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1.
Molecules ; 24(19)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581527

RESUMO

The band shapes and band positions of near-infrared (NIR) and Raman spectra change depending on the concentrations of specific chemical functionalities in a multicomponent system. To elucidate these effects in more detail and clarify their impact on the analytical measurement techniques and evaluation procedures, NIR transmission spectra and Raman spectra of two organic liquid three-component systems with variable compositions were analyzed by two different multivariate calibration procedures, partial least squares (PLS) and classical least-squares (CLS) regression. Furthermore, the effect of applying different concentration units (volume percent (%V) and weight percent (%W) on the performance of the two calibration procedures have been tested. While the mixtures of benzene/cyclohexane/ethylbenzene (system 1) can be regarded as a blended system with comparatively low molecular interactions, hydrogen bonding plays a dominant role in the blends of ethyl acetate/1-heptanol/1,4-dioxane (system 2). Whereas system 1 yielded equally good calibrations by PLS and CLS regression, for system 2 acceptable results were only obtained by PLS regression. Additionally, for both sample systems, Raman spectra generally led to lower calibration performance than NIR spectra. Finally, volume and weight percent concentration units yielded comparable results for both chemometric evaluation procedures.

2.
Wei Sheng Yan Jiu ; 48(5): 795-798, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31601320

RESUMO

OBJECTIVE: To establish an effective method of primary and passage cultured cerebral cortical astrocyte of SD neonatal rat in vitro. METHODS: Cerebral cortex of two 2-day-old SD rats were taken with aseptic operation and then were cut to pieces. After stripped the pia mater, digested by 500 µL 0. 25% trypsin at 37 ℃ for 15 min. Next, dispersed cell suspension was made by mechanical method and filtered. Cell suspensions were incubated in an uncoated culture bottle at 37 ℃ for 15 min. The cells were inoculated at 5×10~6/m L in the T75 culture flask coated with L-polylysine. The cells were shaken at 200 r/min 37 ℃ for 18 h, then added 1 m L of trypsin to digest cells and then collected the cells. The morphology of the passage cells was observed under inverted phase contrast microscope, and the purity of astrocytes was identified by immunofluorescence staining of GFAP. The proliferate activity of passage cells was determined by MTS assay. RESULTS: The purity of astrocytes was( 97. 86 ± 0. 91) %, and the growth and proliferation activity of astrocytes were good after passage. CONCLUSION: A rapid, economical and effective method for obtaining astrocytes in the cerebral cortex of newborn rats was established.

3.
Nucleic Acids Res ; 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31544934

RESUMO

G-quadruplex (GQ) stabilizing small molecule (SM) ligands have been used to stabilize human telomeric GQ (hGQ) to inhibit telomerase activity, or non-telomeric GQs to manipulate gene expression at transcription or translation level. GQs are known to inhibit DNA replication unless destabilized by helicases, such as Bloom helicase (BLM). Even though the impact of SM ligands on thermal stability of GQs is commonly used to characterize their efficacy, how these ligands influence helicase-mediated GQ unfolding is not well understood. Three prominent SM ligands (an oxazole telomestatin derivative, pyridostatin, and PhenDC3), which thermally stabilize hGQ at different levels, were utilized in this study. How these ligands influence BLM-mediated hGQ unfolding was investigated using two independent single-molecule approaches. While the frequency of dynamic hGQ unfolding events was used as the metric in the first approach, the second approach was based on quantifying the cumulative unfolding activity as a function of time. All three SM ligands inhibited BLM activity at similar levels, 2-3 fold, in both approaches. Our observations suggest that the impact of SM ligands on GQ thermal stability is not an ideal predictor for their inhibition of helicase-mediated unfolding, which is physiologically more relevant.

