Publications by authors named "Lidan Zhu"

26 Publications

  • Page 1 of 1

Surface-enhanced Raman scattering for mixing state characterization of individual fine particles during a haze episode in Beijing, China.

J Environ Sci (China) 2021 Jun 22;104:216-224. Epub 2020 Dec 22.

MOE Key Laboratory of Resources and Environmental System Optimization, College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China; Guangdong Provincial Key Laboratory of Petrochemcial Pollution Processes and Control, School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming 525000, China.

The nondestructive characterization of the mixing state of individual fine particles using the traditional single particle analysis technique remains a challenge. In this study, fine particles were collected during haze events under different pollution levels from September 5 to 11 2017 in Beijing, China. A nondestructive surface-enhanced Raman scattering (SERS) technique was employed to investigate the morphology, chemical composition, and mixing state of the multiple components in the individual fine particles. Optical image and SERS spectral analysis results show that soot existing in the form of opaque material was predominant during clear periods (PM ≤ 75 µg/m). During polluted periods (PM > 75 µg/m), opaque particles mixed with transparent particles (nitrates and sulfates) were generally observed. Direct classical least squares analysis further identified the relative abundances of the three major components of the single particles: soot (69.18%), nitrates (28.71%), and sulfates (2.11%). A negative correlation was observed between the abundance of soot and the mass concentration of PM. Furthermore, mapping analysis revealed that on hazy days, PM existed as a core-shell structure with soot surrounded by nitrates and sulfates. This mixing state analysis method for individual PM particles provides information regarding chemical composition and haze formation mechanisms, and has the potential to facilitate the formulation of haze prevention and control policies.
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http://dx.doi.org/10.1016/j.jes.2020.12.008DOI Listing
June 2021

Stronger secondary pollution processes despite decrease in gaseous precursors: A comparative analysis of summer 2020 and 2019 in Beijing.

Environ Pollut 2021 Jun 10;279:116923. Epub 2021 Mar 10.

State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing Key Laboratory of Indoor Air Quality Evaluation and Control, Tsinghua University, Beijing, 100084, China.

To control the spread of COVID-19, China implemented a series of lockdowns, limiting various offline interactions. This provided an opportunity to study the response of air quality to emissions control. By comparing the characteristics of pollution in the summers of 2019 and 2020, we found a significant decrease in gaseous pollutants in 2020. However, particle pollution in the summer of 2020 was more severe; PM levels increased from 35.8 to 44.7 μg m, and PM increased from 51.4 to 69.0 μg m from 2019 to 2020. The higher PM was caused by two sandstorm events on May 11 and June 3, 2020, while the higher PM was the result of enhanced secondary formation processes indicated by the higher sulfate oxidation rate (SOR) and nitrate oxidation rate (NOR) in 2020. Higher SOR and NOR were attributed mainly to higher relative humidity and stronger oxidizing capacity. Analysis of PM distribution showed that severe haze occurred when particles within Bin2 (size ranging 1-2.5 μm) dominated. SO and SO remained stable under different periods at 0.5 and 0.8, respectively, indicating that SO existed mainly in smaller particles. Decreases in NO and increases in NO from clean to polluted conditions, similar to the variations in PM distribution, suggest that NO played a role in the worsening of pollution. O concentrations were higher in 2020 (108.6 μg m) than in 2019 (96.8 μg m). Marked decreases in fresh NO alleviated the titration of O. Furthermore, the oxidation reaction of NO that produces NO was dominant over the photochemical reaction of NO that produces O, making NO less important for O pollution. In comparison, a lower VOC/NO ratio (less than 10) meant that Beijing is a VOC-limited area; this indicates that in order to alleviate O pollution in Beijing, emissions of VOCs should be controlled.
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http://dx.doi.org/10.1016/j.envpol.2021.116923DOI Listing
June 2021

Plasmacytoid Dendritic Cell Infiltration in Acute Myeloid Leukemia.

Cancer Manag Res 2020 6;12:11411-11419. Epub 2020 Nov 6.

Medical Center of Hematology, Xinqiao Hospital, Army Medical University, Chongqing 400037, People's Republic of China.

Introduction: Increasing evidence has demonstrated that plasmacytoid dendritic cells (PDCs) in the tumor microenvironment (TME) play an important role in tumorigenesis and progression. PDC infiltration has been found in certain malignancies such as classic Hodgkin's lymphoma and chronic myelomonocytic leukemia. Our previous work reported that PDC infiltration could occur in acute myeloid leukemia (AML), but the clinical significance of PDC in AML has not been thoroughly investigated.

Patients And Methods: Here, we evaluated the clinical significance of PDC to AML transition in a leukemia microenvironment. The frequency of PDCs in 80 acute myelomonocytic leukemia (AML-M4) and 83 acute monocytic leukemia (AML-M5) patients was determined by flow cytometry.

Results: We found 62 cases with PDC infiltration. These patients showed higher numbers of bone marrow blasts, higher mean Hb concentration, and required more cycles of chemotherapy before achieving complete remission (CR), but had lower white blood cell and platelet counts compared to patients without PDC infiltration. Drug sensitivity analysis showed that patients with PDC infiltration had lower sensitivity to standard chemotherapy regimens. Kaplan-Meier survival curves demonstrated that patients with PDC infiltration had a shorter overall survival (OS) time and progression-free survival time.

Discussion: These results suggested that PDC infiltration can be used for risk stratification of AML-M4/M5, and PDCs may transdifferentiate into leukemia in an AML microenvironment.
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http://dx.doi.org/10.2147/CMAR.S260825DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7654521PMC
November 2020

Aqueous degradation of artificial sweeteners saccharin and neotame by metal organic framework material.

Sci Total Environ 2021 Mar 22;761:143181. Epub 2020 Oct 22.

Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.

