Pre-operative enhanced magnetic resonance imaging combined with clinical features predict early recurrence of hepatocellular carcinoma after radical resection

BACKGROUND Indentifying predictive factors for postoperative recurrence of hepatocellular carcinoma(HCC)has great significance for patient prognosis.AIM To explore the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)enhanced magnetic resonance imaging(MRI)combined with clinical features in predicting early recurrence of HCC after resection.METHODS A total of 161 patients with pathologically confirmed HCC were enrolled.The patients were divided into early recurrence and non-early recurrence group based on the follow-up results.The clinical,laboratory,pathological results and Gd-EOB-DTPA enhanced MRI imaging features were analyzed.RESULTS Of 161 patients,73 had early recurrence and 88 were had non-early recurrence.Univariate analysis showed that patient age,gender,serum alpha-fetoprotein level,the Barcelona Clinic Liver Cancer stage,China liver cancer(CNLC)stage,microvascular invasion(MVI),pathological satellite focus,tumor size,tumor number,tumor boundary,tumor capsule,intratumoral necrosis,portal vein tumor thrombus,large vessel invasion,nonperipheral washout,peritumoral enhancement,hepatobiliary phase(HBP)/tumor signal intensity(SI)/peritumoral SI,HBP peritumoral low signal and peritumoral delay enhancement were significantly associated with early recurrence of HCC after operation.Multivariate logistic regression analysis showed that patient age,MVI,CNLC stage,tumor boundary and large vessel invasion were independent predictive factors.External data validation indicated that the area under the curve of the combined predictors was 0.861,suggesting that multivariate logistic regression was a reasonable predictive model for early recurrence of HCC.CONCLUSION Gd-EOB-DTPA enhanced MRI combined with clinical features would help predicting the early recurrence of HCC after operation.

内镜超声引导下胆道引流术治疗恶性梗阻性黄疸的应用

目的评价内镜超声引导下胆道穿刺引流(EUS-BD)治疗恶性胆道梗阻(MBO)的临床疗效及安全性。方法回顾性分析2016年1月-2019年1月该院行EUS-BD术治疗恶性梗阻性黄疸的21例患者的临床资料,探讨EUS-BD的疗效以及不良事件的发生情况。结果所有患者均接受了EUS-BD手术,16例获得技术成功(76.19%),其中15例(71.43%)获得临床治疗黄疸的效果,共发生3例不良事件(14.29%),该3例均在后续治疗中康复。结论EUS-BD是安全、有效的胆道引流方式,是ERCP失败后治疗MBO的可靠方式。

腹膜透析患者血清骨硬化蛋白水平及其影响因素分析

目的观察腹膜透析(PD)患者血清骨硬化蛋白水平变化,分析其相关的临床因素。方法选取2016年1月—2017年1月就诊于石河子大学第一附属医院及石河子人民医院肾内科行PD(透析时间>3个月)的患者78例作为实验组,同时选取石河子大学第一附属医院及石河子人民医院健康体检者78例作为对照组,所有入组对象均接受腹部平片检查,根据腹主动脉钙化评分(AACS)将PD患者分成轻度钙化组、中度钙化组及重度钙化组,收集相关生化指标,同时采用酶联免疫吸附实验检测血清成纤维细胞生长因子-23(FGF-23)、25-羟维生素D[25(OH)D]及骨硬化蛋白水平。结果 (1)实验组血清骨硬化蛋白、FGF-23水平均较对照组升高,25(OH)D水平较对照组降低(P <0.05);(2)随着钙化水平的逐渐加重,骨硬化蛋白、FGF-23、全段甲状旁腺激素(iPTH)、血磷、血肌酐(CREA)、尿酸、SBP、DBP等指标均升高(P <0.05),血清25(OH)D、血钙、肾小球滤过率(eGFR)均降低(P <0.05);(3) Pearson相关分析显示:血清骨硬化蛋白与年龄、血磷、iPTH、FGF-23、AACS、SBP及CREA均呈正相关(P <0.05),与25(OH)D、血钙及eGFR均呈负相关(P<0.05);(4) Logistic回归显示:AACS、eGFR、FGF-23、iPTH、血磷及25(OH)D是骨硬化蛋白的独立危险因素(P<0.05)。结论 PD患者血清骨硬化蛋白水平升高,其与AACS、eGFR、FGF-23、iPTH、血磷及25(OH)D明显相关。

