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Perinatal and childhood adverse outcomes associated with assisted reproductive technology (ART) has been reported, but it remains unknown whether the initial leukocyte telomere length (LTL), which is an indicator of age-related phenotypes in later life, is affected. Here, we estimated the LTLs of 1,137 individuals from 365 families, including 202 children conceived by ART and 205 children conceived spontaneously from two centers of the China National Birth Cohort, using whole-genome sequencing (WGS) data. One-year-old children conceived by ART had shorter LTLs than those conceived spontaneously (beta, -0.36; P = 1.29 × 10

Mosaic chromosomal alterations (mCAs) detected from blood-derived DNA are large structural alterations of clonal haematopoietic origin and are associated with various diseases, such as haematological malignancies, infections, and solid cancers. We aimed to investigate whether mCAs contribute to the risk of lung cancer and modify the effect of polygenic risk score (PRS) on lung cancer risk prediction.The blood-derived DNA of patients with lung cancer and cancer-free controls with Chinese ancestry from the Nanjing Lung Cancer Cohort (NJLCC) study were genotyped with a Global Screening Array, and mCAs were detected with the Mosaic Chromosomal Alterations (MoChA) pipeline. mCA call sets of individuals with European ancestry were obtained from the prospective cohort UK Biobank (UKB) study, including documented incident lung cancer. All patients with lung cancer from the NJLCC study (aged 15 years or older at diagnosis) were histopathologically confirmed as new lung cancer cases by at least two pathologists and were free of chemotherapy or radiotherapy before diagnosis. Participants with incident lung cancer (aged 37-73 years at assessment) diagnosed after recruitment to the UKB were identified through linkage to national cancer registries. Logistic regression and Cox proportional hazard models were applied to evaluate associations between mCAs and risk of lung cancer in the NJLCC (logistic regression) and UKB (Cox proportional hazard model) studies.The NJLCC study included 10 248 individuals (6445 [62·89%] men and 3803 [37·11%] women; median age 60·0 years [IQR 53·0-66·0]) with lung cancer and 9298 individuals (5871 [63·14%] men and 3427 [36·86%] women; median age 60·0 years [52·0-65·0]) without lung cancer recruited from three sub-regions (north, central, and south) across China between April 15, 2003, and Aug 18, 2017. The UKB included 450 821 individuals recruited from 22 centres across the UK between March 13, 2006, and Nov 1, 2010, including 2088 individuals with lung cancer (1075 [51·48%] men and 1013 [48·52%] women; median age 63·0 years [IQR 59·0-66·0]), and 448 733 participants were free of lung cancer (204 713 [45·62%] men and 244 020 [54·38%] women; median age 58·0 years [IQR 50·0-63·0]). Compared with non-carriers of mosaic losses, carriers had a significantly increased risk of lung cancer in the NJLCC (odds ratio [OR] 1·81, 95% CI 1·43-2·28; p=6·69 × 10mCAs act as a new endogenous indicator for the risk of lung cancer and might be jointly used with PRS to optimise personalised risk stratification for lung cancer.National Natural Science Foundation of China, Outstanding Youth Foundation of Jiangsu Province, Natural Science Foundation of Jiangsu Province, and Postdoctoral Science Foundation of China.For the Chinese translation of the abstract see Supplementary Materials section.

Caverns are generally formed by a combination of regional geological action and groundwater, and their improper treatment will inevitably lead to dangerous conditions in underground works. To detect the specific failure mechanism of tunnel-surrounding rock induced by invisible caverns, a true triaxial compression test is conducted, accompanied by acoustic emission technology and an internal borehole camera, for monitoring the acoustic response and visible secondary cracks, and a corresponding DEM simulation is carried out to reveal the meso-mechanism. The results indicate the following: (1) The invisible cavern demonstrates a negative influence on the stability of the tunnel and leads to a 25.82% reduction in the peak z-axis load of the specimens. (2) The acoustic emission results show that the relatively severe dominant failures mainly occur near the peak stress in all types of specimens, and the speed and intensity of the cavern-existing specimen is significantly greater than that of the cavern-free specimen. (3) The cavity-free tunnel shows mirror-symmetric splitting failure on the left and right sidewalls, while the secondary cracks appear earlier and show asymmetrical distribution in the cavern-existing specimen, and the volume of broken rock blocks near the free surface is larger. (4) The cavern directly changes the failure process of the tunnel-surrounding rock (intermediate rock failure occurs earlier than splitting failure), the distribution of principal stress, and the corresponding mechanism of secondary failures. (5) Application of the displacement and velocity trend fields helped to reveal accurate failure procedures in the true triaxial test.

