BACKGROUND:The healing of mandibular fractures after rigid internal fixation is influenced by many factors,including the material of the bone plate,fracture site,and bone density of the patient.However,there are relatively few studies on the relationship between the stability of mandibular fracture fixation in different bone qualities and they lack a scientific basis. OBJECTIVE:To analyze the stability of fixation of mandibular fractures with different bone qualities with bioabsorbable plates and miniature titanium plates by finite element analysis. METHODS:Three-dimensional finite element models of class Ⅰ-Ⅳ mandibular fractures were developed according to the bone quality classification method proposed by ZARB and LEKHOLM.The fractures at the median mandibular symphysis,mandibular body,and mandibular angle were simulated under different bone qualities.Bioabsorbable bone grafting plates(or miniature titanium plates)were placed at each fracture site for fixation and to simulate the state of healthy side occlusion.Finite element analysis on the model was used to analyze the relative displacement of the fracture segments and the stress distribution of fixators. RESULTS AND CONCLUSION:(1)The maximum stress value during fixation with titanium plates increased gradually with the increase of bone class,in which the maximum stress value of titanium plates was the highest in the mandibular body class Ⅳ bone group,which was 382.74 MPa and 96.11 MPa in the miniature titanium plate and bioabsorbable plate groups.The results for mandibles of the same bone type showed that the maximum stress value of titanium plates was much higher than that of bioabsorbable plates.(2)For fractures of the median middle of the mandible in types Ⅲ and Ⅳ,the displacement of the fracture breaks at the fixation site was large and exceeded the limiting value of bone healing(>150 μm),regardless of whether the fixation was performed with a miniature titanium plate or a bioabsorbable plate.For type Ⅳ mandibular fractures,the fracture end displacement in the bioabsorbable plate group exceeded the healing limit value,and the fracture end displacement in the miniature titanium plate group was close to the healing limit value.Under the same bone quality and fracture site,the fracture displacement of the miniature titanium plate group was smaller than that of the bioabsorbable plate group.(3)The results showed that the strength and stiffness of the two internal fixations were sufficient to support bone healing of fractures at three sites of the types Ⅰ-Ⅳ mandible,and the fixation stability of the bioabsorbable plate was almost the same as that of the miniature titanium plate,which could provide early healing conditions for fractures.Mandibular bone type should be taken into consideration in the treatment of mandibular fracture.The higher the mandibular bone grade,the worse the stability of fracture fixation,and the more likely the complications such as poor bone healing will occur after surgery.

BACKGROUND:Increasing evidence supports the association between different exercise intensities and the risk of osteoarthritis,but this may be affected by confounding and reverse causality,and the conclusions have not been unified. OBJECTIVE:To explore the causal association between different exercise intensities and osteoarthritis using Mendelian randomization method. METHODS:Data from genome-wide association studies associated with different exercise intensities were selected,and instrumental variables were screened with a threshold of P＜5×10-8.Causal associations between exposure and risk of outcome were assessed using five analysis methods of Mendelian randomization with inverse variance weighting as the primary analysis method.Selected instrumental variables were used to assess causal associations between different exercise intensities and osteoarthritis,and sensitivity analyses with inverse Mendelian randomization were performed. RESULTS AND CONCLUSION:In the analysis results of the inverse variance weighting method,low-intensity exercise showed a significant protective effect on knee osteoarthritis[odds ratio(OR)=0.14,95%confidence interval(CI):0.06-0.32,P＜0.001],while sedentary behavior without exercise intensity,such as watching TV,was confirmed to be a risk factor for knee osteoarthritis and hip osteoarthritis(OR=2.24,95%CI:1.74-2.88,P＜0.001;OR=1.34,95%CI:1.01-1.78,P=0.04).Through the reverse Mendelian randomization analysis of osteoarthritis to different exercise intensities,it was found that osteoarthritis was negatively correlated with low-intensity exercise and positively correlated with watching TV.The analysis results show that there is a two-way causal relationship between different exercise intensity and osteoarthritis risk.

