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:Trigeminal neuralgia(TN)is a severe chronic neuropathic pain that mainly affects the distribution area of the trigeminal nerve with limited treating efficacy.There are numerous treatments for TN,but currently the main clinical approach is to suppress pain by carbamazepine(CBZ).Brain-derived neurotrophic factor(BDNF)is closely related to chronic pain.This study aims to determine the effects of CBZ treatment on BDNF expression in both the trigeminal ganglion(TG)and serum of TN via a chronic constriction injury of the infraorbital nerve(ION-CCI)rat model. Methods:The ION-CCI models were established in male Sprague-Dawley rats and were randomly divided into a sham group,a TN group,a TN+low-dose CBZ treatment group(TN+20 mg/kg CBZ group),a TN+medium-dose CBZ treatment group(TN+40 mg/kg CBZ group),and a TN+high-dose CBZ treatment group(TN+80 mg/kg CBZ group).The mechanical pain threshold in each group of rats was measured regularly before and after surgery.The expressions of BDNF and tyrosine kinase receptor B(TrkB)mRNA in TGs of rats in different groups were determined by real-time PCR,and the expression of BDNF protein on neurons in TGs was observed by immunofluorescence.Western Blotting was used to detect the protein expression of BDNF,TrkB,extracellular regulated protein kinases(ERK),and phospho-extracellular regulated protein kinases(p-ERK)in TGs of rats in different groups.The expression of BDNF in the serum of rats in different groups was detected by enzyme-linked immunosorbent assay(ELISA). Results:The results of mechanical pain sensitivity showed that there was no significant difference in the mechanical pain threshold in the right facial sensory area of the experimental rats in each group before surgery(all P>0.05).From the 3rd day after operation,the mechanical pain threshold of rats in the TN group was significantly lower than that in the sham group(all P<0.01),and the mechanical pain threshold of rats in the TN+80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 CBZ mg/kg group was higher than that in the TN group(all P<0.05).The BDNF and TrkB mRNA and protein expressions in TGs of rats in the TN group were higher than those in the sham group(all P<0.05),and those in the TN+80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 mg/kg CBZ group were lower than the TN group(all P<0.05).The p-ERK levels in TG of rats in the TN+80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 mg/kg CBZ group were significantly decreased compared with the TN group(all P<0.05).The BDNF and neuron-specific nuclear protein(NeuN)were mainly co-expressed in neuron of TGs in the TN group and they were significantly higher than those in the sham group(all P<0.05).The co-labeled expressions of BDNF and NeuN in TGs of the TN+ 80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 mg/kg CBZ group were lower than those in the TN group(all P<0.05).The results of ELISA showed that the level of BDNF in the serum of the TN group was significantly higher than that in the sham group(P<0.05).The levels of BDNF in the TN+80 mg/kg CBZ group,the TN+40 mg/kg CBZ group,and the TN+20 mg/kg CBZ group were lower than those in the TN group(all P<0.05).Spearman correlation analysis showed that the BDNF level in serum was negatively correlated with mechanical pain threshold(r=-0.650,P<0.01). Conclusion:CBZ treatment can inhibit the expression of BDNF and TrkB in the TGs of TN rats,reduce the level of BDNF in serum of TN rats and the phosphorylation of ERK signaling pathway,so as to inhibit TN.The serum level of BDNF can be considered as an indicator for the diagnosis and prognosis of TN.

  Objective  To investigate the occurrence of chronic postsurgical pain (CPSP) among patients with preoperative COVID-19, and further analyze the risk factors for CPSP.  Methods  This study was a ambispective cohort study, with subjects from a completed cohort study with follow-up. We included the clinical data of the patients with preoperative COVID-19 who underwent surgery at Peking Union Medical College Hospital from December 1, 2022 to February 28, 2023. Follow-up was conducted up to 6 months postoperatively, with the primary outcome being CPSP. Multivariate Logistic regression analysis was used to analyze the correlation between COVID-19-related exposure indicators and CPSP.  Results  A total of 4117 surgical patients were included, all of whom had preoperative COVID-19. Among them, 4002 cases had mild symptoms during the acute phase, 62 cases had severe symptoms, and 53 cases were critically ill. At 6th month postoperatively, 1298 cases (31.53%) had long COVID-19 syndrome, and the incidence of CPSP was 5.59% (95% CI: 4.88%-6.28%). After adjusting for confounding factors including age, gender, comorbidities, anesthesia method, and type of surgery, multivariate Logistic regression analysis revealed that critically ill COVID-19 during the acute phase (aOR=3.35, 95% CI: 1.48-7.62, P < 0.001) and presence of long COVID-19 syndrome postoperatively (aOR=2.50, 95% CI: 1.90-3.29, P < 0.001) were associated with CPSP.  Conclusions  It is clear for the first time that critically ill COVID-19 during the acute phase and the presence of long COVID-19 syndrome postoperatively are the risk factors for CPSP among patients with preoperative COVID-19.

