A non-coated enzyme-linked immunosorbent assay for screening zika virus envelope protein / 南方医科大学学报

OBJECTIVE@#To establish a non-coated enzyme-linked immunosorbent assay (ELISA) based on zika virus envelope (E) protein for detecting the expression of E protein in infected cells.@*METHODS@#Adherent Vero-143 cells infected with zika virus in a 96-well plate were fixed, and the antibodies against zika virus E protein were added at an optimized concentration to establish the non-coated ELISA method for E protein. The antiviral activities of lignans compound C1 was evaluated using this method. The accuracy of this non-coated ELISA was verified by RT-PCR, and the cross reaction with dengue virus was assessed.@*RESULTS@#After optimization, the background absorbance at 450 nm of uninfected cells was reduced to about 0.20. The antiviral activities of lignans compound C1 detected by this method were basically consistent with the results of RT-PCR. No cross reaction with dengue virus was found in this assay.@*CONCLUSIONS@#A non- coated ELISA method based on zika virus E protein was established, which can be used for screening antiviral agents against zika virus.

Radiofrequency combined with platelet-rich plasma for repair of white meniscal tears / 中国组织工程研究

BACKGROUND: Both biological and physical methods contribute to the repair of white meniscal tears, so the combined use will be better. OBJECTIVE: To study the influence of radiofrequency combined with platelet-rich plasma (PRP) on the repair of white meniscal tears. METHODS: Forty-eight adult New Zealand white rabbits were randomly divided into four groups, including simple suture, radiofrequency, PRP, and combination groups, and then the model of medial meniscus posterior root tears was established in all experimental animals. The simple suture group underwent interrupted mattress suture; the radiofrequency group was treated with radiofrequency (20 W, 45 ℃) after suture; the PRP group received the intra-articular injection of PRP after suture; the combination group was firstly treated with radiofrequency after suture, and then underwent the intra-articular injection of PRP. The gross and histological changes of the meniscus were observed, and the expression levels of transforming growth factor β1, vascular endothelial growth factor and platelet-derived growth factor were detected at 3 and 12 weeks postoperatively. RESULTS AND CONCLUSION: At 12 weeks after operation, the simple suture group showed no healing; the radiofrequency and PRP groups healed partially; and the combination group healed completely, and chondrocytes and collagen fibers arranged regularly. There was a significant difference in the healing rate between combination and simple suture groups (P=0.003). At 3 weeks postoperatively, the expression levels of vascular endothelial growth factor in the radiofrequency, PRP and combination groups were obviously higher than that in the simple suture group, which decreased markedly at the 12th week. At 3 weeks postoperatively, the expression level of platelet-derived growth factor was increased in all groups, especially in the PRP and combination groups. The PRP group showed the highest level of transforming growth factor β1 at 12 weeks postoperatively. These results manifest that the combination of radiofrequency and PRP promotes the repair of white meniscal tears by increasing the cell proliferation, cell mitosis and angiogenesis.

Sequential damage of posterior ligamentous complex and its clinical significance in patients with thoracolumbar fracture / 中华创伤杂志

Objective To investigate the damage sequence of posterior ligamentous complex (PLC) and its clinical significance in thoracolumbar fracture.Methods Data of 132 patients with spinal fracture evaluated with X-rays,CT and short-tau inversion-recovery (STIR) sequences in MRI were collected prospectively.Fracture morphology was classified using the AO classification.PLC components including interspinous ligament (ISL),supraspinous ligament (SSL),ligamentum flavum (LF) and facet capsules (FC) were assessed and classified as intact,edema,or tear.ISL edema was further subdivided depending on the extension (＞ 50％ or ≤50％).Correlation between MRI signal and AO progressive scale of morphological damage was analyzed.Results AO type A1/A2 fracture associated with only FC distraction.AO type A3 fracture showed additional ISL tear,usually less than 50％,with neither LF nor SSL tear.AO type B1 fracture showed FC distraction,ISL edema or disruption,and low rate of SSL/LF tear,but B2 fracture increased the rate of SSL/LF tear.AO type C fracture showed facet fracture or dislocation and ISL,SSL as well as LF tear.High correlation was found between AO progressive scale and MRI signal (P ＜ 0.01).Conclusions MRI study can well display the PLC damage and damage sequence.MRI correlates with AO progressive scale of morphological damage,which shows a progressive orderly rupture sequence among different PLC components as traumatic forces increase.

