BACKGROUND:With the innovation of examination technique,the number of patients with spinal metastases in different stages is increasing year by year.Percutaneous vertebroplasty is an important treatment for spinal metastases;however,there is no report on the biomechanical effect in different stages and different activities after operation. OBJECTIVE:To simulate thoracic T10 bone stress and displacement of the different locations of the tumor metastasis based on the three-dimensional finite element model. METHODS:According to thoracic three-dimensional CT images of a 30-year-old healthy male,Mimics software was used to construct a three-dimensional geometric model of thoracic vertebrae(T9-T11),including ribs,ligaments and intervertebral discs.Three-dimensional models of T9-T11 vertebral bodies and different parts of the posterior thoracic vertebrae invaded by thoracic metastatic tumors were simulated,including the control group with intact vertebral structure,unilateral metastasis involving the vertebral body area(experimental group 1),unilateral metastasis involving the vertebral body and pedicle area(experimental group 2),unilateral metastasis involving the vertebral body,pedicle and transverse process area(experimental group 3),and bilateral metastasis involving the vertebral body,pedicle and transverse process area(experimental group 4).Abaqus software was used to create a three-dimensional finite element model.The von Mises stress distribution and the displacement of the model were analyzed under the loading condition,buckling condition,extension condition,and rotation condition. RESULTS AND CONCLUSION:(1)In the study of the maximum total displacement of loading points in different experimental groups under loading,flexion,extension,and rotation conditions,with the increase of metastatic tumor invasion site and invasion surface,the total displacement of loading points increased,and the overall stiffness decreased,especially the total displacement of loading points in experimental group 4 was the largest.(2)Under flexion condition,the maximum Von Mises stress value increased significantly after vertebral body and pedicle destruction,while the maximum Von Mises stress value was almost unchanged when the thoracocostal joint destruction was added.(3)On the basis of finite element analysis and simulation of bone tumor model,the elements in the bone cement region were set as a single set,and the bone cement region was set as the corresponding material properties to simulate bone cement filling.The results showed that the maximum total displacement under loading,flexion,extension,and rotation conditions was less than that of each experimental group.(4)The maximum stress values of the simulated percutaneous vertebroplasty patients in the loading,flexion,extension and rotation conditions were significantly lower than those of the femoral model.(5)It is concluded that the three-dimensional finite element model based on thoracic T9-T11 conducive to the biomechanics characteristics of thoracic vertebrae tumor metastasis,and on the basis of the thoracic vertebrae tumor metastasis model can accurately simulate load point after percutaneous vertebral body under different conditions of total displacement and the maximum Von Mises stress situation.

The COVID-19 epidemic has spread to the whole world for three years and has had a serious impact on human life, health and economic activities. China's epidemic prevention and control has gone through the following stages: emergency unconventional stage, emergency normalization stage, and the transitional stage from the emergency normalization to the "Category B infectious disease treated as Category B" normalization, and achieved a major and decisive victory. The designated hospitals for prevention and control of COVID-19 epidemic in Tianjin has successfully completed its tasks in all stages of epidemic prevention and control, and has accumulated valuable experience. This article summarizes the experience of constructing a hospital infection prevention and control system during the "Category B infectious disease treated as Category A" period in designated hospital. The experience is summarized as the "Cluster" hospital infection prevention and control system, namely "three rings" outside, middle and inside, "three districts" of green, orange and red, "three things" before, during and after the event, "two-day pre-purification" and "two-director system", and "one zone" management. In emergency situations, we adopt a simplified version of the cluster hospital infection prevention and control system. In emergency situations, a simplified version of the "Cluster" hospital infection prevention and control system can be adopted. This system has the following characteristics: firstly, the system emphasizes the characteristics of "cluster" and the overall management of key measures to avoid any shortcomings. The second, it emphasizes the transformation of infection control concepts to maximize the safety of medical services through infection control. The third, it emphasizes the optimization of the process. The prevention and control measures should be comprehensive and focused, while also preventing excessive use. The measures emphasize the use of the least resources to achieve the best infection control effect. The fourth, it emphasizes the quality control work of infection control, pays attention to the importance of the process, and advocates the concept of "system slimming, process fattening". Fifthly, it emphasizes that the future development depends on artificial intelligence, in order to improve the quality and efficiency of prevention and control to the greatest extent. Sixth, hospitals need to strengthen continuous training and retraining. We utilize diverse training methods, including artificial intelligence, to ensure that infection control policies and procedures are simple. We have established an evaluation and feedback mechanism to ensure that medical personnel are in an emergency state at all times.