The artificial sweeteners (ASs) saccharin (SAC) and neotame (NEO) are widely used across the globe and are considered as emerging contaminants in surface, ground, and drinking waters. To degrade SAC and NEO, the metal organic framework material Co-based bio-MOF-11 was prepared by hydrothermal reaction and used with peroxymonosulfate (PMS) activator. The effects of the initial concentration of SAC and NEO, bio-MOF-11-Co dosage, PMS concentration, initial pH, temperature, and competitive anions were determined. The results revealed that bio-MOF-11-Co effectively catalyzed the degradation of SAC and NEO and possessed good stability and recycling efficiency. The degradation reaction was effective from pH 3.6-9.8 and followed quasi-first-order kinetics with degradation rate constants of 0.001-0.013 min for SAC and 0.03-0.52 min for NEO. Increased temperature was conducive to the degradation of both artificial sweeteners. The presence of Cl inhibited the degradation of SAC and NEO, while the presence of CO promoted their degradation. Electron paramagnetic resonance (EPR) and free radical quenching demonstrated that the primary free radicals were sulfate radicals ( [Formula: see text] ) and hydroxyl radicals (HO). The change of cobalt oxidation state and electron transfer in bio-MOF-11-Co mainly induces the production of [Formula: see text] . A plausible mechanism for degradation is [Formula: see text] and HO attack on CS bonds, NS bonds, and benzene rings.
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http://dx.doi.org/10.1016/j.scitotenv.2020.143181DOI Listing
March 2021

Effect of rhG-CSF Combined With Decitabine Prophylaxis on Relapse of Patients With High-Risk MRD-Negative AML After HSCT: An Open-Label, Multicenter, Randomized Controlled Trial.

J Clin Oncol 2020 12 27;38(36):4249-4259. Epub 2020 Oct 27.

Medical Center of Hematology, Xinqiao Hospital, Army Medical University, Chongqing, China.

Purpose: Relapse is a major cause of treatment failure after allogeneic hematopoietic stem-cell transplantation (allo-HSCT) for high-risk acute myeloid leukemia (HR-AML). The aim of this study was to explore the effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) combined with minimal-dose decitabine (Dec) on the prevention of HR-AML relapse after allo-HSCT.

Patients And Methods: We conducted a phase II, open-label, multicenter, randomized controlled trial. Two hundred four patients with HR-AML who had received allo-HSCT 60-100 days before randomization and who were minimal residual disease negative were randomly assigned 1:1 to either rhG-CSF combined with minimal-dose Dec (G-Dec group: 100 µg/m of rhG-CSF on days 0-5 and 5 mg/m of Dec on days 1-5) or no intervention (non-G-Dec group). The primary outcome was relapse after transplantation, and the secondary outcomes were chronic graft-versus-host disease (cGVHD), safety of the treatment, and survival.

Results: The estimated 2-year cumulative incidence of relapse in the G-Dec group was 15.0% (95% CI, 8.0% to 22.1%), compared with 38.3% (95% CI, 28.8% to 47.9%) in the non-G-Dec group ( < .01), with a hazard ratio (HR) of 0.32 (95% CI, 0.18 to 0.57; < .01). There was no statistically significant difference between the G-Dec and non-G-Dec groups in the 2-year cumulative incidence of cGVHD without relapse (23.0% [95% CI, 14.7% to 31.3%] and 21.7% [95% CI, 13.6% to 29.7%], respectively; = .82), with an HR of 1.07 (95% CI, 0.60 to 1.92; = .81). After rhG-CSF combined with minimal-dose Dec maintenance, increasing numbers of natural killer, CD8+ T, and regulatory T cells were observed.

Conclusion: Our findings suggest that rhG-CSF combined with minimal-dose Dec maintenance after allo-HSCT can reduce the incidence of relapse, accompanied by changes in the number of lymphocyte subtypes.
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http://dx.doi.org/10.1200/JCO.19.03277DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7768335PMC
December 2020

Characteristics and seasonal variations of high-molecular-weight oligomers in urban haze aerosols.

Sci Total Environ 2020 Dec 23;746:141209. Epub 2020 Jul 23.

State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing Key Laboratory of Indoor Air Quality Evaluation and Control, Tsinghua University, Beijing 100084, China. Electronic address:

Organic aerosols (OA) undergo sophisticated physiochemical processes in the atmosphere, playing a crucial role in extreme haze formations over the Northern China Plain. However, current understandings of the detailed composition and formation pathways are limited. In this study, high-molecular weight (HMW) species were observed in samples collected year-round in urban Beijing, especially in autumn and winter, during 2016-2017. The positive-ion-mode mass spectra of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) showed that higher signal intensities were obtained in the mass-to-charge (m/z) ranges of 200-500 and 800-900, with repetitive mass difference patterns of m/z 12, 14, 16, and 18. This provided sound evidence that high-molecular-weight oligomers were generated as haze episodes became exacerbated. These oligomer signal intensities were enhanced in the presence of high relative humidity, aerosol water content, and PM (particles with an aerodynamic diameter ≤ 2.5 μm) mass, proving that the multiphase reaction processes play a fundamental role in haze formation in Beijing. Our study can form a basis for improved air pollution mitigation measures aimed at OA to improve health outcomes.
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http://dx.doi.org/10.1016/j.scitotenv.2020.141209DOI Listing
December 2020

THBS1 Is a Novel Serum Prognostic Factors of Acute Myeloid Leukemia.

Front Oncol 2019 7;9:1567. Epub 2020 Feb 7.

Medical Center of Hematology, Xinqiao Hospital, Army Medical University, Chongqing, China.