Evaluation of HCPTd_1, d_(14)-double passaged intervening chemotherapy protocol for hepatocellular carcinoma

AIM. To establish a kind of standardization of the clinical chemotherapeutic prototypes for unresectable hepatocellular carcinomas （HCC）. METHODS： 10-Hydroxycamptothecin （HCPT） was applied through transcatheter arterial embolization （TAE） to HCC patients who were categorized into three groups： （1） test group： treatment with HCPT twice （HCPT dl and 14） through TAE and portal venous embolization. （2） Control Ⅰ： treatment with anticancer drugs without HCPT. （3） Control Ⅱ： treatment with HCPT as a major component in anticancer drugs once （HCPT dl）. A set of comparisons between test groups and control Ⅰ and Ⅱ groups were performed before and after the treatment to study the effectiveness of each treatment, in terms of tumor volumes, dynamic variations in serum alpha-fetoprotein （AFP）, gamma-glutamyl transferase hepatoma-specific band （GGT-Ⅱ）, patient survival and adverse events. RESULTS： The general effectiveness rate of the test group reached 62.1% （72/116）, remarkably higher than that of control Ⅰ （32.1%, 40/124） and control Ⅱ （54.7%, 47/56）, （P〈0.01 and P〈0.05, respectively）. Especially, the reduction rate or disappearance of the portal vein tumor emboli was as high as 88.4% （61/69） in the test group, in contrast with 13.9% （10/72） in control Ⅰ and 35.9% （18/51） in control Ⅱ （P〈0.01 and P〈0.01, respectively）. After treatment, AFP decreased or turned to negative levels at 52.3% （34/65） in control Ⅰ, 67.3% （35/52） in control Ⅱ, and 96.8% （60/62） in the test group. Also GGT-Ⅱ declined or became negative at 37.8% （28/74） in control Ⅰ, 69.5% （57/82） in control Ⅱ, and 94.7% （89/94） in test group （P〈0.01 and P〈0.05, respectively）. CONCLUSION： We have designed a good protocol （test group） to treat HCC with excellent advantages of high efficiency, low cost, low toxicity and low adverse events and easy application. It could be recommended as one of the standardizations for HCC treatment in clinical practice.

Intra-continental deformation and tectonic evolution of the West Junggar Orogenic Belt,Central Asia:Evidence from remote sensing and structural geological analyses

The West Junggar Orogenic Belt(WJOB)in northwestern Xinjiang,China,is located in the core of the western part of the Central Asian Orogenic Belt(CAOB).It has suffered two stage tectonic evolutions in Phanerozoic,before and after the ocean–continental conversion in Late Paleozoic.The later on intracontinental deformation,characterized by the development of the NE-trending West Junggar sinistral strike-slip fault system(WJFS)since Late Carboniferous and Early Permian,and the NW-trending Chingiz-Junggar dextral strike-slip fault(CJF)in Mesozoic and Cenozoic,has an important significance for the tectonic evolution of the WJOB and the CAOB.In this paper,we conduct geometric and kinematic analyses of the WJOB,based on field geological survey and structural interpretation of remote sensing image data.Using some piercing points such as truncated plutons and anticlines,an average magnitude of^73 km for the left-lateral strike-slip is calculated for the Darabut Fault,a major fault of the WJFS.Some partial of the displacement should be accommodated by strike-slip fault-related folds developed during the strike-slip faulting.Circular and curved faults,asymmetrical folds,and irregular contribution of ultramafic bodies,implies potential opposite vertical rotation of the Miao’ergou and the Akebasitao batholiths,resulted from the sinistral strike-slipping along the Darabut Fault.Due to conjugate shearing set of the sinistral WJFS and the dextral CJF since Early Mesozoic,superimposed folds formed with N–S convergence in southwestern part of the WJOB.

