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1.
Water Res ; 250: 121076, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38171178

RESUMO

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


Assuntos
Metais Pesados , Oligoelementos , Criança , Adulto , Humanos , Monitoramento Ambiental/métodos , Oligoelementos/análise , Ecossistema , Cádmio , Medição de Risco , Metais Pesados/análise , China , Receptores de Antígenos de Linfócitos T
2.
Se Pu ; 41(8): 698-706, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-37534557

RESUMO

Short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) have attracted significant attention because of their persistence, biotoxicity, bioaccumulation, and long-range migration. Given their worldwide detection in a variety of environmental matrices, concerns related to the high exposure risks of SCCPs and MCCPs to humans have grown. Thus, knowledge of the contamination patterns of SCCPs and MCCPs and their distribution characteristics in the vivo exposure of humans is of great importance. However, little information is available on the contamination of SCCPs and MCCPs in human blood/plasma/serum, mainly because of the difficulty of sample preparation and quantitative analysis. In this study, a new blood sample pretreatment method based on Percoll discontinuous density gradient centrifugation was developed to separate plasma, red blood cells, white blood cells, and platelets from human whole blood. A series of Percoll sodium chloride buffer solutions with mass concentrations of 1.095, 1.077, and 1.060 g/mL were placed in a centrifuge tube from top to bottom to establish discontinuous density gradients. The dosage for each density gradient was 1.5 mL. Human whole blood samples mixed with 0.85% sodium chloride aqueous solution were then added to the top layer of the Percoll sodium chloride solution. After centrifugation, the whole blood was separated into four components. The plasma was located at the top layer of the centrifuge tube, whereas the platelets, white blood cells, and red blood cells were retained at the junction of the various Percoll sodium chloride solutions. The sampling volume of human whole blood and incubation time were optimized, and results indicated that an excessively long incubation time could lead to hemolysis, resulting in a decrease in the recoveries of SCCPs and MCCPs. Therefore, a sampling volume of 1.5 mL and incubation time of 10 min at 4 ℃ were adopted. The cells of the blood components were further broken and extracted by ultrasonic pretreatment, followed by multilayer silica gel column chromatography for lipid removal. The use of 80 mL of n-hexane-dichloromethane (1∶1, v/v) and 50 mL of dichloromethane as the elution solvents (collected together) for the gel column separated the SCCPs and MCCPs from the lipid molecules in the blood samples. Gas chromatography-electron capture negative ion-low resolution mass spectrometry (GC-ECNI-LRMS) was used to determine the SCCPs and MCCPs. Quantification using the corrected total response factor with degrees of chlorination was achieved with linear corrections (R2=0.912 and 0.929 for the SCCPs and MCCPs, respectively). The method detection limits (MDLs) for the SCCPs and MCCPs were 1.57 and 8.29 ng/g wet weight (ww, n=7), respectively. The extraction internal standard recoveries were 67.0%-126.6% for the SCCPs and 69.5%-120.5% for the MCCPs. The developed method was applied to determine SCCPs and MCCPs in actual human whole blood samples. The contents of SCCPs and MCCPs were 10.81-65.23 and 31.82-105.65 ng/g (ww), respectively. Red blood cells exhibited the highest contents of CPs, followed by plasma, white blood cells, and platelets. The proportions of SCCPs and MCCPs in red blood cells and plasma were 70% and 66%, respectively. In all four components, the MCCP contents were higher than the SCCP contents, and the ratios of MCCPs to SCCPs ranged from 1.04 to 3.78. Similar congener patterns of SCCPs and MCCPs were found in the four components of human whole blood. C10-CPs and C14-CPs were predominantly observed in the SCCPs and MCCPs, respectively. In summary, a simple and efficient method was proposed to determine low concentrations of SCCPs and MCCPs in human blood with high sensitivity and selectivity. This method can meet requirements for the quantitative analysis of SCCPs and MCCPs in human blood components, thereby providing technical support for human health risk assessment.