AIM: To delineate the specific mutation responsible for retinitis pigmentosa(RP)in a Yi pedigree, and to analyze the correlation of RHO gene mutation with clinical phenotype.METHODS:A comprehensive clinical evaluation was conducted on the proband diagnosed with RP and other familial members, complemented by a thorough ophthalmic examination. Peripheral blood samples were obtained from the proband and familial members, from which genomic DNA was extracte. Subsequent whole exome sequencing(WES)was employed to identify the variant genes in the proband. The identified variant gene was validated through Sanger sequencing, then an in-depth analysis of the mutation genes was carried out using genetic databases to ascertain the pathogenic mutation sites. Furthermore, an exhaustive analysis was performed to delineate the genotype and phenotype characteristics.RESULTS:The RP pedigree encompasses 5 generations with 42 members, including 19 males and 23 females. A total of 13 cases of RP were identified, consisting of 4 males and 9 females, which conforms to the autosomal dominant inheritance pattern. The clinical features of this family include an early onset age, rapid progression, and a more severe condition. The patients were found to have night blindness around 6 years old, representing the earliest reported case of night blindness in RP families. The retina was manifested by progressive osteocytoid pigmentation of the fundus, a reduced visual field, and significantly decreased or even vanished a and b amplitudes of ERG. The combined results of WES and Sanger sequencing indicated that the proband had a heterozygous missense mutation of the RHO gene c.1040C>T:p.P347L, where the 1 040 base C of cDNA was replaced by T, causing codon 347 to encode leucine instead of proline. Interestingly, this mutation has not been reported in the Chinese population.CONCLUSION:This study confirmed that the mutant gene of RP in a Yi nationality pedigree was RHO(c.1040C>T). This variant leads to the change of codon 347 from encoding proline to encoding leucine, resulting in a severe clinical phenotype among family members. This study provides a certain molecular, clinical, and genetic basis for genetic counseling and gene diagnosis of RHO.

AIM: To delineate the specific mutation responsible for retinitis pigmentosa(RP)in a Yi pedigree, and to analyze the correlation of RHO gene mutation with clinical phenotype.METHODS:A comprehensive clinical evaluation was conducted on the proband diagnosed with RP and other familial members, complemented by a thorough ophthalmic examination. Peripheral blood samples were obtained from the proband and familial members, from which genomic DNA was extracte. Subsequent whole exome sequencing(WES)was employed to identify the variant genes in the proband. The identified variant gene was validated through Sanger sequencing, then an in-depth analysis of the mutation genes was carried out using genetic databases to ascertain the pathogenic mutation sites. Furthermore, an exhaustive analysis was performed to delineate the genotype and phenotype characteristics.RESULTS:The RP pedigree encompasses 5 generations with 42 members, including 19 males and 23 females. A total of 13 cases of RP were identified, consisting of 4 males and 9 females, which conforms to the autosomal dominant inheritance pattern. The clinical features of this family include an early onset age, rapid progression, and a more severe condition. The patients were found to have night blindness around 6 years old, representing the earliest reported case of night blindness in RP families. The retina was manifested by progressive osteocytoid pigmentation of the fundus, a reduced visual field, and significantly decreased or even vanished a and b amplitudes of ERG. The combined results of WES and Sanger sequencing indicated that the proband had a heterozygous missense mutation of the RHO gene c.1040C>T:p.P347L, where the 1 040 base C of cDNA was replaced by T, causing codon 347 to encode leucine instead of proline. Interestingly, this mutation has not been reported in the Chinese population.CONCLUSION:This study confirmed that the mutant gene of RP in a Yi nationality pedigree was RHO(c.1040C>T). This variant leads to the change of codon 347 from encoding proline to encoding leucine, resulting in a severe clinical phenotype among family members. This study provides a certain molecular, clinical, and genetic basis for genetic counseling and gene diagnosis of RHO.

Objective: To analyze the influencing factors for anterior tibial artery atherosclerosis among patients with hyperuricemia, so as to provide insights into the prevention of anterior tibial artery atherosclerosis. Methods: Patients aged 18 years and older with hyperuricemia in Dazhou Integrated TCM & Western Medicine Hospital were enrolled as research subjects from 2020 to 2023. Demographic information and blood biochemistry indicators were collected through electronic medical records. Anterior tibial artery atherosclerosis was evaluated by color Doppler ultrasound. Factors affecting anterior tibial artery atherosclerosis among patients with hyperuricemia were analyzed by a multivariable logistic regression model. Results: A total of 1 105 patients with hyperuricemia were surveyed, including 862 males (78.01%) and 243 females (21.99%). There were 918 cases (83.08%) at the ages of 60 years and older, and 457 cases (41.36%) with a course of disease at 10 years and longer. The median level of blood uric acid was 480.79 (interquartile range, 98.28) μmol/L. There were 314 cases (28.42%) with anterior tibial artery atherosclerosis. Multivariable logistic regression analysis showed that body mass index (≥24.0 kg/m2, OR=1.597, 95%CI: 1.185-2.151), long-term smoking history (yes, OR=1.709, 95%CI: 1.153-2.534), diabetes mellitus (yes, OR=1.517, 95%CI: 1.162-1.981), serum uric acid (≥480.79 μmol/L, OR=1.667, 95%CI: 1.131-2.457), serum creatinine (≥97 μmol/L, OR=1.685, 95%CI: 1.155-2.460), fasting blood glucose (≥6.1 mmol/L, OR=1.528, 95%CI: 1.106-2.112), fibrinogen (>4 g/L, OR=1.589, 95%CI: 1.091-2.315) and triglycerides (≥1.7 mmol/L, OR=1.879, 95%CI: 1.226-2.881) were influencing factors for anterior tibial artery atherosclerosis among patients with hyperuricemia. Conclusion Anterior tibial artery atherosclerosis among patients with hyperuricemia is associated with long-term smoking, diabetes mellitus, serum uric acid, serum creatinine, fasting blood glucose, fibrinogen and triglycerides high level.