Dysregulation of cytokines and growth factors is a general feature of tumor microenvironment, and unraveling the expression spectrum of cytokine and growth factor in niche is of utmost importance. Here, we evaluated cytokine profiling of bone marrow serum samples in AML patients and healthy controls. Protein expression profiling of serum from nine AML patients and five healthy controls was obtained using a biotinylated antibody chip. A total of 507 cytokines and growth factors were analyzed. Compared with healthy people, AML patients expressed 31 signature proteins, among which, 27 were significantly higher expressed and 4 proteins were lower. When patients were divided into favorable and poor prognosis, 12 signature proteins were significantly differentially expressed between these two groups. Furthermore, in order to identify the accuracy of cytokine expression profiles, we verified and analyzed the expression of THBS1 (Thrombospondin 1) in 116 patients and 9 healthy people. We found that THBS1 was lowly expressed in AML patients, which might be induced by promoter methylation, and patients with low THBS1 possessed shorter survivor time. Our data indicated that we successfully unveil differentially expressed proteins in AML patients using a biotinylated antibody chip; among them, THBS1 may be a potential therapeutic target for AML patients' treatment.
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http://dx.doi.org/10.3389/fonc.2019.01567DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7020255PMC
February 2020

A sensitive two-step stacking by coupling field-enhanced sample injection and micelle to cyclodextrin stacking for the determination of neutral analytes.

J Chromatogr A 2020 May 7;1618:460854. Epub 2020 Jan 7.

College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, China. Electronic address:

To promote the detection sensitivity of neutral analytes, a sensitive two-step stacking strategy by coupling field-enhanced sample injection and micelle to cyclodextrin stacking in reverse migrating micelles MEKC has been established by selecting jujuboside A and B as models. The stacking mechanism, affecting factors as well as analytical performances of the proposed method were investigated. Compared with typical injection, the sensitivity enhancement factors of this method were up to 140- and 152-fold for jujuboside A and B, respectively. The enhancements were 8-10 times better than only single stacking strategy by MCDS. The LODs were 0.2-0.3 μg mL, interday and intraday%RSD were both lower than 4.3%, and a good linearity (r>0.999) was obtained. Feasibility in real samples analysis was evaluated by using Semen Ziziphi Spinosae dispensing granule and rat's urine. The results suggested that the strategy was simple, reliable, sensitive and promising for the analysis of neutral analytes in complex sample matrix.
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http://dx.doi.org/10.1016/j.chroma.2020.460854DOI Listing
May 2020

Mixed and intensive haze pollution during the transition period between autumn and winter in Beijing, China.

Sci Total Environ 2020 Apr 31;711:134745. Epub 2019 Oct 31.

State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing Key Laboratory of Indoor Air Quality Evaluation and Control, Tsinghua University, Beijing 100084, China.

In the Northern China Plain (NCP), extreme haze events with high concentrations of fine particles occur frequently during the winter but rarely occur in autumn. In this study, we present a synthetic analysis of particulate constituents during the historically polluted transition period of autumn-winter in 2018, revealing that mixed-type haze episodes are the result of regional transport, homogeneous/heterogeneous conversion, and sandstorm influences. The hydrolysis process of NO at higher relative humidity levels (>70%), which feature an enhanced nitrate oxidation ratio (0.30-0.70) and NO concentration (>60 μg m), was the driving factor for high PM mass concentrations during the observation periods. The long-distance transport of sandstorms, characterized by decreasing PM/PM ratios (<30%) from the north/northwest, is the most important factor for the explosive growth of PM concentration. These results can help us gain a comprehensive understanding of haze formation and highlight the importance of nitrate chemistry in the aqueous phase. The results suggest that persistent NO emission reduction measures must be made to better achieve air quality standards in Beijing and the NCP region.
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http://dx.doi.org/10.1016/j.scitotenv.2019.134745DOI Listing
April 2020

Tandem autologous hematopoietic stem cell transplantation for treatment of adult T-cell lymphoblastic lymphoma: a multiple center prospective study in China.

Haematologica 2021 01 1;106(1):163-172. Epub 2021 Jan 1.

Medical center of hematology, Xinqiao Hospital, Army Medical University, Chongqing, China.

T-cell lymphoblastic lymphoma (T-LBL) is a highly aggressive form of lymphoma with poor clinical outcomes and lacks of a standard treatment regimen. In this study, we assessed the safety and efficacy of tandem autologous hematopoietic stem cell transplantation (auto-HSCT) strategy for adult T-LBL and evaluated prognostic factors affecting survival. 181 Newly-diagnosed adult T-LBL patients were enrolled, 89 patients were treated with chemotherapy alone, 46 patients were allocated to single auto-HSCT group, 46 patients were treated with tandem auto-HSCT. The median follow-up time was 37 months, the 3-year progression/relapse rate of the tandem auto-HSCT group was significantly lower than that of the single auto-HSCT group and chemotherapy group (26.5% vs 53.1% and 54.8%). The 3-year PFS and OS rate of the tandem auto-HSCT group (73.5% and 76.3%) were significantly higher than those of the single auto-HSCT group (46.9% and 58.3%) and the chemotherapy group (45.1% and 57.1%). In the tandem auto-HSCT group, age and disease status after the first transplantation impacted the OS and PFS. Multivariate analysis identified that disease status after the first transplantation was the only independent prognostic factor for patients treated with tandem-HSCT. In addition, diagnostic models of the initial CD8+CD28+/CD8+CD28- T cell ratio in predicting the disease status were found to be significant. Taken together, tandem auto-HSCT can be considered an optimal strategy for adult T-LBL patients (ChiCTR-ONN-16008480).
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http://dx.doi.org/10.3324/haematol.2019.226985DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7776263PMC
January 2021

[Phenotypic and genetic analysis of a pedigree affected with hereditary FV deficiency due to a novel deletional variant of F5 gene].

Zhonghua Yi Xue Yi Chuan Xue Za Zhi 2019 Nov;36(11):1100-1103

The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325027, China.

Objective: To analyze the phenotype and F5 gene variant in a pedigree affected with hereditary coagulation factor V (FV) deficiency.

Methods: All of the exons, flanking sequences, and 5' and 3' untranslated regions of the F5 gene were subjected to PCR and direct sequencing. Suspected variant sites were confirmed by clone sequencing. Influence of the variants was predicted by using software including ClustalX and Mutation Taster.

