OBJECTIVE: To establish a two-segment vertebrectomy model using the finite element method, and to measure and compare the biomechanical properties of the lower cervical anterior transpedicular root screw (ATPRS) plate system, lower cervical anterior pedicle screw (ATPS) plate system, and lower cervical anterior cervical locked-plate (ACLP) system on this model. METHODS: CT data of the cervical spine (C₀-T₁) from a 34-year-old healthy adult male volunteer were collected. A nonlinear complete model of the lower cervical spine (C₃-C₇) was established using Mimics 10.01 software, based on which the ATPRS fixation model, ATPS fixation model, and ACLP fixation model were constructed respectively. An axial pressure of 75 N and a pure couple moment of 1.5 N·m were applied to C3 to make the model perform flexion-extension, left-right lateral bending, and left-right rotation movements. The range of motion (ROM) and stress distribution of each model under different working conditions were compared. RESULTS: The ROM of the C₄-C₇ segments in the ACLP group, ATPS group, and ATPRS group was reduced to 0.65° (-95.2%), 0.58° (-95.7%), and 0.62° (-95.4%) respectively compared with the intact model during flexion-extension movement;during lateral bending movement, it was reduced to 0.58° (-95.2%), 0.51°(-95.8%), and 0.60° (-95.1%) respectively;during rotation movement, it was reduced to 1.17° (-89.6%), 1.26° (-88.8%), and 1.27°(-88.7%) respectively. In terms of the stress on the titanium mesh graft, the ATPS group and ATPRS group had the maximum load during extension and the minimum load during flexion. Compared with the ACLP group, the stress on the titanium mesh graft in ATPS and ATPRS decreased by (-33.7%) and (-15.8%) in flexion, (-29.4%) and (-13.2%) in extension, (-26.2%) and (-23.4%) in lateral bending, and (-18.8%) and (-5.4%) in rotation, respectively. In terms of bone-screw interface stress, the peak bone stress near the C₇ screw in the ACLP group, ATPS group, and ATPRS group increased by 49.2%, 45.0%, and 47.6% respectively compared with the peak bone stress near the C₄ screw during extension. However, during flexion and lateral bending, there was no significant difference in the peak bone stress near the C₄ and C₇ screws. During rotation, the difference between the peak bone stress near the C₄ screw and that near the C₇ screw showed that in the ACLP group, left rotation (37.6%) was similar to right rotation (36.7%), while in the ATPS group and ATPRS group, left rotation was lower than right rotation. CONCLUSION Compared with the ACLP group, the ATPS group and ATPRS group have greater fixation stiffness and more stable fixation. However, in rotational movement, due to the uneven distribution of fixation stiffness, the stress distribution during torsion is uneven, but it is still better than the ACLP group. This indicates that ATPRS, like ATPS, has good primary stability, providing favorable conditions for bone graft fusion.
Humans ; Finite Element Analysis ; Male ; Cervical Vertebrae/physiopathology* ; Adult ; Biomechanical Phenomena ; Bone Plates ; Bone Screws ; Range of Motion, Articular ; Fracture Fixation, Internal

OBJECTIVE: To compare the biomechanical properties of four internal fixation methods in a lower cervical spine injury model using the finite element method. METHODS: Cervical CT data of a 28-year-old healthy adult male were utilized to establish a finite element model of the normal cervical spine and a lower cervical spine three-column injury model. Four internal fixation methods were then applied to the three-column injury model, resulting in four groups:Group A, anterior cervical locked-plate(ACLP) fixation system model(anterior approach);Group B, posterior cervical pedicle screw fixation model (posterior approach);Group C, combined anterior and posterior cervical pedicle screw fixation model; Group D, Novel composite anterior cervical internal fixation model. A 75 N axial compressive load and a 1.0 N·m pure moment were applied to the upper surface of the cervical spine model to simulate flexion, extension, rotation, and lateral bending movements. The intervertebral range of motion(ROM) and stress distribution of the internal fixators under different motion conditions were compared across all models. RESULTS: Compared with the normal model, the reductions in overall intervertebral ROM for each group under flexion, extension, rotation, and lateral bending were as follows:Group A, 24.04°, 23.12°, 6.24°, and 9.06°;Group B, 24.42°, 24.34°, 6.48°, and 9.20°;Group C, 25.43°, 25.29°, 7.17°, and 9.57°;Group D, 24.75°, 25.5°, 6.71°, and 9.12°. The peak stress values of the internal fixators in each group were:Group A, 53.9 MPa, 79.9 MPa, 61.4 MPa, and 80.3 MPa;Group B, 218.3 MPa, 105.4 MPa, 206.6 MPa, and 186.8 MPa;Group C, 40.8 MPa, 97.2 MPa, 47.1 MPa, and 39.4 MPa;Group D, 93.0 MPa, 144.0 MPa, 64.8 MPa, and 106.3 MPa. CONCLUSION The biomechanical properties of the novel composite anterior cervical internal fixation method are similar to those of the combined anterior-posterior fixation method, and superior to both the anterior cervical ACLP plate-screw fixation and posterior cervical pedicle screw fixation methods.
Humans ; Finite Element Analysis ; Cervical Vertebrae/physiopathology* ; Male ; Biomechanical Phenomena ; Adult ; Fracture Fixation, Internal/methods* ; Range of Motion, Articular

