Objective To explore the electroencephalography(EEG)characteristics of patients with knee osteoarthritis(KOA)which are different from those of healthy subjects during dynamic balance tests,and study the connection and influence between brain activity and KOA.Methods Fifteen patients with KOA and 17 healthy subjects performed the timed up and go test(TUGT)and five times sit-to-stand test(5STS).The EEG characteristics of the 4 frequency bands,namely δ(0.5-4 Hz),θ(4-8 Hz),α(8-14 Hz)and β(14-30 Hz)of 9 electrodes including CZ,C3,C4 in the central region,PZ,P3,P4 in the parietal lobe,and OZ,O1,O2 in the occipital lobe of the cerebral cortex of the subjects were recorded.Time and frequency domain analysis were conducted.Results During 5STS,the time-domain amplitudes of electrodes C4,P3,and P4 in the δ band,electrodes C4,P3,and P4 in the θ band,and electrodes P3 and P4 in the β band of KOA patients were significantly higher than those of healthy subjects(P<0.05);the power of EEG signals of electrodes P3,P4,and O2 in the β band was significantly higher than that of healthy subjects.During TUGT,except that the time-domain amplitude of electrode PZ in the θ band of KOA patients was significantly lower than that of healthy subjects(P<0.05),there was no significant difference in all electrodes in other frequency bands;the power of EEG signals of electrodes C3,CZ,C4,PZ,P4,O1,OZ,O2 in the δ band and electrodes CZ,P3,PZ,and OZ in the α band and electrodes CZ,P4,OZ,and O2 in the β band was significantly lower than that of healthy subjects(P<0.05).Conclusions Compared with healthy subjects,the activity in the parietal lobe area of the brain of KOA patients during 5STS was stronger,while the brain activity in the central region,parietal lobe,and occipital lobe areas of KOA patients during TUGT was weaker than that of healthy subjects.This study may provide some references for clinicians in the prevention and treatment of KOA.

Objective To explore the electroencephalography(EEG)characteristics of patients with knee osteoarthritis(KOA)which are different from those of healthy subjects during dynamic balance tests,and study the connection and influence between brain activity and KOA.Methods Fifteen patients with KOA and 17 healthy subjects performed the timed up and go test(TUGT)and five times sit-to-stand test(5STS).The EEG characteristics of the 4 frequency bands,namely δ(0.5-4 Hz),θ(4-8 Hz),α(8-14 Hz)and β(14-30 Hz)of 9 electrodes including CZ,C3,C4 in the central region,PZ,P3,P4 in the parietal lobe,and OZ,O1,O2 in the occipital lobe of the cerebral cortex of the subjects were recorded.Time and frequency domain analysis were conducted.Results During 5STS,the time-domain amplitudes of electrodes C4,P3,and P4 in the δ band,electrodes C4,P3,and P4 in the θ band,and electrodes P3 and P4 in the β band of KOA patients were significantly higher than those of healthy subjects(P<0.05);the power of EEG signals of electrodes P3,P4,and O2 in the β band was significantly higher than that of healthy subjects.During TUGT,except that the time-domain amplitude of electrode PZ in the θ band of KOA patients was significantly lower than that of healthy subjects(P<0.05),there was no significant difference in all electrodes in other frequency bands;the power of EEG signals of electrodes C3,CZ,C4,PZ,P4,O1,OZ,O2 in the δ band and electrodes CZ,P3,PZ,and OZ in the α band and electrodes CZ,P4,OZ,and O2 in the β band was significantly lower than that of healthy subjects(P<0.05).Conclusions Compared with healthy subjects,the activity in the parietal lobe area of the brain of KOA patients during 5STS was stronger,while the brain activity in the central region,parietal lobe,and occipital lobe areas of KOA patients during TUGT was weaker than that of healthy subjects.This study may provide some references for clinicians in the prevention and treatment of KOA.

