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1.
Cancer Research on Prevention and Treatment ; (12): 988-993, 2023.
Article in Chinese | WPRIM | ID: wpr-997691

ABSTRACT

Objective To investigate the clinical efficacy of peripheral blood stem cell transplantation from haploidentical and matched sibling donors for treatment of high-risk and refractory/relapsed acute myeloid leukemia (AML). Methods Data on the efficacy of haploidentical peripheral blood stem cell transplantation (Haplo-HSCT) with myeloablative conditioning regimen were retrospectively analyzed and compared with that of matched sibling donors' peripheral blood stem cell transplantation (MSD-HSCT) for treatment of high-risk refractory/relapsed AML in our center from January 1st, 2010 to June 30th, 2020. Results A total of 98 patients were enrolled, including 62 patients in the Haplo-HSCT group and 36 patients in MSD-HSCT group. The median age, conditioning regimen, and infusion doses of MNC and CD34+ cells were significantly different between the two groups, but no significant differences in other baseline parameters were found. Transplantation-related infectious complications and the incidence of acute and chronic graft-versus-host disease (GVHD) were also not significantly different between the two groups. The 3-year cumulative relapse in the Haplo-HSCT group was significantly lower than that in the MSD-HSCT group (16.2% vs. 41.1%, P=0.036). The 3-year DFS of the Haplo-HSCT and MSD-HSCT groups were 66.98% and 41.8%, respectively (P=0.140), and their OS were 73.37% and 51.41%, respectively (P=0.105). Conclusion The clinical efficacy of Haplo-HSCT for the treatment of high-risk and refractory/relapsed AML is similar to that of MSD-HSCT, and Haplo-HSCT may have better GVL effect.

2.
Journal of Pharmaceutical Practice ; (6): 594-599, 2023.
Article in Chinese | WPRIM | ID: wpr-996916

ABSTRACT

Objective To prepare and optimize the formulation of Albumin nanoparticles loading PROTAC molecule and observe the inhibition effect of nanoparticles on the proliferation and NAD+ metabolism of glioma cells. Methods Albumin nanoparticles loading NPT-B2 were prepared and characterized with a thermal driving method, and the prescription was optimized. An HPLC method was established to determine the content of NPT-B2. The proliferation inhibition of NPT-B2 and B2-BSA-NPs on U251 cells were investigated by the CCK8 method, and the degradation effects of NPT-B2 and B2-BSA-NPs on NAMPT in glioma cells were investigated by western blotting. Results The HPLC method was stable, with good linearity, precision, and recovery rate. The nanoparticles had a particle size of about 55.48 nm, a potential of about −12.9 mV, an encapsulation rate of about 94.74%, and a drug loading amount of about 8.61%. The IC50 of NPT-B2 on glioma cells was 61.16 nmol/L, which had a degradation effect on NAMPT. The IC50 of B2-BSA-NPs on glioma was 41.21 nmol/L, which had a very significant degradation effect on NAMPT. Conclusion Albumin nanoparticles loading PROTAC molecules were constructed. The prescription was optimized to improve the drug encapsulation rate, and the low water solubility of PROTAC molecule was improved, which had a significant inhibitory effect on the proliferation and NAD+ energy metabolism of glioma cells.

3.
Chinese Journal of Hospital Administration ; (12): 399-403, 2023.
Article in Chinese | WPRIM | ID: wpr-996097

ABSTRACT

Objective:To analyse the settings of sub-campus of public hospitals directly under the National Health Commission, so as to provide research reference and suggestions for further promoting the scientific and standardized construction of sub-campuses of public hospitals.Methods:Data before August 30, 2022 were collected from the official websites of the hospitals in question including their introduction, overview, navigation, news and other categories of information.Relevant literatures on multi-campus published by hospitals under the direct management of the National Health Commission were obtained from the China National Knowledge Network, which was identified by searching the keywords " sub or multi-campus hospital" with " author affiliation", using such search conditions as " MeSH major topic" or " title/keywords/abstract" of the studied hospitals in advanced search builder. Descriptive analysis and frequency analysis were conducted on the numbers, the construction reasons, geographical location, operation scale, characteristics and positioning of the sub-campuses in the studied hospitals.Results:Of the 44 such hospitals, 30 had a total of 50 sub-campuses in operation. Generally there were two modes of construction. 35 were newly constructed and 15 formed by mergers; 37 sub-campuses were built and put into operation since 2010. Sub-campuses were usually located in the same area of the main campus, with 11 in the same area of the same city and areas, 35 in different areas of the same city, and 4 in different cities; the average geographical distance between the sub-campus and the main hospital campus was 31.18 kilometers; 27 sub-campuses had beds ≤ 500, 12 sub-campuses had beds between 501-1 000, 11 had beds>1 000; 14 specialized sub-campuses and 31 out of the 35 comprehensive sub-campuses clearly indicating their characteristics of specialized departments, and 1 other (research institute areas with research beds).Conclusions:Future proofing is characteristic of these public hospitals in terms of their sub-campus construction, regional setting, planning and positioning, and functional layout. However, both government regulatory departments and public hospitals should comprehensively consider and make prudent decisions on the planning, investment, demonstration, layout, and other aspects of the construction of sub-campuses of hospitals.

