Publications by authors named "Shuhui Zhao"

20 Publications

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Noninvasive prediction of residual disease for advanced high-grade serous ovarian carcinoma by MRI-based radiomic-clinical nomogram.

Eur Radiol 2021 Apr 16. Epub 2021 Apr 16.

Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, 215163, China.

Objectives: To develop a preoperative MRI-based radiomic-clinical nomogram for prediction of residual disease (RD) in patients with advanced high-grade serous ovarian carcinoma (HGSOC).

Methods: In total, 217 patients with advanced HGSOC were enrolled from January 2014 to June 2019 and randomly divided into a training set (n = 160) and a validation set (n = 57). Finally, 841 radiomic features were extracted from each tumor on T2-weighted imaging (T2WI) and contrast-enhanced T1-weighted imaging (CE-T1WI) sequence, respectively. We used two fusion methods, the maximal volume of interest (MV) and the maximal feature value (MF), to fuse the radiomic features of bilateral tumors, so that patients with bilateral tumors have the same kind of radiomic features as patients with unilateral tumors. The radiomic signatures were constructed by using mRMR method and LASSO classifier. Multivariable logistic regression analysis was used to develop a radiomic-clinical nomogram incorporating radiomic signature and conventional clinico-radiological features. The performance of the nomogram was evaluated on the validation set.

Results: In total, 342 tumors from 217 patients were analyzed in this study. The MF-based radiomic signature showed significantly better prediction performance than the MV-based radiomic signature (AUC = 0.744 vs. 0.650, p = 0.047). By incorporating clinico-radiological features and MF-based radiomic signature, radiomic-clinical nomogram showed favorable prediction ability with an AUC of 0.803 in the validation set, which was significantly higher than that of clinico-radiological signature and MF-based radiomic signature (AUC = 0.623, 0.744, respectively).

Conclusions: The proposed MRI-based radiomic-clinical nomogram provides a promising way to noninvasively predict the RD status.

Key Points: • MRI-based radiomic-clinical nomogram is feasible to noninvasively predict residual disease in patients with advanced HGSOC. • The radiomic signature based on MF showed significantly better prediction performance than that based on MV. • The radiomic-clinical nomogram showed a favorable prediction ability with an AUC of 0.803.
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http://dx.doi.org/10.1007/s00330-021-07902-0DOI Listing
April 2021

Screening and Identification of a Specific Binding Peptide to Ovarian Cancer Cells from a Phage-Displayed Peptide Library.

Int J Pept Res Ther 2021 Apr 3:1-9. Epub 2021 Apr 3.

Department of Obstetrics and Gynecology, Xijing Hospital, The Fourth Military Medical University, Xi'an, 710032 Shaanxi China.

To select specific binding peptides for imaging and detection of human ovarian cancer. The phage 12-mer peptide library was used to select specific phage clones to ovarian cancer cells. After four rounds of biopanning, the binding specificity of randomly selected phage clones to ovarian cancer cells was determined by enzyme-linked immunosorbent assay (ELISA). DNA sequencing and homology analysis were performed on specifically bound phages. The binding ability of the selected peptides to SKOV3 cells was confirmed by fluorescence microscopy and flow cytometry. After four rounds of optimized biological panning, phage recovery was 34-fold higher than that of the first round, and the specific phage clones bound to SKOV3 cells were significantly enriched. A total of 32 positive phage clones were preliminarily identified by ELISA from 54 randomly selected clones, and the positive rate was 59.3%. S36 was identified as the clone with best affinity to SKOV3 cells via fluorescence microscopy and flow cytometry. A representative clone of OSP2, S36 is expected to be an effective probe for diagnosis and treatment of ovarian cancer.
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http://dx.doi.org/10.1007/s10989-021-10206-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8019349PMC
April 2021

Growth differentiation factor-15 promotes immune escape of ovarian cancer via targeting CD44 in dendritic cells.

Exp Cell Res 2021 May 23;402(1):112522. Epub 2021 Mar 23.

