[Research progress in associations between dental caries and systemic diseases]

Dental caries is a bacteria-mediated, multifactorial, chronic progressive disease that results in the phasic demineralization and remineralization of dental hard tissues. In recent years, amounts of studies have focused on the association between dental caries and systemic diseases. This paper reviews the researches about associations between caries and systemic diseases. An electronic search was conducted in PubMed and Web of Science for articles published from 2003 to 2022 in the English language. Studies were included in the following ten categories of systemic diseases: cardiovascular diseases, metabolic disorders, respiratory diseases, autoimmune rheumatic diseases, neurologic diseases, gastrointestinal diseases, kidney diseases, skin diseases, iron deficiency anaemia and tumors. This review discusses the relationship between dental caries and systemic diseases, as well as the potentially involved mechanisms, providing new ideas for disease prevention, diagnosis, and treatment strategies for dentists and other clinicians.

Clinically Oriented CBCT Periapical Lesion Evaluation via 3D CNN Algorithm

Apical periodontitis (AP) is one of the most prevalent disorders in dentistry. However, it can be underdiagnosed in asymptomatic patients. In addition, the perioperative evaluation of 3-dimensional (3D) lesion volume is of great clinical relevance, but the required slice-by-slice manual delineation method is time- and labor-intensive. Here, for quickly and accurately detecting and segmenting periapical lesions (PALs) associated with AP on cone beam computed tomography (CBCT) images, we proposed and geographically validated a novel 3D deep convolutional neural network algorithm, named PAL-Net. On the internal 5-fold cross-validation set, our PAL-Net achieved an area under the receiver operating characteristic curve (AUC) of 0.98. The algorithm also improved the diagnostic performance of dentists with varying levels of experience, as evidenced by their enhanced average AUC values (junior dentists: 0.89-0.94; senior dentists: 0.91-0.93), and significantly reduced the diagnostic time (junior dentists: 69.3 min faster; senior dentists: 32.4 min faster). Moreover, our PAL-Net achieved an average Dice similarity coefficient over 0.87 (0.85-0.88), which is superior or comparable to that of other existing state-of-the-art PAL segmentation algorithms. Furthermore, we validated the generalizability of the PAL-Net system using multiple external data sets from Central, East, and North China, showing that our PAL-Net has strong robustness. Our PAL-Net can help improve the diagnostic performance and speed of dentists working from CBCT images, provide clinically relevant volume information to dentists, and can potentially be applied in dental clinics, especially without expert-level dentists or radiologists.

SNORA56-mediated pseudouridylation of 28 S rRNA inhibits ferroptosis and promotes colorectal cancer proliferation by enhancing GCLC translation

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignancies and is characterized by reprogrammed metabolism. Ferroptosis, a programmed cell death dependent on iron, has emerged as a promising strategy for CRC treatment. Although small nucleolar RNAs are extensively involved in carcinogenesis, it is unclear if they regulate ferroptosis during CRC pathogenesis.

METHODS

The dysregulated snoRNAs were identified using published sequencing data of CRC tissues. The expression of the candidate snoRNAs, host gene and target gene were assessed by real-time quantitative PCR (RT-qPCR), fluorescence in situ hybridization (FISH), immunohistochemistry (IHC) and western blots. The biological function of critical molecules was investigated using in vitro and in vivo strategies including Cell Counting Kit-8 (CCK8), colony formation assay, flow cytometry, Fe2+/Fe3+, GSH/GSSG and the xenograft mice models. The ribosomal activities were determined by polysome profiling and O-propargyl-puromycin (OP-Puro) assay. The proteomics was conducted to clarify the downstream targets and the underlying mechanisms were validated by IHC, Pearson correlation analysis, protein stability and rescue assays. The clinical significance of the snoRNA was explored using the Cox proportional hazard model, receiver operating characteristic (ROC) and survival analysis.

RESULTS

Here, we investigated the SNORA56, which was elevated in CRC tissues and plasma, and correlated with CRC prognosis. SNORA56 deficiency in CRC impaired proliferation and triggered ferroptosis, resulting in reduced tumorigenesis. Mechanistically, SNORA56 mediated the pseudouridylation of 28 S rRNA at the U1664 site and promoted the translation of the catalytic subunit of glutamate cysteine ligase (GCLC), an indispensable rate-limiting enzyme in the biosynthesis of glutathione, which can inhibit ferroptosis by suppressing lipid peroxidation.

CONCLUSIONS

Therefore, the SNORA56/28S rRNA/GCLC axis stimulates CRC progression by inhibiting the accumulation of cellular peroxides, and it may provide biomarker and therapeutic applications in CRC.

SNORD11B-mediated 2'-O-methylation of primary let-7a in colorectal carcinogenesis

Evidence indicates that small nucleolar RNAs (snoRNAs) participate in tumorigenesis and development and could be promising biomarkers for colorectal cancer (CRC). Here, we examine the profile of snoRNAs in CRC and find that expression of SNORD11B is increased in CRC tumor tissues and cell lines, with a significant positive correlation between SNORD11B expression and that of its host gene NOP58. SNORD11B promotes CRC cell proliferation and invasion and inhibits apoptosis. Mechanistically, SNORD11B promotes the processing and maturation of 18 S ribosomal RNA (rRNA) by mediating 2'-O-methylated (Nm) modification on the G509 site of 18 S rRNA. Intriguingly, SNORD11B mediates Nm modification on the G225 site of MIRLET7A1HG (pri-let-7a) with a canonical motif, resulting in degradation of pri-let-7a, inhibition of DGCR8 binding, reduction in mature tumor suppressor gene let-7a-5p expression, and upregulation of downstream oncogene translation. SNORD11B performs comparably to CEA and CA199 in diagnosing CRC. High expression of SNORD11B is significantly correlated with a more advanced TNM stage and lymph node metastasis, which indicates poor prognosis.

[Recognition on dentin dysplasia type Ⅱ]

Dentin dysplasia type Ⅱ (DD-Ⅱ) is a subtype of hereditary dentin disorders. The dentin sialophosphoprotein (DSPP) gene has been revealed to be the causative gene, whose mutations could affect the normal tooth development process. The lesions involve both deciduous and permanent dentition, mainly manifested as tooth discoloration, attrition and even the subsequent malocclusion. If not treated in time, it will significantly affect the physical and psychological health of patients. The disease is difficult to be diagnosed in clinic accurately as its low incidence and hidden manifestations. The present article aims to discuss the clinical and radiographic characteristics, diagnosis, treatment of DD-Ⅱ, in order to improve the overall understanding on DD-Ⅱ for clinicians.

[Two novel and de novo KMT2D mutations on the same allele cause Kabuki syndrome]

Objective: To screen the candidate genes in a patient with Kabuki syndrome (KS), providing basis for genetic counseling, prenatal screening, prenatal diagnosis and facilitating early treatment. Methods: This study included a 16-year-old female KS patient born of non-consanguineous Chinese parents who presented to Department of Orthognathic & Cleft Lip and Palate Plastic Surgery, School and Hospital of Stomatology, Wuhan University. Genomic DNA was extracted from the peripheral blood of the subjects and analyzed by whole-exome sequencing (WES). Sanger sequencing was performed to validate the mutation in the candidate gene. The conformational and physicochemical changes of the mutant were analyzed by Alphafold2, Antheprot and DOG.2.0.1, respectively. Distribution of KMT2D mutations in patients with KS was analyzed based on the Human Gene Mutation Database Results: The proband manifested a typical KS facial gestalt, congenital cleft palate, fifth finger deformity, hypodontia, renal hypoplasia and hydronephrosis. Two de novo mutations c.[1166A>C; 1167dupC] (NM_003482) in cis on the same allele in the KMT2D gene were identified by WES and confirmed by allele-specific PCR. Bioinformatics analysis showed that three more α-helixes were added, and a (β-) turn and a (β-) sheet were reduced in KMT2D p. Y389S, p.V390Rfs*26 compared with the wild type. Meanwhile, the interceptive mutant-KMT2D protein p.V390Rfs*26 lost all four domains (FYRN domain, FYRC domain, SET domain, and PostSET domain), which may cause functional disabilities. Conclusions: Our study is the first to identify two novel and de novo KMT2D mutations in cis on the same allele in a KS patient and extends the KMT2D mutation spectrum of KS, providing evidence for genetic susceptibility counseling, prenatal screening and diagnosis, and early treatment of KS.

[A semi-supervised network-based tissue-aware contrast enhancement method for CT images]

OBJECTIVE

To propose a tissue- aware contrast enhancement network (T- ACEnet) for CT image enhancement and validate its accuracy in CT image organ segmentation tasks.

METHODS

The original CT images were mapped to generate low dynamic grayscale images with lung and soft tissue window contrasts, and the supervised sub-network learned to recognize the optimal window width and level setting of the lung and abdominal soft tissues via the lung mask. The self-supervised sub-network then used the extreme value suppression loss function to preserve more organ edge structure information. The images generated by the T-ACEnet were fed into the segmentation network to segment multiple abdominal organs.

RESULTS

The images obtained by T-ACEnet were capable of providing more window setting information in a single image, which allowed the physicians to conduct preliminary screening of the lesions. Compared with the suboptimal methods, T-ACE images achieved improvements by 0.51, 0.26, 0.10, and 14.14 in SSIM, QABF, VIFF, and PSNR metrics, respectively, with a reduced MSE by an order of magnitude. When T-ACE images were used as input for segmentation networks, the organ segmentation accuracy could be effectively improved without changing the model as compared with the original CT images. All the 5 segmentation quantitative indices were improved, with the maximum improvement of 4.16%.