Objective:To investigate the clinical value of ultrasound in evaluating pharyngeal dysphagia after stroke.Methods:Thirty stroke survivors with dysphagia formed the patient group, and 30 healthy persons formed the healthy group. All received pharyngeal ultrasound examinations by the same sonographer. The maximum distance from the hyoid bone to the mandible, the minimum distance, and the required time were measured or calculated. The hyoid bone′s motion, distance shortening rate, geniohyoid muscle activity, activity time, and activity speed were calculated. The differences in each value were compared, and the values were correlated with the videofluoroscopic swallowing study (VFSS) score using Spearman rank correlation. Receiver operating characteristics curves (ROC curves) were used to evaluate the value of hyoid bone and geniohyoid muscle activity for evaluating the severity of pharyngeal swallowing disorders after a stroke.Results:The average range of activity, activity time, and activity speed of the geniohyoid muscle in the patient group were all significantly different from the healthy group′s averages. The hyoid bone′s range of activity, activity time, activity speed, and the rate of shortening of its distance from the mandible were also significantly different, on average. The patients′ VFSS grades correlated strongly with the activity of the geniohyoid muscle, moderately with the geniohyoid muscle′s speed, and weakly with the duration of hyoid bone activity.Conclusion:The speed of geniohyoid muscle activity and hyoid bone activity time can be used to evaluate the severity of pharyngeal swallowing dysfunction after a stroke. Geniohyoid muscle activity is the best indicator.

Objective:To investigate the immunophenotypic and molecular biological characteristics of patients with elevated serum alpha-fetoprotein (AFP) and enteroblastic differentiated gastric adenocarcinoma (GAED).Methods:The clinicopathological data of 13 patients with elevated serum AFP and GAED admitted to Shanxi Cancer Hospital from 2018 to 2020 were collected. Immunohistochemistry (IHC) and next-generation sequencing (NGS) were used to analyze the immune markers and molecular biological characteristics of the pathological tissues of the patients. Kaplan-Meier method and log rank test were used for survival analysis.Results:Among the 13 patients with GAED, 12 were male and 1 was female, aged 41-70 years, with a median age of 64 years. The lesions were mainly located in the gastric antrum (5 cases) and gastric body (4 cases). IHC results showed that the tumor embryonic protein (AFP, SALL4, GPC3), intestinal epithelial differentiation protein (CDX-2, CD10), and some original intestinal epithelial phenotype markers (OCT3/4, Claudin6) were expressed in the tumor tissues. Combined application of multiple markers can reduce the rate of missed diagnosis. Among the 13 patients, 12 had at least one mutation (1 mutation: 1 case, 2-5 mutations: 3 cases, 6-15 mutations: 8 cases), and 1 case was not detected. The gene with the highest mutation frequency was TP53 (10 cases), and other mutant genes included EPHB1 (3 cases), ATRX (2 cases), EPHA5 (2 cases), GATA3 (2 cases), LRP1B (2 cases) and MAP2K4 (2 cases) were also detected. Three of the 13 patients had structural variations, which were C14orf177- GNAS, AIM1- FGFR3, and EPHA6- ROS1 gene rearrangements. All 13 patients had copy number variation, and 11 patients had copy number variation of more than 2 genes. The common amplification genes were IRS2 (5 cases), PTEN (5 cases), GNAS (4 cases), CCNE1 (3 cases), CEBPA (3 cases), PCK1 (3 cases) and ERBB2 (2 cases). The common deletion genes were SOX2 (5 cases) and MYC (5 cases). Among the 13 patients, 4 died, and 2 of the dead patients had liver metastasis. There were 4 patients with disease-free survival and 5 patients with disease progression, including 3 cases of abdominal metastasis and 2 cases of liver metastasis. The 3-year survival rate of patients was 65.9 %, and the 3-year progression-free survival rate was 30.7 %. Gene LRP1B point mutation was associated with poor prognosis ( P＜0.001). There was no significant improvement in the prognosis of patients treated with immunotherapy compared with those treated with chemotherapy alone ( P=0.595), but the prognosis of patients treated with postoperative chemotherapy or postoperative chemotherapy plus immunotherapy was better than that of patients treated with surgery alone ( P＜0.05). Conclusions:Elevated serum AFP with GAED is a highly invasive tumor with unique molecular characteristics, often accompanied by multiple molecular events. TP53 mutation is the most common type of gene mutation. In addition, some cases are accompanied by HER2 amplification and gene rearrangement.

