The requirement for unconstrained monitoring of heartbeat during sleep is increasing, but the current detection devices can not meet the requirements of convenience and accuracy. This study designed an unconstrained ballistocardiogram (BCG) detection system using acceleration sensor and developed a heart rate extraction algorithm. BCG is a directional signal which is stronger and less affected by respiratory movements along spine direction than in other directions. In order to measure the BCG signal along spine direction during sleep, a 3-axis acceleration sensor was fixed on the bed to collect the vibration signals caused by heartbeat. An approximate frequency range was firstly assumed by frequency analysis to the BCG signals and segmental filtering was conducted to the original vibration signals within the frequency range. Secondly, to identify the true BCG waveform, the accurate frequency band was obtained by comparison with the theoretical waveform. The J waves were detected by BCG energy waveform and an adaptive threshold method was proposed to extract heart rates by using the information of both amplitude and period. The accuracy and robustness of the BCG detection system proposed and the algorithm developed in this study were confirmed by comparison with electrocardiogram (ECG). The test results of 30 subjects showed a high average accuracy of 99.21% to demonstrate the feasibility of the unconstrained BCG detection method based on vibration acceleration.
The transforming growth factor-β1 (TGF-β1)/Smad3 signal pathway is related to mutiple physiological and pathological generation mechanism of human being. Up to date, however, the spacial and time information on the phosphorylated Smad3 is still unclear. In this study, the process of Smad3 phosphorylation was observed under the physiological state in the living cells. Firstly, the ECFP-Smad3-Citrine (Smad3 biosensor) fusion protein expression vector was constructed and identified. Then the Smad3 biosensor was transfected into 293T cells. The transfection efficiency and the expressions of fusion proteins were observed in 24 hours. Thirdly, Smad3 biosensor flurorescence resonance energy transfer (FRET) was observed with the inversion fluorescence microscope and measured by the MetaFlour FRET 4.6 software. Smad3 biosensor transfection efficiency was nearly 40% and the fusion protein was seen under the fluorescence microscope. The FRET ratio of Smad3 biosensor in living 293T cells was decreased after 10 minutes incubation with the ligand of TGF-β1. The period of decreasing CFP and enhancing Citrine signals was about 300 seconds. With the technology of FRET, the TGF-β1/Smad3 signal pathway could be real time monitored dynamically under the physiological condition in living cells.
ObjectiveTo investigate the effectiveness of free sensate intercostal artery perforator flap for the hand soft tissue reconstruction.MethodsBetween March 2010 and September 2015, 19 cases of hand soft tissue defect were repaired with free sensate intercostal artery perforator flap, including 16 males and 3 females, aged from 18 to 53 years, with an average of 35.2 years. The defect was located in the dorsum of the hand in 15 cases and in the palm in 4 cases. The causes of injury were traffic accident injury in 8 cases, hot crush injury in 5 cases, strangulation injury in 4 cases, and avulsion injury in 2 cases. All of them were full-thickness skin and soft tissue defects of hand with exposure of phalanges, tendons, blood vessels, and nerves. The size of defect was 10.0 cm×7.0 cm to 17.0 cm×8.0 cm. There were 12 cases of emergency operation and 7 cases of selective operation. The thickness of flap was 10-25 mm, and the size of the flap ranged from 10.0 cm×7.5 cm to 17.0 cm×8.0 cm. The vascular pedicle of the flap was anastomosed with the snuff nest branch of the radial artery (12 cases), the main radial artery (7 cases), and there accompanying vein, and the intercostal nerve cutaneous branch of the flap was anastomosed with the lateral cutaneous nerve of the forearm. The donor site was closed directly (14 cases) or repaired with medium thickness skin graft (5 cases).ResultsAll of the flaps and skin grafts survived; the wounds in the donor and recipient sites healed by first intention. All 19 patients were followed up 10- 18 months, with an average of 12.7 months. After operation, the appearance and function of the hand recovered well, and there was no flap bloated. The two-point discrimination of the flap was 7-11 mm, with an average of 8.8 mm. Only linear scars left in the patients with direct closure of the donor site. The sensory function of the donor site was not significantly affected, and the hand function recovered satisfactorily. Conclusion Free sensate intercostal artery perforator flap is a valuable and reliable technique for the hand soft tissue defect.
