Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

[Automated cephalometric landmark identification and location based on convolutional neural network]

Objective: To develop an automated landmark location system applicable to the case of landmark missing. Methods: Four and eighty-one lateral cephalograms, which contained 240 males and 241 females, with an average age of (24.5±5.6) years, taken from January 2015 to January 2021 in the Department of Orthodontics, Capital Medical University School of Stomatology, and met the inclusion criteria were collected. Five postgraduate orthodontic students were the annotators to manually locate 61 possible landmarks in 481 lateral cephalograms. Two assistant professors in the department as reviewers performed calibration. Two professors as arbitrators, made final decision. Data sets were established (341 were used as training set, 40 as validation set, and 100 as test set). In this paper, an automatic landmarks identification and location model based on convolutional neural networks (CNN), CephaNET, was developed. The model was trained by feeding the original image into the feature extraction module and convolutional pose machine (CPM) module to locate landmarks with high accuracy using deep supervision. Training set was enhanced to 1 684 images by histogram equalization, cropping, and adjustment of brightness. The model was trained to compare the Gaussian heat maps output from the network with the set threshold to identify landmark missing cases. Test set of 100 lateral cephalograms was used to test the accuracy of the model. The evaluation criteria used were success detection rate of missing landmark, mean radial error (MRE) and success detection rate (SDR) in the range of 2.0, 2.5, 3.0, 3.5 and 4.0 mm. Results: The model identified and located 61 commonly used landmarks in 0.13 seconds on average. It had an average accuracy of 93.5% in identifying missing landmarks. The MRE of our testing set was (1.19±0.91) mm. SDR of 2.0, 2.5, 3.0, 3.5 and 4.0 mm were 85.4%, 90.2%, 93.5%, 95.4%, 97.0% respectively. Conclusions: The model proposed in this paper could adapt to the absence of landmark in lateral cephalograms and locate 61 commonly used landmarks with high accuracy to meet the requirements of different cephalometric analysis methods.

[Technical specification for orthodontic transmission straight wire technique]

Malocclusion is an oral disease with a high prevalence. The goal of orthodontic treatment is health, aesthetics, function and stability. The transmission straight wire appliance and technique is an innovative orthodontic system with independent intellectual property rights invented by Professor Jiuxiang Lin's team based on decades of clinical experience, which provides a new solution for the non-surgical correction of skeletal malocclusions, especially class Ⅲ malocclusion, and it is also a good carrier for the implementation of the concept of healthy orthodontics. Due to the lack of guidelines, how to implement standardized application of transmission straight wire technique remains a problem to be solved. This technical specification was formed by combining the guidance from Professor Jiuxiang Lin and joint revision by a number of authoritative experts from the Orthodontic Special Committee, Chinese Stomatological Association, with reference to relevant literatures, and combined with abundant clinical experience of many experts. This specification aims to provide reference to standardize the clinical application of transmission straight wire technique, so as to reduce the risk and complications, and finally to improve the clinical application level of this technique.

Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

[Association between periconceptional supplementation of folic acid or multiple-micronutrients containing folic acid and preterm delivery in women]

OBJECTIVE

To explore the association between periconceptional supplementation of folic acid or multiple-micronutrients containing folic acid(MMFA) and risk of preterm delivery in women with natural conception, singleton pregnancy and vaginal delivery.

METHODS

A retrospective cohort study was performed based on the prenatal health care system and hospital information system of Tongzhou Maternal and Child Health Hospital of Beijing and the women who had their prenatal care in the hospital from January 2015 to December 2018 were included. The information of 16 332 women who conceived naturally, had a singleton pregnancy, and delivered vaginally was collected. Compliance scores were constructed based on the time of initiation and the frequency of taking nutritional supplements. The association between maternal periconceptional micronutrient supplementation, including pure folic acid (FA) pills or MMFA and the rate of preterm delivery was evaluated using Logistic regression models.

RESULTS

The preterm delivery rate (gestational week < 37 weeks) of the study population was 3.8%, and the mean (standard deviation) of gestational age was (38.98±1.37) weeks. A total of 6 174 (37.8%) women took FA during the periconceptional period, 8 646 (52.9%) women took MMFA, and 1 512 (9.3%) women did not take any nutritional supplements. The association between periconceptional supplementation of FA or MMFA and risk of preterm delivery in women was not statistically significant [adjusted odds ratio (aOR)=1.01, 95%CI: 0.74-1.37]. The associations with preterm birth were not statistically significant in further analysis by the type of nutritional supplements, time of initiation, and the frequency of supplementation. In addition, the association between the compliance score of taking supplements and the rate of preterm delivery was not statistically significant, either.

