A Cost-Effective and Labor-Saving Method for Detecting Human Leukocyte Antigen B27 Status via Sequence-Encoded Fluorescence Amplification Assay.

Identification of human leukocyte antigen B27 (HLA-B27) by flow cytometry (FCM) has been widely applied in clinical practice for auxiliary diagnosis of ankylosing spondylitis (AS). However, FCM requires freshly prepared samples and relies on expensive equipment, reagents, and an experienced operator. To provide a cheaper and more convenient method for HLA-B27 detection, we proposed a new method termed sequence-encoded fluorescence amplification assay (SEFA), which specially recognized sequences of HLA-B27 gene (HLA-B∗27) covering current common subtypes in a single closed tube. SEFA could detect as low as 10 pg (equal to 3 copies) genomic DNA per reaction and distinguish HLA-B∗27 from other HLA-B alleles with highly similar sequences. A total of 288 clinical samples were tested by SEFA, including 181 patients with AS and 107 healthy controls. Compared with the detection results from FCM, two controversial samples of patients with AS were obtained and further confirmed to be consistent with SEFA by Sanger sequencing, indicating that this method was more accurate than FCM. Moreover, SEFA could detect HLA-B27 status by using supernatant from crude extract of 10-µL blood without commercial reagents. Overall, SEFA has the potential to be an alternative for HLA-B27 identification with the advantage of convenience and low cost, especially suitable for early diagnosis of AS in areas with limited medical resources.

Screening of organophosphate esters in different indoor environments: Distribution, diffusion, and risk assessment.

ANALYSIS: of air conditioner (AC) filter dust can reveal the level of organophosphate ester (OPE) pollution in indoor environments, but comprehensive research on this topic remains lacking. This study combined non-targeted and targeted analysis to screen and analyze 101 samples of AC filter dust, settled dust, and air obtained in 6 indoor environments. Phosphorus-containing organic compounds account for a large proportion of the organic compounds found in indoor environments, and OPEs might be the main pollutants. Using toxicity data and traditional priority polycyclic aromatic hydrocarbons for toxicity prediction of OPEs, 11 OPEs were prioritized for further quantitative analysis. The concentration of OPEs in AC filter dust was highest, followed in descending order by that in settled dust and that in air. The concentration of OPEs in AC filter dust in the residence was two to seven times greater than that in the other indoor environments. More than 56% of the OPEs in AC filter dust showed significant correlation, while those in settled dust and air were weakly correlated, suggesting that large amounts of OPEs collected over long periods could have a common source. Fugacity results showed that OPEs were transferred easily from dust to air, and that dust was the main source of OPEs. The values of both the carcinogenic risk and the hazard index were lower than the corresponding theoretical risk thresholds, indicating low risk to residents through exposure to OPEs in indoor environments. However, it is necessary to remove AC filter dust in a timely manner to prevent it becoming a pollution sink of OPEs that could be rereleased and endanger human health. This study has important implications for comprehensive understanding of the distribution, toxicity, sources, and risks of OPEs in indoor environments.

Utility of vector flow mapping technology in quantitative assessment of carotid wall shear stress in hypertensive patients: A preliminary study.

