With the optimization of surgical technologies and postoperative management regimens, the number of lung transplantation has been significantly increased, which has become an important treatment for patients with end-stage lung disease. However, due to the impact of comprehensive factors, such as bronchial ischemia and immunosuppression, the incidence of airway stenosis after lung transplantation is relatively high, which severely affects postoperative survival and quality of life of lung transplant recipients. In recent years, with the improvement of perioperative management, organ preservation and surgical technologies, the incidence of airway stenosis after lung transplantation has been declined, but it remains at a high level. Early diagnosis and timely intervention play a significant role in enhancing clinical prognosis of patients with airway stenosis. In this article, the general conditions, diagnosis, treatment and prevention of airway stenosis after lung transplantation were reviewed, aiming to provide reference for comprehensive management of airway stenosis after lung transplantation and improving clinical prognosis of lung transplant recipients.

Streptococcus parasuis(S.parasuis)is a close relative of S.suis and can cause meningi-tis,pneumonia or systemic symptoms in affected animals.In this paper,the dominant strain was i-solated from diseased pigs with pneumonia in Jilin,China,and the isolated strain was identified as S.parasuis by 16S rRNA,it was named WYF-8B.Resistance was tested by the susceptibility tablet diffusion method,and WYF-8B was resistant to bacitracin,sulfamethoxoprim,lincomycin,erythro-mycin,fosfamycin,azithromycin,penicillin,doxycycline,cotrimotrixazole,sulfamisoxazole,cipro-floxacin,enrofloxacin,tetracycline,benzoxacillin,gentamicin,efazolin,and ampicillin.It was highly sensitive to florfenicol,chloramphenicol.Iochemical identification revealed that WYF-8B could fer-ment salicylic acid,maltose,lactose,sucrose,oxaesin,and glucose;nonfermentable mannitol,urea,raffinose,xylose,arabinose,and sorbitol.Using the second-generation whole-genome sequencing technology to study the WYF-8B resistant genotype,it was found that it carried the macrolide anti-biotic resistance genes Mef(E)and ErmB;resistance genes pbp2b,pbp1a,and pbp2x to β-lactam antibiotics;resistance genes gyrA,parC,and grlB to fluoroquinolones;resistance genes ANT(6)-Ia,AAC(6')-Ie-APH(2')-Ia,ANT(9)-Ia,APH(3')-Ⅲa to aminoglycoside antibiotics;re-sistance groups lnuB,lmrC,lmrD against lincomide antibiotics;resistance gene tetM to tetracy-cline antibiotics;the resistance gene of bacitracin,bcrA.The results found that the resistance phe-notype matches the resistance genotype of the sequencing results.The study of WYF-8B virulence factors found that WYF-8B carried 13 virulence factors(pavA,fbp 54,clpP,cps 4,cps 4 I,wbtB,cps,sI,tufA,galE,hasC,groEL,wrbtL,wbbtF),which mainly acted to promote bacterial diffu-sion,transfer,settlement,antiphagocytosis and immune evasion.The results of drug sensitivity test provide a reference for the study of clinical medication of S.parasuis,and drug resistance pheno-type and virulence factors lay the foundation for the research and development of new drugs and vaccines.

Objective:To explore the current status of surgery for portal hypertension to grasp current status and future development of surgery in China.Methods:This study is jointly sponsored by China Hepatobiliary & Pancreatic Specialist Alliance & Portal Hypertension Alliance in China (CHESS).Comprehensive surveying is conducted for basic domestic situations of surgery for portal hypertension, including case load, surgical approaches, management of postoperative complications, primary effects, existing confusion and obstacles, liver transplantation(LT), laparoscopic procedures and transjugular intrahepatic portosystemic shunt(TIPS), etc.Results:A total of 8 512 cases of portal hypertension surgery are performed at 378 hospitals nationwide in 2021.Splenectomy plus devascularization predominated(53.0%)and laparoscopy accounted for 76.1%.Primary goal is preventing rebleeding(67.0%) and 72.8% of hospitals used preventive anticoagulants after conventional surgery.And 80.7% of teams believe that the formation of postoperative portal vein thrombosis is a surgical dilemma and 65.3% of hospitals practiced both laparoscopy and TIPS.The major reasons for patients with portal hypertension not receiving LT are due to a lack of qualifications for LT(69.3%)and economic factors(69.0%).Conclusions:Surgery is an integral part of management of portal hypertension in China.However, it is imperative to further standardize the grasp of surgical indications, the handling of surgical operation and the management of postoperative complications.Moreover, prospective, multi-center randomized controlled clinical studies should be performed.

