In this work, a total of 322 tests were taken on young volunteers by performing 10 different falls, 6 different Activities of Daily Living (ADL) and 7 Dynamic Gait Index (DGI) tests using a custom-designed Wireless Ga...In this work, a total of 322 tests were taken on young volunteers by performing 10 different falls, 6 different Activities of Daily Living (ADL) and 7 Dynamic Gait Index (DGI) tests using a custom-designed Wireless Gait Analysis Sensor (WGAS). In order to perform automatic fall detection, we used Back Propagation Artificial Neural Network (BP-ANN) and Support Vector Machine (SVM) based on the 6 features extracted from the raw data. The WGAS, which includes a tri-axial accelerometer, 2 gyroscopes, and a MSP430 microcontroller, is worn by the subjects at either T4 (at back) or as a belt-clip in front of the waist during the various tests. The raw data is wirelessly transmitted from the WGAS to a near-by PC for real-time fall classification. The BP ANN is optimized by varying the training, testing and validation data sets and training the network with different learning schemes. SVM is optimized by using three different kernels and selecting the kernel for best classification rate. The overall accuracy of BP ANN is obtained as 98.20% with LM and RPROP training from the T4 data, while from the data taken at the belt, we achieved 98.70% with LM and SCG learning. The overall accuracy using SVM was 98.80% and 98.71% with RBF kernel from the T4 and belt position data, respectively.展开更多
This paper presents a low-power CMOS analog front-end (AFE) IC designed with a selectable on-chip dual AC/DC- coupled paths for bio-sensor applications. The DC-coupled path can be selected to sense a biosignal with us...This paper presents a low-power CMOS analog front-end (AFE) IC designed with a selectable on-chip dual AC/DC- coupled paths for bio-sensor applications. The DC-coupled path can be selected to sense a biosignal with useful DC information, and the AC-coupled path can be selected for sensing the AC content of the biosignal by attenuating the unwanted DC component. The AFE IC includes a DC-coupled instrumentation amplifier (INA), two variable-gain 1st-order low pass filters (LPF) with tunable cut-off frequencies, a fixed gain 2nd-order Sallen-Key high-pass filter (HPF) with tunable cut-off frequencies, a buffer and an 8-bit differential successive approximation register (SAR) ADC. The entire AFE channel is designed and fabricated in a proprietary 0.35-μm CMOS technology. Excluding an external buffer needed to properly drive the ADC, the measured AFE IC consumes only 2.37 μA/channel with an input referred noise of ~40 μVrms in [1 Hz, 1 kHz], and successfully displays proper ECG (electrocardiogram) and electrogram (EGM) waveforms for QRS peaks detection. We expect that the low-power dual-path design of this AFE IC can enable it to periodically record both the AC and the DC signals for proper sensing and calibration for various bio-sensing applications.展开更多
Cell membrane-derived nanoparticles(NPs)have recently gained popularity due to their desirable features in drug delivery such as mimicking properties of native cells,impeding systemic clearance,and altering foreign bo...Cell membrane-derived nanoparticles(NPs)have recently gained popularity due to their desirable features in drug delivery such as mimicking properties of native cells,impeding systemic clearance,and altering foreign body responses.Besides NP technology,adoptive immunotherapy has emerged due to its promise in cancer specificity and therapeutic efficacy.In this research,we developed a biomimetic drug carrier based on chimeric antigen receptor(CAR)transduced T-cell membranes.For that purpose,anti-HER2 CAR-T cells were engineered via lentiviral transduction of anti-HER2 CAR coding lentiviral plasmids.Anti-HER2 CAR-T cells were characterized by their specific activities against the HER2 antigen and used for cell membrane extraction.Anti-cancer drug Cisplatin-loaded poly(D,L-lactide-co-glycolic acid)(PLGA)NPs were coated with anti-human epidermal growth factor receptor 2(HER2)-specific CAR engineered T-cell membranes.Anti-HER2 CAR-T-cell membrane-coated PLGA NPs(CAR-T-MNPs)were characterized and confirmed via fluorescent microscopy and flow cytometry.Membrane-coated NPs showed a sustained drug release over the course of 21 days in physiological conditions.Cisplatin-loaded CAR-T-MNPs also inhibited the growth of multiple HER2+cancer cells in vitro.In addition,in vitro uptake studies revealed that CAR-T-MNPs showed an increased uptake by A549 cells.These results were also confirmed via in vivo biodistribution and therapeutic studies using a subcutaneous lung cancer model in nude mice.CAR-T-MNPs localized preferentially at tumor areas compared to those of other studied groups and consisted of a significant reduction in tumor growth in tumor-bearing mice.In Conclusion,the new CAR modified cell membrane-coated NP drug-delivery platform has demonstrated its efficacy both in vitro and in vivo.Therefore,CAR engineered membrane-coated NP system could be a promising cell-mimicking drug carrier that could improve therapeutic outcomes of lung cancer treatments.展开更多