4.
Journal of Pharmaceutical Practice ; (6): 265-272, 2023.
Article in Chinese | WPRIM | ID: wpr-973682

ABSTRACT

As a type of extracellular vesicles, exosomes are released by living cells and contain diverse bioactive molecules, including nucleic acids, proteins, lipids and metabolites. They play an important role in various physiological and pathological processes by a special intercellular communication medium. As endogenous vesicles, exosomes also have the advantages of systemic circulation stability, good biocompatibility and specific targeting of tissues and cells, as well as they are promising candidates for drug delivery system. The production mechanism of exosomes describe was summarized, the methods of extraction and separation the application and mechanism of exosomes in immune and inflammation-related diseases, cardiovascular system diseases, nervous system diseases, tumors, etc. were reviewed. The engineering modifications of exosomes in high targeting properties based on the drug delivery were overviewed. Exosomes support the diagnosis and prognostic assessment of multiple diseases, which have broad application prospects as a very potential safe and specific endogenous nano-drug carrier.

5.
Journal of Pharmaceutical Practice ; (6): 26-30, 2023.
Article in Chinese | WPRIM | ID: wpr-953754

ABSTRACT

Objective To prepare a biomimetic nano carrier macrophage membrane hybrid liposome by heterozygous macrophage membrane and liposome, which could be used for the clearance and toxicity inhibition of Vibrio vulnificus hemolysin A (VvhA). Methods Macrophage membrane was extracted and hybridized with liposome by thin-film evaporation combined extrusion method. The hybridized liposome of macrophage membrane was constructed and characterized. The in vitro detoxification ability of the hybridized vector was evaluated by hemolysis test and cytotoxicity test. The detoxification ability of the vector was evaluated by mouse skin infection model. Results Anti toxoid studies in vivo and in vitro showed that the anti-hemolysis rate of macrophage membrane heterozygous liposomes in vitro reached 97.03%, which could effectively inhibit the skin ulceration in subcutaneous infected mice and make the survival rate of abdominal infected mice reach 80%. Conclusion The constructed macrophage membrane hybrid liposome had high detoxification ability, which could provide a potential solution and research basis for the prevention and treatment of Vibrio vulnificus infection.

6.
Chinese Journal of Endocrine Surgery ; (6): 253-255, 2023.
Article in Chinese | WPRIM | ID: wpr-989936

ABSTRACT

Thyroid cancer is the most common malignant tumor of the endocrine system, and its incidence is increasing year by year showing younger trend. The pathological types of thyroid cancer are papillary carcinoma, follicular carcinoma, medullary carcinoma and undifferentiated carcinoma. Medullary thyroid carcinoma (MTC) and papillary thyroid carcinoma (PTC) are the two common types of thyroid cancer. Since MTC and PTC have different biological origins, invasiveness and prognosis. Therefore, the occurrence of both medullary carcinoma and papillary carcinoma is very rare and rarely reported in China and abroad and the treatment is challenging. In this paper, we review the pathogenesis, ancillary tests, diagnosis and treatment of this disease, with the aim of providing reference for clinical treatment of patients with medullary thyroid carcinoma complicated by papillary carcinoma.

7.
Chinese Journal of Endocrine Surgery ; (6): 120-123, 2023.
Article in Chinese | WPRIM | ID: wpr-989908

ABSTRACT

In recent years, clinical applications of robotic thyroid surgery have been gradually promoted with the continuous improvement of the da Vinci robotic surgical system. Unlike traditional open surgery, robotic thyroid surgery mainly adopts remote access, which has many advantages, such as magnified high-definition 3D view and hand vibration stabilization. The rates and causes of postoperative complications differ due to different approaches, view angles, and operation sequences. This paper presents the literature on both transoral and bilateral areolar axillary approaches in robotic thyroid surgery, focusing on five common complications under both approaches, including laryngeal recurrent nerve injury and hypoparathyroidism, to provide theoretical support for the standardization of robotic thyroid surgery.