Parkinson's disease （PD） is a progressive chronic neurodegenerative disorder with a complex pathogenesis involving oxidative stress， neuroinflammation， mitochondrial dysfunction， and other factors. Currently， the clinical treatment of PD mainly includes levodopa， dopamine receptor agonists， monoamine oxidase B inhibitors， catechol-O-methyltransferase inhibitors， and anticholinergic drugs， but there is a lack of disease-modif g therapies that can definitively improve disease progression. According to the understanding of traditional Chinese medicine （TCM）， PD is characterized by asthenia in origin and sthenia in superficiality. It is primarily caused by liver-kidney Yin deficiency， Qi-blood insufficiency， and closely related to wind， fire， phlegm， and blood stasis. Numerous clinical practices have shown that TCM has significant clinical value in the prevention and treatment of PD， the management of motor and non-motor symptoms， and the neuroprotection of dopaminergic neurons. The underlying mechanisms of TCM include antioxidative stress， anti-neuroinflammation， and regulation of mitochondrial dysfunction. This article categorized and summarized the pathogenesis of PD， systematically elucidated the pharmacological actions and molecular mechanisms of TCM monomer extracts and compounds in the prevention and treatment of PD， and provided the latest clinical research progress， aiming to provide references for the development and clinical use of TCM for PD.

Objective:To explore the efficacy and safety of paclitaxel liposomes compared to paclitaxel with platinum in concurrent chemoradiotherapy for unresectable cervical carcinoma.Methods:SinoMed, CNKI, WanFang MED ONLINE, VIP, PubMed, MEDLINE, Cochrane Library, Embase and ClinicalTrials.gov were searched to collect the papers or clinical studies of paclitaxel liposomes and paclitaxel combined with platinum in concurrent chemoradiotherapy for unresectable cervical carcinoma from the inception to January 15th 2021 in Chinese and English. Two independent reviewers screened the literatures, extracted the data and assessed the bias of the included studies. Meta-analysis was performed using RevMan 5.4 and R software.Results:Totally 9 papers involving 666 patients with unresectable cervical carcinoma were included. The results of meta-analysis indicated that compared to paclitaxel combined with platinum in concurrent chemoradiotherapy for unresectable cervical carcinoma, paclitaxel liposomes combined with platinum exhibited superiority in near-term efficacy (complete response + partial response) [81.4%(272/334) vs 68.7%(228/332), RR=1.19; 95% CI: 1.09, 1.29, P=0.000 1]; substantially decreased the incidence rates of blood system disorders [myelosuppressio, 50.3%(168/334)vs 65.1%(216/332)], gastrointestinal disorders [34.4%(115/334) vs 55.1%(183/332)], alopecia [42.2%(94/223)vs 63.3%(140/221)], allergic reaction [11.6% (23/198)vs 27.6%(54/196), P≤0.000 1], peripheral neuritis [43.0%(52/121) vs 54.9%(67/122)], or joint and muscle pain [20.3%(16/79) vs 34.6%(28/81), P<0.050 0]. Conclusion:Compared to paclitaxel combined with platinum in concurrent chemoradiotherapy for unresectable cervical carcinoma, paclitaxel liposomes is superior in near-term efficacy, and exhibits better safety.

Objective:To explore the efficacy and safety of paclitaxel liposomes compared to paclitaxel with platinum in concurrent chemoradiotherapy for unresectable cervical carcinoma.Methods:SinoMed, CNKI, WanFang MED ONLINE, VIP, PubMed, MEDLINE, Cochrane Library, Embase and ClinicalTrials.gov were searched to collect the papers or clinical studies of paclitaxel liposomes and paclitaxel combined with platinum in concurrent chemoradiotherapy for unresectable cervical carcinoma from the inception to January 15th 2021 in Chinese and English. Two independent reviewers screened the literatures, extracted the data and assessed the bias of the included studies. Meta-analysis was performed using RevMan 5.4 and R software.Results:Totally 9 papers involving 666 patients with unresectable cervical carcinoma were included. The results of meta-analysis indicated that compared to paclitaxel combined with platinum in concurrent chemoradiotherapy for unresectable cervical carcinoma, paclitaxel liposomes combined with platinum exhibited superiority in near-term efficacy (complete response + partial response) [81.4%(272/334) vs 68.7%(228/332), RR=1.19; 95% CI: 1.09, 1.29, P=0.000 1]; substantially decreased the incidence rates of blood system disorders [myelosuppressio, 50.3%(168/334)vs 65.1%(216/332)], gastrointestinal disorders [34.4%(115/334) vs 55.1%(183/332)], alopecia [42.2%(94/223)vs 63.3%(140/221)], allergic reaction [11.6% (23/198)vs 27.6%(54/196), P≤0.000 1], peripheral neuritis [43.0%(52/121) vs 54.9%(67/122)], or joint and muscle pain [20.3%(16/79) vs 34.6%(28/81), P<0.050 0]. Conclusion:Compared to paclitaxel combined with platinum in concurrent chemoradiotherapy for unresectable cervical carcinoma, paclitaxel liposomes is superior in near-term efficacy, and exhibits better safety.

