OBJECTIVE: To compare the biomechanical differences among the five internal fixation modes in treatment of Day type Ⅱ crescent fracture dislocation of pelvis (CFDP), and find an internal fixation mode which was the most consistent with mechanical principles. METHODS: Based on the pelvic CT data of a healthy adult male volunteer, a Day type Ⅱ CFDP finite element model was established by using Mimics 17.0, ANSYS 12.0-ICEM, Abaqus 2020, and SolidWorks 2012 softwares. After verifying the validity of the finite element model by comparing the anatomical parameters with the three-dimensional reconstruction model and the mechanical validity verification, the fracture and dislocated joint of models were fixed with S ₁ sacroiliac screw combined with 1 LC-Ⅱ screw (S ₁+LC-Ⅱ group), S ₁ sacroiliac screw combined with 2 LC-Ⅱ screws (S ₁+2LC-Ⅱ group), S ₁ sacroiliac screw combined with 2 posterior iliac screws (S ₁+2PIS group), S ₁ and S ₂ sacroiliac screws combined with 1 LC-Ⅱ screw (S ₁+S ₂+LC-Ⅱ group), S ₂-alar-iliac (S ₂AI) screw combined with 1 LC-Ⅱ screw (S ₂AI+LC-Ⅱ group), respectively. After each internal fixation model was loaded with a force of 600 N in the standing position, the maximum displacement of the crescent fracture fragments, the maximum stress of the internal fixation (the maximum stress of the screw at the ilium fracture and the maximum stress of the screw at the sacroiliac joint), sacroiliac joint displacement, and bone stress distribution around internal fixation were observed in 5 groups. RESULTS: The finite element model in this study has been verified to be effective. After loading 600 N stress, there was a certain displacement of the crescent fracture of pelvis in each internal fixation model, among which the S ₁+LC-Ⅱ group was the largest, the S ₁+2LC-Ⅱ group and the S ₁+2PIS group were the smallest. The maximum stress of the internal fixation mainly concentrated at the sacroiliac joint and the fracture line of crescent fracture. The maximum stress of the screw at the sacroiliac joint was the largest in the S ₁+LC-Ⅱ group and the smallest in the S ₂AI+LC-Ⅱ group. The maximum stress of the screw at the ilium fracture was the largest in the S ₁+2PIS group and the smallest in the S ₁+2LC-Ⅱ group. The displacement of the sacroiliac joint was the largest in the S ₁+LC-Ⅱ group and the smallest in the S ₁+S ₂+LC-Ⅱ group. In each internal fixation model, the maximum stress around the sacroiliac screws concentrated on the contact surface between the screw and the cortical bone, the maximum stress around the screws at the iliac bone concentrated on the cancellous bone of the fracture line, and the maximum stress around the S ₂AI screw concentrated on the cancellous bone on the iliac side. The maximum bone stress around the screws at the sacroiliac joint was the largest in the S ₁+LC-Ⅱ group and the smallest in the S ₂AI+LC-Ⅱ group. The maximum bone stress around the screws at the ilium was the largest in the S ₁+2PIS group and the smallest in the S ₁+LC-Ⅱ group. CONCLUSION For the treatment of Day type Ⅱ CFDP, it is recommended to choose S ₁ sacroiliac screw combined with 1 LC-Ⅱ screw for internal fixation, which can achieve a firm fixation effect without increasing the number of screws.
Adult ; Male ; Humans ; Finite Element Analysis ; Fracture Fixation, Internal/methods* ; Fractures, Bone/surgery* ; Pelvis ; Spinal Fractures/surgery* ; Fracture Dislocation/surgery* ; Joint Dislocations/surgery* ; Biomechanical Phenomena