Results: The prothrombin time (PT) and activated partial thromboplastin time (APTT) of the proband were prolonged to 20.3 s and 59.2 s, respectively, while FV activity (FV:C) and FV antigen (FV:Ag) were reduced by 13% and 17%, respectively. The FV:C and FV:Ag of his father, sister and daughter were decreased to 35%, 37%, 29% and 42%, 46%, 35%, respectively. The proband was found to carry a heterozygous c.2851delT variant in exon 13 of the F5 gene, which caused a frameshift and resulted in a truncated protein (p.Ser923LeufsX8). In addition, a heterozygous c.1538G to A (p.Arg485Lys) variant was found in exon 10. The father, sister and daughter of the proband all carried the p.Ser923LeufsX8 variant, while his mother and son carried the heterozygous p.Arg485Lys polymorphism. His younger brother and wife were of the wild type. Bioinformatic analysis showed that p.Ser923 was highly conserved across various species. Mutation Taster scored 1.00 for the p.Ser923LeufsX8 variant, and the result has predicted a corresponding disease.

Conclusion: A heterozygous deletional mutation c.2851delT in exon 13 of the F5 gene and a heterozygous c.1538G to A polymorphism harbored by the proband may be associated with the decreased FV level in this pedigree.
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http://dx.doi.org/10.3760/cma.j.issn.1003-9406.2019.11.011DOI Listing
November 2019

Focus on exosomes: novel pathogenic components of leukemia.

Am J Cancer Res 2019 1;9(8):1815-1829. Epub 2019 Aug 1.

Medical Center of Hematology, The Xinqiao Hospital of Army Medical University Chongqing, China.

Exosomes are released membrane vesicles derived from late endosomes, which share structural and biochemical characteristics with proteasomes. Exosomes are responsible for trafficking proteins, microRNAs (miRNAs), and long non-coding RNAs (lncRNAs) among cells and regulating various cellular processes, such as differentiation, proliferation, migration, invasion, and apoptosis. Although our knowledge of the roles of exosomes in the initiation and progression of leukemia is limited, some studies have indicated that exosomes can encompass many functional factors with an appropriate sorting signal, thereby supporting the metastasis, drug resistance, and immune escape of leukemia cells. This review initially focuses on the biogenesis and composition of exosomes and then summarizes the application of exosomes as a screening biomarker and a potential therapeutic target in leukemia. Many recent reports on the functions of exosomes released from leukemia cells are also discussed, including drug resistance, immune dysfunction, and microenvironment manipulation. Given the critical roles of exosomes in leukemia, understanding the mechanisms regulating the compositions and levels of exosomes, as well as defining exosome functions, will ultimately provide additional insights into the use of exosomes as therapeutic agents for leukemia treatment.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6726990PMC
August 2019

Chinese newborn screening for the incidence of G6PD deficiency and variant of G6PD gene from 2013 to 2017.

Hum Mutat 2020 01 23;41(1):212-221. Epub 2019 Sep 23.

Dongguan Newborn Screening Center, Dongguan Maternal & Infant Health Hospital, Dongguan, Guangdong, China.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common X-linked enzymopathies caused by G6PD gene variant. We aimed to provide the characteristics of G6PD deficiency and G6PD gene variant distribution in a large Chinese newborn screening population. We investigated the prevalence of G6PD in China from 2013 to 2017. Then, we examined G6PD activity and G6PD gene in representative Chinese birth cohort to explore the distribution of G6PD gene variant in 2016. We then performed multicolor melting curve analysis to classify G6PD gene variants in 10,357 neonates with activity-confirmed G6PD deficiency, and DNA Sanger sequencing for G6PD coding exons if hot site variants were not found. The screened population, organizations, and provinces of G6PD deficiency were increased from 2013 to 2017 in China. The top five frequency of G6PD gene variants were c.1376G>T, c.1388G>A, c.95A>G, c.1024C>T, and c.871G>A and varied in different provinces, with regional and ethnic features, and four pathogenic variant sites (c.152C>T, c.290A>T, c.697G>C, and c.1285A>G) were first reported. G6PD deficiency mainly occurs in South China, and the frequency of G6PD gene variant varies in different regions and ethnicities.
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http://dx.doi.org/10.1002/humu.23911DOI Listing
January 2020

Characteristics and formation mechanisms of winter haze in Changzhou, a highly polluted industrial city in the Yangtze River Delta, China.

Environ Pollut 2019 Oct 8;253:377-383. Epub 2019 Jul 8.

Kimoto Electric Co. Ltd, Funahashi-Cho, Tennouji-Ku, Osaka 543-0024, Japan.

Changzhou, an industrial city in the Yangtze River Delta, has been experiencing serious haze pollution, particularly in winter. However, studies pertaining to the haze in Changzhou are very limited, which makes it difficult to understand the characteristics and formation of winter haze in this area, and develop effective control measures. In this study, we carried out continuous online observation of particulate matter, chemical components, and meteorology in Changzhou in February 2017. Our results showed that haze pollution occurred frequently in Changzhou winter and exhibited two patterns: dry haze with low relative humidity (RH) and wet haze with high RH. Water-soluble inorganic ions (SO, NO, and NH) accounted for ∼52.2% of the PM mass, of which sulfate was dominant in wet haze periods while nitrate was dominant in other periods. With the deterioration of haze pollution, the proportion of nitrate in PM increased, while sulfate proportion increased under wet haze and decreased under dry haze. Dry haze and wet haze appeared under slow north wind and south wind, respectively, and strong north wind or sea breeze scavenged pollution. We found that formation of nitrate occurred rapidly in daytime with high concentrations of odd oxygen (O = O + NO), whereas formation of sulfate occurred rapidly during nighttime with high RH, indicating that photochemistry and heterogeneous reaction were the major formation mechanisms for nitrate and sulfate, respectively. Through the cluster analysis of 36-h backward trajectories, five sources of air masses from three directions were identified. High PM concentrations (84.1 μg m on average) usually occurred under the influence of two clusters (46%) from the northwest, indicating that regional transport from northern China aggravated the winter haze pollution in Changzhou. Emission reduction, particularly the mobile sources, and regional joint prevention and control can help to mitigate the winter haze in Changzhou.
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http://dx.doi.org/10.1016/j.envpol.2019.07.011DOI Listing
October 2019

Parameterization of heterogeneous reaction of SO to sulfate on dust with coexistence of NH and NO under different humidity conditions.

