Maize requires Arogenate Dehydratase 2 for resistance to Ustilago maydis and plant development

Maize (Zea mays) smut is a common biotrophic fungal disease caused by Ustilago maydis and leads to low maize yield. Maize resistance to U. maydis is a quantitative trait. However, the molecular mechanism underlying the resistance of maize to U. maydis is poorly understood. Here, we reported that a maize mutant caused by a single gene mutation exhibited defects in both fungal resistance and plant development. maize mutant highly susceptible to U. maydis (mmsu) with a dwarf phenotype forms tumors in the ear. A map-based cloning and allelism test demonstrated that one gene encoding a putative arogenate dehydratase/prephenate dehydratase (ADT/PDT) is responsible for the phenotypes of the mmsu and was designated as ZmADT2. Combined transcriptomic and metabolomic analyses revealed that mmsu had substantial differences in multiple metabolic pathways in response to U. maydis infection compared with the wild type. Disruption of ZmADT2 caused damage to the chloroplast ultrastructure and function, metabolic flux redirection, and reduced the amounts of salicylic acid (SA) and lignin, leading to susceptibility to U. maydis and dwarf phenotype. These results suggested that ZmADT2 is required for maintaining metabolic flux, as well as resistance to U. maydis and plant development in maize. Meanwhile, our findings provided insights into the maize response mechanism to U. maydis infection.

[Deep learning-assisted construction of three-dimensional face midsagittal plane based on point clouds]

Objective: To establish an intelligent registration algorithm under the framework of original-mirror alignment algorithm to construct three-dimensional(3D) facial midsagittal plane automatically. Dynamic Graph Registration Network (DGRNet) was established to realize the intelligent registration, in order to provide a reference for clinical digital design and analysis. Methods: Two hundred clinical patients without significant facial deformities were collected from October 2020 to October 2022 at Peking University School and Hospital of Stomatology. The DGRNet consists of constructing the feature vectors of key points in point original and mirror point clouds (X, Y), obtaining the correspondence of key points, and calculating the rotation and translation by singular value decomposition. Original and mirror point clouds were registrated and united. The principal component analysis (PCA) algorithm was used to obtain the DGRNet alignment midsagittal plane. The model was evaluated based on the coefficient of determination (R2) index for the translation and rotation matrix of test set. The angle error was evaluated on the 3D facial midsagittal plane constructed by the DGRNet alignment midsagittal plane and the iterative closet point(ICP) alignment midsagittal plane for 50 cases of clinical facial data. Results: The average angle error of the DGRNet alignment midsagittal plane and ICP alignment midsagittal plane was 1.05°±0.56°, and the minimum angle error was only 0.13°. The successful detection rate was 78%(39/50) within 1.50° and 90% (45/50)within 2.00°. Conclusions: This study proposes a new solution for the construction of 3D facial midsagittal plane based on the DGRNet alignment method with intelligent registration, which can improve the efficiency and effectiveness of treatment to some extent.

Defective kernel 66 encodes a GTPase essential for kernel development in maize

The mitochondrion is a semi-autonomous organelle that provides energy for cell activities through oxidative phosphorylation. In this study, we identified a defective kernel 66 (dek66)-mutant maize with defective kernels. We characterized a candidate gene, DEK66, encoding a ribosomal assembly factor located in mitochondria and possessing GTPase activity (which belongs to the ribosome biogenesis GTPase A family). In the dek66 mutant, impairment of mitochondrial structure and function led to the accumulation of reactive oxygen species and promoted programmed cell death in endosperm cells. Furthermore, the transcript levels of most of the key genes associated with nutrient storage, mitochondrial respiratory chain complex, and mitochondrial ribosomes in the dek66 mutant were significantly altered. Collectively, the results suggest that DEK66 is essential for the development of maize kernels by affecting mitochondrial function. This study provides a reference for understanding the impact of a mitochondrial ribosomal assembly factor in maize kernel development.

[The predictive value of melanin-concentrating hormone combined with other related biomarkers in cerebrospinal fluid in preoperative cognitive dysfunction of elderly patients]

Objective: To explore the predictive value of cerebrospinal fluid melanin-concentrating hormone (MCH) combined with other related biomarkers in preoperative cognitive dysfunction of elderly patients. Methods: A total of 80 patients who underwent elective hip or knee replacement under intravertebral anesthesia in Chifeng Municipal Hospital, Inner Mongolia, from March to November 2022 were prospectively included, with 32 males and 48 females, and aged 65-85 (70.7±5.2) years old. According to the evaluation results of the Montreal Cognitive Assessment (MoCA), patients were divided into the preoperative cognitive dysfunction (n=23) and control (n=57) groups. The levels of MCH, amyloid-β 40 (Aβ40), amyloid-β 42 (Aβ42), and phosphorylated tau protein (p-tau) in cerebrospinal fluid were determined by enzyme-linked immunosorbent assay (ELISA). The receiver operating characteristic (ROC) curve was drawn to evaluate the predictive value of each biomarker separately or in combination for preoperative cognitive dysfunction. Spearman's rank correlation analysis was utilized to test the correlation between the level of each biomarker and MoCA scores. Results: The levels of MCH, Aβ40, Aβ42, p-tau, and Aβ42/p-tau in the preoperative cognitive dysfunction group were (35.53±5.94) μg/L, (39.21±9.18) ng/L, (221.83±43.17) ng/L, (42.64±9.74) ng/L, and 5.53±1.92, and the levels of these biomarkers in the control group were (28.74±4.90) μg/L, (36.37±7.87) ng/L, (280.23±45.67) ng/L, (35.00±9.27) ng/L, and 8.62±2.78, respectively. Compared with the control group, the levels of cerebrospinal fluid MCH and p-tau in the preoperative cognitive dysfunction group were significantly increased (all P<0.01), and the levels of Aβ42 and Aβ42/p-tau were significantly decreased (all P<0.001). MCH and Aβ42/p-tau provided higher predictive values. The area under the curve (AUC) of MCH and Aβ42/p-tau were 0.807 (95%CI: 0.703-0.911) and 0.842 (95%CI: 0.741-0.943), the sensitivity were 78.3% and 87.0%, and the specificity were 75.4% and 94.7%. MCH combined with Aβ42/p-tau have the higher AUC of 0.915 (95%CI: 0.837-0.992), the sensitivity (87.0%) and specificity (86.0%) were both high, which had a higher predictive value. The levels of cerebrospinal fluid MCH and p-tau were negatively correlated with MoCA score (r=-0.467, -0.321, all P<0.01), and the levels of Aβ42 and Aβ42/p-tau were positively correlated with MoCA score (r=0.480, 0.520, all P<0.001). Conclusion: The increase in cerebrospinal fluid MCH levels is associated with preoperative cognitive dysfunction in elderly patients. MCH combined with Aβ42/p-tau has the greatest predictive value.

[Analysis of mortality trend and characteristic of chronic obstructive pulmonary disease among residents in China from 2004 to 2020]

Objective: To analyze the mortality trend and characteristics of chronic obstructive pulmonary disease (COPD) among residents in China from 2004 to 2020. Methods: From the area, gender, region, and age dimensions, the Joinpoint regression model was used to analyze the trend of COPD mortality rate from 2004 to 2020, extracted from the China Death Surveillance Dataset. Results: From 2004 to 2020, the mortality rate and age-adjusted mortality rate of COPD showed a downward trend (AAPC=-3.68%, P<0.001; AAPC=-7.27%, P<0.001), which were consistent with urban and rural subpopulations (mortality rate: AAPC=-3.62%, P=0.009, AAPC=-3.23%, P=0.014; age-adjusted mortality rate: AAPC=-7.26%, P<0.001, AAPC=-6.78%, P<0.001). The mortality rate of COPD in rural was higher than that of urban subpopulations (P<0.001). Also, the mortality rate and age-adjusted mortality rate of COPD showed a downward trend in males and females (mortality rate: AAPC=-3.00%, P<0.001, AAPC=-4.37%, P<0.001; age-adjusted mortality rate: AAPC=-6.73%, P<0.001, AAPC=-8.11%, P<0.001), and the COPD mortality rate for male was generally higher than female (P<0.001). Meanwhile, the mortality rate of COPD in eastern, central and western regions also showed a downward trend (AAPC=-3.87%, P<0.001; AAPC=-3.12%, P<0.001; AAPC=-1.37%, P=0.001), and western regions were significantly higher than that in central (P<0.001) and eastern (P<0.001) regions. The mortality rate of COPD in the age group of Chinese people showed a downward trend in<45, 45-59, and≥60 years groups (AAPC=-9.48%, P<0.001; AAPC=-9.03%, P<0.001; AAPC=-5.91%, P<0.001). Among them,≥60 years groups was significantly higher than that in<45 (P<0.001) and 45-59 (P<0.001) years groups, and the decline rate was slowest. Conclusion: In China, the mortality rate of COPD decreases from 2004 to 2020, and more efforts are needed to reduce COPD mortality, especially in western regions, rural populations, males and the elderly.

