Tenascin-C (TNC), an extracellular matrix glycoprotein, is lowly expressed in normal adult tissues while significantly upregulated under pathological conditions such as injury, inflammation, or tumors. Recent studies have shown that TNC plays an important role in Alzheimer's disease (AD) development: it is not only closely related to the formation of β-amyloid (Aβ) plaque, but also involved in neuroinflammation regulation and Aβ clearance process. This article reviews the effect of TNC on AD pathology in aspects of neuroinflammation, synaptic function, autophagy and Aβ load, aiming to provide theoretical basis for TNC-targeted AD treatment and drug development.

Tenascin-C (TNC), an extracellular matrix glycoprotein, is lowly expressed in normal adult tissues while significantly upregulated under pathological conditions such as injury, inflammation, or tumors. Recent studies have shown that TNC plays an important role in Alzheimer's disease (AD) development: it is not only closely related to the formation of β-amyloid (Aβ) plaque, but also involved in neuroinflammation regulation and Aβ clearance process. This article reviews the effect of TNC on AD pathology in aspects of neuroinflammation, synaptic function, autophagy and Aβ load, aiming to provide theoretical basis for TNC-targeted AD treatment and drug development.

The medical metaverse is a combination of medicine and other cutting-edge technologies such as computer and information ones. In the medical metaverse, medical knowledge in the real world will be transformed into a digital form, so that activities concerning diagnosis, treatment, education and clinical practice can be carried out in a virtual environment. Based on the latest research advances at home and abroad, this review expounds on the medical metaverse from the aspects of supporting technologies, applications in clinic and medical education, current deficiencies and future development.

Objective To investigate the in vivo stress distribution of the atherosclerotic plaque at carotid bifurcation, so as to provide references for the mechanical mechanisms of plaque rupture at carotid bifurcation and the design for further medical treatment. Methods The three-dimensional geometric model of carotid bifurcation and plaque were established according to average geometric parameters of human carotid bifurcation. Residual stress of the carotid bifurcation and plague was reestablished with “thermal-structure” coupling method, and in vivo stresses of vessels with the plaque at carotid bifurcation under blood pressure and blood flow were calculated. Results Both the maximum principal stress and elastic shear stress concentrated on the shoulder of the plaque. Elastic shear stress increased with the increase of stenosis ratio and blood pressure. Wall shear stress in the upstream of the plaque was considerably higher than that of the downstream. The distribution of oscillatory shear index(OSI) was quite the opposite. The changing patterns of the elastic shear stress and flow shear stress were quite different with the change of stenosis ratios. Conclusions Tension grew gradually from the centrality to shoulder surface of the plaque. The centrality of the plaque might bear compression when the stenosis was very severe. The periodic variation of the structural stress might cause structural fatigue of the plaque, thus increasing the rupture risk. Distinction of the component and vulnerability of the plaque between upstream and downstream might be caused by differences in hemodynamic parameters of the plaque between upstream and downstream.

Objective To investigate the clinical efficacy of tibiocalcaneal arthrodesis using bone transport technique in the treatment of traumatic talus infection or loss. Methods A retrospective case series study was conducted to analyze the clinical data of 15 patients with talus infection or loss admitted to the provincial hospital affiliated to Shandong University from June 2011 to October 2017. There were 13 males and two females, aged from 19 to 47 years, with an average age of 27 years. Thirteen patients had talus infection and two patients had talus loss. All patients underwent tibiocalcaneal fusion with external fixator using bone transport technique, including four patients treated with annular external fixator and 11 with unilateral external fixator. Six patients with severe infection underwent debridement at stage I and osteotomy at stage II, and the other nine underwent debridement and osteotomy at the same time. The length of new bone, the fixation time of external fixator and complications were recorded. The American Orthopedic Foot and Ankle Society ( AOFAS ) score was used to evaluate the efficacy. Results All patients were followed up for 18-35 months, with an average of 26 months. The length of new bone in proximal tibial osteotomy area was 5-16 cm, with an average of 9 cm. The external fixators were removed after bone healing at docking site and maturation of new bone. The fixation time of external fixator ranged from 13 to 27 months, with an average of 18 months. No complications such as needle breakage, recurrence of infection and calcaneal varus occurred, and the length of both lower limbs was equal. AOFAS score was increased from preoperative (42. 0 ± 3. 6)points (31-55 points) to (76. 0 ± 4. 2)points (69-86 points ) at the last follow-up. Conclusion Tibiocalcaneal arthrodesis using bone transport technique is proved to be effective in treating traumatic talus infection or loss, which can repair the bone defect after debridement, improve the ankle-hindfoot function and improve the quality of life.

