Orthodontic-surgical treatment for severe skeletal class Ⅱ malocclusion with vertical maxillary excess and four premolars extraction: A case report

BACKGROUND Patient satisfaction with facial appearance at the end of orthodontic camouflage treatment is very important, especially for skeletal malocclusion. This case report highlights the importance of the treatment plan for a patient initially treated with four-premolar-extraction camouflage, despite indications for orthognathic surgery.CASE SUMMARY A 23-year-old male sought treatment complaining about his unsatisfactory facial appearance. His maxillary first premolars and mandibular second premolars had been extracted, and a fixed appliance had been used to retract his anterior teeth for two years without improvement. He had a convex profile, a gummy smile, lip incompetence, inadequate maxillary incisor inclination, and almost a class I molar relationship. Cephalometric analysis showed severe skeletal class Ⅱ malocclusion(A point-nasion-B point = 11.5°) with a retrognathic mandible(sella-nasion-B point = 75.9°), a protruded maxilla(sella-nasion-A point = 87.4°), and vertical maxillary excess(upper incisor to palatal plane = 33.2 mm). The excessive lingual inclination of the maxillary incisors(upper incisor to nasion-A point line =-5.5°)was due to previous treatment attempts to compensate for the skeletal class Ⅱ malocclusion. The patient was successfully retreated with decompensating orthodontic treatment combined with orthognathic surgery. The maxillary incisors were repositioned and proclined in the alveolar bone, the overjet was increased, and a space was created for orthognathic surgery, including maxillary impaction, anterior maxillary back-setting, and bilateral sagittal split ramus osteotomy to correct his skeletal anteroposterior discrepancy. Gingival display was reduced, and lip competence was restored. In addition, the results remained stable after 2 years. The patient was satisfied with his new profile as well as with the functional malocclusion at the end of treatment.CONCLUSION This case report provides orthodontists a good example of how to treat an adult with severe skeletal class Ⅱ malocclusion with vertical maxillary excess after an unsatisfactory orthodontic camouflage treatment. Orthodontic and orthognathic treatment can significantly correct a patient’s facial appearance.

人工智能在眼表疾病中的应用现况

近年来,随着计算机学科的进步与学科交叉融合的推进,人工智能(AI)在医学领域呈现出迅猛发展的态势,在眼科学也取得了许多突破性进展。既往AI在眼科学的应用研究大多集中在糖尿病视网膜病变、年龄相关性黄斑变性等眼底疾病。近年来,随着AI学习算法的改进以及大数据的开发利用,AI在眼科学的应用范围得以进一步拓展,越来越多的研究开始将AI应用于眼表疾病。本文综述了AI在圆锥角膜、翼状胬肉及角膜炎等眼表疾病中的相关研究和应用,探讨当前AI在眼科学临床应用中面临的挑战与机遇,并对其未来发展前景进行展望,旨在为眼科AI的发展提供新思路。

Sensing properties and mechanisms of LaF_(3)-Co_(3)O_(4) nanorods for low-concentration methanol detection

Methanol is one of the characteristic gases that distinguish between healthy individuals and lung cancer(LC)lesions in exhaled human breath.Its concentration in exhaled breath is generally below one part per million(1×10^(-6)).The second-phase composite is widely regarded as one of the methods to improve the gas-sensing perfor-mance of metal oxide semiconductor(MOS)materials.In this study,LaF_(3)-Co_(3)O_(4) was synthesized by a simple hydrothermal method to enhance its low-concentration methanol gas-sensing performance.5 at%LaF_(3)-Co_(3)O_(4) nanorods exhibited excellent methanol detection performance,including a wider linear detection concentration range(0.2×10^(-6)~5×10^(-6)),a response value exceeding 4.0 for 1×10^(-6)methanol at 275°C and 75%relative humidity(RH),long-term stability(maximum deviation within 15%over 2 weeks),and excellent selectivity.The mechanism of performance enhancement was studied using various techniques,and density functional theory.The special spinel structure of Co_(3)O_(4),the high ionic migration of F-in LaF_(3),the larger specific surface area of 5 at%LaF_(3)-Co_(3)O_(4) nanorods,and the generated crystal defects all explain the excellentmethanol gas-sensing property.This work provides a novel route to prepare MOS composite materials for low-concentration methanol gas detection.

Epididymis cell atlas in a patient with a sex development disorder and a novel NR5A1 gene mutation

This study aims to characterize the cell atlas of the epididymis derived from a 46,XY disorders of sex development(DSD)patient with a novel heterozygous mutation of the nuclear receptor subfamily 5 group A member 1(NR5A1)gene.Next-generation sequencing found a heterozygous c.124C>G mutation in NR5A1 that resulted in a p.Q42E missense mutation in the conserved DNA-binding domain of NR5A1.The patient demonstrated feminization of external genitalia and Tanner stage 1 breast development.The surgical procedure revealed a morphologically normal epididymis and vas deferens but a dysplastic testis.Microfluidic-based single-cell RNA sequencing(scRNA-seq)analysis found that the fibroblast cells were significantly increased(approximately 46.5%),whereas the number of main epididymal epithelial cells(approximately 9.2%),such as principal cells and basal cells,was dramatically decreased.Bioinformatics analysis of cell–cell communications and gene regulatory networks at the single-cell level inferred that epididymal epithelial cell loss and fibroblast occupation are associated with the epithelial-to-mesenchymal transition(EMT)process.The present study provides a cell atlas of the epididymis of a patient with 46,XY DSD and serves as an important resource for understanding the pathophysiology of DSD.

Two Monte Carlo-based simulators for imaging-system modeling and projection simulation of flat-panel X-ray source

The advantages of a flat-panel X-ray source(FPXS)make it a promising candidate for imaging applications.Accurate imaging-system modeling and projection simulation are critical for analyzing imaging performance and resolving overlapping projection issues in FPXS.The conventional analytical ray-tracing approach is limited by the number of patterns and is not applicable to FPXS-projection calculations.However,the computation time of Monte Carlo(MC)simulation is independent of the size of the patterned arrays in FPXS.This study proposes two high-efficiency MC projection simulators for FPXS:a graphics processing unit(GPU)-based phase-space sampling MC(gPSMC)simulator and GPU-based fluence sampling MC(gFSMC)simulator.The two simulators comprise three components:imaging-system modeling,photon initialization,and physical-interaction simulations in the phantom.Imaging-system modeling was performed by modeling the FPXS,imaging geometry,and detector.The gPSMC simulator samples the initial photons from the phase space,whereas the gFSMC simulator performs photon initialization from the calculated energy spectrum and fluence map.The entire process of photon interaction with the geometry and arrival at the detector was simulated in parallel using multiple GPU kernels,and projections based on the two simulators were calculated.The accuracies of the two simulators were evaluated by comparing them with the conventional analytical ray-tracing approach and acquired projections,and the efficiencies were evaluated by comparing the computation time.The results of simulated and realistic experiments illustrate the accuracy and efficiency of the proposed gPSMC and gFSMC simulators in the projection calculation of various phantoms.