern part of the Mianyang urban area. High concentrations of Zn, Cr, and Cu were largely distributed in parks near the Changjiang River and Fujiang River. A high concentration of Co was concentrated in the northern region. The high-value areas of Mn, Ba, V, and Ni occurred far from the city centre and were located in the southwestern region. We found that Pb and As primarily originated from mixed traffic and natural sources; Zn, Cr, and Cu mainly originated from industrial activities; Co largely originated from building sources; and Ba, Ni, Mn, and V were mostly derived from natural sources. Mixed, industrial, building, and natural sources accounted for 24.5%, 24.8%, 24.7%, and 26.0%, respectively, of the HM sources. Co, Cu, Cr, and Zn in the Mianyang urban area were obviously influenced by human activities and should receive close attention.


Subject(s)
Environmental Pollutants , Metals, Heavy , Humans , Lead , China , Dust
3.
J Environ Manage ; 347: 119056, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37757688

ABSTRACT

Contamination, hazard level and source of 10 widely concerned potentially toxic metal(loid)s (PTMs) Co, As, Pb, Cr, Cu, Zn, Ni, Mn, Ba, and V in fine dust with particle size below 63 µm (FD63) were investigated to assess the environmental quality of college campuses and influencing factors. PTMs sources were qualitatively analyzed using statistical methods and quantitatively apportioned using positive matrix factorization. Probabilistic contamination degrees of PTMs were evaluated using enrichment factor and Nemerow integrated enrichment factor. Eco-health risk levels of content-oriented and source-oriented for PTMs were evaluated using Monte Carlo simulation. Mean levels of Zn (643.8 mg kg-1), Pb (146.0 mg kg-1), Cr (145.9 mg kg-1), Cu (95.5 mg kg-1), and Ba (804.2 mg kg-1) in FD63 were significantly larger than soil background values. The possible sources of the concerned PTMs in FD63 were traffic non-exhaust emissions, natural source, mixed source (auto repair waste, paints and pigments) and traffic exhaust emissions, which accounted for 45.7%, 25.4%, 14.5% and 14.4% of total PTMs contents, respectively. Comprehensive contamination levels of PTMs were very high, mainly caused by Zn pollution and non-exhaust emissions. Combined ecological risk levels of PTMs were low and moderate, chiefly caused by Pb and traffic exhaust emissions. The non-cancer risks of the PTMs in FD63 to college students fell within safety level, while the carcinogenic PTMs in FD63 had a certain cancer risks to college students. The results of source-specific health risk assessment indicated that Cr and As were the priority PTMs, and the mixed source was the priority pollution source of PTMs in FD63 from college campuses, which should be paid attention to by the local government.


Subject(s)
Metals, Heavy , Soil Pollutants , Humans , Metals, Heavy/analysis , Environmental Monitoring/methods , Dust/analysis , Lead , Monte Carlo Method , Soil Pollutants/analysis , Risk Assessment , China , Cities
4.
Environ Geochem Health ; 44(10): 3541-3554, 2022 Oct.
Article in English | MEDLINE | ID: mdl-34625867

ABSTRACT

The spatial distribution, pollution level, and exposure risk of Pb in the finer dust (particle size < 63 µm) of residential areas in Xi'an, northwest China were investigated in this study. Geographical information systems and geodetector methods were used to analyze the spatial variability of Pb content in the finer dust of Xi'an and its forming mechanism. The enrichment factor was used to assess the extent of Pb pollution, and the hazard index was used to evaluate the health risks to children and adults exposed to Pb. The results showed that the average content of Pb in the finer dust of residential areas in Xi'an was 99.9 mg kg-1. In the Xi'an urban area, a higher Pb content was mainly found in the finer dust near the Second Ring Road of Xi'an City, and the Pb content in the old town of Xi'an City was relatively lower than that near the Second Ring Road. The results of geodetector analysis indicate that the spatial variability of Pb in the finer dust of the Xi'an urban area was primarily controlled by the interaction among vehicle emissions, daily behavior of residents, and industrial emissions. Pb in the finer dust from residential areas in all districts showed moderate enrichment. The non-cancer risks of Pb in the finer dust were within the safe range for both children and adults. However, the prolonged exposure risk of Pb in the finer dust of residential areas should be considered for children.


