Objective To study artificial lumbar intervertebral disc three-dimensional finite element model and its stress state. Methods The three-dimensional finite element models of artificial lumbar intervertebral disc were established by finite element software MSC. MARK. While L4-5 motion segment from young healthy cadaver was created to give the models biomaterial characters. The vertebral disc of L4-5 was replaced by artificial lumbar intervertebral disc to make a model of an artificial disc replacement. Results After three-dimensional finite element models with biomaterial characters of artificial lumbar intervertebral disc and L4-5 motion segment had been created, the stress distribution of artificial lumbar intervertebral disc showed some characteristics as follows:1)The stress exerted in the center of polyethylene slide core and end plates is biggest in all motion states, the next exists at the deviated site while the polyethylene slide core set in motion. 2)The upper surface of polyethylene slide core and end plates bear 2-3 times stress as much as that of the lower surface. 3)The biggest stress exists in the center of polyethylene slide core and end plates during compression in all motion states. Conclusion Establishment of three-dimensional finite element models of artificial lumbar intervertebral disc and analysis of its stress are feasible. The results are reliable.

BACKGROUND: Presently-used artificial intervertebral disk is different greatly from the normal physiological intervertebral disk in structure, material and biological properties and so on. Therefore, stress conduction at corresponding spinal section will have a certain change after the implantation of artificial intervertebral disk.OBJECTIVE: To investigate the stress distribution in small joints of normal intervertebral disk group, vertebral extirpation group and artificial lumbar intervertebral disk group with three-dimensional element method in order to discuss exploratorily the influence of the implantation of artificial lumbar intervertebral disk on the stress distribution in small joints.DESIGN: Observative and comparison experiment.SETTING: Orthopedic Department, Third Affiliated Hospital and Second Affiliated Hospital, Sun Yat-sen University; Biomechanical Laboratory in Southern Medical University.PARTICIPANTS: Spinal specimen collected from the healthy people who died in accidenct without any spinal illness (donated by their family member) was used to establish three kinds of three-dimensional element models of normal intervertebral disk, artificial intervertebral disk and vertebral extirpation as experimental subjects.METHODS: Finite element MSC.MARK software was used to establish normal intervertebral disk model with height of 10.00 mm, cross sectional area of 1300.00 mm2, and vertebral pulp cross sectional area of 495.8 mm2;in the model of vertebral pulp extirpation,the intrinsic pressure of vertebral pulp was zero; and in the three dimensional models of artificial lumbar intervertebral disk and L4-5 movement segment , the small joints were about 10.53 mm high with width of 13.37 mm and auricular area of 135 mm2.Then lumbar movement was simulated for the study of the stress distribution in small joint.MAIN OUTCOME MEASURES: Comparison of the stress in small joints under 6 kinds of states in the above three kinds of intervertebral disk movement model.RESULTS:In vertebral pulp extirpation group, the stress was proved to be the highest at superior edge, posterior middle part, lower edge and anterior middle part of small joints under anteflexion, backward extension, compression, lateroflexion and revolving states, moreover, small joint stress in artificial lumbar intervertebral disk was higher than that in normal intervertebral disk, but obviously lower than that in vertebral pulp extirpation group;however, the small joint of the middle part of artificial lumbar intervertebral disk bore the highest stress under revolving states.CONCLUSION: In contrast with vertebral pulp extirpation group, the small joint stress could be reduced after the implantant of artificial lumbar intervertebral disk, but was still higher than that of normal lumbar intervertebral disk group and the anti-verticity in artificial lumbar intervertebral disk group was markedly lower than that of normal lumbar intervertebral disk group and vertebral pulp ablation group, thus indicating that although presently-used artificial lumbar intervertebral disk possesses most of mechanical functions of normal lumbar intervertebral disk, but is still different from true lumbar intervertebral disk.