Assuntos
Hidrocarbonetos Clorados , Parafina , Humanos , Parafina/análise , Cloreto de Metileno/análise , Hidrocarbonetos Clorados/análise , Elétrons , Cloreto de Sódio/análise , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lipídeos , China
3.
Front Pharmacol ; 14: 1181622, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37405054

RESUMO

Background: Post-infarction chronic heart failure is the most common type of heart failure. Patients with chronic heart failure show elevated morbidity and mortality with limited evidence-based therapies. Phosphoproteomic and proteomic analysis can provide insights regarding molecular mechanisms underlying post-infarction chronic heart failure and explore new therapeutic approaches. Methods and results: Global quantitative phosphoproteomic and proteomic analysis of left ventricular tissues from post-infarction chronic heart failure rats were performed. A total of 33 differentially expressed phosphorylated proteins (DPPs) and 129 differentially expressed proteins were identified. Bioinformatic analysis indicated that DPPs were enriched mostly in nucleocytoplasmic transport and mRNA surveillance pathway. Bclaf1 Ser658 was identified after construction of Protein-Protein Interaction Network and intersection with Thanatos Apoptosis Database. Predicted Upstream Kinases of DPPs based on kinase-substrate enrichment analysis (KSEA) app showed 13 kinases enhanced in heart failure. Proteomic analysis showed marked changes in protein expression related to cardiac contractility and metabolism. Conclusion: The present study marked phosphoproteomics and proteomics changes in post-infarction chronic heart failure. Bclaf1 Ser658 might play a critical role in apoptosis in heart failure. PRKAA1, PRKACA, and PAK1 might serve as potential therapeutic targets for post-infarction chronic heart failure.

4.
Front Neurosci ; 17: 1174455, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152604

RESUMO

Purpose: This study investigated the functional outcomes of patients with chronic heart failure (CHF) after physiological ischemic training (PIT), identified the optimal PIT protocol, evaluated its cardioprotective effects and explored the underlying neural mechanisms. Methods: Patients with CHF were randomly divided into experimental group (n = 25, PIT intervention + regular treatment) and control group (n = 25, regular treatment). The outcomes included the left ventricular ejection fraction (LVEF), brain natriuretic peptide (BNP) and cardiopulmonary parameters. LVEF and cardiac biomarkers in CHF rats after various PIT treatments (different in intensity, frequency, and course of treatment) were measured to identify the optimal PIT protocol. The effect of PIT on cardiomyocyte programmed cell death was investigated by western blot, flow cytometry and fluorescent staining. The neural mechanism involved in PIT-induced cardioprotective effect was assessed by stimulation of the vagus nerve and muscarinic M2 receptor in CHF rats. Results: LVEF and VO2max increased while BNP decreased in patients subjected to PIT. The optimal PIT protocol in CHF rats was composed of five cycles of 5 min ischemia followed by 5 min reperfusion on remote limbs for 8 weeks. LVEF and cardiac biomarker levels were significantly improved, and cardiomyocyte apoptosis was inhibited. However, these cardioprotective effects disappeared after subjecting CHF rats to vagotomy or muscarinic M2 receptor inhibition. Conclusion: PIT improved functional outcomes in CHF patients. The optimal PIT protocol required appropriate intensity, reasonable frequency, and adequate treatment course. Under these conditions, improvement of cardiac function in CHF was confirmed through cardiomyocyte apoptosis reduction and vagus nerve activation.