Subject(s)
Dust , Lead , Adult , Child , China , Cities , Dust/analysis , Environmental Monitoring/methods , Humans , Lead/analysis , Risk Assessment , Vehicle Emissions/analysis
5.
Environ Res ; 202: 111703, 2021 11.
Article in English | MEDLINE | ID: mdl-34284017

ABSTRACT

College students study and live at university for several years; however, the pollution levels, ecological health risks, and sources of heavy metals and metalloids (HMMs) in the dust found at university campuses are still unknown. In this study, dust samples from university campuses in Xi'an were collected and the Zn, Mn, As, Pb, V, Cr, Co, Cu, Ba, and Ni contents were measured using X-ray fluorescence spectrometry. The pollution levels and ecological health risks of these HMMs were evaluated using the geo-accumulation, pollution load, and potential ecological risk indices and a health risk assessment model while their sources were apportioned using positive matrix factorization. The mean HMM concentrations in the dust were higher than the corresponding background values in the topsoil of Shaanxi Province. The Mn, V, Co, As, and Ni concentrations in the dust samples analyzed were within the levels categorized as no pollution by the geo-accumulation index standard, whereas other HMMs caused pollution to different degrees. Assessment of the pollution load index indicated that the dust samples analyzed were moderate contamination with HMMs. Pb and Cu in the dust presented considerable and moderate ecological risks, respectively; the other HMMs presented low ecological risks. The combined ecological risk of the HMMs measured in the dust samples was considerable. The non-carcinogenic and carcinogenic risks to male and female college students were within the safe levels. This study found three main sources of the HMMs measured in the dust: traffic, natural, and mixed sources (the latter including automobile repair industry waste and paints and pigments), which accounted for 47.5%, 29.3%, and 23.2% of the total HMM concentration, respectively.


Subject(s)
Metalloids , Metals, Heavy , Soil Pollutants , China , Cities , Dust/analysis , Environmental Monitoring , Female , Humans , Male , Metalloids/analysis , Metals, Heavy/analysis , Risk Assessment , Soil Pollutants/analysis , Universities
6.
Ecotoxicol Environ Saf ; 208: 111679, 2021 Jan 15.
Article in English | MEDLINE | ID: mdl-33396011

ABSTRACT

A comprehensive study on concentration, spatial distribution, pollution, ecological-health risk and source of potentially toxic elements (PTEs) in dust of residential area in Xi'an, China were conducted to explore the environmental quality of residential area in urban district. The results show that the concentrations of V, Ni, and Mn in the dust were less than, while the contents of Cr, Zn, Pb, Cu, and Ba in the dust were obviously larger than, the soil background values of Shaanxi. The high-value area of PTEs primarily concentrated in densely populated areas, heavily trafficked areas and the surroundings of plants. Cr, Pb and Zn posed moderate enrichment and Pb possessed moderate ecological risk in the dust. The comprehensive pollution levels of PTEs in the dust were uncontaminated to moderately contaminated and their comprehensive ecological risk were moderate. The non-carcinogenic risks of the PTEs for adults and children were in the safe level and the carcinogenic risks of Ni and Cr were under the current acceptable value. Four major sources were discriminated on basis of the multivariate statistical analysis results and the content characteristics, enrichment degrees, and the spatial distribution features of the PTEs, viz. Mn, V, and Ni primarily came from natural source; Pb, Zn, and Cu mainly originated from traffic source; and Ba and Cr were respectively from construction source and coal-fired power plant source, which respectively contributed 22.8%, 28.3%, 47.3%, and 1.6% to the total content of PTEs determined in the dust.


Subject(s)
Dust/analysis , Environmental Monitoring/methods , Environmental Pollution , Metals, Heavy , Adult , Carcinogens/analysis , Carcinogens/toxicity , Child , China , Environmental Pollution/adverse effects , Environmental Pollution/analysis , Humans , Metals, Heavy/analysis , Metals, Heavy/toxicity , Risk Assessment , Soil/chemistry , Soil Pollutants/analysis , Soil Pollutants/toxicity , Urbanization
7.
Arch Environ Contam Toxicol ; 77(4): 575-586, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31286175

