1.Finite element analysis of various root shield thicknesses in maxillary central incisor socket-shield technique
Guangneng CHEN ; Siyang LUO ; Mei WANG ; Bin YE ; Jiawen CHEN ; Yin LIU ; Yuwen ZUO ; Xianyu HE ; Jiajin SHEN ; Minxian MA
Chinese Journal of Tissue Engineering Research 2025;29(10):2052-2060
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.
2.Influence of corneal fluorescein sodium staining on test results of iTrace visual function analyzer
Xin YIN ; Qingyan LIU ; Xiao SHAO ; Min XUE ; Yao LU ; Shuying MA ; Chunsheng SHI
International Eye Science 2025;25(4):680-684
AIM: To investigate the impact of corneal fluorescein sodium(NaF)staining on the examination results of iTrace visual function analyzer(iTrace).METHODS: Prospective cohort study. Totally 100 patients(100 eyes)with ametropia who visited the outpatient department of Anhui Eye Hospital from April to November 2024 were recruited. They were divided into an experimental group and a control group, with 50 patients(50 eyes, and only the right eyes were selected for inclusion)in each group. In the experimental group, corneal staining was performed using fluorescein sodium staining test strips, while in the control group, 1 drop of 0.9% normal saline was instilled into the eyes. The iTrace examination was conducted before the intervention and at 5, 10, and 20 min after the intervention. The total corneal higher-order aberrations, spherical aberration, coma aberration, trefoil aberration, best sphere value(RO value), asphericity factor(Q value), and corneal vertical refractive power difference(IS value)at each time of examination were recorded and compared.RESULTS: There was no statistically significant difference in the baseline levels between the two groups(all P>0.05). Intra-group comparison revealed that the total higher-order aberrations, spherical aberration, coma aberration, and trefoil aberration measured 5 min after NaF staining in the experimental group were significantly increased compared with those before staining(all P<0.05). Inter-group comparison showed that the changes(differences from the baseline)in the total corneal higher-order aberrations, spherical aberration, coma aberration, and trefoil aberration measured by iTrace 5 min after the intervention in the experimental group were significantly greater than those in the control group(all P<0.05). There was no statistically significant difference in the changes(differences from the baseline)of various iTrace parameters measured at 10 and 20 min after the intervention between the two groups(all P>0.05). There was no statistical significance in the RO value, Q value, and IS value in the two groups(all P>0.05).CONCLUSION: Corneal NaF staining can cause a short-term increase in the wavefront aberration values(total corneal higher-order aberrations, spherical aberration, coma aberration, trefoil aberration)measured by iTrace, and it gradually disappears with the passage of time. However, it has no impact on the measurement of corneal topography parameters(RO value, Q value, IS value).
3.Determination of biological activity of teduglutide by a homogeneous time-resolved fluorescence method
Xiao-ming ZHANG ; Ran MA ; Li-jing LÜ ; Lü-yin WANG ; Ping LÜ ; Cheng-gang LIANG ; Jing LI
Acta Pharmaceutica Sinica 2025;60(1):211-217
In this study, we constructed a GLP-2R-HEK293 cell line and established a method for the determination of the
5.Fast Object Perception in The Subcortical Pathway: a Commentary on Wang et al.’s Paper in Human Brain Mapping (2023)
Hao-Yun MA ; Yu-Yin WEI ; Li-Ping HU
Progress in Biochemistry and Biophysics 2025;52(7):1904-1908
The subcortical visual pathway is generally thought to be involved in dangerous information processing, such as fear processing and defensive behavior. A recent study, published in Human Brain Mapping, shows a new function of the subcortical pathway involved in the fast processing of non-emotional object perception. Rapid object processing is a critical function of visual system. Topological perception theory proposes that the initial perception of objects begins with the extraction of topological property (TP). However, the mechanism of rapid TP processing remains unclear. The researchers investigated the subcortical mechanism of TP processing with transcranial magnetic stimulation (TMS). They find that a subcortical magnocellular pathway is responsible for the early processing of TP, and this subcortical processing of TP accelerates object recognition. Based on their findings, we propose a novel training approach called subcortical magnocellular pathway training (SMPT), aimed at improving the efficiency of the subcortical M pathway to restore visual and attentional functions in disorders associated with subcortical pathway dysfunction.
6.Association between per- and polyfluoroalkyl substances and serum high-sensitivity C-reactive protein levels: Based on the National Health and Nutrition Examination Survey
Shuang MA ; Qian ZHANG ; Huirong DUAN ; Jinzhu YIN ; Tong WANG ; Qian GAO
Journal of Environmental and Occupational Medicine 2025;42(8):900-907
Background High-sensitivity C-reactive protein (hs-CRP) is a sensitive biomarker for cardiovascular disease (CVD) and can independently predict the risk of cardiovascular events. Although the association between per- and polyfluoroalkyl substances (PFAS) exposure and CVD risk has been widely reported, studies on the association between hs-CRP and PFAS remain limited. Objective To investigate the association between PFAS and hs-CRP levels, to provide a scientific basis for early identification and prevention of environment-related cardiovascular events. Methods This study utilized data from the National Health and Nutrition Examination Survey (NHANES) database (2015–2018). Based on predefined inclusion and exclusion criteria, a total of
7.Monitoring results on iodine nutrition status of children in water borne iodine excess areas of Hebei Province from 2018 to 2023
YIN Zhijuan, JIA Lihui, TIAN Shenqian, GAO Xuejie, XU Ning, XU Dong, MA Jing
Chinese Journal of School Health 2025;46(9):1252-1256
Objective:
To investigate the iodine nutrition status of children in water borne iodine excess areas in Hebei Province, so as to provide references for scientific prevention and control of water borne iodine excess hazards.