Atmos Environ (1994) 2019 Jul;208:133-140

State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.

Sulfate plays an important role in atmospheric haze in China, which has received considerable attention in recent years. Various types of parameterization methods and heterogeneous oxidation rates of SO have been used in previous studies. However, properly representing heterogeneous sulfate formation in air quality models remains a big challenge. In this study, we quantified the heterogeneous oxidation reaction using experimental results that approximate the haze conditions in China. Firstly, a series of experiments were conducted to investigate the heterogeneous uptake of SO with different relative humidity (RH) levels and the presence of NH and NO on natural dust surfaces. Then the uptake coefficients for heterogeneous oxidation of SO to sulfate at different RH under NH and NOcoexistence were parameterized based on the experimental results and implemented in the Community Multiscale Air Quality modeling system (CMAQ). Simulation results suggested that this new parameterization improved model performance by 6.6% in the simulation of wintertime sulfate concentrations for Beijing. The simulated maximum growth rate of SO during a heavy pollution period increased from 0.97 μg m h to 10.11 μg m h. The heterogeneous oxidation of SO in the presence of NH contributed up to 23% of the sulfate concentration during heavy pollution periods.
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http://dx.doi.org/10.1016/j.atmosenv.2019.04.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6559380PMC
July 2019

Biotoxicity of water-soluble species in PM using Chlorella.

Environ Pollut 2019 Jul 8;250:914-921. Epub 2019 Apr 8.

State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing Key Laboratory of Indoor Air Quality Evaluation and Control, Tsinghua University, Beijing, 100084, China.

China has been faced with severe haze pollution, which is hazardous to human health. Among the air pollutants, PM (particles with an aerodynamic diameter ≤ 2.5 μm) is the most dangerous because of its toxicity and impact on human health and ecosystems. However, there has been limited research on PM particle toxicity. In the present study, we collected daily PM samples from January 1 to March 31, 2018 and selected samples to extract water-soluble species, including SO, NO, WSOC, and NH. These samples represented clean, good, slight, moderate, and heavy pollution days. After extraction using an ultrasonic method, PM solutions were obtained. We used Chlorella as the test algae and studied the content of chlorophyll a, as well as the variation in fluorescence when they were placed into the PM extraction solution, and their submicroscopic structure was analyzed using transmission electron microscopy (TEM). The results showed that when the air quality was relatively clean and good (PM concentration ≤ 75 μg m), the PM extraction solutions had no inhibiting effects on Chlorella, whereas when the air quality was polluted (PM concentration > 75 μg m) and heavily polluted (PM concentration > 150 μg m), with increasing PM concentrations and exposure time, the chlorophyll a content in Chlorella decreased. Moreover, the maximum photochemical quantum yield (F/F) of Chlorella obviously decreased, indicating chlorophyll inhibition during polluted days with increasing PM concentrations. The effects on the chlorophyll fluorescence parameters were also obvious, leading to an increase of energy dissipated per unit reaction center (DI/RC), suggesting that Chlorella could survive when exposed to PM solutions, whereas the physiological activities were significantly inhibited. The TEM analysis showed that there were few effects on Chlorella cell microstructure during clean days, whereas plasmolysis occurred during light- and medium-polluted days. With increasing pollution levels, plasmolysis became more and more apparent, until the organelles inside the cells were thoroughly destroyed and most of the parts could not be recognized.
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http://dx.doi.org/10.1016/j.envpol.2019.04.017DOI Listing
July 2019

Haze formation indicator based on observation of critical carbonaceous species in the atmosphere.

Environ Pollut 2019 Jan 4;244:84-92. Epub 2018 Oct 4.

Kimoto Electric Co. Ltd, Funahashi-Cho, Tennouji-Ku, Osaka, 543-0024, Japan.

Organic aerosol (OA) are always the most abundant species in terms of relative proportion to PM concentration in Beijing, while in previous studies, poor link between carbonaceous particles and their gaseous precursors were established based on field observation results. Through this study, we provided a comprehensive analysis of critical carbonaceous species in the atmosphere. The concentrations, diurnal variations, conversions, and gas-particle partitioning (F-factor) of 8 carbonaceous species, carbon dioxide (CO), carbon monoxide (CO), methane (CH), volatile organic compounds (VOCs), non-methane hydrocarbon (NMHC), organic carbon (OC), elemental carbon (EC), and water soluble organic compounds (WSOCs), in Beijing were analyzed synthetically. Carbonaceous gases (CO, CO, VOCs, and CH) and OC/EC ratios exhibited double-peak diurnal patterns with a pronounced midnight peak, especially in winter. High correlation between VOCs and OC during winter nighttime indicated that OC was formed from VOCs precursors via an unknown mechanism at relative humidity greater than 50% and 80%, thereby promoting WSOC formation in PM and PM respectively. The established F-factor method was effective to describe gas-to-particle transformation of carbonaceous species and was a good indicator for haze events since high F-factors corresponded with enhanced PM level. Moreover, higher F-factors in winter indicated carbonaceous species were more likely to exist as particles in Beijing. These results can help gain a comprehensive understanding of carbon cycle and formation of secondary organic aerosols from gaseous precursors in the atmosphere.
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http://dx.doi.org/10.1016/j.envpol.2018.10.006DOI Listing
January 2019

Sulfate-nitrate-ammonium as double salts in PM: Direct observations and implications for haze events.

Sci Total Environ 2019 Jan 3;647:204-209. Epub 2018 Aug 3.

