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1.
Article in English | WPRIM (Western Pacific) | ID: wpr-1003170

ABSTRACT

BACKGROUND@#The formation of an inhibitory inflammatory microenvironment after spinal cord injury (SCI) remains a great challenge for nerve regeneration. The poor local microenvironment exacerbates nerve cell death; therefore, the reconstruction of a favorable microenvironment through small-molecule drugs is a promising strategy for promoting nerve regeneration. @*METHODS@#In the present study, we synthesized curcumin-loaded micelle nanoparticles (Cur-NPs) to increase curcumin bioavailability and analyzed the physical and chemical properties of Cur-NPs by characterization experiments. We established an in vivo SCI model in rats and examined the ability of hind limb motor recovery using Basso–Beattie– Bresnahan scoring and hind limb trajectory assays. We also analyzed neural regeneration after SCI using immunofluorescence staining. @*RESULTS@#The nanoparticles achieved the intelligent responsive release of curcumin while improving curcumin bioavailability. Most importantly, the released curcumin attenuated local inflammation by modulating the polarization of macrophages from an M1 pro-inflammatory phenotype to an M2 anti-inflammatory phenotype. M2-type macrophages can promote cell differentiation, proliferation, matrix secretion, and reorganization by secreting or expressing pro-repair cytokines to reduce the inflammatory response. The enhanced inflammatory microenvironment supported neuronal regeneration, nerve remyelination, and reduced scar formation. These effects facilitated functional repair in rats, mainly in the form of improved hindlimb movements. @*CONCLUSION@#Here, we synthesized pH/temperature dual-sensitive Cur-NPs. While improving the bioavailability of the drug, they were also able to achieve a smart responsive release in the inflammatory microenvironment that develops after SCI. The Cur-NPs promoted the regeneration and functional recovery of nerves after SCI through anti-inflammatory effects, providing a promising strategy for the repair of SCIs.

2.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1009017

ABSTRACT

OBJECTIVE@#To review targeted muscle reinnervation (TMR) surgery for the construction of intelligent prosthetic human-machine interface, thus providing a new clinical intervention paradigm for the functional reconstruction of residual limbs in amputees.@*METHODS@#Extensively consulted relevant literature domestically and abroad and systematically expounded the surgical requirements of intelligent prosthetics, TMR operation plan, target population, prognosis, as well as the development and future of TMR.@*RESULTS@#TMR facilitates intuitive control of intelligent prostheses in amputees by reconstructing the "brain-spinal cord-peripheral nerve-skeletal muscle" neurotransmission pathway and increasing the surface electromyographic signals required for pattern recognition. TMR surgery for different purposes is suitable for different target populations.@*CONCLUSION@#TMR surgery has been certified abroad as a transformative technology for improving prosthetic manipulation, and is expected to become a new clinical paradigm for 2 million amputees in China.


Subject(s)
Humans , Artificial Limbs , Muscle, Skeletal , Neurosurgical Procedures , Plastic Surgery Procedures , Prosthesis Implantation
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 406-409, 2017 Jul.
Article in English | MEDLINE | ID: mdl-29059896

ABSTRACT

In the practical use of an electromyography (EMG) pattern-recognition based myoelectric prosthesis, the variation of force levels to do a motion would be inevitable, which will cause a change of EMG patterns. Therefore, the force variation will decay the performance of a trained classifier. In this study, the common spatial pattern (CSP) method was proposed with an attempt to improve the robustness of EMG-PR based classifier against force variation. The EMG signals were acquired from three able-bodied subjects when they were performing the motions at low, medium, and high force levels, respectively. And in the pattern recognition, CSP features were extracted from the EMG signals for motion classification. By comparing the classification accuracies between the CSP and the commonly used time-domain (TD) features, the CSP features showed a better robustness against force variation with an increment of 5.3% of the average classification accuracy. Especially, the classification accuracy of a classifier was 84.2% when tested at low force level by using CSP features, which was 18.5% higher than that of the TD features. These preliminary results suggest that using CSP features may increase the robustness of EMG-based myoelectric control.