5.
Sci Total Environ ; 858(Pt 1): 159875, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36461561

RESUMO

Short and medium chain chlorinated paraffins (SCCPs and MCCPs) attract increasing attentions due to their persistence, long-range transport capacity. Their gas/particle partitioning from the production emission source, the effects to the ambient environment and exposure for employees are worth revealing. Polyurethane foam based passive air samplers (PUF-PAS) was deployed to determine the environmental levels of SCCPs (63.4-719.7 ng/m3) and MCCPs (151.6-1009.2 ng/m3) in the gas-phase and particle-phase both in the outdoor air in a CP production plant and the indoor air in the workshops. Extremely high SCCPs were found in the chlorination workshop and outdoor samples nearby, attributing to the release during the production. In the workshops, dramatically higher SCCP concentrations were determined than outdoors. SCCPs and MCCPs predominated in the gas-phase with a proportion >80 %. C10-CPs and C14-CPs were dominated with a proportion higher than 20 % and 50 %, respectively. Significant correlations between log Kp' and log PL0 and log KOA were observed in the outdoor air in a CP production plant and the indoor air in the workshops, respectively. A multivariate mechanism based on adsorption by organic matters and influenced by absorption processes might determine the gas/particle partitioning of CPs in the production source area. Two scenarios of occupational exposure i.e. working in the workshops and working outdoors were considered. Higher occupational exposure via inhalation to MCCPs was found for employees than SCCPs in the workshops, which was estimated to be 137.1 ng/kg/day at a worst case. No obvious adverse effects were observed for occupational employees in this CP production plant.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Exposição Ocupacional , Humanos , Parafina , Adsorção , Halogenação
6.
Comput Math Methods Med ; 2022: 2204981, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237338

RESUMO

OBJECTIVE: To elucidate the therapeutic efficacy of needle-warming moxibustion (NWM) combined with hyperbaric oxygen therapy (HBOT) in the treatment of patients with ischemic stroke and its effect on neurological function. METHODS: One hundred patients with ischemic stroke admitted to the Xuzhou Medical University Affiliated Hospital of Lianyungang from January 2019 to July 2021 were enrolled. Among them, 45 patients treated with NWM were set as the control group, and the rest 55 patients treated by NWM combined with HBOT were included in the research group. The curative effect, neurological deficit score, activity of daily living (ADL), balance ability, and the levels of serum proinflammatory factors in both groups were observed and recorded. Of them, the neurological deficit of patients was evaluated by the National Institutes of Health Stroke Scale (NHISS), the ADL ability was determined by the Barthel index score, and the balance ability was assessed by the Berg balance scale. RESULTS: The total effective rate of the research group was higher than that of the control group. Better ADL and balance ability and milder neurologic impairment were determined in the research group compared with the control group. After treatment, the secretion levels of proinflammatory factors such as C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-8 (IL-8) in the serum of patients in the research group were statistically lower than those before treatment and the control group. CONCLUSIONS: NWM combined with HBOT is effective in the treatment of patients with ischemic stroke, which can not only improve patients' neurological function, ADL, and balance ability but also inhibit serum inflammatory reactions.


Assuntos
Oxigenoterapia Hiperbárica , AVC Isquêmico/terapia , Moxibustão/métodos , Atividades Cotidianas , Idoso , Terapia Combinada , Biologia Computacional , Feminino , Humanos , Mediadores da Inflamação/sangue , AVC Isquêmico/sangue , AVC Isquêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Equilíbrio Postural/fisiologia
7.
Chemosphere ; 288(Pt 1): 132488, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34624346

RESUMO

Organic species in fine particulate matter (PM2.5) may exhibit significant health risks. The level, composition and sources of PM2.5-bound organic pollutants are temporally and spatially highly variable. In this study, the pollution characteristics and health risks of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs) and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in PM2.5 of Dalian were investigated. PM2.5-bound organic pollutants in Dalian were generally lower than other regions in China and other countries, significant seasonal changes were observed, higher levels appeared in winter than in summer. Concentrations of 16 PAHs were 2.07 ng/m3 and 13.99 ng/m3 in summer and winter, respectively. PAHs with 4-ring and 5-ring were the dominant components. Diagnostic analysis and principal component analysis (PCA) indicated that PAHs mainly originate from petroleum emissions and combustion. Concentrations of PCDD/Fs, PCBs and PCNs in PM2.5 ranged from 0.05 to 3.27, 0.04-0.65 and 0.05-1.42 pg/m3, respectively. PCDD/Fs and PCBs were mainly consisted of high-chlorinated homologues during the sampling period. High-chlorinated PCNs were dominated only in winter, while low-chlorinated PCNs were dominated in summer, industrial thermal activity was one of the main sources of PCNs. The high correlation coefficients of the concentration of PAHs, PCBs, PCNs, and PCDD/Fs with that of SO2 indicated that combustion sources contributed more to PM2.5-bound organic pollutants than that of motor vehicle emissions. The incremental lifetime cancer risk induced by PM2.5-bound POPs is relatively lower in Dalian than other regions.