Department of Obstetrics and Gynecology, Xijing Hospital, Fourth Military Medical University, No.127 Changle Road (West), Xi'an City, Shannxi Province, 710032, China. Electronic address:

Immune escape is the main cause of the low response rate to immunotherapy for cancer, including ovarian cancer. Growth differentiation factor-15 (GDF-15) inhibits immune cell function. However, only few reports described the mechanism. Therefore, the aim of this study was to investigate the mechanism of immune escape regulated by GDF-15 in ovarian cancer. Ovarian cancer patients and healthy women were enrolled in this study. Immunohistochemistry and ELISA were performed to measure GDF-15 expression. Immunoprecipitation combined with mass spectrometry, surface plasmon resonance, and co-immunoprecipitation assay were used to evaluate the interaction between GDF-15 and the surface molecules of DCs. Immunofluorescence analysis, flow cytometry and transwell assay were used to evaluate additional effects of GDF-15 on DCs. The results showed that GDF-15 expression was higher in the ovarian cancer patients compared to that in the healthy women. The TIMER algorithm revealed that highly GDF-15 expression is associated with immune DC infiltration in immunoreactive high-grade serous carcinoma. A further study showed that GDF-15 suppressed DCs maturation, as well as IL-12p40 and TNF-α secretion, the length and number of protrusions and the migration. More importantly, CD44 in the surface of DCs interacted with GDF-15. The overexpression of CD44 in DCs resulted in the suppression of the inhibitory effect of GDF-15 on the length and number of DC synapses. In DCs overexpressing CD44 the inhibition of GDF-15 on the expression of CD11c, CD83 and CD86 was decreased, while in DCs with a knockdown of CD44 the inhibition was further enhanced. Knockdown of CD44 in DCs enhanced the inhibitory effect of GDF-15 on DC migration, while the overexpression of CD44 inhibited the inhibitory effect of GDF-15 on DC migration. In conclusion, the present study suggested that GDF-15 might facilitate ovarian cancer immune escape by interacting with CD44 in DCs to inhibit their function.
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http://dx.doi.org/10.1016/j.yexcr.2021.112522DOI Listing
May 2021

Polymerase/Nicking Enzyme Powered Dual-Template Multi-Cycle G-Triplex Machine for HIV-1 Determination.

Anal Sci 2020 Dec 11. Epub 2020 Dec 11.

Key Laboratory of Clinical Laboratory Diagnostics (Ministry of Education of China), Department of Laboratory Medicine, Chongqing Medical University.

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http://dx.doi.org/10.2116/analsci.20P413DOI Listing
December 2020

MR image-based radiomics to differentiate type Ι and type ΙΙ epithelial ovarian cancers.

Eur Radiol 2021 Jan 2;31(1):403-410. Epub 2020 Aug 2.

Department of Radiology, Jinshan Hospital, Fudan University, 1508 Longhang Road, Jinshan District, Shanghai, 201508, China.

Objectives: Epithelial ovarian cancers (EOC) can be divided into type I and type II according to etiology and prognosis. Accurate subtype differentiation can substantially impact patient management. In this study, we aimed to construct an MR image-based radiomics model to differentiate between type I and type II EOC.

Methods: In this multicenter retrospective study, a total of 294 EOC patients from January 2010 to February 2019 were enrolled. Quantitative MR imaging features were extracted from the following axial sequences: T2WI FS, DWI, ADC, and CE-T1WI. A combined model was constructed based on the combination of these four MR sequences. The diagnostic performance was evaluated by ROC-AUC. In addition, an occlusion test was carried out to identify the most critical region for EOC differentiation.

Results: The combined radiomics model exhibited superior diagnostic capability over all four single-parametric radiomics models, both in internal and external validation cohorts (AUC of 0.806 and 0.847, respectively). The occlusion test revealed that the most critical region for differential diagnosis was the border zone between the solid and cystic components, or the less compact areas of solid component on direct visual inspection.

Conclusions: MR image-based radiomics modeling can differentiate between type I and type II EOC and identify the most critical region for differential diagnosis.

Key Points: • Combined radiomics models exhibited superior diagnostic capability over all four single-parametric radiomics models, both in internal and external validation cohorts (AUC of 0.834 and 0.847, respectively). • The occlusion test revealed that the most crucial region for differentiating type Ι and type ΙΙ EOC was the border zone between the solid and cystic components, or the less compact areas of solid component on direct visual inspection on T2WI FS. • The light-combined model (constructed by T2WI FS, DWI, and ADC sequences) can be used for patients who are not suitable for contrast agent use.
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http://dx.doi.org/10.1007/s00330-020-07091-2DOI Listing
January 2021

Effect of sea ice retreat on marine aerosol emissions in the Southern Ocean, Antarctica.

Sci Total Environ 2020 Nov 20;745:140773. Epub 2020 Jul 20.

Key Laboratory of Global Change and Marine Atmospheric Chemistry, Ministry of Natural Resources, Xiamen 361005, China; Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China.

