In the present investigation, we studied four methods of blind source separation/independent component analysis (BSS/ICA), AMUSE, SOBI, JADE, and FastICA. We did the feature extraction of electroencephalogram (EEG) signals of brain computer interface (BCI) for classifying spontaneous mental activities, which contained four mental tasks including imagination of left hand, right hand, foot and tongue movement. Different methods of extract physiological components were studied and achieved good performance. Then, three combined methods of SOBI and FastICA for extraction of EEG features of motor imagery were proposed. The results showed that combining of SOBI and ICA could not only reduce various artifacts and noise but also localize useful source and improve accuracy of BCI. It would improve further study of physiological mechanisms of motor imagery.
ObjectiveTo evaluate the effectiveness of semitendinous and gracilis transfer for the treatment of medial collateral ligament (MCL) injury caused by total knee arthroplasty (TKA). MethodsBetween March 2009 and May 2014, 11 patients (11 knees) with MCL injuries caused by primary TKA were treated by semitendinous and gracilis transfer in primary TKA (injury group). Another 18 patients (21 knees) without MCL injury were included as the control group. There was no significant difference in gender, age, injury sides, disease duration, body mass index, knee varus deformity, and preoperative Knee Society Score (KSS) between 2 groups (P>0.05), with comparability. KSS score was used to evaluate the function after operation. ResultsPrimary healing of incision was obtained in all patients, and no complications of joint instability and pain occurred. The follow-up time was 6-29 months in injury group and was 7-34 months in control group. At last follow-up, the KSS clinical score and functional score were significantly increased to 89.82±3.76 and 89.54±3.50 in the injury group (P<0.05) and were significantly increased to 90.19±3.39 and 90.00±3.53 in the control group (P<0.05) respectively, but no significant difference was shown between 2 groups (t=0.158, P=0.877; t=0.820, P=0.432). X-ray films showed no prosthetic loosening or subsidence during follow-up. ConclusionThe semitendinous and gracilis transfer is reliable for the treatment of MCL injury caused by TKA. The insertions of semitendinous tendon and gracilis are close to that of the knee MCL, which can effectively improve knee function.
ObjectiveTo investigate the effect of medial 1/3 anatomical orientation of the tibial tubercle on the rotational alignment of Gemini MK-Ⅱ tibial components in total knee arthroplasty (TKA). MethodsBetween March 2011 and December 2012, 61 cases (67 knees) of varus knee osteoarthritis underwent Gemini MK-Ⅱ knee arthroplasty, and the clinical data were retrospectively analyzed. There were 12 males and 49 females, with an average age of 67.6 years (range, 50-82 years). The body mass index ranged from 20.9 to 33.7 kg/m2 (mean, 28.2 kg/m2). Unilateral TKA was performed in 55 cases and bilateral TKA in 6 cases. The duration of knee osteoarthritis ranged from 2 to 30 years (mean, 12.1 years). According to radiographic changes, 56 knees were rated as Kellgren-Lawrence grade Ⅲ and 11 knees as grade IV. During TKA, the tibial rotational alignment was determined by medial 1/3 anatomical orientation of the tibial tubercle. The anteroposterior and lateral X-ray films and CT scan were taken to measure the tibial rotational angle (TRA) at pre-and post-operation and to analyze the relative factors for TRA by Pearson correlation analysis. ResultsAll the patients were followed up 18-41 months (mean, 20.5 months). The range of motion (ROM) significantly increased from (98.806±16.969)° preoperatively to (116.806±11.458)° at last follow-up (t=-11.760, P=0.000). The knee society score (KSS) significantly increased from 111.239±20.344 to 160.522±17.872 at last follow-up (t=-27.271, P=0.000). The anatomical tibiofemoral angle (ATFA), posterior condylar angle (PCA), and TRA were all improved after TKA, showing significant differences when compared with preoperative ones (P<0.05). Rotational malalignment was observed in 11 knees (16.42%) before TKA, and in 14 knees (20.90%) at 1 week after TKA, showing no significant difference (χ2=0.443, P=0.506). There were 8 knees (11.94%) of internal rotation (>8°) and 6 knees (8.96%) of external rotation (>8°). The postoperative tibial prosthesis TRA had no correlation with the preoperative ATFA and tibial plateau TRA, the postoperative PCA and ATFA (r=-0.174, P=0.159; r=0.220, P=0.074; r=0.237, P=0.053; r=-0.095, P=0.442). ConclusionIn patients with varus knee osteoarthritis, medial 1/3 anatomical orientation of the tibial tubercle will contribute to the development of tibial rotational malalignment when TKA is performed by using Gemini MK-Ⅱ tibial components.