Background: Interstitial fibrosis and tubular atrophy (IFTA) are the histopathological manifestations of CKD and one of the causes of long-term renal loss in transplanted kidneys. The purpose of our study is to screen IFTA-related genes with higher importance scores through Random Forest (RF) and further construct IFTA diagnostic model through Artificial Neural Networks (ANNs). Methods: We screened all 162 “kidney transplant” related cohorts in the GEO database and obtained 5 data sets (training sets: GSE98320 validation sets: GSE22459, GSE53605 and GSE76882 survival sets: GSE21374). Differentially expressed genes (DEGs) analysis, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Random Forest (RF), Artificial Neural Network (ANN), Unsupervised Clustering analysis, CIBERSORT analysis were used to analyze the data. Results: A total of 108 common DEGs were identified by taking the intersection of the DEGs of our training sets and validation sets. A total of 15 top IFTA-specific DEGs were screened through the RF, then was used to build ANNs models. The model has good performance in both the training sets [GSE98320 (AUC = 0.9560)] and the validation sets [GSE22459 (AUC = 0.720), GSE53605 (AUC =0.938), GSE76882 (AUC = 0.781)], indicating that we have avoided overfitting while improving the accuracy. Furthermore, samples of survival sets are divided into two clusters using consensus clustering algorithm basing on the expression of 15 top IFTA-specific DEGs. We found significant differences between the two subgroups by survival analysis, and further enrichment analysis and immune cell infiltration analysis were conducted to further explore the causes of survival differences. Conclusion: we identified key biomarkers of IFTA and developed a new IFTA classification model, basing on the combination of RF and ANNs.

Super-enhancers (SEs) are important transcriptional regulators in tumorigenesis; however, the functional characterization and clinical significance of SEs in lung adenocarcinoma (LUAD) remain unclear. By using H3K27ac ChIP-seq data of two LUAD cell lines and eight lung tissues, we detected 1045 cancer-specific and 5032 normal-specific SEs. Compared to normal-specific SEs, cancer-specific SEs have different regulatory mechanisms where associated target genes were enriched in critical tumor-related pathways and tended to be regulated by transcription factors of Fos Proto-Oncogene, AP-1 Transcription Factor Subunit and Jun Proto-Oncogene, AP-1 Transcription Factor Subunit families. By using expression data of 513 LUAD and 57 adjacent samples from The Cancer Genome Atlas and 80 tumor-normal paired LUAD samples from the Nanjing Lung Cancer Cohort study, we performed differential expression analysis of target genes for SEs and defined 243 crucial SEs. Unsupervised clustering of crucial SEs revealed two subtypes with different levels of genomic aberrations (i.e., mutation and copy number alteration) and clinical outcomes (progression-free interval: p = 0.030; disease-free interval: p = 0.047). In addition, patients with adverse clinical outcomes were more sensitive to three small molecule inhibitors (bortezomib, doxorubicin, and etoposide), and their targets (PSMB5 and TOP2A) also have elevated expression levels among these patients. Taken together, our findings provided a comprehensive characterization of SEs in LUAD and emphasized their clinical significance in LUAD therapy.

Ethylene carbonate solutions dissolving mixed lithium salts composed of both difluoro(oxalato)borate (DFOB

To improve the weaknesses of large leakage and wear of dual-rotor intershaft labyrinth seal in aero-engines, the cylindrical gas film seal of metal rubber with a compliant feature is proposed to substitute this conventional seal. According to the dual-rotor operating condition, an analysis method of gas film pressure is presented considering the complex condition of rotor tilt, centrifugal expansion effect, and rotor circular precession. The characteristics of gas film pressure distribution are computed and comparisons are conducted in a complex operating state that the tilt rotor is in forward/backward circular precession under a homodromous/counter-rotating condition with/without the influence of centrifugal expansion. Besides, the formation mechanism of the gas film pressure caused by rotor rotational direction and circular precession direction is revealed. Also, the influence of rotor speed and seal ring speed on gas film pressure is analyzed when the rotor is tilted. The results indicate that for the dual-rotor cylindrical gas film seal with high rotating speed, the rotor tilt and centrifugal expansion effect have significant influence on the gas film pressure distribution, and the rotors’ rotational direction as well as rotor circular precession direction determines the maximum gas film pressure distribution area. The maximum pressure under a homodromous condition with backward precession is the highest; the maximum pressure under a homodromous condition with forward precession is the lowest. The former is 1.33% and 1.68% higher than the latter, respectively, with/without consideration of centrifugal expansion. The study method, which is generally suitable for the cylindrical gas film seal with single-rotor/dual-rotor, lays the foundation of performance analysis under complex operating conditions.