Complete Genomic Sequence of a Chinese Isolate of Duck Hepatitis Virus

The complete genomic sequence of Duck hepatitis virus 1(DHV-1) ZJ-V isolate was sequenced and determined to be 7 691 nucleotides(nt) in length with a 5'-terminal un-translated region(UTR) of 626 nt and a 3'-terminal UTR of 315 nt(not including the poly(A) tail).One large open reading frame(ORF) was found within the genome(nt 627 to 7 373) coding for a polypeptide of 2 249 amino acids.Our data also showed that the poly(A) tail of DHV-1 has at least 22 A's.Sequence comparison revealed significant homology(from 91.9% to 95.7%) between the protein sequences of the ZJ-V isolate and those of 21 reference isolates.Although DHV-1 has been classified as an unassigned virus in the Picornaviridae family,its genome showed some unique characteristics.DHV-1 contains 3 copies of the 2A gene and only 1 copy of the 3B gene,and its 3'-NCR is longer than those of other picornaviruses.Phylogenetic analysis to do sequence homology based on the VP1 protein sequences showed that the ZJ-V isolate shares high sequence homology with the reported DHV-1 isolates(from 92.9% to 99.2%),indicating that DHV-1 is genetically stable.

CTL Responses to Regulatory Proteins Tat and Rev in HIV-1 B’/C Virus-Infected Individuals

Objective To characterize HIV-1 specific CTL responses to regulatory proteins Tat and Rev in HIV-B＇/C virus-infected ART-naive individuals. Methods HIV-1-specific CTL responses were analyzed by IFN-7 ELISPOT assay using overlapping peptides spanning the consensus sequences of HIV-1 clade C Tat and Rev proteins. Statistical analysis and graphical presentation were performed using SIGMAPLOT 10.0 and SIGMASTAT 3.5. For samples with a positive response, the magnitude of CTL responses was compared between HIV-1 C proteins by Wilcoxon rank sum test, and the significance threshold was P〈0.05. Results Tat and Rev were frequently recognized, with 23% and 52% of the tested individuals having detectable responses to these proteins, respectively. Several immunodominant regions were detected in Rev. No significant correlation was observed between the magnitude and breadth of CTL responses to regulatory proteins and the control of virus replication in this study. Conclusion Tat and Rev can serve as targets for HIV-l-specific CTL, and several immunodominant regions are detectable in Rev. Further characterization of epitopes and their role in virus control may shed light on pathogenesis of HIV- 1 natural infection and also be useful for the design and testing of candidate vaccines.

Antidiarrheal properties of different extracts of Chinese herbal medicine formula Bao-Xie-Ning

OBJECTIVE： Bao-Xie-Ning （BXN）, a traditional Chinese herbal medicine （CHM） formula composed of Fructus Evodiae, Flos Caryophylli and Cortex Cinnamomi, and used for the treatment of infant diarrheal illness, was subject to systematic assessment for its putative multiple pharmacodynamic effects and pharmacological antidiarrheal mechanisms. METHODS： High-performance liquid chromatography-diode array detector-electrospray ionization- mass spectrometric/mass spectrometry was developed and validated for identification and quantification of the main constituents in different extracts of BXN. Male Kunming mice weighing 20 to 25 g were used for detecting the antidiarrheal activity of the extracts. Ethanolic extract （EE）, volatile oil extract （VOE）, and aqueous extract （AE） of BXN were respectively subjected to pharmacodynamic and pharmacological comparison in assessing antidiarrheal effects with senna-induced diarrhea, castor oil-induced diarrhea, acetic acid-induced writhing assay, and isolated duodenum test. RESULTS： The highest yields of three detected components of BXN, rutaecarpine, eugenol and cinnamaldehyde were observed in EE. EE showed the most remarkable antidiarrheal activity in dose-dependent and time-dependent manners in both senna- and castor oil-induced diarrhea models, and presented dose-dependent analgesic activity in acetic acid-induced algesthesia model. In addition, EE extract of BXN also exhibited strong antimobility action on the intestine and strongest depression on spontaneous contraction of isolated duodenum. CONCLUSION： Ethanol extraction is an efficient method to extract the active constituents of BXN. BXN extract demonstrated multiple pharmacological activities affecting the main mechanisms of diarrhea, which validated BXN＇s usage in the comprehensive clinical treatment of diarrhea.