Assuntos
Poluentes Atmosféricos , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Naftalenos/análise , Material Particulado , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
8.
ACS Omega ; 6(47): 31955-31963, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34870018

RESUMO

Polymer sponges with molecular recognition provide a facile approach to water purification and industrial separation with easy operation. Herein, a thiolated polyethyleneimine (PEI)-based polymer sponge was prepared through cryo-polymerization of PEI, followed by grafting of PEI and then post-modification of the amine functionalities present within the hyperbranched structure with methyl mercaptoacetate, which afford high density of thiol functional groups on the surface of the sponge. The developed sponge was characterized by scanning electron microscopy and element analysis, and the adsorption kinetic and isotherm studies were conducted in detail. The sponge presents a remarkable maximum adsorption capacity of 2899.7 mg/g, which can be attributed to its high density of thiol functionalities. The sponge also shows excellent selectivity toward Hg2+ against other metal ions and natural organic matter, indicating its great potential in removing mercury from real water bodies. In addition, the sponge can be chemically regenerated and exhibits good reusability, which decreases the economic and environmental impacts. Hence, the high removal efficiency, high selectivity toward mercury, and good reusability of the sponge material highlight it as a promising sorbent for mercury removal in water pollution treatment.

9.
Planta ; 254(6): 110, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34716824

RESUMO

MAIN CONCLUSION: Soybean phosphorous efficiency QTLs were identified and candidate genes were predicted using chlorophyll fluorescence parameters through GWAS and RNA-seq. Phosphorus (P) is an essential nutrient element for crop growth and development, lack of P uptake seriously affects yield in various crops. Photosynthesis is the basis of crop production, while it is very sensitive to P deficiency. It is of great importance to study the genetic relationship between photosynthesis and P efficiency to provide genetic insight for soybean improvement. In this study, a genome-wide association study (GWAS) was performed using 292,035 SNPs and the ratios of four main chlorophyll fluorescence parameters of 219 diverse soybean accessions under P deficiency and normal P across three experiments. In total, 52 SNPs in 12 genomic regions were detected in association with the four main chlorophyll fluorescence parameters under sufficient or deficient P levels. Combined it with RNA-seq analysis, we predicted three candidate genes for the significant genomic regions. For example, the expression level of the candidate gene (Glyma.18g092900) in P deficiency tolerant accession was three times higher than that of P deficiency sensitive one under phosphorous deficiency condition. This study provides insight into genetic links between photosynthetic and phosphorous efficiency and further functional analysis will provide valuable information for understanding the underlying genetic mechanism to facilitate marker-assisted breeding in soybean.


Assuntos
Estudo de Associação Genômica Ampla , Glycine max , Clorofila , Fósforo , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único/genética , RNA-Seq , Glycine max/genética
10.
Polymers (Basel) ; 12(9)2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32937903

RESUMO

Poly(2-(diethylamino)ethyl methacrylate-co-divinylbenzene) (poly(DEAEMA-co-DVB)) microspheres with mixed-mode weak anion-exchange (WAX) character were successfully fabricated for the first time via facile one-step Pickering emulsion polymerization. The obtained poly(DEAEMA-co-DVB) particles had good spherical geometry, uniform particle size in the range of 30-40 µm, a large specific surface area of 575 m2/g, and a pore size range of 5-30 nm, according to the SEM and nitrogen adsorption-desorption results. Using these mixed-mode WAX microspheres as packing material, a reliable and robust analytical method based on solid phase extraction and high performance liquid chromatography with ultraviolet detection (SPE-HPLC-UV) was developed for simultaneous determination of six strongly and weakly acidic nonsteroidal anti-inflammatory drugs (NSAIDs, niflumic acid, diflunisal, naproxen, ketoprofen, mefenamic acid, and diclofenac) in reservoir water. Under optimized conditions, it was applicable to preconcentrate up to 500 mL of reservoir water samples on the WAX cartridges with satisfying recoveries (88-96%) for all the NSAIDs tested. The limits of detection were in the range of 0.002-0.025 µg L-1, respectively. Our results showed that the developed mixed-mode WAX poly(DEAEMA-co-DVB) phase containing a tertiary amine with a pKa value of approximately 10.7 could be used for simultaneous clean-up and preconcentration of strongly and weakly acidic organic pollutants in real environmental water, which could not be achieved by single use of quaternary ammonium strong anion-exchange phase or weaker primary and secondary amine anion-exchange.