Mammalian inositol 1,4,5-trisphosphate receptor (ITPR) genes encode ubiquitously expressed endoplasmic reticulum CaIn the present case-control study, 12 SNPs in the potential functional regions of the ITPR1, ITPR2, and ITPR3 genes were genotyped using an Illumina Infinium® Beadchip in 2095 Chinese women (1032 cases and 1063 controls).Multivariate logistic regression analyses indicated that a missense SNP in the ITPR3 coding region (rs2229642) was significantly related to breast cancer risk when using an additive model in this study (rs2229642-adjusted odds ratio = 1.40, 95% confidence interval = 1.12-1.74, p = 2.97 × 10The results indicated that genetic variant in the coding region of ITPR3 gene may regulate the expressions of its host and some other cancer-related genes, as well as act as potential predictive biomarker for susceptibility to breast cancer in the Chinese population.

The fault tree (FT) is a practical graphical analysis model that describes how faults propagate in the system and how component failures can cause system failures. However, improper disposal of the tailings industrial system (TIS) will bring great risks to enterprises and individuals. Therefore, this study first faces the life cycle of TIS, builds a fault tree model of TIS failure and accident evolution based on evidence, and then establishes a failure prevention framework. Finally, this framework is applied to actual case studies to provide preventive measures.

Ribonucleotide reductase (RNR) is the key enzyme that catalyzes the production of deoxyribonucleotides (dNTPs) for DNA replication and it is also essential for cancer cell proliferation. As the RNR inhibitor, Gemcitabine is widely used in cancer therapies, however, resistance limits its therapeutic efficacy and curative potential. Here, we identified that mTORC2 is a main driver of gemcitabine resistance in non-small cell lung cancers (NSCLC). Pharmacological or genetic inhibition of mTORC2 greatly enhanced gemcitabine induced cytotoxicity and DNA damage. Mechanistically, mTORC2 directly interacted and phosphorylated RNR large subunit RRM1 at Ser 631. Ser631 phosphorylation of RRM1 enhanced its interaction with small subunit RRM2 to maintain sufficient RNR enzymatic activity for efficient DNA replication. Targeting mTORC2 retarded DNA replication fork progression and improved therapeutic efficacy of gemcitabine in NSCLC xenograft model in vivo. Thus, these results identified a mechanism through mTORC2 regulating RNR activity and DNA replication, conferring gemcitabine resistance to cancer cells.

Mg-doped HAP aerogel (MHAPA) was firstly in situ prepared via freeze-drying-calcination technology to capture U(VI). The U(VI) removal capacity by MHAPA even arrived 2685.6 mg g

In previous reports, carbon dots (CDs) were customarily used as fluorescent probes to detect heavy metal ions. However, scientists neglected to take advantage of the excellent UV absorption properties of CDs to detect heavy metal ions. Herein, we synthesized nitrogen-containing carbon polymer dots (N-CPDs) for the determination of Co

Purpose: To investigate the protective effect of simvastatin (SA) against onset of cerebral aneurysmmediated inflammatory cytokine release and subsequent inflammation and degradation of the extracellular matrix of smooth muscle cells.Methods: Cerebral aneurysm was induced in male Wistar rats using elastase injection, and aneurysm growth was monitored for one month following SA treatment. Inhibition of aneurysm growth was determined along with the expression levels of chemokines and pro-inflammatory cytokines, including TNF-α, IL-8, IL-1β, IL-17, IL-6, macrophage chemoattractant protein-1 (MCP-1), and matrix metalloproteinases 2 and 9, using enzyme-linked immunosorbent assay (ELISA) and reverse transcription polymerase chain reaction (RT-PCR).Results: Aneurysm size decreased in rats treated with SA, relative to values obtained for control rats (p < 0.05). The corresponding expressions of inflammatory cytokines and chemokines were also reduced following pre-treatment with SA (p < 0.05). The results indicate a reduction in the aneurysm area in rats pre-treated with SA, when compared to the untreated animals (p < 0.05).Conclusion: SA treatment inhibits the progression of cerebral aneurysms via its protective effect against inflammation, indicating its potential for use in the prevention and treatment of cerebralaneurysms.