5.
Biomed Res Int ; 2019: 7659239, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31485445

RESUMO

Background: The purpose of this study was to investigate the correlation of the extent of aortic arch calcification (AAC) detectable on chest X-rays with the severity of coronary artery disease (CAD) as evaluated by the SYNTAX score (SS) in patients with acute coronary syndrome (ACS). Methods: A total of 1,418 patients (344 women; 59 ± 10 years) who underwent coronary angiography for ACS and were treated with coronary revascularization were included in the present study; chest X-rays were performed on admission. The AAC extent was divided into four grades (0-3). SS was calculated based on each patient's coronary angiographic findings. The relationship between the AAC extent and SS was assessed. Results: The AAC extent was positively correlated with SS (ρ = 0.639, P < 0.001). In the multivariate analysis, compared with grade 0, odds ratios (ORs) of AAC grades 1, 2, and 3 in predicting SS >22 were 12.95 (95% CI, 7.85-21.36), 191.76 (95% CI, 103.17-356.43), and 527.81 (95% CI, 198.24-1405.28), respectively. Receiver operating characteristic curve analysis yielded a strong predictive ability of the AAC extent for SS >22 (area under curve = 0.840, P < 0.001). Absence of AAC had a sensitivity, specificity, positive prognostic value, negative prognostic value, and accuracy of 46.7%, 95.9%, 94.1%, 56.4%, and 67.3%, respectively, for SS ≤22. AAC grades ≥2 had a sensitivity of 66.3%, specificity of 89.2%, positive prognostic value of 81.5%, negative prognostic value of 78.6%, and accuracy of 79.6% for the correct identification of SS >22. Conclusions: The extent of AAC detectable on chest X-rays might provide valuable information in predicting CAD severity in ACS patients.

6.
Biomed Pharmacother ; 118: 109332, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545231

RESUMO

Atherosclerosis (AS), a severe disease characterized by an accumulation of lipids and fibers in the large arteries, is the most important contributor to ischemic stroke (IS). Although microRNAs (miRNAs) have been found in circulating blood, the role of miRNAs in the progression of AS remains unknown. In a previous study, we demonstrated that the spleen tyrosine kinase (Syk) gene plays a vital role in the process of IS. In the present study, we aimed to clarify whether the miRNAs targeting the Syk gene might slow the development of AS. Candidate miRNAs were screened in U937 and THP-1 cells via Bioinformatics analyses, RT-qPCR and dual-luciferase reporter assay. ApoE-/- mice were used as an AS animal model. RAAV transfection was performed to identify the roles of Syk gene and miRNAs in the development of AS in ApoE-/- mice. HE staining, Oil red O staining and immunohistochemistry were used to determine the mechanism of AS. RT-qPCR and western blotting were performed to determine the expressions of miRNAs and proteins, respectively. Over-expression of the Syk gene accelerated the development of AS. miR-377 effectively mediated the expression of the Syk gene in vitro and in vivo experiments. Further analysis indicated that over-expression of miR-377 partly alleviated the development of AS by down-regulating the expression of the Syk gene. This study identifies a novel role of miR-377 in AS via targeting Syk.

7.
Eur J Radiol ; 120: 108674, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31557718

RESUMO

PURPOSE: To compare the comfort levels of cone beam breast computed tomography (CBBCT) and digital mammography. MATERIALS AND METHODS: On 409 patients, CBBCT was performed within 1 week after conventional mammography. Patients evaluated their comfort by using an 11-point numerical rating scale (NRS-11) after completing the two examinations. The lower the score was, the more comfortable the examination modality was. The data was divided into different groups according to CBBCT scan mode (non-contrast mode, contrast-enhanced mode), age (≤44, 45∼59 and ≥60), body mass index (BMI) (<18.5 kg/m2, 18.5∼23.9 kg/m2, 24∼27.9 kg/m2 and ≥28 kg/m2), and breast density (fatty-breast, dense-breast) to evaluate the performance of CBBCT comfort in different groups and to analyse the influencing factor of patient comfort. The paired rank sum test was used to compare the comfort between CBBCT and mammography. RESULTS: Overall, the comfort of CBBCT was better than mammography (P < 0.05). CBBCT was more comfortable than mammography in both non-contrast and contrast-enhanced groups (P < 0.05). CBBCT was more comfortable than mammography in the ≤44, 45∼59 age groups (P < 0.05). There was no significant difference in the ≥60 age group (P = 0.5433). CBBCT was more comfortable than mammography in the BMI groups of 18.5∼23.9 kg/m2, 24∼27.9 kg/m2and ≥28 kg/m2 (P < 0.05). There was no significant difference in the <18.5 kg/m2 group (P = 0.43). CBBCT was more comfortable than mammography in both the fatty-breast and dense-breast groups (P < 0.05). CONCLUSION: The comfort of CBBCT was better than mammography.