Objective:To investigate the immunophenotypic and molecular biological characteristics of patients with elevated serum alpha-fetoprotein (AFP) and enteroblastic differentiated gastric adenocarcinoma (GAED).Methods:The clinicopathological data of 13 patients with elevated serum AFP and GAED admitted to Shanxi Cancer Hospital from 2018 to 2020 were collected. Immunohistochemistry (IHC) and next-generation sequencing (NGS) were used to analyze the immune markers and molecular biological characteristics of the pathological tissues of the patients. Kaplan-Meier method and log rank test were used for survival analysis.Results:Among the 13 patients with GAED, 12 were male and 1 was female, aged 41-70 years, with a median age of 64 years. The lesions were mainly located in the gastric antrum (5 cases) and gastric body (4 cases). IHC results showed that the tumor embryonic protein (AFP, SALL4, GPC3), intestinal epithelial differentiation protein (CDX-2, CD10), and some original intestinal epithelial phenotype markers (OCT3/4, Claudin6) were expressed in the tumor tissues. Combined application of multiple markers can reduce the rate of missed diagnosis. Among the 13 patients, 12 had at least one mutation (1 mutation: 1 case, 2-5 mutations: 3 cases, 6-15 mutations: 8 cases), and 1 case was not detected. The gene with the highest mutation frequency was TP53 (10 cases), and other mutant genes included EPHB1 (3 cases), ATRX (2 cases), EPHA5 (2 cases), GATA3 (2 cases), LRP1B (2 cases) and MAP2K4 (2 cases) were also detected. Three of the 13 patients had structural variations, which were C14orf177- GNAS, AIM1- FGFR3, and EPHA6- ROS1 gene rearrangements. All 13 patients had copy number variation, and 11 patients had copy number variation of more than 2 genes. The common amplification genes were IRS2 (5 cases), PTEN (5 cases), GNAS (4 cases), CCNE1 (3 cases), CEBPA (3 cases), PCK1 (3 cases) and ERBB2 (2 cases). The common deletion genes were SOX2 (5 cases) and MYC (5 cases). Among the 13 patients, 4 died, and 2 of the dead patients had liver metastasis. There were 4 patients with disease-free survival and 5 patients with disease progression, including 3 cases of abdominal metastasis and 2 cases of liver metastasis. The 3-year survival rate of patients was 65.9 %, and the 3-year progression-free survival rate was 30.7 %. Gene LRP1B point mutation was associated with poor prognosis ( P＜0.001). There was no significant improvement in the prognosis of patients treated with immunotherapy compared with those treated with chemotherapy alone ( P=0.595), but the prognosis of patients treated with postoperative chemotherapy or postoperative chemotherapy plus immunotherapy was better than that of patients treated with surgery alone ( P＜0.05). Conclusions:Elevated serum AFP with GAED is a highly invasive tumor with unique molecular characteristics, often accompanied by multiple molecular events. TP53 mutation is the most common type of gene mutation. In addition, some cases are accompanied by HER2 amplification and gene rearrangement.