Adenosine-to-inosine (A-to-I) RNA editing is a widespread posttranscriptional modification that has been shown to play an important role in tumorigenesis. Here, we evaluated a total of 19,316 RNA editing sites in the tissues of 80 lung adenocarcinoma (LUAD) patients from our Nanjing Lung Cancer Cohort (NJLCC) and 486 LUAD patients from the TCGA database. The global RNA editing level was significantly increased in tumor tissues and was highly heterogeneous across patients. The high RNA editing level in tumors was attributed to both RNA (ADAR1 expression) and DNA alterations (mutation load). Consensus clustering on RNA editing sites revealed a new molecular subtype (EC3) that was associated with the poorest prognosis of LUAD patients. Importantly, the new classification was independent of classic molecular subtypes based on gene expression or DNA methylation. We further proposed a simplified model including eight RNA editing sites to accurately distinguish the EC3 subtype in our patients. The model was further validated in the TCGA dataset and had an area under the curve (AUC) of the receiver operating characteristic curve of 0.93 (95%CI: 0.91-0.95). In addition, we found that LUAD cell lines with the EC3 subtype were sensitive to four chemotherapy drugs. These findings highlighted the importance of RNA editing events in the tumorigenesis of LUAD and provided insight into the application of RNA editing in the molecular subtyping and clinical treatment of cancer.

Introduction The experiment was undertaken to estimate the effect of BMSC seeding in different scaffold incorporation with HBO on the repair of a seawater-immersed bone defect. And future compared n-HA/PLGA with β-TCP/PLGA as a scaffold in treatment effect of the seawater-immersed bone defect. Methods Sixty New Zealand White rabbits with standard seawater defect in radius were randomly divided into group A (implant with nothing), group B (implanted with autogenous bone), group C (implanted with n-HA/PLGA/BMSCs), and group D (implanted with β-TCP/PLGA/BMSCs). After the implant, each rabbit receives HBO treatment at 2.4 ATA 100% oxygen for 120 min/day for 2 weeks. Radiograph, histological, and biomechanical examinations were used to analyze osteogenesis. Result X-ray analysis shows that n-HA/PLGA/BMSCs and β-TCP/PLGA/BMSCs could accelerate the new bone formation, and the new bone formation in group C was larger than that in group D or group A and close to group B (P < 0.05). After 12 weeks, in group A, the defect without scaffold shows a loose connect tissue filled in the areas. The medullary canal in group B was recanalized. Defects in groups C and D show a larger number of woven bone formation. The new woven bone formation in defect areas in group C was larger than that in group D. The mechanical examination revealed ultimate strength at 12 weeks was group D > group C > group B > group A (P < 0.05). Conclusion Scaffolds of n-HA/PLGA and β-TCP/PLGA incorporation with HBO and BMSCs were effective to treat seawater-immersed bone defect, and n-HA/PLGA was more excellent than β-TCP/PLGA.

Metal–organic framework (MOF)/polymer composites combining advantages of both materials have received significant attention in the recent years. However, the complexity and inefficiency of the curr...