CONCLUSION

The T-ACEnet can perceptually improve the contrast of organ tissues and provide more comprehensive and continuous diagnostic information, and the T-ACE images generated using this method can significantly improve the performance of organ segmentation tasks.

[A semi-supervised material quantitative intelligent imaging algorithm for spectral CT based on prior information perception learning]

OBJECTIVE

To propose a semi-supervised material quantitative intelligent imaging algorithm based on prior information perception learning (SLMD-Net) to improve the quality and precision of spectral CT imaging.

METHODS

The algorithm includes a supervised and a self- supervised submodule. In the supervised submodule, the mapping relationship between low and high signal-to-noise ratio (SNR) data was constructed through mean square error loss function learning based on a small labeled dataset. In the self- supervised sub-module, an image recovery model was utilized to construct the loss function incorporating the prior information from a large unlabeled low SNR basic material image dataset, and the total variation (TV) model was used to to characterize the prior information of the images. The two submodules were combined to form the SLMD-Net method, and pre-clinical simulation data were used to validate the feasibility and effectiveness of the algorithm.

RESULTS

Compared with the traditional model-driven quantitative imaging methods (FBP-DI, PWLS-PCG, and E3DTV), data-driven supervised-learning-based quantitative imaging methods (SUMD-Net and BFCNN), a material quantitative imaging method based on unsupervised learning (UNTV-Net) and semi-supervised learning-based cycle consistent generative adversarial network (Semi-CycleGAN), the proposed SLMD-Net method had better performance in both visual and quantitative assessments. For quantitative imaging of water and bone materials, the SLMD-Net method had the highest PSNR index (31.82 and 29.06), the highest FSIM index (0.95 and 0.90), and the lowest RMSE index (0.03 and 0.02), respectively) and achieved significantly higher image quality scores than the other 7 material decomposition methods (P < 0.05). The material quantitative imaging performance of SLMD-Net was close to that of the supervised network SUMD-Net trained with labeled data with a doubled size.

CONCLUSIONS

A small labeled dataset and a large unlabeled low SNR material image dataset can be fully used to suppress noise amplification and artifacts in basic material decomposition in spectral CT and reduce the dependence on labeled data-driven network, which considers more realistic scenario in clinics.

O-GlcNAcylated LARP1 positively regulated by circCLNS1A facilitates hepatoblastoma progression through DKK4/β-catenin signalling

BACKGROUND

Accumulating studies have shown that La-related protein 1 (LARP1) is involved in the occurrence and development of various tumours. However, the expression pattern and biological role of LARP1 in hepatoblastoma (HB) remain unclear so far.

METHODS

LARP1 expression level in HB and adjacent normal liver tissues was analysed by qRT-PCR, Western blotting and immunohistochemistry assays. The prognostic significance of LARP1 was evaluated by Kaplan-Meier method and multivariate Cox regression analysis. In vitro and in vivo functional assays were implemented to clarify the biological effects of LARP1 on HB cells. Mechanistically, the regulatory roles of O-GlcNAcylation and circCLNS1A in LARP1 expression were investigated by co-immunoprecipitation (co-IP), immunofluorescence, RNA immunoprecipitation (RIP), RNA pull-down and protein stability assays. Moreover, RNA-sequencing, co-IP, RIP, mRNA stability and poly(A)-tail length assays were performed to investigate the association between LARP1 and DKK4. The expression and diagnostic significance of plasma DKK4 protein in multi-centre cohorts were evaluated by ELISA and ROC curves.

RESULTS

LARP1 mRNA and protein levels were remarkably elevated in HB tissues and associated with worse prognosis of HB patients. LARP1 knockdown abolished cell proliferation, triggered cell apoptosis in vitro as well as prohibited tumour growth in vivo, whereas LARP1 overexpression incited HB progression. Mechanistically, O-GlcNAcylation of LARP1 Ser672 by O-GlcNAc transferase strengthened its binding to circCLNS1A and then protected LARP1 from TRIM-25-mediated ubiquitination and proteolysis. LARP1 upregulation subsequently led to DKK4 mRNA stabilisation by competitively interacting with PABPC1 to prevent DKK4 mRNA from B-cell translocation gene 2-dependent deadenylation and degradation, thus facilitating β-catenin protein expression and nuclear import.

CONCLUSION

This study indicates that upregulated protein level of O-GlcNAcylated LARP1 mediated by circCLNS1A promotes the tumorigenesis and progression of HB through LARP1/DKK4/β-catenin axis. Hence, LARP1 and DKK4 are promising therapeutical target and diagnostic/prognostic plasma biomarker for HB.

SNORA14A inhibits hepatoblastoma cell proliferation by regulating SDHB-mediated succinate metabolism

Hepatoblastoma (HB) is the most common paediatric liver malignancy. Dysregulation of small nucleolar RNAs (snoRNAs) is a critical inducer of tumour initiation and progression. However, the association between snoRNAs and HB remains unknown. Here, we conducted snoRNA expression profiling in HB by snoRNA sequencing and identified a decreased level of SNORA14A, a box H/ACA snoRNA, in HB tissues. Low expression of SNORA14A was correlated with PRETEXT stage and metastasis in patients. Functionally, overexpression of SNORA14A suppressed HB cell proliferation and triggered cell apoptosis and G2/M phase arrest. Mechanistically, SNORA14A overexpression promoted the processing and maturation of the 18 S ribosomal RNA (rRNA) precursor to increase succinate dehydrogenase subunit B (SDHB) protein levels. In accordance with SNORA14A downregulation, SDHB protein expression was significantly reduced in HB tissues and cells, accompanied by abnormal accumulation of succinate. Overexpression of SDHB showed antiproliferative and proapoptotic effects and the capacity to induce G2/M phase arrest, while succinate dose-dependently stimulated HB cell growth. Furthermore, the inhibition of SNORA14A in HB malignant phenotypes was mediated by SDHB upregulation-induced reduction of cellular succinate levels. Therefore, the SNORA14A/18 S rRNA/SDHB axis suppresses HB progression by preventing cellular accumulation of the oncometabolite succinate and provides promising prognostic biomarkers and novel therapeutic targets for HB.

[Effects of circadian rhythm on the development of dental hard tissues]

Circadian rhythm is regulated by circadian clock, which is formed by the body response to external cyclic stimuli through the endogenous circadian clock. Circadian rhythm disturbance is closely related to the risks of a variety of diseases, and its impact on oral health cannot be ignored. Exploring the relationship and related molecular mechanism between circadian rhythm and dental hard tissues development are helpful to deeply understand the pathogenesis of developmental defects on these tissues, which could provide a theoretical basis for prevention and treatment on disorders of dental hard tissues. In order to provide guidance for the disease prevention and treatment, based on the summarization of current research progress, this paper focuses on the involvement of biorhythm in the development of tooth hard tissues as well as the disturbance of circadian rhythm on the formation of enamel and dentin, and analyzes the related regulating mechanism of circadian rhythm and genes during the development of tooth hard tissues.

[Low-dose helical CT projection data restoration using noise estimation]

OBJECTIVE

To build a helical CT projection data restoration model at random low-dose levels.

METHODS

We used a noise estimation module to achieve noise estimation and obtained a low-dose projection noise variance map, which was used to guide projection data recovery by the projection data restoration module. A filtering back-projection algorithm (FBP) was finally used to reconstruct the images. The 3D wavelet group residual dense network (3DWGRDN) was adopted to build the network architecture of the noise estimation and projection data restoration module using asymmetric loss and total variational regularization. For validation of the model, 1/10 and 1/15 of normal dose helical CT images were restored using the proposed model and 3 other restoration models (IRLNet, REDCNN and MWResNet), and the results were visually and quantitatively compared.

RESULTS

Quantitative comparisons of the restored images showed that the proposed helical CT projection data restoration model increased the structural similarity index by 5.79% to 17.46% compared with the other restoration algorithms (P < 0.05). The image quality scores of the proposed method rated by clinical radiologists ranged from 7.19% to 17.38%, significantly higher than the other restoration algorithms (P < 0.05).

CONCLUSION

The proposed method can effectively suppress noises and reduce artifacts in the projection data at different low-dose levels while preserving the integrity of the edges and fine details of the reconstructed CT images.

[An adaptive CT metal artifact reduction algorithm that combines projection interpolation and physical correction]

OBJECTIVE

To propose an adaptive weighted CT metal artifact reduce algorithm that combines projection interpolation and physical correction.

METHODS

A normalized metal projection interpolation algorithm was used to obtain the initial corrected projection data. A metal physical correction model was then introduced to obtain the physically corrected projection data. To verify the effectiveness of the method, we conducted experiments using simulation data and clinical data. For the simulation data, the quantitative indicators PSNR and SSIM were used for evaluation, while for the clinical data, the resultant images were evaluated by imaging experts to compare the artifact-reducing performance of different methods.

RESULTS

For the simulation data, the proposed method improved the PSNR value by at least 0.2 dB and resulted in the highest SSIM value among the methods for comparison. The experiment with the clinical data showed that the imaging experts gave the highest scores of 3.616±0.338 (in a 5-point scale) to the images processed using the proposed method, which had significant better artifact-reducing performance than the other methods (P < 0.001).

CONCLUSION

The metal artifact reduction algorithm proposed herein can effectively reduce metal artifacts while preserving the tissue structure information and reducing the generation of new artifacts.