Sea ice retreat in the polar region is expected to increase the emissions of sea salt aerosols and biogenic gases, which may significantly impact the climate by increasing cloud condensation nuclei (CCN) population and changing solar radiation. In this study, aerosol compositions were measured at high-time-resolution (1 h) with an in-situ gas and aerosol composition monitoring system in polynya regions of the Southern Ocean (SO) to access the effects of sea ice concentrations on the sea salt aerosol (SSA) and secondary biogenic aerosol (SBA) in the SO. SSA emissions increased by more than 30% as sea ice concentration decreased from 85% to 29%. However, SSA emissions did not increase monotonically as the sea ice concentration decreased. The highest SSA concentration occurred in drifting sea ice region. Sea ice melting increased SBA concentrations by enhancing the air-sea exchanges of SBA precursor gases and the release of algae from sea ice. Positive correlations between SSA and wind speed were present in different sea ice regions, while SBA didn't reveal an obvious correlation with wind speed in the SO. The impact of wind speed on the SSA emissions were very different, Higher slope value of 41.83 and 35.81 were present in the DSI and SIF region, while the value was only about 16.74 in the SIC region. The results extended the knowledge of the effect of future sea ice retreat on marine aerosol emissions and potential climate changes in the polar region.
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http://dx.doi.org/10.1016/j.scitotenv.2020.140773DOI Listing
November 2020

Pure dysgerminoma of the ovary: CT and MRI features with pathological correlation in 13 tumors.

J Ovarian Res 2020 Jun 17;13(1):71. Epub 2020 Jun 17.

Department of Radiology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, 1665 Kongjiang Road, Shanghai, 200092, China.

Background: To investigate the spectrum of CT and MRI findings of dysgerminoma of the ovary.

Methods: CT and MRI imaging of 12 patients with 13 histologically proven dysgerminomas of the ovary were retrospectively reviewed. Patients ages ranged from 6 ~ 27 years (mean, 17.2 years). Two observers evaluated the following CT and MRI features of the tumor by consensus: (i) location, shape, and size; (ii) attenuation, T2 signal intensity, and ADC value; (iii) patterns of contrast enhancement; (iv) presence of fibrovascular septa; (v) presence of necrosis, hemorrhage, and calcification; (vi) presence of "ovarian vascular pedicle" sign. We also noted the extent or stage of the tumors.

Results: 75% lesions arised in the right ovary. Bilateral ovaries were involved in one case. Tumors displayed as a purely or predominantly solid mass (mean size, 17.0 ± 7.8 cm). Ten tumors were shaped multilobulated. The mean ADC value of lesions was 0.830 ± 0.154 × 10 mm/s. Characteristic fibrovascular septa were observed in all lesions. Among them, classic septa were present in 69% lesions. They were thin, hypointense on T2WI with a linear intense enhancement indicating the blood vessels in septa. Due to the stromal edema, fibrovascular septa may become thick even amorphous in shape, hyperintense on T2WI and even low attenuation on CT with a slight enhancement except for a bright blood vessel on the edge. Massive necrosis was observed only in one lesion. Calcification was present in 3 of the 5 tumors on CT. "Ovarian vascular pedicle" sign was present in 12 lesions. Lymphadenopathy, retroperitoneal spread, and distant metastases combined with an implantation in Douglas' cul-de-sac were present in one patient respectively.

Conclusion: On CT and MR images, ovarian dysgerminoma often appears as a large solid mass. The edematous condition of characteristic fibrovascular septa can be well displayed by imaging which then can guide the radiologists to make an accurate diagnosis. Calcifications often occur in the tumor. Nonspecific low ADC value and "ovarian vascular pedicle" sign may narrow the differential diagnosis.
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http://dx.doi.org/10.1186/s13048-020-00674-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7301981PMC
June 2020

MRI-Based Machine Learning for Differentiating Borderline From Malignant Epithelial Ovarian Tumors: A Multicenter Study.

J Magn Reson Imaging 2020 09 11;52(3):897-904. Epub 2020 Feb 11.

Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China.

Background: Preoperative differentiation of borderline from malignant epithelial ovarian tumors (BEOT from MEOT) can impact surgical management. MRI has improved this assessment but subjective interpretation by radiologists may lead to inconsistent results.

Purpose: To develop and validate an objective MRI-based machine-learning (ML) assessment model for differentiating BEOT from MEOT, and compare the performance against radiologists' interpretation.

Study Type: Retrospective study of eight clinical centers.

Population: In all, 501 women with histopathologically-confirmed BEOT (n = 165) or MEOT (n = 336) from 2010 to 2018 were enrolled. Three cohorts were constructed: a training cohort (n = 250), an internal validation cohort (n = 92), and an external validation cohort (n = 159).

