AIM: To detect the distribution and expression of vascular endothelial growth factor(VEGF)in radiation retinopathy(RR)through fluorescence targeted imaging.METHODS:Covalent binding of fluorescein FITC with VEGF antibody ranibizumab to prepare targeted fluorescent imaging probe ranibizumab-FITC. SD rats were randomly divided into three groups based on the principle of weight balance: a normal control group(Con group), a low-dose radiation group(10 Gy group), and a high-dose radiation group(30 Gy group). Medical linear accelerators and lead blocks were used to locally irradiate the rat eyeballs for modeling. Western blot and qRT-PCR were used to detect the expression levels of VEGF-A in each group and to screen for appropriate modeling dose. The inverted fluorescence microscope and the confocal microscope were used to observe the distribution of VEGF and imaging probes in the retinas of control and RR model group rats, and to verify the effectiveness of targeted probes.RESULTS:The expression level of VEGF-A in the retina of rats in the high-dose radiation group(30 Gy group)was higher than that in the normal control group(Con group). In early RR, VEGF expression was observed to be associated with microaneurysms and abnormal microvessels in the retina. VEGF accumulation was observed at the site of capillary wall damage. When retinal capillary endothelial damage occurred, targeted probes gathered on the outer surface of the vessel wall.CONCLUSION:The expression level of VEGF in the retina of RR model rats is elevated, and fluorescent targeted molecular imaging probes can detect the spatial distribution of VEGF at the microvascular lesions in the retina of RR rats.

BACKGROUND:Socket-shield technique can effectively maintain labial soft and hard tissues,but the incidence of postoperative complications such as exposure and displacement of root shield is relatively high.It is speculated that the root shield may be exposed and displaced due to excessive load after long-term function of dental implants. OBJECTIVE:Through three-dimensional finite element analysis,we aim to study the influence of varying root shield thicknesses on the stress distribution,equivalent stress peaks,and displacement in the root shield,periodontal ligaments,implant,and surrounding alveolar bone under normal occlusal loading.We also attempt to analyze the correlation between the thickness of the root shield and occurrence of mechanical events such as root shield exposure,displacement,and fracture. METHODS:Cone-beam CT data of a patient who met the indication standard of socket-shield technique for maxillary central incisor were retrieved from database.Reverse engineering techniques were used to build models of the maxillary bone and root shield,while forward engineering was used to create models for the implant components based on their parameters.Models depicting various root shield thicknesses(0.5,1.0,1.5,and 2.0 mm)were created using Solidworks 2022 software.ANSYS Workbench 2021 software was then used to simulate and analyze the effects of varying root shield thicknesses on stress distribution,equivalent stress peaks,and displacement of the root shields,periodontal ligaments,implants,and surrounding alveolar bone under normal occlusion. RESULTS AND CONCLUSION:(1)In all root shield models,the stress was concentrated on the palatal cervical side,both sides of the edges and the lower edge of the labial side.As the thickness of the root shield increased,the equivalent stress peak and displacement showed a decreasing trend.The 0.5 mm thickness model produced a stress concentration of 176.20 MPa,which exceeded the yield strength(150 MPa)of tooth tissue.(2)The periodontal ligament stress in each group was concentrated in the neck margin and upper region.With the increase of root shield thickness,the equivalent stress peak and displacement of periodontal ligament showed a decreasing trend.(3)Implant stress in all models was concentrated in the neck of the implant and the joint of the implant-repair abutment,and the labial side was more concentrated than the palatal side.With the increase of root shield thickness,the equivalent stress peak of the implant in the model showed an increasing trend.(4)In each group of models,stress of cortical bone concentrated around the neck of the implant and the periphery of the root shield,and the labial side was more concentrated than the palatal side.With the increase of the thickness of the root shield,the equivalent stress peak around the root shield decreased;the peak value of the equivalent stress of the bone around the neck of the implant showed an increasing trend.In the model,the stress of cancellous bone was mainly concentrated around the neck of the lip of the implant,the top of the thread,the root tip and the lower margin of the root shield,and the labial side was more concentrated than the palatal side.With the increase of the thickness of the root shield,the peak value of the equivalent stress of the bone around the root shield in the model showed a decreasing trend.The minimum principal stress of cortical bone in each group of models was concentrated around the neck of the implant,exhibiting a fan-shaped distribution.As the thickness of the root shield increased,the minimum principal stress of cortical bone showed an increasing trend.(5)These results indicate that different thicknesses of the root shield have different biomechanical effects.The root shield with a thickness of 0.5 mm is easy to fracture.For patients with sufficient bone width,the root shield with a thickness of 2.0 mm is an option to reduce the risk of complications such as root shield exposure,fracture,and displacement.Meanwhile,it should be taken into account to protect the periodontal ligament in the preparation process,and rounding treatments ought to be carried out on both sides and the lower edge of the root shield.