Objective:To analyze the broadband ultrasound attenuation (BUA), speed of sound (SOS), standard deviation of bone density (T-Score) and stiffness index (SI) with bone mineral density (BMD) in elderly female patients with knee osteoarthritis and their diagnostic efficacy of osteoporosis.Methods:Fifty elderly female patients with knee osteoarthritis admitted o Tangshan People′s Hospital from January 2021 to January 2022 were selected as the observation group, and 40 healthy female patients during the same period were selected as the control group. The results of BUA, SI, T-score and SOS in observation group and control group were analyzed and compared. The BUA, SI, T-score and SOS in elderly women with knee osteoarthritis at different ages and with different bone densities were compared, and the diagnostic value of BUA, SI, T-score and SOS in osteoporosis was analyzed by receiver operating characteristic (ROC) curve.Results:The BUA, SI and T-score of observation group were lower than that in the control group, while SOS was higher than that in the control group (all P<0.05). Among elderly female patients with knee osteoarthritis of different ages, the older the age, the lower the BUA, SI and T-score (all P<0.05), while there was no statistical significance in SOS of elderly female patients with knee osteoarthritis of different ages ( P>0.05). In elderly women with knee osteoarthritis with different BMD grades, the BUA, SI, and T-score in the osteoporosis group were lower than those in the osteopenia group and the normal bone group, and the BUA, SI, and T-score in the osteopenia group were lower than those in the normal bone group; the SOS in the osteoporosis group was higher than those in the osteopenia group and the normal bone group, and the SOS in the osteopenia group was higher than those in the normal bone group (all P<0.05). BUA, SOS, T-score and SI had high sensitivity and specificity in the diagnosis of osteoporosis in elderly women with knee osteoarthritis (all P<0.05). Conclusions:BMD in elderly women with knee osteoarthritis is associated with BUA, SI, T-score, and SOS, and has high diagnostic value for osteoporosis.

Objective:To investigate the effects of placenta previa on the surgical and pregnancy outcomes in patients with total/subtotal or segmental hysterectomy attributed to placenta accreta spectrum disorders (PAS).Methods:This study retrospectively enrolled 510 patients who gave birth and underwent total/subtotal hysterectomy or segmental hysterectomy (local implantation site) due to PAS at the third Affiliated Hospital of Guangzhou Medical University from January 1, 2017, to December 31, 2022. These subjects were divided into the placenta previa group (427 cases) and non-placenta previa group (83 cases). According to the type of hysterectomy, they were further divided into the total/subtotal hysterectomy and placenta previa subgroup (221 cases), total/subtotal hysterectomy and non-placenta previa subgroup (23 cases), segmental hysterectomy and placenta previa subgroup (206 cases), and segmental hysterectomy and non-placenta previa subgroup (60 cases). Nonparametric test or Chi-square test were used to compare the differences in the clinical features, surgical and pregnancy outcomes between different groups. Binary logistic regression was used to analyze the effects of placenta previa on the risk of additional surgical procedures and adverse maternal outcomes. Results:(1) Compared