Neurodegenerative diseases(NDD)are a heterogeneous group of disorders characterized by neuronal degeneration and functional impairment,in which neuroinflammation plays a pivotal role throughout disease onset and progression.The 18 kDa translocator protein(TSPO)serves as an important molecular biomarker of neuroinflammation,with its expression closely associated with activation of microglia and astrocytes.TSPO-PET enables noninvasive and dynamic mapping of spatiotemporal distribution of cerebral neuroinflammation,providing crucial molecular imaging evidence for early diagnosis,disease evaluation and therapeutic response assessment of NDD.The advances and challenges of TSPO-PET imaging in NDD were reviewed in this article.

Neurodegenerative diseases(NDD)are a heterogeneous group of disorders characterized by neuronal degeneration and functional impairment,in which neuroinflammation plays a pivotal role throughout disease onset and progression.The 18 kDa translocator protein(TSPO)serves as an important molecular biomarker of neuroinflammation,with its expression closely associated with activation of microglia and astrocytes.TSPO-PET enables noninvasive and dynamic mapping of spatiotemporal distribution of cerebral neuroinflammation,providing crucial molecular imaging evidence for early diagnosis,disease evaluation and therapeutic response assessment of NDD.The advances and challenges of TSPO-PET imaging in NDD were reviewed in this article.

Internet hospitals played a huge role in meeting patients’ medical needs during the COVID-19 pandemic. As a new service model, it also brings new challenges to medical ethics. This paper analyzed the three key elements of behavior: actors, behavior process and action result, and found that apart from ethical challenges such as medical security, data security and privacy protection, different types of Internet hospitals show diversity due to different actors involved. The first type of Internet hospital represented the conflict of interest of doctors brought by the integration of offline and online working modes. The second type showed the challenge of fairness in medical treatment brought by the demand of personalized service provided by medical staff in public medical institutions. The third type manifested the medical security challenges brought by doctors with varying technical levels in an open platform environment. Combined with the current ethical governance of science and technology and the digital transformation of society, this paper put forward some countermeasures and suggestion, such as further clarifying the boundaries of rights and responsibilities of relevant subjects of Internet platform, formulating the code of conduct requirements for medical staff in Internet hospitals, and supervising doctors’ medical practice in Internet hospitals.

Objective:To assess impact of radiation from nuclear power on the surrounding environment, a dose assessment model was constructed and relevant dose coefficients were determined through refined animal models.Methods:Zebrafish is one of the most important aquatic model animals in the radiation hazard assessment of nuclear power liquid effluent. A geometric model of zebrafish containing internal bones and visceral organ was established for dose estimation. The internal and external dose coefficients (DC) of the zebrafish model were calculated by Monte Carlo method with seven nuclides as the source term, 3H, 40K, 58Co, 60Co, 110Ag, 134Cs, 137Cs, which are common in nuclear liquid effluents and environmental monitoring. Results:The level of nuclide gamma energy determines dose coefficients for external radiation. The dose coefficients of most nuclides in internal organs was higher than that in whole body, and the internal organ dose of 58Co was 165% higher than that in whole body. The internal radiation dose coefficients of the model established in this study was relatively high, and the internal radiation dose coefficients caused by 60Co was 2.6 times of existing ellipsoid model, which suggested that the different internal materials and the choice of different particle types would affect the energy deposition. Conclusions:Refining of model animals is important. Accurate assessment of the organs dose coefficients of model animals is helpful to assess the radiation effects on non-human species.