BACKGROUND: At present, there are very big differences in structure,material character and biological property between artificial intervertebral disc (AID) and normal physiological intervertebral disc.OBJECTIVE: Three-dimensional finite element method was used to observe and analysis the stress conduction of artificial lumbar intervertebral disc in lumbar motion segment.DESIGN: Single sample observation was designed.SETTING: Department of Orthopaedics, Third Affiliated Hospital, Sun Yat-sen University; Department of Orthopaedics, Second Affiliated Hospital, Sun Yat-sen University; Laboratory of Mechanics, Southern Medical UniversityPARTICIPANTS: It was to employ a vertebral sample without any spinal disorder of a healthy male died due to accidence and a finite element model of AID implantation in vertebral motion segment established with SB Charite Ⅲ AID.METHODS: According to industrial design chart of AID, finite element software MSC.MARK was utilized to establish three-dimensional model of artificial lumbar intervertebral disc. The corpus sample of motion segment of healthy lumbar vertebrae was collected and scanned with spiral CT machine and imaging documents were input in computer to preserve.Geometric model of L4-5 segment was established in three-dimensional coordinate system in ASC.MARK software. The intervertebral disc in L4-5 motion segment model was replaced by AID. It was to ensure the fixation of lower terminal lamina of L5 in the model. 4 Nm moment of force was exerted in anterior flexion, posterior extension, lateral bending and torsion on the sample successively. Finally, force of internodes representing AID was calculated and stress distribution was recorded.MAIN OUTCOME MEASURES: To observe stress distribution of anterior flexion, posterior extension, compression, lateral bending and rotation of AID.RESULTS: Finite element model of artificial lumbar intervertebral disc implanted lumbar motion segment that is in conformity with clinical practice was established. Stress distribution of AID was characterized as:er lamina was the maximum and that in the lower inclined part of slide of slide core and cover lamina was two or three times as same as that of sion, the stress in the center of slide core and cover lamina was the maximum.CONCLUSION: The finite element model of artificial lumbar intervertebral disc implanted lumbar motion segment established is in conformity with the structural character of practical artificial intervertebral disc in morphology, size and motion property, based on which, it is feasible to carry on the experiment on stress distribution of artificial intervertebral disc.

Objective To optimize extraction process of flavonoids from Toosendan Fructus.Methods Three parameters that significantly affect the extraction rate of flavonoids, ratio of material to water, extraction time and ethanol concentration, were taken into consideration for extraction ratio of flavonoids from Toosendan Fructus. Based on the results of single-factor experiment, the extraction parameters of flavonoids from Toosendan Fructus were optimized by Box-Behnken of response surface methodology (RSM).Results The optimum extraction conditions were as follow: material to water ratio was 1:35; extraction time should be 3 h; ethanol concentration was 70%. The extraction ratio was up to 0.587 3% in the optimum extraction conditions.Conclusion The actual value is highly matching the theoretically value of RSM model. The results indicated that this method can rationally optimize extraction process of flavonoids from Toosendan Fructus.

Objective To build a method of mandible 3D model to measure and analysis, then to finish the operation simulation, providing anatomic data to avoiding the complicafious of mandible osteotomy. Methods Using CT data to reconstruct 3D model of mandible with blood vessel and bone, then using Simpleware to measure and analysis, and using Freeform system and an incision method of Boolean to simulation mandible osteotomy safely. Re, tits It was possible to use CT data to rebuild 3D model for 3D measure and analysis for operation simulation. The inferior alveolar artery and never were the main tiasues which went through the madibhilar. The length of mandibular foramen to anterior minus was (19.13±0.66) ram,and the ones to posterior ramus was (18.96± 0.64)mm. The angle of the mandible was (109.70±4.67)°. The rages of the remus for safe operation was (12.62±0.28)mm, and the safe rages about angle of the body and bottom of the mandible was (22.30±4.67)°. There were obvious differences from children to the aged in the mandible physiological and anatomic study. We can use Freeform system to simulate the operation on 3D model. Conclusion It is a new method to build 3D model and use Freefonn system to simulate operation and a new path to communion with patients for a good operation.