Subject(s)
Electromyography , Algorithms , Mechanical Phenomena , Motion , Pattern Recognition, Automated , Prostheses and Implants
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 2271-2274, 2017 Jul.
Article in English | MEDLINE | ID: mdl-29060350

ABSTRACT

Motion recognition is an important application of electromyography (EMG) analysis. While discrete motions such as hand open, hand close and wrist pronation have been extensively investigated, studies on combined motions involving two or more degrees of freedom (DOFs) are relatively few and the classification accuracy of the combined motions reported in previous studies is barely satisfactory. To improve the accuracy of the combined motion recognition, common spatial pattern (CSP) was employed in this study to extract spatial features. 18 forearm motion classes, consisted of 8 discrete motions and 10 combined motions, were classified by the proposed method. Our results showed that the accuracy rate of CSP features was 96.3%, which outperformed the commonly used time-domain (TD) features by 2.4% and TD combined with auto-regression coefficients (TDAR) by 0.6%. Moreover, CSP features cost noticeable much less time than TDAR and quite less time than TD in testing. These results suggest that CSP features could be a better feature set for multi-DOF myoelectric control than conventional features.


Subject(s)
Motion , Algorithms , Electromyography , Hand , Humans , Pattern Recognition, Automated , Wrist
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 2325-2328, 2017 Jul.
Article in English | MEDLINE | ID: mdl-29060363

ABSTRACT

Power line interference in the surrounding environment could usually introduce many difficulties when collecting and analyzing physiological signals. Since power line interference is usually several orders of amplitude larger than the physiological electrical signals, methods of suppressing power line interference should be considered during the signal acquisition. Many studies used a hardware or software band-stop filter to suppress power line interference but it could easily cause attenuations and distortions to the signal of interest. In this study, two kinds of methods that used different signals to drive the shields of the electrodes were proposed to reduce the impacts of power line interference. Three channels of two physiological signals (ECG and EMG) were simultaneously collected when the electrodes were not shielded (No-Shield), shielded by ground signals (GND-Shield) and shielded by buffered signals of the corresponding electrodes (Active-Shield), respectively, on a custom hardware platform based on TI ADS1299. The results showed that power line interference would be significantly suppressed when using shielding approaches, and the Active-Shield method could achieve the best performance with a power line interference reduction up to 36dB. The study suggested that the Active-Shield method at the analog front-end was a great candidate to reduce power line interference in routine acquisitions of physiological signals.


Subject(s)
Signal Processing, Computer-Assisted , Algorithms , Electricity , Electrocardiography , Electrodes , Software
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3413-3416, 2017 Jul.
Article in English | MEDLINE | ID: mdl-29060630

ABSTRACT

Tooth contour segmentation from dental computerized tomography (CT) images is one of the fundamental steps in reconstructing the three-dimensional models of teeth. However, existing methods depend on the tooth shape similarity between adjacent slices, and have difficulty to segment these angled teeth whose contour shapes from adjacent slices may differ a lot. This study proposes a new method for contour segmentation of angled teeth from CT images. The volume of interest (VOI) of target tooth and corresponding tooth axis are first extracted from volumetric CT images. Local images within the VOI of target tooth are then rotated such that the tooth axis in the rotated images is perpendicular to the transverse section. Tooth contours are finally segmented from the rotated images using a hybrid level set model slice-by-slice. Experimental results verified that the proposed method was effective to segment contours of angled teeth from CT images.


Subject(s)
Tooth , Algorithms , Cone-Beam Computed Tomography , Imaging, Three-Dimensional , Tomography, X-Ray Computed
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3860-3863, 2017 Jul.
Article in English | MEDLINE | ID: mdl-29060740

ABSTRACT

The Modified Ashworth Scale (MAS) is the gold standard in clinical for grading spasticity. However, its results greatly depend on the physician evaluations and are subjective. In this study, we investigated the feasibility of using support vector machine (SVM) to objectively assess elbow spasticity based on both surface electromyography (sEMG) and mechanomyography (MMG). sEMG signals and tri-axial accelerometer mechanomyography (ACC-MMG) signals were recorded simultaneously on patients' biceps and triceps when they extended or bended elbow passively. 39 post-stroke patients participated in the study, and were divided into four groups regarding MAS level (MAS=0, 1, 1+ or 2). The three types of features, root mean square (RMS), mean power frequency (MPF), and median frequency (MF), were calculated from sEMG and MMG signal recordings. Spearman correlation analysis was used to investigate the relationship between the features and spasticity grades. The results showed that the correlation between MAS and each of the five features (MMG-RMS of the biceps, MMG-RMS of the triceps, the EMG-RMS of the biceps, EMG-RMS of the triceps, EMG-MPF of the triceps) was significant (p<;0.05). The four spasticity grades were identified with SVM, and the classification accuracy of SVM with sEMG, MMG, sEMG-MMG were 70.9%, 83.3%, 91.7%, respectively. Our results suggest that using the SVM-based method with sEMG and MMG to assess elbow spasticity would be suitable for clinical management of spasticity.