Driven by multiple factors such as policy incentives,enhanced economic capacity of residents,aging popula-tion,and medical system reform,China's rehabilitation industry has been in a rapid development stage where opportunities and challenges coexist.Various rehabilitation hospitals urgently need new development thinking on how to seize the new opportunities for the development of rehabilitation medicine,give full play to the benefits of high-quality rehabilitation medical resources,and deal with the development of rehabilitation institutions under the new situation.Taking the tertiary rehabilitation hospital where the authors work as an example,this paper deeply analyzes the practical difficulties and challenges faced by the development of reha-bilitation hospital under the new circumstance,further explores the construction of a new working mode based on people-oriented and medical-rehabilitation integration.It also briefly summarizes the beneficial experiences and practices in the reform of rehabili-tation service models,and elaborates on the periodic achievement,so as to provide a meaningful reference for the majority of re-habilitation hospitals to plan and practice high-quality development and reform.

Chinese Medical Association and L'Oréal Group jointly launched the "China Skin & Hair Grant" from 2003 to 2018 to support Chinese dermatologists in skin and hair research. This program has not only helped improve the research capability of Chinese dermatologists, but also yielded abundant valuable Chinese population-based clinical and basic research results, and further enabled active academic communication through Chinese and international journals and conferences. This article summarizes main results from skin-related research projects based on program records and publications.

Objective:To explore the association between the variability of triglyceride glucose index (TyG) and the risk of type 2 diabetes mellitus(T2DM).Methods:This study was a retrospective cohort study. A total of 22 929 community-dwelling elderly (aged≥60 years) who received annual health check-ups in Kunshan city of Suzhou Municipality during 2014 to 2021 were enrolled in the study. Fasting triglycerides and blood glucose were measured during annual physical check-ups and the TyG was calculated, the standard deviation of TyG measurements in three consecutive physical check-ups was used as the indicatior of TyG long-term variability. According to the quartile of TyG long-term variability, the study subjects were divided into four groups, namely Q 1 (0-0.14), Q 2 (>0.14-0.22), Q 3 (>0.22-0.33), Q 4 (>0.33-1.90). The outcome variable was the occurrence of T2DM. The relationship between TyG variability and T2DM incidence was analyzed by multivariate Cox regression. Results:In the study cohort 11 518 (50.2%) were females and the mean age was (67.42±5.35) years. By the end of follow-up, 2 934 cases of new T2DM were diagnosed, with an oveall incidence rate of 12.8%. After adjusting for multiple confounders and average TyG, long-term variability of TyG was significantly associated with T2DM risk ( HR=1.83, 95% CI: 1.51-2.20). The risk of T2DM in Q 4 group was significantly higher than that in Q 1 group ( HR=1.33, 95% CI: 1.19-1.47). Kaplan-Meier survival curve showed that long-term variability of TyG was significantly correlated with the cumulative risk of T2DM incidence ( P<0.001). Conclusions:TyG variability is an independent risk factor for T2DM, suggesting that attention should be paid not only to specific time-point TyG levels but also to TyG fluctuation for early identification of T2DM risk.