[Study on the method of automatically determining maxillary complex landmarks based on non-rigid registration algorithms]

Objective: To explore an automatic landmarking method for anatomical landmarks in the three-dimensional (3D) data of the maxillary complex and preliminarily evaluate its reproducibility and accuracy. Methods: From June 2021 to December 2022, spiral CT data of 31 patients with relatively normal craniofacial morphology were selected from those who visited the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. The sample included 15 males and 16 females, with the age of (33.3±8.3) years. The maxillary complex was reconstructed in 3D using Mimics software, and the resulting 3D data of the maxillary complex was mesh-refined using Geomagic software. Two attending physicians and one associate chief physician manually landmarked the 31 maxillary complex datasets, determining 24 anatomical landmarks. The average values of the three expert landmarking results were used as the expert-defined landmarks. One case that conformed to the average 3D morphological characteristics of healthy individuals' craniofacial bones was selected as the template data, while the remaining 30 cases were used as target data. The open-source MeshMonk program (a non-rigid registration algorithm) was used to perform an initial alignment of the template and target data based on 4 landmarks (nasion, left and right zygomatic arch prominence, and anterior nasal spine). The template data was then deformed to the shape of the target data using a non-rigid registration algorithm, resulting in the deformed template data. Based on the unchanged index property of homonymous landmarks before and after deformation of the template data, the coordinates of each landmark in the deformed template data were automatically retrieved as the automatic landmarking coordinates of the homonymous landmarks in the target data, thus completing the automatic landmarking process. The automatic landmarking process for the 30 target data was repeated three times. The root-mean-square distance (RMSD) of the dense corresponding point pairs (approximately 25 000 pairs) between the deformed template data and the target data was calculated as the deformation error of the non-rigid registration algorithm, and the intra-class correlation efficient (ICC) of the deformation error in the three repetitions was analyzed. The linear distances between the automatic landmarking results and the expert-defined landmarks for the 24 anatomical landmarks were calculated as the automatic landmarking errors, and the ICC values of the 3D coordinates in the three automatic landmarking repetitions were analyzed. Results: The average three-dimensional deviation (RMSD) between the deformed template data and the corresponding target data for the 30 cases was (0.70±0.09) mm, with an ICC value of 1.00 for the deformation error in the three repetitions of the non-rigid registration algorithm. The average automatic landmarking error for the 24 anatomical landmarks was (1.86±0.30) mm, with the smallest error at the anterior nasal spine (0.65±0.24) mm and the largest error at the left oribital (3.27±2.28) mm. The ICC values for the 3D coordinates in the three automatic landmarking repetitions were all 1.00. Conclusions: This study established an automatic landmarking method for three-dimensional data of the maxillary complex based on a non-rigid registration algorithm. The accuracy and repeatability of this method for landmarking normal maxillary complex 3D data were relatively good.

[Advances in algorithms for three-dimensional craniomaxillofacial features construction based on point clouds]

In light of the increasing digitalization of dentistry, the automatic determination of three-dimensional (3D) craniomaxillofacial features has become a development trend. 3D craniomaxillofacial landmarks and symmetry reference plane determination algorithm based on point clouds has attracted a lot of attention, for point clouds are the basis for virtual surgery design and facial asymmetry analysis, which play a key role in craniomaxillofacial surgery and orthodontic treatment design. Based on the studies of our team and national and international literatures, this article presented the deep geometry learning algorithm to determine landmarks and symmetry reference plane based on 3D craniomaxillofacial point clouds. In order to provide reference for future clinical application, we describe the development and latest research in this field, and analyze and discuss the advantages and limitations of various methods.

[Preliminary study on three-dimensional morphological reconstruction method for external nose defect based on three-dimensional face template]

Objective: To provide a new solution for the digital design of nasal prostheses, this study explores the three-dimensional (3D) facial morphology completion method for external nasal defects based on the non-rigid registration process of 3D face template. Methods: A total of 20 male patients with tooth defect and dentition defect who visited the Department of Prosthodontics, Peking University School and Hospital of Stomatology from June to December 2022 were selected, age 18-45 years old. The original 3D facial data of patients were collected, and the 3D facial data of the external nose defect was constructed in Geomagic Wrap 2021 software. Using the structured 3D face template data constructed in the previous research of the research group, the 3D face template was deformed and registered to the 3D facial data of external nose defect (based on the morphology of non-defective area) by non-rigid registration algorithm (MeshMonk program), and the personalized deformed data of the 3D face template was obtained, as the complemented facial 3D data. Based on the defect boundary of the 3D facial data of the external nose defect, the complemented external nose 3D data can be cut out from the complemented facial 3D data. Then the nasofacial angle and nasolabial angle of the complemented facial 3D data and the original 3D facial data was compared and analyzed, the ratio between the nose length and mid-face height, nose width and medial canthal distance of the complemented facial 3D data was measured, the edge fit between the edge curve of the complemented external nose 3D data and the defect edge curve of the 3D facial data of external nose defect was evaluated, and the morphological difference of the nose between the complemented external nose 3D data and the original 3D facial data was analyzed. Results: There was no significant statistically difference (t=-0.23, P=0.823; Z=-1.72, P=0.086) in the nasofacial angle (28.2°±2.9°, 28.4°±3.5° respectively) and nasolabial angle [95.4°(19.2°), 99.9°(9.5°) respectively] between the 20 original 3D facial data and the complemented facial 3D data. The value of the ratio of nose length to mid-face height in the complemented facial 3D data was 0.63±0.03, and the value of the ratio of nose width to medial canthal distance was 1.07±0.08. The curve deviation (root mean square value) between the edge curve of the complemented external nose 3D data and the defect edge curve of the 3D facial data of external nose defect was (0.37±0.09) mm, the maximum deviation was (1.14±0.32) mm, and the proportion of the curve deviation value within±1 mm was (97±3)%. The distance of corresponding nose landmarks between the complemented facial 3D data and the original 3D facial data were respectively, Nasion: [1.52(1.92)] mm; Pronasale: (3.27±1.21) mm; Subnasale: (1.99±1.09) mm; Right Alare: (2.64±1.34) mm; Left Alare: (2.42± 1.38) mm. Conclusions: The method of 3D facial morphology completion of external nose defect proposed in this study has good feasibility. The constructed complemented external nose 3D data has good facial coordination and edge fit, and the morphology is close to the nose morphology of the original 3D facial data.

[The design method of the digital sequential tooth-sectioning guide for the extraction of mandibular impacted third molars]

Objective: To explore a method for digitally designing and fabricating a sequential tooth-sectioning guide that can assist in the extraction of mandibular horizontal impacted third molars, preliminarily evaluate its feasibility and provide a reference for clinical application. Methods: Twenty patients with mandibular low level impacted third molars who visited the Department of General Dentistry, Peking University School and Hospital of Stomatology from March 2021 to January 2022 were selected. Cone-beam CT showed direct contact between the roots and mandibular canal, and full range impressions of the patients' intraoral teeth were taken and optical scans of the dental model were performed. The patients' cone-beam CT data and optical scan data were reconstructed in three dimensions, anatomical structure extraction, registration fusion, and the design of the structure of the guide (including crown-sectioning guide and root-sectioning guide) by Mimics 24.0, Geomagic Wrap 2021, and Magics 21.0 software, and then the titanium guide was three dimension printed, and the guide was tried on the dental model. After confirmation, the guide was used to assist the dentist in the operation. We observed whether the guide was in place, the number of tooth splitting, the matching of tooth splitting with the preoperative design, the operation time, and whether there were any complications. Results: In this study, 20 sectioning guides were successfully printed, all of them were well fitted in the patients' mouth, the average number of section was 3.4 times, the tooth parts was better matched with the preoperative design, and the average operative time of the guides was (29.2±9.8) minutes without complications such as perforation of the bone cortex. Conclusions: The use of sequential sectioning guides to assist in the extraction of mandibular impacted third molars was initially validated to accurately replicate the preoperative sectioning design, and is expected to provide a digital solution to improve surgical precision and ensure safety. Further studies with larger sample sizes are needed to evaluate its accuracy and safety.

[Clinical and genetic characteristic in patients with disorders of sex development caused by Y chromosome copy number variant]

Objective: To investigate the clinical phenotype and genetic characteristics of disorders of sex development (DSD) caused by Y chromosome copy number variant (CNV). Methods: A retrospective analysis was performed on 3 patients diagnosed with DSD caused by Y chromosome CNV admitted to the First Affiliated Hospital of Zhengzhou University from January, 2018 to September, 2022. Clinical data were collected. Clinical study and genetic test were performed by karyotyping, whole exome sequencing (WES), low coverage whole genome copy number variant sequencing (CNV-seq), fluorescence in situ hybridization (FISH) and gonadal biopsy. Results: The 3 children, aged 12, 9, 9 years, the social gender were all female, presented with short stature, gonadal dysplasia and normal female external genital. No other phenotypic abnormality was found except for case 1 with scoliosis. The karyotype of all cases were identified as 46, XY. No pathogenic vraiants were found by WES. CNV-seq determined that case 1 was 47, XYY,+Y(2.12) and case 2 was 46, XY,+Y(1.6). FISH concluded that the long arm of Y chromosome was broken and recombined near Yq11.2, and then produced a pseudodicentric chromosome idic(Y). The karyotype was reinterpreted as mos 47, X, idic(Y)(q11.23)×2(10)/46, X, idic(Y)(q11.23)(50) in case 1. The karyotype was redefined as 45, XO(6)/46, X, idic(Y)(q11.22)(23)/46, X, del(Y)(q11.22)(1) in case 2. 46, XY, -Y(mos) was found by CNV-seq in case 3, and the karyotype of 45, XO/46, XY was speculated. Conclusions: The clinical manifestations of children with DSD caused by Y chromosome CNV are short stature and gonadal dysgenesis. If there is an increase of Y chromosome CNV detected by CNV-seq, FISH is recommended to classify the structural variation of Y chromosome.

[Preliminary evaluation of the trueness of 5 chairside 3D facial scanning techniques]

OBJECTIVE

To quantitatively evaluate the trueness of five chairside three-dimensional facial scanning techniques, and to provide reference for the application of oral clinical diagnosis and treatment.

METHODS

The three-dimensional facial data of the subjects were collected by the traditional professional three-dimensional facial scanner Face Scan, which was used as the reference data of this study. Four kinds of portable three-dimensional facial scanners (including Space Spider, LEO, EVA and DS-FScan) and iPhone Ⅹ mobile phone (Bellus3D facial scanning APP) were used to collect three-dimensional facial data from the subjects. In Geomagic Studio 2013 software, through data registration, deviation analysis and other functions, the overall three-dimensional deviation and facial partition three-dimensional deviation of the above five chairside three-dimensional facial scanning technologies were calculated, and their trueness performance evaluated. Scanning time was recorded during the scanning process, and the subject's comfort was scored by visual analogue scale(VAS). The scanning efficiency and patient acceptance of the five three-dimensional facial scanning techniques were evaluated.

RESULTS

DS-FScan had the smallest mean overall and mean partition three-dimensional deviation between the test data and the reference data, which were 0.334 mm and 0.329 mm, respectively. The iPhone Ⅹ mobile phone had the largest mean overall and mean partition three-dimensional deviation between the test data and the reference data, which were 0.483 mm and 0.497 mm, respectively. The detailed features of the three-dimensional facial data obtained by Space Spider were the best. The iPhone Ⅹ mobile phone had the highest scanning efficiency and the highest acceptance by the subject. The average scanning time of the iPhone Ⅹ mobile phone was 14 s, and the VAS score of the subjects' scanning comfort was 9 points.