State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.

Obtaining detailed information on sulfate-nitrate-ammonium (SNA) is fundamentally important to explain the formation of haze in China, since it is a dominant component of fine particulate matter (PM) and plays a critical role in the deterioration of air quality. Several single-particle analysis methods have been applied to study and explain SNA formation; however, determining its mixture state remains a challenge. This study describes a direct observation of the SNA components in atmospheric particles on a single-particle scale, and details the first use of a non-destructive surface-enhanced Raman scattering (SERS) technique for SNA analysis. We studied PM collected at a site on the premises of Tsinghua University in Beijing, China, during a winter haze episode (12.15.2016-12.23.2016). The on-line data show that the SNA component accounted for 9.4% to 68.2% of the total mass of PM, becoming dominant on heavy haze days, and the sulfate concentration increased with the nitrate concentration (R = 0.72). Furthermore, the off-line SERS and scanning electron microscopy-energy dispersive X ray analysis (SEM-EDS) results for the single particles collected also indicated that SNA increase with increasing haze pollution. The existing state of the SNA component on each haze day was observed directly in a non-destructive manner mainly in the form of double salts such as 3(NHNO)·(NH)SO and 2(NHNO)·(NH)SO. A Raman mapping experiment further confirmed that the SNA was internally mixed. Our data also show that SNA can evaporate under high-vacuum scanning electron microscopy conditions, suggesting that SERS is an effective method to directly observe SNA without sample loss and may represent a promising single-particle technique to supplement traditional electron microscopy methods. This work will provide evidence for the SNA formation, particularly during haze events.
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http://dx.doi.org/10.1016/j.scitotenv.2018.07.107DOI Listing
January 2019

Case study of spring haze in Beijing: Characteristics, formation processes, secondary transition, and regional transportation.

Environ Pollut 2018 Nov 6;242(Pt A):544-554. Epub 2018 Jul 6.

Kimoto Electric Co. Ltd, Funahashi-Cho, Tennouji-Ku Osaka 543-0024, Japan.

Continuous haze monitoring was conducted from 12:00 3 April to 12:00 8 April 2016 in Beijing, China to develop a more detailed understanding of spring haze characteristics. The PM concentration ranged from 6.30 to 165 μg m with an average of 63.8 μg m. Nitrate was the most abundant species, accounting for 36.4% of PM, followed by organic carbon (21.5%), NH (19.3%), SO (18.8%), and elemental carbon (4.10%), indicating the key role of nitrate in this haze event. Species contribution varied based on the phase of the haze event. For example, sulfate concentration was high during the haze formation phase, nitrate was high during the haze, and secondary organic carbon (SOC) had the highest contribution during the scavenging phase. The secondary transition of sulfate was influenced by SO, followed by relative humidity (RH) and O (O+NO). Nitrate formation occurred in two stages: through NO oxidation, which was vulnerable to O; and by the partitioning of N (+5) which was susceptible to RH and temperature. SOC tended to form when O and RH were balanced. According to hourly species behavior, sulfate and nitrate were enriched during haze formation when the mixed layer height decreased. However, SOC accumulated prior to the haze event and during formation, which demonstrated the strong contribution of secondary inorganic aerosols, and the limiting contribution of SOC to this haze case. Investigating backward trajectories showed that high speed northwestern air masses following a straight path corresponded to the clear periods, while southwesterly air masses which traversed heavily polluted regions brought abundant pollutants to Beijing and stimulated the occurrence of haze pollution. Results indicate that the control of NO needs to be addressed to reduce spring haze. Finally, the correlation between air mass trajectories and pollution conditions in Beijing reinforce the necessity of inter-regional cooperation and control.
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http://dx.doi.org/10.1016/j.envpol.2018.07.001DOI Listing
November 2018

Targeting intracellular MMPs efficiently inhibits tumor metastasis and angiogenesis.

Theranostics 2018 15;8(10):2830-2845. Epub 2018 Apr 15.

Department of Pharmaceutics, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, P.R. China.

Treatment for metastatic cancer is a great challenge throughout the world. Commonly, directed inhibition of extracellular matrix metalloproteinases (MMPs) secreted by cancer cells can reduce metastasis. Here, a novel nanoplatform (HPMC NPs) assembled from hyaluronic acid (HA)-paclitaxel (PTX) prodrug and marimastat (MATT)/β-casein (CN) complexes was established to cure a 4T1 metastatic cancer model targeting CD44 and intracellular, rather than extracellular, MMPs. HPMC NPs were prepared by assembling the complexes and prodrug under ultrasonic treatment, which the interaction between them was evaluated by förster resonance energy transfer, circular dichroism and fluorescence spectra. The developed nanoplatform was characterized dynamic light scattering and transmission electron microscopy, and was evaluated in terms of MMP-sensitive release and stability. Subsequently, the cellular uptake, trafficking, and invasion were studied by flow cytometry, confocal laser microscopy and transwell assay. MMP expression and activity was determined by western blotting and gelatin zymography. Finally, the studies of biodistribution and antitumor efficacy were performed in a mouse 4T1 tumor breast model, followed by safety study in normal mouse. The interaction between the prodrug and complexes is strong with a high affinity, resulting in the assembly of these two components into hybrid nanoparticles (250 nm). Compared with extracellular incubation with MATT, HPMC NP treatment markedly reduced the expression (100%) and activity (50%) of MMPs in 4T1 cells and in the tumor. HPMC NPs exhibited 1.4-fold tumor accumulation, inhibited tumor-growth by >8-fold in volume with efficient apoptosis and proliferation, and suppressed metastasis (>5-fold) and angiogenesis (>3-fold). Overall, HPMC NPs were efficient in metastatic cancer therapy. According to the assembly of polymer prodrug and protein-drug complexes, this study offers a new strategy for constructing nanoparticles for targeted drug delivery, biomedical imaging, and combinatorial treatment. Importantly, inhibition of intracellular MMPs, metastasis and angiogenesis can be potently blocked, benefiting the rational design of nanomedicine for cancer treatment.
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http://dx.doi.org/10.7150/thno.23209DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5957012PMC
May 2019

Typical winter haze pollution in Zibo, an industrial city in China: Characteristics, secondary formation, and regional contribution.