Influences of fenofibrate on oxidative stress and endoplasmic reticulum stress in livers of hyperlipidemic rats / 实用医学杂志

Objective To study the influences of fenofibrate on oxidative stress and endoplasmic reticulum stress in livers of hyperlipidemic rats. Methods Male SD rats were fed with high-fat diet for 12 weeks to induce a model of hyperlipidemia, then divided into control group, high-fat diet group with another four-week high-fat diet and fenofibrate group, in which rats were treated with fenofibrate [100 mg / (kg·d)] for 4 weeks. Then improvement of insulin resistance was detected in rats with GTT and ITT experiment. The serum levels of glucose (GLU), fasting insulin (FINS),triglyceride (TG) and total cholesterol (TC) were detected. The pathological changes of livers were detected with Oil Red O staining. The oxidative stress indices such as T-SOD, Mn-SOD, GSH and T-AOC were detected with liver homogenate. The expression of GRP78 was detected with real-time quantification RT-PCR and Western blot analysis respectively. Results Compared with rats with high-fat-diet, rats after fenofibrate treatment showed obviously improved insulin resistance, lower serum level of TG, TC and FINS (P 0.05). The expression of GRP78 at mRNA and protein levels were increased significantly after fenofibrate treatment (P < 0.05). Conclusions Fenofibrate has significant effects on improving insulin resistance and lipid regulation, which might be related to decreased oxidative stress and subsequent endoplasmic reticulum stress.

Accuracy evaluation of MRI in detecting posterior ligament complex injury associated with thoracolumbar factures / 中华创伤杂志

Objective To investigate the consistency of M RI detecting posterior ligamentous complex (PLC) injury associated with thoracolumbar factures.Methods MRI data of 170 cases of thoracolumbar fractures were reviewed retrospectively.Each case underwent MRI around one week postinjury.MRI data were analyzed and compared by three physicians respectively to discuss the consistency in MRI detection of PLC injury and the severity of PLC injury.Results Kappa coefficient was 0.846 between observer 1 and 2,0.768 between observer 1 and 3,and 0.793 between observer 2 and 3.Interobserver reliability was high and overall Kappa coefficient was 0.803.Severity of PLC injury was interrelated with spinal cord nerve injury (P ＜ 0.05).Conclusions Accurate detection of PLC injury in thoracolumbar fractures is beneficial to clear the mechanical stability of the spine.MRI detection of PLC injury is of high consistency and hence deserves wide use.

Biomechanical study on bone marrow-derived mesenchymal stem cells promoting tendon-bone healing following anterior cruciate ligament reconstruction / 中华创伤杂志

Objective To observe the effect of bone marrow-derived mesenchymal stem cells (bMSCs) on graft healing within a bone tunnel after anterior cruciate ligament (ACL) reconstruction in rabbits.Methods The study involved 24 New Zealand white rabbits undergone ACL reconstruction with an autologous ipsilateral gastrocnemius tendon graft.Both hindlimbs were included.In one hindlimb,graft coated with fibrin glue compound by bMSCs was employed (bMSCs group).Whereas in the contralateral hindlimb,graft coated with fibrin glue without cells was employed (control group).At postoperative 2,4,6 and 8 weeks,specimens were harvested to have a biomechanical test of tensile strength and stiffness of tendon-bone interface.Results Tensile strength and stiffness of tendon-bone interface in both experiment and control groups presented a rising trend with the prolong of repair time.In contrast,significantly higher tensile strength and stiffness of tendon-bone interface were observed in experiment group since the 6 weeks (P ＜ 0.05).Conclusion bMSCs transplantation significantly enhances the early tensile strength and stiffness at tendon-bone interface after ACL reconstruction in rabbits and improves the graft healing within a bone tunnel.