8.
J Nat Prod ; 82(8): 2238-2245, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31415170

RESUMO

A phytochemical investigation of the aqueous EtOH extract of Bletilla striata tubers afforded 34 phenanthrene and 9,10-dihydrophenanthrene derivatives, including four new compounds, 1-4. These compounds were identified using physicochemical analyses and various spectroscopic methods. Twelve of these compounds were resolved into their enantiomers, and the absolute configurations were determined by comparison of experimental and calculated ECD spectra. The antineuroinflammatory activities were evaluated by measuring the inhibition of nitric oxide production in lipopolysaccharide-stimulated BV-2 microglial cells. Compounds 7, 32, and 33 displayed inhibitory activities, with IC50 values of 1.9, 5.0, and 1.0 µM, respectively, suggesting that they should be subjected to development as potential inhibitors of neuroinflammation.

9.
J Gastrointest Surg ; 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420860

RESUMO

BACKGROUND: Studies have demonstrated that multimodality therapy and surgery at high volume centers are associated with a longer survival. However, it is unknown if these data have translated into national changes in care delivery. METHODS: Patients with stages I-III pancreatic adenocarcinomas who underwent resections between 2004 and 2010 were identified from the National Cancer Data Base. The primary outcome was a 3-year overall survival. Temporal trends in survival outcomes and treatment variables were measured. A mediation analysis using the Lin method was used to discern the relative contribution of changes in treatment variables towards improvements in survival over time. RESULTS: A total of 22,196 patients were identified. Between 2004 and 2010, a 90-day peri-operative mortality remained unchanged (8.5 % to 8.4 %, p = 0.488), 3-year overall survival improved from 26 to 30% (p < 0.001), use of adjuvant/neoadjuvant chemotherapy increased (51 % to 61 %, p < 0.001), and more cases shifted to high volume centers (46 % at institutions performing > 10 cases/year in 2004 vs. 65 % in 2010, p < 0.001). On multivariable analysis, 32 % of the improvement in survival over time was attributable to receipt of chemotherapy, while 12 % was due to the shift of patients towards high volume centers (p < 0.001). CONCLUSIONS: Over the period from 2004 to 2010, a 3-year survival increased for patients undergoing resection for pancreatic cancer. This survival improvement can be partially attributed to the increasing utilization of chemotherapy and centralization of surgical care at high volume centers. A continued emphasis on these factors will likely result in further prolongation of a survival following resection.

10.
Sensors (Basel) ; 19(16)2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31426472

RESUMO

In this paper, a Multiple Input Multiple Output (MIMO) radar system based on a sparse-array is proposed. In order to reduce the side-lobe level, a genetic algorithm (GA) is used to optimize the array arrangement. To reduce the complexity of the system, time-division multiplexing (TDM) technology is adopted. Since the signals are received in different periods, a frequency migration will emerge if the target is in motion, which will lead to the lower direction-of-arrival (DOA) performance of the system. To solve this problem, a stretching transformation method in the fast-frequency slow-time domain is proposed, in order to eliminate frequency migration. Only minor adjustments need to be implemented for the signal processing, and the root-mean-square error (RMSE) of the DOA estimation will be reduced by about 90%, compared with the one of an uncalibrated system. For example, a uniform linear array (ULA) MIMO system with 2 transmitters and 20 receivers can be replaced by the proposed system with 2 transmitters and 12 receivers, achieving the same DOA performance. The calibration formulations are given, and the simulation results of the automotive radar system are also provided, which validate the theory.