ABSTRACT

Sixty-two topsoil samples were collected within the third ring road of Xi'an City in Northwest China and analyzed by X-ray fluorescence spectrometry for the concentrations of As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn. The pollution levels of trace metals were assessed by pollution index (PI) and Nemerow pollution index (NPI). Meanwhile, the sources of trace metals were apportioned by receptor models, including positive matrix factorization (PMF), UNMIX, and principal component analysis-multiple linear regression (PCA-MLR). The average concentrations of the trace metals analyzed in the urban soil exceeded the corresponding soil element background values of Shaanxi Province, especially for Co, which was 2.38 times higher than the corresponding background value. The mean of PI was 2.38 for Co, reflecting a moderate pollution level, and ranged from 1.07 to 1.72 for other trace metals, presenting slight pollution levels. The NPI of trace metals varied between 1.20 and 3.50 with an average of 2.00, indicating that trace metals presented slight pollution in 62.90% of soil samples, moderate pollution in 30.65% of soil samples, and heavy pollution in 6.45% of soil samples, respectively. Three sources of trace metals apportioned by the three receptor models were mixed nature and anthropogenic source, traffic exhaust, and industrial emissions. The contributions of them were 38.58%, 32.72%, and 28.70% from the PMF, 65.36%, 17.76%, and 16.88% through the UNMIX and 49.16%, 38.90%, and 11.94% via the PCA-MLR, respectively. Meanwhile, the study results suggested that the combined usage of multiple receptor models is a good method to apportion the source compositions and contributions of trace metals in urban soil.


Subject(s)
Metals/analysis , Soil Pollutants/analysis , China , Cities , Environmental Monitoring/methods , Environmental Pollution/analysis , Industry , Linear Models , Metals, Heavy/analysis , Principal Component Analysis , Soil/chemistry
8.
Biochim Biophys Acta Gen Subj ; 1862(7): 1576-1583, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29627450

ABSTRACT

GroEL along with ATP and its co-chaperonin GroES has been demonstrated to significantly enhance the folding of newly translated G-protein-coupled receptors (GPCRs). This work extends the previous studies to explore the guest capture and release processes in GroEL-assisted folding of GPCRs, by the reduced approach of employing CXCR4 transmembrane peptides as model substrates. Each of the CXCR4-derived peptides exhibited high affinity for GroEL with a binding stoichiometry near seven. It is found that the peptides interact with the paired α helices in the apical domain of the chaperonin which are similar with the binding sites of SBP (strongly binding peptide: SWMTTPWGFLHP). Complementary binding study with a single-ring version of GroEL indicates that each of the two chaperonin rings is competent for accommodating all the seven CXCR4 peptides bound to GroEL under saturation condition. Meanwhile, the binding kinetics of CXCR4 peptides with GroEL was also examined; ATP alone, or in combination of GroES evidently promoted the release of the peptide substrates from the chaperonin. The results obtained would be beneficial to understand the thermodynamic and kinetic nature of GroEL-GPCRs interaction which is the central molecular event in the assisted folding process.


Subject(s)
Chaperonin 60/metabolism , Receptors, CXCR4/metabolism , Adenosine Triphosphate/pharmacology , Amino Acid Sequence , Binding Sites , Binding, Competitive , Chaperonin 10/chemistry , Chaperonin 10/metabolism , Chaperonin 60/chemistry , Chaperonin 60/genetics , Humans , Kinetics , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Protein Binding , Protein Domains , Protein Folding , Protein Interaction Mapping , Protein Structure, Secondary , Receptors, CXCR4/chemistry , Thermodynamics
9.
Ecotoxicol Environ Saf ; 151: 153-160, 2018 Apr 30.
Article in English | MEDLINE | ID: mdl-29334637

ABSTRACT

As soil-extractable elements potentially pose ecological and health risks, identifying their contamination characteristics and sources is crucial. Therefore, to understand topsoil trace elements in the urban ring zone from the Second Ring Road to the Third Ring of Xi'an city in China, we determined the concentrations of Zn, Co, V, As, Cu, Mn, Ba, Ni and Pb, and analyzed the sources of the contamination. The results showed that the individual pollution indices of Pb, Co, Cu, Zn, Ba, Ni, Mn, As, and V were 1.79, 1.48, 1.41, 1.33, 1.20, 1.07, 1.04, 0.99, and 0.99, respectively. Evaluation with the aid of the pollution load index (PLI) indicated slight soil contamination by these elements in the study area. Using the positive matrix factorization (PMF) method, we identified four sources of contamination, namely (1) a natural source, (2) traffic emission source, (3) industrial emission source, and (4) mixed source. PMF is an effective tool for source apportionment of heavy metals in topsoil. The contribution rates of the natural source, traffic source, mixed source, and industrial source to the heavy metal contamination were specified as 25.04%, 24.71%, 24.99%, and 25.26%, respectively. Considering the above, any attempt to reduce the soil environmental cost of urban development, has to take into account the heavy metal contamination of the topsoil from industries, traffic, and other activities.