For the detection and identification of abnormal nodular tissues on the body surface, a microwave sensor structure loaded with a spiral resonator is proposed in this paper, a sensor simulation model is established using HFSS software, the structural parameters are optimized, and the actual sensor is fabricated. The S21 parameters of the tissue were obtained when nodules appeared by simulation, and the characteristic relationship between the difference of S21 parameters with position was analyzed and tested experimentally. The results showed that when nodules were present in normal tissues, the curve of S21 parameter difference with position change had obvious inverted bimodal characteristics, and the extreme value of S21 parameter difference appeared when the sensor was directly above the nodules, which was easy to identify the position of nodules. It provides an objective detection tool for the identification of abnormal nodular tissues on the body surface.
Objective To investigate the relationship between graded spinal cord ischemia/reperfusion injury and somatosensory evoked potentials(SEP),neurologic function score（NFS）and the histopathological changes of spinal cord. Methods Forty rabbits were randomized and equally divided into 4 groups: shamoperation group, ischemia for 30min, 45min and 60min groups. The spinal cord ischemiareperfusion injury model was created by occlusion of the abdominal aorta in rabbits. SEP was monitored before ischemia,5,10minutes after ischemia, 15, 30 minutes, 1,2, 24 and 48 hours after reperfusion. NFS was evaluated at 6,12,24 and 48 hours after reperfusion.The pathological changes of spinal cord were observed after reperfusion 48 hours. Results The pathological characters with mild,moderate and severe spinal cord ischemia/reperfusion injury could be simulated by declamping after 30， 45 and 60 minutes infrarenal aorta crossclamping. SEP amplitude returned to normal after reperfusion 15 minutes（Pgt;0.05）and SEP latency returned to normal after reperfusion 30 minutes（Pgt;0.05）during mild spinal cord ischemia/reperfusion injury.SEP amplitude returned to normal after reperfusion 30 minutes（Pgt;0.05）and SEP latency returned to normal after reperfusion 60 minutes（Pgt;0.05）during moderate spinal cord ischemia/reperfusion injury. SEP latency increased and SEP amplitude decreased during severe spinal cord ischemia/reperfusion injury,compared with other groups, there were significant differences in SEP latency and SEP amplitude by clamping the infrarenal aorta for 60min（Plt;0.01）. With graded spinal cord ischemia/reperfusion injury, compared with shamoperation group, spinal cord ischemiareperfusion groups had significant differences in NFS（Plt;0.01）. Conclusion SEP is much quicker in the recovery of amplitude than latency during spinal cord ischemia/reperfusion. SEP is a sensitive and accurate index for spinal cord function during ischemia/reperfusion injury. SEP monitoring spinal cord ischemia/reperfusion injury during operation provides experimental basis for clinical application.
The current quantitative methods of bilirubin have disadvantages such as high cost and low sensitivity. Due to the negative correlation between the level of serum bilirubin and the risk of cardiovascular diseases, a fluorescent ratiometric film sensor was developed aiming at bilirubin detection at low level concentration. Blue-emitting and red-emitting gold nanoclusters were assembled into the same film using layer-by-layer self-assembly technology. Detection of bilirubin was achieved based on the intensity ratio of the two nanoclusters. Bilirubin exposure causes fluorescent quenching of the film. The fluorescence intensity ratio of the two cluster probes had quantitative relationship versus bilirubin concentration. Based on this film sensor, a portable fluorescence detection system was designed for the ratiometric sensing of bilirubin. The hardware of the system was mainly composed of main control chip STM32F407, TSL237 and TSL238T optical frequency sensor. A light-avoiding dark room and detection light path were designed through three-dimensional printing to reduce the interference from ambient light and improve detection accuracy. Experimental results showed that the proposed detection system had strong anti-interference, good stability and accuracy. The linear coefficient of bilirubin detected by this system was 0.987. The system presented good results in reproducible experiments and possessed a good linear relationship with the data obtained by standard spectrofluorometer. The portable system is expected to detect serum bilirubin at low levels.