11.
Cell Mol Biol (Noisy-le-grand) ; 66(3): 39-47, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32538745

RESUMO

This study was designed to investigate the expressions and roles of MMP-9 and HMGB1 in peripheral blood of patients with epilepsy and their relationship with the cognitive function and to explore factors affecting the prognosis of epilepsy patients. A total of 127 patients with epilepsy were collected in the study group and 120 healthy subjects receiving a physical examination at the same time were collected in the control group. The MMP-9 and HMGB1 expressions and their diagnostic value for epilepsy were compared between the two groups. The relationship between MMP-9 and HMGB1 expression levels and the clinical-pathological features and the Mini-mental State Evaluation Scale (MMSE) of patients from the study group were also analyzed. The serum levels of MMP-9 and HMGB1 in the study group were significantly higher than those in the control group (P< 0.001), and were greatly decreased after the treatment (P<0.001). The ROC curve showed that MMP-9 and HMGB1 combined detection had a good diagnostic efficiency for epilepsy. MMP-9 was much related to the type and disease duration of epilepsy (P< 0.05). HMGB1 was significantly associated with disease duration, seizure, and previous treatment history of epilepsy (P< 0.050). According to the Pearson correlation coefficient analysis, the expressions of MMP-9 and HMGB1 were negatively correlated with MMSE scores of the study group (P< 0.001). Logistic regression analysis showed that the duration of disease, seizures, MMP-9, and HMGB1 were independent risk factors for the prognosis of epilepsy. The expression levels of MMP-9 and HMGB1 in peripheral blood of patients with epilepsy are significantly increased, and negatively correlated with neurological function scores. They have potential involvement in the occurrence and development of epilepsy, which makes them significant for the diagnosis and treatment of epilepsy in the future.


Assuntos
Epilepsia/sangue , Epilepsia/diagnóstico , Proteína HMGB1/sangue , Metaloproteinase 9 da Matriz/sangue , Adulto , Idoso , Cognição/efeitos dos fármacos , Cognição/fisiologia , Epilepsia/tratamento farmacológico , Epilepsia/psicologia , Feminino , Proteína HMGB1/metabolismo , Humanos , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Análise de Regressão , Fatores de Risco , Convulsões
12.
J Crit Care ; 56: 249-256, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31986368

RESUMO

PURPOSE: The aim of this study was to explore the effects of an enteral nutrition (EN) feeding protocol in critically ill patients. METHODS: This was a prospective multi-center before-after study. We compared energy related and prognostic indicators between the control group (pre-implementation stage) and intervention group (post-implementation stage). The primary endpoint was the percentage of patients receiving EN within 7 days after ICU admission. RESULTS: 209 patients in the control group and 230 patients in the intervention group were enrolled. The implementation of the EN protocol increased the percentage of target energy reached from day 3 to day 7, and the difference between two groups reached statistical significance in day 6 (P = .01) and day 7 (P = .002). But it had no effects on proportion of patient receiving EN (P = .65) and start time of EN (P = .90). The protocol application might be associated with better hospital survival (89.1% vs 82.8%, P = .055) and reduce the incidence of EN related adverse (P = .004). There was no difference in ICU length of stay, duration of mechanical ventilation and ICU cost. CONCLUSION: The implementation of the enteral feeding protocol is associated with improved energy intake and a decreased incidence of enteral nutrition related adverse events for critically ill patients, but it had no statistically beneficial effects on reducing the hospital mortality rate. Trial registration ClinicalTrials.gov, NCT02976155. Registered November 29, 2016- Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02976155.


