Extracellular vesicles derived from astrocytes facilitated neurite elongation by activating the Hippo pathway.

Spinal cord injury (SCI) often causes severe neurological dysfunction, and facilitating neurite elongation is particularly important in its treatment. Astrocytes (AS) play an important role in the central nervous system (CNS), and their high plasticity and versatility provide a feasible entry point for relevant research. Our purpose was to explore whether extracellular vesicles (EVs) from astrocytes (AS-EVs) and lipopolysaccharide (LPS)-preactivated astrocytes (LPAS-EVs) facilitate neurite elongation, to explore the underlying mechanism, and to verify whether these EVs promote locomotor recovery in rats. We used LPS to preactivate astrocytes and cocultured them with PC12 cells to observe neurite changes, then extracted and identified AS-EVs and LPAS-EVs and the role and mechanism of these EVs in facilitating neurite elongation was examined in vivo and vitro. We demonstrated that AS-EVs and LPAS-EVs facilitated the elongation of neurites and the recovery of rats with SCI. LPAS-EVs had a stronger effect than AS-EVs, by activating the Hippo pathway, promoting monopole spindle binding protein 1 (MOB1) expression, and reducing Yes-associated protein (YAP) levels. The data also suggest a feedback regulation between MOB1 and p-YAP/YAP. In sum, AS-EVs and LPAS-EVs can play an active role in facilitating neurite elongation by activating the Hippo pathway. These findings provide a new strategy for treating SCI and other CNS-related injuries.

[Influence of preoperative thoracic kyphosis on the sagittal profile of the lumbar spine in idiopathic thoracic scoliosis following selective thoracic fusion].

OBJECTIVE: To analyze the influence of thoracic kyphosis on the sagittal compensatory mode of the spine in idiopathic thoracic scoliosis after the selective thoracic fusion. METHODS: Ninety AIS patients (mean age 14.5 years old) who received selective thoracic fusion from February 1999 to December 2005 in one institution with at least 24-month follow-up were evaluated. Forty-one patients underwent anterior spinal fusion and forty-nine patients underwent posterior spinal fusion. And then the patients were divided into two subgroups according to the magnitude of preoperative thoracic kyphosis (TK): Group A, TK less than 10 degrees ; and Group B, TK more than 10 degrees . The radiological parameters were measured including: thoracic and lumbar curve magnitude, TK, lumbar lordosis (LL), thoracolumbar junction kyphosis (T(10)-L(2), TJK), distal junctional kyphosis (DJK), sagittal vertical axis (SVA). RESULTS: At final follow-up, TK, TJK and DJK increased significantly compared with preoperative Cobb angle in subgroup A patients who underwent anterior spinal fusion (P < 0.05). Generally, there was a lordosis loss of TJK and DJK during follow-up. While in subgroup B, TJK at final follow-up increased apparently compared with preoperative Cobb angle (P < 0.05). And there was a increased trend of DJK in spite of no significant difference, however, there was no obvious change of TK in subgroup B. At the final follow-up, TK and TJK increased significantly in subgroup A patients who underwent posterior spinal fusion (P < 0.05). And there was a increased tendency of DJK during follow-up, although there was no significant difference. And there was no obvious change of TK, TJK and DJK in subgroup B. There was a increased trend of LL in spite of no significant difference in group A patients who underwent anterior or posterior spinal fusion. The sagittal balance maintained well during follow-up in both groups. CONCLUSIONS: For AIS patients with thoracic hypokyphosis, normal TK and LL could be achieved during follow-up with selective thoracic instrumentation. However, the increase of DJK and TJK may occur during the follow-up, and the risk factors may be the anterior short segmental fusion and the reconstruction of the sagittal profile in the hypokyphosis patients.

[Pulmonary dysfunction patterns in patients with Marfan and Marfanoid syndrome associated with scoliosis and the influencing factors].