Objective To explore the identification method,pathogenesis,clinical characteristics and individualized pharmacotherapy of asymptomatic hyperuricemia after renal transplantation.Methods The pharmacist was on duty at the organ transplant outpatient clinic.During this time,they analyzed and sorted out the medications,identified and differentiated a case of asymptomatic hyperuricemia related to spironolactone in a patient who had undergone a renal transplant,and provided comprehensive care throughout the entire process.Results The asymptomatic hyperuricemia in this patient might be associated with spironolactone,and the adverse reactions of the patient were alleviated by pharmacists through optimizing clinical treatment.Up to now,no hyperuricemia occurred.Conclusions Pharmacists are required to collaborate closely with clinicians to establish medication profiles for patients under long-term follow-up and to closely monitor and evaluate drug-related adverse reactions.Additionally,they should assess the renal function and immune status of transplant recipients promptly and formulate individualized treatment plans in order to enhance the long-term survival of both the transplanted kidneys and the recipients.

High altitude heart disease(HAHD)is a chronic mountain sickness in which the body is exposed to high altitude(＞2 500 m)hypobaric hypoxia environment for a long time.HAHD has high morbidity and poor prognosis,and pulmonary hypertension is the main causative mechanism for its develop-ment.The phosphodiesterase-5 inhibitor sildenafil has become a hot drug for the treatment of pulmonary hypertension.This paper reviews the progress of HAHD and discusses the mechanism of action and effectiveness of sildenafil in the treatment of HAHD,with a view to providing a basis for the treatment of HAHD with sildenafil.

High altitude heart disease(HAHD)is a chronic mountain sickness in which the body is exposed to high altitude(＞2 500 m)hypobaric hypoxia environment for a long time.HAHD has high morbidity and poor prognosis,and pulmonary hypertension is the main causative mechanism for its develop-ment.The phosphodiesterase-5 inhibitor sildenafil has become a hot drug for the treatment of pulmonary hypertension.This paper reviews the progress of HAHD and discusses the mechanism of action and effectiveness of sildenafil in the treatment of HAHD,with a view to providing a basis for the treatment of HAHD with sildenafil.