Subject(s)
Metals, Heavy/analysis , Soil Pollutants/analysis , China , Cities , Environmental Monitoring , Industry , Soil , Trace Elements/analysis
10.
Arch Environ Contam Toxicol ; 75(3): 351-366, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29589045

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the environment. This study collected a total of 62 urban soil samples from the typical semi-arid city of Xi'an in Northwest. They were analyzed for the composition, distribution, and sources of PAHs as well as the relationships with soil properties. The sum of 16 individual PAHs (∑16PAHs) ranged from 390.6 to 10,652.8 µg/kg with a mean of 2052.6 µg/kg. The average ∑16PAHs decreased in the order of the third ring road (2321.1 µg/kg) > the first ring road (1893.7 µg/kg) > the second ring road (1610.0 µg/kg), and in the order of industrial areas (3125.6 µg/kg) > traffic areas (2551.6 µg/kg) > educational areas (2414.4 µg/kg) > parks (1649.5 µg/kg) > mixed commercial and traffic areas (1332.8 µg/kg) > residential areas (1031.0 µg/kg). The most abundant PAHs in the urban soil were 3- to 5-ring PAHs. Elevated levels of PAHs were found in industrial and traffic areas from the east and west suburbs and the northwest corner of Xi'an as well as the northeast corner in the urban district of Xi'an. PAHs in the urban soil were mainly related to the combustion of fossil fuel (i.e., coal, gasoline, diesel, and natural gas) and biomass (i.e., grass and wood) (variance contribution 57.2%) as well as the emissions of petroleum and its products (variance contribution 29.9%). Soil texture and magnetic susceptibility were the main factors affecting the concentration of PAHs in urban soil. Meanwhile, this study suggested that the single, rapid, and nondeductive magnetic measurements can be an indicator of soil pollution by PAHs.


Subject(s)
Environmental Monitoring/methods , Polycyclic Aromatic Hydrocarbons/analysis , Soil Pollutants/analysis , Biomass , China , Cities , Coal , Environmental Pollution , Industry , Petroleum , Soil/chemistry , Wood
11.
J Org Chem ; 82(11): 5873-5880, 2017 06 02.
Article in English | MEDLINE | ID: mdl-28493702

ABSTRACT

CuI-catalyzed diverse functionalizations of C60 with amino alcohols with aerobic oxygen as the sole oxidant have been explored. For 2-/3-amino alcohols, an aminooxygenation reaction occurs to generate fulleromorpholine and fullerooxazepane derivatives. When a tethered furan ring exists, a further intramolecular [4 + 2] reaction with the neighboring double bond occurs to furnish the cis-1 products. In the case of 4-/5-amino alcohols, methanofullerenes linking with cyclic amides are obtained through cyclic enamine intermediates.

12.
Environ Geochem Health ; 39(4): 865-877, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27435489

ABSTRACT

Phthalic acid esters (PAEs) are widely used as plasticizers and in consumer products, which may enter the environment and present risks to human health. U.S. EPA classifies six PAEs as priority pollutants, which could be accumulated in street dust at the interface of atmosphere, biosphere and geosphere. This study collected a total of 58 street dust samples from Xi'an City in Northwest China and analyzed for concentrations of the priority PAEs. Composition, distribution, sources and health risk of the PAEs were further examined. All the priority PAEs were detected in the street dust. The concentrations of individual PAEs varied between not detected and 183.19 mg/kg. The sum of the 6 priority PAEs (∑6PAEs) ranged from 0.87 to 250.30 mg/kg with a mean of 40.48 mg/kg. The most abundant PAEs in the street dust were di-n-butyl phthalate and di (2-ethylhexyl) phthalate (DEHP). Higher concentrations of ∑6PAEs in the street dust were found in the south and west parts of Xi'an City as well as its urban center, which were possibly attributed to the prevailing northerly Asian winter monsoon. The PAEs in the street dust originated mainly from wide application of plasticizers as well as cosmetics and personal care products. The main pathways of human exposure to PAEs in the street dust were ingestion and dermal adsorption of dust particles. The non-cancer risk of human exposure to PAEs in the street dust was relatively low, while the risk to children was higher than that to adults. The cancer risk of human exposure to DEHP in the street dust was lower than the standard limit value of 10-6.