Objective To systematically evaluate the efficacy and safety of proximal gastrectomy (PG) versus total gastrectomy (TG) for the treatment of Siewert type Ⅱ/Ⅲ adenocarcinoma of the esophagogastric junction (AEG). Methods PubMed, The Cochrane Library, Web of Science, EMbase, CNKI, Wanfang, and VIP databases were searched for literature comparing the efficacy and safety of PG and TG for the treatment of Siewert type Ⅱ/Ⅲ AEG. The search period was from database inception to March 2023. Meta-analysis was performed using Review Manager 5.4 software. Results A total of 23 articles were included, including 16 retrospective cohort studies, 5 prospective cohort studies, and 2 randomized controlled trials. The total sample size was 2 826 patients, with 1 389 patients undergoing PG and 1 437 patients undergoing TG. Meta-analysis results showed that compared with TG, PG had less intraoperative blood loss [MD=−19.85, 95%CI (−37.20, −2.51), P=0.02] and shorter postoperative hospital stay [MD=−1.23, 95%CI (−2.38, −0.08), P=0.04]. TG had a greater number of lymph nodes dissected [MD=−6.20, 95%CI (−7.68, −4.71), P<0.001] and a lower incidence of reflux esophagitis [MD=3.02, 95%CI (1.24, 7.34), P=0.01]. There were no statistically significant differences between the two surgical approaches in terms of operative time, postoperative survival rate (1-year, 3-year, 5-year), and postoperative overall complications (P>0.05). Conclusion PG has advantages in terms of intraoperative blood loss and postoperative hospital stay, while TG has advantages in terms of the number of lymph nodes dissected and the incidence of reflux esophagitis. There is no significant difference in long-term survival between the two surgical approaches.

Objective To systematically evaluate the short-term efficacy and safety of McKeown and Sweet methods in the treatment of esophageal cancer. Methods PubMed, EMbase, The Cochrane Library, Web of Science, Wanfang, VIP, CNKI and Chinese Biomedical Literature database were searched for literature on the short-term efficacy and safety of McKeown and Sweet methods in the treatment of esophageal cancer published from the establishment to May 2023. Newcastle-Ottawa Scale was used to evaluate the quality of researches, and meta-analysis was performed using RevMan5.4. Results A total of 9 articles were included, involving 3687 patients including 1019 in the McKeown group and 2668 in the Sweet group. NOS score was 8-9 points. There were no statistical differences in the age, sex or American Joint Committee on Cancer stage between the two groups (P>0.05). Patients in the McKeown group had longer operative time and hospital stay, more intraoperative blood loss, and higher Eastern Cooperative Oncology Group scores than those in the Sweet group (P<0.05). However, the McKeown operation could remove more lymph nodes (P=0.001). In terms of safety, the incidences of pulmonary complications [OR=2.20, 95%CI (1.40, 3.46), P=0.001] and postoperative anastomotic leakage [OR=2.06, 95%CI (1.45, 2.92), P=0.001] were higher in the McKeown group than those in the Sweet group. In addition, there were no statistical differences between the two groups in the Karnofsky score, cardiac complications, vocal cord injury or paralysis, chylous leakage, or gastric emptying (P>0.05). Conclusion Compared with McKeown, Sweet method has advantages in operation time, intraoperative blood loss and hospital stay, and has lower incidence of postoperative pulmonary complications and anastomotic leakage. However, McKeown has more lymph node dissection.

Objective To design a mobile personnel radiation protection equipment for operation in environments with high radiation such as spent fuel reprocessing plants, to achieve simultaneous protection against γ radiation, neutron radiation, and radioactive aerosol, to reduce the internal and external exposure dose of radioactive workers, and to meet the requirement of operation for two hours. Methods The core parts of the mobile personnel radiation protection equipment included a shielding chamber and a respiratory maintenance system. An automated chassis was used for the movement and lifting of the shielding chamber. MCNP software was used to simulate and calculate the protective effects of shielding chamber made of different materials and material thicknesses. Experimental verification of the shielding chamber design was conducted. Mathematical models were established to describe the variations in the content of various gases in the chamber with personnel operation time. A respiratory maintenance system, a harmful gas absorption device, and an automated mobile chassis were designed. Results The shielding chamber made of polyethylene with a thickness of 80 mm achieved an 80% neutron shielding rate. The respiratory maintenance system could support workers for 2 hours of operation inside the equipment. The mobile chassis allowed operation of the equipment with one person. Conclusion This mobile personnel radiation protection equipment can solve the problem in simultaneous protection against γ radiation, neutron radiation, and radioactive aerosol. The equipment can provide radiation protection for radioactive workers, reduce exposure dose, and reduce personnel burden. This system provides technical means for the operation and maintenance of equipment in high-radiation sites such as spent fuel reprocessing plants.