Purpose To explore the value of deep learning ultrasound radiomics nomogram in assessing the biological characteristics of invasive metastases in invasive breast cancer.Materials and Methods A retrospective collection of ultrasound imaging data from 180 pathologically confirmed invasive breast cancer between January 2021 to December 2022 in Maoming People's Hospital was conducted,with pathological reports indicating the status of lymph node metastasis(LNM),lymphovascular space invasion(LVSI)or perineural invasion(PNI),according to the LNM/LVSI/PNI status,the three indexes were divided into the training cohort and the verification cohort by 8∶2.Based on Pyradiomics and ResNet50 deep learning extractor,1 316 radiomic features and 2 048 deep learning features were extracted,respectively.The random forest machine learning algorithm was employed to develop evaluation models,and the model scores were calculated.The deep learning radiomics nomograms were developed based on the radiomic and deep learning model scores.The receiver operating characteristic curve was used to assess the performance of the models.The Delong test was applied to analyze the performance differences between different models.Results In the evaluation of LNM,LVSI and PNI status,the area under the curve of all the nomogram in the cohorts demonstrated moderate or above assessment performance(≥0.73),with accuracies all greater than 0.70.Specifically,in the LNM evaluation,the area under the curve of the training cohort was 0.97,the accuracy was 0.93,the sensitivity was 0.88 and the specificity was 0.96.Through the Delong test,the assessment performance of the nomograms was superior to the radiomics models(LNM,Z=2.04,P=0.04;LVSI,Z=2.80,P=0.01;PNI,Z=3.52,P<0.01),and was superior to or similar to the deep learning models(LNM,Z=4.52,P<0.01;LVSI,Z=1.86,P=0.06;PNI,Z=0.31,P=0.76)in the training cohort.Conclusion The deep learning radiomics nomogram can effectively evaluate the biological characteristics of invasion and metastasis in invasive breast cancer.The nomogram improves the assessment performance by integrating the radiomic and deep learning feature information.

Objective To explore proprioceptive changes in patients with knee osteoarthritis(KOA)before and after total knee arthroplasty(TKA).Methods Thirty-four KOA patients were selected as the experimental group and divided into posterior-cruciate-retaining TKA(CR-TKA)and posterior-stabilized TKA(PS-TKA)groups according to the surgical method and followed up for three months after the surgery.Twenty healthy individuals were included as the control group.The proprioception(position sense,kinesthesia,and force sense)of healthy individuals and KOA patients before and after surgery was assessed using the Biodex system III isokinetic training system,self-designed force sense test equipment,and surface electromyography test system,and the data were processed and analyzed.Results Compared with healthy individuals,KOA patients had significantly worse position sense at 30°,45°,and 60°,kinesthesia,and semitendinosus force sense in the affected and unaffected knees(P<0.05).Three months after surgery,there were significant differences in the force sense of the affected biceps femoris and contralateral semitendinosus forces in the CR-TKA group compared with healthy individuals(P<0.05).There were no statistically significant differences in deviation for preoperative and 3-month preoperative position sense,kinesthetic sense,and force sense on the affected and contralateral knee joints between the CR-TKA and PS-TKA groups(P>0.05).Conclusions Knee proprioception in KOA patients was significantly impaired compared with that in healthy individuals.No significant improvement in proprioception was found three months after TKA in the CR-TKA and PS-TKA groups.There was no difference in proprioception among the different surgical methods.The results can provide data support for clinical diagnosis and treatment,as well as determine a direction for subsequent rehabilitation programs.

Objective To explore the proprioception characteristics of knee joints for knee osteoarthritis (KOA) patients before unicondylar knee arthroplasty (UKA) and total knee arthroplasty (TKA). Methods Twenty-nine single-compartment KOA patients were selected. Fifteen patients were treated with UKA (UKA group) and fourteen patients were treated with TKA (TKA group). The test was performed 1 to 3 days before the operation.The keen society scores (KSS) of KOA patients in UKA group and TKA group were compared, and their joint position sense and kinesthesia were compared with control group. Results Significant differences in KSS were found in TKA group and UKA group, and the knee joint position sense and kinesthesia showed no significant differences between TKA group and UKA group.There were no significant differences in the knee joint position sense and kinesthesia between the operated leg and unoperated leg in TKA group and UKA group, and between the left leg and right leg in control group. Compared with control group, there were significant differences between UKA group and TKA group in 60° position sense of the operated leg and unoperated leg.The kinesthesia of the operated leg and unoperated leg in UKA group and TKA group were also significantly different from that in control group. Conclusions Compared with control group, the proprioception of the knee joint in KOA patients was significantly reduced before the surgery, but the characteristics of proprioception in UKA group and TKA group were similar.