CONCLUSION

Among the five chairside three-dimensional face scanning technologies, the trueness of the scan data of the four portable devices had no significant difference, and they were all better than the iPhone Ⅹ mobile phone scan. The subject with the iPhone Ⅹ scanning technology had the best expe-rience.

Effect of Avian Influenza Virus subtype H9N2 on the expression of complement-associated genes in chicken erythrocytes

The H9N2 subtype avian influenza virus can infect both chickens and humans. Previous studies have reported a role for erythrocytes in immunity. However, the role of H9N2 against chicken erythrocytes and the presence of complement-related genes in erythrocytes has not been studied. This research investigated the effect of H9N2 on complement-associated gene expression in chicken erythrocytes. The expression of complement-associated genes (C1s, C1q, C2, C3, C3ar1, C4, C4a, C5, C5ar1, C7, CD93 and CFD) was detected by reverse transcription-polymerase chain reaction (RT-PCR). Quantitative Real-Time PCR (qRT-PCR) was used to analyse the differential expression of complement-associated genes in chicken erythrocytes at 0 h, 2 h, 6 h and 10 h after the interaction between H9N2 virus and chicken erythrocytes in vitro and 3, 7 and 14 d after H9N2 virus nasal infection of chicks. Expression levels of C1q, C4, C1s, C2, C3, C5, C7 and CD93 were significantly up-regulated at 2 h and significantly down-regulated at 10 h. Gene expression levels of C1q, C3ar1, C4a, CFD and C5ar1 were seen to be different at each time point. The expression levels of C1q, C4, C1s, C2, C3, C5, C7, CFD, C3ar1, C4a and C5ar1 were significantly up-regulated at 7 d and the gene expression of levels of C3, CD93 and C5ar1 were seen to be different at each time point. The results confirmed that all the complement-associated genes were expressed in chicken erythrocytes and showed the H9N2 virus interaction with chicken erythrocytes and subsequent regulation of chicken erythrocyte complement-associated genes expression. This study reported, for the first time, the relationship between H9N2 and complement system of chicken erythrocytes, which will provide a foundation for further research into the prevention and control of H9N2 infection.

[Materia medica illustrations related to the regional names in Zhejiang province in Ben Cao Tu Jing]

Ben Cao Tu Jing had 38 materia medica illustrations related to the regional names in Zhejiang province. It was found that 30 of them were identified as being named after regional names in Zhejiang province, involving 20 families and 29 genera. One of the 38 materia medica illustrations was mineral medicine and seven of them were unverified. The twenty-five of these materia medica illustrations with regional names were found to be consistent with their names used today. Five of them came from similar names in Zhejiang province in the Northern Song Dynasty, another five of the 25 names were known with the names but not entity for the lack of full descriptions and drawings. It was found that the drawing and the text of "Ming Zhou Huang Yao" and "Qin Zhou Hong Yao" in Ben Cao Tu Jing were reversed. By comparing the materia medica illustrations related to regional names in Da Guan Ben Cao by Liu Jia and Zheng He Ben Cao by Zhang Huicun, the name and the illustration of "Jin Zhou Bei Mu" in Zheng He Ben Cao by Zhang Huicun was more believable than "Yue Zhou Bei Mu" in Da Guan Ben Cao by Liu Jia. "Tai Zhou Wu Yao" and "Zhe Ba Wei", as genuine medicinal materials in Zhejiang, can be traced back to the illustrations of "Tai Zhou Wu Yao", "Yue Zhou Bai Zhu", "Mu Zhou Mai Dong", "Wen Zhou Peng 'e Shu", "Yue Zhou Bei Mu" and "Tian Tai Wu Yao" in Ben Cao Tu Jing. These findings provided text and drawing literature of herbs in the Song Dynasty for the research of genuine medicinal materials and their characteristics in Zhejiang province. They also showed that the utilization and development of the resources of traditional Chinese medicine in Zhejiang in the Northern Song Dynasty mainly focused on the coastal areas.

Long-Term Cardiac Disease- and Cancer-Associated Mortalities in Patients With Non-Metastatic Stomach Adenocarcinoma Receiving Resection and Chemotherapy: A Large Competing-Risk Population-Based Cohort Study

Background

The survival of patients with non-metastatic gastric adenocarcinoma (nmGaC), who are receiving more and more frequently chemotherapy, has improved throughout the last decades, while treatment-caused cardiotoxicity remains a major concern. This study aimed to investigate competing causes of mortality and prognostic factors within a large cohort of patients with resected nmGaC, and to describe the heart-specific mortalities of patients undergoing resection and chemotherapy and of all resected patients.

Methods

In this population-based cohort study, data on patients diagnosed with nmGaC from 2004 through 2016, managed with resection with or without chemotherapy, followed up until the end of 2016, and surviving ≥ 1 month were retrieved from the US Surveillance, Epidemiology, and End Results-18 Program. Cumulative mortality functions were calculated. Prognostic factors for heart- and cancer-specific mortalities were evaluated using both multivariable-adjusted Fine-Gray subdistribution and cause-specific hazard functions.

Results

Together 21,257 patients with resected nmGaC were eligible for analysis with an accumulated follow-up of 73,711 person-years, where 10,718 (50%) also underwent chemotherapy. Mortalities were overestimated when using the Kaplan-Meier method. Heart diseases were the most common non-cancer cause of mortality. Compared with all resected patients, heart-specific mortality of those also receiving chemotherapy was lower overall and especially at older ages. In the total group of patients, the 8-year cumulative mortalities from heart diseases were 4.4% and 2.0% in resected patients and those also receiving chemotherapy, respectively; in patients ≥ 80 years, the heart disease-specific mortalities were as high as 11.1% and 6.5%, respectively. In overall patients undergoing resection, older ages, black ethnicity, and location at gastric antrum/pylorus were associated with increased heart-specific mortality, while more recent period, female sex, Asian/Pacific Islanders, invasion of serosa, and more positive lymph nodes were associated with lower heart-specific mortality; among those further receiving chemotherapy, only the associations with period of diagnosis, age, and ethnicity were significant. Associations with older ages were stronger for heart-specific mortality than for cancer-associated mortality.

Conclusions

Among survivors with resected nmGaC receiving chemotherapy, heart-specific mortality, the most common one among non-cancer causes of mortality, is not higher compared to overall resected patients in this observational study, suggesting that chemotherapy may be relatively safely administered to selected patients under strict indications. Age and ethnicity were major factors associated with heart-specific mortality in both overall resected patients and those further receiving chemotherapy. Overall and stratified cause-specific cumulative incidences of mortality are provided, which can be more clinically useful than the Kaplan-Meier estimates. Our study provides clinically useful evidence for tailored patient management.

[Design of non-metallic crown for primary molars and analyzation of stress distribution: a finite element study]

Objectives: To study the design of nonmetallic crowns for deciduous molars by means of computer aided design and to analyze the key parameters of the nonmetallic crowns of deciduous molars using finite element method. Methods: The three-dimensional model of a mandibular second primary molar was constructed by using a micro-CT system. The thickness of the crown was limited to 0.5 mm and four different crown shapes (chamfer+anatomic, chamfer+non-anatomic, knife edge+anatomic and knife edge+non-anatomic) were designed. Then, the crown shape was limited as chamfer+non-anatomic and five different thicknesses of the crown (0.50, 0.75, 1.00, 1.25, 1.50 mm) were designed, and three different materials, including polyetherketoneketone (PEKK), polymethylmethacrylate (PMMA) resin and resin-infiltrated ceramic, were applied to make the crown. Stress distribution and fatigue of each component of the model under vertical and oblique loadings were analyzed by using finite element method. Non-axial retention analysis was performed on chamfer+non-anatomic crowns, made of PMMA resin, with thicknesses of 0.50, 0.75, 1.00, 1.25 and 1.50 mm. Results: Among the four crown shape designs, the chamfer+non-anatomic type crown showed the lowest von Mises stress and the highest safety factor. By comparing three different materials, the resin-infiltrated ceramic group showed obvious stress concentration on the buccal edge of the crown and the PEKK group showed stress concentration in the adhesive layer. Results of non-axial retention analysis showed that the torques required by the crowns with five thicknesses at the same rotation angle were as follows: 4 856.1, 4 038.1, 3 497.3, 3 256.3 and 3 074.3 N⋅m, respectively. The comparison of areas of the adhesives fracture among groups were as follows: 0.5 mm group < 0.75 mm group < 1.00 mm group < 1.25 mm group < 1.50 mm group. Conclusions: In the design of nonmetallic crowns for primary molars, the edge of the crown should be designed as chamfer, the shape of the inner crown should be non-anatomical and the minimum preparation amount of the occlusal surface should be 1.00 mm. Among the three materials, PMMA resin, of which elastic modulus is similar to the dentin and the dental adhesive, might be the most suitable material for the crowns of primary molars.

[Types of medicine paintings in herbaceous and woody medicines in Ben Cao Tu Jing]

A total of 568 paintings of herbaceous plants and woody plants as medicine were involved in Ben Cao Tu Jing, accounting for 60% of the total drug illustrations and 76% of the botanical medicine paintings. These medicinal paintings can be classified into four types: original plant paintings, medicinal material paintings, plant and medicinal material paintings, and plant and their habitat paintings. The original plant paintings can be specifically divided into five sections: the whole plant paintings with roots, partial aerial part paintings with roots, plant paintings with ground lines, rootless plant paintings, and broken branch paintings. Among them, the drawings of " the broken branch paintings " and " the whole plant paintings with roots " are consistent with the basic principles of collecting plant specimens. Additionally, "the plant and medicinal material paintings " and "the medicinal material paintings "reflect that they were drawn based on the market survey of medicinal materials or collected medicinal materials specimens. These medicine painting demonstrate rich characteristics of medicinal plants and medicinal materials and a high artistic quality with realistic details.These paintings in Ben Cao Tu Jing echoes Tu Jing, combine the art of painting with the cognition ofnatural science, as the rudiment of early paintings of plant science.