Objective To investigate the clinical outcomes of extraperitoneal pelvic packing combined with temporary occlusion of abdominal aorta in treatment of pelvic fractures with hemodynamic instability.Methods A retrospective case series study was made on 14 patients with pelvic fractures with hemodynamic instability managed by extraperitoneal pelvic packing plus temporary occlusion of abdominal aorta between December 2006 and December 2013.There were ten males and four females,with mean age of 38.2 years old (range,18-63 years).The fractures were classified according to the Tile classification,including two patients with type B1,two with type B2.2,one with type C1.1,two with type C1.2,two with type C1.3,three with type C2,and two with type C3.In addition,10 patients were with closed pelvic fractures and four with open pelvic fractures.All patients were diagnosed as hypovolemic shock once they were admitted.Every patient was given anti-shock treatment,temporary occlusion of abdominal aorta,and extraperitoneal pelvic packing instantly,in order to control hemorrhage of pelvic fracture after they were admitted.The operation time,red blood cell transfusion volume,preoperative and postoperative blood pressures,heart rates as well as other relevant parameters concerning death and survival were recorded and compared.Postoperative infection and wound healing status were recorded as well.Results The operation time was 50-70 minutes (mean,61 minutes).After surgery,the length of ICU stay was (10.9 ± 9.8) days and hospital stay was (23.1 ± 14.9) days.Red blood cell transfusion volume before and after surgery was (17.7 ± 2.2)U and (8.4± 1.7)U,respectively (P ＜ 0.05).The parameters of systolic pressures varied from preoperative (63.6 ± 2.1) mmHg to postoperative (90.9 ± 1.1) mmHg,and the parameters of heart rates declined from preoperative (106.2 ± 5.9) beats/min to postoperative (94.0 ± 6.2) beats/min,(P ＜ 0.05).Ten patients were available for follow-up of 8-24 months (mean,11.5 months).There were four deaths (29％) postoperatively,among which three were died from multisystem and organ failure,and one from severe brain injury.There were statistically significant differences between the survivors and the deaths in terms of time from injury to operation,average systolic pressures,and average heart rates (P ＜ 0.05).None had complications and wound was well healed.Conclusion For pelvic fractures with hemodynamic instability,extraperitoneal pelvic packing plus temporary occlusion of abdominal aorta has advantages of short manipulation time and effective outcomes,which can control the hemorrhage of pelvic fracture and ameliorate the hemodynamic status.

Objective To evaluate the clinical results of minimally invasive surgery for open tibial plateau fractures using minimally open reduction and Hybrid external fixation.Methods From January 2011 through January 2015,9 complicated open tibial plateau fractures were treated with Hybrid external fixation.They were 6 males and 3 females,with an average age of 33.8 years (range,from 18 to 53 years).According to the Schatzker classification,there were 5 cases of type Ⅴ and 4 ones of type Ⅵ.According to the Gustilo classification,there were 5 cases of type Ⅱ,3 ones of type Ⅲ A and one of type Ⅲ B.All the patients were treated with Hybrid external fixation with or without minimally open reduction.Results The average operation time was 185.6 minutes (from 140 to 240 minutes).The average time for hospital stay was 18.4 days (from 10 to 45 days).The patients were followed up for an average of 15.6 months (from 6 to 36 months).All the 9 fractures got united after an average time of 4.3 months (from 3 to 7 months).The external fixation was removed after confirmation of fracture union.According to Merchant scores,the clinical results were evaluated as excellent in 4 cases,as good in 3,as fair in one and as poor in one.The knee joint was stable in each case.Pin tract infection was observed in one and wire loosening in one.Conclusion Hybrid external fixation with or without minimally open reduction is a safe and feasible surgical method which avoids massive soft tissue dissection for complicated open tibial plateau fractures.

Objective To evaluate the role of phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway in mild head hypothermia-induced reduction of global cerebral ischemiareperfusion (I/R) injury in rats.Methods Sixty male Sprague-Dawley rats,weighing 250-280 g,were randomly divided into 5 groups (n=12 each) using a random number table:sham operation group (group S),group I/R,mild hypothermia + I/R group (group H),mild hypothermia + I/R + solvent control group (group DM),and mild hypothermia + I/R + PI3K inhibitor LY294002 group (group LY).Global cerebral I/R was induced by modified four-vessel occlusion method described by Pulsinelli.In H group,when the hippocampal temperature was decreased to 33℃ using nasopharyngeal cooling,the bilateral common carotid arteries were occluded for 15 min followed by reperfusion,and hippocampal hypothermia was maintained at 32.5-33.5 ℃ for 1 h.In DM and LY groups,DMSO and LY294002 5 μl were injected into the left ventricle,respectively,and 20 min later the other procedures were similar to those previously described in group H.At 8 h of reperfusion,6 rats were sacrificed,and hippocampal specimens were obtained to detect the expression of pFoxO3a,Bcl-2 and Bax (by immuno-histochemistry).The expression of phosphor-Akt (p-Akt) was determined by Western blot.Results Compared with group S,the expression of p-Akt,pFoxO3a and Bcl-2 was significantly up-regulated in I/R,H and DM groups,the expression of Bcl-2 was down-regulated,and the ratio of Bcl-2/Bax was increased in H and DM groups,and the ratio of Bcl-2/Bax was decreased in I/R and LY groups.Compared with group I/R,the expression of p-Akt,pFoxO3a and Bcl-2 was significantly up-regulated,the expression of Bcl-2 was down-regulated,and the ratio of Bcl-2/ Bax was increased in H and DM groups.Compared with H and DM groups,the expression of p-Akt,pFoxO3a and Bcl-2 was down-regulated,the expression of Bax was up-regulated,and the ratio of Bcl-2/ Bax was decreased in group LY.Conclusion PI3K/Akt signaling pathway is involved in reduction of global cerebral I/R injury by mild head hypothermia in rats.