Relationship of HLA-A,-Cw Polymorphisms with HIV/AIDS in Chinese Yi Ethnic Group of Sichuan Province

The relationship of HLA-A, -Cw alleles on HIV infection and AIDS disease progression in the Chinese Yi ethnic group of Sichuan province were investigated. The genetic polymorphisms of HLA-A, -Cw alleles of 102 unrelated healthy Chinese Yi ethnic individuals, 68 HIV-1 infected and 21 HIV positive long-time survivors were typed by PCR-SSP assay. Statistic signifiance was determined by the χ2 test with the SPSS software. No significant differences were observed between the HLA-A, -Cw alleles of the 68 HIV-1 infected and 102 non-infected Chinese Yi control individuals. Whereas the prevalence of A*3601,Cw*14(01-03)and Cw*0304 was significantly higher in 21 long time survivors compared with 102 healthy controls with P values of 0.016, 0.016 and 0.000 by χ2 or the Fisher exact test respectively. The result implies that A*3601,Cw*14(01-03) and Cw*0304 may be associated with slow AIDS disease progression in the Chinese Yi ethnic group, further studies on this association may yield insight on the pathogenesis of HIV-1 infection.

Modified membrane fixation technique in a severe continuous horizontal bone defect:A case report

BACKGROUND Continuous severe horizontal bone defect is common in the aesthetic maxillary anterior area,and presents a major challenge in implant dentistry and requires predictable bone augmentation to increase the width of the alveolar bone.CASE SUMMARY A 24-year-old man,with a history of well-controlled IgA nephropathy,presented to the Dentistry Department of our hospital complaining of missing his right maxillary anterior teeth 1 mo ago.Severe horizontal alveolar bone defects at sites of teeth 12,13 and 14 were diagnosed.A modified guided bone regeneration surgical approach stabilizing the absorbable collagen membrane and particulate graft materials by periosteal diagonal mattress suture(PDMS)combined with four corner pins was used for this severe continuous horizontal bone defect.The outcome revealed that the newly formed alveolar ridge dimension increased from 0.72 mm to 11.55 mm horizontally 10 mo postoperatively,with no adverse events.The implant surgery was successfully performed.CONCLUSION This case highlights that PDMS combined with four corner pins is feasible to maintain the space and stabilize the graft and membranes in severe continuous horizontal bone defect.

Development and future prospects of quantitative mineral assessment in China

Mineral potential assessment at the Earth’s surface has been an important research for geoscientists around the world in the past five decades. The fundamental aspects of mineral assessment at different scales can be associated with the following tasks, e.g., mineral potential mapping and estimation of mineral resources. This paper summarized the history and development in terms of theories, methods technologies and software platforms for quantitative assessment of mineral resources in China, e.g. comprehensive information methodology, geological anomaly, three-component quantitative prediction method, 5P orefinding area, integrated information assessment method, nonlinear process modeling and fractals, three dimensional mineral potential mapping, etc. At last, to discuss the future of quantitative mineral assessment in an era of big data including platform for 3D visualization, analysis and sharing, new methods and protocols for data cleaning, information enhancement, information integration, and uncertainties and multiple explanations of multi-information.

Study on Bone Mineral Density and its Influencing Factors among 1214 Older Adults in Xuhui District,Shanghai

Objective To understand the status of the forearm bone mineral density （BMD） in older adults, and to identify the potentialfactors influencing BMD. Methods A total of 1 214 older adults were examined, in Tianlin, Fenglin and Xietu sub-districts, of Xuhui district, Shanghai. BMD was tested at the left forearm, including distal radius and ulna 1/3 total, distal radius where the distance of radius and ulna is 8 mm, ultra-distal radius, by single energy X-ray densitometer. Results The BMD at all of the four sites decreased with the age increased. The average BMD was higher in male than in female for the same age and measured site. Distal radius 1/3 total had the highest BMD among the four sites. The incidence of low BMD and osteoporosis in distal forearm 1/3 radius total ascended with the age increased. Multiplied logistic regression showed that males had a lower risk to be low BMD （OR=0. 19） compared with female. Compared with the group aged from 50 to 54, the odds ratio in the group aged from 55 to 59, 60 to 64, and 65 to 70 were respectively 3.17, 5.13, 15.03. Compared with those whose monthly salary was less than 1 000, the odds ratio was O. 70 in those whose salary was more than 1 000. Conclusion The incidence of low BMD was high in older adults, and it is related with sex, age, monthly salary.