with the non-placenta previa group, the hemorrhage volume within 24 h postpartum [1 541 ml (1 036-2 368 ml) vs 1 111 ml (695-2 000 ml), Z=－3.91] and the proportion of women requiring additional surgical procedures [84.8% (362/427) vs 69.9% (58/83), χ2=10.61], with total/subtotal hysterectomy [51.8% (221/427) vs 27.7% (23/83), χ2=16.10], cystoscopy and/or ureteral stenting [60.7% (259/427) vs 31.3% (26/83), χ2=24.25], total adverse pregnancy outcomes [86.9% (371/427) vs 65.1% (54/83), χ2=17.75], hemorrhage volume>1 500 ml within 24 h postpartum [54.1% (231/427) vs 33.7% (28/83), χ2=29.94], transfusion of blood products [75.9% (324/427) vs 47.0% (39/83), χ2=28.27] were all higher in the placenta previa group (all P<0.05). Binary logistic regression analysis found that for PAS patients with hysterectomy, regardless of the hysterectomy type (total/subtotal/segmental), placenta previa was risk factor for requiring additional surgical procedures ( aOR=3.26, 95% CI: 1.85-5.72) and adverse pregnancy outcomes ( aOR=5.59, 95% CI: 2.01-6.42), even if adjusting for the confounding factors such as maternal age, number of previous cesarean sections, parity, gestational weight gain, twin pregnancy, and the use of assisted reproductive technology. (2) In patients with total/subtotal hysterectomy, the proportion of women requiring additional surgical procedures was higher in those with placenta previa [82.8% (183/221) vs 56.5% (13/23), χ2=9.11] than those without placenta previa, especially the proportion of cystoscopy and/or ureteral stenting [67.9% (150/221) vs 34.8% (8/23), χ2=9.99] (both P<0.05). However, no significant difference was found in adverse pregnancy outcomes [89.6% (198/221) vs 87.0% (20/23), χ2<0.01, P=0.972] between the two groups. In patients with segmental hysterectomy, higher proportions of women requiring additional surgery [86.9% (179/206) vs 75.0% (45/60), χ2=4.94], with adverse pregnancy outcomes [84.0% (173/206) vs 56.7% (34/60), χ2=25.31], cystoscopy and/or ureteral stenting [52.9% (109/206) vs 30.0% (18/60), χ2=9.78], vascular occlusion [94.2% (194/206) vs 71.7% (43/60), χ2=24.23], hemorrhage volume>1 500 ml within 24 h postpartum [46.6% (96/206) vs 23.3% (14/60), χ2=10.37], and transfusion of blood products [68.9% (142/206) vs 33.3% (20/60), χ2=24.73] were found in the placenta previa group (all P<0.05). Furthermore, patients with placenta previa had more hemorrhage volume within 24 h postpartum [1 368 ml (970-2 026 ml) vs 995 ml (654-1 352 ml), Z=－3.66, P<0.001] in the segmental hysterectomy subgroup. After adjusting for the confounding factors such as age, number of previous cesarean sections, parity, gestational weight gain, twin pregnancy, and the use of assisted reproductive technology, binary logistic regression analysis found that placenta previa did not increase the risk of additional surgical operations ( aOR=2.71, 95% CI: 0.99-7.42) and adverse pregnancy outcomes ( aOR=2.14, 95% CI: 0.54-8.42) in patients with total/subtotal hysterectomy but were risk factors of the two outcomes for those with segmental hysterectomy ( aOR=4.67, 95% CI: 2.15-10.10; aOR=3.80, 95% CI: 1.86-7.77). Conclusions:Placenta previa increases the risk of additional surgical procedures and adverse pregnancy outcomes in patients with total/subtotal or segmental hysterectomy caused by PAS. Appropriate preparation is required after the clinical diagnosis of PAS with placenta previa.