Objective:To investigate the effects of carnosine on lipopolysaccharide(LPS)-induced inflammasome activation and pyroptosis in microglia,and to clarify its mechanism.Methods:Activation model of microglia was established by LPS(10 ng/ml).CCK-8 assay was used to detect cell activity of microglia treated with different concentrations of carnosine(0.2,1,5,20,50 mmol/L)for 6 h,and the cell activity of microglia pretreated with different concentrations of carnosine for 0.5 h and then stimulated with LPS for 6 h,to screen a suitable concentration.Then microglia were divided into control group,carnosine group(5 mmol/L),LPS group,and LPS+carnosine group:cell morphological changes in each group were observed under an inverted phase contrast microscope;levels of IL-1β,TNF-α and IL-6 in microglial culture medium were measured by ELISA;propidium iodide(PI)staining was used to detect py-roptotic cells;immunofluorescence was used to observe protein expression of Nod-like receptor protein 3(NLRP3).Results:Com-pared with control group,cell viability of microglia in LPS group was significantly decreased(P<0.01),the shape of microglia was mostly"amoeboid",levels of IL-1β,TNF-α and IL-6 in microglial culture medium were significantly increased(P<0.01),the posi-tive rate of PI and the number of NLRP3 positive cells were significantly increased(P<0.01).Compared with LPS group,cell viability of microglia in LPS+carnosine group was significantly increased(P<0.01),the number of"amoeboid"microglia was decreased,levels of IL-1β,TNF-α in microglial culture medium were significantly decreased(P<0.01),and the level of IL-6 was decreased(P<0.05),the positive rate of PI and the number of NLRP3 positive cells were both significantly decreased(P<0.01).Conclusion:Carnosine can inhibit LPS-induced microglia activation and inflammasome activation,thereby inhibiting cell pyroptosis and the release of inflammato-ry factors.

Background Steel workers are exposed to occupational hazardous factors such as dust, noise, and heat, and often work in shifts, making them prone to sleep disorders. Objective To explore potential influencing factors of sleep disorders among workers in a steel enterprise in Gansu Province, and provide a basis for reducing the risk of sleep disorders among them. Methods From January to March 2022, a self-made questionnaire combined with the Pittsburgh Sleep Quality Index (PSQI) were used to investigate the employees of a steel enterprise in Gansu Province. According to their PSQI scores, they were divided into a normal sleep group and a sleep disorder group. The general demographic variables of the two groups were balanced by 1∶1 propensity score matching (PSM). Multiple logistic regression was used to analyze the contributing factors of sleep disorders. Restricted cubic spline (RCS) model was used to analyze potential dose-response relationship between weekly working hours and sleep disorders. Results The prevalence of sleep disorders in the steel workers was 48.06% (6029/12544). After PSM, 5847 pairs were successfully matched, and the distributions of matched variables were well balanced between the two groups. The results of multiple logistic regression showed that hypertension (OR=1.39, 95%CI: 1.24, 1.56), diabetes mellitus (OR=1.34, 95%CI: 1.07, 1.66), three-shift system (OR=1.26, 95%CI: 1.12, 1.41), dust exposure (OR=1.14, 95%CI: 1.01, 1.29), noise exposure (OR=1.23, 95%CI: 1.09, 1.39), heat exposure (OR=1.16, 95%CI: 1.04, 1.29), and work injury (OR=1.22, 95%CI: 1.02, 1.46) increased the risk of sleep disorders. Compared with workers with < 10 years of service, those with 10-20 years (OR=1.31, 95%CI: 1.19, 1.44), 20-30 years (OR=1.34, 95%CI: 1.19, 1.52), and ≥30 years of service (OR=1.35, 95%CI: 1.19, 1.53) had a higher risk of sleep disorders. Compared with non-exercise workers, the risk of developing sleep disorders was lower in workers with occasional exercise (OR=0.61, 95%CI: 0.56, 0.66) and regular exercise (OR=0.55, 95%CI: 0.49, 0.62). The RCS model showed that the weekly working hours and sleep disorders in the steel workers showed a nonlinear dose-response relationship (P<0.05 for overall trend, P<0.05 for nonlinear test). The relationship between weekly working hours and sleep disorders showed a "U" shaped distribution, with a significant increase in the risk of sleep disorders when the weekly working hours exceeded 49 h. Conclusion The non-occupational influencing factors of sleep disorders of employees in the steel enterprise include hypertension, diabetes, physical exercise, and occupational influencing factors include length of service, weekly working hours, shifts, dust exposure, noise exposure, heat exposure, and work injuries. It is recommended to consider both occupational and non-occupational factors to formulate appropriate sleep disorder prevention and control measures for steel employees to reduce the risk of sleep disorders.