Assuntos
Estado Terminal/mortalidade , Nutrição Enteral/métodos , Unidades de Terapia Intensiva , Tempo de Internação , Respiração Artificial/efeitos adversos , China , Estudos Controlados Antes e Depois , Ingestão de Energia , Feminino , Mortalidade Hospitalar , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Admissão do Paciente , Prognóstico , Estudos Prospectivos
13.
Se Pu ; 37(11): 1228-1234, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642277

RESUMO

A method based on thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) was developed for the simultaneous analysis of 67 volatile organic compounds (VOCs) in ambient air. In this study, the adsorption effects of five kinds of stainless steel sorbent tubes for 78 VOCs were compared. The results revealed that a multisorbent bed with Carbograph 1TD and Tenax TA shows good adsorption effect for the 67 target compounds. The breakthrough rates of all the target compounds were less than 10% when high-purity helium gas was continuously purged for 45 min at 30 mL/min. The analytes included aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons, and oxygen-containing volatile organic compounds. The thermal desorption conditions for the determination of the target substances were optimized. In the range 5-100 ng, the chromatographic response of the target compounds had a good linear relationship with their corresponding amounts, and the correlation coefficient (r) was between 1.0000 and 0.9977. The method detection limits (MDLs) were 0.3-2.4 ng or 0.3-2.4 µg/m3, as calculated by a 1 L sampling volume. The method was validated by means of recovery experiments (n=7) with the addition of 20 ng standard samples. The recoveries of all the target compounds were in the range of 81.6%-114.9%, and their relative standard deviations (RSDs) were in the range of 1.2%-10.2%. The VOCs present in the air in a carriage were detected using this method. The 19 target compounds included esters, halogenated alkanes, halogenated olefins, and aromatic substances, whose concentrations ranged from 1.1 to 84.1 µg/m3. These results indicated that our method is accurate, reliable, and sensitive, and can allow for accurate quantification of the 67 target pollutants in ambient air.

14.
Sensors (Basel) ; 19(20)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627275

RESUMO

Essential for directing conservation resources is to identify threatened vertebrate regions and diagnose the underlying causalities. Through relating vertebrates and threatened vertebrates to the rainfall-runoff chain, to the food chain, and to the human impact of urbanization, the following relationships are noticed: (i) The Earth's vertebrates generally show increasing abundance and decreasing threatened species indicator (threatened species number/species abundance) for a higher Normalized Difference Vegetation Index (NDVI) or larger city-size. (ii) Regional vertebrates reveal a notable 'U-shape profile' ('step-like jump') of threatened species indicator occurs in the moderate (high) NDVI regions in China (America). (iii) Positive/green city states emerge in China and are characterized by the lowest threatened species indicators in areas of low to moderate greenness, where the greenness trend of change during the last 30 years is about three times higher in the urbanized areas than over land. (iv) Negative/brown city states emerge in America revealing high threatened species indicators for greenness exceeding NDVI > 0.2, where similar greenness trends are of both urbanized and land areas. The occurrence of green and brown city states suggests a biodiversity change pattern characterized by the threatened species indicator declining from city regimes with high to those with low indicator values for increasing ratio of the city-over-land NDVI trends.


Assuntos
Biodiversidade , Ecossistema , Monitoramento Ambiental , Vertebrados/crescimento & desenvolvimento , Animais , China , Cidades , Clima , Humanos , Temperatura , Estados Unidos , Urbanização
15.
J Environ Sci (China) ; 80: 287-295, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30952346

