Objective:To investigate the utility of 68Ga-fibroblast activation protein (FAP) inhibitor (FAPI)-04 PET imaging in assessing the therapeutic response in pressure overload-induced heart failure. Methods:Rat models of pressure overload-induced heart failure were established by abdominal aortic constriction (AAC). Thirty rats were categorized into AAC group, 7 days reverse AAC (rAAC) group, and sham operation (sham) group ( n=10 per group) using completely random grouping method. All rats underwent 68Ga-FAPI-04 PET/CT imaging at 4 and 8 weeks after the ACC operation, while echocardiography, pathological examination, and immunohistochemical analysis were performed at 8 weeks postoperation. One-way analysis of variance, independent-sample t test and Pearson correlation analysis were used for data analysis. Results:68Ga-FAPI-04 PET/CT imaging showed that the target-to-background ratios of the heart and liver had significant differences among three groups both at 4 and 8 weeks postoperation ( F values: 2 547.12, 2 041.71, 462.65, 1 210.97, all P<0.001). Echocardiography revealed left ventricular ejection fraction (LVEF), left ventricular internal diameter at end-diastole (LVIDd), and left ventricular internal diameter at end-systole (LVIDs) in three groups at 8 weeks postoperation were significantly different ( F values: 118.92, 9.11, 10.63, all P<0.01). Rats were sacrificed at 8 weeks postoperation, and Masson staining showed that the fibrosis in the heart and liver of the rAAC group was significantly improved compared with that of the AAC group, and immunohistochemical analysis revealed significantly lower FAP levels in the heart and liver of the rAAC group compared with those of the AAC group ( t values: from -11.27 to -4.16, all P<0.01). FAPI uptake in the heart of the AAC group and rAAC group at 8 weeks postoperation were significantly positively correlated with FAPI uptake in the liver, LVIDd and LVIDs, FAPI uptake in the heart was significantly negatively correlated with LVEF, and FAPI uptake in the heart and liver were significantly positively correlated with fibrosis degree and FAP levels of corresponding organs ( r values: -0.89, -0.88, 0.72-0.97, all P<0.05). Conclusions:68Ga-FAPI-04 PET/CT can show the improvement process of cardio-liver fibrosis following the unloading of excessive pressure in heart failure. Myocardial FAPI uptake is closely related to the extent of heart failure improvement.

Brain-computer interface (BCI) technology enable humans to interact with external devices by decoding their brain signals. Despite it has made some significant breakthroughs in recent years, there are still many obstacles in its applications and extensions. The current used BCI control signals are generally derived from the brain areas involved in primary sensory- or motor-related processing. However, these signals only reflect a limited range of limb movement intention. Therefore, additional sources of brain signals for controlling BCI systems need to be explored. Brain signals derived from the cognitive brain areas are more intuitive and effective. These signals can be used for expand the brain signal sources as a new approach. This paper reviewed the research status of cognitive BCI based on the single brain area and multiple hybrid brain areas, and summarized its applications in the rehabilitation medicine. It's believed that cognitive BCI technologies would become a possible breakthrough for future BCI rehabilitation applications.

In order to stimulate the patients' active participation in the process of robot-assisted rehabilitation training of stroke patients, the rehabilitation robots should provide assistant torque to patients according to their rehabilitation needs. This paper proposed an assist-as-needed control strategy for wrist rehabilitation robots. Firstly, the ability evaluation rules were formulated and the patient's ability was evaluated according to the rules. Then the controller was designed. Based on the evaluation results, the controller can calculate the assistant torque needed by the patient to complete the rehabilitation training task and send commands to motor. Finally, the motor is controlled to output the commanded value, which assists the patient to complete the rehabilitation training task. The control strategy was implemented to the wrist function rehabilitation robot, which could achieve the training effect of assist-as-needed and could avoid the surge of assistance torque. In addition, therapists can adjust multiple parameters in the ability evaluation rules online to customize the difficulty of tasks for patients with different rehabilitation status. The method proposed in this paper does not rely on the information from force sensor, which reduces development costs and is easy to implement.