Subject(s)
Cities , Dust/analysis , Esters/analysis , Phthalic Acids/analysis , Adult , Child , China , Dibutyl Phthalate/analysis , Dibutyl Phthalate/toxicity , Diethylhexyl Phthalate/analysis , Diethylhexyl Phthalate/toxicity , Esters/chemistry , Esters/toxicity , Humans , Phthalic Acids/chemistry , Phthalic Acids/toxicity
13.
Biosci Biotechnol Biochem ; 80(5): 823-32, 2016 May.
Article in English | MEDLINE | ID: mdl-26873572

ABSTRACT

Fluoroacetamide (Mw = 77.06) is a lethal rodenticide to humans and animals which is still frequently abused in food storage somewhere in China. The production of antibodies for fluoroacetamide is difficult due to its high toxicity to animals, which limits the application of immunoassay method in poison detection. In this work, aptamers targeting N-fluoroacetyl glycine as an analog of fluoroacetamide were selected by a specific systematic evolution of ligands by exponential enrichment (SELEX) strategy. The binding ability of the selected aptamers to fluoroacetamide was identified using surface plasmon resonance (SPR)-based assay. The estimated KD values in the low micromolar range showed a good affinity of these aptamers to the target. Our work verified that the SELEX strategy has the potential for developing aptamers targeted to small molecular toxicants and aptamers can be employed as new recognition elements instead of antibodies for poison detection.


Subject(s)
Aptamers, Nucleotide/chemistry , Biological Assay , DNA, Single-Stranded/chemistry , Fluoroacetates/isolation & purification , Glycine/analogs & derivatives , Rodenticides/isolation & purification , Animals , Aptamers, Nucleotide/chemical synthesis , Base Sequence , DNA, Single-Stranded/chemical synthesis , Glycine/chemistry , Humans , Ligands , Molecular Mimicry , Nucleic Acid Conformation , SELEX Aptamer Technique , Sensitivity and Specificity , Sequence Alignment , Serum Albumin, Bovine/chemistry , Surface Plasmon Resonance
14.
Environ Geochem Health ; 38(2): 483-96, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26093661

ABSTRACT

Concentrations of potentially toxic elements (PTEs As, Ba, Co, Cr, Cu, Mn, Ni, Pb, Sr, V, Zn and Mo) in smaller than 100-µm street dust particles from Xining, a typical valley-city in northwestern China, were determined using X-ray fluorescence spectrometry, and their potential risks to local ecosystem and human health were assessed using potential ecological risk index and health risk model. The results indicate that the concentration of As, Ba, Co, Cr, Cu, Mn, Ni, Pb, Sr, V, Zn and Mo in the smaller than 100-µm street dust particles from Xining ranges from 0.8 to 11.1, 339.4 to 767.7, 27.2 to 110.2, 185.7 to 5134.5, 15.1 to 115.2, 150.1 to 623.5, 16.8 to 74.1, 24.4 to 233.0, 169.9 to 475.7, 47.4 to 96.8, 33.1 to 231.1 and 0.2 to 4.3 mg kg(-1), with an arithmetic mean of 3.6, 415.6, 50.1, 573.0, 40.6, 409.1, 22.6, 52.7, 257.8, 57.1, 108.6 and 2.5 mg kg(-1), respectively. Compared to the background value of local soil, the smaller than 100-µm street dust particles from Xining have elevated concentrations of Co, Cr, Cu, Pb, Zn, Sr and Mo. The contamination levels of Ba, Co, Cr, Cu, Pb, Zn, Sr and Mo are higher than As, Mn, Ni and V. The comprehensive potential ecological risk levels of PTEs were moderate to considerable. The non-carcinogenic risks of PTEs studied on children and adults due to dust exposure are limited except for Cr to children. Cr in the dust may pose a potential health risk to children; this should draw more attention.


Subject(s)
Particulate Matter/toxicity , China , Dust , Environmental Exposure , Humans , Particulate Matter/analysis , Risk Assessment , Spectrometry, X-Ray Emission
15.
J Radiol Prot ; 36(2): N26-33, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27122204

ABSTRACT

The activity concentration of natural radionuclides in the sediment of a reservoir near an industrial park of northwest China was determined using gamma ray spectrometry. The activity concentrations of (226)Ra, (232)Th and (40)K in the investigated samples range from 30.2 to 37.5, 56.5 to 79.8 and 785.6 to 940.3 Bq kg(-1) with an average of 33.2, 71.8 and 866.2 Bq kg(-1), respectively, which are higher than the corresponding activity concentrations in the control sample. Radium equivalent activity, external hazard index, internal hazard index, indoor air absorbed dose rate and annual effective dose rate were calculated to assess the radiation hazards associated with the use of this sediment in the construction of dwellings. It was concluded that the radiation levels in the reservoir sediment do not give rise to radiological health concerns and the sediment can be safely used in the construction of buildings.