RESUMO

The concentration of short-chain polychlorinated paraffins (SCCPs) in the urban air of Dalian, China was monitored from September 2016 to August 2017 with a self-developed passive sampler (PAS1) and an active high-volume sampler, simultaneously. PAS1 successfully collected the entire target SCCPs in the ambient air. Air SCCPs sampled by PAS1 were found be in the linear uptake stage during 181 days of sampling. Passive and active samples showed comparable congener profiles, and the dominant contributors of SCCPs in the two kinds of samples were similar. A significant linear correlation was observed between the total concentration of SCCPs sampled by PAS1 and active sampler in the four seasons. The passive sampling rates of the PAS1 for the gas and particulate phases of SCCPs were measured. The quantitative structure-property relationship of the sampling rate of PAS1 (Rair) for gas-phase SCCPs was studied. From the molecular point of view, Rair was mainly affected by the molecular weight and sub-cooled liquid vapor pressure of SCCPs. In general, SCCPs in the urban air of Dalian mainly existed in gas phase, lower molecular weight SCCPs primarily occurred in the gas phase, whereas higher molecular weight SCCPs were predominately adsorbed or absorbed on airborne particles. The air concentration of SCCPs in the four seasons were different, the correlation of the concentration of SCCPs in the air with the meteorology parameters was conducted. The exposure risk by intake air SCCPs of the residents around the sampling sites was evaluated according to the European risk assessment standards.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise , Parafina/análise , China , Material Particulado
16.
Sci Total Environ ; 647: 29-36, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30077852

RESUMO

To quantify how urbanization induced long-term changes have altered the evolution of urban climate, a novel eco-hydrological diagnostic is introduced and applied globally, to a developing and a developed country (China and US-America). Urban areas are (i) geographically identified by remote sensing based nighttime light, (ii) physically embedded in state spaces spanned by suitable combinations of surface energy and water fluxes comprising the rainfall-runoff chain, and (iii) dynamically characterized by the time evolution of the surface fluxes at geographically fixed locations, analyzed as trajectories in state space, and interpreted by an attribution model separating anthropogenic from climate induced causes. The results describe the long term climatological settings of urban areas in a net radiation versus dryness diagram, while the attribution of change is diagnosed in a state space spanned by energy and water excess: (i) Cities in China are characterized by a bi-modal distribution separated by the boundary between water and energy-limited (northern and southern) regimes while US-American cities are assembling unimodally on this boundary, and globally the urbanized areas are also aligned along this boundary between water and energy-limited regimes. (ii) Attribution of eco-hydrological changes of urbanized regions to climate and human-induced causes shows also basic differences between the developing and developed country: urbanization in Chinese cities is characterized by a 'wet-gets-drier' and 'dry-gets-wetter' paradigm of the climate-induced contributions, due to which cities tend towards a unimodal state as it is observed for US-American urban areas. Finally, implications for large scale city planning are discussed in the outlook.

17.
Environ Sci Pollut Res Int ; 25(27): 27514-27523, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30051288

RESUMO

The concentrations of α-, ß-, and γ-hexabromocyclododecane diastereomers (HBCDs) in gas phase and particulate phase of Dalian urban air, China, were monitored from September 2016 to August 2017 with high-volume active sampler. The total concentration of ∑HBCDs (gas phase + particulate phase) ranged from 15.47 to 43.57 pg m-3, with an average of 27.07 pg m-3, and 73.39-96.76% of the total HBCDs were found in the particulate phase. No matter in gas phase or in particulate phase, α-HBCD was the predominant component in all, and there was a good negative correlation between the relative contribution of α-HBCD to ∑HBCDs and that of γ-HBCD to ∑HBCDs. The average ratios of the air concentration of α-HBCD to γ-HBCD were comparable with those found in decorative polystyrene, which indicated that HBCDs in outdoor air of Dalian probably came from indoor air and ventilation air from inside of buildings coupled with the already present contamination in background air. There were clear seasonal differences in the HBCD concentrations. Spearman's rank correlation analysis between the concentrations of HBCDs with meteorological parameters was conducted. The exposure risk of HBCDs was evaluated, which illustrated that the estimated exposure of HBCDs via the outdoor air in Dalian was well below the reference doses (200 ng kg-1 bw day-1) derived by the US National Research Council.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Bromados/análise , Material Particulado/análise , China , Cidades , Monitoramento Ambiental
18.
Oncol Lett ; 15(5): 7403-7408, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29731892