Objective:To examine the relationship between sarcopenia and DNA methylation in the promoter of the growth differentiation factor 15(GDF15)gene in elderly individuals.Methods:This cross-sectional study collected data from 865 elderly individuals aged 65 years and above who underwent physical examination at the Yuetang Town Community Medical Center in Yangzhou City between May and September 2020.The verification set included 431 males and 434 females with an age range of 65-100 years and a mean age of(76.0±5.9)years.The diagnosis of sarcopenia was based on the consensus diagnostic criteria of the Asian Sarcopenia Working Group in 2019.The study included 295 cases in the non-sarcopenia group and 470 cases in the sarcopenia group.The study selected 50 non-sarcopenia patients and 50 age-gender matched sarcopenia patients as the explore set for DNA methylation sequencing of the GDF15 gene.The sequencing results were then verified using the methylation-specific polymerase chain(PCR)method in the verification center.Additionally, serum GDF15 levels were detected using the enzyme-linked immunosoradsorption method.The study analyzed the correlation between GDF15 methylation levels, serum GDF15 levels, and sarcopenia.Results:The study found that individuals with sarcopenia had lower levels of body mass index(BMI), appendicular skeletal muscle mass(ASMI), grip strength, and gait speed in both the discovery and validation sets compared to those without sarcopenia( P<0.05). Additionally, the DNA methylation of GDF15 was found to be lower in the sarcopenic group compared to the non-sarcopenic group[93.7%(79.6%, 98.0%) vs.97.7%(95.3%, 99.0%), Z=-9.294, P<0.01]. The results of the correlation analysis indicate a positive relationship between the methylation level and appendicular skeletal muscle mass( r=0.206, P<0.01), grip strength( r=0.297, P<0.01), and gait speed( r=0.383, P<0.01). Conversely, there was a negative correlation between the methylation level and serum GDF15 level( r=-0.249, P<0.05). The study conducted ROC analysis to determine the predictive ability of GDF15 methylation for sarcopenia found that the area under the curve was 0.700 with a cut-off score of 92.7%.Furthermore, binary regression analysis revealed that low GDF15 methylation( OR=1.136, 95% CI: 1.098~1.175, P<0.01)was linked to a higher risk of sarcopenia, even after adjusting for age, sex, and BMI.The serum GDF15 level was higher in the sarcopenic group compared to the non-sarcopenic group[(0.665±0.432)pg/L vs.(0.465±0.211)pg/L( t=-2.452, P<0.05)]. Additionally, it was observed that the methylation of GDF15 was negatively correlated with the serum GDF15 level( r=-0.249, P<0.05). Conclusions:A low level of GDF15 methylation has been found to be linked with a higher risk of sarcopenia, suggesting that measuring GDF15 methylation could potentially serve as a biomarker for diagnosing sarcopenia.

Objective:To collect data on urinary flow rate in the elderly female population across the country and to analyze the range of reference values.Methods:This study enrolled 333 subjects from July 2020 to June 2022.The study implementation process was divided into two steps.In the first step, subjects completed an electronic questionnaire, which included basic information about the subject, a short form for urinary incontinence, and a scoring form for the symptoms of overactive bladder syndrome.In the second step, the staff introduced the use of a mobile uroflowmetric device and distributed the instrument and materials.Uroflow rate data were automatically uploaded to a cloud database via the mobile phone.Subsequently, two or more physicians specializing in urinary control performed Uroflow rate-qualifying screenings and conducted statistical analyses.Results:A total of 333 subjects were enrolled in the study, and the researchers collected 1375 qualified urine flow rate records using a mobile urine flow rate instrument.The age of the subjects ranged from 60 to 84 years, with a mean age of 69 years.The reference ranges for urinary flow rate were found to be 24.8-26.2 s, with a mean urinary flow rate of 12.2-12.9 ml/s, a maximum urinary flow rate of 22.2-23.4 ml/s, and a time to peak of 8.5-9.7 s. The study observed a tendency for both maximal and mean urinary flow rates to decrease in older women as their age increased(Pearson correlation coefficient: -0.1, P<0.001). Conclusions:The uroflow rate of older women decreases with aging.Specifically, the average uroflow rate of women over 80 years old is lower than that of other age groups.This study aims to establish normal uroflow parameters for uroflowmetry in healthy older women in China.