The evolution and functional divergence of 10 Apolipoprotein D-like genes in Nilaparvata lugens

Apolipoprotein D(ApoD),a member of the lipocalin superfamily of proteins,is involved in lipid transport and stress resistance.Whereas only a single copy of the ApoD gene is found in humans and some other vertebrates,there are typically several ApoD-like genes in insects.To date,there have been relatively few studies that have examined the evolution and functional differentiation of ApoD-like genes in insects,particularly hemi-metabolous insects.In this study,we identified 10 ApoD-like genes(NlApoD1−10)with distinct spatiotemporal expression patterns in Nilaparvata lugens(BPH),which is an important pest of rice.NlApoD1−10 were found to be distributed on 3 chromosomes in a tandem array of NlApoD1/2,NlApoD3−5,and NlApoD7/8,and show sequence and gene structural divergence in the coding regions,indicating that multiple gene duplication events occurred during evolution.Phylogenetic analysis revealed that NlApoD1−10 can be clustered into 5 clades,with NlApoD3−5 and NlApoD7/8 potentially evolving exclusively in the Delphacidae family.Functional screening using an RNA interference approach revealed that only NlApoD2 was essential for BPH development and survival,whereas NlApoD4/5 are highly expressed in testes,and might play roles in reproduction.Moreover,stress response analysis revealed that NlApoD3−5/9,NlApoD3−5,and NlApoD9 were up-regulated after treatment with lipopolysaccharide,H2O2,and ultraviolet-C,respectively,indicating their potential roles in stress resistance.

Chitin synthase 1 and five cuticle protein genes are involved in serosal cuticle formation during early embryogenesis to enhance eggshells in Nilaparvata lugens

Many holo-and hemimetabolous insects enhance their eggshells during embryogenesis by forming a serosal cuticle(SC).To date,scholarly understanding of the SC composition and SC-related gene functions has been limited,especially for hemimetabolous insects.In this study,we initially performed transmission electron microscopic(TEM)observation and chitin staining of the SC in Nilaparvata lugens,a hemimetabolous rice pest known as the brown planthopper(BPH).We confirmed that the SC was a chitin-rich lamellar structure deposited gradually during the early embryogenesis.Parental RNA interference(RNAi)against Nilaparvata lugens chitin synthase 1(NlCHS1)in newly emerged and matured females resulted in decreases of egg hatchability by 100%and 76%,respectively.Ultrastructural analyses revealed loss of the lamellar structure of the SC in dsNlCHS1-treated eggs.According to temporal expression profiles,five cuticle protein coding genes,NlugCpr1/2/3/8/90,were specifically or highly expressed during the SC formation period,and NlugCpr1/2/3/90 were further detected in 72 h eggshells extract by ultra-performance liquid chromatography-tandem mass spectrometry/mass spectrometry.NlugCpr2/3/90 were likely three SC-specific cuticle proteins.TEM observations of the SC following parental RNAi against NlugCpr1/2/3/8/90 demonstrated that NlugCpr3/8/90 were essential for SC formation.The study provided an understanding of the SC formation process and SC-related cuticle proteins in BPHs,which offer potential targets for pest control in the egg stage as well.