Objective To explore the characteristics of short-term static balance of obese children by comparing the excursion of center of pressure (COP) in obese and non-obese children under six kinds of standing circumstances. Methods By using the Footscan balance plate system, parameters of COP excursion for 47 obese children and 50 non-obese children standing on both feet or single foot with eyes open or eyes closed for 10 seconds were obtained, respectively. Results The maximum COP displacement in anterior-posterior direction of obese children was significantly greater than that of non-obese children during standing on both feet with eyes closed. During standing on left foot with eyes open, the sway velocity of obese boys was significantly lower than that of non-obese boys; the maximum COP displacement in medial-lateral direction of obese boys was significantly lower than that of non-obese boys and the maximum displacement of COP in medial-lateral direction of obese girls was significantly greater than that of non-obese girls. The sway velocity of boys was significantly greater than that of girls during standing on left foot with eyes closed. Conclusions In short period of time, the static balance of obese children in anterior-posterior direction was worse than that of non-obese children during standing on both feet with eyes closed. Obesity had different impacts on static balance of different genders. The performance of static balance for obese boys was better than that of non-obese boys, while the performance of static balance for obese girls was worse than that of non-obese girls during standing on left foot with eyes open. Girls had a better static balance performance than boys during standing on left foot with eyes closed. There were no significant differences in static balance performance between boys and girls under the other circumstances. As static balance of children is affected by obesity and gender, it is suggested that different methods of losing weight should be considered for obese children of different genders.

OBJECTIVE：To establish a m ethod for simultaneous determination of neoastilbin ，astilbin，neoisoastilbin，isoastilbin， quercitrin and engeletin in Engelhardia roxburghiana，and conduct multivariate statistical analysis. METHODS ：HPLC-QAMS method was adopted. The determination was performed on Phenomenex SuperLu C 18 column with mobile phase consisted of acetonitrile-0.1％ formic acid （19 ∶ 81，V/V）at the flow rate of 1.0 mL/min. The detection wavelengths were set at 254 nm （neoastilbin，astilbin，neoisoastilbin，isoastilbin，engeletin）and 291 nm（quercitrin）. The column temperature was 30 ℃，and sample size was 10 μL. Using astilbin as internal substance，and the relative correction factors of other 5 factors were calculated. The contents of each component were calculated according to relative correction factor ，and were compared with the results of external standard method. SPSS 22.0 software was used for cluster analysis and principal component analysis. RESULTS ：The linear range of neoastilbin ，astilbin，neoisoastilbin，isoastilbin，quercitrin and engeletin were 0.007-0.311，0.871-18.184，0.002-0.119， 0.052-1.251，0.105-2.202，0.020-2.319 μg（r＞0.999），respectively. RSDs of precision ，reproducibility and stability （24 h）tests were all lower than 3％. The average recoveries were 97.32％，94.89％，97.15％，96.90％，97.52％ and 97.53％（RSDs were 1.09％ -2.60％ ，n＝6），respectively. The relative correction factors of neoastilbin ，neoisoastilbin，isoastilbin，quercitrin and engeletin were 1.252 6，1.198 3，0.958 6，0.807 1 and 1.138 1， respectively. The contents of neoastilbin ， neoisoastilbin， qq.com isoastilbin，quercitrin and engeletin measured by QAMS were 0.394 2-2.067 2，0.139 1-0.804 7，2.864 8-8.554 8，4.581 2- 11.371 1，1.028 9-13.401 5 mg/g；the contents of neoastilbin ， astilbin，neoisoastilbin，isoastilbin，quercitrin and engeletin were 0.367 2-1.925 3，46.361 1-126.342 1，0.138 1-0.798 8，2.966 2-8.857 8， 4.642 5-11.523 3，0.970 6-12.641 9 mg/g，respectively. Relative errors of two methods was lower than or equal to 3.55％. The results of cluster analysis showed that 9 batches of samples could be clustered into two categories ；S8 sample was one category and others were one category. The results of principal component analysis showed that accumulative contribution rate of former 2 principle components was 84.745％，and the results of sample classification were consistent with those of cluster analysis. CONCLUSIONS ： The established HPLC-QAMS method is accurate ，feasible and repeatable ，and can be used for simultaneous determination of 6 flavonoids in E. roxburghiana ，and it can provide reference for quality control.