[Performance of loop-mediated isothermal amplification (LAMP) assay for detection of Schistosoma japonicum infection in Oncomelania snails in schistosomiasis transmission-interrupted regions]

OBJECTIVE

To compare the effectiveness of loop-mediated isothermal amplification (LAMP) assay and microscopic examinations for detection of Schistosoma japonicum infections in Oncomelania hupensis in transmission-interrupted regions, so as to provide insights into the optimization of snail surveillance tools in these regions.

METHODS

Four hilly schistosomiasis-endemic villages where transmission interruption was achieved were selected in Heqing County of Yunnan Province as the study villages, including Xinzhuang and Gule villages in hilly regions and Lianyi and Yitou villages in dam regions. Snail survey was performed by means of systematic sampling combined with environmental sampling in July 2018. All captured snails were identified for S. japonicum infections using microscopy. In addition, 10 to 20 snails were randomly sampled from each snail habitat following microscopy, numbered according to environments and subjected to LAMP assay. The positive rate of settings with S. japonicum-infected snails was compared among villages.

RESULTS

A total of 7 949 living snails were captured from 83 snail habitats in 4 villages, and no S. japonicum infection was detected in snails. There were 226 mixed samples containing 1 786 snails subjected to LAMP assay, and positive LAMP assay was found in 3 mixed samples from 3 snail habitats in 2 dam villages. The positive rates of settings with S. japonicum-infected snails were comparable between Lianyi Village (one setting) and Yitou Village (2 set tings) (5.89% vs. 14.29%, P = 0.344). However, the overall positive rate of settings with S. japonicum-infected snails was significantly higher in dam villages (9.67%, 3/31) than in hilly villages (0) (P = 0.048).

CONCLUSIONS

LAMP assay is more sensitive to detect S. japonicum infections in O. hupensis than conventional microcopy method, which may serve as a supplementary method for detection of S. japonicum infections in O. hupensis in high-risk snail habitats in hilly transmission-interrupted regions.

[Interventional strategies and perioperative complications of chronic total coronary occlusion in combination with bifurcation lesions]

Objective: To analyze the clinical characteristics of chronic total coronary occlusion (CTO) combined with bifurcation lesions and the features of coronary intervention and perioperative complications. Methods: This study adopted retrospective cross-sectional research methods and included 673 patients who underwent interventional therapy for chronic total occlusion in Beijing Anzhen Hospital. According to whether there were side branches (diameter ≥2 mm) within 5 mm before and after the CTO occlusion segment, patients were divided into bifurcation group (337 cases) and non-bifurcation group (336 cases). The measurement data did not conform to the normal distribution and were represented as M (Q₁, Q₃). The clinical risk factors, coronary angiography characteristics, interventional treatment strategies and perioperative complications were compared between the two groups. Results: The patients in the bifurcation group were 60 (51, 65) years old, and 86.6% (292 cases) were male; the patients in the non-bifurcation group were 60 (52, 66) years old, and 83.0% (279 cases) were male.Coronary artery disease in all patients was mainly multivessel disease, of which three-vessel disease accounted for 59.9% (403 cases) and double-vessel disease accounted for 25.4% (171 cases).The target vessel in the bifurcation group was predominantly left anterior descending artery (62.3%, 210 cases), and the target vessel in the non-bifurcation group was more common in the right coronary artery (56%, 188 cases). The target vessel diameter was larger in the bifurcation group (2.91(2.71, 3.24) mm vs 2.80(2.55, 3.13) mm, P<0.001). Most patients used the antegrade technique (88%, 592 cases), and the use of antegrade technique in the bifurcation group (91.9%, 307 cases) was higher than that in the non-bifurcation group (84.8%, 285 cases) (P=0.012). After CTO-PCI, 72.8% (490 cases) of patients achieved successful angiography. A total of 73 patients (10.8%) had perioperative complications, and there was no statistical difference between the two groups. However, the incidence of perioperative myocardial infarction was higher in the bifurcation group (5.9%, 20 cases) than non-bifurcation group (2.7%, 9 cases) (P=0.038). Conclusions: CTO complicated with bifurcation lesions are very common in clinical practice. Most patients with CTO have multiple coronary artery disease at the same time. The target vessel is more common in the left anterior descending artery, and the diameter of the vessel is larger. It is more common to use antergrade technique, accompanied by more perioperative myocardial infarctions.

A nitrate transporter encoded by ZmNPF7.9 is essential for maize seed development

Nitrogen is an essential macronutrient for plants and regulates many aspects of plant growth and development. Nitrate is one of the major forms of nitrogen in plants. However, the role of nitrate uptake and allocation in seed development is not fully understood. Here, we identified the maize (Zea mays) small-kernel mutant zmnpf7.9 and characterized the candidate gene, ZmNPF7.9, which was the same gene as nitrate transport 1.5 (NRT1.5) in maize. This gene is specifically expressed in the basal endosperm transfer layer cells of maize endosperm. Dysfunction of ZmNPF7.9 resulted in delayed endosperm development, abnormal starch deposition and decreased hundred-grain weight. Functional analysis of cRNA-injected Xenopus oocytes showed that ZmNPF7.9 is a low-affinity, pH-dependent bidirectional nitrate transporter. Moreover, the amount of nitrate in mature seeds of the zmnpf7.9 mutant was reduced. These suggest that ZmNPF7.9 is involved in delivering nitrate from maternal tissues to the developing endosperm. Moreover, most of the key genes associated with glycolysis/gluconeogenesis, carbon fixation, carbon metabolism and biosynthesis of amino acids pathways in the zmnpf7.9 mutant were significantly down-regulated. Thus, our results demonstrate that ZmNPF7.9 plays a specific role in seed development and grain weight by regulating nutrition transport and metabolism, which might provide useful information for maize genetic improvement.

[Study of sequential surgical guide assisting full arch immediate implant placement and provisionalization in patients with severe periodontitis]

To explore the technical process and the therapeutic effect of using sequential surgical guide with independent intellectual property rights assisting immediate implantation and restoration of the full arch, with the support from the periodontal splint for mobile supporting teeth, patients with severe periodontitis who planned to undergo immediate full arch implantation were recruited from August 2019 to December 2020 at the Department of Prosthodontics, Department of Periodontology, Department of Implantology and First Clinical Division, Peking University School and Hospital of Stomatology. Through the procedure of collecting preoperative maxillofacial data, making systematic diagnostic design, making periodontal splints fixation, producing surgical guide, and carrying out guided surgery for full arch immediate implantation, eight cases were included. By registering the postoperative cone-beam CT (CBCT) with the preoperative data, the difference between the actual three-dimensional position of the implants and the virtual design was observed, and the accuracy of the implant placement position guided by the sequential guide was statistically analyzed using SPSS 25.0 software. Analysis indicators include coronal and apical global displacement, coronal horizontal and vertical displacement, apical horizontal and vertical displacement, and angular deviation. Results revealed that the 8 patients [2 males and 6 females, aged (49.0±9.3) years (38-65 years)] of recruited cases included 7 cases of maxilla and 1 cases of mandible. A total of 48 implants, of which 44 implants were placed upright and 4 were placed tilted, 16 implants in the anterior region and 32 implants in the posterior region. No guide plate fracture or damage to important anatomical structures were reported. The overall displacement at the coronal point [(0.83±0.48) mm] and the global displacement at the apical point [(1.36±0.57) mm] were within the clinically acceptable safety range, and the horizontal displacement and vertical displacement at the coronal point, horizontal displacement and vertical displacement at the apical point, and the angle deviation of implants axial have no statistic significant difference in the anterior and posterior region (P>0.05). Periodontal splints combined with sequential surgical guides to assist patients with severe periodontitis for immediate full arch implantation and immediate restoration can expand the indications of guide assisted implant surgery. It meets the safety requirements in clinical applications.

The novel E-subgroup pentatricopeptide repeat protein DEK55 is responsible for RNA editing at multiple sites and for the splicing of nad1 and nad4 in maize

BACKGROUND

Pentatricopeptide repeat (PPR) proteins compose a large protein family whose members are involved in both RNA processing in organelles and plant growth. Previous reports have shown that E-subgroup PPR proteins are involved in RNA editing. However, the additional functions and roles of the E-subgroup PPR proteins are unknown.

RESULTS

In this study, we developed and identified a new maize kernel mutant with arrested embryo and endosperm development, i.e., defective kernel (dek) 55 (dek55). Genetic and molecular evidence suggested that the defective kernels resulted from a mononucleotide alteration (C to T) at + 449 bp within the open reading frame (ORF) of Zm00001d014471 (hereafter referred to as DEK55). DEK55 encodes an E-subgroup PPR protein within the mitochondria. Molecular analyses showed that the editing percentage of 24 RNA editing sites decreased and that of seven RNA editing sites increased in dek55 kernels, the sites of which were distributed across 14 mitochondrial gene transcripts. Moreover, the splicing efficiency of nad1 introns 1 and 4 and nad4 intron 1 significantly decreased in dek55 compared with the wild type (WT). These results indicate that DEK55 plays a crucial role in RNA editing at multiple sites as well as in the splicing of nad1 and nad4 introns. Mutation in the DEK55 gene led to the dysfunction of mitochondrial complex I. Moreover, yeast two-hybrid assays showed that DEK55 interacts with two multiple organellar RNA-editing factors (MORFs), i.e., ZmMORF1 (Zm00001d049043) and ZmMORF8 (Zm00001d048291).

CONCLUSIONS

Our results demonstrated that a mutation in the DEK55 gene affects the mitochondrial function essential for maize kernel development. Our results also provide novel insight into the molecular functions of E-subgroup PPR proteins involved in plant organellar RNA processing.