Objective:To analyze the relationship between preoperative deep vein thrombosis (DVT) and parameters of conventional coagulation tests (CCTs) and thromboelastography (TEG) in patients with acute trauma, and to establish a prediction model to screen out high-risk patients with preoperative DVT.Methods:The clinical data of patients with acute traumatic fracture admitted to the Emergency Intensive Care Unit of Shanghai Sixth People’s Hospital from January 2021 to June 2021 were retrospectively collected. According to whether preoperative DVT occurred, the patients were divided into the DVT group and non-DVT group. The differences of CCTs and TEG parameters at the same time were compared between the two groups. Logistic regression analysis was applied to identify independent risk factors for DVT after trauma. The receiver-operating characteristic curve analysis was employed to analyze the clinical value of those parameters to predict preoperative DVT.Results:Among 123 patients with acute traumatic fracture, 101 patients were treated with anticoagulation before operation, and 51 patients were diagnosed with DVT. There were significant differences in activated partial thromboplastin time, fibrinogen (Fib), D-Dimer, fibrinogen degradation products (FDPs), reaction time, clotting time, α angle, maximum amplitude (MA) and coagulation index between the DVT and non-DVT groups. D-Dimer and MA were independent risk factors for preoperative DVT in patients with traumatic fracture. Logistic regression equation was used to establish a prediction model: the predicting index = 0.101×D-Dimer +0.241×MA + (-18.190). The α angle (AUC=0.833, P<0.001), MA (AUC=0.904, P<0.001), coagulation index (AUC=0.914, P<0.001) of TEG versus Fib (AUC=0.684, P=0.001), D-Dimer (AUC=0.685, P<0.001) and FDPs (AUC=0.656, P=0.003) of CCTs had a higher diagnostic efficacy in developing DVT of lower extremity in patients with traumatic fracture, and of all the coagulation index was the best. However, the predictor of D-Dimer combined with MA had a better predictive value (AUC=0.926, P<0.001), and the best cut-off value was 0.32 with a sensitivity and specificity of 90.2% and 79.8%, respectively. Conclusions:Compared with CCTs, TEG has more advantages in predicting preoperative DVT in patients with traumatic fracture, and the predictor of D-Dimer combined with MA can screen out patients with high risk of DVT, which can be recommended for clinical application.

Objective To investigate the relationships between serum osteocalcin (OC) levels and glycometabolism markers in nondiabetic post-traumatic male patients.Methods Populaitons were selected at the Department of Emergency Medicine of Shanghai Jiao Tong University Affiliated Sixth People's Hospital from October 2017 to February 2019.The age,injury severity score (ISS),and characteristic indicators were recorded.The inclusion criteria were age ≥ 18 years and blood collection time ＜ 24 h after the injury.The exclusion criteria were emergency surgery,acute brain trauma,and hemoglobin A1c (HbA1c) ≥ 6.0％.The patients were divided into two groups by fasting plasma glucose (FPG):stress hyperglycemia (SH) (FPG＞7.8 mmol/L) and nonstress hyperglycemia (NO-SH) (FPG ≤ 7.8 mmol/L) groups.The fasting venous blood samples were collected and examined.The characteristics and biochemical indicators in the two groups were compared statistically by LSD-t test,rank sum test and ANOVA,and the relationships between serum OC levels and glycometabolism markers were analyzed by partial correlation analysis.Results A total of 395 traumatic patients were enrolled and divided into the SH group (n=182) and NO-SH group (n=213).There were no differences in ISS,fasting insulin (FINS),and C-peptide (C-P) levels between groups.Age,HbAlc and FPG were higher (P=0.041,P=0.037,P＜0.01),while the OC level was lower (P=0.023),in the SH group than those in the NO-SH group.The serum OC level did not correlate with HbAlc,FPG,and FINS,but negatively correlated with C-P by partial correlation analysis (r=-0.262,P=0.008).The multivariate linear regression analysis showed that C-P was an independent factor affecting serum OC levels after trauma (β=-0.655,P=0.043).Conclusion A correlation existed between the serum OC level and glycometabolism markers in nondiabetic post-traumatic male patients.