Environ Pollut 2017 Oct 10;229:339-349. Epub 2017 Jun 10.

School of Resources and Environmental Engineering, Shandong University of Technology, Zibo 255049, Shandong Province, China.

Heavy haze pollution occurs frequently in northern China, most critically in the Beijing-Tianjin-Hebei area (BTH). Zibo, an industrial city located in Shandong province, is often listed as one of the top ten most polluted cities in China, particularly in winter. However, no studies of haze in Zibo have been conducted, which limits the understanding of the source and formation of haze pollution in this area, as well as mutual effects with the BTH area. We carried out online and continuous integrated field observation of particulate matter in winter, from 11 to 25 January 2015. SO, NO, and NH (SIA) and organics were the main constituents of PM, contributing 59.4% and 33.6%, respectively. With the increasing severity of pollution, the contribution of SIA increased while that of organics decreased. Meteorological conditions play an important role in haze formation; high relative humidity (RH) and low wind speed increased both the accumulation of pollutants and the secondary transition from gas precursors (gas-particle phase partitioning). Since RH and the presence of O can indicate heterogeneous and photochemistry processes, respectively, we carried out correlation analysis and linear regression to identify their relative importance to the three main secondary species (sulfate, nitrate, and secondary organic carbon (SOC)). We found that the impact of RH is in the order of SO > NO > SOC, while the impact of O is reversed, in the order of SOC > NO > SO, indicating different effect of these factors on the secondary formation of main species in winter. Cluster analysis of backward trajectories showed that, during the observation period, six directional sources of air masses were identified, and more than 90% came from highly industrialized areas, indicating that regional transport from industrialized areas aggravates the haze pollution in Zibo. Inter-regional joint prevention and control is necessary to prevent further deterioration of the air quality.
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http://dx.doi.org/10.1016/j.envpol.2017.05.081DOI Listing
October 2017

Characteristics of the secondary water-soluble ions in a typical autumn haze in Beijing.

Environ Pollut 2017 Aug 3;227:296-305. Epub 2017 May 3.

College of Resources and Environmental Sciences, China Agricultural University, Beijing 100094, China.

Four haze episodes (EPs) were observed in October 2014 in Beijing, China. For better understanding of the characteristics and the formation mechanisms of PM (particulate matter with an aerodynamic diameter ≤ 2.5 μm), especially secondary water-soluble inorganic species in these haze events, hourly concentrations of PM, sulfate, nitrate, and ammonium (SNA) were measured in this study. Concentrations of gaseous pollutants and meteorological parameters were also measured. The average concentration of PM was 106.6 ± 83.5 μg m, which accounted for around 53% of PM (particulate matter with an aerodynamic diameter ≤ 10 μm) mass. Nitrogen dioxide (NO) concentration was much higher than that of sulfur dioxide (SO) since October is a non-heating month. SNA is the most abundant secondary water-soluble inorganic species and contributed to 33% of PM mass concentration. Sulfur oxidation ratio (SOR) was much higher than nitrogen oxidation ratio (NOR). NOR and SOR increased with elevated PM levels and heterogeneous processes seemed to be the most plausible explanation of this increase. Relative humidity (RH), which is of great influence on aerosol liquid water content (ALWC), played a considerable role in the formation of secondary inorganic aerosols, accelerated the secondary transformation of gaseous precursors, and further aggravated haze pollution. The positive feedback loop associated with high aerosol levels and low planetary boundary layer (PBL) height led to the evolution and exacerbation of heavy haze pollution. Fire maps and 48-h air mass backward trajectories supported the significant impact of biomass burning activities and regional transport on haze formation over Beijing in October 2014.
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http://dx.doi.org/10.1016/j.envpol.2017.04.076DOI Listing
August 2017

Phase II Multicenter, Randomized, Double-Blind Controlled Study of Efficacy and Safety of Umbilical Cord-Derived Mesenchymal Stromal Cells in the Prophylaxis of Chronic Graft-Versus-Host Disease After HLA-Haploidentical Stem-Cell Transplantation.

J Clin Oncol 2016 08 11;34(24):2843-50. Epub 2016 Jul 11.

Lei Gao, Yanqi Zhang, Jia Liu, Peiyan Kong, Yao Liu, Li Gao, Cheng Zhang, Lidan Zhu, Qin Wen, Ping Wang, Xinghua Chen, Jiangfan Zhong, and Xi Zhang, Third Military Medical University, Chongqing; Baoyang Hu, Chinese Academy of Sciences, Beijing; Shifeng Lou, Second Affiliated Hospital of Chongqing Medical University, Chongqing; Yi Su, General Hospital of Chengdu Military Region of People's Liberation Army, Chengdu; Tonghua Yang, Yunnan Provincial People's Hospital; Huimin Li, Affiliated Hospital of Kunming Medical College, Kunming, China; and Jiangfan Zhong, University of Southern California, Los Angeles, CA.

Purpose: Although mesenchymal stromal cells (MSCs) possess immunomodulatory properties and exhibit promising efficacy against chronic graft-versus-host disease (cGVHD), little is known about the efficacy of MSCs in the prophylaxis of cGVHD after HLA-haploidentical hematopoietic stem-cell transplantation (HLA-haplo HSCT).

Patients And Methods: In this multicenter, double-blind, randomized controlled trial, we investigated the incidence and severity of cGVHD among patients, and the changes in T, B, and natural killer (NK) cells after the repeated infusion of MSCs.