Background: Blood flowing in the arterial lumen acts on the surface of the vessel wall to form wall shear stress (WSS). To date, there has been limited research on the utility of non-invasive technology in the accurate quantification of carotid WSS in patients with hypertension (HP). Objective: The present study aimed to explore the usage of vascular vector flow mapping (VFM) in the quantitative assessment of carotid WSS in hypertensive patients at an early stage and to validate its clinical utility. Methods: A total of 50 individuals confirmed without carotid plaques were grouped into a HP group (n = 25) and a control (CON) group (n = 25) according to blood pressure. An ALOKA LISENDO 880 Color Doppler Ultrasound with a L441 3-15 MHZ probe was used to obtain a longitudinal section scan to determine the regions of interests (ROIs) of the common carotid artery. VFM-based WSS measurements were obtained by selecting the ROI with optimal image quality from three full cardiac cycles. WSS-derived measurements, including WSSmax, WSSmin, and WSSmean, were analyzed and compared between the HP and CON groups. In addition, the correlations between WSS-derived measurements and the carotid artery intima-media thickness (IMT) were also analyzed. Results: There were significant statistical differences in WSSmax and WSSmean between patients in the HP and CON groups. Specifically, the HP group had significantly decreased WSSmax and WSSmean compared to the CON group (WSSmax: 1.781 ± 0.305 Pa vs. 2.286 ± 0.257 Pa; WSSmean: 1.276 ± 0.333 Pa vs. 1.599 ± 0.293 Pa, both p < 0.001). However, there was no statistical difference in WSSmin between the groups (0.79 ± 0.36 vs. 0.99 ± 0.42, p = 0.080). Additionally, Spearman's correlation analysis indicated that the WSS-derived parameters were negatively correlated with the IMT (p < 0.001). Conclusion: Vascular VFM technology shows promising results in the quantitative assessment of difference in hemodynamics of the vascular flow field between patients with HP and normal controls. Difference in WSS may serve as a potential predictor for the development of arteriosclerosis risks.

Using cooperative game model of air pollution governance to study the cost sharing in Yangtze River Delta region.

To solve the increasingly serious air pollution problem, regional air pollution collaborative governance as an effective way is introduced in this paper. Firstly, this study constructs a game model of regional air pollution collaborative governance, and three classic cost sharing methods are used to allocate the cost of air pollution governance; Then the emission reduction cost of regional cooperative governance is obtained; Finally, the study makes an empirical analysis on the cost sharing of SO2 emission reduction by four local governments of the Yangtze River Delta region in 2017. The results show that: (i) The emission reduction cost of regional cooperative governance is better than that of individual governance, and in 2017 the cost of SO2 cooperative governance in Yangtze River Delta region is reduced by about 1.8% compared with the individual governance; (ii) The Shapley value method is utilized to allocate the benefits of the cooperative SO2 governance of four provinces in the Yangtze River Delta region, which indicates that all local governments can obtain certain profits from this cooperation and the cooperative alliance is stable; (iii) Collaborative governance of regional air pollution can meet the requirements of both collective rationality and individual rationality at the same time.

Analysis of the impact of foreign direct investment on urbanization in China from the perspective of "circular economy".

Persisting in opening up and achieving coordinated development of economy, society, and ecology is China's major strategies for achieving sustainable urbanization. Ecological efficiency is a reasonable indicator to measure the development level of a circular economy. Therefore, using the statistical data of 30 provinces in China from 2004 to 2016, this paper uses the super-efficiency SBM model that considers undesired output to measure the eco-efficiency value, which is used to measure the level of circular economy development in each province. Based on this, a panel model is constructed to test the impact of circular economy and FDI on urbanization. The empirical results show that (1) there is a complex nonlinear relationship between the development of circular economy and the advancement of urbanization, and the shape of the curve varies with areas; (2) FDI under environmental regulation is conducive to promoting China's urbanization to achieve green, effective, and sustainable development; and (3) the development of the tertiary industry, human resources, innovation capabilities, and employment situation is conducive to promoting China's urbanization. Finally, based on the empirical results, this paper puts forward policy recommendations to achieve green, efficient, and intelligent development of Chinese cities by promoting the development of a circular economy and strengthening FDI screening.

Assessment of ecological vulnerability of resource-based cities based on entropy-set pair analysis.

ABSTRACTResource-based cities rise in the process of industrialization in China. These cities provide important resources for economic development of the country. However, due to the long-term and high-intensity exploitation of resources, resource-based cities are generally facing serious environmental pollution and ecological damages, which seriously threaten the survival and development of them. In order to evaluate and monitor ecological vulnerability of resource-based cities effectively, and solve the problem of fuzziness and randomness in the evaluation process, a comprehensive evaluation model based on entropy-set pair analysis has been built. First, the evaluation index system of resource-based cities' ecological vulnerability is constructed from four aspects of resource, economy, society and ecological environment. Second, the paper gets weights by entropy and evaluates vulnerability using the set pair theory. Finally, the level of ecological vulnerability of the case city is confirmed according to the principle of maximum connection degree. The results show that the evaluation indexes of resource, economy, society and ecological environment fluctuated but improved eventually in the year 2010 to 2016. And during this period, the ecological vulnerability of the case city changed from IV level to II level with a fluctuating state.