Subject(s)
Geologic Sediments/chemistry , Radiation Monitoring/methods , Radioisotopes/analysis , China , Industry , Potassium Radioisotopes/analysis , Radium/analysis , Spectrometry, Gamma , Thorium/analysis
16.
Org Biomol Chem ; 13(31): 8405-10, 2015 Aug 21.
Article in English | MEDLINE | ID: mdl-26166711

ABSTRACT

The Cu(OAc)2-promoted reaction of C60 with easily available primary amines allows the concise preparation of aziridinofullerenes. Both alkyl and aryl amines are suitable in this reaction. Moreover, the Cu(OAc)2-promoted reaction of C60 with diamines affords C60-fused cyclic 1,2-diaminated fullerenes.

17.
J Org Chem ; 79(23): 11774-9, 2014 Dec 05.
Article in English | MEDLINE | ID: mdl-25390045

ABSTRACT

The Lewis base-catalyzed double nucleophilic substitution reaction of N-tosylaziridinofullerene with various ureas allows the easy preparation of fulleroimidazolidinones with a high tolerance for functional groups. Alkyl-substituted ureas show better reactivity than aryl-substituted ureas.


Subject(s)
Aziridines/chemical synthesis , Fullerenes/chemistry , Imidazolidines/chemical synthesis , Lewis Bases/chemistry , Urea/chemistry , Aziridines/chemistry , Catalysis , Imidazolidines/chemistry , Models, Molecular , Molecular Structure
18.
J Org Chem ; 79(23): 11744-9, 2014 Dec 05.
Article in English | MEDLINE | ID: mdl-25369264

ABSTRACT

BF3·Et2O-catalyzed double nucleophilic substitution reaction of N-tosylaziridinofullerene with sulfamides has been exploited for the easy preparation of cyclic sulfamide-fused fullerene derivatives. Moreover, the Lewis base catalyzed double amination of N-tosylaziridinofullerene, with amidines as the diamine source, is demonstrated for the first time. The present methods provide new routes to cyclic 1,2-diaminated [60]fullerenes.

19.
Environ Res ; 128: 27-34, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24407476

ABSTRACT

Concentrations, pollution and health risks of metals in dust from nursery schools in Xi'an, China were determined. In comparison with local soil, dust samples have elevated metals concentrations except for Mn. The results indicate no distinct pollution of Mn, Ni, As and Ba in the dust, while Cu, Co and Zn are moderate pollution, Pb is significant pollution, and Cr with large pollution range. Most samples presented moderately polluted by metals. The non-cancer risks of the studied metals are within the safe range, and the cancer risks of As, Co, Cr and Ni are also within the currently acceptable range.


Subject(s)
Dust/analysis , Environmental Pollutants/analysis , Environmental Pollution/analysis , Metals, Heavy/analysis , Schools, Nursery/statistics & numerical data , Child, Preschool , China , Environmental Pollution/statistics & numerical data , Humans , Risk Assessment
20.
Ecotoxicol Environ Saf ; 106: 154-63, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24840878

ABSTRACT

The concentrations of toxic metals As, Co, Cr, Cu, Mn, Ni, Pb, V and Zn in street dust of Tongchuan, China were determined by wavelength dispersive X-ray fluorescence spectrometry. The risk of the analyzed metals to urban ecosystem and human health were evaluated by potential ecological risk index and human exposure model, respectively. The results show that, in comparison with Shaanxi soil, dust samples have elevated metal concentration as a whole expect for As, Mn, V and Ni. The assessment results of ecological risk indicate that the ecological risks of As, Cr, Mn, Ni, Cu, V and Zn in the dust were in the low level, while Pb and Co presented low to moderate level. Health risk assessment shows that ingestion was the main exposure route of all analyzed toxic metals in street dust to children and adults. The non-cancer risks of the studied metals to children and adults were within the safe range, and the cancer risks of As, Co, Cr and Ni were also within the currently acceptable range.


Subject(s)
Cities , Dust/analysis , Environmental Monitoring , Metals, Heavy/analysis , Adult , Child , China , Humans , Industry , Models, Theoretical , Risk Assessment
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