[A nonlocal spectral similarity-induced material decomposition method for noise reduction of dual-energy CT images]

OBJECTIVE

To propose a nonlocal spectral similarity-induced material decomposition network (NSSD-Net) to reduce the correlation noise in the low-dose spectral CT decomposed images.

METHODS

We first built a model-driven iterative decomposition model for dual-energy CT, optimized the objective function solving process using the iterative shrinking threshold algorithm (ISTA), and cast the ISTA decomposition model into the deep learning network. We then developed a novel cost function based on the nonlocal spectral similarity to constrain the training process. To validate the decomposition performance, we established a material decomposition dataset by real patient dual-energy CT data. The NSSD-Net was compared with two traditional model-driven material decomposition methods, one data-based material decomposition method and one data-model coupling-driven material decomposition supervised learning method.

RESULTS

The quantitative results showed that compared with the two traditional methods, the NSSD-Net method obtained the highest PNSR values (31.383 and 31.444) and SSIM values (0.970 and 0.963) and the lowest RMSE values (2.901 and 1.633). Compared with the datamodel coupling-driven supervised decomposition method, the NSSD-Net method obtained the highest SSIM values on water and bone decomposed results. The results of subjective image quality assessment by clinical experts showed that the NSSD-Net achieved the highest image quality assessment scores on water and bone basis material (8.625 and 8.250), showing significant differences from the other 4 decomposition methods (P < 0.001).

CONCLUSION

The proposed method can achieve high-precision material decomposition and avoid training data quality issues and model unexplainable issues.

The N6-methyladenosine modification enhances ferroptosis resistance through inhibiting SLC7A11 mRNA deadenylation in hepatoblastoma

Background

Solute carrier family 7 member 11 (SLC7A11) is overexpressed in multiple human tumours and functions as a transporter importing cystine for glutathione biosynthesis. It promotes tumour development in part by suppressing ferroptosis, a newly identified form of cell death that plays a pivotal role in the suppression of tumorigenesis. However, the role and underlying mechanisms of SLC7A11‐mediated ferroptosis in hepatoblastoma (HB) remain largely unknown.

Methods

Reverse transcription quantitative real‐time PCR (RT‐qPCR) and western blotting were used to measure SLC7A11 levels. Cell proliferation, colony formation, lipid reactive oxygen species (ROS), MDA concentration, 4‐HNE, GSH/GSSG ratio and cell death assays as well as subcutaneous xenograft experiments were used to elucidate the effects of SLC7A11 in HB cell proliferation and ferroptosis. Furthermore, MeRIP‐qPCR, dual luciferase reporter, RNA pulldown, RNA immunoprecipitation (RIP) and RACE‐PAT assays were performed to elucidate the underlying mechanism through which SLC7A11 was regulated by the m6A modification in HB.

Results

SLC7A11 expression was highly upregulated in HB. SLC7A11 upregulation promoted HB cell proliferation in vitro and in vivo, inhibiting HB cell ferroptosis. Mechanistically, SLC7A11 mRNA exhibited abnormal METTL3‐mediated m6A modification, which enhanced its stability and expression. IGF2 mRNA‐binding protein 1 (IGF2BP1) was identified as the m6A reader of SLC7A11, enhancing SLC7A11 mRNA stability and expression by inhibiting SLC7A11 mRNA deadenylation in an m6A‐dependent manner. Moreover, IGF2BP1 was found to block BTG2/CCR4‐NOT complex recruitment via competitively binding to PABPC1, thereby suppressing SLC7A11 mRNA deadenylation.

Conclusions

Our findings demonstrated that the METTL3‐mediated SLC7A11 m6A modification enhances HB ferroptosis resistance. The METTL3/IGF2BP1/m6A modification promotes SLC7A11 mRNA stability and upregulates its expression by inhibiting the deadenylation process. Our study highlights a critical role of the m6A modification in SLC7A11‐mediated ferroptosis, providing a potential strategy for HB therapy through blockade of the m6A‐SLC7A11 axis.

[An in vitro model study of computer-guided endodontic microsurgery]

Objective: To assess and compare the accuracies and operating time of endodontic microsurgery performed by operators with different levels of experience in endodontics using computer-guided techniques including dynamic and static navigations in a surgical simulation model. Methods: Six pairs of three dimensional (3D)-printed models of upper and lower jaws were set up on dental manikins. A total of 120 teeth (10 teeth each jaw) were included in the models. Microsurgeries of osteotomy and root-resection were performed on the models by two operators with different experience, namely novices and experts, under of free hand (FH)(n=20), dynamic navigation (DN)(n=20), and static navigation (SN)(n=20) conditions, respectively. The duration of each operation was recorded. Cone-beam CT was taken for 3D-printed models before and after the operation. The path of preoperative surgery planning was simulated. The linear deviations at the entry and the end point and the angular deviation of the access path between the simulated and the actual operation were compared by the software. Results: Significant difference of the entry deviation was observed between the novices and the experts in the FH group [(1.44±0.49) and (1.02±0.58) mm] (q=4.67, P=0.020). There were no significant differences between the novices and the experts in the end point and angular deviations (P>0.05). For the novices, the entry deviations in both DN and SN groups [(0.76±0.32) and (0.66±0.20) mm] were significantly lower than those in FH group (q=7.58, P<0.001; q=8.66, P<0.001). The angular deviations in the abovementioned two groups (5.0°±3.5°, 3.9°±2.1°) were significantly lower than that in FH group (10.9°±6.1°) (q=7.38, P<0.001; q=8.70, P<0.001). For the experts, significant differences were found only in the angular deviations among DN, SN and FH groups (3.6°±1.9°, 3.2°±1.7° and 8.2°±3.9°) (q=5.74, P=0.001; q=6.29, P<0.001). The operation durations were significantly shortened for both the novices [(4.80±2.15), (1.09±0.48) min] (q=14.60, P<0.001; q=20.10, P<0.001) and the experts [(3.40±1.96),(1.02±0.34) min] (q=5.86, P<0.001; q=9.37, P<0.001) by using DN and SN techniques. Regarding the differences between tooth types, in FH group, the operating time on the anterior teeth was significantly shorter than that on the posterior teeth (q=8.14, P<0.001; q=5.20, P=0.007), while in DN and SN groups, there were no significant differences in the operating time between two tooth types (P>0.05). No significant differences were discovered in the accuracies on the anterior and posterior teeth among three techniques or between two kinds of operators (P>0.05). Conclusions: Dynamic and static navigation techniques could assist the clinicians, especially the novices, to improve the accuracies and shorten the operating time of osteotomy and root resection microsurgeries.

[Correlation between chronic diseases and low muscle mass, strength and quality in adults in China]

Objective: To explore the correlation between chronic diseases and muscle mass, strength and quality in adults in China. Methods: Based on the second resurvey of China Kadoorie Biobank (CKB) in 2013-2014, logistic regression models were used to analyze the correlation of different types, number and duration of chronic diseases with low muscle mass, handgrip strength and muscle quality. Results: The prevalence rate of diabetes, coronary heart disease (CHD), stroke and chronic obstructive pulmonary disease (COPD) were 9.6%, 5.8%, 3.2% and 26.8%, respectively, and 38.8% of the participants had at least one disease, and they were more likely to have low handgrip strength and low arm muscle quality (AMQ), and the longer the chronic diseases duration, the higher the risk. The ORs (95%CIs) for low handgrip strength and low AMQ in patients with 1 chronic disease for more than 10 years was 1.64 (1.42-1.90) and 1.83 (1.60-2.10), respectively. The ORs (95%CIs) for low handgrip strength were 1.26 (1.17-1.37), 1.42 (1.23-1.64) and 2.27 (1.55-3.32) and the ORs (95%CIs) for low AMQ were 1.28 (1.18-1.38), 1.67 (1.46-1.92) and 2.41(1.69-3.45), respectively, in patients with 1, 2, ≥3 chronic diseases, the correlation showed a linear trend (P for trend <0.001). Diabetes, CHD and stroke were positively correlated with low handgrip strength and low AMQ. Compared with participants without COPD, COPD patients were more likely to have low appendicular skeletal muscle mass index (ASMI), low total skeletal muscle mass index (TSMI) and low handgrip strength, and the risk was positively correlated with disease duration. Conclusions: Patients with chronic diseases were more likely to have lower muscle strength and muscle quality, especially the patients with multi diseases and longer disease duration. The proportion of low handgrip strength and low AMQ was higher in patients who reported multi-prevalence and longer duration of chronic diseases.

Validity of near-infrared light transillumination for the assessment of proximal caries in permanent teeth

PURPOSE

The aim of this study was to evaluate the performance of DIAGNOcam (DC) in diagnosing proximal caries and to compare its effectiveness with the International Caries Detection and Assessment System (ICDAS) and bitewing radiography (BWR).

METHODS

118 premolars extracted for orthodontic reasons were included and examined using three detection methods and validated by histological sections as the gold standard. The sensitivity, specificity and areas under the ROC curve (Az value) at the outer half enamel (D1), inner half enamel (D2) and dentine (D3) thresholds were compared between different methods.

RESULTS

At all categories, the specificity of DC was almost as high as ICDAS and BWR. DC showed a significantly higher sensitivity (0.68) than both visual (0.33) and radiographic examination (0.47) at the D1 threshold. DC presented the highest Az value (area under the ROC curve) at the D1 and D2 threshold (0.81, 0.86), while BWR showed the greatest Az values at D3 (0.94). Furthermore, DC had the highest association strength with the gold standard (Spearman's ρ = 0.80).