Objective:To compare bowel function 12 months after surgery between side-to-end anastomosis (SEA) and end-to-end anastomosis (EEA) groups of patients who had undergone rectal cancer resection.Methods:This single-center, prospective, open-label, phase III randomized controlled trial was approved by the Ethics Committee of Peking University People's Hospital (2018PHB040-01) and registered at ClinicalTrials. org (NCT03669237). Inclusion criteria were as follows: (1) histologically confirmed rectal adenocarcinoma; (2) tumor located 0 to 12 cm from the anal verge; (3) age≥18 years; and (4) planned R0 resection with primary reconstruction. Exclusion criteria included: (1) emergency surgery; (2) cognitive impairment; (3) non-primary anastomosis; (4) history of left-sided colonic or anorectal surgery; and (5) preexisting chronic defecation dysfunction. Eligible rectal cancer patients scheduled for elective sphincter-preserving surgery at Peking University People's Hospital were prospectively enrolled between October 2018 and March 2021 and randomly assigned to either the EEA group or the SEA group via computer-generated numbers prior to entering the operating room. All patients underwent standard radical tumor resection. Bowel function was evaluated by the low anterior resection syndrome (LARS) questionnaire. It consists of five single-choice questions and yields a total score ranging from 0 to 42. Defecation function is categorized into three levels: no LARS (0-20 points), minor LARS (21-29 points), and major LARS (30-42 points). The primary endpoint was the LARS score 12 months after surgery. Secondary endpoints included LARS scores from 1 to 11 months and during long-term follow-up(>12 months). The final follow-up was completed in July 2022. All randomized patients were included in the intention-to-treat set (ITTS). The full analysis set (FAS) was defined as ITTS patients with valid outcome data. All primary statistical analyses were performed in the FAS, and results were further compared in the per-protocol set (PPS) based on the actual treatment received.Results:A total of 323 patients underwent eligibility assessment, of whom 71 did not meet the inclusion criteria and 52 declined to participate. Ultimately, 200 patients were randomized. Median age was 64 years and 85 were women. The SEA and EEA groups comprised 102 and 98 patients, respectively. A total of 181 patients (90.5%) were included in the FAS, and 170 (85.0%) were included in the PPS. Among these, the 12-month LARS score was evaluated in 178 patients (98.3%) in the FAS and in 167 (98.2%) in the PPS. Median LARS score at 1–12 months were significantly lower in the SEA group in both the FAS dataset [12 months:8 (interquartile range [IQR], 0–22) vs. 14 (IQR, 8–29); Z=2.687, P=0.007] and the PPS dataset [12 months: 8 (IQR, 0–22) vs. 14 (IQR, 6–29); Z=2.543, P=0.011]. During long-term follow-up, the median LARS score was also significantly lower in the SEA group in the FAS dataset [2 (IQR, 0–4) vs. 11 (IQR, 2–23); Z=2.968, P=0.003] and the PPS dataset [2 (IQR, 0–14) vs. 11 (2, 27); Z=2.687, P=0.007]. Conclusion:Compared with the EEA group, bowel function was superior in the SEA group 1 year after surgery and during long-term follow-up.

Porcine deltacoronavirus(PDCoV)is the main pathogen of porcine deltacoronavirus dis-ease.After infection,pigsmanifest a series of main symptoms,such as persistent vomiting,watery diarrhea and severe dehydration.Pigs at almost all growth stages are likely to be infected with the virus,especially suckling piglets are much sensitive to the virus.Once PDCoV infects the host,it u-sually causes significant immunosuppression.In recent years,studies on the immunosuppressive mechanism of PDCoV have gradually attracted widespread attention.The results showed that mul-tiple proteins of PDCoV were involved in the regulation of host innate immunity,revealing the mechanism of these proteins in regulating host innate immunity.In this paper,the interaction mechanism between PDCoV protein and host innate immunity were rsummarized,which will pro-vide a theoretical basis for further understanding the pathogenesis of PDCoV and effective preven-tion and control of porcine delta coronavirus disease.