[Effect and mechanism of PRDX1 in epithelial mesenchymal transformationin of gastric cancer cells]

Objective: To explore the effect and mechanism of peroxiredoxin1 (PRDX1) in epithelial mesenchymal transformation (EMT) of gastric cancer cells. Methods: The expression of PRDX1 protein was detected by immunohistochemistry (IHC) in 70 paraffin specimens of cancer and normal mucosa adjacent to gastric cancer, and the relationship between PRDX1 protein and clinicopathological characteristics was analyzed. Then PRDX1-small interfering RNA (siRNA) was synthetized and transfected into human gastric cancer cell line AGS, and 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay was used to test cell proliferation. Transwell chamber assay was employed to test invasion of cells. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot were utilized to test the expressions of PRDX1, E-cadherin, N-cadherin, vimentin, and claudin-1. Results: The positive rate of PRDX1 protein expression in gastric cancer was 81.4%, higher than that in normal mucosa (27.1%, P<0.05). The expression of PRDX1 protein was related to invasive depth and lymph node metastasis of gastric cancer (P<0.05). The expressions of PRDX1 mRNA and protein in AGS cells (2.216±0.445, 1.212±0.136), were higher than those in GES-1 cells (0.342±0.041, 0.328±0.038) (P<0.05). When PRDX1-siRNA was transfected into AGS cells, the proliferation of AGS cells was significantly inhibited (all P<0.05). The invasion and migration rate of AGS cells in the transfection group [(112.00±17.98), (50.87±9.79)%] were significantly lower than those of the negative control group [(192.50±22.02), (83.03±8.67)%] and blank control group [(193.83±22.40), (82.40±7.21)%] (all P<0.05). The expressions of mRNA and protein of N-cadherin, vimentin and claudin-1 decreased, while the expression of E-cadherin increased when PRDX1-siRNA was transfected into AGS cells (P<0.05). Conclusion: PRDX1 may promote the development of gastric cancer by regulating the EMT of gastric cancer cells.

Modified staging system for gastric neuroendocrine carcinoma based on American Joint Committee on Cancer and European Neuroendocrine Tumor Society systems

BACKGROUND

The prognostic values of the AJCC staging system for gastric cancer (GC-AJCC), the AJCC staging system for gastric neuroendocrine tumours (NET-AJCC) and the European Neuroendocrine Tumor Society (ENETS) system for gastric neuroendocrine carcinoma and mixed adenoneuroendocrine carcinoma (MA)NEC remain controversial.

METHODS

Data on patients with (MA)NEC from 21 centres in China were analysed. Different staging systems were evaluated by performing Kaplan-Meier survival analysis and calculating the concordance index (C-index) and Akaike information criterion (AIC). Based on three existing systems, a modified staging system (mTNM) was developed.

RESULTS

A total of 871 patients were included. In the GC-AJCC system, an overlap was noticed for pT2 and pT3 categories. Patients with stage IIIC disease had a similar prognosis to those with stage IV disease. The pT categories of the NET-AJCC system had a lower C-index and higher AIC than those of the other systems. In the ENETS system, there was a low proportion (0·2 per cent) of patients with stage IIIA and a high proportion (67·6 per cent) of stage IIIB disease. The mTNM system adopted the NET-AJCC pT and GC-AJCC pN and pM definitions, and was developed based on the ENETS stage definitions. The proportion of patients in each stage was better distributed and the mTNM system showed improved prognostic performance in predicting overall and disease-free survival.

CONCLUSION

The mTNM system offers more accurate prognostic value for gastric (MA)NEC than the AJCC or ENETS staging systems.

The loss of PTEN expression and microsatellite stability (MSS) were predictors of unfavorable prognosis in gastric cancer (GC)

The predictors for the prognosis of gastric cancer (GC) are not clear. We intended to explore the role of PTEN and microsatellite (MS) in GC, showing their potential as prognostic markers. Primary gastric cancer tissues, adjacent normal tissues, and clinicopathological parameters of 187 patients were collected. The expression level of PTEN and MS status were classified by immunohistochemistry (IHC). The relationship among indicators was compared by the chi-square test. The survival curves were delineated by Kaplan-Meier and tested by Log-rank methods. The impact of multiple factors on prognosis was determined by COX proportional hazards model. Significantly, PTEN expression was associated with lymphatic invasion (p=0.011) and Lauren grade (p=0.015). MS status was associated with differentiation (p=0.006) and Lauren grades (p=0.035). TNM stage was associated with MS status under positive PTEN expression (p=0.014). Patients with microsatellite stability (MSS) had worse median overall survival (OS) than that with microsatellite instability (MSI) (p=0.013). Patients with negative PTEN expression had a worse median OS than that with positive PTEN expression (p<0.001). The tumor subtype of PTEN negative-MSS (p<0.001) and PTEN negative-MSI (p=0.042) were strong predictors of poor survival. Negative PTEN expression and MSS might lead to unfavorable prognosis due to their association with clinicopathological parameters of GC. PTEN expression and MS status could be predictors for the prognosis of GC.

Effects of fine particulate PM2.5 on emphysema of mice via regulating FOXO3A/BIM axis

This study aims to investigate the role of PM_2.5 exposure in inducing apoptosis of alveolar epithelial cells and thereafter emphysema in mice, and the underlying mechanism. PM_2.5 exposure model in mice was constructed. Lung tissues were harvested from healthy mice and model mice for hematoxylin and eosin (H&E) staining. Protein levels of Forkhead box O3 (FOXO3A) and BIM in lung tissues were detected by Western blot. Subsequently, A549 cells were induced with increased doses of PM_2.5, followed by determination of relative levels of FOXO3A, BIM (Bcl-2 interacting mediator of cell death) and clv-caspase3. Apoptosis in PM_2.5-exposed A549 cells was assessed. Chromatin immunoprecipitation (ChIP) assay was conducted to uncover the interaction between FOXO3A and BIM. Finally, regulatory effects of FOXO3A/BIM on apoptosis of A549 cells were determined. PM_2.5 exposure resulted in expansion of alveolar spatial structure and decline of lung function, thus leading to emphysema in mice. Protein levels of FOXO3A and BIM were markedly upregulated in lungs of model mice. Relative levels of FOXO3A, BIM and clv-caspase3 were enhanced in PM_2.5 -exposed A549 cells, which were reversed by transfection of si-FOXO3A. ChIP assay confirmed that FOXO3A was able to regulate BIM transcription through binding its promoter regions. Importantly, regulatory effects of FOXO3A on apoptosis of PM_2.5 -exposed A549 cells were partially reversed by overexpression of BIM. PM_2.5 exposure leads to upregulation of FOXO3A, which triggers BIM transcription, thus inducing apoptosis of alveolar epithelial cells and emphysema in mice.

Symmetry-Protected Topological Triangular Weyl Complex

Weyl points are often believed to appear in pairs with opposite chirality. In this work, we show by first-principles calculations and symmetry analysis that single Weyl phonons with linear dispersion and double Weyl phonons with quadratic dispersion are simultaneously present between two specific phonon branches in realistic materials with trigonal or hexagonal lattices. These phonon Weyl points are guaranteed to locate at high-symmetry points due to the screw rotational symmetry, forming a unique triangular Weyl complex. In sharp contrast to conventional Weyl systems with surface arcs terminated at the projections of a pair of Weyl points with opposite chirality, the phonon surface arcs of the unconventional triangular Weyl complex connect the projections of one double Weyl point and two single Weyl points. Importantly, the phonon surface arcs originating from the triangular Weyl complex are extremely long and span the entire surface Brillouin zone. Furthermore, there are only nontrivial phonon surface states across the isofrequency surface, which facilitates their detection in experiments and further applications. Our work not only offers the promising triangular phonon Weyl complex but also provides guidance for exploring triangular Weyl bosons in both phononic and photonic systems.

DEK43 is a P-type pentatricopeptide repeat (PPR) protein responsible for the Cis-splicing of nad4 in maize mitochondria

Mitochondria, the main energy transducers in plant cells, require the proper assembly of respiratory chain complexes I-V for their function. The NADH dehydrogenase 4 (nad4) gene encodes mitochondrial respiratory chain complex I subunit IV, but the mechanism underlying nad4 transcript splicing is unclear. Here, we report that the P-type pentatricopeptide repeat (PPR) protein DEFECTIVE KERNEL 43 (DEK43) is responsible for cis-splicing of the nad4 transcript in maize. We demonstrate that DEK43 localizes to both the nucleus and mitochondria. The mutation of Dek43 resulted in embryo-lethal and light-colored defective kernels. Among the 22 mitochondrial group II introns, the splicing efficiency of nad4 introns 1 and 3 was reduced by up to 50% compared to the wild type. The levels of complex I and supercomplex I+III₂ were also reduced in dek43. Furthermore, in-gel NADH dehydrogenase assays indicated that the activities of these complexes were significantly reduced in dek43. Further, the mitochondrial ultrastructure was altered in the mutant. Together, our findings indicate that DEK43, a dual-localized PPR protein, plays an important role in maintaining mitochondrial function and maize kernel development.

[Digital evaluation of supracrestal gingival thickness induced by periodontal regenerative and corticotomy surgery in patients with skeletal class Ⅲ malocclusion]

Objective: To establish a quantitative three-dimensional method based on intraoral scan to evaluate the changes of soft tissue, and to evaluate the changes of supracrestal gingival thickness (SGT) in skeletal class Ⅲ patients induced by periodontal regenerative and corticotomy surgery (PRCS). Methods: Twenty-two systematically and periodontally healthy skeletal class Ⅲ patients (4 males and 18 females, aged between 19 and 35 years), who were in need of combined orthodontic-orthognathic treatment and referred to the Department of Periodontology from the Department of Orthodontics and the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from January, 2018 to March, 2019, were collected in the study. The teeth involved were 112 anterior teeth (46 maxillary anterior teeth and 66 mandibular anterior teeth). PRCS in anterior tooth area was conducted before orthodontic decompensation. Probing depth (PD), bleeding index (BI) and keratinized gingiva width (KGW) were recorded before surgery and 6 months post-surgery. The intraoral digital impressions of maxillary and mandibular anterior teeth were obtained by 3-shape intraoral scanner before surgery and 6 months after surgery. The Standard Tessellation Language (STL) files were processed using Geomagic qualify 12.2 software to establish the soft tissue morphological measurement model, and to quantitatively analyze the changes of gingival thickness situated 1 to 2 mm apical to the free gingival margin on the median sagittal measurement plane. Results: Probing depth and bleeding index had no significant difference before and 6 months after operation (P>0.05). KGW in 6-month post-operation group [(5.18±2.32) mm] was significantly higher than that in pre-operation group [(4.22±1.43) mm] (P<0.05). Supracrestal gingival thickness situated 1 to 2 mm apical to the free gingival margin also significantly increased 6 months after surgery (P<0.05). The changes of gingival thickness situated 1 to 2 mm apical to the free gingival margin in the upper anterior area were (0.68±0.56) and (1.00±0.69) mm, respectively. The changes in the lower anterior area were (0.38±0.42) and (0.58±0.45) mm, respectively. The gingival changes of the upper anterior teeth were also significantly higher than those of the lower anterior teeth (P<0.01). Conclusions: The described quantitative measurement based on intraoral scan could be an effective method for quantitative evaluation of the changes of soft tissue. PRCS could safely increase the supracrestal gingival thickness as well as KGW in skeletal class Ⅲ patients who were in need of combined orthodontic-orthognathic treatment.