Field Strength/sequence: Preoperative MRI within 2 weeks of surgery. Single- and multiparameter (MP) machine-learning assessment models were built utilizing the following four MRI sequences: T -weighted imaging (T WI), fat saturation (FS), diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC), and contrast-enhanced (CE)-T WI.

Assessment: Diagnostic performance of the models was assessed for both whole tumor (WT) and solid tumor (ST) components. Assessment of the performance of the model in discriminating BEOT vs. early-stage MEOT was made. Six radiologists of varying experience also interpreted the MR images.

Statistical Tests: Mann-Whitney U-test: significance of the clinical characteristics; chi-square test: difference of label; DeLong test: difference of receiver operating characteristic (ROC).

Results: The MP-ST model performed better than the MP-WT model for both the internal validation cohort (area under the curve [AUC] = 0.932 vs. 0.917) and external validation cohort (AUC = 0.902 vs. 0.767). The model showed capability in discriminating BEOT vs. early-stage MEOT, with AUCs of 0.909 and 0.920, respectively. Radiologist performance was considerably poorer than both the internal (mean AUC = 0.792; range, 0.679-0.924) and external (mean AUC = 0.797; range, 0.744-0.867) validation cohorts.

Data Conclusion: Performance of the MRI-based ML model was robust and superior to subjective assessment of radiologists. If our approach can be implemented in clinical practice, improved preoperative prediction could potentially lead to preserved ovarian function and fertility for some women.

Level Of Evidence: Level 4.

Technical Efficacy: Stage 2. J. Magn. Reson. Imaging 2020;52:897-904.
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http://dx.doi.org/10.1002/jmri.27084DOI Listing
September 2020

Molecular imaging-monitored radiofrequency hyperthermia-enhanced intratumoral herpes simplex virus-thymidine kinase gene therapy for rat orthotopic ovarian cancer.

Int J Hyperthermia 2020 ;37(1):101-109

Image-Guided Bio-Molecular Intervention Research and Division of Vascular and Interventional Radiology, Department of Radiology, University of Washington School of Medicine, Seattle, WA, USA.

To establish the technique of intratumoral combination therapy of radiofrequency hyperthermia (RFH) with herpes simplex virus-thymidine kinase/ganciclovir (HSV-TK/GCV) gene therapy for rat ovarian cancers. This study consisted of three parts: (1) experiments to establish the 'proof of principal' that combination of RFH and HSV-TK gene therapy has the synergistic effect on human ovarian cancer cells; (2) creation of bioluminescence imaging-detectable rat ovarian cancer model; and (3) experiments using this rat model to validate the technical feasibility of the combination therapy. Cells and nude rats were divided into four groups: (i) combination therapy (HSV-TK/GCV + RFH); (ii) RFH; (iii) HSV-TK/GCV; and (iv) phosphate-buffered saline (PBS). Data were analyzed using Dunnett -test or Kruskal-Wallis test. Cell proliferation assay demonstrated significantly greater reduction in viable cells with the combination therapy [0.52 (0.43, 0.61)] compared to other treatments [RFH 0.90 (0.84, 0.96), HSV-TK/GCV 0.71 (0.53, 0.88), PBS 1 (1, 1);  < .05]. For 24 rat models with bioluminescence imaging-detectable orthotopic ovarian cancer ( = 6 per group), optical imaging demonstrated significantly decreased relative bioluminescence signal with the combination therapy [0.81 (0.52, 1.08)] compared to other treatments [RFH 3.60 (2.34, 4.86), HSV-TK/GCV 2.21 (1.71, 2.71), PBS 3.74 (3.19, 4.29);  < .001]. Ultrasound imaging demonstrated the smallest relative tumor volume with the combination therapy [0.78 (0.45, 1.11) versus 3.50 (2.67, 4.33), 2.10 (0.83, 3.37), 3.70 (1.79, 5.61);  < .05]. The feasibility of intratumoral RFH-enhanced HSV-TK/GCV gene therapy was established on a unique rat model with molecular imaging-detectable orthotopic ovarian cancer.
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http://dx.doi.org/10.1080/02656736.2020.1711973DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7034662PMC
October 2020

Significant Underestimation of Gaseous Methanesulfonic Acid (MSA) over Southern Ocean.

Environ Sci Technol 2019 Nov 8;53(22):13064-13070. Epub 2019 Nov 8.

Key Laboratory of Global Change and Marine-Atmospheric Chemistry , MNR , Xiamen 361005 , China.