Bupleurum chinense DC-Paeonia lactiflora Pall (BCD-PLP) is a common clinical herb pair in traditional Chinese medicine (TCM) prescriptions commonly used to treat depression. However, its combination mechanisms with its anti-depressive effects remain highly unclear.Here, an effective strategy has been developed to study the combination mechanisms of Bupleurum chinense DC (BCD) and Paeonia lactiflora Pall (PLP) by integrating serum pharmacochemistry analysis, metabolomics technology, and molecular docking technology.First, the depression model rats were replicated by the chronic unpredictable mild stress (CUMS) procedure, and the difference in the chemical composition in vivo before and after the combination of BCD and PLP was analyzed by integrating background subtraction and multivariate statistical analysis techniques. Then, UPLC/HRMS-based serum metabolomics was performed to analyze the synergistic effect on metabolite regulation before and after the combination of BCD and PLP. Further, the correlation analysis between the differential exogenous chemical components and the differential endogenous metabolites before and after the combination was employed to dissect the combination mechanisms from a global perspective of combining metabolomics and serum pharmacochemistry. Finally, the molecular docking between the differential chemical components and the key metabolic enzymes was applied to verify the regulatory effect of the differential exogenous chemical components on the differential endogenous metabolites.The serum pharmacochemistry analysis results demonstrated that the combination of BCD and PLP could significantly affect the content of 10 components in BCD (including 5 prototype components were significantly decreased and 5 metabolites were significantly increased) and 8 components in PLP (including 4 prototype components and 3 metabolites were significantly increased, 1 metabolite was significantly decreased), which indicated that the combination could enhance BCD prototype components' metabolism and the absorption of the PLP prototype components. Besides, metabolomics results indicated that the BCD-PLP herb pair group significantly reversed more metabolites (8) than BCD and PLP single herb group (54) and has a stronger regulatory effect on metabolite disorders caused by CUMS. Furthermore, the correlation analysis results suggested that saikogenin F and saikogenin G were significantly positively correlated with the endogenous metabolite itaconate, an endogenous anti-inflammatory metabolite; and benzoic acid was significantly positively correlated with D-serine, an endogenous metabolite with an antidepressant effect. Finally, the molecular docking results further confirmed that the combination of BCD and PLP could affect the activities of cis-aconitic acid decarboxylase and D-amino acid oxidase by increasing the in vivo concentration of saikogenin F and benzoic acid, which further enhances its anti-inflammatory activity and anti-depressive effect.In this study, an effective strategy has been developed to study the combination mechanisms of BCD and PLP by integrating serum pharmacochemistry analysis, multivariate statistical analysis, metabolomics technology, and molecular docking technology. Based on this strategy, the present study indicated that the combination of BCD and PLP could affect the activities of cis-aconitic acid decarboxylase and D-amino acid oxidase by increasing the concentration of saikogenin F and benzoic acid in vivo, which further enhances its anti-depressive effect. In short, this strategy will provide a reliable method for elucidating the herb-herb compatibility mechanism of TCM.

Previous studies have assumed that the volatility of exogenous shocks is constant, which can only measure the level effects of uncertain shocks. This article introduces the time-varying volatility model into a Dynamic Stochastic General Equilibrium (D.S.G.E.) model and uses the third-order perturbation method to identify and decompose the level and volatility effects of uncertainty shocks. Based on the results of empirical research in China, the effect of volatility shocks is different from that of level shocks: the effect of level shocks is direct and positive, and its impact is larger, while the effect of volatility shocks is indirect and negative, and its impact is smaller. This article also finds that the impact of uncertainty shocks will lead to economic stagnation, inflation, and the stagflation effect.

We investigated autosomal mosaic chromosomal alterations (mCAs) in 10,248 non-small cell lung cancer (NSCLC) cases and 9,298 cancer-free controls of Chinese ancestry. Mosaic loss and copy-neutral loss of heterozygosity were associated with an increased risk of NSCLC, while mosaic gain was associated with a decreased risk of NSCLC, especially those spanning telomeres. The increased cell fraction of mCAs was also correlated with an increasing NSCLC risk in the affected individuals. Both multiplicative and additive interactions were observed between polygenic risk score (PRS) and the presence of mosaic loss, where carriers of mosaic loss events with cell fractions ≥5% among the high genetic risk group had the greatest risk for developing NSCLC. These findings suggest that mCA events may act as a new endogenous indicator for risk of NSCLC and have the potential to be jointly used with PRS to optimize risk stratification of NSCLC.

The current study was conducted to compare the therapeutic effects of proximal femoral nail antirotation (PFNA-II) and artificial total hip arthroplasty (THA) on elderly Chinese patients with unstable intertrochanteric femoral fracture combined with severe osteoporosis. There were 60 people in each group. The duration of surgery, blood loss, and weight-bearing period when standing on the floor were compared between the two groups (P > 0.05). Harries function scores of both groups increased over time. Scores of THA group were significantly higher than those of PFNA-II group during six- and twelve-months follow-up visit (P < 0.05). In addition, excellent and good rates of hip joint function in THA group were higher than those of PFNA-II group during twelve-month follow-up visit (P < 0.05). The occurrence rates of follow-up complications in both groups showed no statistical significance (P > 0.05). Thus, both PFNA-II and THA have good effects on Chinese elderly patients with unstable intertrochanteric femoral fracture combined with severe osteoporosis.