How does environmental regulation affect haze pollution governance?-An empirical test based on Chinese provincial panel data.

Recently, haze pollution is the most serious air problem in China. In the process of haze pollution governance, environmental regulation not only has a direct impact on haze pollution but may also affects haze pollution indirectly through four transmission channels, which are coal consumption, foreign direct investment (FDI), industrial structure and technological innovation. The purpose of this paper is to clarify how environmental regulation affects haze pollution governance through both direct and indirect impacts. Based on the difference Generalized Method of Moments (GMM), this paper explores the direct and indirect impact of environmental regulation on haze pollution governance over the period 2006-2016. The results show that China's current environmental regulation had effectively inhibited the haze pollution and achieved the expected effects. For coal consumption, it significantly aggravated haze pollution, but the ER implemented or not. However, environmental regulation provided a force mechanism to promote transformation and upgrading of industrial structure, thus to reverse the impact direction of industrial structure on haze pollution and mitigated the haze pollution. Moreover, the results indicate that FDI in China turned out to have a "pollution halo" effect and reduced the degree of haze pollution, while technological innovation had the "compliance cost" effect and increased the degree of haze pollution. Additionally, we find that automobile exhaust emissions and economic development were also important reasons for the increase of haze. According to the results, some policy implications were provided for the future haze pollution governance.

An ultra-facile and label-free immunoassay strategy for detection of copper (II) utilizing chemiluminescence self-enhancement of Cu (II)-ethylenediaminetetraacetate chelate.

The establishment of facile, rapid, sensitive and cost-effective protocols for the detection of heavy metals is of great significance for human health and environmental monitoring. Hereby, an ultra-facile and label-free immunoassay strategy was designed for detecting heavy metal ion by using Cu (II) as the model analyte. Cu (II) reacted previously with ethylenediaminetetraacetate (EDTA) was captured by immobilized monoclonal antibody for Cu (II)-EDTA chelate. Then Cu (II) was detected based on the self-enhancing effect of Cu (II)-EDTA chelate to luminol-H2O2 chemiluminescence reaction. The CL intensity is linear relative with Cu (II) concentration in a very wide range of 1.0-1000ng/mL, with a detection limit of 0.33ng/mL (S/N=3). Since the specificity of this proposed strategy relied on both the specificity of monoclonal antibody and the specificity of luminol-H2O2 system, it could avoid interference from most common ions. The proposed method was used successfully to detect Cu (II) in traditional Chinese medicine and environmental water samples with acceptable recovery values of 82-113%. This proof-of-principle work demonstrated the feasibility of the label-free immunoassay for heavy metal ions, and opened a new avenue for rapid screening and field assay for drug safety, environmental monitoring and clinical diagnosis.

[Determination of Background Value and Potential Ecological Risk Assessment of Heavy Metals in Sediments of the Danjiangkou Reservoir].

The aim of this study was to explore the pollution level and potential ecological risk of heavy metals in sediments of the Danjiangkou Reservoir, and the study obtained the background value of heavy metals of the surface sediments using reference element and statistical methods. The results indicated that the background values of Cr, Ni, Cu, Zn, As, Cd, Hg and Pb were 41.18, 34, 32.13, 76.84, 10.46, 0.70, 0.07 and 27.11 mg·kg-1, respectively. In addition, the potential ecological risks of the eight heavy metals in sediments were assessed using the Hakanson ecological risk index method. The values of RI for these eight metals in surface sediments ranged from 29.49 to 214.11, with the mean value of 118.91, and the pollution level was low. Furthermore, the Cfi value was in the order of Cd> Hg> Zn> Cr> Pb> Ni> As=Cu with the mean value of 1.05-1.31, and the pollution level varied from low to intermediate. The Cfi values of Cd and Hg were higher than those of other heavy metals with the mean values of 1.31 and 1.24, respectively, which should be paid more attentions.