Methanesulfonic acid (MSA), derived from the oxidation of dimethylsulfide (DMS), has a significant impact on biogenic sulfur cycle and climate. Gaseous MSA (MSA) has been often ignored in previous studies due to its quick conversion to particulate MSA (MSA) and low concentrations. MSA, MSA, and nss-SO were observed simultaneously for the first time with high-time-resolution (1 h) in the Southern Ocean (SO). The mean MSA level reached up to 3.3 ± 1.6 pptv, ranging from ∼24.5 pptv in the SO, contributing to 31% ± 3% to the total MSA (MSA). A reduction of the MSA to nss-SO ratios by about 30% was obtained when MSA was not accounted for in the calculation, indicating that MSA was very important in the assessment of the biogenic sulfur contributions in the atmosphere. Mass ratios of MSA to nss-SO increased first and then decreased with the temperature from -10 to 5 °C, with a maximum value at the temperature of -3 °C. Positive correlations between MSA to MSA ratios and temperature were presented, when the temperature was higher than 5 °C. This study highlights the importance of MSA for understanding the atmospheric DMS oxidation mechanism and extends the knowledge of MSA formation in the marine atmosphere.
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http://dx.doi.org/10.1021/acs.est.9b05362DOI Listing
November 2019

Combining Clinical Characteristics and Specific Magnetic Resonance Imaging Features to Predict Placenta Accreta.

J Comput Assist Tomogr 2019 Sep/Oct;43(5):775-779

From the Department of Radiology, Xinhua Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Chongming Branch, Shanghai, China.

Objective: The aim of this study was to explore the independent clinical and magnetic resonance imaging (MRI) performance risk factors for predicting placenta accreta.

Methods: From January 2012 to December 2015, we retrospectively reviewed the clinical characteristics and MRI features of 97 patients. Of these, 42 were confirmed to be placenta accreta by pathological results or cesarean delivery findings. We tried to identify the independent risk factors by multivariate logistic regression model for significant differences in variables determined by univariate analysis.

Results: The multivariate logistic regression model indicated that 2 or more instances of previous cesarean deliveries and/or abortions, placenta previa, and placenta-myometrial interface interruption were independent risk factors for placenta accreta. The odd ratios were 3.79 for patients who had 2 or more instances of previous cesarean deliveries and/or abortions, 0.04 for marginal/partial placenta previa, 0.024 for complete placenta previa, and 6.56 for placenta-myometrial interface interruption. The values of accuracy and positive prediction by combination of a single clinical risk factor and placenta-myometrial interface interruption and of positive prediction by a combination of all 3 risk factors for predicting placenta accreta were raised to 83.5%, 75%, and 92.9%, respectively. We obtained 3 different risk groups by different combinations of all 3 risk factors.

Conclusions: The study suggested that 2 or more instances of previous cesarean deliveries and/or abortion, placenta previa, and placenta-myometrial interface interruption were independent risk factors for placenta accreta. A combination of a single clinical risk factor and an MRI risk factor can improve the diagnosis of placenta accreta, and a combination of all 3 risk factors could help recognize patients with placenta accreta.
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http://dx.doi.org/10.1097/RCT.0000000000000894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6752690PMC
October 2019

Effect of air masses motion on the rapid change of aerosols in marine atmosphere.

J Environ Sci (China) 2019 Sep 13;83:217-228. Epub 2019 Apr 13.

Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China; Key Laboratory of Global Change and Marine-Atmospheric Chemistry, Xiamen 361005, China.

The impact of air masses motion on marine aerosol properties was investigated using an on-board single particle mass spectrometer (SPAMS) deployed for the determination of single particle size resolved chemical composition over Southeast China Sea. Two aerosol blooms (E1 and E2) were observed during the cruise. High average particle number count occurred in E1 (7320), followed by E2 (5850), which was more than 100-150 times of the average particle number count during normal periods. Particles were classified as four major sources, including continental source, shipping source, marine source, and transport source based on the mass spectral similarity. Transport source was identified as those particles with high particle number count occurred only during aerosol bloom period. Three sub-types of EC-Ca, OC-Ca, and Al-rich were classified as transport source. EC-Ca was the dominant particles of the transport source, accounting for more than 70% of the total particles in aerosol bloom events. A uni-modal size distribution in the size range of 0.1-2.0 μm was observed during normal period, while a bimodal distribution with a tiny mode (<0.3 μm) and a coarse mode between 0.4 and 0.6 μm was present during aerosol bloom. The variation of aerosol source is consistent with air masses back trajectories, for the reason that most of the long-range air trajectories are from the ocean, while short air trajectories originate in the continental regions, which means that air masses have a significant impact on the aerosol physical-chemical properties along their tracks.
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http://dx.doi.org/10.1016/j.jes.2019.04.005DOI Listing
September 2019

Impact of marine and continental sources on aerosol characteristics using an on-board SPAMS over southeast sea, China.