11.
BMC Psychiatry ; 19(1): 260, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455294

RESUMO

BACKGROUND: Functional somatic symptoms in depression disorder may cause inappropriate illness behavior hindering the treatment process. Health anxiety may play a role in this relationship, but few studies have examined it. The current study aimed to investigate the role of health anxiety in the relationship between functional somatic symptoms and illness behavior in patients with depression. METHODS: The present study recruited 323 hospitalized patients with depression to complete the Patient Health Questionnaire-15, Whiteley-Index-7, and Scale for the Assessment of Illness Behavior, then constructed a structural equation model to examine whether health anxiety mediated the relationship between functional somatic symptoms and illness behavior. RESULTS: The results showed significant correlations between any two of the three variables of interest. More importantly, health anxiety played a partially mediating role (42.86%) in the relationship between functional somatic symptoms and illness behavior. Further analysis suggested that elderly patients reached higher health anxiety than younger patients when their functional somatic symptoms were mild. CONCLUSIONS: These results highlight that health anxiety may mediate the influence of functional somatic symptoms on illness behavior. The implications of assessing and intervening in health anxiety in patients with depression were discussed.

13.
Molecules ; 24(16)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426361

RESUMO

Key odorants of red wine made from the hybrid grapes of Marselan (Vitis vinifera L.) were isolated by solid-phase extraction (SPE) and explored by gas chromatography-olfactometry (GC-O) analysis. Application of aroma extract dilution analysis (AEDA) revealed 43 odor-active compounds, and 31 odorants among them were detected with flavor dilution (FD) factors ranging from 9 to 2187. Comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry (GC × GC-TOF-MS) were exploited to quantitate the aroma-active compounds with FD ≥9. The identification indicated ß-damascenone as having the highest FD factors, followed by eugenol, 2,3-butanedione, citronellol, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, phenethyl acetate, guaiacol, and 2-methoxy-4-vinylphenol. A total of 21 compounds were found to have odor activity values (OAVs) >1.0. Aroma reconstitution validation experiments showed a good similarity of blackberry, green pepper, honey, raspberry, caramel, smoky, and cinnamon aroma attributes between the original Marselan wine and the reconstructed wine. In addition, omission tests were carried out to further determine the contribution of odorants to the overall aroma.

14.
Microbiol Res ; 228: 126306, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31422233

RESUMO

The mariner transposon family of Himar1 has been widely used for the random mutagenesis of bacteria to generate single insertions into the chromosome. Here, a versatile toolbox of mariner transposon derivatives was generated and applied to the functional genomics investigation of fish pathogen Edwardsiella piscicida. In this study, we combined the merits of the random mutagenesis of mariner transposon and common efficient reporter marker genes or regulatory elements, mCherry, gfp, luxAB, lacZ, sacBR, and PBAD and antibiotic resistance cassettes to construct a series of derivative transposon vectors, pMmch, pMKGR, pMCGR, pMXKGR, pMLKGR, pMSGR, and pMPR, based on the initial transposon pMar2xT7. The function and effectiveness of the modified transposons were verified by introducing them into E. piscicida EIB202. Based on the toolbox, a transposon insertion mutant library containing approximately 3.0 × 105 distinct mutants was constructed to explore the upstream regulators of esrB, the master regulator of the type III and type VI secretion systems (T3/T6SS) in E. piscicida. Following analysis by Con-ARTIST, ETAE_3474, annotated as fabR and involved in fatty acid metabolism, was screened out and identified as a novel regulator mediating T3SS and T6SS expression. In addition, the fabR mutants displayed critical virulence attenuation in turbot. Due to the broad-range host compatibility of mariner transposons, the newly built transposon toolbox can be applied for functional genomics studies in various bacteria.