Objective:To investigate the hemodynamic changes of the main arteries and veins of the extremities and the heart in patients with hypertrophic scar secondary to extensive burns after pressure treatment, and to analyze the relevant mechanisms.Methods:A retrospective before-after self-control study was conducted. From January 2017 to February 2022, 37 patients with hypertrophic scar secondary to extensive burns who met the inclusion criteria were hospitalized in the Burn Rehabilitation Department of Guangdong Industrial Injury Rehabilitation Hospital, including 25 males and 12 females, aged 23-52 years. The patients were admitted to the hospital within 12 weeks after wound healing, and within one week after admission, rehabilitation therapists, occupational therapists, and tailors custom-made pressure products such as full-body pressure garment, pressure pants, vests, split finger gloves, split finger socks, hoods, and plastic collars, with the pressure at each part maintained at 2.67-4.00 kPa when wearing. Before the first treatment with pressure products (hereinafter referred to as before pressure treatment) and at 1 h of the first treatment with pressure products (hereinafter referred to as 1 h of pressure treatment), color Doppler ultrasonography was performed to check the pulse rate of the axillary artery, the lumen diameter, peak systolic velocity (PSV), and resistance index of the axillary artery and femoral artery on the left side, the lumen diameter, cross-sectional area, and average blood flow velocity of the axillary vein and femoral vein, and the mitral valve E peak, mitral valve A peak, tricuspid valve E peak, aortic valve PSV, and pulmonary valve PSV of the heart; an optical chromatographic skin detector was used to detect the red color, red pigment, and surface brightness of the scar on the back of the hand to reflect the filling and distribution of the scar microvessels. Data were statistically analyzed with paired sample t test. Results:Compared with those before pressure treatment, the PSV of the axillary artery of patients was significantly slowed down at 1 h of pressure treatment ( t=55.42, P<0.01); the average blood flow velocity of the axillary vein was significantly accelerated ( t=-60.50, P<0.01); the pulse rate, lumen diameter, and resistance index of the axillary artery, as well as the lumen diameter and cross-sectional area of the axillary vein did not change obviously ( P>0.05); the average blood flow velocity of the femoral vein was significantly accelerated ( t=-80.52, P<0.01); the lumen diameter, PSV, and resistance index of the femoral artery, as well as the lumen diameter and cross-sectional area of the femoral vein had no significant change ( P>0.05); the mitral valve E peak and mitral valve A peak of the heart decreased significantly (with t values of 10.71 and 21.96, respectively, P<0.01); the tricuspid valve E peak of the heart increased significantly ( t=7.57, P<0.01); the PSV of the aortic valve and pulmonary valve of the heart did not change obviously ( P>0.05). At 1 h of pressure treatment, the red color and red pigment values of the scar on the back of the hand of patients were 15.3±1.1 and 16.8±1.2, respectively, which were significantly lower than 24.5±1.3 and 23.8±1.2 before pressure treatment (with t values of 8.32 and 8.04, respectively, P<0.01). The brightness value of the scar surface on the back of the hand of patients at 1 h of pressure treatment was similar to that before pressure treatment ( P>0.05). Conclusions:After pressure treatment for the hypertrophic scar in patients secondary to extensive burn, the average blood flow velocity of the axillary vein and femoral vein in patients are obviously accelerated, the PSV of the axillary artery is significantly slowed down, the peak values of mitral valve E and mitral valve A of the heart are significantly decreased, and the tricuspid valve E peak is significantly increased. These hemodynamic changes may be related to the reduction of microvascular blood flow in the local area of scar after systemic pressure treatment.

The medicinal and edible Polygonatum cyrtonema is one of the original species of Polygonati Rhizoma. In this study,HPLC fingerprints for 25 batches of P. cyrtonema from 6 provinces were established. A total of 14 common peaks were identified and the similarities of the fingerprints were in the range of 0. 939-0. 999. In additon, the partial least squares-discriminant analysis(PLSDA) demonstrated that the samples had low discriminability except for JX-1 and most components of them had no significant correlation with environmental factors such as longitude, latitude, and altitude. Thus, chemical composition specificity of P. cyrtonema in natural distribution areas had no obvious regularity and their variation might be induced by the local environment. This conclusion explained the lack of records about Dao-di area of Polygonati Rhizoma. However, JX-1 boasted significantly higher content of 5-hydroxymethylfurfural(HMF) and 4',5,7-trihydroxy-6,8-dimethylhomoisoflavone( HIF), thick and long inflorescence and rhizome, and extremely high yield. Therefore, excellent variety of P. cyrtonema might have great potential to improve the quality and yield of Polygonati Rhizoma. Moreover, three components of HMF, polygonalline A(PA), and HIF were identified in the fingerprint. Among them, HMF has the activities of blood rheology improvement, antioxidation, and anti-myocardial ischemia and PA is an indolizine alkaloid with potential anti-inflammatory activity. HIF, the characteristic homoisoflavone in Polygonatum, has the pharmacological activities of regulating blood glucose and anti-tumor. A quantitative analysis method can provide a theoretical basis for the improvement of the quality evaluation of Polygonati Rhizoma.
Antioxidants ; Chromatography, High Pressure Liquid ; Polygonatum ; Rhizome