Environ Sci Pollut Res Int 2018 Oct 3;25(30):30659-30670. Epub 2018 Sep 3.

Institute of Atmospheric Environment Safety and pollution Control, Jinan University, Guangzhou, 511443, China.

The chemical composition of atmospheric aerosols was characterized using an on-board single particle aerosol mass spectrometer (SPAMS) over the Southeast China Sea. High-time-resolution observation of marine aerosols was carried out to clarify the source of aerosols and the interaction of marine and continental aerosols. Atmospheric aerosols were determined by the interaction of continental and marine sources over coastal area. Aerosols from continental sources flux into sea surfaces through deposition or diffusion, which results in the rapid decrease of continental aerosols. Five main subtypes of carbonaceous particles are identified as C_Al-Si, C_V-Ni, C_S, C_K, and C_secondary to clarify the impact of marine and continental sources on atmospheric aerosols. High fraction of C_Al-Si and C_secondary is present over XA (Xiamen anchorage), accounting for 23.8% and 18.6% of total carbonaceous particles. Contrarily, the relative percentage of C_S increases as the distance from land to sea increases. The influence of continental aerosols declines, while the contribution of marine aerosols increases as the distance from land to sea increases. Air masses in XA, LSA (land to sea area), SLA (sea to land area), and SA (sea area) were all from ocean during the observation period, resulting in low relative fraction of continental aerosols in SLA, SA, and LSA. High-time-resolution measurement is useful to understand aerosol source types and the impact of marine and continental sources on marine atmosphere aerosols.
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http://dx.doi.org/10.1007/s11356-018-2902-5DOI Listing
October 2018

Pollutants identification of ambient aerosols by two types of aerosol mass spectrometers over southeast coastal area, China.

J Environ Sci (China) 2018 Feb 1;64:252-263. Epub 2017 Jul 1.

Institute of Atmospheric Environment Safety and Pollution Control, Jinan University, Guangzhou 510632, China.

Two different aerosol mass spectrometers, Aerodyne Aerosol Mass Spectrometer (AMS) and Single Particle Aerosol Mass Spectrometer (SPAMS) were deployed to identify the aerosol pollutants over Xiamen, representing the coastal urban area. Five obvious processes were classified during the whole observation period. Organics and sulfate were the dominant components in ambient aerosols over Xiamen. Most of the particles were in the size range of 0.2-1.0μm, accounting for over 97% of the total particles measured by both instruments. Organics, as well as sulfate, measured by AMS were in good correlation with measured by SPAMS. However, high concentration of NH was obtained by AMS, while extremely low value of NH was detected by SPAMS. Contrarily, high particle number counts of NO and Cl were given by SPAMS while low concentrations of NO and Cl were measured by AMS. The variations of POA and SOA obtained from SPAMS during event 1 and event 2 were in accordance with the analysis of HOA and OOA given by AMS, suggesting that both of AMS and SPAMS can well identify the organic clusters of aerosol particles. Overestimate or underestimate of the aerosol sources and acidity would be present in some circumstances when the measurement results were used to analyze the aerosol properties, because of the detection loss of some species for both instruments.
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http://dx.doi.org/10.1016/j.jes.2017.06.030DOI Listing
February 2018

Characterization of lead-containing aerosol particles in Xiamen during and after Spring Festival by single-particle aerosol mass spectrometry.

Sci Total Environ 2017 Feb 19;580:1257-1267. Epub 2016 Dec 19.

Key Lab of Global Change and Marine-Atmospheric Chemistry of State Oceanic Administration, Third Institute of Oceanography, State Oceanic Administration, Fujian, Xiamen 361005, China.