OBJECTIVE: To investigate the impairment pattern and the influencing factors of pulmonary function in patients with Marfan and Marfanoid syndrome associated scoliosis (MS). METHODS: In this retrospective study, totally 25 MS patients (aged 11 - 20 years, 11 boys and 14 girls) who received posterior instrumentation and fusion (Group A) and 38 adolescent idiopathic scoliosis (AIS) patients (Group B) (aged 10 - 19 years, 11 boys and 27 girls) were included from February 1998 to September 2007. The curve pattern was matched in both groups. The preoperative pulmonary function test (PFTs) were compared in two groups. And the parameters influencing the preoperative pulmonary function were analyzed in group A. RESULTS: In Group A, the Cobb angle of thoracic curve was negatively correlated with the percentage of predicted pulmonary volumes (VC%, FVC% and FEV1%) (r = -0.514, -0.503, -0.464, P < 0.05). And the reduction of lung function parameters (VC%, FVC%, FEV1% and MMEF%) was more severe in Group A than in Group B with compared magnitude of thoracic curve (P < 0.05). In Group A, the extent of impairment of pulmonary function in patients with the number of vertebrae involved ≥ 8 were more severe than those involved < 8 vertebrae (P < 0.05). However, there was no significant difference of deterioration of lung function between the higher apex (T4₋8) subgroup and lower apex (T9₋12) subgroup. And no correlation was found between thoracic kyphosis and the degrees of impairment of respiration function. CONCLUSIONS: Patients with MS have mixed ventilation dysfunction, which is more severe than AIS patients with matched age and Cobb angle. The pulmonary dysfunction in MS patients can be influenced by the severity of thoracic curve and the number of involved vertebrae.

[FBN3 gene polymorphisms in adolescent idiopathic scoliosis patients].

OBJECTIVE: To investigate the association of FBN3 gene polymorphism with abnormal growth pattern in adolescent idiopathic scoliosis (AIS) patients. METHODS: Blood samples were obtained from 273 AIS patients, aged (14.6 +/- 2.1) (10 - 18), and 287 healthy age-matched females adolescents. The anthropometric parameters of the AIS group, including age, body height, weight, arm span, Cobb angle, time of menarche, and Risser's sign were recorded. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to detect the FBN3 gene distribution. RESULTS: The genotype and allele frequency distribution were comparable between the AIS and normal control groups. There was no association with curve severity, arm span, BMI in patients with AIS. In the rs7257948, There were not significant differences in the FBN3 gene polymorphism sites rs35579498, rs12608849, and rs7257948, and allele distribution between these 2 groups. In the AIS group, the patients with GG genotype the number of those whose body height was > or = 160 cm was higher than those whose body height was < 160 cm (P = 0.01). In rs35579498, the frequency of allele T was relatively higher in the AIS patients than in the controls (P = 0.051). In the AIS patients, the expression rate of CT genotype in those whose menarche age was > or = 12 years was significantly higher than those whose menarche was < 12 years (P = 0.042). CONCLUSION: The polymorphisms of the 4 SNPs in the exons of FBN3 gene are neither associated with the occurrence nor the curve severity of AIS. However, in rs35579498, T allele appears to be overrepresented in the patients compared with the controls. Mutation in this site my plays a role in the occurrence and progression of AIS, and in rs7257948, polymorphism of FBN3 gene may be associated with body height of the AIS patients.

[The influence of thoracic kyphosis on sagittal balance of the lumbosacral spine in thoracic idiopathic scoliosis patients].