Pentatricopeptide repeat protein DEK40 is required for mitochondrial function and kernel development in maize

Pentatricopeptide repeat (PPR) proteins are one of the largest protein families, which consists of >400 members in most species. However, the molecular functions of many PPR proteins are still uncharacterized. Here, we isolated a maize mutant, defective kernel 40 (dek40). Positional cloning, and genetic and molecular analyses revealed that DEK40 encodes a new E+ subgroup PPR protein that is localized in the mitochondrion. DEK40 recognizes and directly binds to cox3, nad2, and nad5 transcripts and functions in their processing. In the dek40 mutant, abolishment of the C-to-U editing of cox3-314, nad2-26, and nad5-1916 leads to accumulated reactive oxygen species and promoted programmed cell death in endosperm cells due to the dysfunction of mitochondrial complexes I and IV. Furthermore, RNA sequencing analysis showed that gene expression in some pathways, such as glutathione metabolism and starch biosynthesis, was altered in the dek40 mutant compared with the wild-type control, which might be involved in abnormal development of the maize mutant kernels. Thus, our results provide solid evidence on the molecular mechanism underlying RNA editing by DEK40, and extend our understanding of PPR-E+ type protein in editing functions and kernel development in maize.

[Risk factors of coloanal anastomotic stricture after laparoscopic intersphincteric resection for low rectal cancer]

Objective: To evaluate the risk factors of coloanal anastomotic stricture after laparoscopic intersphincteric resection (Lap-ISR) for patients with low rectal cancer. Methods: A retrospective case-control study was performed to collect clinicopathological data from a prospective database (registration number: ChiCTR-ONC-15007506) at the Department of Colorectal Surgery, the Characteristic Medical center of PLA Rocket Force. From June 2011 to August 2018, a total of 144 consecutive patients with low rectal cancer who underwent Lap-ISR were enrolled in the study. Inclusion criteria: (1) reconstruction of digestive tract by end-to-end hand-made coloanal anastomosis (HCAA); (2) distance from lower tumor margin to anorected sphincter ring < 1 cm and distance from lower tumor margin to intersphincteric groove ≥ 1 cm; (3) T1-3 stage tumor with expected negative circumferential resection margin evaluated by preoperative MRI or 3D endoanal ultrasound; (4) rectal cancer confirmed as well- or moderately-differentiated adenocarcinoma; (5) preoperative Wexner incontinence score >10 points. Exclusion criteria: (1) follow-up period less than 3 months; (2) multiple primary cancers; (3) undergoing colonic J-pouch, coloplasty or reconstruction of end-to-side coloanal anastomosis; (4) death within perioperative period (within 3 months after surgery). Coloanal anastomotic stricture was diagnosed if the index finger or 12 mm electronic colonoscope had obvious resistance through the anastomosis or new rectum, or could not pass, accompanied by clinical symptoms such as difficult defecation and anal incontinence. Degree of anastomotic stricture was divided into 3 grades: grade A required anal enlargement, laxative or enema to assist defecation without active surgical treatment; grade B required surgery or endoscopic intervention; grade C required definitive ostomy, including unreducible preventive ileostomy or permanent colostomy. Univariate and multivariate analysis were used to evaluate the effects of 28 variables, including baseline data (age, gender, body mass index, neoadjuvant therapy, etc.), tumor-related factors (distance between tumor low margin and anal edge, maximum diameter of tumor, TNM staging, etc.), surgery-related factors (operation time, intraoperative blood loss, ISR procedure, anastomotic height, etc.) and anastomotic leakage, on the postoperative coloanal anastomotic stricture. Univariate analysis used χ(2) test or Fisher's exact test, then factors with P<0.05 were further included in multivariate analysis using logistic regression. Results: A total of 144 patients were enrolled in the study, including 90 males and 54 females with a median age of 59 years and median BMI of 24.88 kg/m(2). R0 resection rate was 96.5% (139/144). Median tumor distal resection margin was 1.5 (0.5 to 3.0) cm. Median follow-up was 31.5 (4 to 86) months. Coloanal anastomotic stricture was observed in 19 patients (13.2%), including 3 cases (2.1%) of grade A, 9 cases (6.2%) of grade B, and 7 cases (4.9%) of grade C. The median interval from the initial surgery to diagnosis of anastomotic stricture was 7 (1 to 31) months. Univariate analysis showed that male (χ(2)=6.795, P=0.009), radiotherapy (χ(2)=13.330, P=0.001), operation type of ISR (χ(2)=7.996, P=0.013), and anastomotic leakage (χ(2)=10.198, P=0.004) were associated with the postoperative coloanal anastomotic stricture. Multivariate analysis further indicated that male (OR=5.975, 95% CI: 1.209-29.534, P=0.028), postoperative radiotherapy (OR=8.748, 95% CI: 2.397-31.929, P=0.001), and anastomotic leakage (OR=6.313, 95% CI: 1.834-21.734, P=0.003) were independent risk factor of postoperative coloanal anastomotic stricture. Conclusion: For male patients, or patients with postoperative radiotherapy or anastomotic leakage, close follow-up should be carried out to prevent postoperative coloanal anastomotic stricture following Lap-ISR.

Symmetry-Protected Ideal Type-II Weyl Phonons in CdTe

Nontrivial low-energy excitations of crystalline solids have insightfully strengthened understanding of elementary particles in quantum field theory. Usually, topological quasiparticles are mainly focused on fermions in topological semimetals. We alternatively show by first-principles calculations and symmetry analysis that ideal type-II Weyl phonons are present in zinc-blende cadmium telluride, a well-known II-VI semiconductor. Importantly, these type-II Weyl phonons originate from the inversion between the longitudinal acoustic and transverse optical branches. Symmetry guarantees that the type-II Weyl points lie along the high-symmetry lines at the boundaries of the Brillouin zone even with a breaking of inversion symmetry, exhibiting the robustness of protected phonon features. The nontrivial phonon surface states and surface arcs projected on the semifinite (001) and (111) surfaces are investigated. The phonon surface arcs connecting the Weyl points with opposite chirality, guaranteed to be very long, are clearly visible. We not only offer a promising candidate for studying type-II Weyl phonons but also provide a route to realize symmetry-protected nontrivial phonons and related applications in realistic materials.

The expression of prostaglandins-related genes in erythrocytes of broiler chicken responds to thiram-induced tibial dyschondroplasia and recombinant glutathione-S-transferase A3 protein

Tibial dyschondroplasia (TD) is a type of bone deformity found in fast-growing chickens, which induce inflammatory responses. Prostaglandins (PGs) implicate in bone formation and bone resorption, associated with inflammation in an autocrine/paracrine manner. This study used qRT-PCR and immunohistochemistry analysis to identify the expression patterns of PG-related genes in the erythrocytes of broiler chickens and explore the effects of thiram-induced TD and the recombinant glutathione-S-transferase A3 (rGSTA3) protein on the expression of PG-related genes: GSTA3, cyclooxygenase 2 (COX-2), prostaglandin D2 synthase (PTGDS), prostaglandin E synthase (PTGES), prostaglandin E2 receptor (PTGER) 3, PTGER4 and prostaglandin reductase 1 (PTGR1). Interestingly, the results showed that these seven PG-related genes expression was identified in the erythrocytes of broiler chicken, and thiram-induced TD suppressed the expression of these PG-related genes in the initial stage of TD and promoted their expression in TD recovery. These findings demonstrated that the immunoregulatory function of erythrocytes can be inhibited in the early stage of TD and promoted in the recovery stage by modulating the expression of PG-related genes. Further, the rGSTA3 protein can modulate the expression of PG-related genes in erythrocytes and participate in the recovery of TD.

[A prognostic scoring scale for adult patients with supratentorial primary anaplastic gliomas]

Objective: This study explored the prognostic factors of patients with supratentorial anaplastic gliomas and tried to propose a prognostic scoring scale with aim to provide theoretical reference for clinical treatment. Methods: The clinical data of 198 patients surgically treated for primary anaplastic glioma in Henan Provincial People's Hospital between Jan 2009 and Jan 2018 were reviewed. Univariate and multivariate analyses were used to identify prognostic factors with methods of Kaplan-Meier plot and Cox proportional hazard model, respectively. Based on the prognostic factors, a scoring scale was thereby proposed. Results: Univariate analysis results showed age, tumor location, tumor diameter, preoperative KPS, extent of resection, radiotherapy, chemotherapy, pathology with oligodendroglial components, 1p/19q, IDH, MGMT were significantly correlated with survival (P<0.05). Multivariate analysis results showed age ≥45 years old, tumor diameter ≥6 cm, preoperative KPS<70, without radiotherapy, 1p/19q intact, MGMT promoter unmethylation were independent prognostic risk factors (P<0.05). Patients were scored with 0-6 points based on the formulation that each independent prognostic risk factor was assigned with 1 point. Then patients were further grouped according to the score. Those with less than 2 points were low-risk group, equal to 2 points were medium-risk group, equal to 3 points were high-risk group, more than or equal to 4 points were extremely high-risk group. There were significant differences in survival between the different groups (P<0.000 1). Conclusions: The higher score, the shorter survival time. This prognostic scoring scale can provide a theoretical basis for the prognosis estimation of patients with anaplastic glioma and help to carry out personalized clinical treatment.

Robust Twin Pairs of Weyl Fermions in Ferromagnetic Oxides

The ferromagnetic Weyl semimetals with inversion symmetry usually possess odd pairs of Weyl fermions. Here, we present an inversion eigenvalue argument to dictate the existence of even pairs of ferromagnetic Weyl fermions. We show, by a combination of first-principles calculations and symmetry analyses, that this exotic topological feature can be verified in ferromagnetic oxides in different space groups. In particular, a realistic candidate, i.e., hollandite RbCr_{4}O_{8} with a high Curie temperature (∼295  K), hosts intriguing twin pairs of Weyl fermions, which are robustly stable against perturbations. Moreover, our effective model and symmetry analysis show that the twin pairs of Weyl fermions originate from a mirrored nodal ring pair. The nontrivial surface states and Fermi arcs of RbCr_{4}O_{8} are clearly visible, further revealing the topological features. This work strengthens the understanding of the parity analysis in exploring ferromagnetic topological materials with unconventional fermionic excitations.