CONCLUSION

This study did not find an association between the risk of preterm delivery and the use of FA or MMFA during the periconcep-tional period in women with natural conception, singleton pregnancy, and vaginal delivery. In the future, multicenter studies with large-scale prospective cohort or population-based randomized controlled trials are warranted to confirm the association between taking FA or MMFA during the periconceptional period and preterm delivery among women.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

[Research on multi-class orthodontic image recognition system based on deep learning network model]

Objective: To develop a multi-classification orthodontic image recognition system using the SqueezeNet deep learning model for automatic classification of orthodontic image data. Methods: A total of 35 000 clinical orthodontic images were collected in the Department of Orthodontics, Capital Medical University School of Stomatology, from October to November 2020 and June to July 2021. The images were from 490 orthodontic patients with a male-to-female ratio of 49∶51 and the age range of 4 to 45 years. After data cleaning based on inclusion and exclusion criteria, the final image dataset included 17 453 face images (frontal, smiling, 90° right, 90° left, 45° right, and 45° left), 8 026 intraoral images [frontal occlusion, right occlusion, left occlusion, upper occlusal view (original and flipped), lower occlusal view (original and flipped) and coverage of occlusal relationship], 4 115 X-ray images [lateral skull X-ray from the left side, lateral skull X-ray from the right side, frontal skull X-ray, cone-beam CT (CBCT), and wrist bone X-ray] and 684 other non-orthodontic images. A labeling team composed of orthodontic doctoral students, associate professors, and professors used image labeling tools to classify the orthodontic images into 20 categories, including 6 face image categories, 8 intraoral image categories, 5 X-ray image categories, and other images. The data for each label were randomly divided into training, validation, and testing sets in an 8∶1∶1 ratio using the random function in the Python programming language. The improved SqueezeNet deep learning model was used for training, and 13 000 natural images from the ImageNet open-source dataset were used as additional non-orthodontic images for algorithm optimization of anomaly data processing. A multi-classification orthodontic image recognition system based on deep learning models was constructed. The accuracy of the orthodontic image classification was evaluated using precision, recall, F1 score, and confusion matrix based on the prediction results of the test set. The reliability of the model's image classification judgment logic was verified using the gradient-weighted class activation mapping (Grad-CAM) method to generate heat maps. Results: After data cleaning and labeling, a total of 30 278 orthodontic images were included in the dataset. The test set classification results showed that the precision, recall, and F1 scores of most classification labels were 100%, with only 5 misclassified images out of 3 047, resulting in a system accuracy of 99.84%(3 042/3 047). The precision of anomaly data processing was 100% (10 500/10 500). The heat map showed that the judgment basis of the SqueezeNet deep learning model in the image classification process was basically consistent with that of humans. Conclusions: This study developed a multi-classification orthodontic image recognition system for automatic classification of 20 types of orthodontic images based on the improved SqueezeNet deep learning model. The system exhibitted good accuracy in orthodontic image classification.

[Ability and inability of artificial intelligence in orthodontics]

With the development of artificial intelligence (AI) technology, it has a wide range of explorations in orthodontics. AI has greater application prospects in precise measurement, multidimensional diagnosis, treatment planning and efficacy prediction. At the same time, there are certain limitations in the application of AI, such as risks caused by individual variability, black box properties and unclear delineation of medical responsibilities. This paper summarized the history and current status of AI applications in orthodontics and discussed future development trends, to provide reference for clinical orthodontics.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

[Timely and appropriately performing early orthodontic treatment]

In recent years, the early orthodontic treatment of malocclusion has become a hot issue in the field of orthodontics. Some new phenomena and new problems that have emerged require in-depth analysis and discussion, and need to be given correct guidance and norms. Malocclusion refers to the deformities of teeth, jaws, and craniofacial bones caused by genetic and environmental factors during growth and development. Based on the accurate judgment of the etiology and diagnosis, choosing the right time and suitable indications, with the advantage of growth and development, the most suitable appliance can be selected in the early stage of malocclusion to fix malocclusion, and to effectively prevent and block the formation and development of malocclusion. This article will discuss how to timely and appropriately carry out the early prevention and treatment of malocclusion with six aspects, including methods of performing early orthodontic treatment, the basis and guarantee of early orthodontic treatment, correctly understanding early orthodontic treatment, the issues that should be paid attention to in carrying out early orthodontic treatment, actively advocating multidisciplinary cooperation during early orthodontic treatment and understanding face management in a serious way.