Methods:
From March to September each year during 2018 to 2023, a cross sectional survey was conducted in 39 water borne iodine excess counties (measured in 2017) from 5 cities (Cangzhou, Hengshui, Xingtai, Handan and Langfang) in Hebei Province. The survey included the detection of iodine content in residents drinking water, the measurement of thyroid volume in children aged 6-12, the detection of salt iodine and urinary iodine. The iodine nutrition status and water iodine distribution of 6-12 year-old children were evaluated from different perspectives such as years, gender, and age. Kruskal-Wallis H- test, Mann-Whitney U test and Chi square test were used for group comparison.
Results:
A total of 38 755 children were surveyed from 2018 to 2023, and 1 270 drinking water samples were tested across the province. The mass volume concentration of iodine in water showed a decreasing trend over the years ( Z= -30.87, P <0.01). Among 38 470 salt samples monitored from children s home, 24 790 were not non iodized salt, with a non iodized salt rate of 64.44%. A total of 31 989 urine samples were collected from children aged 8-10 years, with the median urine iodine was 245.94 μg/L. Comparing the results of urinary iodine in children from different years, the median urinary iodine from 2018 to 2023 were 328.0, 339.3, 267.8, 279.1, 291.3, 186.5 μg/L, respectively, with statistically significant differences ( H= 4 138.40 , P <0.01). Further pairwise comparisons showed that the median urinary iodine of children in 2023 was lower than in all other years ( Z =-51.59 to -11.41, all P <0.01). Among children aged 6-12 years, 1 150 cases of goiter were detected and the rate of goiter was 3.0%; and the goiter rates in boys and girls were 2.8% and 3.1%, with no significant difference between the sexes ( χ 2= 2.76, P >0.05). There were significant differences in the rate of goiter among different years and ages ( χ 2=324.02, 191.61, both P <0.05).
Conclusions
With the progress of water reform in water borne iodine excess areas of Hebei Province, children s iodine nutrition has reduced from excessive state to suitable state. It is necessary to continue to expand the coverage of water based iodine reduction projects, and strengthen the monitoring of iodine nutrition status of key populations in water borne iodine excess areas.
8.Expression and Clinical Significance of MKI67 in Pancreatic Cancer
Hu WANG ; Yanmei YIN ; Haoxuan DU ; Hao CHEN ; Xiaopeng MA ; Aibin DAI ; Kexiang ZHU
Cancer Research on Prevention and Treatment 2024;51(2):91-98
Objectives To explore the expression, biological function, and mechanism of MKI67 in pancreatic cancer and its clinical significance. Methods The expression level, diagnosis, and prognostic value of MKI67 in pancreatic cancer were analyzed using public databases. We also investigated the association between the MKI67 with immune cell infiltration and immune checkpoint molecules. We analyzed the functional pathway enrichment to uncover the possible molecular mechanisms. qRT-PCR and Western blot assay were used to verify the expression of MKI67 mRNA and protein. Immunohistochemistry staining was used to detect the expression of MKI67 in tissue protein. Results The high expression of MKI67 was significantly associated with high histological grades and poor outcomes in pancreatic cancer. High MKI67 expression was correlated with poor prognosis of pancreatic cancer patients (
9.Case observation of viral keratitis caused by SARS-CoV-2
Mengzhen XIE ; Hao ZHANG ; Ke MA ; Hongbo YIN ; Lixiang WANG ; Jing TANG
International Eye Science 2024;24(4):495-499
AIM: To report three cases of viral keratitis caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).METHODS: Slit lamp, intraocular pressure, corneal fluorescence staining, anterior segment photography, in vivo confocal microscopy(IVCM), and routine fundus screening were performed in the three confirmed patients. Treatment involved Ganciclovir, artificial tears and glucocorticoid eye drops.RESULTS: Three patients with SARS-CoV-2 keratitis(SCK)recovered well after standard treatment.CONCLUSION: SARS-CoV-2 keratitis typically presents as corneal subepithelial infiltration and can result in a decrease in corneal subepithelial nerve fiber density and an increase in dendritic cells(DC). Antiviral therapy in combination with glucocorticoid has proven to be effective.
10.Risk Factors and Countermeasures of Occupational Exposure of Medical Personnel under COVID-19 Epidemic
Yang FU ; Junling MA ; Lin WANG ; Mei YIN
Chinese Medical Ethics 2024;35(1):84-89
The COVID-19 is a severe respiratory pathogen infection, showing a distinct "hospital cluster" transmission characteristics. This paper illustrated the concept of occupational exposure and COVID-19. Combined with the actual situation of COVID-19, the infection status of medical personnel in this outbreak was analyzed from three aspects: the transmission risk and infection rate of medical personnel, the clinical characteristics and the undiscovered super-spreader. Through the analysis of the present situation, this paper summarized the possible occupational exposure risk factors of medical personnel in COVID-19 from five aspects: biological occupational risk factors, chemical occupational risk factors, physical occupational risk factors, violence factors and psychological factors. From isolating the source of infection and cutting off the transmission route, the "safety supervisor" mechanism is established to avoid the risks of biological, chemical and physical occupational exposure, from providing professional psychological counseling for medical personnel to reduce their psychological stress, and from improving the relevant legal level to reduce the risk of medical personnel’s violent occupational exposure.


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