Results: The 2-year cumulative incidence of cGVHD in the MSCs group was 27.4% (95% CI, 16.2% to 38.6%), compared with 49.0% (95% CI, 36.5% to 61.5%) in the non-MSCs control group (P = .021). Seven patients in the non-MSCs control group had severe lung cGVHD, but no patients in the MSCs group developed typical lung cGVHD (P = .047). After the MSC infusions, increasing memory B lymphocytes and regulatory T cells, as well as the ratio of type 1 T helper to type 2 T helper cells, were observed, whereas the number of NK cells decreased.

Conclusion: Our findings suggest that the repeated infusion of MSCs might inhibit cGVHD symptoms in patients after HLA-haplo HSCT, accompanied by changes in the numbers and subtypes of T, B, and NK cells, leading to the acquisition of immune tolerance.
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http://dx.doi.org/10.1200/JCO.2015.65.3642DOI Listing
August 2016

Antitumor activities and immunomodulatory of rice bran polysaccharides and its sulfates in vitro.

Int J Biol Macromol 2016 Jul 8;88:424-32. Epub 2016 Apr 8.

Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of Education, State Key Laboratory of Food Science and Technology, Collaborative Innovation Center for Food safety and quality control, Jiangsu province, National Engineering Laboratory for Cereal Fermentation Technology, School of Food Science and Technology, Jiangnan University, Wuxi, 214122,Jiangsu, China.

Polysaccharides purified from rice bran show antitumor activity against tumor cells, yet the mechanism of this action remains poorly understood. To address this issue, our study evaluated the effect of rice bran polysaccharides on mouse melanoma cell line B16, and Raw264.7 macrophages. Rice bran polysaccharides (RBP) failed to inhibit B16 cell growth in vitro. However, Raw264.7 macrophages treated by RBP enhancement of cytotoxic effects. The cytotoxicity was confirmed by the stimulation of nitric oxide (NO) production and tumor necrosis factor-α (TNF-α) secretion on Raw264.7 macrophages in a dose-dependent manner. RBP2, a fraction of RBP, notably enhanced the inhibition of B16 cells and boosted the immunepotentiation effect compared with RBP. To further enhance the inhibition of B16 cell growth, sulfated polysaccharides (SRBP) was derived using the chlorosulfonic acid-pyridine method. SRBP2 was found to suppress B16 cell growth, reduce B16 cell survival and stimulate NO and TNF-α production. However, SRBP2 displayed a cytotoxic effect on Raw264.7 macrophages. These results suggest that the antitumor activity of RBP and RBP2 is mediated mainly through the activation of macrophages. SRBP2 exerts its antitumor activity by inducing apoptosis in tumor cells and the secretion of NO and TNF-α.
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http://dx.doi.org/10.1016/j.ijbiomac.2016.04.016DOI Listing
July 2016

Multiple myeloma developing during long-term clinical course of refractory immune thrombocytopenic purpura: a case report and review of literature.

Int J Clin Exp Pathol 2015 1;8(11):15429-32. Epub 2015 Nov 1.

Department of Hematology, Xinqiao Hospital, Third Military Medical University Chongqing, China.

Immune thrombocytopenia (ITP) is an acquired, immune-mediated disease that is characterized by increased destruction of platelets by autoantibodies. Although the onset of the disease and clinical course are highly variable, the disease typically has a benign course. ITP associated with multiple myeloma (MM) has been rarely reported; it is even rarer for MM to develop during a long-term ITP (almost 20 years). Here, we first report on a case with a 20-year long clinical course of refractory ITP followed by newly diagnosed MM.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4713694PMC
October 2016

[Effects of SDF-1/CXCR4 signal pathway blockade by AMD3100 on the adhesion of leukemia cells to osteoblast niche and the drug resistance of leukemia cells].

Zhonghua Xue Ye Xue Za Zhi 2015 May;36(5):413-7

Department of Hematology, Xinqiao Hospital, The Third Military Medical University, Chongqing 400037, China.

Objective: To study the blocking effect of CXCR4 inhibitor AMD3100 on the adhesion of leukemia cells to osteoblast niche, and the reversal of multidrug resistance in leukemia cells.

Methods: Mesenchymal stem cells (MSCs) from leukemia patients were planted on the bio-derived bone scaffolds and then induced into osteoblasts to establish the bio-osteoblast niche. The levels of SDF-1were tested with ELISA. The leukemia cell line MV4-11 cells with FLT3-ITD mutation were inoculated into the bio-osteoblast niche to build a three-dimensional co- culture system. The expression level of CXCR4, adhesion and apoptosis rates of leukemia cells were observed by flow cytometry after incubation with AMD3100 and Ara-C for 24 h and 48 h.

Results: (1)The supernatant levels of SDF-1 in cultured osteoblast were (304 ± 18), (410 ± 28) and (396 ± 16) pg/ml on 7 th, 14 th and 21 th day, respectively. It reached the highest on 14 th day. The expression level of CXCR4 in cultured MV4-11 cells was (72 ± 16)%. (2)Adhesion rate of MV4-11 cells to osteoblast niche was (40.1 ± 8.1)% after AMD3100 treatment for 24 h, while that of control group was (65.6 ± 12.1)% (P<0.05). (3)The apoptosis rate of MV4-11 cells incubated with AMD3100 for 24 h was (5.6 ± 0.8)%, while that of control group was (2.5 ± 0.5)%. The apoptosis rates of AMD3100-induced MV4-11 cells were (10.0 ± 2.4)%, (17.8 ± 2.3)% and (25.1 ± 2.4)% after treatment with Ara-C at 0.02, 0.20, 2.00 mg/ml respectively and they were (6.7 ± 1.0)%, (10.3 ± 1.5)%, (16.2 ± 3.1)% respectively in AMD3100-noninduced control group, the difference was significant (P<0.05).

Conclusion: AMD3100 can block the interaction between osteoblasts niches and leukemia cells, and play an important role in the reversal of multidrug resistance in leukemia cells.
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http://dx.doi.org/10.3760/cma.j.issn.0253-2727.2015.05.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7342592PMC
May 2015