[Early orthodontic treatment of malocclusion in the mixed dentition]

Children in the mixed dentition grow rapidly, and various types of malocclusion often appear in this period. At the same time, there are many environmental factors affecting the development of the occlusion at this stage. Functional abnormalities related to lip, tongue, articulation and breathing, and impacted teeth should be actively intervened and blocked to avoid the continued development of the deformity. Appropriate orthopedic devices should be used in patients with skeletal malocclusion, if necessary, for growth modification and the influence of congenital factors and the prognosis of treatment should be fully evaluated. Over-intervention of the temporary malocclusions in the mixed dentition should be avoided. In conclusion, early orthodontic treatment in the mixed dentition requires a comprehensive assessment of the treatment need, risks, timing, cost and the ultimate benefit of the patient. The timing of orthodontic treatment is not the sooner the better. The indications must be strictly controlled, and the necessity and limitations must be carefully considered.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

[Correlation between nUGT1A1 gene polymorphisms and adverse events of irinotecan plus S-1 for patients with recurrent or metastatic esophageal squamous cell carcinoma: a prospective, open-label, randomized controlled trial (ESWN 01)]

Objective: To investigate the correlation between UGT1A1 polymorphisms and the irinotecan plus S-1 regimen-induced toxicities in Chinese advanced esophageal squamous cell carcinoma (ESCC) patients. Methods: A total of 46 recurrent or metastatic ESCC patients selected from ESWN 01 trial were randomly assigned to irinotecan plus S-1 group [intravenous infusion of irinotecan (160 mg/m(2)) on day 1 and oral S-1 (80-120 mg) on days 1-10, repeated every 14 days]. Peripheral venous blood at baseline was collected and genomic DNA was extracted. The genetic polymorphisms of UGT1A1*6 and UGT1A1*28 were analyzed by polymerase chain reaction (PCR) amplification. Irinotecan plus S-1 regimen-induced toxicities of patients with different UGT1A1 polymorphisms were observed. The correlation between UGT1A1 polymorphisms and the adverse effects was analyzed. Results: Among the 46 patients, the numbers of UGT1A1*6 wild type genotype (GG), mutant heterozygote (GA) and mutant homozygote (AA) were 30, 15 and 1, while those with UGT1A1*28 wild type genotype (TA6/6), mutant heterozygote (TA6/7) and mutant homozygote (TA7/7) were 36, 8 and 2, respectively. Only one patient with UGT1A1*6 AA genotype occurred grade 3 diarrhea, while one of the 2 patients with UGT1A1*28 TA7/7 genotype occurred grade 4 diarrhea. No neutropenia was observed in the patient with UGT1A1*6 AA genotype, however, both of the two patients with UGT1A1*28 TA7/7 genotype occurred grade 3-4 neutropenia. Patients with UGT1A1*28 genetic polymorphism (TA 6/7 or TA7/7) had a higher response rate compared with wild-type TA6/6 carriers. (55.6% versus 26.5%). Conclusions: The homozygous genotype of UGT1A1*6 AA and UGT1A1*28 TA7/7 are rare (<5%) in Chinese ESCC population. Not all homozygous AA and TA7/7 carriers occur severe dose limited toxicities (DLT) when treated with irinotecan (160 mg/m(2)) plus S-1 regimen for 2 weeks. However, it's still necessary torigorously observe the occurrence of severe diarrhea and neutropenia in patients with UGT1A1*6 AA and UGT1A1*28 TA7/7 and adjust the dose timely.

[Periodontal support and escort for healthy orthodontic treatment]

Health and support of periodontal tissue is the basis for achieving excellent, safe and efficient orthodontic treatment outcome, which also guarantees the esthetics, stability and function of treatment objectives. The support of healthy periodontal tissue contributes to the stability of teeth. Orthodontic treatment also requires adaptive periodontal reconstruction during tooth movement. Well-aligned teeth and balanced occlusion play an important role in maintaining and improving periodontal homeostasis. Healthy orthodontic treatment can improve the health of periodontal structure and functions, which has to rely on the existence and reconstruction of healthy periodontal tissue. Therefore, orthodontics and periodontal health have dialectically close association and mutual maintenance. Favorable "periodontal support and escort" is indispensable for healthy orthodontic treatment.

[Interpretation of guidelines for clear aligner orthodontic treatment (2021)]

"Guidelines for clear aligner orthodontic treatment (2021)" proposes clinical treatment recommendations in terms of practitioner requirements, clinical risks, diagnosis, treatment plan, and common clinical strategies for the orthodontic clear aligners technology. This article interprets the 2021 version of the guidelines to facilitate readers' better understanding and application in clinical practice.