Stress distribution of denture is an important criterion to evaluate the reasonableness of technological parameters, and the bite force derived from the antagonist is the critical load condition for the calculation of stress distribution. In order to improve the accuracy of stress distribution as much as possible, all-ceramic crown of the mandibular first molar with centric occlusion was taken as the research object, and a bite force loading method reflecting the actual occlusal situation was adopted. Firstly, raster scanning and three dimensional reconstruction of the occlusal surface of molars in the standard dental model were carried out. Meanwhile, the surface modeling of the bonding surface was carried out according to the preparation process. Secondly, the parametric occlusal analysis program was developed with the help of OFA function library, and the genetic algorithm was used to optimize the mandibular centric position. Finally, both the optimized case of the mesh model based on the results of occlusal optimization and the referenced case according to the cusp-fossa contact characteristics were designed. The stress distribution was analyzed and compared by using Abaqus software. The results showed that the genetic algorithm was suitable for solving the occlusal optimization problem. Compared with the reference case, the optimized case had smaller maximum stress and more uniform stress distribution characteristics. The proposed method further improves the stress accuracy of the prosthesis in the finite element model. Also, it provides a new idea for stress analysis of other joints in human body.
Bite Force ; Ceramics ; Crowns ; Dental Stress Analysis ; Finite Element Analysis ; Humans ; Molar ; Prostheses and Implants ; Stress, Mechanical

As a representative part of the oral system and masticatory robot system, the modeling method of the dental model is an important factor influencing the accuracy of the multi-body dynamic model. Taking the right first molars of the masticatory robot as the research object, an equivalent model, point-contact higher kinematic pair composed of v-shaped surface and sphere surface, was proposed. Firstly, the finite element method was used to analyze the occlusal dynamics of the original model in three static contact cases (intrusive contact, centric occlusion, and extrusive contact) and one dynamic chewing case, and the expected bite force was obtained. Secondly, the Hertz contact model was adopted to establish the analytical expression of the bite force of the equivalent model in three static contact cases. The normal vectors and contact stiffness in the expression were designed according to the expected bite force. Finally, the bite force performance of the equivalent model in three static contact cases and one dynamic chewing case was evaluated. The results showed that the equivalent model could achieve the equivalent bite force of 8 expected items in the static contact cases. Meanwhile, the bite force in the early and late stages of the dynamic chewing case coincides well with the original model. In the middle stage, a certain degree of impact is introduced, but it can be weakened by subsequent trajectory planning. The equivalent modeling scheme of the dental model proposed in this paper further improves the accuracy of the dynamic model of the multi-body system. It provides a new idea for the dynamic modeling of other complex human contacts.
Biomechanical Phenomena ; Bite Force ; Humans ; Mastication ; Molar

Masticatory robots have a broad application prospect in the field of denture material tests and mandible rehabilitation. Mechanism type of temporomandibular joint structure is an important factor influencing the performance of the masticatory robot. In view of the wide application of elastic components in the field of the biomimetic robot, an elastic component was adopted to simulate the buffering characteristics of the temporomandibular joint disc and formed the elastic temporomandibular joint structure on the basis of point-contact high pair. Secondly, the influences of the elastic temporomandibular joint structure (on mechanism degree, kinematics, dynamics, etc.) were discussed. The position and velocity of the temporomandibular joint were analyzed based on geometric constraints of the joint surface, and the dynamic analysis based on the Lagrange equation was carried out. Finally, the influence of the preload and stiffness of the elastic component was analyzed by the response surface method. The results showed that the elastic temporomandibular joint structure could effectively guarantee the flexible movement and stable force of the joint. The elastic joint structure proposed in this paper further improves the biomimetic behavior of masticatory robots. It provides new ideas for the biomimetic design of viscoelastic joint discs.

Objective: To investigate the effect of repairing the skin and soft tissue defects of foot with the anterior tibial artery perforator flap. Methods: Nine patients received the operation using the anterior tibial artery periosteal perforator flap to repair distal foot lesion with skin and soft tissue defects.There were six males and three females.All cases were the distal foot defects of skin and soft tissue with tendon and bone exposure, including traffic accident injury in 5 cases, crush injury in 3 cases, other causes of injury in 1 case. The defects ranged from 5 cm×3 cm to 9 cm×6 cm. The flaps ranged from 7 cm×5 cm—11 cm×8 cm. The donor sites were repaired with direct suture or full-thickness skin grafts. Results: All the flaps were survived, without vascular crisis, congestion and blisters. 1 case had partial necrosis of flap margin, which was cured after dressing. All cases were followed up for 6 months to 34 months(mean 18 months). The appearance and function recovery of flaps were satisfactory. Conclusions It is an ideal flap donor site for repairing soft tissue defects of the distal foot with the anterior tibial artery perforator flap, which has the advantages of simple operation, less trauma, high skin flap survival rate and good appearance.