Objective: To learn the genotypic drug resistance of men who have sex with men ( MSM ) with HIV who failed in antiviral therapy in Yunnan Province, in order to provide basis for improving the effect of antiviral therapy. Methods: The patients who were infected with HIV-1, homosexual transmitted and failed in antiviral therapy in Yunnan Province from 2014 to 2019 were recruited. Their plasma samples were tested by reverse transcription nested polymerase chain reaction ( RT-nPCR ) , the fragments were spliced using ContigExpress, and the resistance to 8 protease inhibitors ( PIs ) , 7 nucleoside reverse transcriptase inhibitors ( NRTIs ) and 5 non-nucleoside reverse transcriptase inhibitors ( NNRTIs ) were obtained from the HIV drug resistance data website of Stanford University. Results: A total of 205 HIV/AIDS cases were included, 169 positive plasma samples were amplified, 112 cases were drug resistant, and the rate of drug resistance was 66.27%. The patients who were aged 30-49 years ( 76.09% ) , had genotype of CRF01_AE ( 76.34% ) or treated by AZT+3TC+NVP ( 77.08% ) had higher resistance rate. The resistance rates of NNRTIs, NRTIs and PIs were 62.72%, 49.70% and 2.96%, respectively; the resistance rates of NVP and EFV in NNRTIs were 62.72% and 61.54%. The main mutation site associated with NNRTIs was K103, accounting for 21.89% ( 37 cases ) ; the main mutation site associated with NRTIs was M184, accounting for 39.64% ( 67 cases ) ; the main mutation sites associated with PIs were M46L/K, accounting for 2.96% ( 5 cases ) , resulting in high resistance to NFV. Conclusions The drug resistance rate of HIV-infected MSM with failure of antiviral therapy in Yunnan Province is relatively high, with CRF01_AE as the main gene subtype of drug resistance. The drug resistance rate of NNRTIs is relatively high, especially NVP and EFV.

Objective To explore the correlation and significance of V312F locus polymorphism of PCSK9 gene in patients with coronary heart disease.Methods We selected 3560 patients with coronary heart disease who came to our hospital from January 2014 to January 2016 as the case group.They were divided into 5 subgroups:angina group,myocardial infarction group,silent myocardial ischemia group,ischemic cardiomyopathy group,and sudden death group,according to their anatomic and pathophysiological features.Data of 1 000 people for physical examination served as the control group.PCR assay combined with direct sequencing method was applied to test V312F locus polymorphism of PCSK9 gene.Logistic regression analysis was used to analyze relationship between V312F locus polymorphism of PCSK9 gene and types of coronary heart disease.The concentration of serum PCSK9 and lipids of the two groups were also measured.Results The serum levels of PCSK9,TC,TG and LDLC and ratio of positive family history in the case group were significantly higher than those in the control group,while the level of HDLC was lower than that of the controls (all P＜0.05).Indexes of sudden death subgroup in the case group showed the most significant changes,while asymptomatic myocardial ischemia subgroup showed the weakest changes.The frequency of genotype TT,GT and allele T in the case group was 3.4％,16.6％ and 11.7％,respectively,which was significantly higher than that in the control group (1.1％,10.2％ and 6.2％) (all P＜0.01).The highest frequency of genotype TT,GT and allele T was found in sudden death subgroup,and the lowest frequency of these indexes was found in asymptomatic myocardial ischemia subgroup (P＜0.05).Results of Logistic regression analysis showed that genotype TT in V312F locus of PCSK9 gene was related to the severity of coronary heart disease (OR =8.463,95％ CI from 3.505 to 17.854,P＜0.001).Conclusion The mutation of V312F (T/G)locus of PCSK9 gene might be related to the severity of coronary heart disease.