8.
Journal of Pharmaceutical Practice ; (6): 135-138, 2023.
Article in Chinese | WPRIM | ID: wpr-965561

ABSTRACT

Nanocarriers prepared from organic or inorganic materials are widely used in drug targeting system and diagnosis and treatment of disease. However, there are some problems, such as poor targeting, short circulation time in vivo and improvement in the biocompatibility. Biomimetic nanocarriers has carried out research on the issues, which based on different kinds of cell membrane for the nanocarriers modification, endogenous biofilm improving the biocompatibility of carriers in vivo, more accurate targeting, and even producing immunotherapeutic effect. The principle, method, targeting mechanism and therapeutic effect of biomimetic nano carrier technology of cell membrane have been reviewed in this paper, which provide a new direction for the research of new drug delivery system.

9.
Chinese Journal of Hospital Administration ; (12): 143-146, 2022.
Article in Chinese | WPRIM | ID: wpr-934580

ABSTRACT

Objective:To analyze the characteristics of the circular cases violating the " nine prohibitions" in recent years, so as to provide a basis for further strengthening the moral culture construction of the healthcare industry.Methods:Data came from the reported cases released on official websites of the discipline inspection committees, supervision committees and health committees at all levels in China from December 2013 to August 2021, which were identified by searching the keyword " case or report or moral culture and nine prohibitions" . Descriptive analysis and frequency analysis were conducted on the reported time, region and province, as well as the involved units, departments, persons, punishment results and case classification data of all the cases.Results:A total of 102 cases violating the " nine prohibitions" were included, of which the cases from 2014 to 2015 topped the rest, accounting for 51.96%(53 cases). Top three regions of these cases were central China, east China and southwest China, with 31 cases, 27 cases and 18 cases respectively. The units involved were mainly tertiary medical institutions, accounting for 44.12%(45 cases). More medical staff(134 people) than administrative staff(85 people) were involved in the cases. The largest number of cases was receiving kickbacks, with 52 cases(50.98%). The punishment results of cases included judicial procedures(76 people), Party discipline and government discipline punishment(67 people) and organizational punishment(76 people).Conclusions:Moral culture problem in China′s healthcare sector is characterized in wide coverage, complexity, comprehensiveness and long-term. Relevant authorities should keep up their efforts in enhancing the awareness of medical workers, improving the synergy mechanism in this regard, and strengthening the internal management of medical institutions.

10.
Chinese Journal of Organ Transplantation ; (12): 298-302, 2022.
Article in Chinese | WPRIM | ID: wpr-933690

ABSTRACT

Objective:To explore the safety of inactivating coronavirus disease 2019(covid-19)vaccine in liver transplantation(LT)recipients.Methods:Retrospective analysis was performed for clinical data of 151 LT recipients from March 2003 to October 2019.They had stable conditions and completed the course of covid-19 vaccine.Frequencies of pain at injection site, fatigue, headache and pruritus after vaccination were recorded.The safety profiles were compared between recipients with and without local and general adverse reactions after vaccination.At the same time, recipients completing two doses of covid-19 vaccines were grouped.According to vaccine companies, they were classified into Sinovac Biotech Ltd and Beijing Biological.Based upon more than or less than 60 years, they were grouped into <60 years and ≥60 years.The safety profiles of inactivating COVID-19 vaccine were compared in subgroups.Results:Among 151 eligible LT recipients, 98 of them were in group of age <60 years and 53 in group of age >60 years.The median period between vaccination and LT was 8.44(4.37, 12.39)years and the median concentration of tacrolimus 2.5(1.8, 3.9)ng/L.Eighty-three cases completed two doses of Sinovac Biotech Ltd(Sinovac Biotech Ltd group)and 40 cases Beijing Biological(Beijing Biological group); 14 cases had combined course of Sinovac Biotech Ltd and Beijing Biological, four recipients were vaccinated with inactivated vaccine from other companies and ten recipients did not know their inactivated vaccine' companies.After immunization, 24/151(15.9%)recipients had a local and general adverse reaction.The prevalence of pain at injection site, fatigue, headache and pruritus was 9.9%( n=15), 5.2%( n=8), 1.3%( n=2)and 0.7%( n=1)respectively.No significant differences existed in age( P=0.602), gender( P=0.752), period after LT( P=0.890), trough concentration of tacrolimus( P=0.377)or versions of covid-19 vaccine( P=0.582)between 24 cases with general adverse reaction and 127 without.Local and general reactions occurred in 16/83(19.3%)in Sinovac group and 5/40(12.5%)in Beijing Biological.There was no significant inter-group difference( P=0.769). There were 98 cases(64.9%)in <60 years group, 17 cases(17.3%)had local and general reaction, 53 cases(35.1%)in ≥60 years group and 7 cases(13.2%)had a local and systemic reaction.There was no significant inter-group difference( P=0.507). Conclusions:Covid-19 vaccine is safe for long-term survival LT recipients with normal liver function.Few participants present with mild fatigue and pain at injection site.