Objective This study aimed to investigate the effect of stage Ⅰ comprehensive cardiac rehabili-tation in patients with acute ST elevation myocardial infarction(STEMI)after emergency percutaneous coronary intervention(PCI).Methods A total of 72 patients with acute ST-segment elevation myocardial infarction combined with PCI admitted to the Department of Cardiovascular Medicine of Beijing Electric Power Hospital of State Grid Corporation from June 2021 to June 2022,which were selected as the research objectsand divided into control group and observation group randomly(36 cases in each group).The control group was treated with routine nursing and health education,and the observation group with stage Ⅰ comprehensive cardiac rehabilitation,including initial assessment(cardiovascular comprehensive assessment),exercise training(exercise training and breathing train-ing),daily activity suggestions and health education,discharge assessment(six-minute walking test and Barthel index assessment).The score of Barthel index(BI)at discharge,the 6-minute walking test distance(6MWD)at discharge,the incidence of major adverse cardiovascular event(MACE)during hospitalization and within one month of discharge,and the length of stay were compared between the two groups.Results After intervention,the six-minute walking test distance(6MWD)and Barthel index(BI)score in the observation group were better than those in the control group,the difference was statistically significant(P<0.05).The incidence of major adverse cardiovascular events(MACE)during hospitalization and one month after discharge was lower in the observation group than in the control group,and the difference was statistically significant(P<0.05).The length of hospital-ization in observation group was lower than that in control groupbut there was no statistical difference(P>0.05).Conclusion The application of phase Ⅰ comprehensive cardiac rehabilitation training in patients with acute ST-segment elevation myocardial infarction combined with emergency PCI could improve the patients'exercise ability,improve their ability of daily activity,reduce the incidence of major adverse cardiovascular events(MACE)in the early stage of the disease,facilitate the patients to return to their families and society as soon as possible,and improve their quality of life.It has high clinical application value.

BACKGROUND:Previous studies have shown that human dental pulp stem cells have good osteogenic differentiation potential and are potential seed cells in bone tissue engineering,and the effect of recombinant human growth hormone on the proliferative osteogenic differentiation of human dental pulp stem cells is still unclear. OBJECTIVE:To explore the effect of recombinant human growth hormone on the proliferation and osteogenic differentiation of human dental pulp stem cells. METHODS:Human dental pulp stem cells were isolated and cultured by tissue block culture method.After screening according to the drug concentration gradient,recombinant human growth hormone containing 10,100,250,500,1 000 μg/L was selected as the experimental group,and 0 μg/L without recombinant human growth hormone was selected as the control group.CCK-8 detection reagents were used on days 1,3,5,and 7 after the drug intervention to detect the proliferation of human dental pulp stem cells.Different concentrations(10,100,250,500,and 1 000 μg/L)of recombinant human growth hormone were added to the osteogenesis induction solution to intervene in human dental pulp stem cells.Alkaline phosphatase activity was detected by alkaline phosphatase staining and semi-quantitative analysis on day 7 of mineralization induction.The mRNA expression levels of osteogenic gene type I collagen,osteocalcin and Runt-related transcription factor 2 were detected by fluorescence quantitative RT-qPCR.Alizarin red staining was performed on day 14 of mineralization induction to detect osteogenic mineralized nodules. RESULTS AND CONCLUSION:(1)CCK-8 assay results showed that from the third day of intervention,the 100,250,500,1 000 μg/L recombinant human growth hormone group could promote the proliferation of human dental pulp stem cells compared with the control group(P<0.01).(2)The alkaline phosphatase activity of human dental pulp stem cells in the 100,250,and 500 μg/L recombinant human growth hormone group was significantly increased compared with the control group(P<0.01).The number of alizarin-stained mineralized nodules in human dental pulp stem cells in the 100,250 μg/L recombinant human growth hormone group was significantly increased compared with the control group(P<0.01).Compared with the control group,the mRNA expression of type I collagen and osteocalcin increased in the 250 μg/L recombinant human growth hormone group(P<0.05,P<0.01).mRNA expression of Runt-associated transcription factor 2 increased in the 100 and 250 μg/L recombinant human growth hormone groups(P<0.01).(3)According to the above results,recombinant human growth hormone at a concentration of 250 μg/L is a more suitable concentration to promote the proliferation and osteogenic differentiation of human dental pulp stem cells.