Peta-electron volt gamma-ray emission from the Crab Nebula

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10^-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 10³⁶ ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25  TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160  TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 10¹⁵ electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays¹. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. ²). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane^3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

[Risk perception and management in orthodontic treatment]

With the improvement of people's living standards and oral health education, the demand for orthodontic treatment is increasing. The comprehensive goal of orthodontic treatment is not only to obtain esthetic dentition and appearance, but also to obtain oral health, general health and mental and psychological health. Therefore, how to effectively prevent the risks in orthodontic treatment is particularly important, and it is also an important content that orthodontists must master. In this paper, the prevention of related risks in orthodontic treatment was discussed.

[Clinicopathological features and prognosis of pediatric alveolar rhabdomyosarcoma]

Objective: To investigate the clinicopathological features, diagnosis, differential diagnosis, treatment and prognosis of pediatric alveolar rhabdomyosarcoma (ARMS). Methods: The clinical and pathological data of 25 pediatric ARMS from 2008 to 2018 in Children's Hospital of Fudan University were collected. This histomorphology was assessed, and FOXO1 gene rearrangement was detected with FISH. The treatment details and outcome were analyzed. Results: There were 13 males and 12 females, with ages range from 19 days to 14 years (median 6 years, mean 6.2 years). The ARMS were located in the limbs (13 cases), head and neck (4 cases), trunk (3 cases), abdominal cavity (3 cases), scrotum (1 case) and perianal region (1 case). The ARMS were classified histologically as classic group (18 cases), solid group (5 cases) and embryonic-alveolar mixed group (2 cases). The typical pathological characteristics were small dark round cells arranged in solid, glandular and papillary patterns. The tumor cells expressed ALK (D5F3) (21/25, 84.0%), muscle origin DES (23/25, 92.0%), myogenin (22/25, 88.0%), MYOD1 (19/25, 76.0%), and in some cases they also expressed neurogenic marker Syn (6/25, 24.0%). FOXO1 gene rearrangement was detected by FISH in 24/25 cases (96.0%). Conclusion: Pediatric ARMS is rare and has unique clinicopathological characteristics, and needs to be differentiated from other common small round cell malignancies in children. ALK, DES, myogenin, MYOD1 immunohistochemistry and FOXO1 gene rearrangement are valuable aid in the diagnosis of ARMS.

[Mechanism of angiotensin II (Ang II) on the proliferation of human hepatoma cell line HepG2 cells]

Objective: To study the effect and mechanism of angiotensin (Ang II) on the proliferation of human hepatocellular carcinoma HepG2 cells. Methods: The effects of different concentrations of Ang II's (10(-8)-10(-4) mol/L) on proliferated hepatocellular carcinoma HepG2 cells were detected by CCK-8 assay. The expression of angiotensin II type 1 receptor (AT1) protein and activation of ERK1/2 protein in hepatocellular carcinoma HepG2 cells after processing with Ang II were assayed by Western blot. The cells were pretreated with candesartan (AT1 receptor antagonist), sorafenib (Raf kinase inhibitor) and PD98059 (ERK1/2 inhibitor) for 1.5 h and then Ang II (10(-6) mol/L) was added. CCK-8 assay was used to determine whether it could reverse the proliferation of Ang II, and ERK phosphorylation levels were detected by Western blot. The changes in Bcl-2 and c-myc gene expression before and after Ang II processing were detected by Rt-PCR. According to different data, t-test, one-way analysis of variance or SNK method were used for statistical analysis. Results: HepG2 cells treated with different concentrations of Ang II promoted cell proliferation after 24h and 48h. After 24 h, cell vitality was strongest with Ang II concentration 10(-5) mol/L and the absorbance value was 0.990 8±0.097 8; and again after 48 h, the cell viability was strongest with Ang II concentration 10(-6) mol/L and the absorbance value was 1.302 7 ± 0.030 9. Moreover, the pro-proliferation effect of Ang II on HepG2 cells blocked candesartan, sorafenib and ERK1/2 isolated inhibitors. After treatment with 10(-6) mol/L Ang II, Western blot showed that Ang II significantly promoted AT1 receptor expression and phosphorylation of ERK1/2 protein confirmed that Ang II activated the AT1/RAF/ERK1/2 signaling pathway. In addition, Rt-PCR detection showed that the downstream of Bcl-2 and c-myc genes expressions rose significantly when the concentration of Ang II ranged from 10(-8) to 10(-6) mol/L. Conclusion: Ang II can promote the proliferation of HepG2 cells by activating AT1/Raf /ERK1/2 signaling pathway and enhance the downstream of Bcl-2 and c-myc gene expression.