RESUMO

Chitinase-3-like-1 protein (YKL-40), a member of the mammalian chitinase-like glycoproteins, serves a key role in the pathogenesis of rectal cancer. The present study examined the antitumor effect of theophylline, a pan-chitinase inhibitor, in rectal cancer in vitro and investigated the mechanism by which it acted. SW480 cell lines were treated with varying theophylline concentrations (10-2, 10-3, 10-4 and 10-5 mol/l). An MTT assay was used to observe cell proliferation and identify the optimal theophylline concentration. Western blotting was used to analyze YKL-40 expression. The cell cycle distribution of SW480 cell lines treated with theophylline was measured by flow cytometry. The angiopoietin-2 expression level was measured by ELISA. The expression levels of YKL-40 were evidently decreased in theophylline-treated SW480 cell lines. The proliferation of SW480 cells was inhibited following theophylline treatment, which was associated with G1 phase cell cycle arrest and a decrease in the expression of angiopoietin-2. The mechanism of theophylline action may involve the downregulation of YKL-40 expression, arrest of the cell cycle at G1 phase and inhibition of angiopoietin-2 expression. These results provide a rationale for the potential use of anti-YKL-40 and anti-angiogenic strategies in treating rectal cancer.

19.
Sci Rep ; 8(1): 7702, 2018 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-29769593

RESUMO

East Asia has experienced strong warming since the 1960s accompanied by an increased frequency of heat waves and shrinking glaciers over the Tibetan Plateau and the Tien Shan. Here, we place the recent warmth in a long-term perspective by presenting a new spatially resolved warm-season (May-September) temperature reconstruction for the period 1-2000 CE using 59 multiproxy records from a wide range of East Asian regions. Our Bayesian Hierarchical Model (BHM) based reconstructions generally agree with earlier shorter regional temperature reconstructions but are more stable due to additional temperature sensitive proxies. We find a rather warm period during the first two centuries CE, followed by a multi-century long cooling period and again a warm interval covering the 900-1200 CE period (Medieval Climate Anomaly, MCA). The interval from 1450 to 1850 CE (Little Ice Age, LIA) was characterized by cooler conditions and the last 150 years are characterized by a continuous warming until recent times. Our results also suggest that the 1990s were likely the warmest decade in at least 1200 years. The comparison between an ensemble of climate model simulations and our summer reconstructions since 850 CE shows good agreement and an important role of internal variability and external forcing on multi-decadal time-scales.

20.
Se Pu ; 35(10): 1080-1085, 2017 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-29048806

RESUMO

A high performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method was developed for the determination of hexabromocyclododecanes (HBCDs) in ambient air samples. The samples were extracted by Soxhlet extractor with hexane, then purified on the composite gel column. At first, the interfering substances were rinsed with 50 mL hexane and 100 mL hexane-dichloromethane (9:1, v/v), then 180 mL hexane -dichloromethane (4:1, v/v) was used to elute the targets. The compounds were separated by gradient elution with acetonitrile-methanol-water as mobile phases on a UF-ODS column (150 mm×2.1 mm, 3.0 µm). Electrospray ionization negative ion source and selective ion monitoring (SIM) mode were adopted in MS detection. The results showed that α -HBCD, ß -HBCD and γ -HBCD could be well separated, and the chromatographic peak area ratio of α -HBCD, ß -HBCD and γ -HBCD to internal standard D18- γ -HBCD with their concentrations had a good linear relationship, with the correlation coefficients (R) ≥ 0.9988. The limits of detection (LODs, S/N=3) of α -HBCD, ß -HBCD and γ -HBCD were 0.4, 0.5 and 0.4 µg/L, respectively. The limits of quantification (LOQs, S/N=10) were 1.4, 1.6 and 1.3 µg/L, respectively. The method detection limits (MDL) were 0.13, 0.17 and 0.13 pg/m3 (n=5), respectively. The recoveries of HBCDs spiked in the actual air samples were in the range of 74.8%-95.8%. It is demonstrated that the method has high sensitivity and good selectivity, and can meet the requirement of monitoring and analyzing HBCDs in air samples.

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