Objective To compare the efficiency of the pelvic packing and the angioembolization for controlling pelvic fracture hemorrhoea.Methods Data of 43 consecutive patients with pelvic fracture hemorrhoea who were enrolled in our hospital from April 2004 to April 2012 were retrospectively analyzed.There were 26 patients who had undergone pelvic packing,including 15 men and 11 women with an average age of 41.6 years (packing group).The causes of the fractures included road accident injury (12 cases),falling injury (8 cases) and the bruise injury caused by heavy object (6 cases).According to the Tile classification,there were 16 cases of type B and 10 cases of type C.There were 4 cases with open pelvic fractures and 5 associated with the abdomen trauma.There were 17 patients who had undergone angioembolization,including 10 men and 7 women,with an average age of 39.2 years (angio group).The causes included road accident injury (9 cases),falling injury (5 cases) and the bruise injury caused by heavy object (3 cases).There were 2 cases of type A,11 cases of type B and 4 cases of type C.The ISS,operation time,blood transfusion and the complication were all recorded respectively.Results For the packing group,the average ISS was 52.4± 15.3,and the operation time was 42.0±2.1 min.The blood transfusion was 15.0±4.7 U before the surgery and 6.0±1.6 U in the first 24 h after the surgery.The mean ICU stay was (8.0±3.6)d.And for the angio group,the average ISS was 40.6±12.4,and the operation time was 86.0±3.6 min.The blood transfusion before the surgery was 13.0±5.4 U vs.10.0±2.1 U in the first 24 h after the surgery,and the ICU stay was 11.0± 1.8 d.2 cases in the packing group underwent repacking and 6 cases in the angio group had received second angioembolization.Five cases died in the packing group but no one died of the hemorrhoea while 4 cases died in the angio group with one died of the hemorrhoea.There were 3 cases in the packing group suffering the deep infection while 1 suffered the superficial infection in the angio group.Conclusion The efficiency of the pelvic packing is higher than the angioembolization because of its shorter operation time and ICU stay,more effective blood control,less blood transfusion after surgery,and lower postoperative mortality.It is very suitable for the application at the local hospital and the national conditions nowadays.

Objective To compare the effect of ISO-C3D navigation and conventional C-arm fluoroscopy in iliosacral screws insertion for treatment of posterior pelvic ring injuries.Methods Sixty-five patients with posterior pelvic ring injuries managed by minimally invasive percutaneous iliosacral screws from June 2006 to January 2012 were reviewed.There were 37 males and 28 females,at age range of 18-63 years (mean 35.9 years).Pelvic fracture classification based on Tile system was type B1 in 10 cases,type B2 in 15,type B3 in nine,type C1 in 18 and type C2 in 13.Patients were divided into ISO-C3D navigation group (Group A,n =35) and C-arm fluoroscopy group (Group B,n =30) according to the difference in intraoperative fluoroscopy methods.Intraoperative fluoroscopy time,time cost in inserting a screw,patient satisfaction rate for bone reduction,bone union time and excellent-good rate of postoperative function were recorded.Results Eighty cannulated screws were inserted for the 65 patients.Average fluoroscopy time and time cost in inserting a screw were shorter in Group A than in Group B (P ＜0.01),but there was no statistical difference between the two gronps in patient satisfaction rate for bone reduction.No patient presented with infection,vascular nerve injury or other complications.Follow-up was 6-24 months (mean 12.7 months) for all the patients.Functional recovery showed no statistical difference between the two groups at postoperative 6 months.All fractures were healed and no delayed union or nonunion happened.Conclusion As compared with conventional C-arm fluoroscopy,computer-navigated surgery can reduce fluoroscopy time and improve screw insertion accuracy.