Subject(s)
Elbow , Biomedical Technology , Electromyography , Humans , Muscle Spasticity , Muscle, Skeletal , Myography , Support Vector Machine
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 4439-4442, 2017 Jul.
Article in English | MEDLINE | ID: mdl-29060882

ABSTRACT

Continuous electrocardiogram (ECG) monitoring is significant for prevention of heart disease and is becoming an important part of personal and family health care. In most of the existing wearable solutions, conventional metal sensors and corresponding chips are simply integrated into clothes and usually could only collect few leads of ECG signals that could not provide enough information for diagnosis of cardiac diseases such as arrhythmia and myocardial ischemia. In this study, a wearable 12-lead ECG acquisition system with fabric electrodes was developed and could simultaneously process 12 leads of ECG signals. By integrating the fabric electrodes into a T-shirt, the wearable system would provide a comfortable and convenient user interface for ECG recording. For comparison, the proposed fabric electrode and the gelled traditional metal electrodes were used to collect ECG signals on a subject, respectively. The approximate entropy (ApEn) of ECG signals from both types of electrodes were calculated. The experimental results show that the fabric electrodes could achieve similar performance as the gelled metal electrodes. This preliminary work has demonstrated that the developed ECG system with fabric electrodes could be utilized for wearable health management and telemedicine applications.


Subject(s)
Electrocardiography , Electrodes , Equipment Design , Textiles , Wearable Electronic Devices
9.
Journal of Practical Radiology ; (12): 1851-1854,1862, 2017.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-664056

ABSTRACT

Objective To investigate the correlation between mammographic findings and different molecular subtypes of breast cancer.Methods Totally 84 patients with breast cancer proved pathologically who underwent digital mammography examination before operation were enrolled.All cases were examined by immunohistochemical staining,the expression levels of estrogen receptor(ER),progesterone receptor (PR)and human epidermal growth factor receptor-2(HER-2)in tumor cells were analyzed.They were classified into four molecular subtypes:Luminal A,Luminal B,HER-2 + and Basal-like tumors according to their expression levels.The correlation between mammographic findings and different molecular subtypes of breast cancer were analyzed.Results Among the 84 cases of breast cancer,there were significant differences between mass shadow and mass shape in the four subtypes of tumors(P<0.05).Luminal A,Luminal B breast cancer showed more irregular edge of the tumor;HER-2 + breast cancer with more malignant calcifications,of which simple calcifications of breast cancer were more;Basal-like breast cancer with regular shape,clear border shadow,rarely accompanied by malignant calcifications.Conclusion Mammographic features of breast cancer can predict its molecular subtypes to some extent,which can provide objective basis for the selection of clinical preoperative treatment protocols.

10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 867-870, 2016 Aug.
Article in English | MEDLINE | ID: mdl-28268461

ABSTRACT

Motion classification system based on surface Electromyography (sEMG) pattern recognition has achieved good results in experimental condition. But it is still a challenge for clinical implement and practical application. Many factors contribute to the difficulty of clinical use of the EMG based dexterous control. The most obvious and important is the noise in the EMG signal caused by electrode shift, muscle fatigue, motion artifact, inherent instability of signal and biological signals such as Electrocardiogram. In this paper, a novel method based on Canonical Correlation Analysis (CCA) was developed to eliminate the reduction of classification accuracy caused by electrode shift. The average classification accuracy of our method were above 95% for the healthy subjects. In the process, we validated the influence of electrode shift on motion classification accuracy and discovered the strong correlation with correlation coefficient of >0.9 between shift position data and normal position data.


Subject(s)
Algorithms , Electromyography/methods , Signal Processing, Computer-Assisted , Artifacts , Electrodes , Electromyography/instrumentation , Hand , Humans , Motion , Muscle Fatigue/physiology , Wrist
11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 1050-1053, 2016 Aug.
Article in English | MEDLINE | ID: mdl-28268505

ABSTRACT

Estimation of tooth axis is needed for some clinical dental treatment. Existing methods require to segment the tooth volume from Computed Tomography (CT) images, and then estimate the axis from the tooth volume. However, they may fail during estimating molar axis due to that the tooth segmentation from CT images is challenging and current segmentation methods may get poor segmentation results especially for these molars with angle which will result in the failure of axis estimation. To resolve this problem, this paper proposes a new method for molar axis estimation from CT images. The key innovation point is that: instead of estimating the 3D axis of each molar from the segmented volume, the method estimates the 3D axis from two projection images. The method includes three steps. (1) The 3D images of each molar are projected to two 2D image planes. (2) The molar contour are segmented and the contour's 2D axis are extracted in each 2D projection image. Principal Component Analysis (PCA) and a modified symmetry axis detection algorithm are employed to extract the 2D axis from the segmented molar contour. (3) A 3D molar axis is obtained by combining the two 2D axes. Experimental results verified that the proposed method was effective to estimate the axis of molar from CT images.