Objective:To investigate the effects of transepithelial photorefractive keratectomy (TransPRK) and femtosecond small incision lenticule extraction (SMILE) on corneal biomechanics measured by the Ocular Response Analyzer in the early postoperative period.Methods:A cohort study was conducted.The right eyes of 56 patients who underwent TransPRK and 52 patients who underwent SMILE in Dalian Medical University Affiliated Dalian Third People's Hospital from November 2020 to June 2021 were continuously included.The postoperative follow-up was 3 months.The central corneal thickness (CCT) and keratometry (Km) were measured 1 month and 3 months after surgery.The corneal-compensated intraocular pressure (IOPcc), corneal resistance factor (CRF), corneal hysteresis (CH), and 19 repeatable mechanical infrared signal waveform parameters measured by the Ocular Response Analyzer were recorded before the surgery, 1 month and 3 months after the surgery, respectively.The measurement indexs at different time points between two groups were compared.This study adhered to the Declaration of Helsinki and the study protocol was approved by the Ethics Committee of Dalian Medical University Affiliated Dalian Third People's Hospital (No.2019-KT-010). Written informed consent was obtained from each patient before surgery.Results:There was no significant difference in CCT, Km, and IOPcc between the two groups at 1 month and 3 months after the surgery (all at P>0.05). In both groups, CRF, CH, p1area, p2area, p1area1, p2area1, w1, w2, w11, w21, h1, h2, h11, h21, dive1, dive2 and mslew1 were decreased, while path1, path2, path11, and aplhf were increased at 1 month after the surgery compared with before surgery, showing statistically significant differences (all at P<0.05). In both groups, CRF, CH, p1area, p2area, p1area1, p2area1, w1, w2, w11, w21, h1, h2, h11, h21, dive1 decreased, while path1, path2, path11, and aplhf were increased at 3 months after the surgery in comparison with before surgery, showing statistically significant differences (all at P<0.05). In SMILE group, the dive2 were decreased at 3 months after the surgery compared with before surgery, and the difference was statistically significant ( P<0.01). At 1 month after the surgery, p1area, p2area, p1area1, p2area1, w1, w2, w11, w21, dive1 and dive2 were higher, while CH, path1, path2, and path11 were smaller in TransPRK group than in SMILE group, showing statistically significant differences between them (all at P<0.05). At 3 months after the surgery, p1area, p2area, p1area1, p2area1, w1, w2, w11, w21, h2, h21, dive1 and dive2 were higher, while path1, path2, and path11 were smaller in TransPRK group than in SMILE group, showing statistically significant differences between them (all at P<0.05). Conclusions:Corneal biomechanics are weakened after both TransPRK and SMILE.In the early postoperative period, the mechanical infrared waveform parameters measured by the Ocular Response Analyzer are better after TransPRK than after SMILE.

Objective:To investigate whether the number of previous cesarean sections affects the outcomes of patients with placental implantation disease undergoing hysterectomy.Methods:Using a retrospective cohort study design, the study samples were from the obstetric clinical database of the Third Affiliated Hospital of Guangzhou Medical University, and the study subjects were patients with placental implantation disease who underwent hysterectomy. Patients were grouped according to different previous cesarean section frequencies, and their clinical characteristics, surgical outcomes, and adverse maternal outcomes were compared in each group; The impact of previous cesarean sections on adverse outcomes in pregnant women was analyzed using multivariate logistic regression.Results:Among the 244 enrolled patients, 26 had no previous history of cesarean section (11%), 132 had a previous cesarean section once (54%), and 86 had a previous cesarean section ≥2 times (35%). There was no statistically significant difference in the usage rates of uterine artery embolization, suture hemostasis, and internal iliac artery embolization among the three groups of patients (all P>0.05). Among the adverse outcomes of pregnant and postpartum women, there was no statistically significant difference in the rates of shock, bladder injury, postpartum hemorrhage, postpartum hemorrhage >1 500 ml, admission to the intensive care unit (ICU), and transfusion of blood products among the three groups (all P>0.05). Univariate logistic regression analysis showed that the number of previous cesarean sections did not increase the risk of adverse outcomes, such as shock, postpartum hemorrhage, postpartum hemorrhage ≥1 500 ml, entry into the ICU, and transfusion of blood products. Multivariate logistic regression analysis found that the number of previous cesarean sections did not increase the risk of adverse outcomes in pregnant women. Conclusions:For patients with placental implantation disease undergoing hysterectomy, the number of previous cesarean sections may not be the main factor determining maternal outcomes. It is necessary to consider other possible influencing factors more comprehensively, including previous uterine surgery history, basic health status of pregnant women, comorbidities, and availability of medical resources.