Identification of salivary proteins in the whitefly Bemisia tabaci by transcriptomic and LC-MS/MS analyses

The whitefly Bemisia tabaci is a notorious agricultural pest of many crops worldwide.Although it is thought that B.tabaci secretes saliva into the host plant to counter plant defenses,knowledge on the whitefly salivary proteome is limited.Here,we characterized the gene/protein repertoires of B.tabaci salivary glands and secreted saliva by transcriptomic and liquid chromatography tandem mass spectroscopy analyses.A total of 698 salivary gland-enriched unigenes and 171 salivary proteins were identified.Comparative analysis between the B.tabaci salivary proteins and those of different arthropod species revealed numerous similarities in proteins associated with binding,hydrolysis,and oxidation-reduction,which demonstrates a degree of conservation across herbivorous saliva.There were 74 proteins only identified in B.tabaci saliva,of which 34 were B.tabaci-specific.In addition,13 salivary proteins,of which I1 were B.tabaci-specific,were differentially regulated when B.tabaci fed on different hosts.Our results provide a good resource for future functional studies of whitefly salivary effectors,and might be useful in pest management.

Potential Clinical Risk of Inflammation and Toxicity from Rare-Earth Nanoparticles in Mice

Background： Nanotechnology is emerging as a promising tool to may pose a potential risk of toxicity during in vivo applications nanoparticles （RENPs） using mice as models. perform noninvasive therapy and optical imaging. Howevei; nanomedicinc In this study, we aimed to investigate the potential toxicity of rare-earth Methods： We synthesized RENPs through a typical co-precipitation method. Institute of Cancer Research （ICR） mice were randomly divided into seven groups including a control group and six experimental groups （10 mice per group）. [CR mice were intravenously injected with bare RENPs at a daily dose of 0, 0.5, 1.0, and 1.5 mg/kg for 7 days. To evaluate the toxicity of these nanoparticles in mice, magnetic resonance imaging （MRI） was performed to assess their uptake in mice. In addition, hematological and biochemical analyses were conducted to evaluate any impairment in the organ functions of ICR mice. The analysis of variance （ANOVA） followed by a one-way ANOVA test was used in this study. A repeated measures＇ analysis was used to determine any significant differences in white blood cell （WBC）, alanine aminotransferase （ALT）, and creatinine （CREA） levels at different evaluation times in each group. Results： We demonstrated the successful synthesis of two different sizes （10 nm and 100 nm） of RENPs. Their physical properties were characterized by transmission electron microscopy and a 980 nm laser diode. Results of MRI study revealed the distribution and circulation of the RENPs in the liver. In addition, the hematological analysis found an increase of WBCs to （8.69 ± 0.85） × 10^9/L at the 28^th day, which is indicative of inflammation in the mouse treated with 1.5 mg/kg NaYbF4：Er nanoparticles. Furthermore, the biochemical analysis indicated increased levels of ALT （[64.20 ± 15.50] U/L） and CREA （[27.80 ± 3.56] μmol/L） at the 28^th day, particularly those injected with 1.5 mg/kg NaYbF4：Er nanoparticles. These results suggested the physiological and pathological dalnage caused by these nanoparticles to the organs and tissues of mice, especially to liver and kidney. Conclusion： The use of bare RENPs may cause possible hepatotoxicity and nephritictoxicity in mice.

Couple＇s infertility in relation to male smoking in a Chinese rural area

Smoking is a well-known risk factor of reproductive health. However, the effect of paternal smoking on fertility has been less extensively examined. We conducted a cross-sectional study in a mountainous area of South-West China to assess the effect of male smoking on couples＇ fertility. A total of 8200 couples aged 18-49 years in the study area were invited to participate in the study. An in-person interview was performed to collect demographic characteristics of the couples, and husbands＇ life style factors including smoking and drinking habits. Information on time to pregnancy （TTP） was collected retrospectively. Infertility was defined as failure to achieve clinical pregnancy after regular unprotected intercourse for 〉12 months. Logistic regression model was used to estimate the association between male smoking and infertility. A total of 7025 couples were included in the final analysis. After adjusting for potential confounders, the couples were more likely to suffer from infertility if the husbands smoked （adjusted odds ratio [aOR] =1.28, 95% CI： 1.08-1.52） before the first pregnancy. After the analyses were performed according to husbands＇ smoking duration, an increased risk started at a relatively longer smoking duration of 5-10 years （aOR = 1.58, 95% CI. 1.26-1.99） and a stronger association （aOR = 3.34, 95% CI. 2.45-4.56） was observed in the group of 〉10 years. Similar patterns were found for the number of cigarettes smoked per day and the total amount of cigarettes smoked. From our findings, we conclude that male smoking may have an adverse impact on couples＇ infertility.