OBJECTIVES: To evaluate the influence of thoracic kyphosis to sagittal alignment and balance of the lumbosacral vertebrae in thoracic adolescent idiopathic scoliosis patients. METHODS: Standing posteroanterior and lateral x-rays of a cohort of 55 patients with thoracic adolescent idiopathic scoliosis were obtained. The patients were classified according to their thoracic kyphosis, the first group TK < 10 degrees and the second group 10 degrees < or = TK < or = 40 degrees . The following parameters were measured: lumbar lordosis (LL), upper and lower arc of lumbar lordosis, sagittal vertical axis, sacral slope (SS), pelvic incidence (PI), pelvic tilt (PT). Sagittal plane parameters were analyzed using t-test between two groups, with significance set at P < 0.05. Linear correlations between parameters were calculated using Pearson correlation coefficients, with significance set at P < 0.01. RESULTS: There were smaller LL and upper arc of lumbar lordosis in the first group. Significant linear correlations were found between each single adjacent shape parameter. Significant correlations were also found between TK, LL and upper arc of lumbar lordosis, as well as between PT, SS and PI. CONCLUSIONS: Sagittal alignment and balance of the lumbosacral vertebrae may influence the thoracic kyphosis in AIS patients. The mechanism of this influence may through the adaptation of upper arc of lumbar lordosis. This influence must be considered in thoracic adolescent idiopathic scoliosis patients who undergo selective posterior thoracic fusion.

[Hemiarthroplasty for the treatment of complicated femoral intertrochanteric fracture in elderly patients].

OBJECTIVE: To discuss the hemiarthroplasty for the threatment of femoral intertrochanteric fracture in elderly patients. METHODS: From August 2013 to January 2017, 66 elderly patients with complicated femoral intertrochanteric fracture were treated including 20 males and 46 females with an average age of 85 years old ranging from 80 to 95. According to improve Evans classification, 33 cases were type III, 24 cases were type IV, 9 cases were type V. History included 31 cases of hypertension, 10 cases of diabetes, 12 cases of severe osteoporosis, 5 cases of atrial fibrillation, 3 cases of pulmonary heart disease, and 1 case of multiple myeloma. Hip hemiarthroplasty was used in 34 cases and internal fixation in 32 cases. The bleeding volume, complications and Harris scores of the two groups were observed and compared. RESULTS: The amount of blood loss during and after operation were(320±20) ml and(200±25) ml in the joint replacement group, and (350±30) ml and(250±30) ml in the internal fixation group, and there was no statistical difference between the two groups(P>0.05). All patients were followed up for an average of 2 years. The Harris score of the joint replacement group was 85.0±6.4, which was higher than that of the internal fixation group (72.0±3.4)(P<0.05). The difference of complications between the two groups was statistically significant (P<0.05). CONCLUSIONS: The elderly patients with femoral intertrochanteric fractures have many basic diseases, and the expected survival time is short. Using artificial bipolar femoral head prosthesis can restore the hip function early and to the maximum degree, make the patients get down in the bed early, effectively reduce the complications caused by internal fixation, improve the patient's quality of life and satisfaction, and early treatment. It is a kind of supplemental treatment, which conforms to the theory of rapid rehabilitation surgery and injury control, but should not expand the indication and strengthen the management of the perioperative period.

[Preliminary effectiveness of laminated bevel suturing technique for treating acute closed Achilles tendon rupture].

Objective: To introduce a modified technique for treating acute closed Achilles tendon rupture and evaluate the preliminary effectiveness. Methods: Between March 2011 and September 2015, 8 cases (8 sides) with acute closed Achilles tendon rupture were repaired with the laminated bevel suturing technique. All of the patients were male with an average age of 39.3 years (range, 22-58 years), injured in nonprofessional sports. The diagnosis was confirmed by typical signs of positive heel-lift test and Thompson test; the complete rupture of Achilles tendon was determined by color Doppler ultrasound or MRI, and the distance between the stump and calcaneus was 2-5 cm (mean, 3.3 cm). The time from injury to operation was 2-12 days (mean, 4.1 days). With the patient in prone position, a posterior longitudinal incision medial to the tendon was made, the broken stumps of Achilles tendon were divided into 3 layers on the coronal plane, fibers made into strips. The strips were staggered and stacked, stitched side to side with absorbable suture. The ankle joint at the plantar flexion position was fixed with plaster, and early rehabilitation exercise was carried out. Results: The operation time was 70-135 minutes (mean, 99 minutes); the intraoperative blood loss was 5-30 mL (mean, 15.6 mL). All the incisions healed by first intention without infection, except for 1 case who need dressing exchange because of partial delayed healing. All the patients were followed up 6-50 months (mean, 30.5 months). There was no complication of surgical site infection, sural nerve injury, or deep vein thrombosis. The patients could walk normally with powerful raising heels and return to previous sports, without complication of re-rupture. Compared with the contralateral side, the activity of ankle joint dorsiflexion reduced 0-6° (mean, 3°); plantar flexion reduced 1-5° (mean, 2°). At last follow-up, according to Arner-Lindholm score, the surgical results were excellent in 7 cases and good in 1 case, with an excellent and good rate of 100%. Conclusion: Laminated bevel suturing technique is simple for repairing acute closed Achilles tendon rupture without the need of special surgical instruments. It provides enough tensile strength for early rehabilitation exercise to rapid and good recovery.