11.
Chinese Journal of Hospital Administration ; (12): 180-183, 2022.
Article in Chinese | WPRIM | ID: wpr-958754

ABSTRACT

Because the work of administrative and logistics personnel in public hospitals is difficult to quantify and evaluate, its performance reform is difficult. A large public hospital in Wuhan has explored and established a distribution incentive mechanism that combines department performance appraisal, individual classification and grading, and secondary distribution within the department. Taking into account the completion of performance appraisal indicators of the national tertiary public hospital in the department, the results of the institutional " Excellent Management Team Ranking" , personal job grades, working years and other factors, a relatively mature and operable system has been formed, which could provide reference for the performance reform of other hospitals.

12.
Chinese Journal of Hepatobiliary Surgery ; (12): 735-739, 2022.
Article in Chinese | WPRIM | ID: wpr-957035

ABSTRACT

Objective:To study the risk factors and treatment of portal vein thrombosis (PVT) in patients after liver transplantation.Methods:The clinical data of 290 recipients who underwent liver transplantation at the Department of Hepatology, the Fifth Medical Center of PLA General Hospital from July 2015 to April 2019 were retrospectively analyzed. There were 245 males and 45 females, with a median age of 51(44, 56) years old. The liver transplantation recipients were divided into two groups according to whether PVT occurred or not after operation: the PVT group ( n=16) and the non-PVT group ( n=274). Gender, age and other clinical data of the recipients were compared between the two groups. Outpatient and inpatient follow-up were performed. The risk factors of postoperative PVT were analysed in the liver transplantation recipients. Results:The median follow-up of these 290 liver transplant recipients was 59(42, 73) months, and 16 patients were confirmed to have PVT after operation, with an incidence of 5.5%(16/290). Multivariate logistic regression analysis showed that preoperative PVT ( OR=12.773, 95% CI: 3.887-41.973) was an independent risk factor for PVT after liver transplantation. For the 16 patients with postoperative PVT, 10 were treated with portal vein intervention, and the remaining 6 patients were treated with oral aspirin or rivaroxaban anticoagulation due to mild symptoms. The 3-year survival rate of the PVT group was 93.8% (15/16), while that of the non-PVT group was 90.1% (247/274). There was no significant difference in the 3-year survival rates between the two groups (χ 2<0.01, P=0.969). Conclusions:Preoperative PVT in recipients was an independent risk factor for PVT after liver transplantation. For patients with postoperative PVT, appropriate treatment resulted in good results without affecting the long-term prognosis of these patients.