Objective:To explore the clinical value of auto-tube voltage controlled contrast medium injection based on 3rd generation dual source CT coronary angiography.Methods:Patients with suspected coronary heart disease were prospectively enrolled from March to December, 2019 at Shandong Provincial Hospital and coronary CT angiography (CCTA) images were acquired from 220 patients, including 107 male, 113 female, aged from 34 to 82 years. Patients were divided into experimental and control groups with the random number table. In experimental group (113 patients), automatic tube voltage selection technology was used, the contrast agent dosage was set according to tube voltage. The injection time was 10 s; In control group (107 patients), tube voltage and contrast agent dosage were set according to weights. The injection time was 12 s. Images were acquired by ECG gating using the 3rd generation dual source CT (DSCT) with intravenous injection of 350 mg/L contrast medium, followed up with saline of the same dose. Interclass correlation coefficient (ICC) was used to evaluate the individual bias of raters. The rank sum test was used to evaluate the group-level differences of subjective image quality and contrast agent dosage. The t-test was used to evaluate the group-level differences of objective image quality and effective radiation dose (ED). Results:The noise of aortic root in the two groups were (27±4), (26±5) HU, respectively, with no statistical difference ( t=1.017, P=0.284). All ICC values were more than 0.5 indicating good correlation batween 2 raters. The objective image quality score was no significant differences( P>0.05). The subjective image quality scores of the two groups were 1.15±0.10 and 1.18±0.12, respectively, with no statistical difference (Z=-0.231, P=0.818). The ED value (2.2±0.6) mSv of experimental group was statistically lower than that of control group (4.6±1.8) mSv ( t=-13.107, P<0.001); the contrast dosage (35±7) ml of experimental group was statistically lower than that of control group（46±6）ml ( t=-8.699, P<0.001). Conclusions:The novel scanning protocol with auto-tube voltage based contrast agent setting is more convenient and practical with reduced radiation dose and contrast dose, while maintaining image quality.

Objective: To analyze the quantitative features of coronary plaque and evaluate its diagnostic performance for myocardial ischemic injury in patient with coronary artery disease. Methods: Retrospectively enrolled 109 patients with suspected coronary artery disease, who successively underwent coronary CT angiography(CCTA) and coronary angiography in Shandong Provincial Hospital from June 2018 to September 2019. Elevated myocardial enzyme with segmental wall motion abnormalities (SWMA) in ultrasound was defined as myocardial ischemic injury, with which the subjects were divided into two groups, with and without myocardial ischemic injury (n=75,34) respectively. CCTA images of each target vessel were quantitatively analyzed by automated plaque analysis software to obtain the following indexes: minimal lumen area(MLA), plaque length(PL), total plaque volume(TPV), total plaque burden(TPB),calcified plaque volume(CPV), calcified plaque ratio(CPR), fibrous plaque volume(FPV), fibrous plaque ratio(FPR), lipid plaque volume(LPV), lipid plaque ratio(LPR), napkin-ring sign(NRS), spotty calcification(SC), remodeling index (RI) and eccentric index (EI). Chi-square, Mann-Whitney U tests, logistic regression and area under the receiver operating characteristics were determined. Results: For the degree of coronary artery stenosis, MAS% was 85.00% (80.00%, 92.00%) and 63.00% (60.00%, 65.00%) in myocardial ischemic group and without myocardial ischemic injury group, which was statistically significant (Z=-4.32, P=0.001). For the quantitative plaque features, TPV 150.13 (104.44,202.20) mm³, TPB (75.67%±9.90%), FPV 95.73 (66.57, 134.23)mm³, LPV 32.18 (18.93,54.55) mm³, LPR (25.13%±13.71%) in the group with myocardial ischemic injury were larger than those in group without myocardial ischemic injury 109.94 (79.39, 121.67) mm³, 65.37%±6.94%, 67.35 (57.67, 90.11) mm³, 16.64 (13.26, 24.73) mm³, 18.44%±7.09% respectively with statistically significant (Z=-2.59, P=0.010; t=3.11, P=0.003; Z=-2.16, P=0.031; Z=-2.18, P=0.029; t=2.19, P=0.037). In logistic regression analysis, MAS%(OR=1.55,P=0.021) was independent significant predictors of myocardial ischemic injury. The AUC of MAS%, LPV, LPR, TPV, TPB, FPV were 0.84, 0.82, 0.77, 0.72, 0.74, 0.67, respectively, which were all statistically significant (P<0.05). Conclusions In quantitative plaque analysis by coronary CT angiography, MAS%, TPV, TPB, FPV, LPV, LPR were affecting factors of myocardial ischemic injury, in which MAS% was independent predictors. MAS% and LPV have higher diagnostic accuracy in myocardial ischemic injury.