Objective:To explore the clinical significance and underlying mechanism of changes in serum IL - 18 and IL - 1 beta after trauma.Methods:Enzyme-linked immunosorbent assay was used to detect the levels of IL-18 and IL-1β in trauma patients and healthy controls. The differences in serum IL-18 and IL-1β levels were compared between the two groups, and the levels of IL-18 and IL-1β in the traumatic subgroups were further compared.Results:The serum levels of IL-1β and IL-18 of trauma patients were 80±2.0 pg/mL and 27±3.0 pg/mL, respectively, which were significantly higher than those in healthy controls ( P < 0.01). Serum levels of IL-1β and IL-18 showed an upward trend on the 3rd day after trauma. There were also statistically significant differences within the trauma subgroups ( P < 0.01). Conclusions:The serum levels of IL-18 and IL-1β of post-traumatic patients are increased, indicating that NLRP3 inflammasomes are activated in peripheral blood cells in the early stage of trauma, which aggravates the inflammatory response. The AIS-ISS score is positively correlated with the expression levels of IL-18 and IL-1β in serum, indicating that the more severe the injury, the more severe the inflammatory response.

Objective: To assess the diagnosis of thrombelastography (TEG) for trauma-induced coagulopathy (TIC) and explore whether TEG could guide transfusion for TIC patients. Methods: We retrospectively analyzed all trauma patients who underwent the TEG and conventional coagulation tests (CCTs) admission in the emergency intensive care unit from February to December 2018. The definition of TIC is prothrombin time (PT) 18 s, international normalized ratio (INR) 1.5, activated partial thromboplastin time (APTT) 60 s or platelet count (PLT) 100×10⁹/L. The diagnostic value of TEG for TIC was evaluated by receiver operating characteristic curve, area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), and the transfusion guidance of TEG for TIC patients was assessed by multivariate regression analyses. Results: A total of 242 patients were included, including 62 patients in the TIC group and 180 patients in the non-TIC group. The differences in TEG between the two groups were statistically significant. The AUCs of TIC assessed by maximum amplitude (MA) and coagulation index (CI) were the largest, 0.779 and 0.786 respectively, and the sensitivity were greater than 80% and NPV were greater than 90%. The sensitivity, PPV and NPV of reaction time (R) were minimal. After confounders were controlled, all TEG values were correlated with blood volumes within the first 24 h and massive transfusion, of which R had the highest odds ratio and regression coefficient. Conclusions MA and CI have the highest diagnostic value, while R has little diagnostic value but a relatively large blood therapeutic significance of TIC. MA < 52.9 mm or CI < -1.0 can be used as a threshold for identifying TIC. The diagnosis of TIC and the guidance transfusion for TIC patients by TEG is beneficial.

Objective To compared different fixation methods for acetabular fractures involving the quadrilateral plate using a finite element model of the acetabulum.Methods A model of acetabular fractures with quadrilateral plate involved was developed in the finite element software and processed in Hypermesh V10.0 to generate internal fixation with dual-column titanium plate (Group A),anterior special titanium moulding plate plus quadrilateral screws (Group B),and anterior special titanium moulding plate plus quadrilateral screws combined with posterior column screws (Group C).Pelvic stress in sitting and standing positions were simulated in sequence with constraint of tuber nodes and inferior femur.Maximum stress and displacement of the acetabulum and displacement of nodes on fracture lines were measured after a force of 600 N was applied to S1 verterbrae in line with the direction of gravity in sitting and standing positions.Results In sitting position,the maximum stress and displacement of the acetabulum exhibited a sequence of Group C (9.47,1.08) ＜ Group B (19.84,1.11) ＜ Group A (29.73,1.14).Moreover,the same result was found in standing position with Group C (9.62,1.09) ＜ Group B (12.18,1.10) ＜ Group A (13.28,1.13).Mean displacement of nodes on fracture lines ranked in order of Group C ＜ Group B ＜ Group A (P ＞ 0.05).Conclusions The finite element model can reflect the distribution of pelvic stress effectively.Anterior special titanium moulding plate plus quadrilateral screws combined with posterior column screws provide favorable biomechanical stability in treatment of acetabular fractures involving the quadrilateral area.