13.
Chinese Journal of Hepatobiliary Surgery ; (12): 425-429, 2022.
Article in Chinese | WPRIM | ID: wpr-956977

ABSTRACT

Objective:To study the impact of simultaneous ligation of splenic artery on prognosis of patients with severe hypersplenism in liver transplantation.Methods:A retrospective analysis was performed on the clinical data of 206 patients who underwent liver transplantation in the Fifth Medical Center of PLA General Hospital from December 2016 to February 2019. There were 180 males and 26 females, aged (51.0±9.0) years old. Fifty-one patients underwent splenic artery ligation during liver transplantation and they were enrolled into the observation group, and 155 patients without splenic artery ligation were enrolled into the control group. The changes in white blood cells (WBC), platelets, alanine aminotransferase, total bilirubin and serum creatinine as well as the incidence of postoperative complications were compared between the two groups.Results:The platelet count of the observation group was significantly lower than those of the control group before operation and on days 1, 3, 7, 30 and 90 after operation, (all P<0.05). The WBC counts in the observation group were significantly lower than those in the control group before operation and on days 1 and 3 after operation (all P<0.05). However, there were no significant differences in the WBC counts between the two groups on days 5, 7, 30 and 90 after operation (all P>0.05). There were also no significant differences in alanine aminotransferase and total bilirubin indexes between the two groups after surgery (all P>0.05), but the serum creatinine levels in the observation group were significantly lower than those in the control group on days 3, 5, 7 and 30 after surgery (all P<0.05). There were no significant differences in the rates of infection, severe acute rejection, biliary tract complications, arterial/portal thrombosis and mental complications between the two groups (all P>0.05). The rate of renal replacement therapy for acute kidney injury in the observation group (9.8%, 5/55) was significantly higher than that in the control group (1.3%, 2/155) ( P<0.05). Conclusion:Ligation of splenic artery during liver transplantation was safe and it had a significant advantage in the early postoperative recovery of WBC count and creatinine without increasing the incidence of complications in patients with severe hypersplenism.

14.
Chinese Journal of Hospital Administration ; (12): 953-957, 2021.
Article in Chinese | WPRIM | ID: wpr-934538

ABSTRACT

Talent evaluation is the premise of development management and the use of human resources. The establishment of the talent classification and evaluation mechanism of university affiliated hospitals plays an important role in setting up the correct employment orientation, stimulating the career development of talents and promoting the high-quality development of public hospitals. The authors took the perspective of university affiliated hospitals, summed up the construction process of talent evaluation system in China, analyzed the existing problems in evaluation indicators, evaluation methods and operation mechanism of talent evaluation system, and came out with suggestions that the national level should strengthen the top-level design and collaborative management of talent evaluation, the hospital level should refine the evaluation indicators, improve the evaluation methods and establish the concept of developmental evaluation, at meanwhile, schools should improve the talent management mechanism and strengthen the function of audit and supervision.

15.
Acta Pharmaceutica Sinica B ; (6): 289-300, 2020.
Article in English | WPRIM | ID: wpr-787628

ABSTRACT

Gliomas are the most common primary intracranial neoplasms among all brain malignancies, and the microtubule affinity regulating kinases (MARKs) have become potential drug targets for glioma. Here, we report a novel dual small-molecule inhibitor of MARK3 and MARK4, designated as PCC0208017. PCC0208017 strongly inhibited kinase activity against MARK3 and MARK4, and strongly reduced proliferation in three glioma cell lines. This compound attenuated glioma cell migration, glioma cell invasion, and angiogenesis. Molecular mechanism studies revealed that PCC0208017 decreased the phosphorylation of Tau, disrupted microtubule dynamics, and induced a G2/M phase cell cycle arrest. In an glioma model, PCC0208017 showed robust anti-tumor activity, blood-brain barrier permeability, and a good oral pharmacokinetic profile. Molecular docking studies showed that PCC0208017 exhibited high binding affinity to MARK3 and MARK4. Taken together, our study describes for the first time that PCC0208017, a novel MARK3/MARK4 inhibitor, might be a promising lead compound for treatment of glioma.

16.
Chinese Journal of School Health ; (12): 1678-1681, 2020.
Article in Chinese | WPRIM | ID: wpr-837592

ABSTRACT

Objective@#To investigate the relationship between different physical activity pattern and trajectories of anxiety and depression scores in college students, and to provide evidence for exploring the influence of physical activity on the development of anxiety and depression.@*Methods@#A total of 1 265 college students from grade 2017 in a comprehensive university were investigated longitudinally for five times through stratified cluster sampling. Physical Activity Rank Scale-3(PARS-3), Self-rating Anxiety Scale(SAS), and Self-rating Depression Scale(SDS) were used, and latent class linear mixed models(LCLMM) were used to identify the trajectories of anxiety and depression scores and multinomial Logistic regression models were used for exploring the relationship between small persistent status of physical activity among the five surveys and subgroups of trajectory and anxiety and depression scores.@*Results@#A total of 940(74.3%) college students were indentified as low persistent physical activity group and 325(25.7%) of them were identified as moderatre-to-high persistent physical activity group. The trajectories of anxiety score were classified into three groups:low level group, high level-decreasing group, and high level group. The number and proportion of the three groups were 686(54.2%), 144(11.4%), 435(34.4%), respectively. The trajectories of depression score were classified into four groups:low level group, moderate level-decreasing group, moderate level-increasing group, and high level group. The number and proportion of the five groups were 604(47.8%), 170(13.4%), 177(14.0%), 314(24.8%), respectively. Compared to the students with moderate-to-high persistent physical activity, higher persistent physical activity was associated with higher risk of keeping anxiety score at a high level(OR=1.78), and higher odds of decreasing depression score at moderate level(OR=0.67), as well as with higher risk of increasing depression score from a moderate level(OR=1.79), and increase the risk of keeping depression score at a high level(OR=1.97)(P<0.05).@*Conclusion@#Low persistent physical activity of college students could increase the risk of anxiety and depression at a high level. Relevant departments in universities should encourage students to take part in physical activity,with special focus given to individuals with less amount of physical activity and take effective interventional measures to modify the development of anxiety and depression.