文摘In this work, a total of 322 tests were taken on young volunteers by performing 10 different falls, 6 different Activities of Daily Living (ADL) and 7 Dynamic Gait Index (DGI) tests using a custom-designed Wireless Gait Analysis Sensor (WGAS). In order to perform automatic fall detection, we used Back Propagation Artificial Neural Network (BP-ANN) and Support Vector Machine (SVM) based on the 6 features extracted from the raw data. The WGAS, which includes a tri-axial accelerometer, 2 gyroscopes, and a MSP430 microcontroller, is worn by the subjects at either T4 (at back) or as a belt-clip in front of the waist during the various tests. The raw data is wirelessly transmitted from the WGAS to a near-by PC for real-time fall classification. The BP ANN is optimized by varying the training, testing and validation data sets and training the network with different learning schemes. SVM is optimized by using three different kernels and selecting the kernel for best classification rate. The overall accuracy of BP ANN is obtained as 98.20% with LM and RPROP training from the T4 data, while from the data taken at the belt, we achieved 98.70% with LM and SCG learning. The overall accuracy using SVM was 98.80% and 98.71% with RBF kernel from the T4 and belt position data, respectively.
文摘This paper presents a low-power CMOS analog front-end (AFE) IC designed with a selectable on-chip dual AC/DC- coupled paths for bio-sensor applications. The DC-coupled path can be selected to sense a biosignal with useful DC information, and the AC-coupled path can be selected for sensing the AC content of the biosignal by attenuating the unwanted DC component. The AFE IC includes a DC-coupled instrumentation amplifier (INA), two variable-gain 1st-order low pass filters (LPF) with tunable cut-off frequencies, a fixed gain 2nd-order Sallen-Key high-pass filter (HPF) with tunable cut-off frequencies, a buffer and an 8-bit differential successive approximation register (SAR) ADC. The entire AFE channel is designed and fabricated in a proprietary 0.35-μm CMOS technology. Excluding an external buffer needed to properly drive the ADC, the measured AFE IC consumes only 2.37 μA/channel with an input referred noise of ~40 μVrms in [1 Hz, 1 kHz], and successfully displays proper ECG (electrocardiogram) and electrogram (EGM) waveforms for QRS peaks detection. We expect that the low-power dual-path design of this AFE IC can enable it to periodically record both the AC and the DC signals for proper sensing and calibration for various bio-sensing applications.
基金supported by the Cancer Prevention&Research Institute of Texas(CPRIT)High-Impact/High-Risk Research Awards#RP210206.
文摘Cell membrane-derived nanoparticles(NPs)have recently gained popularity due to their desirable features in drug delivery such as mimicking properties of native cells,impeding systemic clearance,and altering foreign body responses.Besides NP technology,adoptive immunotherapy has emerged due to its promise in cancer specificity and therapeutic efficacy.In this research,we developed a biomimetic drug carrier based on chimeric antigen receptor(CAR)transduced T-cell membranes.For that purpose,anti-HER2 CAR-T cells were engineered via lentiviral transduction of anti-HER2 CAR coding lentiviral plasmids.Anti-HER2 CAR-T cells were characterized by their specific activities against the HER2 antigen and used for cell membrane extraction.Anti-cancer drug Cisplatin-loaded poly(D,L-lactide-co-glycolic acid)(PLGA)NPs were coated with anti-human epidermal growth factor receptor 2(HER2)-specific CAR engineered T-cell membranes.Anti-HER2 CAR-T-cell membrane-coated PLGA NPs(CAR-T-MNPs)were characterized and confirmed via fluorescent microscopy and flow cytometry.Membrane-coated NPs showed a sustained drug release over the course of 21 days in physiological conditions.Cisplatin-loaded CAR-T-MNPs also inhibited the growth of multiple HER2+cancer cells in vitro.In addition,in vitro uptake studies revealed that CAR-T-MNPs showed an increased uptake by A549 cells.These results were also confirmed via in vivo biodistribution and therapeutic studies using a subcutaneous lung cancer model in nude mice.CAR-T-MNPs localized preferentially at tumor areas compared to those of other studied groups and consisted of a significant reduction in tumor growth in tumor-bearing mice.In Conclusion,the new CAR modified cell membrane-coated NP drug-delivery platform has demonstrated its efficacy both in vitro and in vivo.Therefore,CAR engineered membrane-coated NP system could be a promising cell-mimicking drug carrier that could improve therapeutic outcomes of lung cancer treatments.