The international road of Chinese medicine can be comparable to the Long March of the Red Army. The article reviews the history, global impact and achievements of the World Congress of Chinese Medicine (WCCM) on its way to the TCM's globalization in the past decade. It also discusses the great significance of WCCM's effort. The article concludes by bringing up a scheme for further developing the WCCM and envisioning its promising future.

Objective To investigate the effect of Alzheimer' s beta-amyloid (Aβ) on the production and the translocation in cytoplasm of retinoid receptor-α (RXRα). MethodsN2awt cells were treated with Aβ peptide or amyloid protein precursor(APP695) transfection. The nucleus were separated from the cytoplasm by kit. The quantity of RXRα in the nucleus and cytoplasm was detected by Westernblot. The translocation of RXRα in the nucleus and cytoplasm of above N2awt cells or of the cortex cells in the brains of Alzheimer' s disease (AD) patients and their normal control groups was observed by immune fluorescence. ResultsIn N2awt cells, the increasing APP or Aβ had no significant effect on the production of RXRα but resulted in RXRα exporting into cytoplasm, the ratio of RXRα in cytoplasm increased from 3.2％ (in control group) to 17.6％ (in APP+ group) and from 3.8％ (in control group) to 14.3％ (in Aβ + group) respectively; compared with normal cortex cells, the translocation of RXRα in the cytoplasm of the cortex cells in the brains of AD increased significantly. ConclusionAβ may affect RXRα exporting into cytoplasm.

Objective To screen the liver cell proteins interacting with the novel protein encoded by the 2.2 kb singly spliced variant of hepatitis B virus genome. Methods The splicing-specific gene TPss generated by the 2.2 kb singly spliced variant of HBV genome was amplified by PCR and cloned into the bait vector pGBKT7. After exclusion of self-activatian capacities of TPss protein, a two-hybrid library screening was performed using a pre-transformed human liver cDNA library to screen the liver cell proteins interacting with TPss. Mammalian two-hybrid assay was also done to further confirm the interactions between the bait and prey proteins in Huh7 and HepG2 hepatacytes. Results TPss gene with the size of 336 bp was successfully amplified and cloned, and the TPss protein expressed well in AHI09 yeast cells. Four liver cell proteins interacting with TPss, i. e. , cathepsin B, epoxide hydrolase 1, cathepsin D and fibrinogen gamma chain, were screened by yeast two-hybrid assay and further confirmed by mammalian two-hybrid assay. Conclusion TPss could interact with liver cell proteins.

OBJECTIVE To investigate the correlated resistant genes encoding ?-lactamases,aminoglycoside and genetic marker of integron and transposon in multi-resistant Pseudomonas aeruginosa(MRPA) isolated from clinical specimens and study their relationship by phylogenetic analysis.METHODS Twenty-one resistant genes,two integron-Ⅰ genes and one transposon genetic gene were analyzed by PCR and verified by DNA sequencing.Multi-resistant genes cluster analysis was performed by UPGMA.RESULTS The positive rates of CARB,oprD2,aac(3)-Ⅱ,aac(6′)-Ⅱ,ant(2″)-Ⅰ,intⅠ1,qacE△1-sul1 and merA in 20 strains of MRPA were 15%,100%,70%,15%,15%,85%,85% and 85%,respectively,and other genes were negative.It was classfied to three subgroup,by the multi-resistant genes cluster analysis.CONCLUSIONS MRPA isolated from clinical specimens has carried many resistant genes.The deficiency rate of oprD2 gene is very high.The positive rate of genetic mark genes about integron and transposon is very high.It may be the main multi-resistant mechanism of MRPA.Multi-resistant genes cluster analysis shows that there is clone transmission in MRPA and it can induce nosocomial infection prevalence.