[Effects of budesonide aerosol inhalation on the immunological functions of peripheral dendritic cells in patients with allergic rhinitis]

Objective: To investigate the immunologic functional changes of peripheral dendritic cells (DC) in patients with allergic rhinitis (AR) during the treatment by budesonide aerosol inhalation.Method:25 patients with moderate to severe persistent AR were concluded in current study, and they were given budesonide aerosol inhalation for 8 weeks. AR related nasal symptom scores and indices, peripheral DC counts and percentages as well as their activation before and 4 weeks, 8 weeks after treatment were determined.Result:There were significant decrease in nasal symptom scores, eosinophils, AR specific IgE antibodies after 4 and 8 weeks of treatment. The overall clinical efficiency reached 88% at the end of the treatment. Peripheral DC counts and DC/PBMC decreased in comparison with the levels of pre-treatment (P<0.05). Compared with the levels before treatment, DC activation markers CD86 and CD80 reduced to various extent, while glucocorticoid-induced leucine zipper (GILZ) positive cells gradually elevated (P<0.05). In the DC secreted IL-10 decreased against the treatment duration, while IFN-γ from DC conditioned T cells statistically increased after treatment (P<0.05). Conclusion:Budesonide suppressed DC activation and maturation, which might redirect DC-involved Th2 response, in turn alleviating the AR symptoms.

[Three-dimensional printed miniplate used for maxillary protraction]

The miniplate was designed and three-dimensional (3D) printed according to the positions of roots and tooth germs and then it was used as skeletal anchorage to protract the maxilla. The maxilla moved forward obviously after treatment. Custom designed and 3D printed miniplate could be used for maxillary protraction.

[Risk factors for central neck lymph node metastases of papillary thyroid carcinoma]

Objective: To investigate the impact factors for central neck lymph node metastases(CLNM) of papillary thyroid carcinoma(PTC). Methods: A total of 498 patients with PTC who underwent total or hemi-thyroidectomy plus central neck lymph node dissection between January 2014 and July 2016 were included. Univariate and multivariate analyses were performed to identify clinicopathological characteristics, thyroid function parameters and US findings that associated with CLNM of PTC. A nomogram was developed to predict the probability of CLNM. The receiver operating characteristic curve(ROC) was used to estimate the efficiency of the nomogram. Results: Among 498 patients, 284 patients were affected by CNLM. The sensitivity and specificity of US in predicting PTC metastasis in the central neck were 31.3% and 88.3%, respectively. Univariate and multivariate analyses showed that gender, age, number and size of suspicious malignant nodules in thyroid, and suspicious lymph node metastasis detected by ultrasonography were independently correlated with CLNM. The ROC showed that the AUC was 0.748, with sensitivity of 80.8%, and specificity of 59.8%. Conclusions: Gender, age, number and size of suspicious malignant nodules in thyroid, suspicious lymph node metastasis were predictive factors for CLNM in patients with PTC. The nomogram developed based on related factors with CLNM is more sensitive than sonographic central neck lymph node features in predicting the probability of CLNM.

Developing a New Generation of Antimicrobial and Bioactive Dental Resins

Dental caries is prevalent, and secondary caries causes restoration failures. This article reviews recent studies on developing a new generation of bioactive resins with anticaries properties. Extensive effects were made to develop new antimicrobial composites, bonding agents, and other resins containing quaternary ammonium methacrylates to suppress plaque buildup and bacterial acid production. The effects of alkyl chain length and charge density and the antimicrobial mechanisms for chlorhexidine, nano-silver, quaternary ammonium methacrylates, and protein-repellent agents were discussed. Synergistic effects of contact-killing and protein-repellent properties were shown to yield the greatest biofilm-inhibition effects. The combination of antimicrobial, protein-repellent, and calcium phosphate nanoparticle remineralization was suggested to provide maximal anticaries effects. In addition, for use orally, cytotoxicity and biocompatibility were important considerations for the new bioactive materials. Furthermore, rather than kill all bacteria, it would be more desirable to modulate the oral biofilm compositions via bioactive resins to suppress cariogenic/pathogenic species and promote benign species. For widespread clinical use of the new antimicrobial and therapeutic materials, whether they would induce bacterial drug resistance needs to be determined, which requires further study. Nonetheless, the new generation of bioactive anticaries resins with therapeutic and biofilm acid-inhibiting properties has the potential to substantially benefit oral health.