Objective The aim of this study was to investigate the differences of the cell ultrastucture of normal mouse hatched blastocysts and their dormant ones cultured in vitro after freezing-thawing, and to explore whether the dor-mant embryos have a better anti-freezing shock property than the normal hatched mouse embryos .Methods By transmis-sion electron microscopy , the ultrastructure of these two types of mouse embryos was observed and analyzed .Results By comparative analysis of their ultrastructure , the results showed that the dormant embryos before freezing are being austerity and with lower energy metabolism at a ‘ground state ’ .After freezing-thawing and culture , their cellular structure seemed to be similar to that of the normal embryos cultured in vitro before freezing.However, after freezing-thawing and culture, the number of mitochondria decreased , the nuclei were loose , and their heterochromatin also increased .Conclusions From the ultrastructural observation , compared with the normal mouse hatched embryos , the cellular state of dormant mouse em-bryos after freezing-thawing is more favorable for material storage and energy metabolism , thus, indicating that they have a better anti-freezing property than normal hatched embryos .

Objective To investigate the relationship of serum melatonin(MLT)and Klotho protein with pro-inflammatory factors and the effect of surgical treatment in patients with primary angle-closure glaucoma(PACG).Methods A total of 149 PACG patients admitted to the Zigong Fourth People's Hospital from June 2018 to June 2021 were selected as the case group,and 149 healthy people who underwent physical examina-tion in the hospital during the same period were selected as the control group.The levels of MLT,Klotho pro-tein,interleukin-6(IL-6),interleukin-1β(IL-1β)and tumor necrosis factor-α(TNF-α)were compared be-tween the two groups.Pearson correlation analysis was used to analyze the correlation between MLT,Klotho protein and pro-inflammatory factors.Univariate and multivariate Logistic regression models were used to an-alyze the influencing factors of surgical treatment.Results Compared with the control group,the levels of MLT and Klotho protein in the case group were decreased(P<0.05),and the levels of IL-1β,IL-6 and TNF-α were increased(P<0.05).Pearson correlation analysis showed that serum MLT and Klotho protein were negatively correlated with the levels of pro-inflammatory factors IL-1β,IL-6,and TNF-α(P<0.05).After 12 months of surgical treatment,30 patients(20.13%)had no effect of surgical treatment(ineffective group).119 patients(79.87%)had effective surgical treatment(effective group).The univariate analysis showed that compared with the effective group,the preoperative intraocular pressure(IOP),proportion of chronic PACG,preoperative best corrected visual acuity,proportion of preoperative Angle adhesion>160° were significantly increased(P<0.05),and the preoperative anterior chamber depth,MLT,and Klotho protein levels were de-creased in the ineffective group(P<0.05).Multivariate Logistic regression analysis showed that elevated pre-operative IOP,chronic PACG,decreased MLT and Klotho levels were independent risk factors for ineffective surgical treatment(P<0.05).Conclusion serum MLT,Klotho protein levels in patients with PACG,closely associated with proinflammatory factor,is the related factors influencing the effect of surgical treatment.

Objective:To investigate the mental health status and psychological intervention needs in community health service staff during the outbreak of COVID-19.Methods:From February 28 to March 2, 2020, a total of 554 questionnaires on the mental health status and psychological intervention needs were collected from community health service staff in Beijing, Zhejiang, Hebei and Shanghai. The mental health was assessed by physical symptoms and GAD-7. The status and effectiveness of psychological intervention was analyzed.Results:The survey found that 19.7% (109/554) of community health service staff needed psychological support. Most psychological supports were received from colleagues′ encouragement (59.6%, 330/554) and internet mental health knowledge (41.2%, 228/554); in contrast, less from group intervention (5.8%, 32/554) and one-on-one counseling (5.6%, 31/554). Higher proportion of staff with anxiety symptoms and physical symptoms needed psychological support than that without symptoms (χ 2=53.41, 71.47), and a higher proportion of responders thought that the existing psychological intervention was not helpful (χ 2=26.89, 17.79), the difference is statistically significant ( P<0.05). Conclusion:It is necessary to strengthen the mental health assessment of community health service staff and give effective psychological intervention according to their needs during the outbreak of COVID-19.