17.
Chinese Journal of Hospital Administration ; (12): 881-885, 2020.
Article in Chinese | WPRIM | ID: wpr-872388

ABSTRACT

General hospitals play an important role in the prevention and control of emerging infectious diseases, making it imperative to stand by for outbreaks of epidemics in peacetime. This study analyzed the necessity of the mechanism of adapting these hospitals to both peacetime and wartime against emerging infectious diseases. In addition, the authors identified existing problems in dealing with emerging infectious diseases, and put forward corresponding suggestions: readiness in the conversion into epidemic-control; strengthened comprehensive prevention and control of nosocomial infection; strengthened construction of epidemic prevention teambuilding; an emergency material supply guarantee mechanism; an optimized monitoring and early warning mechanism; enhanced risk management and joint prevention and control.

18.
Chinese Journal of Hospital Administration ; (12): 349-352, 2020.
Article in Chinese | WPRIM | ID: wpr-872256

ABSTRACT

Objective:To analyze the current situation and characteristics of online public sentiments faced by public hospitals since the outbreak of COVID-19, and provide suggestions for coping strategies for such hospitals.Methods:The data of " trending topic" or " Trending hash tag" of " Wuhan Union Hospital" and " anti-epidemic" were captured on three mainstream new media platforms, namely Sina Microblog, Tik Tok and Headline Today with the help of data analysis tools of Sina and online data statistical software from December 2019 to February 2020. Content analysis method was used to analyze the occurrence frequency, time distribution and development trend of public sentiment on Internet.Results:Under the epidemic of COVID-19, public hospitals faced an exponential growth of online public sentiment. The cumulative total number of searches was 72 119 802 tens of thousands of that before the epidemic. The transmission showed fragmentation of content, instantaneous speed and higher attention to negative information, which brought great challenges for public hospitals.Conclusions:The high participation of online discussion of COVID-19 is unprecedented. Thus public hospitals should attach importance to the work related to online public sentiment, and establish corresponding coping mechanism for response.