CONCLUSIONS

It can be concluded that DC could detect proximal caries effectively and showed comparable or even better performance than ICDAS and BWR.

Inter-relationships of different electrocardiographic indicators of left ventricular hypertrophy in 25,000 Chinese adults

Background

Several electrocardiographic (ECG) indices have previously been proposed to diagnose left ventricular hypertrophy (LVH). Such indices utilize different criteria, including increased QRS voltage, prolonged QRS duration, left axis deviation, and LAFB and LBBB-like patterns in varying combinations. However, the inter-relationships of these different electrocardiographic indices of LVH with each otherare not fully understood.

The purpose of this study is to estimate the relationships between the different LVH indices.

Methods

Electronic tracings of 12-lead ECGs recorded in 24,786 adult participants in the China Kadoorie Biobank recorded in 2014 were accessed to detect presence of LVH. ECG parameters of LVH, including individual and combinations of such parameters (voltage-only criteria such as Sokolov-Lyon, Cornell, Gubner as well as scores such as Romhilt-Estes point score) were estimated using customized computer software (Cardiolyse Oy, Finland) and compared proprietary LVH point score algorithms (Mortara, USA). Relationships between the different indices were assessed using a correlation matrix to explore associations between individual parameters and combined indices of such parameters. The matrices were used to construct heat maps and identify clustering of individual parameters.

Results

Overall, approximately 10% of the population had LVH assessed by Mortara algorithms. This graph shows that along with the free standing peaks, the rest are divided into two clusters of interconnected individual parameters. In the center of the largest cluster is the parameter, reflecting R-peak magnitude in aVL lead. In the center of another cluster was the left ventricular strain pattern, as described in Romhilt-Estes point score system. Overall, the Sokolov-Lyon index and LVH point score in Veritas algorithm had the strongest relationships with each other, but the Gubner and Cornell indices had relatively weak correlations with the other indices (Table 1). The mean correlation coefficient between five combined LVH indices was as follows: Veritas (Mortara) – 0.58, Sokolov-Lyon – 0.56, Romhilt-Estes – 0.45, Gubner – 0,32, Cornell – 0,3.

Conclusions

Parameters such as R-peak magnitude in aVL and left ventricular strain pattern were the most strongly related with each other. Aggregate indices, such as the Sokolov-Lyon index and LVH point score in Veritas algorithm were the most strongly related with all other indices, but the Gubner and Cornell indices were only weakly correlated. The results reinforce the utility of Sokolov-Lyon index and Mortara algorithms as the optimum measures of LVH.

Funding Acknowledgement

Type of funding sources: None.

[Preliminary results of surgical treatment of fibrous dysplasia of proximal femur in children]

Objective: To investigate the surgical treatment, clinical effect and revision reasons of children with proximal femoral fibrous dysplasia(FD). Methods: The clinical data of 26 children with polyostotic FD of proximal femur who underwent surgery at Department of Pediatric Orthopaedics, Beijing Jishuitan Hospital from June 2016 to June 2018 were retrospectively analyzed. There were 18 males and 8 females with a mean age of 9.2 years (range:5 to 16 years).One of them was McCune Albright syndrome. Fifteen cases were in first operation and 11 cases were in revision operation. The operation methods and results were reviewed,and the causes of revision were analyzed. Results: Among the 15 children who underwent the first operation,13 cases underwent osteotomy or fracture reduction and interlocking intramedullary nail(IMN) fixation;One case underwent valgus osteotomy and pediatric hip plate(PHP)internal fixation;One case underwent valgus osteotomy+lesion curettage+allogeneic bone graft+PHP fixation. Among the 11 children who underwent revision surgery,9 cases were treated with IMN fixation,1 case with PHP fixation,and 1 case with PHP fixation+allogeneic bone graft. The causes of revision included distal fixation failed in 6 cases,proximal fixation failed in 3 cases,plate fixation failed in 5 cases,and recurrence occurred after curettage and artificial bone graft in 2 cases. Patients were followed up for 1.4 years(range:1.0 to 3.5 years) after recent operation. The osteotomy or fracture healed well with good deformity correction. Postoperative complications included infection in 1 case and local bone partial resorption in 1 case. Conclusions: Osteotomy combined with rigid internal fixation is an effective surgical treatment for fibrous dysplasia of proximal femur in children. Internal fixation should cover the whole length of lesion. Intramedullary nail is the most common choice. Because the growth of height and the progress of the disease itself,this deformity is prone to recur in children,needing closely follow-up after operation.

[Prevalence of heart failure and its association with smoking behavior in adults from 10 regions of China]

Objective: To describe the prevalence of heart failure in China and to explore the prospective association between smoking behavior and the risk of incident heart failure. Methods: The subjects were from the China Kadoorie Biobank (CKB) and the baseline survey was conducted from June 2004 to July 2008. A total of 487 197 subjects were included in this study, after excluding those with missing BMI information, lost follow-up immediately after baseline investigation, and self-reported coronary heart disease, stroke, or malignant tumor at baseline. This study included data from baseline and follow-up until December 31, 2016. Cox proportional hazards regression models were used to estimate the association between smoking behavior and the risk of heart failure. Results: The median follow-up time was 10.15 years, during which a total of 4 208 new cases of heart failure occurred, with a crude incidence rate of 0.87/1 000 person-years and a cumulative incidence rate of 0.86%. The higher the age at baseline, the higher the incidence of heart failure. The incidence of heart failure in high age group, rural area and male was higher than that in low age group, urban area and female population respectively. Compared with non-smokers, there was no significant difference in the risk of heart failure in occasional smokers (HR=1.05; 95%CI: 0.91-1.22), while former smokers (HR=1.48; 95%CI:1.31-1.67) and current smokers (HR=1.34;95%CI:1.22-1.49) increased risk. Former smokers (HR=1.33;95%CI:1.21-1.46) and current smokers (HR=1.46; 95%CI:1.31-1.64) had higher risk of heart failure than non-smokers or occasional smokers. No dose-response relationship was observed between the number of cigarettes smoked per day and the risk of heart failure in current and former smokers (for trend P=0.347 and 0.066). Compared with non-smokers or occasional smokers, the hazard ratios of <5, 5-, 10- and ≥20 years since quit smoking were 1.61 (95%CI: 1.36-1.92), 1.55 (95%CI: 1.27-1.90), 1.24 (95%CI: 1.02-1.51) and 1.35 (95%CI: 1.08-1.68), respectively (for trend P=0.091). The hazard ratios of quitting smoking due to disease and other reasons were 1.62 (95%CI:1.41-1.86) and 1.23 (95%CI: 1.04-1.45). Healthy smoking behaviors had a significant protective effect on heart failure compared with non-healthy smoking behaviors (HR=0.75, 95%CI:0.69-0.81). Area and family history of coronary heart disease, and the smoking behaviors interacted with the risk of heart failure (for all interactions were P<0.05). Conclusions: The incidence of heart failure in China is higher in males than females, higher in rural areas than in urban areas, and increases with age. Both former smokers and current smokers had a higher risk of heart failure than nonsmokers or occasional smokers, regardless of the frequency, amount, duration, and reason for quitting. Smoking is an important risk factor for heart failure and comprehensive anti-smoking measures should be maintained.

[Prevalence, patterns and long-term changes of multimorbidity in adults from 10 regions of China]

Objective: To describe the prevalence of multimorbidity and its secular trend, and to explore the common patterns of multimorbidity in Chinese adults. Methods: A total of 25 033 participants who attended the second resurvey of China Kadoorie Biobank (CKB) were included in the study. We used data collected both at baseline (2004-2008) and at resurvey (2013-2014). A total of 13 chronic conditions were included, defined by self-reported, physical examination, and blood sample testing. Multimorbidity was defined as co-existence of two or more chronic conditions. Patterns of multimorbidity were explored using hierarchical cluster analysis. Results: The mean age of participants was (51.5±10.1) years at baseline and (59.5±10.2) years at second resurvey. The prevalence of multimorbidity increased from 33.5% to 58.1% over (8.0±0.8) years of follow-up. The average number of chronic conditions per person increased from 1.15 to 1.82 and all participants increased 0.42 conditions per 5 years on average. Participants who were older, less educated or lived in urban areas had a higher prevalence of multimorbidity and a higher increase in the number of chronic conditions. The increase in the number of chronic conditions was also higher among smokers and heavy alcohol drinkers. The most common multimorbidity pattern in the present population consisted of obesity, hypertension, diabetes, stroke, and heart disease. Conclusions: The prevalence of multimorbidity in Chinese adults is increasing rapidly due to ageing population. Populations of different sociodemographic background and lifestyle habits may have different prevalence of multimorbidity and changes in rates over time.