To comparatively analyze lead (Pb)-containing particles during and after the Chinese Spring Festival (SF), real-time single-particle aerosol mass spectrometry (SPAMS) was conducted in Xiamen during February 9-19 and March 4-14, 2013. Pb-containing particles were found in 2.4% and 5.3% of the total particle numbers during and after SF, respectively. Based on the SPAMS mass spectral results, the Pb-containing particles were classified into three major types and 11 subtypes: Pb-rich particles comprising Pb-nitrate, Pb-sulfate and Pb-chloride; K-rich particles comprising K-nitrate, K-sulfate, K-metal, K-carbonaceous, K-phosphate, and K-chloride; and metal particles including Fe-rich and Mn-nitrate particles. During SF, lower contributions of Pb-containing particles were due to the effect of the SF holiday. Firework emissions contributed little to the Pb-containing particles. K-rich particles were a major contribution to Pb-containing particles during SF, accounting for approximately 70% of the total number of Pb-containing particles. After SF, significantly increased Pb-containing particles were observed, coincided with NO and SO, due to increased industrial activities and other anthropogenic activities, and Pb-rich particles increased to approximately 50.3% of the total number of Pb-containing particles. Local industrial emissions and the stagnant meteorological conditions resulted in the higher concentrations of Pb-containing particles in the early morning after SF, especially Pb-nitrate particles. This study provides data on the in-situ monitoring of Pb emissions during and after SF and could be helpful for the mitigation of Pb pollution.
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http://dx.doi.org/10.1016/j.scitotenv.2016.12.086DOI Listing
February 2017

Magnetic Resonance Spectroscopy for Evaluating Portal-Systemic Encephalopathy in Patients with Chronic Hepatic Schistosomiasis Japonicum.

PLoS Negl Trop Dis 2016 12 15;10(12):e0005232. Epub 2016 Dec 15.

Department of Radiology, Jinshan Hospital & Shanghai Medical College, Fudan University, Shanghai, China.

Portal-systemic encephalopathy (PSE) is classified as type B hepatic encephalopathy. Portal-systemic shunting rather than liver dysfunction is the main cause of PSE in chronic hepatic schistosomiasis japonicum (HSJ) patients. Owing to lack of detectable evidence of intrinsic liver disease, chronic HSJ patients with PSE are frequently clinically undetected or misdiagnosed, especially chronic HSJ patients with covert PSE (subclinical encephalopathy). In this study, we investigated whether magnetic resonance spectroscopy (MRS) could be a useful tool for diagnosing PSE in chronic HSJ patients. Magnetic resonance (MR) T1-weighted imaging, diffusion-weighted imaging, and MRS were performed in 41 chronic HSJ patients with suspected PSE and in 21 age-matched controls. The T1 signal intensity index (T1SI) and apparent diffusion coefficient (ADC) value were obtained in the Globus pallidus. Liver function was also investigated via serum ammonia and liver function tests. Higher T1SI and ADC values, increased lactate and glutamine levels, and decreased myo-inositol were found in the bilateral Globus pallidus in chronic HSJ patients with PSE. No significantly abnormal serum ammonia or liver function tests were observed in chronic HSJ patients with PSE. On the basis of these findings, we propose a diagnostic procedure for PSE in chronic HSJ patients. This study reveals that MRS can be useful for diagnosing PSE in chronic HSJ patients.
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http://dx.doi.org/10.1371/journal.pntd.0005232DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5199111PMC
December 2016

Effect of typhoon on atmospheric aerosol particle pollutants accumulation over Xiamen, China.

Chemosphere 2016 Sep 10;159:244-255. Epub 2016 Jun 10.

Key Laboratory of Global Change and Marine-Atmospheric Chemistry, Third Institute of Oceanography, SOA, Xiamen 361005, PR China.

Great influence of typhoon on air quality has been confirmed, however, rare data especially high time resolved aerosol particle data could be used to establish the behavior of typhoon on air pollution. A single particle aerosol spectrometer (SPAMS) was employed to characterize the particles with particle number count in high time resolution for two typhoons of Soulik (2013) and Soudelor (2015) with similar tracks. Three periods with five events were classified during the whole observation time, including pre - typhoon (event 1 and event 2), typhoon (event 3 and event 4) and post - typhoon (event 5) based on the meteorological parameters and particle pollutant properties. First pollutant group appeared during pre-typhoon (event 2) with high relative contributions of V - Ni rich particles. Pollution from the ship emissions and accumulated by local processes with stagnant meteorological atmosphere dominated the formation of the pollutant group before typhoon. The second pollutant group was present during typhoon (event 3), while typhoon began to change the local wind direction and increase wind speed. Particle number count reached up to the maximum value. High relative contributions of V - Ni rich and dust particles with low value of NO3(-)/SO4(2-) was observed during this period, indicating that the pollutant group was governed by the combined effect of local pollutant emissions and long-term transports. The analysis of this study sheds a deep insight into understand the relationship between the air pollution and typhoon.
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http://dx.doi.org/10.1016/j.chemosphere.2016.06.006DOI Listing
September 2016

Are emissions of black carbon from gasoline vehicles overestimated? Real-time, in situ measurement of black carbon emission factors.