ObjectiveTo investigate the behavioral recovery of spinal cord injury (SCI) rats that received transplantation of NEP1-40 gene-modified neural stem cells. MethodsNeural stem cells (NSCs) were derived from the cortex tissue of rat embryo at the age of 18 days and identified by Nestin immunofluorescence. The lentiviruses were transduced to NSCs to construct NEP1-40 gene modified NSCs. Spinal cords of 30 Sprague-Dawley rats were hemisected at the nineth thoracic vertebrae level. The rats were randomly assigned to three groups. Cell culture medium, NSCs and NEP1-40 gene-modified NSCs were transplanted into the lesion site of rats of SCI group, NSCs group and NEP1-40-NSCs group respectively 7 days after injury. Additional 10 rats served as blank control group (sham group), which only received laminectomy. Following transplantation, behavior tests including Basso, Beattie, Bresnahan (BBB) Locomotor Rating Scale and grid test were utilized to evaluate spinal cord functional recovery. ResultsBehavior tests 8 weeks after cells transplantation showed that the rats in SCI group got worst results, the BBB scores improved and the grid drop times reduced significantly in NSCs transplantation group (P<0.01) and behavioral test outcomes were best in the NEP1-40 gene-modified NSCs group (P<0.01). ConclusionNEP1-40 gene modification can significantly improve the behavioral recovery of SCI rats that received transplantation of pure neural stem cells. It can provide a new idea and reliable experimental base for the study of NSCs transplantation for spinal cord injury.
Based on force sensing resistor(FSR) sensor, we designed insoles for pressure measurement, which were stable and reliable with a simple structure, and easy to wear and to do outdoor experiments with. So the insoles could be used for gait detection system. The hardware includes plantar pressure sensor array, signal conditioning unit and main circuit unit. The software has the function of data acquisition, signal processing, feature extraction and classification function. We collected 27 groups of gait data of a healthy person based on this system to analyze the data and study pressure distribution under various gait features, i.e. walking on the flat ground, uphill, downhill, up the stairs, and down the stairs. These five gait patterns for pattern recognition and classification by K-nearest neighbors (KNN) recognition algorithm reached up to 90% accuracy. This preliminarily verified the usefulness of the system.
The cognitive impairment of type 2 diabetes patients caused by long-term metabolic disorders has been the current focus of attention. In order to find the related electroencephalogram (EEG) characteristics to the mild cognitive impairment (MCI) of diabetes patients, this study analyses the EEG synchronization with the method of multi-channel synchronization analysis--S estimator based on phase synchronization. The results showed that the S estimator values in each frequency band of diabetes patients with MCI were almost lower than that of control group. Especially, the S estimator values decreased significantly in the delta and alpha band, which indicated the EEG synchronization decrease. The MoCA scores and S value had a significant positive correlation in alpha band.
ObjectiveTo analyze the causes of meniscal root tears (MRTs), and to review the progress in its diagnosis and therapy. MethodsThe published literature about MRTs was extensively reviewed and summarized. ResultsMRTs can be divided into acute traumatic injuries and chronic degenerative injuries; MRI examination is an effective way to diagnose according to meniscal extrusion, ghost sign, and meniscal root linear defects. Conservative treatments are mainly performed for chronic MRTs; partial meniscectomy can obtain predictable improvement in symptoms. Acute MRTs can be treated by arthroscopic meniscus repair and reconstruction which can effectively restore meniscal root anatomy and function, and knee joint degeneration can be postponed. ConclusionMRTs diagnosis relies on MRI, appropriate treatment plan should be made based on the specific circumstances of the patient after accurate diagnosis. Usually the satisfied short-term clinical results can be obtained, while the long-term results need more clinical evaluation.
ObjectiveTo investigate the efficiency of total knee arthroplasty (TKA) for varus osteoarthritic knees with tibial bone resection determined by lateral tibiofemoral joint 90° flexional gap measurement. MethodsBetween March and June 2013, 60 patients (60 knees) with varus osteoarthritic knees underwent TKA. All patients were randomly divided into traditional osteotomy group (control group, 30 cases) and lateral tibiofemoral joint 90° flexional gap measurement resection group (trial group, 30 cases). There was no significant difference in gender, age, affected side, body mass index and preoperative knee society score (KSS), range of motion (ROM) of the knee, anatomic tibiofemoral angle (ATFA), patellar tilt angle, posterior condylar offset (PCO), and joint line height between 2 groups (P>0.05). The bone resection thickness of the distal femoral lateral condyle, femoral posterior lateral condyle, and lateral tibial plateau were measured; and the X-ray films were taken to measure and compare ATFA, patellar tilt angle, PCO, and joint line height after TKA. The knee function recovery was evaluated with KSS score and ROM of the knee. ResultsThe bone resection thickness of the lateral tibial plateau and distal femoral lateral condyle in trial group was significantly smaller than that in control group (P<0.05); while the bone resection thickness of the femoral posterior lateral condyle was significantly bigger than that in control group (P<0.05). The 10 mm polyethylene insert was used in 19 cases of the trial group and in 8 cases of the control group, showing significant difference (Z=-4.040, P=0.003). All the patients were followed up 13-16 months (mean, 14.5 months). Radiography at 6 weeks after TKA indicated that the ATFA, patellar tilt angle, and joint line height had no significant difference between 2 groups (P>0.05); the PCO of trial group was significantly lower than that of control group (P<0.05). The KSS score and ROM of the knee at 12 months after operation were significantly improved when compared with preoperative ones in 2 groups (P<0.05), and trial group was significantly better than control group (P<0.05). ConclusionIt was an effective method to determine bone resection thickness using lateral tibiofemoral joint 90° flexional gap measurement in TKA for varus osteoarthritic knees, which can reduce the bone resection thickness of the tibial plateau and distal femoral lateral condyle and restore the joint line and PCO with better early recovery of the knee function.