[Descriptive analysis of fracture hospitalization rate in adults from 10 regions of China]

Objective: To analyze the epidemiological distributions of fracture hospitalization. Methods: The present study included participants who participated in the baseline survey of China Kadoorie Biobank (CKB) and excluded participants who were lost to follow up or died before 2009, leaving a total of 506 004 participants. Negative binomial regression models were used to analyze the epidemiological distribution of any fracture and fracture at five specific body sites (upperlimb, lowerlimb, spine, pelvis and hip) from 2009 to 2016 in 10 regions. Results: During a median follow-up of (7.7±1.2) years (total person-years 3 899 814), we documented 17 118 cases of fracture hospitalizations. The crude fracture hospitalization rate was 4.39/1 000 person-years. After controlling for the increasing age of the fixed cohort, the hospitalization rates of fractures at various body sites increased from 2009 to 2016, with an annual growth rate (95%CI) of 9.1% (8.3%-9.9%) for any fracture. The fracture hospitalization rate was higher in rural than in urban areas except for hip fractures (P<0.05) and the hospitalization rate of any fracture were 5.42/1 000 and 3.24/1 000 person-years in rural and urban areas, respectively. Fracture hospitalization rate increased by age. In participants aged <50 years, men had higher fracture hospitalization rates than women except for pelvis fracture, while in those aged ≥50 years, women had higher fracture hospitalization rates than men. Conclusions: Fracture hospitalization rates increased by age and also showed upward selular trends. As China has begun the aging process, fractures impose a heavier burden on society. It is of great significance to prevent osteoporosis-related and injury-related fractures in order to reduce fractures incidence.

[The correlation of dietary patterns with low muscle mass, strength and quality in adults from 10 regions of China]

Objective: To evaluate the correlation of dietary patterns with low muscle mass, strength and quality in Chinese adults. Methods: Based on the second resurvey of China Kadoorie Biobank, factor analysis was conducted to derive dietary patterns from 20 food groups. Low muscle mass, strength, and quality were defined as the sex-specific lowest quintile of appendicular skeletal muscle mass index (ASMI), total skeletal muscle mass index (TSMI), handgrip strength and arm muscle quality (AMQ) according to Asian Working Group for Sarcopenia recommendations. Logistic regression models were used to evaluate the correlation of dietary patterns with low muscle mass, strength, and quality. Results: Two major dietary patterns were extracted. The balanced dietary pattern was characterized by the intake of a variety of foods, whereas the rice-meat dietary pattern was characterized by high intakes of rice, meat, poultry and fish. Individuals who had the highest quintile score of the balanced dietary pattern were less likely to have low TSMI, handgrip strength or AMQ(OR=0.83, 95%CI: 0.74-0.95 for low TSMI; OR=0.64, 95%CI: 0.56-0.74 for low handgrip strength; OR=0.82, 95%CI: 0.72-0.93 for low AMQ; for trend P<0.05). And those who scored higher on the rice-meat dietary pattern had lower risk of low muscle mass and strength (OR=0.67, 95%CI: 0.55-0.82 for low ASMI; OR=0.69, 95%CI: 0.56-0.85 for low TSMI; OR=0.74, 95%CI: 0.60-0.91 for low handgrip strength; for trend P<0.05). Conclusion: Individuals followed the balanced dietary pattern, as well as those who followed the rice-meat dietary pattern, had better levels of skeletal muscle mass, strength and quality.

[Self-rated health measures and their relations to all-cause and cardiovascular mortality in adults from 10 regions of China]

Objective: To examine the association between self-rated health status (SRH) and all-cause and cardiovascular mortality. Methods: A total of 512 713 adults aged 30-79 years from 10 areas of China were followed from baseline (2004-2008) until 31 December 2016 in the China Kadoorie Biobank study. Global and age-comparative SRH [general self-rated health status (GSRH) and age-comparative self-rated health status (ASRH), respectively] were asked in baseline questionnaires. Causes for mortality were monitored through linkage with established Disease Surveillance Point system and health insurance records. Multivariable Cox proportional regression models were used to estimate the HRs and 95%CIs for the association between SRH measures and all-cause or cardiovascular mortality. Results: During an average of 9.9 years' follow-up, 44 065 deaths were recorded, among which 17 648 were from cardiovascular disease. Compared with excellent GSRH, the HR(95%CI) for all-cause and cardiovascular mortality associated with poor GSRH was 1.84(1.78-1.91) and 1.94(1.82-2.06), respectively. Relative to better ASRH, the HR(95%CI) for all-cause and cardiovascular mortality associated with worse ASRH was 1.75(1.70-1.81) and 1.83(1.73-1.92), respectively. Conclusion: In this large prospective cohort study in China, participants reporting poor GSRH or worse ASRH had significantly higher risk of all-cause and cardiovascular mortality.

Depressive symptoms in Chinese adults with risk factors for diabetes: the Shanghai High-Risk Diabetic Screen (SHiDS) study

AIMS

To evaluate the relationship between newly diagnosed diabetes or prediabetes and depressive symptoms among individuals with risk factors for diabetes in China. We also investigated the associations of depressive symptoms with pancreatic β-cell function and insulin resistance.

METHODS

We used cross-sectional data from the Shanghai High-Risk Diabetic Screen (SHiDS) project. Between 2014 and 2017, a total of 1728 participants were enrolled in this study and underwent an oral glucose tolerance test to screen for diabetes and prediabetes. Insulin resistance was evaluated using the homeostatic model assessment of insulin resistance and the modified Matsuda index. Pancreatic β-cell function was calculated using the homeostatic model assessment of β-cell function, Stumvoll first- and second-phase indexes. Elevated depressive symptoms were determined using the Patient Health Questionnaire-9 (PHQ-9 score ≥ 10).

RESULTS

The prevalence of elevated depressive symptoms in the total study population was 4.8% (83 of 1728). Compared with the normal glucose tolerance group, individuals with newly diagnosed diabetes were less likely to have elevated depressive symptoms even after controlling for potential confounders [adjusted odds ratio (OR) 0.35, 95% confidence interval (CI) 0.18-0.68; P = 0.002]. However, prediabetes was not associated with depressive symptoms. The odds for elevated depressive symptoms were increased in individuals with higher levels of the Stumvoll first-phase index. No association was observed between depressive symptoms and insulin resistance.

CONCLUSION

Elevated depressive symptoms were less prevalent in Chinese individuals with newly diagnosed diabetes among a high-risk population for diabetes.

Independent relevance of left ventricular hypertrophy for risk of ischaemic heart disease in 25,000 Chinese adults

Background

The prevalence of left ventricular hypertrophy (LVH) is strongly related with established cardiovascular disease (CVD) risk factors and, hence, there has been some uncertainty about its independent relevance for ischaemic heart disease (IHD) after taking account of such risk factors.

Purpose

To examine the associations of LVH with prevalent and incident cases of IHD after adjustment for established risk factors for CVD in a population-based study of Chinese adults.

Methods

The prospective China Kadoorie Biobank cohort study was conducted in the general population of 5 urban and 5 rural areas in China, with a baseline survey in 2004–2008. A random sample of 24,786 participants had a 12-lead electrocardiogram (ECG) recorded at the second resurvey in 2013–2014. Electronic records of ECG tracings were used to estimate LVH using 5 different criteria (Sokolov, Cornell, Romhilt-Estes, Gubner and Mortara). IHD cases were recorded by linkage to electronic records of hospitalisation, death and disease registries. Cox regression was used to estimate the associations of LVH with prevalent (n=1325) and incident (n=900) cases of IHD after adjustment for age, sex, region, prior vascular disease, smoking, alcohol, SBP, diabetes, lipids and body mass index (BMI).

Results

The overall prevalence of LVH in the population varied depending on the criteria used for detection (Mortara [10%], Sokolov [14%], Cornell [6%], Romhilt-Estes [4%] and Gubner [1%]). The prevalence of LVH (using Sokolov) increased with age and was higher in men than women (20% vs 10%) and linearly with levels of SBP, but also by ∼10-fold between the 10 regions in China. Irrespective of which criteria were used for detection (Table), LVH was strongly associated with both prevalent and incident cases of IHD after adjustment for age, sex, region and established CVD risk factors. Any one measure of LVH was associated with an adjusted OR (95% CI) of 1.30 (1.10, 1.53) for prevalent IHD and 1.40 (1.20, 1.64) for incident IHD, respectively.

Conclusions

Overall, 1 in 10 Chinese adults had LVH, and LVH was associated with 30% higher risk of prevalent IHD and 40% higher risk of IHD independent of established CVD risk factors.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): UK Wellcome Trust

[Regional and demographic differences on passive smoking among non-smokers aged 30-79 years in 10 regions of China]

Objective: To describe the regional and demographic differences on passive non-smokers from 10 regions involved in the China Kadoorie Biobank (CKB) study. Methods: Detailed information regarding passive smoking behaviors related to 317 486 non-smokers who were 30-79 years old from the 10 study regions were gathered and analyzed. Results: Following the standardization of the 2010 China national population, the prevalence rate of passive smoking was 56.7%, and the prevalence rate of living with smokers was 66.5% among the Chinese adults. Both of the aforementioned rates were higher in rural than in urban areas. Meanwhile, the regional distribution of weekly passive smoking frequency and cumulative duration of passive smoking per week and cumulative duration of passive smoking per day were significantly different. The cumulative passive smoking duration per week increased along with the weekly frequency in people living in urban areas. Among women, the weekly passive smoking frequency was the highest, and the cumulative durations per week and per day appeared the lowest in Hunan, opposite to the situation in Henan. The prevalence of passive smoking among participants living with smokers was 2.27 times (95%CI: 2.24-2.29) of those who were not and the association appeared stronger in women (OR=2.61, 95%CI: 2.58-2.64) but not in men (OR=1.01, 95%CI: 0.95-1.06). Almost all the indicators seemed higher in women than those in men, except for the cumulative duration per day. Furthermore, these indicators appeared higher among those who were at younger age or with less education. The prevalence rates of passive smoking and living with smokers were lower but the cumulative duration per day was higher among those with lower household income. And the two rates were higher in married women and lower in married men, as compared to their counterparts. Conclusion: Regional and demographic differences in passive smoking were noticed among study population of CKB in the 10 regions.

