2018 Vol. 31, No. 3

2018-03cover

2018, 31(3): 1-1.
2018-03contents

2018, 31(3): 2-2.
Original Articles
miR-93-5p Transferred by Exosomes Promotes the Proliferation of Esophageal Cancer Cells via Intercellular Communication by Targeting PTEN
LIU MengXin, LIAO Juan, XIE Ming, GAO ZhiKui, WANG XiangHu, ZHANG Ying, SHANG MuHe, YIN LiHong, PU YuePu, LIU Ran
2018, 31(3): 171-185. doi: 10.3967/bes2018.023
Objective To investigate the relationship between plasma miR-93-5p and the risk of esophageal cancer, as well as the influence of miR-93-5p on the biological function of esophageal cancer cells, exerted through exosomes. Methods The expression of plasma miR-93-5p in esophageal cancer patients and healthy controls was analysed by real-time quantitative PCR. The influence of miR-93-5p on the risk and prognosis of esophageal carcinoma was analyzed by conditional logistic regression and survival analysis. The effect of miR-93-5p on the biological function of recipient cells was investigated by establishing an in vitro donor cell co-culture model. The target gene of miR-93-5p was validated by luciferase reporter assay and Western Blotting. Results Upregulation of plasma miR-93-5p expression significantly increases the risk of esophageal cancer and is associated with poor prognosis. miR-93-5p transferred by exosomes promotes the proliferation of recipient esophageal cancer cells and affects the expression of PTEN and its downstream proteins p21 and cyclin D1. Conclusion Our study provides a reference for the identification of biomarkers for the diagnosis and prognosis of esophageal cancer.
YWHAZ Binds to TRIM21 but Is Not Involved in TRIM21-stimulated Osteosarcoma Cell Proliferation
ZENG Qing Zhong, LIU Wan Ting, LU Jun Lei, LIU Xiao Hui, ZHANG Yun Fang, LIU Lang Xia, GAO Xue Juan
2018, 31(3): 186-196. doi: 10.3967/bes2018.024
Objective Osteosarcoma is the most common type of malignant bone tumor in children and adolescents. The role of E3 ligases in tumorigenesis is currently a focus in tumor research. In the present study, we investigated the role of the E3 ligase tripartite motif 21 (TRIM21) in osteosarcoma cell proliferation. Methods 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays were used to assess osteosarcoma cell viability. U2-OS cells stably carrying a recombinant lentivirus expressing tetracycline-regulated TRIM21 were screened. Co-immunoprecipitation was coupled with LCMS/MS analysis to identify novel interacting partners of TRIM21. Co-immunoprecipitation and bimolecular fluorescence complementation (BIFC) were performed to validate the interactions between TRIM21 and its novel partner YWHAZ. A TRIM21-ΔRING construct was generated to test the effects of TRIM21 ligase activity on YWHAZ. Results TRIM21 positively regulated osteosarcoma cell proliferation. Overexpression of TRIM21 enhanced osteosarcoma cell tolerance toward various stresses. YWHAZ protein was identified as a novel interacting partner of TRIM21 and its expression levels were negatively regulated by TRIM21. The RING domain of TRIM21 was required for TRIM21 negative regulation of YWHAZ expression. However, overexpression of YWHAZ did not affect positive regulation of osteosarcoma cell proliferation by TRIM21. Conclusion Our results further clarify the molecular mechanisms underlying the pathogenesis of osteosarcoma.
Subchronic Oral Toxicity of Silica Nanoparticles and Silica Microparticles in Rats
LIANG ChunLai, XIANG Qian, CUI Wen Ming, FANG Jin, SUN Na Na, ZHANG Xiao Peng, LI Yong Ning, YANG Hui, YU Zhou, JIA Xu Dong
2018, 31(3): 197-207. doi: 10.3967/bes2018.025
Objective To investigate the subchronic oral toxicity of silica nanoparticles (NPs) and silica microparticles (MPs) in rats and to compare the difference in toxicity between two particle sizes. Methods Sprague-Dawley rats were randomly divided into seven groups:the control group; the silica NPs low-, middle-, and high-dose groups; and the silica MPs low-, middle-, and high-dose groups[166.7, 500, and 1, 500 mg/(kg·bw·day)]. All rats were gavaged daily for 90 days, and deionized water was administered to the control group. Clinical observations were made daily, and body weights and food consumption were determined weekly. Blood samples were collected on day 91 for measurement of hematology and clinical biochemistry. Animals were euthanized for necropsy, and selected organs were weighed and fixed for histological examination. The tissue distribution of silicon in the blood, liver, kidneys, and testis were determined. Results There were no toxicologically significant changes in mortality, clinical signs, body weight, food consumption, necropsy findings, and organ weights. Differences between the silica groups and the control group in some hematological and clinical biochemical values and histopathological findings were not considered treatment related. The tissue distribution of silicon was comparable across all groups. Conclusion Our study demonstrated that neither silica NPs nor silica MPs induced toxicological effects after subchronic oral exposure in rats.