The Growth Hormone Receptor Gene is Associated with Mandibular Height in a Chinese Population

Genetic influences are important in the determination of mandibular morphology, and growth hormone receptor ( GHR) is believed to have an important influence on the growth of craniofacial bone. In this study, we used quantitative trait locus methods to evaluate the relationship between craniofacial morphology and single-nucleotide polymorphisms (SNPs) in GHR in an unselected healthy Chinese population. We systematically screened the 10 exons and nearby introns of GHR and identified 6 SNPs. Using 4 SNPs as markers, we studied the relationships between genotypes and craniofacial linear measurements. Individuals with the genotype CC of polymorphism I526L had a significantly greater mandibular ramus length (condylion-gonion/ articulare-gonion) than those with genotype AC or AA. Haplotype analysis showed that there were also significant differences between the long and short mandibular height groups in an extreme population. Our results indicate that the GHR gene polymorphism I526L is associated with mandibular height in the Chinese population.

[Protein-repellent and antibacterial properties of modified orthodontic adhesive]

OBJECTIVE

To develop a novel protein-repellent orthodontic adhesive by incorporating 2-methacryloyloxyethyl phosphorylcholine(MPC).

METHODS

MPC was incorporated into a commercially available orthodontic adhesive(Fuji ORTHO) at 0% (control), 1.5%, 3.0%, and 5.0% by mass. Enamel shear bond strength(SBS) was determined. Protein adsorption onto specimens was determined by a micro bicinchoninic acid method. A dental plaque microcosm biofilm model with human saliva as inoculum was used to investigate biofilm viability.

RESULTS

The SBS was not reduced in the group(3.0% MPC), compared to the control group. The amount of protein adsorption in the group(3.0% MPC) was (0.46±0.06) μg/cm(2) and (4.57 ± 0.42) μg/cm(2) in the control group. Lactic acid production of biofilms in the group(3.0% MPC) was (7.12±1.03) mmol/L and (12.16±1.24) mmol/L in the control group.

CONCLUSIONS

MPC based orthodontic adhesive greatly reduced the protein adsorption and bacterial adhesion, without compromising enamel shear bond strength.

[Accuracy and reliability of three-dimensional craniofacial cone-beam CT superimposition method based on voxel registration]

OBJECTIVE

To set up a three-dimensional(3D)craniofacial cone-beam CT(CBCT)superimposition method based on voxel registration, and evaluate the accuracy and reliability of different reference superimposition areas.

METHODS

CBCT scans were taken on a dry skull for three times with a time-interval of two weeks, and CBCT scans were taken on ten adult volunteers twice with a time-interval of one month. The 3D superimposition based on voxel registration was set up by means of Analyze 12.0. The bilateral-zygomatic bone and anterior cranial base were selected as different reference areas for voxel overlapping. The 3D overlapping images were output into Geomagic Qualify 2013, and the surface distances on different craniofacial regions were measured. Three operators repeated three times of these superimposition and measurement. SPSS 19.0 were used to analyze the accuracy and reliability.

RESULTS

When bilateral-zygomatic bone used as superimposition reference, the mean surface distance range of dry skull were from 0.035 to 0.064 mm, and volunteers from 0.099 to 0.182 mm. When the anterior cranial base used as superimposition reference, the mean surface distance range of dry skull were from 0.038 to 0.071 mm, and volunteers from 0.127 to 0.218 mm. All these mean values were less than the CBCT voxel size 0.25 mm(P<0.05), and got sub-pixel precision. No significant difference was found between the different operators at different times(P>0.05).

CONCLUSIONS

This study showed the high accuracy and reliability of 3D CBCT superimposition based on voxel registration, either the anterior cranial base or the bilateral-zygomatic bone as reference. This method could be used for evaluating 3D craniofacial treatment effects.

[The reliability of electrochemical enzyme-linked immunosorbent assay for detection of dentin sialophosphoprotein in gingival crevicular fluid]

OBJECTIVE

To investigate the reliability of electrochemical enzyme-linked immunosorbent assay(ELISA)for the detection of dentin sialophosphoprotein(DSPP)in gingival crevicular fluid(GCF)of orthodontic patients.

METHODS

GCF were collected from the orthodontic patients, and then the amount of DSPP in GCF were detected by electrochemical ELISA and spectroscopic ELISA respectively. The difference between the results of two methods were analyzed.

RESULTS

In electrochemical ELISA, the second order derivative linear sweep voltammetric peak current was linear with DSPP concentration in the range from 0.25-800.00 ng/L. It was found that the detection limit of the electrochemical method(0.25 ng/L)was much lower than that of the spectroscopic method. The paired-samples rank sum test showed no significant difference between the DSPP concentrations in human GCF samples measured by spectroscopic ELISA procedure and those measured by electrochemical ELISA procedure(P=0.063).

CONCLUSIONS

Electrochemical ELISA is a viable way of detecting DSPP in GCF with higher sensitivity than spectroscopic ELISA.