Epidemiological Investigation of OHCWs with COVID-19

During the coronavirus disease 2019 (COVID-19) pandemic, there is an important risk of infection in health care workers, including oral health care workers (OHCWs), due to the characteristics of dental practice. In this retrospective study, data pertaining to the 31 OHCWs diagnosed with COVID-19 in Wuhan, Hubei Province, were retrieved and analyzed. Questionnaires were administered to the subjects over the Internet and telephone. Clinical and epidemiological characteristics and information on the use of personal protective equipment (PPE) were collected. There were 22 females and 9 males, with a median age of 39 y. Although the severity of most cases of COVID-19 (93.5%) was mild or moderate, 1 case was severe, and another case was critical, resulting in death. Fever was the main first symptom of COVID-19, followed by fatigue and myalgia. Most of the OHCWs routinely used PPE such as medical masks, gloves, caps, and work clothes while performing clinical work. N95 or KN95 masks were rarely available because of the scarcity of PPE during the outbreak. Nineteen OHCWs reported a contact history, among whom 7 worked in a fever clinic, 5 reported contact with dental patients suspected of having COVID-19, and 7 reported contact with family members with COVID-19–related symptoms at least 1 d earlier. Our findings indicated that there were few clusters of COVID-19 in dental settings. Since the outbreak, the Hospital of Stomatology, Wuhan University, has provided emergency dental treatment, and none of their staff were infected while providing dental service, which indicates that comprehensive measures such as the use of advanced PPE and environmental disinfection can prevent cross-infection in dental practice. The analysis of the procedures followed during the emergency treatments indicated that OHCWs preferred to recommend conservative treatment to patients, suggesting that attention should be paid to the psychological impact of COVID-19 on dental practitioners.

Genome-wide Analyses Identify a Novel Risk Locus for Nonsyndromic Cleft Palate

The 3 major subphenotypes observed in patients with nonsyndromic orofacial clefts (NSOFCs) are nonsyndromic cleft lip only (NSCLO), nonsyndromic cleft lip with palate (NSCLP), and nonsyndromic cleft palate only (NSCPO). However, the genetic architecture underlying NSCPO is largely unknown. Here we performed a 2-stage genome-wide association study (GWAS) on NSCPO and replication analyses of selected variants in other NSOFCs from the Chinese Han population. We identified a novel locus (15q24.3) and a known locus (1q32.2) where variants in or near the gene reached genome-wide significance (2.80 × 10^-13 < P < 1.72 × 10^-08) in a test for association with NSCPO in a case-control design. Although a variant from 15q24.3 was found to be significantly associated with both NSCPO and NSCLP, the direction of estimated effects on risk were opposite. Our functional annotation of the risk alleles within 15q24.3 coupled with previously established roles of the candidate genes within identified risk loci in periderm development, embryonic patterning, and/or regulation of cellular processes supports their involvement in palate development and the pathogenesis of cleft palate. Our study advances the understanding of the genetic basis of NSOFCs and provides novel insights into the pathogenesis of NSCPO.

[Association between family history of diabetes and incident diabetes of adults: a prospective study]

Objective: To evaluate the association betweew family history of diabetes and incident diabetes of adults. Methods: A total of 49 266 participants in the China Kadoorie Biobank (CKB) study from Wuzhong district of Suzhou city were included in the analysis, after the exclusion of those with heart disease, stroke, cancer and diabetes at baseline survey. The person-year of follow-up was calculated from the date on completion of baseline survey to the date on any firstly-occurred event, i.e., diabetes incidence, death, loss of follow-up, or December 31, 2013. Cox regression model was used to estimate the hazards ratios of the association between family history of diabetes and incident diabetes. Results: During 348 677 person-years of the follow-up (median 7.08 years), a total of 423 men and 791 women were diagnosed as having diabetes. Compared to those without diabetic family history, participants with family history of diabetes showed a higher risk of diabetes, with a HR (95%CI) of 1.90 (1.57-2.29), and the risk increased with the number of relatives suffering from diabetes (Pfor trend<0.05). The family history of maternal type, sibling type, and sibling and parental type had a statistically significant association with the risk of diabetes. The adjusted HR (95%CI) was 2.03 (1.45-2.77), 2.07 (1.56-2.68) and 2.39 (1.14-4.34), respectively. Modification effects of tobacco smoking, alcohol drinking, body mass index and physical activity on the association between diabetic family history and risk of diabetes were not observed in the study (Pfor interaction >0.05). Conclusions: Diabetic family history is associated with the increased incident diabetes, and the risk increased with the number of relatives suffering from diabetes.

[Association between height loss and calcaneus bone mineral density in Chinese adults]

Objective: To examine the association between height loss and calcaneus bone mineral density (BMD) through data gathered from the China Kadoorie Biobank (CKB). Methods: The present study included 24 231 participants who attended the CKB resurvey during 2013-2014, in which calcaneus BMD was measured by quantitative ultrasound method for the first time. Height loss was calculated according to the differences appeared in height measurement between baseline and resurvey. We used linear regression models to estimate the association between height loss and BMD measures. Results: The mean interval between baseline and resurvey was (8.0±0.8 ) years. 33.0% of the participants showed a height loss of ≥1.0 cm, and another 3.7% were with height loss of ≥3.0 cm. After adjustment for potential confounders, there was a linear correlation seen between height loss and BMD (P for all linear trend were <0.001). The βs (95%CIs) for each 1.0 cm of height loss were -0.79 (-0.95--0.63) for broadband ultrasound attenuation (BUA), -2.74 (-3.35--2.13) for speed of sound (SOS), and -1.29 (-1.54--1.04) for stiffness index (SI). Compared with participants with stable height, the multivariate-adjusted βs (95%CIs) for those with height loss of ≥3.0 cm were -3.29 (-4.08--2.50) for BUA, -10.70 (-13.66--7.73) for SOS, and -5.16 (-6.36--3.96) for SI, respectively. According to the subgroup analyses, the association of height loss with BMD measures seemed to be more apparent among females, in those aged ≥55 years, and those being less physically active. Conclusions: BMD became lower with the increase of height loss. Regular height measurement may contribute to the early diagnosis and prevention of osteoporosis.

Parenthood and risk of hip fracture: a 10-year follow-up prospective study of middle-aged women and men in China

This prospective study of Chinese adults demonstrated an inverse J-shaped association of number of children with risk of hip fracture in both men and postmenopausal women aged 50 years or older. Women with 2 or 3 children and men with 4 children had the lowest risk of hip fracture.

INTRODUCTION

Women have higher absolute risks of fracture than men, which is believed to reflect differences in oestrogen exposure. The aim of this study was to compare the associations of number of children with risk of hip fracture between men and women aged over 50 years.

METHODS

The China Kadoorie Biobank (CKB) recruited 133,399 women and 110,296 men, aged 50 years or older between 2004 and 2008. During 10-year follow-up, 2068 participants (1394 women and 674 men) suffered a hip fracture. Cox regression analysis was used to estimate sex-specific adjusted hazard ratios (HRs) and 95% CI for incident hip fracture.

RESULTS

Over 98% of both subsets of men and women aged 50 or older reported having children. Women who had 2 or 3 children had the lowest risks of hip fracture compared with other groups. Compared with nulliparous women, the adjusted HR for hip fracture were 0.89 (95% CI; 0.72, 1.10) for 1 child, 0.79 (0.70, 0.90) for 2 children, 0.79 (0.72, 0.87) for 3 children, 0.81 (0.72, 0.91) for 4 children, and 0.95 (0.83, 1.10) for those with 5 or more children. The associations of number of children with hip fracture were broadly consistent in men of a similar age.

CONCLUSIONS

The concordant effects of the number of children with risk of hip fracture between men and women suggest that the lower risks in multiparous women are not due to differences in oestrogen exposure or other biological effects, but may reflect residual confounding by socioeconomic or lifestyle factors.

Publisher Correction: Parenthood and risk of hip fracture: a 10-year follow-up prospective study of middle-aged women and men in China

The original version of this article, published on 25 November 2019, unfortunately contained a mistake.

Coronavirus Disease 2019 (COVID-19): Emerging and Future Challenges for Dental and Oral Medicine

The epidemic of coronavirus disease 2019 (COVID-19), originating in Wuhan, China, has become a major public health challenge for not only China but also countries around the world. The World Health Organization announced that the outbreaks of the novel coronavirus have constituted a public health emergency of international concern. As of February 26, 2020, COVID-19 has been recognized in 34 countries, with a total of 80,239 laboratory-confirmed cases and 2,700 deaths. Infection control measures are necessary to prevent the virus from further spreading and to help control the epidemic situation. Due to the characteristics of dental settings, the risk of cross infection can be high between patients and dental practitioners. For dental practices and hospitals in areas that are (potentially) affected with COVID-19, strict and effective infection control protocols are urgently needed. This article, based on our experience and relevant guidelines and research, introduces essential knowledge about COVID-19 and nosocomial infection in dental settings and provides recommended management protocols for dental practitioners and students in (potentially) affected areas.