Production of multi-carbon (C2+) products via electrochemical CO2 reduction reaction (CO2RR) has aroused intensive interest in this decade. However, it is still a great challenge in large-scale synthesis of electrocatalysts for C2+ compounds production with high selectivity and rate in neutral electrolyte. In this study, a robust and scalable aqueous synthesis method was proposed to prepare CuO nanosheets, which was directly used as CO2RR electrocatalyst. The catalyst underwent dynamic restructuring during the pre-reduction stage, which significantly changed the morphology, crystalline structure and electrochemical properties of the catalyst. As a result, the pristine CuO nanosheets gradually evolved to coral-like Cu nanoparticle ensembles (CL-Cu NEs). In 0.1 M KHCO3 at −1.1 V vs. RHE, the CL-Cu NEs exhibited a faradaic efficiency and partial current density of C2+ products of 72.1% and 25.2 mA cm−2 respectively and no degradation was observed in 15 h running. In contrast to many Cu-based catalysts showing considerable C2+ products selectivity, the (sub)surface oxygen and Cu+ species were unlikely to play a significant role in this study. The strong performance of CL-Cu NEs was ascribed to the synergism between the coral-like morphology and abundant Cu(1 0 0)/Cu(1 1 1) interfaces. This methodology may provide a cost-effective approach for large-scale preparation of CO2RR electrocatalysts with ideal nanostructure.

A facile enzymatic modular assembly strategy for the preparative-scale synthesis of poly-N-acetyllactosamine (poly-LacNAc) glycans with varied lengths and designed sialylation and/or fucosylation patterns is described. These glycans were printed as a microarray to investigate their interactions with a panel of glycan binding proteins (GBPs). Binding affinities revealed that the avidity of GBPs could be largely affected by the length and the patterns of sialylation and fucosylation.

Rationale: As the transcriptional products of active enhancers, enhancer RNAs (eRNAs) are essential for the initiation of tumorigenesis. However, the landscape and functional characteristics of eRNAs in Chinese lung adenocarcinoma, and the clinical utility of eRNA-based molecular subtypes remain largely unknown. Methods: A genome-wide profiling of eRNAs was performed in 80 Chinese lung adenocarcinoma patients with RNA-seq data. Functional eRNAs and associated genes were identified between paired adenocarcinoma and adjacent samples. Unsupervised clustering of functional eRNAs was conducted and the associations with molecular characteristics and clinical outcomes were accessed by integrating whole-genome sequencing data and clinical data. Additionally, 481 lung adenocarcinoma patients were used for the validation based on The Cancer Genome Atlas (TCGA) dataset. Results: A total of 3297 eRNAs with sufficient expression were identified, which were globally upregulated in adenocarcinoma samples compared to matched-adjacent pairs (P = 7.61×10-3). Further analyses indicated that these upregulated eRNAs were correlated with copy number amplification (CNA) status (Cor = 0.22, P = 0.045), and eRNA-correlated genes were primarily involved in cell cycle and immune system-related pathways. Based on the co-expression analysis of eRNAs with protein-coding genes, we defined 188 functional eRNAs and their correlated genes were overrepresented in cancer driver genes (ER = 1.98, P = 5.95×10-12) and clinically-actionable genes (ER = 2.19, P = 3.44×10-4). The eRNA-based consensus clustering further identified a novel molecular subtype with immune deficiency and a high-level of genomic alterations, which was associated with poor clinical outcomes of lung adenocarcinoma patients (OS: HR = 1.91, P = 0.015; PFI: HR = 1.64, P = 0.034). Conclusions: The genome-wide identification and characterization of eRNAs reveal novel regulators for the development of lung cancer, which provides a new biological dimension for the understanding of eRNAs during lung carcinogenesis and emphasize the clinical utility of eRNA-based molecular subtypes in the treatment of lung adenocarcinoma.

Deep neural networks (DNNs) have profoundly changed our lifeways in recent years. The cost of training a complicated DNN model is always overwhelming for most users with limited computation and storage resources. Consequently, an increasing number of people are considering to resort to a cloud for an outsourced DNN model training. However, the DNN models training process outsourced to the cloud faces privacy and security issues due to the semi-honest and malicious cloud environments. To preserve the privacy of the data and the parameters in DNN models during the outsourced training and to detect whether the models are injected with backdoors, this paper presents DeepGuard, a framework of privacy-preserving backdoor detection and identification in an outsourced cloud environment for multi-participant computation. In particular, we design a privacy-preserving reverse engineering algorithm for recovering the triggers and detecting the backdoor attacks among three cooperative but non-collusion servers. Moreover, we propose a backdoor identification algorithm adapting to single-label and multi-label attack detection. Finally, extensive experiments on the prevailing datasets such as MNIST, SVHN, and GTSRB confirm the effectiveness and efficiency of backdoor detection and identification in a privacy-preserving DNN model.