Objective:To evaluate the applicability of a new anti-G capability assessment trainer (AG-CAT) in high-performance (HP) anti-G maneuver training and positive pressure breathing for high-G (PHP) training for pilots.Methods:A total of 142 fighter pilots who were subjected to anti-G maneuver training at Dujiangyan Special Crew Sanatorium of PLA Air Force between January and November 2023 were enrolled. According to the Guidelines for Aviation Physiological Training, 123 pilots underwent both HP anti-G maneuver training and PHP positive pressure breathing training, 15 received only HP training, and 4 received only PHP training. Based on the training devices used, these pilots were divided into AG-CAT group and an anti-G and anti-hypoxia capability detection instrument (GHyCDI) group. The 2 groups were compared regarding the pedal force of lower limbs, blood pressure, and improvement of +G z tolerance during training. Results:Of the 138 pilots undergoing HP training, 88 used AG-CAT and 50 used GHyCDI. One hundred and twenty-seven pilots participated in PHP training, with 73 in the AG-CAT group and 54 in the GHyCDI group. During HP training, the pedal force of left lower limbs in the AG-CAT group was greater than that of the right limbs and of the GHyCDI group ( t=4.38, 2.64, P<0.001, =0.009). In PHP training, the AG-CAT group exhibited greater pedal force in left limbs than in right ones, while the GHyCDI group showed an opposite trend ( t=2.25, 3.37, P=0.029, 0.002). Systolic and diastolic blood pressures during HP training (with or without anti-G suits) were higher in the AG-CAT group than in the GHyCDI group ( t=3.50, 3.72, 2.55, 4.21, P=0.001,<0.001,=0.012,<0.001). Similarly, during PHP training, both systolic and diastolic pressures were higher in the AG-CAT group ( t=2.03, 3.81, P=0.045,<0.001). The AG-CAT group demonstrated superior improvements in +G z tolerance during HP training (without/with anti-G suits: Z=2.14, 3.21, P=0.049, 0.001) and PHP training ( Z=2.56, P=0.010) compared with the GHyCDI group. Conclusions:AG-CAT shows excellent applicability in aviation physiological training of pilots. Its ergonomic design, practical functionalities and enhanced compatibility with personnel protective equipment can better meet training requirements compared to conventional devices.

Objective:To validate the accuracy of three-dimensional anatomical models reconstructed from cone beam CT (CBCT) using micro-CT as the gold standard, and to evaluate the feasibility of performing anatomical analyses on such models.Methods:A total of 13 isolated deciduous teeth with intact roots were collected, including 5 anterior teeth and 8 molars, with a total of 34 root canals. The teeth were extracted from children aged 3-9 years who visited Peking University Hospital of Stomatology from January 2019 to April 2022 due to trauma or periapical disease, and were then scanned by micro-CT (with a voxel size of 0.018 mm) and CBCT (with a voxel size of 0.125 mm), respectively. Using a threshold-based semi-automated region segmentation method, anatomical models of these isolated teeth were reconstructed from the two CTs. Subsequently, the two CT reconstructed models were registered based on the iterative closest point algorithm, followed by deviation analysis. The key anatomical parameters were measured on the micro-CT and CBCT models, respectively, and the differences were calculated.Results:The CBCT reconstruction models were relatively accurate in the hard tissue morphology, and 97.1% (33/34) of the root canals were identified accurately. When it comes to the deviation analysis, the average distance between the matched points on the CBCT reconstruction models and the micro-CT models was (0.01±0.03) mm for the hard tissue, and (0.00±0.03) mm for the pulp chambers and canals, which did not affect clinical observation. The hard tissue and root canal length of CBCT models were both smaller than those of micro-CT models ( P<0.05), with a 95% limits of agreement of (-0.70, 0.14) mm for the hard tissue, and a 95% limits of agreement of (-1.93, 1.00) mm for the pulp chambers and canals. The impact of these differences on clinical operations was all within the acceptable range. Conclusions:Using micro-CT as a validate standard, CBCT with a voxel size of 0.125 mm was proved to be an effective tool for the reconstruction of deciduous teeth. Therefore, the reconstructed models were appropriate for studying deciduous teeth anatomy.

Porcine deltacoronavirus(PDCoV)is the main pathogen of porcine deltacoronavirus dis-ease.After infection,pigsmanifest a series of main symptoms,such as persistent vomiting,watery diarrhea and severe dehydration.Pigs at almost all growth stages are likely to be infected with the virus,especially suckling piglets are much sensitive to the virus.Once PDCoV infects the host,it u-sually causes significant immunosuppression.In recent years,studies on the immunosuppressive mechanism of PDCoV have gradually attracted widespread attention.The results showed that mul-tiple proteins of PDCoV were involved in the regulation of host innate immunity,revealing the mechanism of these proteins in regulating host innate immunity.In this paper,the interaction mechanism between PDCoV protein and host innate immunity were rsummarized,which will pro-vide a theoretical basis for further understanding the pathogenesis of PDCoV and effective preven-tion and control of porcine delta coronavirus disease.