[The cut-off points of body mass index and waist circumference for predicting metabolic risk factors in Chinese adults]

Objective: To assess the association of BMI and waist circumference (WC) with metabolic risk factors, and confirm the appropriate cut-off points of BMI and WC among Chinese adults. Methods: After excluding participants with missing or extreme measurement values, as well as individuals with self-reported histories of cancer, a total of 501 201 adults in baseline and 19 201 adults in the second re-survey from the China Kadoorie Biobank were included. The associations of BMI and WC with metabolic risk factors were estimated. Receiver operating characteristic (ROC) analyses were conducted to assess the appropriate cut-off values of BMI and WC to predict the risk of hypertension, diabetes, dyslipidemia and clustering of risk factors. Results: The prevalence of hypertension, diabetes, dyslipidemia and clustering of risk factors all presented ascending trends with the increasing levels of BMI or WC. Defined as the points on the ROC curve where Youden's index reached the highest, the appropriate overweight cut-off points of BMI were around 24.0 kg/m(2) both in men and women, and the points of WC were around 85 cm in men and 80 to 85 cm in women. With specificity 90% for identification of risk factors, the appropriate obese cut-off points of BMI were around 28.0 kg/m(2) both in men and women, with the range of 27.0 to 28.9 kg/m(2). Conclusions: The cut-off points for overweight and obesity recommended by Coorperative Meta-analysis Group of China Obesity Task Force was verified in the large sample survey conducted more recently. The cut-off points of BMI were 24.0 and 28.0 kg/m(2) for overweight and obesity, and the cut-off point of WC was 85 cm in men and 80 to 85 cm in women for central obesity.

[Association of body mass index and waist circumference with major chronic diseases in Chinese adults]

Objective: To examine the association of BMI with major chronic diseases morbidity and all-cause mortality in Chinese adults. Methods: This study is based on China Kadoorie Biobank. Anthropometric indexes were objectively measured at the baseline survey during 2004-2008. After excluding participants with heart disease, stroke, cancer, COPD and diabetes, 428 113 participants aged 30 to 79 years were included in the analysis. Cox regression models were used to investigate the associations of BMI and waist circumference with incidence of major chronic diseases (including cardiovascular disease, cancer, COPD, and type 2 diabetes) and all-cause mortality. Results: Over an average of 10 years, 131 454 participants developed any one of major chronic diseases. A total of 26 892 all-cause deaths were reported. The risk of major chronic diseases increased with BMI. Compared with normal BMI (18.5-24.0 kg/m(2)), the HR (95%CI) of overweight (BMI 24.0-28.0 kg/m(2)) and obesity (BMI≥28.0 kg/m(2)) were 1.26 (95%CI: 1.24-1.27) and 1.59 (95%CI: 1.57-1.62) respectively. Underweight and obesity were both associated with risk of all-cause mortality. Waist circumference was positively associated with risk of major chronic diseases and all-cause mortality. According to recommended cut-off points of BMI and waist circumference for Chinese adults, maintaining a healthy body weight would prevent 12% incident cases of major chronic diseases. Conclusion: General and central obesity were risk factors for major chronic disease among Chinese adults.

[Frequency of bowel movements and risk of Parkinson's disease: a prospective cohort study in adults in China]

Objective: To evaluate the association between the frequency of bowel movement (BMF) and the risk of Parkinson's disease (PD). Methods: In this study, 510 134 participants from the China Kadoorie Biobank (CKB) were included after excluding those who reported to had been diagnosed with cancer at baseline survey. The baseline survey was conducted from 2004 to 2008. The study used the data from the baseline survey and follow-up until December 31, 2016. Cox proportional hazards regression models were used to estimate the HRs and the 95%CIs of risk of PD diagnosis with BMF. Results: During an average follow-up period of (9.9±1.9) years, 808 participants were diagnosed with PD. Compared with participants who had bowel movements every day, the multivariable-adjusted HR (95%CI) for those who had bowel movements<3 times/week, once every 2-3 days, and>1 time/day were 3.62 (2.88-4.54), 2.13 (1.74-2.60), and 0.81 (0.63-1.05), respectively. The linear trend test results of the association between BMF and risk of PD diagnosis was significant (P<0.001). Compared with the participants who had bowel movements ≥1 time/day, the multivariable-adjusted HR (95%CI) for those who had bowel movements<1 time/day was 3.13 (2.32-4.23) within the 5 years of follow- up and was 2.48 (2.05-3.01) beyond the 5 years of follow-up. The gender specific results were similar. The association of BMF<1 time/day with risk of PD diagnosis was stronger in older participants. Conclusions: The participants with low BMF at baseline survey would have higher risk for PD diagnosis in the subsequent 10 years on average. Since abnormal decrease of BMF is easy to be found, programs could be set up for the early screening of PD in older people, along with other early symptoms of PD.

m6A mRNA methylation regulates CTNNB1 to promote the proliferation of hepatoblastoma

Background

N⁶-Methyladenosine (m⁶A) modification has been implicated in many biological processes. It is important for the regulation of messenger RNA (mRNA) stability, splicing, and translation. However, its role in cancer has not been studied in detail. Here we investigated the biological role and underlying mechanism of m⁶A modification in hepatoblastoma (HB).

Methods

We used Reverse transcription quantitative real-time PCR (RT-qPCR) and Western blotting to determine the expression of m⁶A related factors. And we clarified the effects of these factors on HB cells using cell proliferation assay, colony formation, apoptotic assay. Then we investigated of methyltransferase-like 13 (METTL3) and its correlation with clinicopathological features and used xenograft experiment to check METTL3 effect in vivo. m⁶A-Seq was used to profiled m⁶A transcriptome-wide in hepatoblastoma tumor tissue and normal tissue. Finally, methylated RNA immunoprecipitation (MeRIP) assay, RNA remaining assay to perform the regulator mechanism of MEETL3 on the target CTNNB1 in HB.

Results

In this research, we discovered that m⁶A modifications are increased in hepatoblastoma, and METTL3 is the main factor involved with aberrant m⁶A modification. We also profiled m⁶A across the whole transcriptome in hepatoblastoma tumor tissues and normal tissues. Our findings suggest that m⁶A is highly expressed in hepatoblastoma tumors. Also, m⁶A is enriched not only around the stop codon, but also around the coding sequence (CDS) region. Gene ontology analysis indicates that m⁶A mRNA methylation contributes significantly to regulate the Wnt/β-catenin pathway. Reduced m⁶A methylation can lead to a decrease in expression and stability of the CTNNB1.

Conclusion

Overall our findings suggest enhanced m⁶A mRNA methylation as an oncogenic mechanism in hepatoblastoma, METTL3 is significantly up-regulated in HB and promotes HB development. And identify CTNNB1 as a regulator of METTL3 guided m⁶A modification in HB.

Global profiling of O-GlcNAcylated and/or phosphorylated proteins in hepatoblastoma

O-linked-β-N-acetylglucosamine (O-GlcNAc) glycosylation (O-GlcNAcylation) and phosphorylation are critical posttranslational modifications that are involved in regulating the functions of proteins involved in tumorigenesis and the development of various solid tumors. However, a detailed characterization of the patterns of these modifications at the peptide or protein level in hepatoblastoma (HB), a highly malignant primary hepatic tumor with an extremely low incidence in children, has not been performed. Here, we examined O-GlcNAc-modified or phospho-modified peptides and proteins in HB through quantitative proteomic analysis of HB tissues and paired normal liver tissues. Our results identified 114 O-GlcNAcylated peptides belonging to 78 proteins and 3494 phosphorylated peptides in 2088 proteins. Interestingly, 41 proteins were modified by both O-GlcNAcylation and phosphorylation. These proteins are involved in multiple molecular and cellular processes, including chromatin remodeling, transcription, translation, transportation, and organelle organization. In addition, we verified the accuracy of the proteomics results and found a competitive inhibitory effect between O-GlcNAcylation and phosphorylation of HSPB1. Further, O-GlcNAcylation modification of HSPB1 promoted proliferation and enhanced the chemotherapeutic resistance of HB cell lines in vitro. Collectively, our research suggests that O-GlcNAc-modified and/or phospho-modified proteins may play a crucial role in the pathogenesis of HB.

P5505Inflammation implicated in the aetiology of major vascular and non-vascular diseases in East Asians

Background

Mendelian randomisation (MR) studies using genetic variants in the IL6R gene encoding the interleukin-6 (IL-6) receptor have demonstrated that IL-6 plays a causal role in the aetiology of coronary heart disease (CHD) in European populations, with implications for the development of drugs targeting inflammation-related pathways. It is less clear whether IL-6 signalling plays a causal role in vascular disease or major non-vascular diseases in East Asians.

Purpose

Using an MR approach, we investigated associations of altered IL-6 signalling with subtypes of CHD, stroke, cancer and respiratory disease in a large East Asian cohort.

Methods

In approximately 150,000 Chinese adults from the China Kadoorie Biobank, we investigated associations of rs7529229 (in strong linkage disequilibrium, r2=0.99, with the IL6R Asp358Ala variant rs2228145) with blood biomarkers and selected disease events in which inflammation has previously been implicated. First, we used linear regression to quantify the per-allele association of rs7529229 with levels in plasma of log-transformed C-reactive protein (CRP) (n=17,866), fibrinogen (n=9,255), and IL-6 protein (n=633). Second, we used logistic regression to evaluate the association of rs7529229 with incidence of CHD, stroke, cancer, and respiratory disease events. All models were adjusted for age, age-squared, sex (except breast cancer), and case ascertainment (for CRP and fibrinogen), and stratified by recruitment region. We assessed significance at a 5% false discovery rate.