[Evaluation of the effect of electrical stimulation combined with biofeedback therapy for postpartum pelvic organ prolapse: a static and dynamic magnetic resonance imaging study]

Objective: To explore the clinical value of static and dynamic magnetic resonance imaging (MRI) in evaluating the effect of electrical stimulation combined with biofeedback in the treatment of pelvic organ prolapse postpartum. Methods: A total of 50 primiparas diagnosed as pelvic organ prolapse postpartum from February 2016 to November 2017 were randomly divided into treatment group (24 cases) and control group (26 cases). The control group recovered spontaneously, and the treatment group received electric stimulation combined with biofeedback therapy (6 weeks). All subjects underwent static and dynamic MRI before and after treatment. The thickness of bilateral puborectal muscles, levator ani hiatus area (LHA), H line, M line and levator ani plate angle (LPA) were respectively measured in rest state and strain state at 42 days and 12 weeks postpartum, and the differences of parameters were compared between two groups. Results: (1) Compared with 42 days postpartum, the effective rate of pelvic organ prolapse was 15.4% (4/26) in the control group and 62.5% (15/24) in the treatment group, which was significantly higher than that of the control group (P<0.01). (2) Compared with 42 days postpartum, the thickness of bilateral puborectal muscles in the treatment group increased at 12 weeks postpartum, while that of the H line, LHA, M line and LPA in strain state decreased. (3) At 12 weeks postpartum, the thickness of the bilateral puborectal muscle in the treatment group was greater, and LHA, M line, and LPA in strain state were less than that in the control group (all P<0.05). Conclusion: Electrical stimulation combined with biofeedback therapy can improve pelvic organ prolapse due to vaginal delivery, and the static and dynamic MRI can objectively evaluate the effect of pelvic floor rehabilitation therapy on improving the pelvic floor supporting structure and function, providing an important support and guidance for restoration of postpartum pelvic organ prolapse.

[Quantitative three-dimensional methodology based on intraoral scan to assess the soft tissue contour alterations following single immediate implant and immediate provisionalization in maxillary central incisor: a 1-year prospective study]

Objective: To establish a quantitative three-dimensional method based on intraoral scan and apply it to evaluation of the facial soft tissue contour alterations following single immediate implant and immediate provisionalization (IIPP) in central incisor via intraoral scanning. Methods: This study was a prospective clinical study. The trial was conducted at Department of Implantology, Peking University School and Hospital of Stomatology, from January 2016 to September 2017. Twenty-nine eligible consecutive patients (15 women, 14 men) with a mean age of (34.3±12.0) were included and received immediate replacement of the failure maxillary single central incisor. A screw-retained immediate restoration was delivered for each patient. At 6-month follow-up, impression was taken and a screw-retained permanent restoration was performed for each patient. The anterior maxillary region was scanned by an intraoral scanning system at pre-surgery and 1-year follow-up. The Standard Tessellation Language (STL) files were output to a dedicated software and superimposed. Mid-facial recession and gingival zenith symmetry at 1-year follow-up were measured in the digital models. Three-dimensional configurations of the contour change volume were calculated and reconstructed for visual analysis. Furthermore, the following parameters were used to analyze the reconstructed volume: mean contour change in thickness (△d), mesio-distal width (D(W)), coronal-apical height (D(H)), contour change at 0, 1, 2, 3, 4, 5 mm apical to the free gingival margin on the implant site. Results: Twenty-seven out of twenty-nine enrolled patients were finally available for analysis. At 1-year follow-up, the mid-facial mucosa level at implant site was (0.23±0.39) mm apical to the gingival zenith of the contralateral tooth. In general, a contour collapse was found in every patient. △d, D(W) and D(H) of the collapsed volume were (0.62±0.22), (11.03±1.74) and (6.82±1.52) mm, respectively. Contour change at 0, 1, 2, 3, 4, 5 mm apical to the free gingival margin on the implant site were (0.54±0.48), (0.87±0.62), (1.03±0.46), (0.96±0.52), (0.90±0.52), (0.89±0.57) mm. Conclusions: The described quantitative measurement based on intraoral scan can be an effective method for assessment of soft tissue contour changes. At 1 year following single IIPP treatment in maxillary incisor, free gingival margin is stable, with only mild recession. The mean level of the facial soft tissue contour collapse is 0.62 mm.

[An study on the incidence of heat stroke and explore it's prediction model in Pudong New Area of Shanghai from 2013-2017]

Objective: To know the incidence of heat stroke and explore it's prediction model in Pudong New Area of Shanghai. Methods: An epidemiological investigation was conducted on heat stroke cases in Pudong New Area of Shanghai from 2013 to 2017. Daily temperature data during this period were collected to explore it's influence. Results: 246 heat stroke cases were reported and investigated, 70.3% (173/246) of them were male. 170 cases are severe heat stroke, accounting for 69.1%. 28 patients died, accounting for 11.4% of all cases of heat stroke, and 16.5% (28/170) of severe heat stroke cases. Thermoplegia (56.5%, 96/170) was the most popular type among severe heat stroke cases. Heat prostration, heat cramps and mixed type account for 17.1% (29/170) , 12.4% (21/170) and 14.0% (24/170) respectively. Scatter plot and linear regression demonstrated that there was a significant linear relation between number of high temperature days and number of heat stroke cases (P<0.01) . And the prediction model is: Predictive number of annual heat stroke cases=β×Number of annual high temperature days+Intercept. Leave-one-out cross validation result shows that the predictive number of annual heat stroke cases from 2013 to 2017 were 85.7%, 90.9%, 83.3%, 91.9 and 84.3% respectively. Conclusion: There was a significant linear relation between number of high temperature days and number of heat stroke cases in Pudong New Area. The related work arrangement for heat stroke prevention could be well planed according to the prediction model.

[Advances in determination of median sagittal plane of facial soft tissue]

Facial symmetry is a crucial component of human facial esthetics. Along with the increasing pursuit of aesthetic, in recent years, more and more researchers have focused on facial asymmetry assessment, of which determining the facial median sagittal plane is the first and most important step, and it will directly affect the accuracy of asymmetry evaluation and clinical treatment outcome. Limited by technical means, the earlier studies of facial soft tissue asymmetry assessment were mainly based on midline from two-dimensional (2D) images. Along with the development of three-dimensional (3D) measurement and data analysis techniques, new methods such as 3D landmark-based method and mirror-original alignment method have become main trend nowadays. This article systematically reviews the methods of determination of median sagittal plane of facial soft tissue, elaborates the developments and the latest research progress in this field, and discusses the advantages and limitations of each method in order to provide reference for clinical application.

[Effects of benzo(a)pyrene on expressions of insulin-degrading enzyme and neprilysin in neuroglia cells]

OBJECTIVE

To investigate effects of benzo(a)pyrene (BaP) on expressions of insulin-degrading enzyme (IDE) and neprilysin (NEP) which have the ability to degrade β-amyloid (Aβ) in neuroglia cells.

METHODS

Primary mix-neuroglia cells were cultured from newborn SD rats. After exposure to BaP, Aβ_1-42 oligomer or Aβ_1-42 fiber individually or jointly for 24 h, the cell survival rate was measured by cell counting kit-8 (CCK-8). Afterwards, the primary mix-neuroglia cells were divided randomly into six groups: Control group, BaP group (2.00 μmol/L), Aβ_1-42 oligomer group (20.00 mg/L), BaP plus Aβ_1-42 oligomer group, Aβ_1-42 fiber group (20.00 mg/L) and BaP plus Aβ_1-42 fiber group, of which BaP was pretreated for 12 h followed by cotreatment with different aggregated Aβ_1-42. The expressions of IDE and NEP were measured by quantitative real-time polymerase chain reaction (qRT-PCR) for mRNA level and Western blotting for protein level.

RESULTS

The cell survival rate showed no significant differences after treatment with BaP (≤20.00 μmol/L), Aβ_1-42 oligomer (20.00, 40.00 mg/L), Aβ_1-42 fiber (20.00, 40.00 mg/L) or cotreatment with BaP and Aβ_1-42 oligomer or BaP and Aβ_1-42 fiber. Compared with the control group, expressions of IDE and NEP in BaP-treated alone group had no obvious change; however, exposure to Aβ_1-42 oligomer alone significantly increased the mRNA and protein level of IDE (P<0.05), and the BaP pretreatment could significantly inhibit the up-regulated expressions of IDE by Aβ_1-42 oligomer (P<0.05); on the other hand, exposure either to Aβ_1-42 fiber alone or under the BaP pretreatment did not change the mRNA and protein level of IDE and NEP obviously.

CONCLUSION

On the premise of no significant change of cell survival rate, BaP pretreatment inhibited the up-regulated expressions of IDE in primary mixed neuroglia cells under cotreatment with Aβ oligomer, indicating that BaP may disturb degradation of Aβ oligomer and cause deposition of β-amyloid and further induce cognitive decline and acceleration of Alzheimer.

[Understanding chair-side digital technology for stomatology from an engineering viewpoint]

In recent years with the rapid development of digital technology for stomatology, the application field, application model, technical features and technical connotation of the chair-side digital technology has got development and change. The open modular system has gradually replaced the traditional closed system, and the application field of digital technology is no longer limited to chair-side dental restoration, it also has been extend to various kinds of chair-side digital treatment-assisted technology. In this paper, from the engineering point of view, the up to date general connotation of chair-side digital technology was explained, the characteristics and the development of each unit in chair-side digital technology were analyzed, and the application pattern and the localization status were also discussed in this paper. The aim of this paper was to introduce the trend of chair-side digital technological to readers and to better guide clinical application.

[Preliminary study on the accuracy of infrabony root surface area of single-root teeth by periapical films]

OBJECTIVE

To explore the accuracy of periapical film in evaluating the infrabone root surface area of single-root teeth with different types of resorption of the alveolar bone.