TaqMan Real-time RT-PCR Assay for Detecting and Differentiating Japanese Encephalitis Virus
SHAO Nan, LI Fan, NIE Kai, FU Shi Hong, ZHANG Wei Jia, HE Ying, LEI Wen Wen, WANG Qian Ying, LIANG Guo Dong, CAO Yu Xi, WANG Huan Yu
2018, 31(3): 208-214. doi: 10.3967/bes2018.026
Objective To detect Japanese encephalitis virus (JEV) rapidly and distinguish its genotypes, a TaqMan-based reverse transcriptase quantitative polymerase chain reaction (RT-PCR) detection system was developed. Methods By aligning the full-length sequences of JEV (G1-G5), six sets of highly specific TaqMan real-time RT-PCR primers and probes were designed based on the highly conserved NS1, NS2, and M genes of JEV, which included one set for non-specific JEV detection and five sets for the detection of specific JEV genotypes. Twenty batches of mosquito samples were used to evaluate our quantitative PCR assay. Results With the specific assay, no other flavivirus were detected. The lower limits of detection of the system were 1 pfu/mL for JEV titers and 100 RNA copies/μL. The coefficients of variation of this real-time RT-PCR were all < 2.8%. The amplification efficiency of this method was between 90% and 103%. Conclusion A TaqMan real-time RT-PCR detection system was successfully established to detect and differentiate all five JEV genotypes.
Review
Therapeutic Potential of Anti-HIV RNA-loaded Exosomes
QIU Yong, MA Jing, ZENG Yi
2018, 31(3): 215-226. doi: 10.3967/bes2018.027
Letters to the Editor
The Relationship between Japanese Encephalitis and Environmental Factors in China Explored Using National Surveillance Data
HUANG Xiao Xia, YAN Lei, GAO Xiao Yan, REN Yu Huan, FU Shi Hong, CAO Yu Xi, HE Ying, LEI Wen Wen, LIANG Guo Dong, WANG Shi Wen, WANG Huan Yu
2018, 31(3): 227-232. doi: 10.3967/bes2018.028
Japanese encephalitis (JE) is a serious public health issue. This study was undertaken to better understand the relationship between JE distribution and environmental factors in China. JE data from 2005 to 2010 were retrieved from National Notifiable Disease Report System. ArcGIS, remote sensing techniques, and R software was used to exhibit and explore the relationship between JE distribution and environmental factors. Our results indicated that JE cases were mostly concentrated in warm-temperate, semitropical and tropical zones with annual precipitation > 400 mm; Broad-leaved evergreen forest, shrubs, paddy field, irrigated land, dryland, evergreen coniferous forest, and shrubland were risk factors for JE occurrence, and the former five were risk factors for counties with high JE incidence. These findings will inform the effective allocation of limited health resources such as intensive vaccination, surveillance and training in areas with high environmental risk factors.