The purpose of the present work is to establish an ultra-minimal invasive percutaneous puncture inoculation method for a VX2 orthotopic lung cancer rabbit model with fewer technical difficulties, lower mortality of rabbits, a higher success rate and a shorter operation time, to evaluate the growth, metastasis and apoptosis of tumor by CT scans, necropsy, histological examination, flow cytometry and immunohistochemistry. The average inoculation time was 10–15 min per rabbit. The tumor-bearing rate was 100%. More than 90% of the tumor-bearing rabbits showed local solitary tumor with 2–10 mm diameters after two weeks post-inoculation, and the rate of chest seeding was only 8.3% (2/24). The tumors diameters increased to 4–16 mm, and irregularly short thorns were observed 3 weeks after inoculation. Five weeks post-inoculation, the liquefaction necrosis and a cavity developed, and the size of tumor grew further. Before natural death, the CT images showed that the tumors spread to the chest. The flow cytometry and immunohistochemistry indicated that there was less apoptosis in VX2 orthotopic lung cancer rabbit model compared to chemotherapy drug treatment group. Minimal invasive percutaneous puncture inoculation is an easy, fast and accurate method to establish the VX2 orthotopic lung cancer rabbit model, an ideal in situ tumor model similar to human malignant tumor growth.
Apoptosis ; Drug Therapy ; Flow Cytometry ; Humans ; Immunohistochemistry ; Lung Neoplasms* ; Lung* ; Methods* ; Mortality ; Necrosis ; Neoplasm Metastasis ; Punctures* ; Rabbits ; Thorax ; Tomography, X-Ray Computed

BACKGROUND: Based on a mouse model of tibial implantation, some scholars have found that the CaP-coated implant with recombinant human parathyroid hormone (1-34) (PTH(1-34)) shows strong osteogenesis effect at early stage, but this coating has not been applied in the oral environment.OBJECTIVE: To explore the role of local application of PTH(1-34) on immediate implant osseointegration . METHODS: Nine New Zealand white rabbits were randomly divided into two groups (six in experimental group and three in control group). All of the tooth sockets were filled with heterogeneous freeze-dried bone firstly after four incisors of each rabbit were extracted. In the experimental group, a titanium screw with PTH(1-34) loaded CaP coating was implanted into each tooth socket, while in the control group, a titanium screw with only CaP coating was implanted. The animals were executed respectively at 4, 8, 12 weeks after operation, and the intact maxillary and mandibular specimens were harvested and tested by gross observation, bone density analysis, torque test, histologic al observation, X-ray observation.RESULTS AND CONCLUSION: The gray value and maximum torque value of regenerated osseous tissue at different time points in the experimental group were significantly higher than those in the control group (P < 0.05). Within 4-12 weeks after implantation, regenerated and mature bone tissue appeared earlier in the experimental group than the control group. A large amount of new blood vessels were seen in the experimental group at 8 weeks after implantation, while in the control group, there were only few new blood vessels. To conclude, the local application of PTH(1-34) can promote bone formation, improve the implant-bone bonding strength, and enhance the stability of the implant.