[Application of three-dimensional digital technology in the diagnosis and treatment planning in orthodontics]

Three-dimensional(3D)digital technology has been widely used in the field of orthodontics in clinical examination, diagnosis, treatment and curative effect evaluation. 3D digital technology greatly improves the accuracy of diagnosis and treatment, and provides effective means for personalized orthodontic treatment. This review focuses on the application of 3D digital technology in the field of orthodontics.

Effect of odanacatib on root resorption and alveolar bone metabolism during orthodontic tooth movement

The aim of this study was to investigate the effect of local administration of odanacatib (ODN) on orthodontic root resorption and the status of alveolar bone metabolism in rat molars. All specimens were scanned using microcomputed tomography and then the raw images were reconstructed. The total volume of the root resorption craters of the 60 g-NS (normal saline) group was higher than in the 60 g-ODN group and the control group. In the 60 g-NS group, the bone volume fraction values of alveolar bone were significantly decreased compared with the other 2 groups. There were no significant differences in the bone volume fraction values of the tibiae among the 3 groups. The results of tartrate-resistant acid phosphatase-positive (TRAP+) numbers showed that there was no difference between the 60 g-NS group and the 60 g-ODN group. The expression of cathepsin K was decreased significantly in the 60 g-ODN group. These results indicate that ODN reduces orthodontics-induced external root resorption and increases alveolar bone metabolism. This may be because ODN inhibits the activity of odontoclasts, but maintains the quantity of odontoclasts and enhances bone formation. ODN promotes local alveolar bone metabolism, but does not affect systemic bone metabolism.

Effect of A disintegrin and metalloproteinase 10 gene silencing on the proliferation, invasion and migration of the human tongue squamous cell carcinoma cell line TCA8113

The present study aimed to investigate the effect of A disintegrin and metalloproteinase 10 (ADAM10) gene silencing on the proliferation, migration and invasion of the human tongue squamous cell carcinoma cell line TCA8113. RNA interference was used to knock down the expression of ADAM10 in the TCA8113 cell line and the proliferation, migration and invasive ability of the treated cells were observed in vitro. The expression levels of epidermal growth factor receptor (EGFR) and E-cadherin in the treated cells were determined by western blot analysis. The proliferation, migration and invasion abilities of cells in the ADAM10 siRNA-treated group were significantly lower than those in the control groups (P<0.05). In addition, compared with the control groups, the expression levels of EGFR and E-cadherin in the ADAM10 siRNA-treated cells were significantly decreased (P<0.05) and increased (P<0.05), respectively. These results suggested that ADAM10 is important in regulating the proliferation, invasion and migration of the human tongue squamous cell carcinoma cell line TCA8113 and that the mechanism may, at least in part, be associated with the upregulation of EGFR and the downregulation of E-cadherin.

Direct bioconversion of raw corn stalk to hydrogen by a new strain Clostridium sp. FS3

A new strain FS3 which could achieve an efficient bioconversion of raw corn stalk to hydrogen had been isolated from anaerobic acclimated sludge, and identified as Clostridium butyricum on the basis of a series of physiological and biochemical experiments and 16S rDNA gene sequence. The strain could utilize various carbon sources to produce hydrogen. On the basis of single-factor experiments, the response surface methodology (RSM) was performed to optimize the media for hydrogen production. The maximum hydrogen yield of 92.9ml/g was observed under the optimal conditions: 20g/l raw corn stalk, 1.76g/l NH4HCO3, 0.91g/l KH2PO4 and 10.4ml/l nutrient solution. This finding opens a new avenue for direct conversion of raw cellulosic biomass to bio-hydrogen.

[Induction of apoptosis of leukemic tumor cells in mouse model with G-quadruplex ligand Tel03]

This study was aimed to investigate the anti-leukemia activity of Tel03 in vivo. The K562 xenografted leukemia model was established and mice were divided randomly into three groups. Mice of different group were treated with PBS (control), 5 mg/kg Tel03 or 15 mg/kg Tel03 (ip, twice a week) respectively. Tumor volume, body weight and other behavior were observed regularly. Cell apoptosis was detected with TUNEL assay and the expression levels of Bcl-2 and Bax were detected by Western blot. The results indicated that Tel03 exerted anti-leukemia activity in mouse model. Tel03 significantly reduced tumor volume in Tel03-treated group compared with control. In addition, 5 mg/kg Tel03 induced cell apoptosis without exerting apparent toxicity in mice. After Tel03 treatment, the expression of Bcl-2 was inhibited, however, the expression of Bax was up-regulated. It is concluded that G-quadruplex ligand Tel03 can induce cell apoptosis in leukemia mouse model, and this agent may be a potential anticancer drug.