ObjectiveTo study the possibility of the C17.2 neural stem cells (NSCs) differentiating into neural cells induced by serum-free condition medium of olfactory ensheathing cells (OECs) and to detect the cell viability of the differentiated cells. MethodsOECs were isloated and cultured from the olfactory bulbs of 3-day-old postnatal mouse to prepare serum-free condition medium of OECs. After C17.2 NSCs were cultured with H-DMEM/F12 medium containing 15% FBS and the cell fusion reached 80%, the 3rd passage cells were induced by serum-free condition medium of OECs in the experimental group, by H-DMEM/F12 in the control group, and non-induced C17.2 NSCs served as the blank control group. The growth condition of cells was observed with inverted microscope. After 5 days, the immunofluorescence staining[microtubule-associated protein 2 (MAP-2) and β-tubulin-Ⅲ] and Western blot (Nestin, β-tubulin-Ⅲ, and MAP-2) were carried out to identify the neural cells derived from NSCs. The cell viabilities were measured by MTT assay and the quantity of lactate dehydrogenase (LDH) release in the medium. ResultsIn the experimental group, the C17.2 NSCs bodies began to contract at 24 hours after induction, and the differentiated cells increased obviously with long synapse at 3 days after induction; in the control group, the cell morphology showed no obvious change at 24 hours, cell body shrinkage, condensation of nuclear chromatin, and lysis were observed at 3 days. The immunofluorescence staining showed that β-tubulin-Ⅲ and MAP-2 of C17.2 NSCs were positive at 5 days after induction, and Western blot suggested that the expression of Nestin protein declined significantly and the expressions of β-tubulin-Ⅲ and MAP-2 protein were increased in the experimental group, showing significant differences when compared with those in the control group and blank control group (P<0.05). The LDH release and the cell viability were 130.60%±6.86% and 62.20%±3.82% in the experimental group, and were 178.20%±5.44% and 18.00%±3.83% in the control group respectively, showing significant differences between 2 groups (P<0.05). The LDH release and the cell viability of experimental group and control group were significantly lower than those of blank control group (100%) (P<0.05). ConclusionNeurotrophic factors from OECs play an important role in inducing C17.2 NSCs differentiation into neural cells and keeping the viability of differentiated cells after induction.
ObjectiveTo evaluate the safety and efficacy of rivaroxaban for prevention of deep vein thrombosis (DVT) in patients with preoperative abnormal D-dimer after total knee arthroplasty (TKA). MethodsBetween August and September 2013,60 consecutive patients with varus knee osteoarthritis undergoing unilateral TKA were enrolled in the study.According to the preoperative D-dimer level,the patients were divided into 2 groups:D-dimer normal group (control group,n=41) and D-dimer abnormal group (test group,n=19).No significant difference was found in gender,age,body mass index,and preoperative knee range of motion between 2 groups (P>0.05).All patients underwent conventional primary TKA and anticoagulation therapy with rivaroxaban to prevent DVT.The tourniquet use time,postoperative hospitalization time,and total hospitalization time were compared between 2 groups.At 1,3,and 5 days after operation,prothrombin time (PT),activated partial thromboplastin time (APTT),thrombin time (TT),fibrinogen (FIB),and D-dimer were measured.Wound complications and DVT were observed. ResultsThe postoperative hospitalization time of the test group was significantly longer than that of the control group (t=2.327,P=0.031),while the tourniquet use time and total hospitalization time showed no significant difference between 2 groups (P>0.05).All the patients were followed up 6-8 months (mean,7.2 months).Wound complications occurred in 3 cases (7.3%) of the control group and in 2 cases (10.5%) of the test group,showing no significant difference (χ2=0.175,P=0.676).Color ultrasonography showed no pulmonary embolism and DVT at 6 weeks after TKA.There were significant differences in PT,TT,and FIB between at pre- and post-TKA in the same group,but no significant difference was found between 2 groups.The APTT and D-dimer had significant differences between at pre- and post-TKA in the same group,and between groups.There was no significant interaction effect between time and group for each index. ConclusionPreoperative abnormal D-dimer level should not be regarded as a contraindication for TKA.The risks of DVT and wound complications in patients with abnormal D-dimer level are similar to patients with normal D-dimer level using rivaroxaban administration after TKA.It is unnecessary to conventional monitor D-dimer and other coagulation and hemorrhage laboratory tests in the patients after TKA.