Objective:To examine the clinical effects of the treatment of knee osteoarthritis patients with kinematic alignment technique of total knee replacement (KA-TKA) assisted by patient-specific instrumentation (PSI).Methods:The clinical data of 14 patients with knee osteoarthritis treated with unilateral KA-TKA assisted by PSI at Department of Orthopaedic Surgery, Beijing Chaoyang Hospital Affiliated to Capital Medical University from May 2018 to August 2019 were analyzed retrospectively. There were 6 males and 8 females, aged 66.6 years (range: 56 to 79 years), 9 left knees and 5 right knees. The operation time, soft tissue release and extra varus or valgus osteotomy were recorded. The data of osteotomy blocks were measured and compared with the corresponding position of the prostheses. The hip knee ankle angle (HKA), the mechanical distal femoral lateral angle (mLDFA) and the proximal tibial medial angle (MPTA) were measured before and 3 months after the operation. The knee joint functional score (KS-F) , knee joint clinical score (KS-C) and the Western Ontario McMaster (WOMAC) Osteoarthritis Index were recorded and compared by paired t test or Wilcoxon non-parametric test. Results:The operation time was (81.8±16.9) minutes (range: 60 to 115 minutes), 2 cases were manually increased varus osteotomy by 2 mm and 1 patient received lateral retinaculum release. There was no extra medial or lateral soft tissue release. Intraoperative measurement of the resection showed that the femoral side mismatch was within 2 mm. The medial and lateral condyle, the medial and lateral posterior condyles were relatively overcut by 0.50 mm, 0.21 mm, 0.93 mm, and 0.71 mm, respectively. The tibial side mismatch was within 1.5 mm, the medial and lateral plateau were relatively undercut by 0.43 mm and 0.32 mm. HKA was corrected from (8.8±5.6) ° to (1.6±4.3) ° ( t=20.723, P=0.000) .KS-C improved from 28.21±13.47 preoperative to 78.07±8.01 postoperative ( t=-16.570, P=0.000); KS-F improved from 41.00±15.25 preoperative to 84.93±10.85 postoperative ( t=-14.675, P=0.000).WOMAC Osteoarthritis Index decreased from 53.5 (25.75) ( M( QR)) preoperative to 5.5 (5.25) postoperative ( Z=-3.297, P=0.001) .No statistically significant difference was found in mLDFA and MPTA before and after surgery. No significant patellofemoral complication was recorded during follow-up time. Conclusions:PSI assisted TKA resection has high accuracy. KA-TKA aims to restore the native anatomy of the knee joint, only corrects the malalignment of lower extremities caused by articular cartilage wear, with less interference to soft tissues, easy to obtain satisfactory knee joint laxity and has a promising early clinical effect.

Objective: To discuss the surgical technique of lateral unicondylar knee replacement (UKR) for patients with lateral compartment osteoarthritis and evaluate its recent clinical efficacy. Methods: A retrospective analysis was conducted on 22 cases of lateral compartment osteoarthritis patients receiving lateral UKR at Orthopedic Department, Beijing Chao Yang Hospital, Capital Medical University from January 2016 to January 2019.There were 8 males (8 knees) and 14 females (14 knees), aged 65.7 years(range: 54 to 83 years).All patients completed preoperative imaging examination and excluded extra-articular deformity.Lateral parapelatellar approach was used for the operation and the tibial osteotomy was performed by extramedullary positioning.The residual cartilage of the external condyle was removed by pendulum saw to subchondral bone.Appropriate prosthesis were selected, and the tightness of the gap and the stability of the joints were repeatedly confirmed during the operation.The postoperative complications and the results of physical and imaging examinations were collected.The preoperative and postoperative Oxford knee Score (OKS) and knee society score (KSS) of patients were recorded and compared by paired t test. Results: All patients were followed up for 24.6 months (range: 8 to 40 months).No complications such as incision exudation, skin necrosis and deep venous thrombosis of lower limbs were found after the operation.No cases of prosthesis loosening, excessive wear of pads, dislocation and postoperative infection were found at the last follow-up.The OKS decreased from 46.5±3.1 preoperative to 22.4±3.3 postoperative(t=13.4, P=0.00) and KSS improved from 69.5±8.7 preoperative to 90.2±7.4 postoperative (t=16.9, P=0.00) . Conclusions For the treatment of lateral compartment osteoarthritis, UKR has the advantages of rapid recovery of knee function, less complications and less trauma.The short-term efficacy is satisfactory, but the long-term efficacy remains to be observed.