METHODS

In this study, the medical records and imaging data of patients in Department of Periodontology of Peking University Hospital of Stomatology from January 2014 to December 2016 were retrospectively analysed. The involved teeth were divided into two groups: horizontal bone loss group and vertical bone loss group. Digital three-dimensional models of teeth were segmented from cone beam computed tomography (CBCT) data, and the percentage of the infrabone root surface area was measured. While the percentage of the residual alveolar bone was measured on the periapical films. The correlation of the two percentages were analyzed, and the differences between the two percentages of each group were compared.

RESULTS

Thirty-two patients and 79 single-root teeth were involved totally, in whom there were 25 men and 7 women, aged 26-60 years, and of which there were 41 teeth in the horizontal bone loss group and 38 teeth in the vertical bone loss group. The remaining alveolar bone height percentages were 45.13%-90.39% on the periapical films, and at the same time, the infrabone root surface area percentages were 36.27%-93.03% on CBCT. The residual alveolar bone height percentage of the horizontal bone loss group was not subject to normal distribution, so the residual alveolar bone height percentage and the infrabone root surface area percentage were analyzed by Wilcoxon matched pair rank test (P=0.382), and the result showed no statistically significant difference. The mean value of difference value of the two measurements was 0, and the consistency limit of 95 % was -9.7%-9.8%, between the clinical consistency limit (-15%-15%).The residual alveolar bone height percentage and the infrabone root surface area percentage of the vertical bone loss group were analyzed by paired T test (P< 0.001), and the result showed statistically significant difference. The mean value of difference value of the two measurements was 7.2 %, and the consistency limit of 95% was -13.1%-27.5%, beyond clinical consistency limit (-15%-15%).

CONCLUSION

For the teeth with horizontal bone loss, the proximal residual alveo-lar bone height reflected on the periapical films could show the infrabone root surface area relatively accurately. For the teeth with vertical bone loss, the periapical films could not show the degree of periodontal tissue loss accurately, and it would underestimate the extent of bone destruction usually, so CBCT might be taken to show the bone destruction condition of this type of teeth if necessary.

[Application of digital design of orthodontic-prosthodontic multidisciplinary treatment plan in esthetic rehabilitation of anterior teeth]

OBJECTIVE

To develop a digital workflow of orthodontic-prosthodontic multidisciplinary treatment plan which can be applied in complicated anterior teeth esthetic rehabilitation, in order to enhance the efficiency of communication between dentists and patients, and improve the predictability of treatment outcome.

METHODS

Twenty patients with the potential needs of orthodontic-prosthodontic multidisciplinary treatment to solve their complicated esthetic problems in anterior teeth were recruited in this study. Digital models of patients' both dental arches and soft tissues were captured using intra oral scanner. Direct prosthodontic (DP) treatment plan and orthodontic-prosthodontic (OP) treatment plan were carried out for each patient. For DP treatment plans, digital wax-up models were directly designed on original digital models using prosthodontic design system. For OP treatment plans, virtual-setups were performed using orthodontic analyze system according to orthodontic and esthetic criteria and imported to prosthodontic design system to finalize the digital wax-up models. These two treatment plans were shown to the patients and demonstrated elaborately. Each patient rated two treatment plans using visual analogue scales and the medians of scores of two treatment plans were analyzed using signed Wilcoxon test. Having taken into consideration various related factors, including time, costs of treatment, each patient chose a specific treatment plan. For the patients chose DP treatment plans, digital wax-up models were exported and printed into resin diagnostic models which would be utilized in the prosthodontic treatment process. For the patients chose OP treatment plans, virtual-setups were used to fabricate aligners or indirect bonding templates and digital wax-up models were also exported and printed into resin diagnostic models for prosthodontic treatment after orthodontic treatment completed.

RESULTS

The medians of scores of DP treatment plan and OP treatment plan were calculated and analyzed by IBM SPSS 20. The median of scores of DP treatment plan was 8.4, the minimum value was 6.9 and the maximum value was 9.3. The median of scores of OP treatment plan was 9.0, the minimum value was 7.9 and the maximum value was 9.6. The median of scores of OP was significantly higher than that of DP (Z=-3.23, P<0.01). Finally, 12 patients chose OP treatment plans and 8 patients chose DP treatment plans.

CONCLUSION

For cases with complex esthetic problems in anterior teeth, a digital workflow can demonstrate final treatment outcome and help patients make suitable treatment decisions. In our study, the orthodontic-prosthodontic multidisciplinary treatment plan is feasible which can provide predictions of treatment outcome and improve esthetic outcome with patients' satisfaction.

Robust generation of entangled state via ground-state antiblockade of Rydberg atoms

We propose a mechanism of ground-state antiblockade of Rydberg atoms, which is then exploited to prepare two-atom entangled state via three different kinds of pulses. First we use the pulses in the form of sin2 and cos2 functions and obtain a maximally entangled state at an accurate interaction time. Then the method of stimulated Raman adiabatic passage (STIRAP) is adopted for the entanglement generation, which is immune to the fluctuations of revelent parameters but requires a long time. Finally we capitalize the advantages of the former two methods and employ shortcuts to adiabatic passage (STAP) to generate the maximal entanglement. The strictly numerical simulation reveals that the current scheme is robust against spontaneous emission of atoms due to the virtual excitation of Rydberg states, and all of the above methods favor a high fidelity with the present experimental technology.

[Quantitative evaluation of printing accuracy and tissue surface adaptation of mandibular complete denture polylactic acid pattern fabricated by fused deposition modeling technology]

Objective: To quantitatively evaluate the adaptation of polylactic acid (PLA) pattern of mandibular complete denture fabricated by fused deposition modeling (FDM) technology. Methods: A mandibular complete denture digital model was designed through a complete denture design software based on a pair of standard maxillomandibular edentulous plaster model and their occlusion bases. Ten PLA mandibular complete dentures were printed with a FDM machine. The dentures were scanned with and without the plaster model using a three-dimensional (3D) scanner. In Geomagic software, the scanning data of printed dentures were registered to its computer aided design (CAD) data, and the printing error was analyzed using the multipoint registration command. For quantitatively evaluating the adaptation of the denture, the data of plaster model and PLA denture were registered to the whole data of denture located in the plaster model using the best-fit alignment command, the 3D deviation of the plaster model and tissue surface of the denture represent the space between them. The overall area was separated into three parts: primary stress-bearing area, secondary stress-bearing area and border seal area, and the average deviations of these three parts were measured. The values were analyzed using analysis of variance. Results: Compared with the CAD data, the printing error was (0.013±0.004) mm. The overall 3D deviation between PLA denture and plaster model was (0.164±0.033) mm, in which the primary stress-bearing area was (0.165± 0.045) mm, the secondary stress-bearing area was (0.153 ± 0.027) mm, the border seal area was (0.186 ± 0.043) mm. These showed a good fit in the majority parts of the FDM denture to the plaster model. No statistically significant difference was observed between the three areas (F=1.857, P=0.175>0.05). Conclusions: Combined with the 3D scanning, CAD and FDM technology, a FDM 3D printing process of complete denture for injection moulding can be established. As a result, high efficiency and low cost can be used to print out the complete denture, to lay the basis for further clinical applications.

[Three-dimensional data fusion method for tooth crown and root based on curvature continuity algorithm]

OBJECTIVE

To explore a three-dimensional (3D) data fusion and integration method of optical scanning tooth crowns and cone beam CT (CBCT) reconstructing tooth roots for their natural transition in the 3D profile.

METHODS

One mild dental crowding case was chosen from orthodontics clinics with full denture. The CBCT data were acquired to reconstruct the dental model with tooth roots by Mimics 17.0 medical imaging software, and the optical impression was taken to obtain the dentition model with high precision physiological contour of crowns by Smart Optics dental scanner. The two models were doing 3D registration based on their common part of the crowns' shape in Geomagic Studio 2012 reverse engineering software. The model coordinate system was established by defining the occlusal plane. crown-gingiva boundary was extracted from optical scanning model manually, then crown-root boundary was generated by offsetting and projecting crown-gingiva boundary to the root model. After trimming the crown and root models, the 3D fusion model with physiological contour crown and nature root was formed by curvature continuity filling algorithm finally. In the study, 10 patients with dentition mild crowded from the oral clinics were followed up with this method to obtain 3D crown and root fusion models, and 10 high qualification doctors were invited to do subjective evaluation of these fusion models.

RESULTS

This study based on commercial software platform, preliminarily realized the 3D data fusion and integration method of optical scanning tooth crowns and CBCT tooth roots with a curvature continuous shape transition. The 10 patients' 3D crown and root fusion models were constructed successfully by the method, and the average score of the doctors' subjective evaluation for these 10 models was 8.6 points (0-10 points). which meant that all the fusion models could basically meet the need of the oral clinics, and also showed the method in our study was feasible and efficient in orthodontics study and clinics.

CONCLUSION

The method of this study for 3D crown and root data fusion could obtain an integrate tooth or dental model more close to the nature shape. CBCT model calibration may probably improve the precision of the fusion model. The adaptation of this method for severe dentition crowding and micromaxillary deformity needs further research.

[Image features and clinical significance of pneumoconiosis with large shadow]

OBJECTIVE

To investigate the image features, categories, and clinical significances of Pneumoconiosis Ш with large shadow.

METHODS

The research is based on the analysis of image features of 168 pneumoconiosis Ш patients who are directly diagnosed by qualified medical professionals in our institution. These image features are large shadows bigger than 2 cm×1 cm which can be observed by high kilovolt chest radiographs, DR chest radiography and chest CT scan.

RESULTS

Large shadows bigger than 2×1 cm show noticeable imaging characteristics, like distribution of superior and middle lung regions (95.2%) , irregular shapes (97.6%) , splayed or sausage like changes on both sides perpendicular with ribs (89.2%) , small shadows of pneumoconiosis (98.8%) , and convergence of large shadow to hilum or mediastinal (53.6%). CT scan is significantly better than DR radiography on detection rate of focal emphysema, focal cavities and swollen lymph node of mediastinal.

CONCLUSION

Combining the image features of high kilovolt chest radiographs, DR chest radiographs and CT scan are the main methods to identify the shadows, and thus direct diagnose pneumoconiosis Ш; CT scan plays an important role in differential diagnosis.