To address the challenges of capturing micro-strains in detecting esophageal motility disorders and the limitations of existing high-resolution manometry and functional intraluminal imaging probes in directly measuring esophageal tissue electrical impedance, this study proposes a novel flexible balloon sensor structure that integrates a piezoelectric film assembly with a distributed impedance electrode array. Using the electrical analysis module in the finite element analysis (FEA) software, simulations of the forward problem for esophageal impedance detection were conducted to optimize the excitation source parameters, and a physical prototype was fabricated. Under a relative excitation mode with a voltage sensitivity of 2.059%, the voltage output characteristics of the impedance electrode array were analyzed during linear changes in the balloon filling volume. Based on the performance variation of the piezoelectric film assembly, 80% was selected as the optimal filling volume. Force-electric coupling tests were conducted on the balloon sensor using a pressure testing platform, revealing that both the piezoelectric film assembly inside the balloon and the impedance electrodes outside the balloon exhibited significant load differentiation characteristics as the force application point shifted. In summary, this balloon sensor facilitates the localization of force application while simultaneously analyzing esophageal tissue properties, offering a novel diagnostic approach and objective tool for esophageal disease detection.
Plantar pressure distribution can reflect the force of several key points on foot while standing and walking. A comprehensive understanding of the plantar pressure distribution makes great sense in the following aspects:the understanding of the normal foot biomechanics and function, clinical diagnosis, measurement of disease extent, postoperative efficacy evaluation, and rehabilitation research. A simple plantar pressure measurement device was designed in this study. This paper uses FlexiForce flexible sensor to pickup plantar pressure signal and USB A/D board to do data acquisition. The data are transferred into a laptop and processed by a VB-based software which can display, remember and replay the data. We chose patients with hallux valgus and normal people to measure the pressure distribution and make contrast analysis of plantar pressure with this device. It can be concluded that people with hallux valgus have higher pressure on the second metatarsophalangeal joint and the distribution move outward. The plantar pressure of patients postoperative could be greatly improved compared to the preoperative. The function of this device has been confirmed.
ObjectiveTo investigate the effectiveness of using a sensory prefabricated flap to repair the heel avulsion injury.
MethodsBetween August 2012 and August 2013, 6 cases of heel avulsion injury were treated. There were 4 males and 2 females, aged 16-54 years (mean, 29 years). The causes were crush injury in 4 cases and wheel twist injury in 2 cases. The injury to admission time was 2-6 hours (mean, 4 hours). The size of skin avulsion ranged from 5 cm×3 cm to 15 cm×8 cm. Avulsion skin had no replanted condition. At one stage operation, the avulsed heel skin soft tissue was made the full thickness skin graft which was fostered on the anterolateral thigh with lateral circumflex femoral artery perforator, and the lateral femoral cutaneous nerve was put beneath the skin to prefabricate the prefabricated flap; at two stage operation, the prefabricated skin flap pedicled with lateral circumflex femoral artery was used to repair the wound, and the lateral femoral nerve was anastomosed with the calcaneal nerve to reconstruct the feeling.
ResultsSix prefabricated flaps all survived, and re-plantation flaps survived after operation. The wounds healed by first intention at donor site and recipient site. The patients were followed up 1-2 years (mean, 1.5 years). The flaps had satisfactory appearance and soft texture. At 1 year after operation, the sensation of the flaps was S3, with two-point discrimination of 22-27 mm (mean, 24.3 mm). According to ZHANG Ming's evaluation standards, the results were excellent in 5 cases, and good in 1 case. The patients could walk normally or with weight-bearing; only linear scar formed at the donor site.
ConclusionFor patients with heel soft tissue avulsion injury without replantation qualification, a sensory prefabricated flap by the avulsed heel skin soft tissue can transplanted to repair the heel defect. Satisfactory effectiveness can be obtained in heel appearance and function recovery.
Non-drug treatment of hypertension has become a research hotspot, which might overcome the heavy economic burden and side effects of drug treatment for the patients. Because of the good treatment effect and convenient operation, a new treatment based on slow breathing training is increasingly becoming a kind of physical therapy for hypertension. This paper explains the principle of hypertension treatment based on slow breathing training method, and introduces the overall structure of the portable blood pressure controlling instrument, including breathing detection circuit, the core control module, audio module, memory module and man-machine interaction module. We give a brief introduction to the instrument and the software in this paper. The prototype testing results showed that the treatment had a significant effect on controlling the blood pressure.