Results

IL6R rs7529229 C-allele was associated with lower log CRP (–0.11 SDs per C-allele; p=4.9x10–25) and log fibrinogen (–0.07 SDs; p=2.2x10–7), and higher log IL-6 (0.15 SDs; p=0.011) (Figure 1), mimicking therapeutic blockade of IL6R. IL6R rs7529229 was associated with a lower risk of acute myocardial infarction (n=4,047 cases; OR: 0.92 [95% CI 0.88–0.96] per C-allele; p=2.8x10–4), with the association similar for fatal and non-fatal cases (Figure 2). There was no evidence of association with ischaemic stroke (n=18,315; OR: 1.00 [0.98–1.03]; p=0.90) or intracerebral haemorrhage (n=7,372; OR: 1.03 [0.99–1.07]; p=0.10). For non-cardiovascular diseases, the IL6R rs7529229 was associated with a lower risk of oesophageal (n=824; OR: 0.88 [0.79–0.97] per C-allele; p=0.013) and colorectal (n=1,151; OR: 0.89 [0.82–0.97]; p=8.3x10–3) cancers, but a higher risk of tuberculosis (n=1,017; OR: 1.15 [1.05–1.26]; p=2.4x10–3).

Conclusion

The results of the present study are consistent with a causal role for the IL-6 signalling pathway in the aetiology of myocardial infarction and some cancers, but not of stroke. These findings provide further genetic support for drug development targeting inflammation in the prevention and treatment of coronary and selected cancer outcomes.

Acknowledgement/Funding

Kadoorie Charitable Foundation, UK Wellcome Trust, Chinese Ministry of Science and Technology, BHF, CRUK, NIHR

P2494Cardiovascular disease burden attributed to high blood pressure in Chinese adults with type 2 diabetes

Background

Cardiovascular diseases (CVD) are the most common cause of death among people with diabetes, reflecting in part co-existence with other CVD risk factors, including high blood pressure. However, controversy persists about the nature of the relationship of blood pressure with risk of CVD in individuals with diabetes, and about the associated disease burden.

Methods

We analysed data from 26,315 men and women aged 30–79 years with type 2 diabetes but no prior history of CVD, who were recruited into the China Kadoorie Biobank in 2004–2008 from 10 diverse areas in China. During ∼10 years' follow-up 1,190 major coronary events (MCE), 4,362 ischaemic stroke (IS), 469 intra-cerebral haemorrhage (ICH) events and 4,503 deaths (including 1,807 CVD deaths) were recorded. Usual systolic (SBP) and diastolic (DBP) blood pressure and uncontrolled hypertension were related to risks of incident CVD and all-cause mortality, after adjustment for relevant confounders.

Results

Overall, 75.7% of participants had prior doctor-diagnosed (24.8%) or screen-detected (67.7%) hypertension, compared with 54.3% among those without diabetes. The age-adjusted prevalence of hypertension was higher among men and in rural areas. Among those with previously diagnosed hypertension, 39.3% reported use of anti-hypertensive medications (on average, 1 agent) and 8.5% had controlled hypertension (<130/80 mmHg). Usual SBP was continuously and positively associated with the risk of CVD, with no evidence of a threshold throughout the range examined (120–180 mmHg). Each 10 mmHg higher SBP was associated with a 27% higher risk for CVD death (HR 1.27, 95% CI 1.25–1.30). Strong positive associations were also seen for MCE (1.16, 1.12–1.21), IS (1.15, 1.13–1.18), and ICH (1.46, 1.34–1.60). Overall, uncontrolled hypertension accounts for an estimated 39% (32–45%), 30% (21–38%), 24% (20–28%) and 48% (34–58%) of CVD deaths, MCE, IS and ICH, respectively, among Chinese adults with diabetes.

Conclusion

Hypertension is common but frequently undetected and uncontrolled among adults with type 2 diabetes in China. Effective diagnosis and management of hypertension among individuals with diabetes would be expected to achieve substantial reductions in CVD morbidity and mortality.

Acknowledgement/Funding

Wellcome Trust, MRC, BHF, CR-UK, Kadoorie Foundation, MoST, NSFC

P2780Accuracy of electronic healthcare records for diagnosis of stroke types in a large community-based prospective cohort study in China

Background and purpose

Reliable assessment of the determinants of major pathological types of stroke is dependent on the accuracy of diagnosis in population-based studies. We evaluated the diagnostic accuracy of stroke types in a large community-based cohort study involving health records collected in China.

Methods

In 2004–08, >0.5 million adults aged 30–79 years were recruited from general populations of 10 diverse areas (5 urban, 5 rural) in China. During an approximate 7-year follow-up, 37,694 stroke cases had been reported by linkage to electronic health records from disease-specific and mortality registries and from national health insurance agencies. For all reported stroke cases, hospital medical records were retrieved systematically and relevant data extracted for subsequent adjudication by specialists using bespoke electronic platforms.

Results

Among all reported incident stroke cases, 80% were ischaemic stroke (IS), 17% were intracerebral haemorrhage (ICH), and 1% were subarachnoid haemorrhage (SAH). To date, medical records have been retrieved for 29,632 cases, with reports of stroke diagnosis verified by public health staff in 27,115 (92%) cases, of which 3,778 (14%) were secondary diagnoses. Evidence of neuroimaging was found in 92% of all verified stroke cases. Of 23,337 primary stroke cases sent for specialist adjudication, a diagnosis of pathological stroke type was confirmed in 19,718 cases with the positive predictive values being 82.4% (95% confidence interval [CI], 82.0% - 82.8%) for IS, 97.8% (97.6 - 97.9) for ICH, and 98.2% (98.1 - 98.3) for SAH. Overall, the strength of association of systolic blood pressure was over 6-fold greater for confirmed than non-confirmed stroke cases and was nearly 3-fold greater for confirmed ICH than IS cases.

Diagnostic accuracy by stroke type Reported Retrieved Verified Adjudicated Confirmed Approximate 95% CI n n % n % n % n PPV, % IS 30,143 25,477 85 23,551 92 20,045 85 16,515 82.4 (82.0–82.8) ICH 6,484 3,486 54 3,079 88 2,919 95 2,854 97.8 (97.6–97.9) SAH 557 397 71 326 82 279 86 274 98.2 (98.1–98.3) Other 510 272 53 159 59 94 59 75 79.8 (79.4–80.2) IS indicates ischaemic stroke; ICH, intracerebral haemorrhage; SAH, subarachnoid haemorrhage; and PPV, positive predictive value.

Conclusions

The overall diagnostic accuracy of pathological stroke types obtained from hospital records in China is comparable to reports from Western populations. Despite advances in electronic healthcare records, reliable classification of stroke types requires clinical adjudication using additional relevant investigations.

Acknowledgement/Funding

Kadoorie Charitable Foundation, UK Wellcome Trust & National Natural Science Foundation and National Key Research and Development Program of China

O-GlcNAcylation of YY1 stimulates tumorigenesis in colorectal cancer cells by targeting SLC22A15 and AANAT

Emerging studies have revealed that O-GlcNAcylation plays pivotal roles in the tumorigenesis of colorectal cancers (CRCs). However, the underlying mechanism still remains largely unknown. Here, we demonstrated that Yin Yang 1 (YY1) was O-GlcNAcylated by O-GlcNAc transferase (OGT) and O-GlcNAcylation of YY1 could increase the protein expression by enhancing its stability. O-GlcNAcylation facilitated transformative phenotypes of CRC cell in a YY1-dependent manner. Also, O-GlcNAcylation stimulates YY1-dependent transcriptional activity. Besides, we also identified the oncoproteins, SLC22A15 and AANAT, which were regulated by YY1 directly, are responsible for the YY1 stimulated tumorigenesis. Furthermore, we identified the main putative O-GlcNAc site of YY1 at Thr236, and mutating of this site decreased the pro-tumorigenic capacities of YY1. We concluded that O-GlcNAcylation of YY1 stimulates tumorigenesis in CRC cells by targeting SLC22A15 and AANAT, suggesting that YY1 O-GlcNAcylation might be a potential effective therapeutic target for treating CRC.

[Epidemiological characteristics and correlated factors of habitual snoring among Chinese aged 30 to 79 year-old]

Objective: To describe the characteristics of habitual snoring among adults from 10 regions engaged in the China Kadoorie Biobank (CKB) study. Methods: The baseline survey of CKB was conducted from 2004 to 2008. Data was collected regarding the information on socio- demographic characteristics, lifestyle, sleeping habits, and results from the physical examination of the participants. Logistic regression models were used to compare the regional differences and to estimate the associations of other baseline characteristics on snoring habit. Results: A total of 512 713 participants were included in this study. The overall prevalence of habitual snoring was 21.2%, higher among men, in south regions and urban areas, but no difference observed among people with different socioeconomic status after adjusting for age, regions, BMI, waist circumference or lifestyle factors. Results showed that the prevalence of habitual snoring under the multivariable adjusted model increased among current and ever smokers, also among current and ever alcohol consumers. The risk of habitual snoring was increased by 19% per 1 kg/m(2) and 6% per 1 cm increment in BMI or waist circumference, respectively. Among participants with similar BMI, central obese individuals were more likely to be habitual snorers. For individuals with similar waist circumference, the prevalence of habitual snoring was higher among those with higher BMI. Conclusion: The prevalence of habitual snoring varied across regions. Substantial differences in habitual snoring were also seen among people with different lifestyles and body sizes.