Objective:To examine the clinical effects of the treatment of knee osteoarthritis patients with kinematic alignment technique of total knee replacement (KA-TKA) assisted by patient-specific instrumentation (PSI).Methods:The clinical data of 14 patients with knee osteoarthritis treated with unilateral KA-TKA assisted by PSI at Department of Orthopaedic Surgery, Beijing Chaoyang Hospital Affiliated to Capital Medical University from May 2018 to August 2019 were analyzed retrospectively. There were 6 males and 8 females, aged 66.6 years (range: 56 to 79 years), 9 left knees and 5 right knees. The operation time, soft tissue release and extra varus or valgus osteotomy were recorded. The data of osteotomy blocks were measured and compared with the corresponding position of the prostheses. The hip knee ankle angle (HKA), the mechanical distal femoral lateral angle (mLDFA) and the proximal tibial medial angle (MPTA) were measured before and 3 months after the operation. The knee joint functional score (KS-F) , knee joint clinical score (KS-C) and the Western Ontario McMaster (WOMAC) Osteoarthritis Index were recorded and compared by paired t test or Wilcoxon non-parametric test. Results:The operation time was (81.8±16.9) minutes (range: 60 to 115 minutes), 2 cases were manually increased varus osteotomy by 2 mm and 1 patient received lateral retinaculum release. There was no extra medial or lateral soft tissue release. Intraoperative measurement of the resection showed that the femoral side mismatch was within 2 mm. The medial and lateral condyle, the medial and lateral posterior condyles were relatively overcut by 0.50 mm, 0.21 mm, 0.93 mm, and 0.71 mm, respectively. The tibial side mismatch was within 1.5 mm, the medial and lateral plateau were relatively undercut by 0.43 mm and 0.32 mm. HKA was corrected from (8.8±5.6) ° to (1.6±4.3) ° ( t=20.723, P=0.000) .KS-C improved from 28.21±13.47 preoperative to 78.07±8.01 postoperative ( t=-16.570, P=0.000); KS-F improved from 41.00±15.25 preoperative to 84.93±10.85 postoperative ( t=-14.675, P=0.000).WOMAC Osteoarthritis Index decreased from 53.5 (25.75) ( M( QR)) preoperative to 5.5 (5.25) postoperative ( Z=-3.297, P=0.001) .No statistically significant difference was found in mLDFA and MPTA before and after surgery. No significant patellofemoral complication was recorded during follow-up time. Conclusions:PSI assisted TKA resection has high accuracy. KA-TKA aims to restore the native anatomy of the knee joint, only corrects the malalignment of lower extremities caused by articular cartilage wear, with less interference to soft tissues, easy to obtain satisfactory knee joint laxity and has a promising early clinical effect.

Objective To evaluate clinical treatment efficacy of double?row fixation with bridging suture anchors for chronic, severe patellar tendinopathy. Methods A retrospective study of 18 patients suffered from severe patellar tendinopathy and underwent surgical treatment during January 2009 and June 2014 at Department of Orthopedic, Beijing Chao Yang Hospital, Capital Medical University was conducted.All patients had received conservative therapy for more than 6 months(range:6-30 months) but the effect was unsatisfactory. There were 10 males(12 knees) and 8 females(12 knees)with age of 47.2 years(range: 32-63 years). Seven cases on the left and 17 cases on the right. The surgical treatment included a midline incision at patellar tendon,complete debridement,and double?row fixation with bridging suture anchors. Visual analogue scale(VAS),Lysholm score were collected preoperatively and postoperatively, and compared by paired?t test. The postoperative complications was recorded. Results All patients were followed up for 35.7 months (range:24-64 months) without any dropout.VAS decreased from 7.5± 1.6 preoperative to 1.4±1.0(t=4.45,P=0.00) postoperative, Lysholm score increased from 48.3±5.2 to 89.6± 5.4 (t=-4.88,P=0.00).The Lysholm score was excellent in 3 cases and good in 15 cases.No patellar tendon rupture or suture fixation failure was recorded during the follow?up period. Conclusions The effect of double?row fixation with bridging suture anchors is satisfactory with few postoperative complications.It can not only improve clinical symptoms of patients,but also restore knee joint function.