AIM:To evaluate the efficacy of corneal stromal lenses combined with 0.1% cyclosporine A eye drops in patients with Mooren's ulcer and its effect on ocular surface inflammatory factors.METHODS:In this prospective randomized controlled trial, 200 patients(272 eyes)with Mooren's ulcer were enrolled from January 2022 to January 2024. Patients were randomly assigned to receive either corneal stromal lenses alone(control group: 100 patients, 136 eyes)or combined with 0.1% cyclosporine A eye drops(observation group: 100 patients, 136 eyes). All patients were followed up for 3 mo. Clinical efficacy, visual acuity improvement, recovery time, pain score, complications, and tear levels of interleukin(IL)-1β, IL-6, and tumor necrosis factor-α(TNF-α)were compared between the two groups.RESULTS:A total of 196 patients(268 eyes)completed follow-up, with 2 cases(2 eyes)lost to follow-up in each group and a lost to follow-up rate of 2.0%. The observation group showed a higher total effective rate(95.5% vs 83.6%, P<0.05). Postoperative best corrected visual acuity(LogMAR)of the observation group was significantly better than that of the control group(0.42±0.15 vs 0.65±0.18, P<0.001). Epithelial(5.24±1.15 vs 7.86±1.43 d)and stromal recovery(12.35±2.46 vs 16.72±3.15 d)were faster in the observation group(both P<0.001). Pain scores and complication rates of the observation group were lower than those of the control group(both P<0.001). Both groups showed reduced tear IL-1β, IL-6, and TNF-α levels postoperatively, with greater reductions in the observation group(P<0.001).CONCLUSION: Corneal stromal lenses combined with 0.1% cyclosporine A eye drops provide superior outcomes for Mooren's ulcer by enhancing visual recovery, accelerating corneal healing, reducing pain, and lowering complications, potentially through inhibition of ocular surface inflammatory factors.

Objective:To understand the relationship between lipid accumulation product (LAP) and hyperuricemia in physical examination population.Methods:This was a cross-sectional study. The analysis was based on baseline data from a retrospective cohort study. Total of 44 294 people who received physical examination in the Health Management Center of Xiangya Hospital of Central South University from January to December 2012 were selected as subjects with whole-group sampling method. All the subjects aged ≥18 years with complete study variables. The minimum waist circumference of the subjects was calculated to determine the criteria for calculating LAP in those population. With LAP as the observed variable and hyperuricemia as the outcome variable, LAP was divided into four groups according to the interquartile interval (Q 1-Q 4 groups): group Q 1<10.56 cm·mmol/L, 10.56 cm·mmol/L≤Q 2<20.79 cm·mmol/L, 20.79 cm·mmol/L≤Q 3<38.94 cm·mmol/L, Q 4≥38.94 cm·mmol/L. Five models were constructed with logistic regression analysis. No confounding factors was adjusted in Model 1, model 2 was adjusted for age and gender; and model 3 was further adjusted for body mass index, hypertension, hyperlipidemia, creatinine and glomerular filtration rate; model 4 was further adjusted education level, occupation, health insurance, smoking, drinking, diet scores and physical exercise; model 5 was further adjusted the family history of gout, diabetes and hypertension. And the relationship between different LAP levels and hyperuricemia was analyzed. Results:In this study, the minimum waist circumference in the physical examination population was 58 cm and 53 cm for men and women, respectively. The total incidence of hyperuricemia was 13.4% in this population, 5.94% for women and 19.40% for men. When the confounding factors were not adjusted (model 1), the risk of hyperuricemia in women′s LAP Q 2 to Q 4 groups was 1.76 times (95% CI: 1.42-2.17), 5.08 times (95% CI: 4.20-6.14) and 12.58 times (95% CI: 10.43-15.18), and it was 1.68 times (95% CI: 1.43-1.96), 2.74 times (95% CI: 2.36-3.18), and 5.32 times (95% CI: 4.62-6.14) in men, respectively. After gender stratification and adjustment for confounding factors (model 5), the risk still existed, compared with that in Q 1 group of LAP, the risk of hyperuricemia in women in Q 4 group was 8.28 times higher (95% CI: 2.50-27.38) and 3.31 times higher in men (95% CI: 1.57-6.95). Conclusion:The risk of hyperuricemia in health examination population increases with LAP, especially in women.