15.
Ann Otol Rhinol Laryngol ; : 3489419862581, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31311291

RESUMO

OBJECTIVES: We describe a new procedure for aspiration called tubed supraglottoplasty (TS). TS is a transoral procedure that approximates the aryepiglottic (AE) folds and arytenoids. This narrows the laryngeal inlet. This procedure has been used to improve swallowing and reduce aspiration in patients with vocal fold paralysis. We describe the technical aspects of TS and report on 11 patients. METHODS: TS is done by oral intubation followed by suspension laryngoscopy. An incision is made along the AE fold into the posterior commissure and then continued to the opposite AE fold. Dissection within this incision creates two mucosal flaps, one based on the laryngeal surface and the other on the pharyngeal surface. Two 1-cm releasing incisions are made at each end of the AE fold. The laryngeal mucosal flap is approximated using a 3-0 self-locking running suture. The pharyngeal mucosal flap is approximated as a second layer. This double-layered mucosal V-Y advancement flap builds up the posterior laryngeal height. It narrows and "tubes" the supraglottis. RESULTS: All patients tolerated TS without airway complications. Ten of the 11 patients reported improved swallowing function with less aspiration. Six of the 8 patients with prior G-tubes had their gastrostomy tube removed. Postoperative laryngoscopy showed a narrowed "tubed" supraglottis with a higher posterior wall preventing spillover and aspiration. An improved Functional Oral Intake Scale was recorded in ten of eleven patients. CONCLUSION: TS is a minimally invasive procedure that can improve swallowing and reduce aspiration.

16.
Sci Rep ; 9(1): 10707, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31341180

RESUMO

In order to study the molecular differences between type 2 diabetes mellitus (T2DM) and T2DM with depression (DD), we aimed to screen the differential expression of lncRNA, mRNA, and circRNA in the blood of patients with T2DM and DD. Based on the self-rating depression scale (SDS), patient health questionnaire 9 (PHQ9), blood glucose and HbA1c, we divided the patients into T2DM and DD group. Peripheral blood was collected from the two groups of patients to perform lncRNA, mRNA, and circRNA expression profiling and screening DD-related specific molecules. Subsequently, bioinformatics analysis was performed to investigate the functions of differentially expressed genes (DEgenes). Finally, RT-PCR and lncRNA-mRNA regulatory network was performed to verify the expressions of lncRNAs and mRNAs related to the occurrence and development of DD. 28 lncRNAs, 107 circRNAs, and 89 mRNAs were identified in DD differential expression profiles. GO and pathway analysis found that 20 biological process (BP) related entities and 20 pathways associated with DD. The analysis shows that the genes that are differentially expressed in the DD group involved in the development of the neuropsychiatric system, immunity, and inflammation. Then, we screening for the important DElncRNA and mRNA associated with DD were verified by RT-PCR experiments and the results of RT-PCR were consistent with the sequencing results. LncRNA, circRNA, and mRNA differential expression profiles exist in DD patients compared with T2DM. The lncRNA-mRNA regulatory network analysis confirmed the crosslinking and complex regulation patterns of lncRNA and mRNA expression and verified the authenticity of the regulatory network.

17.
Mol Med Rep ; 20(3): 2493-2499, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322213

RESUMO

Epidermal growth factor receptor kinase substrate 8 (EPS8) plays critical roles in a variety of solid tumors. However, the biologic functions and clinical significance of EPS8­like 3 (EPS8L3), an EPS8­related protein, in liver cancer remain unclear. To measure EPS8L3 expression in liver cancer cell lines, reverse transcription­quantitative PCR and western blot analyses were performed. The correlation between 338 patients with liver cancer and various clinicopathological factors obtained from the Oncomine database were evaluated using the χ2 test. Survival of patients with different expression of EPS8L3 was determined using Kaplan­Meier survival analysis with a log rank test, and Cox regression analysis was performed to estimate the prognostic significance of EPS8L3 expression. Additionally, cell proliferation and migration were determined using Cell Counting Kit­8 and wound healing assays. The results revealed that EPS8L3 expression was significantly upregulated in liver cancer tissues and cell lines (P<0.01), and that the expression of EPS8L3 was closely associated with grade (P=0.024) and mortality (P=0.011). Furthermore, survival analysis suggested patients with high EPS8L3 expression exhibited shorter survival compared with those with low EPS8L3 expression. Cox regression analysis indicated that EPS8L3 could be regarded as a prognostic biomarker in patients with liver cancer (hazard ratio, 1.58; 95% confidence interval, 1.085­2.301; P=0.017). Additionally, in vitro assays revealed that EPS8L3 depletion significantly inhibited liver cancer cell proliferation and migration, and reduced the levels of phosphorylated PI3K and AKT in the PI3K/AKT signaling pathway. Collectively, the results of the present study, for the first time to the best of our knowledge, demonstrated that EPS8L3 serves as an oncogene in liver cancer development; therefore, EPS8L3 may be a valuable prognostic predictor for patients with liver cancer.