CaSR and calpain contribute to the ischemia reperfusion injury of spinal cord.

Spinal cord ischemia reperfusion injury (SCIRI) can cause spinal cord dysfunction and even devastating paraplegia. Calcium-sensing receptor (CaSR) and calpain are two calcium related molecules which have been reported to be involved in the ischemia reperfusion injury of cardiomyocytes and the subsequent apoptosis. Here, we studied the expression of CaSR and calpain in spinal cord neurons and tissues, followed by the further investigation of the role of CaSR/calpain axis in the cellular apoptosis process during SCIRI. The results of in vitro and in vivo studies showed that the expression of CaSR and calpain in spinal cord neurons increased during SCIRI. Moreover, the CaSR agonist GdCl3 and antagonist NPS-2390 enhanced or decreased the expression of CaSR and calpain respectively. The expressions of CaSR and calpain were also consistent with the cellular apoptosis in spinal cord. Taken together, CaSR-calpain contributes to the SCIRI apoptosis, and CaSR antagonist might be a helpful drug for alleviating SCIRI.

[effectiveness of open reduction and internal fixation without opening joint capsule on tibial plateau fracture].

OBJECTIVE: To introduce the surgery method to reset and fix tibial plateau fracture without opening joint capsule, and evaluate the safety and effectiveness of this method. METHODS: Between July 2011 and July 2013, 51 patients with tibial plateau fracture accorded with the inclusion criteria were included. All of 51 patients, 17 cases underwent open reduction and internal fixation without opening joint capsule in trial group, and 34 cases underwent traditional surgery method in control group. There was no significant difference in gender, age, cause of injury, time from injury to admission, side of injury, and types of fracture between 2 groups (P > 0.05). The operation time, intraoperative blood loss, incision length, incision healing, and fracture healing were compared between 2 groups. The tibial-femoral angle and collapse of joint surface were measured on X-ray film. At last follow-up, joint function was evaluated with Hospital for Special Surgery (HSS) knee function scale. RESULTS: The intraoperative blood loss in trial group was significantly less than that in control group (P < 0.05). The incision length in trial group was significantly shorter than that in control group (P < 0.05). Difference was not significant in operation time and the rate of incision healing between 2 groups (P > 0.05). The patients were followed up 12-30 months (mean, 20.4 months) in trial group and 12-31 months (mean, 18.2 months) in control group. X-ray films indicated that all cases in 2 groups obtained fracture healing; there was no significant difference in the fracture healing time between 2 groups (t=1.382, P=0.173). On X-ray films, difference was not significant in tibial-femoral angle and collapse of joint surface between 2 groups (P > 0.05). HSS score of the knee in trial group was significantly higher than that of control group (t=3.161, P=0.003). CONCLUSION: It can reduce the intraoperative blood loss and shorten the incision length to use open reduction and internal fixation without opening joint capsule for tibial plateau fracture. Traction of joint capsule is helpful in the reduction and good recovery of joint surface collapse. In addition, the surgery without opening joint capsule can avoid joint stiffness and obtain better joint function.