A Cross-sectional Survey Assessing Carriage of Streptococcus pneumoniae in a Healthy Population in Xinjiang Uygur Autonomous Region of China
XIE Na, CHEN Zhao Yun, CHEN Tao, ZHU Bing Qing, XU Li, GAO Yuan, ZHANG Ai Yu, ZHAO Pan, LIU Ji Wen, SHAO Zhu Jun
2018, 31(3): 233-237. doi: 10.3967/bes2018.029
The carriage rate and serotype distribution of Streptococcus pneumoniae (S. pneumoniae) in a healthy population in China remains unclear. In this study, we collected the oropharyngeal swabs from 513 individuals in Xinjiang, China. Real-time PCR targeting the lytA gene and 12 serotypes were assessed to identify S. pneumoniae carriage. The total carriage rate of S. pneumoniae was 70.4% (361/513). The most prevalent serotypes were 19B/F, 18B/C, 5, and 6A/B. The highest carriage rate of S. pneumoniae was noted in children aged 6-10 years (88.6%), which merits further attention. The co-colonization rate of two or more S. pneumoniae serotypes was 79.8% (264/331). This study aimed to investigate the baseline pneumococcal carriage rate among healthy individuals in China to improve our understanding of the epidemiology of S. pneumoniae.
The Taxonomic Status of Spermophilus in the Plague Area of Dingbian County, Shaanxi Province, China
AN Cui Hong, CHEN Bao Bao, FAN Suo Ping, SUN Yang Xin, LYU Wen, SHE Jian Jun
2018, 31(3): 238-241. doi: 10.3967/bes2018.030
This study was conducted to define the taxonomic status of Spermophilus in the plague area of Dingbian County in Shaanxi Province, China, through the two-factor variance analysis of morphological characteristics, DNA barcoding, and chromosome karyotype analysis. The Spermophilus samples collected from Dingbian and Zhengxiang Baiqi Counties exhibited significant differences in their morphological measurements. All Spermophilus samples form two distinct branches in neighbor-joining (NJ) tree. One branch included the Spermophilus samples collected from Inner Mongolia, and the other branch included samples collected from the plague foci of Shaanxi Province and the Ningxia Region. The Spermophilus samples collected from Dingbian County had a chromosome number of 2n = 38 in 84.40% of all their cells. The Spermophilus species collected from the plague area of Dingbian County was categorized as Spermophilus alashanicus (S.alashamicus). The findings reported in this study are epidemiologically significant for monitoring plague in this region of west-central China.
Case Control Study of Impulsivity, Aggression, Pesticide Exposure and Suicide Attempts Using Pesticides among Farmers
LYU Chun Ping, PEI Jian Ru, BESELER L. Cheryl, LI Yu Ling, LI Jian Hui, REN Ming, STALLONES Lorann, REN Shu Ping
2018, 31(3): 242-246. doi: 10.3967/bes2018.031
A case-control study was conducted to investigate associations between organophosphate pesticide (OP) exposure, aggression, impulsivity, and attempted suicide. Questionnaires were used to collect information; impulsivity and aggression were measured by the Barratt Impulsivity Scale (BIS) and the Aggression Inventory (AI). A greater number of OP symptoms was associated with an increased odds of a suicide attempt after adjusting for marital status and income (OR = 1.45; CI 1.14-1.86). Attempted suicide was significantly associated with high impulsivity scores (means: 72.4 vs. 60.6, P < 0.0001) and high aggression scores (means: 38.5 vs. 26.1, P < 0.0001). Suicide attempters had a higher number of OP exposure symptoms than controls and scored higher on scales of impulsivity and aggression.
Inhibition of Erythroid Differentiation of Human Leukemia K562 Cells by N-acetylcysteine and Ascorbic Acid through Downregulation of ROS
YU Chun Hong, JIANG Liang, WANG Ying, CUI Ning Xuan, ZHAO Xiao, YI Zong Chun
2018, 31(3): 247-251. doi: 10.3967/bes2018.032
This study investigated the effects of N-acetylcysteine (NAC) and ascorbic acid (AA) on hemin-induced K562 cell erythroid differentiation and the role of reactive oxygen species (ROS) in this process. Hemin increased ROS levels in a concentration-dependent manner, whereas NAC and AA had opposite effects. Both NAC and AA eliminated transient increased ROS levels after hemin treatment, inhibited hemin-induced hemoglobin synthesis, and decreased mRNA expression levels of β-globin, γ-globin, and GATA-1 genes significantly. Pretreatment with 5, 000 μmol/L AA for 2 h resulted in a considerably lower inhibition ratio of hemoglobin synthesis than that when pretreated for 24 h, whereas the ROS levels were the lowest when treated with 5, 000 μmol/L AA for 2 h. These results show that NAC and AA might inhibit hemin-induced K562 cell erythroid differentiation by downregulating ROS levels.