18.
Sci Rep ; 9(1): 10670, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31337862

RESUMO

We prepared FeCoPt/SiO2 thin films by sol-gel spin-coating technique. As-prepared composite films were reduced in hydrogen to induce texture growth. Structural, magnetic property and surface morphology of the films were characterized by X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and scanning electron microscope (SEM). These experimental data indicate that integrated intensity ratio I(200)/I(110) of diffraction peaks (200) and (110) of FeCo firstly increases and then decreases, while the coercivity first decreases and then increases with increasing Pt doping content. The specimen with less Pt doping content has a large I(200)/I(110) value and small coervicity value, which is closely related with strong (200) texture in FeCo thin film. These results indicate that fcc-Pt is also in favor of promoting (200) FeCo texture like Al or Cu elements, and this similar trends of Pt and Al originate from their similar atomic radius and crystal cell volume.

19.
Plant Sci ; 286: 68-77, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31300143

RESUMO

Apple (Malus domestica) is an important fruit worldwide; however, the development of the apple industry is limited by fungal disease. Apple bitter rot caused by the pathogen Colletotrichum gloeosporioides is one of the most devastating apple diseases, leading to large-scale losses in apple quality and production. WRKY transcription factors have important functions in the regulation of biotic and abiotic stresses. However, their biological and molecular functions in non-model plants, including apple, remain poorly understood. Here, we isolated MdWRKY100 from 'Hanfu' apple. The MdWRKY100 protein fused to green fluorescent protein localized to the nucleus, and MdWRKY100 in yeast cells displayed transcriptional activation activity, which is consistent with the function of a transcription factor. Additionally, several putative cis-acting elements involved in abiotic stress responsiveness were also identified in the MdWRKY100 promoter. Transcriptional analysis revealed that MdWRKY100 was expressed ubiquitously in all examined apple organs. Overexpression in apple increased resistance to Colletotrichum gloeosporioides, while RNAi silencing transgenic plants were more sensitive to Colletotrichum gloeosporioides. Collectively, our data demonstrate that MdWRKY100 is a positive regulator of Colletotrichum gloeosporioides resistance in apple.


Assuntos
Colletotrichum/fisiologia , Resistência à Doença/genética , Malus/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Malus/metabolismo , Malus/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
20.
Sci Rep ; 9(1): 10376, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31316113

RESUMO

The surveillance of infectious diseases relies on the identification of dynamic relations between the infectious diseases and corresponding influencing factors. However, the identification task confronts with two practical challenges: small sample size and delayed effect. To overcome both challenges to imporve the identification results, this study evaluated the performance of dynamic Bayesian network(DBN) in infectious diseases surveillance. Specifically, the evaluation was conducted by two simulations. The first simulation was to evaluate the performance of DBN by comparing it with the Granger causality test and the least absolute shrinkage and selection operator (LASSO) method; and the second simulation was to assess how the DBN could improve the forecasting ability of infectious diseases. In order to make both simulations close to the real-world situation as much as possible, their simulation scenarios were adapted from real-world studies, and practical issues such as nonlinearity and nuisance variables were also considered. The main simulation results were: ① When the sample size was large (n = 340), the true positive rates (TPRs) of DBN (≥98%) were slightly higher than those of the Granger causality method and approximately the same as those of the LASSO method; the false positive rates (FPRs) of DBN were averagely 46% less than those of the Granger causality test, and 22% less than those of the LASSO method. ② When the sample size was small, the main problem was low TPR, which would be further aggravated by the issues of nonlinearity and nuisance variables. In the worst situation (i.e., small sample size, nonlinearity and existence of nuisance variables), the TPR of DBN declined to 43.30%. However, it was worth noting that such decline could also be found in the corresponding results of Granger causality test and LASSO method. ③ Sample size was important for identifying the dynamic relations among multiple variables, in this case, at least three years of weekly historical data were needed to guarantee the quality of infectious diseases surveillance. ④ DBN could improve the foresting results through reducing forecasting errors by 7%. According to the above results, DBN is recommended to improve the quality of infectious diseases surveillance.

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