Objective To explore the effect of Dexmedetomidine (Dex) on acute brain edema in mice in condition with targeted temperature management (TTM) following traumatic brain injury (TBI).Methods A total of 180 male C57BL/6J mice were divided into control group,sham operation group,TBI group,TBI + Dex group,TBI + TTM group,and TBI + Dex + TTM group according to the random number table (n =30 per group).The sham operation group only opened the bone window but did not hit it,and the control group did not open the bone window.The TBI + Dex,TBI + TIM,and TBI + Dex + TTM groups were intraperitoneally injected with Dex (60 μg/kg once every 2 h for 3 times) and/or hypothermia after TBI.The brain tissue injury volume,EB extravasation and brain water content of each group were determined by toluidine blue,Evans blue staining and dry-wet weight method at 24 hours after injury.Real-time quantitative PCR and Western blot were used to detect the expression of Claudin-5 in the injured brain tissue.At 24,48,and 72 hours after injury,the neurological deficiency degree was assessed using the modified neurological severity scores (mNSS).Results Compared with the sham operation group,TBI mice showed significant increase in brain tissue injury volume [(0.49 ± 0.04)mm3 vs.(1 1.57 ± 1.01)mm3],blood-brain barrier permeability [(16.4 ± 0.8) μg/g vs.(54.3 ± 1.7) μg/g],brain tissue water content [(76.7 ± 0.9) ％ vs.(83.1 ± 0.8) ％],and mNSS score [(1.6 ± 0.7) points vs.(13.4 ± 0.7) points] at 24 hour after TBI (all P ＜ 0.01).However,Dex or TTM treatment reduced brain tissue injury volume [(7.20±0.18)mm3 and (5.94 ±0.18)mm3],blood-brain barrier permeability [(32.7 ± 1.2) μg/g and (27.6 ± 1.0) μg,/g],brain tissue water content [(78.5 ± 0.4) ％ and (78.2 ± 0.6) ％],and neurological function [mNSS:(7.3 ± 1.1) points and (5.8 ± 1.3) points] (all P＜0.01).Moreover,Dex + TTM group showed better neuroprotection [reduced brain tissue injury volume:(3.92 ± 0.05) mm3,reduced BBB permeability:(21.6 ± 0.7) μg/g,reduced brain water content:(77.7 ±0.3)％,and reduced mNSS:(4.3 ± 1.2) points] compared with Dex or TTM alone (all P ＜ 0.01).Additionally,the mRNA expression of Claudin-5 (0.23 ± 0.01) decreased significantly at 24 hours after TBI compared with sham group (0.93 ± 0.04,P ＜ 0.01),but Dex or TTM could increase the expression of Claudin-5 (0.47 ± 0.01,and 0.54 ± 0.09) compared with TBI group (P ＜0.01),especially that of TBI + Dex + TTM group (0.64 ± 0.02,P ＜ 0.01).Furthermore,the protein expression of Claudin-5 was in accordance with the result of its mRNA expression.Conclusion Dex in condition with targeted temperature management can up-regulate Claudin-5 expression in early TBI,protect the integrity of blood-brain barrier,attenuate acute brain edema and neurological damage,and improve neurological function recovery.

Objective: To evaluate clinical treatment efficacy of double-row fixation with bridging suture anchors for chronic, severe patellar tendinopathy. Methods: A retrospective study of 18 patients suffered from severe patellar tendinopathy and underwent surgical treatment during January 2009 and June 2014 at Department of Orthopedic, Beijing Chao Yang Hospital, Capital Medical University was conducted. All patients had received conservative therapy for more than 6 months(range: 6-30 months) but the effect was unsatisfactory. There were 10 males (12 knees) and 8 females (12 knees)with age of 47.2 years(range: 32-63 years). Seven cases on the left and 17 cases on the right. The surgical treatment included a midline incision at patellar tendon, complete debridement, and double-row fixation with bridging suture anchors. Visual analogue scale(VAS), Lysholm score were collected preoperatively and postoperatively, and compared by paired-t test. The postoperative complications was recorded. Results: All patients were followed up for 35.7 months (range:24-64 months) without any dropout.VAS decreased from 7.5±1.6 preoperative to 1.4±1.0 (t=4.45, P=0.00) postoperative, Lysholm score increased from 48.3±5.2 to 89.6±5.4 (t=-4.88,P=0.00).The Lysholm score was excellent in 3 cases and good in 15 cases.No patellar tendon rupture or suture fixation failure was recorded during the follow-up period. Conclusions The effect of double-row fixation with bridging suture anchors is satisfactory with few postoperative complications.It can not only improve clinical symptoms of patients, but also restore knee joint function.