Evaluation of the air bronchogram sign on CT in solitary pulmonary lesions

PURPOSE

Our goal was to evaluate the presence and the significance of the air bronchogram sign in solitary pulmonary lesions (SPL) on CT.

METHOD

One hundred thirty-two patients with SPL who underwent chest CT scans and had histological diagnosis were studied retrospectively. We reviewed all chest CT scans to assess for the presence of the air bronchogram sign in the SPL and recorded the distribution of this sign in malignant and benign lesions. The morphology of the aerated bronchi in the lesion and its significance in differential diagnosis were also evaluated.

RESULTS

Of 17 cases of benign lesions, only 1 (5.9%) had an air bronchogram; of 115 lung cancers, 33 (28.7%) had this sign (p < 0.05). The encased bronchi exhibited four morphologic patterns: normal, tortuous, ectatic, and cut-off. The morphology of the bronchus in the benign lesion was normal. However, bronchi in malignant lesions displayed all four types of morphology. The air bronchogram sign was seen in all histologic types of lung cancer (squamous cell 10, adenocarcinoma 9, bronchioloalveolar cell 12, small cell 1, non-small cell 1). Lesions of different sizes were noted to have air bronchograms, including those < 2 cm in diameter.

CONCLUSION

The CT air bronchogram sign in SPL is significantly more common in malignant than in benign lesions. The sign is seen in all lung cancer cell types and demonstrates varied bronchial morphology.

[One stage reconstruction of bladder exstrophy and epispadias with abdominal wall skin flap and rectus abdominis muscle flap: report of 5 cases]

5 cases of complete bladder exstrophy were treated by one stage reconstruction with abdominal wall skin flap and rectus abdominis muscle flap. Closure of the abdominal wall and bladder defect were achieved satisfactorily in all the patients. 4 patients have been followed up for 1.5-10.5 years. 3 patients whose bladder neck had been augmented by rectus abdominis muscle flap were continent but 1 patient whose bladder neck had not been, had giggle incontinence. The renal functions were all normal in these patients.

Homotransplantation of testis. A report of 11 cases

Testis homotransplantation has been carried out in 11 patients since 1986. Of them, 8 suffered from congenital testicular dysplasia and the other 3 from orchiatrophy as a result of orchitis. Preoperatively, manifestations were a small penis, small testes, sexual dysfunction, indistinct secondary sex characteristics and low serum testosterone (1.7-7.35 mmol/L). Three cases had cadaver transplants and 8 had living relatives' transplants. The patients were followed up for 7 months to 4 years. The secondary sex characteristics and sexual function were improved remarkably after transplantation. Serum testosterone increased up to 12.8-18.2 mmol/L. All of 5 married patients resumed sexual intercourse satisfactorily. Three others got married after transplantation and have enjoyed normal sexual functions. Spermatozoa have been found in the semen in 3 of the cases.

[MRI diagnosis of mediastinal tumors: a report of 20 cases]

With the use of MRI, 20 pathologically proved cases of mediastinal tumor were analysed, of which 13 cases were also studied with CT. Compared with CT, the three-dimensional morphological study of the lesions by MRI provided better evaluation of their location and of their characteristics. The abnormal signals on T1WI, PDWI and T2WI images, particularly of lipoma, fluid-contained cyst, lymphoma and cystic teratoma, were highly accurate in diagnosing mediastinal tumors; in addition, MRI was ideal for demonstrating the tumor capsule in neurogenic tumor or fibrous septa within the lipoma. Specific MRI findings facilitate the diagnosis of an aneurysm. Finally, the limitations of MRI were also discussed.

[X-ray diagnosis of non-lymphomatous lymphoid disorders of the chest]

The non-lymphomatous lymphoid disorders of the chest are rare conditions characterized by infiltration of the pulmonary interstitium with lymphocytes and plasma cells. This article reported 6 pathologically proved cases, including Castleman's disease (3), pseudolymphoma (1), angioimmunoblastic lymphadenopathy (1), and lymphomatoid granulomatosis (1). The X-ray findings of these lesions were rather characteristic. In our series, the chest film showed large patchy areas of consolidation sometimes with the presence of air bronchogram in pseudolymphoma and lymphomatoid granulomatosis, simulating bronchiolo-alveolar carcinoma or pulmonary lymphoma roentgenologically. However, the former developed very slowly with little clinical symptoms. Most of the Castleman's disease in this series were found in young adults showing conspicuous, sharply marginated mediastinal node enlargement. Recognition of the aforementioned signs would bring about greater diagnostic accuracy.