Learning Dynamic Causal Relationships Among Sugar Prices

In this paper, we are interested in exploring the dynamic causal relationships among two sets of three variables in different quarters. One set is futures sugar closing price in Zhengzhou futures exchange market （ZC）, spot sugar price in Zhengzhou （ZS） and futures sugar closing price in New York futures exchange market（NC） and the other includes futures sugar opening price in Zhengzhou （ZO）, ZS and NC. For each quarter, we first use Bayesian model selection to obtain the optimal causal graph with the highest BD scores and then use Bayesian model averaging approach to explore the causal relationship between every two variables. From the real data analysis, the two conclusions almost coincide, which shows that the two methods are practical.

Causal Analysis of Futures Sugar Prices in Zhengzhou

In this paper, we are interested in investigating the causal relationships among futures sugar prices in the Zhengzhou futures exchange market （ZF）, the spot sugar prices in Zhengzhou （ZS） and the futures sugar prices in New York futures exchange market （NF）. A useful tool called Bayesian network is introduced to analyze the problem. Since there are only three variables in our Bayesian network, the algorithm is straightforward： we display all the 25 possible network structures and adopt certain scoring metrics to evaluate them. We applied five different scoring metrics in total. Firstly, for each metric, we obtained 24 scores, each calculated from one of the 24 possible structures i.e. a Directed Acyclic Graph （DAG）. Then we eliminated the network structure which represents the independence of the three variables according to our prior knowledge concerning the futures sugar market. After that, the optimal network structure which implies the causal relationships was selected according to the corresponding scoring metric. Finally, after comparing the results from different scoring metrics, we obtained the relatively affirmative conclusion that ZS causes ZF from both the Bayesian Dirichlet （BD） metric, Bayesian Dirichlet-Akaike Information Criterion （BD-AIC） metric, Bayesian Dirichlet-Bayesian Information Criterion （BD-BIC） metric and Bayesian Information Criterion （BIC） metric. The conclusions that NF causes ZF and ZF causes ZS from the Akaike Information Criterion （AIC） metric and ZF causes ZS from the BIC metric were useful and significant to our investigation.

Rare-earth Nanoparticle-induced Cytotoxicity on Spatia Cognition Memory of Mouse Brain

Background： Luminescent rare-earth-based nanoparticles have been increasingly used in nanomedicine due to their excellent physicochemical properties, such as biomedical imaging agents, drug carriers, and biomarkers. However, biological sat）ty of the rare-earth-based nanomedicine is of great significance for future development in practical applications. In particular, biological effects of rare-earth nanoparticles on human＇s central nervous system are still unclear. This study aimed to investigate the potential toxicity of rare-earth nanoparticles in nervous system function in the case of continuous exposure. Methods： Adult ICR mice were randomly divided into seven groups, including control group （receiving 0.9% normal saline） and six experimental groups （ 10 mice in each group）. Luminescent rare-earth-based nanoparticles were synthesized by a reported co-precipitation method. Two different sizes of the nanoparticles were obtained, and then exposed to ICR mice through caudal vein injection at 0.5, 1.0, and 1.5 mg/kg body weight in each day for 7 days. Next, a Morris water maze test was employed to evaluate impaired behaviors of their spatial recognition memory. Finally, histopathological examination was implemented to study how the nanoparticles can affect the brain tissue of the ICR mice. Results： Two different sizes of rare-earth nanoparticles have been successfully obtained, and their physical properties including luminescence spectra and nanoparticle sizes have been characterized. In these experiments, the rare-earth nanoparticles were taken up in the mouse liver using the magnetic resonance imaging characterization. Most importantly, the experimental results of the Morris water maze tests and histopathological analysis clearly showed that rare-earth nanoparticles could induce toxicity on mouse brain and impair the behaviors of spatial recognition memory. Finally, the mechanism of adenosine triphosphate quenching by the rare-earth nanoparticles was provided to illustrate the toxicity on the mouse brain. Conclusions： This study suggested that long-term exposure of high-dose bare rare-earth nanoparticles caused an obvious damage on the spatial recognition memory in the mice.