Objective To compare and analyze the lower limb muscle activity and knee joint force during the stance periods of gait cycle in patients with osteoarthritis before and after total knee arthroplasty (TKA). Methods Based on the OpenSim platform, lower extremity musculoskeletal models of one healthy subject and three patients with osteoarthritis before and after TKA were established. A three-dimensional （3D） motion capture system and a force platform were used to collect the lower limb kinematic data and the ground reaction force during walking, which were used as input parameters to simulate the lower limb muscle activation and knee joint forces. Results The results from the musculoskeletal model were consistent with the results by inverse dynamics based on the 3D motion capture system. The patient's rectus femoris was activated in the loading response and mid stance phases, which was different from that of healthy subject. The activation timing and amplitude of the quadriceps muscle in 3 patients were significantly different before and after TKA. The peak joint forces of 3 patients before TKA were 2.95, 3.15 and 3.43 times of body weight (BW) with the constant load of more than 2 times of BW during stand phase. The peak joint force after TKA were 2.09, 2.48 and 3.96 times of BW respectively. The joint force was not improved and the knee function did not reach the normal level six months after TKA. Conclusions The results of the established musculoskeletal model have certain reliability, and this model can provide a biomechanical auxiliary method for TKA surgery in the future.

Objective To analyze kinematic characteristics of children with spastic cerebral palsy during walking based on the method of gait analysis. Methods The gait of 14 children with spastic cerebral palsy and 16 healthy children, who were required to walk back and forth on level ground at normal speed, was tested using portable gait analyzer. The gait differences between diseased side and healthy side of lower limbs for children with spastic cerebral palsy, as well as the gait differences between children with spastic cerebral palsy children and healthy children were compared. Results For children with spastic cerebral palsy, single step time, swing time and toe-off time of diseased side were significantly longer than those of healthy side (P＜0.05), while step frequency, velocity and terminal stance were significantly shorter than those of healthy side (P＜0.05). Compared with healthy children, gait cycle time, single step time, stance time, swing time, percentage of stance phase, mid stance phase, pre-swing stage and toe-off time for diseased side of children with spastic cerebral palsy were significantly longer (P＜0.05). Stride, velocity, step frequency and terminal stance of the children with spastic cerebral palsy were significantly lower than those of healthy children (P＜0.05). Pulling acceleration for children with spastic cerebral palsy also decreased compared with healthy children (P=0.05). Conclusions The stability of children with spastic cerebral palsy decreased during walking, and their single step time, swing time, toe-off time and pulling acceleration might be considered as the sensitive indicators.

BACKGROUND:Children usually wear school bags when walking, and overweight school bags do harm to the lower extremity and foot, thus affecting the child development. OBJECTIVE:To investigate the effect of obesity on gait characteristics of children wearing school bags during walking. METHODS:Forty pupils were enrolled in accordance with body mass index and China school-age children and adolescents overweight, obesity screening body mass index classification standard, including 20 obese children (body mass index: (28.13±3.4) kg/m2) and 20 non-obese ones (body mass index: (17.44±1.57) kg/m2). The gait parameters of children wearing school bags during walking were measured using a 2-m Footscan Plantar Pressure Plate System from RSscan International. RESULTS AND CONCLUSION: Compared with the non-obese children, the peak pressures under the metatarsal heads II-V, midfoot and heel lateral were significantly higher in obese children wearing school bags during walking (P < 0.05). The time to peak pressures under the toes II-V, the metatarsal heads IV, V and midfoot was also significantly higher (P < 0.05). In addition, the arch index for the foot, and right foot axis angle were significantly larger in the obese children as compared with the non-obese children (P < 0.05). To conclude, obese children wearing school bags during walking have weaker walking stability with flatter foot pattern, the larger foot axis angle and dynamic plantar pressure distribution changes compared with non-obese children, which can result in foot damage.