Sci Total Environ 2016 Mar 21;547:422-428. Epub 2016 Jan 21.

Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary T2N 1N4, Canada. Electronic address:

Accurately quantifying black carbon (BC) emission factors (EFs) is a prerequisite for estimation of BC emission inventory. BC EFs determined by measuring BC at the roadside or chasing a vehicle on-road may introduce large uncertainty for low emission vehicles. In this study, BC concentrations were measured inside the tailpipe of gasoline vehicles with different engine sizes under different driving modes to determine the respective EFs. BC EFs ranged from 0.005-7.14 mg/kg-fuel under the speeds of 20-70 km/h, 0.05-28.95 mg/kg-fuel under the accelerations of 0.5-1.5m/s(2). Although the water vapor in the sampling stream could result in an average of 12% negative bias, the BC EFs are significantly lower than the published results obtained with roadside or chasing vehicle measurement. It is suggested to conduct measurement at the tailpipe of gasoline vehicles instead of in the atmosphere behind the vehicles to reduce the uncertainty from fluctuation in ambient BC concentration.
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http://dx.doi.org/10.1016/j.scitotenv.2015.12.115DOI Listing
March 2016

Investigation on the inclusion interaction of 4-sulfonatocalix[n]arenes with 1-(4-nitrophenyl)piperazine.

Spectrochim Acta A Mol Biomol Spectrosc 2014 Nov 9;132:44-51. Epub 2014 May 9.

Institute of Applied Chemistry, Shanxi University, Taiyuan 030006, China.

The inclusion behaviors of 4-Sulfonatocalix[n]arenes (SCXn) (n=4, 6, 8) with 1-(4-nitrophenyl)piperazine (NPP) were investigated by UV spectroscopy and fluorescence spectroscopy at different pH values (pH=3.05, 6.50, 8.40). The UV absorption and fluorescence intensity of NPP remarkably increased in presence of SCXn revealing formation of the inclusion complexes between NPP and SCXn. Moreover, the formation constants (K) of inclusion complexes were also determined by the non-linear fitting method, and the obtained data showed that the formation constants decreasedgradually with the increasing of the pH value. When the pH value was 3.05, the formation constant of NPP with SCX8 reached a maximum of 1.7×10(7) L mol(-1). The stoichiometric ratio was verified to be 1:1 by the continuous variation method. Meanwhile FT-IR and DSC analysis also indicated that NPP could form the inclusion complex with SCXn. In order to explore the inclusion mechanism of NPP with SCXn, 1H NMR and molecular modeling studies were carried out and experimental results showed that the part of benzene ring of NPP penetrated into the hydrophobic cavity of SCXn.
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http://dx.doi.org/10.1016/j.saa.2014.04.156DOI Listing
November 2014

Ion chemistry and individual particle analysis of atmospheric aerosols over Mt. Bogda of eastern Tianshan Mountains, Central Asia.

Environ Monit Assess 2011 Sep 25;180(1-4):409-26. Epub 2010 Nov 25.

State Key Laboratory of Cryospheric Sciences/Tianshan Glaciological Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China.

Aerosol samples were collected during the scientific expedition to Mt. Bogda in July-August, 2009. The major inorganic ions (Na( + ), NH⁺₄, K( + ), Mg(2 + ), Ca(2 + ), Cl( - ), SO²⁻₄, and NO⁻₃) of the aerosols were determined by ion chromatography. SO²⁻₄, NO⁻₃, and Ca(2 + ) were the dominate ions, with the mean concentrations of 0.86, 0.56, and 0.28 μg m⁻³, respectively. These mean ion concentrations were generally comparable with the background conditions in remote site of Xinjiang, while much lower than those in Ürümqi. Morphology and elemental compositions of 1,500 particles were determined by field emission scanning electron microscopy equipped with an energy dispersive X-ray spectrometer. Based on the morphology and elemental compositions, particles were classed into four major groups: soot (15.1%), fly ash (4.7%), mineral particles (78.9%), and little other matters (0.8% Fe-rich particles and 0.5% unrecognized particles). Presence of soot and fly ash particles indicated the influence of anthropogenic pollutions, while abundance mineral particles suggested that natural processes were the primary source of aerosols over this region, coinciding with the ionic analysis. Backward air mass trajectory analysis suggested that Ürümqi may contribute some anthropogenic pollution to this region, while the arid and semi-arid regions of Central Asia were the primary source.
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http://dx.doi.org/10.1007/s10661-010-1796-6DOI Listing
September 2011