19.
Chinese Journal of Orthopaedics ; (12): 1098-1108, 2020.
Article in Chinese | WPRIM | ID: wpr-869065

ABSTRACT

Objective:To compare the effect of the new anterior cervical spine memory compression fixation device (GYZ memory alloy plate) and traditional titanium plate on the range of motion (ROM) and stress of the adjacent segment after anterior cervical discectomy and fusion.Methods:An adult male volunteer was recruited for a fee. After excluding cervical malformations, fractures, infections and other diseases, C 3-C 7 thin-layer CT scans were performed. Import the scanned data into the finite element modeling software to establish the finite element model of the physiological group and verify itseffectiveness. After C 5,6 discectomy, the intervertebral fusion device was inserted, and the anterior fixation was assisted by a conventional titanium plate or a new type of fixator. Thus, the finite element model of the traditional titanium plate group and the new fixer group was established. The three models were imported into the finite element analysis software ANSYS 16.0, and a vertical downward axial load of 73.6 N was loaded to simulate the head weight and the torque of 1.0 N·m to simulate the cervical spine flexion, extension, left lateral bending, right lateral bending, left rotation and right rotation.Compare the changes of intervertebral disc ROM and stress in adjacent segments of physiological group, traditional titanium plate group and new type fixator group. Results:The intervertebral disc ROM under six conditions was basically similar to the results of previous studies, and the model was effective. In the adjacent segment C 4,5, the three groups of activities in the flexion, extension, left lateral bending, right lateral bending, left rotation and right rotation conditions were: physiological group 3.9°, 4.2°, 3.7°, 3.7°, 2.2° and 2.2°, traditional titanium plate group 4.6°, 4.7°, 4.3°, 4.4°, 3.3° and 3.1°, and new fixture group 4.4°, 4.3°, 4.0°, 4.2°, 2.8° and 2.7°. The maximum stresses of the intervertebral discs under three different working conditions were: physiological group 1.81, 1.60, 3.99, 2.06, 3.63 and 3.41 MPa, traditional titanium plate group 1.86, 1.67, 4.21, 2.16, 3.82 and 3.63 MPa, and new fixture group 1.84, 1.64, 4.17, 2.14, 3.78 and 3.58 MPa. In the adjacent segment C 6,7, the activities of the three groups in six working conditions were: physiological group 3.1°, 3.2°, 2.5°, 2.5°, 1.2° and 1.3°, traditional titanium plate group 4.2°, 3.7°, 3.4°, 3.0°, 2.1° and 2.2°, and new fixture group 3.5°, 3.3°, 2.5°, 2.7°, 1.8° and 1.9°.The maximum stress of the intervertebral disc under three different working conditions was: physiological group 0.45, 0.66, 1.12, 0.85, 0.84 and 0.82 MPa, traditional titanium plate group 0.62, 0.93, 1.55, 1.24, 1.44 and 1.27 MPa, and new fixture group 0.61, 0.92, 1.54, 1.22, 1.07 and 1.24 MPa. The ROM and disc pressure of adjacent segments in the conventional titanium plate group were higher than those of the new fixator group. Conclusion:Compared with the traditional titanium plate, the new type of anterior cervical memory compression fixator has less effect on the ROM and stress of adjacent segments, which may slow down the process of adjacent segments degeneration to a certain extent.

20.
Chinese Journal of Trauma ; (12): 885-891, 2020.
Article in Chinese | WPRIM | ID: wpr-867800

ABSTRACT

Objective:To investigate the processing accuracy and biomechanical properties of 3D printed artificial bone trabeculae with different porosity generated by the Voronoi Tessellation algorithm, and to provide a reference for improving the biomechanical properties of titanium alloy implants in orthopedics.Methods:A healthy adult male volunteer (aged: 30 years, tall: 175 cm and weight: 70 kg) was selected to collect CT scan data of the lumbar spine. Five kinds of biomimetic artificial bone trabeculae with different porosity were generated using the Voronoi Tessellation algorithm, and divided into Tra_A (73.7%), Tra_B (74.1%), Tra_C (80.0%), Tra_D (80.2%) and Tra_E (85.7%) groups according to the porosity. Selective laser melting (SLM) 3D printing technology was used to process trabecular bone structures with different porosity into titanium alloy prosthesis with a diameter of 18 mm and a height of 20 mm. Each group had 3 samples. The internal structure of each sample was observed by industrial microscope, and the actual porosity of artificial bone trabecular of each group was calculated and compared with the theoretical porosity to evaluate the machining accuracy of artificial bone trabecular with different porosity. Finally, the ultimate load, yield strength and elastic modulus of each sample were evaluated by in vitro mechanical test, and the biomechanical properties of artificial bone trabeculae with different porosity were evaluated.Results:There were no cracks, fracture of connecting rod or accumulation of titanium alloy powder in all specimens. The average actual porosity of the five groups of artificial bone trabecular specimens was 66.0%, 65.5%, 71.8%, 72.5% and 78.1%, respectively. Compared with the theoretical porosity, it was smaller by 10.5%, 11.6%, 10.2%, 9.7% and 8.8%, respectively. In the in vitro mechanical tests for the five groups of artificial bone trabecular specimens, the mean value of ultimate load was 23.6 kN, 18.9 kN, 17.0 kN, 16.3 kN, 10.7 kN, respectively; the mean value of yield strength was 72.2 MPa, 58.7 MPa, 54.9 MPa, 52.2 MPa, and 36.1 MPa, respectively; the mean value of the actual elastic modulus was 7.5 GPa, 6.3 GPa, 4.5 GPa, 4.3 GPa and 2.4 GPa, respectively. With the increase of the porosity of artificial bone trabeculae, all three indicators above showed a decreasing trend. Conclusions:The artificial bone trabeculae generated by the Voronoi Tessellation algorithm and printed by SLM 3D have better machining quality. With the increase of porosity, the processing precision of the titanium alloy artificial bone tray specimens is better. Limit load, yield light and elastic modulus of artificial bone trabecula decrease with the increase of porosity.

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