Subject(s)
Imaging, Three-Dimensional/methods , Molar/diagnostic imaging , Tomography, X-Ray Computed/methods , Algorithms , Cone-Beam Computed Tomography/methods , Humans , Principal Component Analysis
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 6030-6033, 2016 Aug.
Article in English | MEDLINE | ID: mdl-28269627

ABSTRACT

Orthodontic force simulation is very important for the guidance of clinical orthodontic treatment. Previous works were mainly conducted by directly loading the force on a single or a few teeth. However, in clinic, the orthodontic force is provided by loading orthodontic appliances, and there currently is no appropriate way to measure the force on the teeth provided by the loaded appliances. This study presents a method to simulate the orthodontic force of a whole Tooth-Periodontal Ligament-Bone Complex (TPBC) by directly loading the archwire to the dentition applying the finite element method. A 3D TPBC model was reconstructed from CT images, and models of brackets and the archwire were also built. The loading procedure of the archwire was implemented by simulating the deformation and displacement of the archwire before and after the loading, and the stress of the archwire induced by the deformation and displacement was obtained. Then, the stress was applied to the brackets, and the corresponding orthodontic force of the TPBC was simulated. By applying the method, archwire designed according to the planned dentition shape was loaded successfully to the original dentition, and the orthodontic force of the TPBC was obtained.


Subject(s)
Models, Dental , Orthodontic Appliances , Periodontal Ligament/physiology , Tooth/physiology , Humans , Stress, Mechanical
13.
Journal of Practical Radiology ; (12): 1137-1141, 2016.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-496492

ABSTRACT

Objective To quantitatively analyze the fund theses published in the Journal of Practical Radiology(JPR)and Chinese Journal of Radiology(CJR)in order to detect effective approaches to the improvement of the journal quality and academic level of the JPR.Methods The number of funds-supported theses published,the ratio of fund theses,grade,regional,source of institutions and publication time-lag distribution of the fund theses were statistically analyzed by using bibliometrics in the two journals in 2013.Re-sults Six hundred and eighteen theses were published in JPR in 2013,the total number of fund theses were 137(accounted for 22.2% of total articles),the ratio of fund theses were 0.22,the provincial and municipal fund theses accounted for 59.2%.All fund theses were from 23 regions and 82 institutions throughout the country.The average of publication time-lag was 235.6 days.Three hundred and thirteen theses were published in CJR in 2013,the total number of fund theses were 97(accounted for 31.0% of total articles),the ratio of fund theses were 0.31,the provincial and municipal fund theses accounted for 32.0%.All fund theses were from 18 regions and 70 institutions throughout the country.The average of publication time-lag was 228.4 days.Conclusion JPR has its own superi-ority,meanwhile,it also has a significant disparity and insufficiency comparing to CJR.In order to further promote the quality conno-tations and the academic level of JPR,efforts should be made on subject selection and planning,initiative collection of manuscripts, priority publishment to excellent manuscripts,shortening publication time-lag,etc.Additionally,a database of core authors and ex-perts should be established.

14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 2733-6, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26736857

ABSTRACT

The medial olivocochlear complex (MOC) is an auditory nucleus that projects efferent nerve fibers to control the behaviors of both sides of the cochlea. Otoacoutsic emissions (OAEs) are by-products the activities of the outer hair cells (OHCs) in the cochlea and could be used as a noninvasive way to study the efferent control of the MOC. However, existing results regarding the efferent control are quite controversial and often restricted to a rather limited frequency range. In this study, a new method of measuring stimulus frequency otoacoustic emissions (SFOAEs) with the presence of a contralateral acoustic stimulation (CAS) was proposed to study the efferent control over the cochlea. SFOAEs were measured with swept tones with time varying frequencies so that SFOAE spectra with and without the presence of the CAS could be compared with high frequency-resolution. The results showed that there was consistent decrease in the amplitude of the swept-tone SFOAEs across a wide frequency range from 0.5 to 8 kHz when the CAS was presented, suggesting an outstanding attenuation of OHC activities by the efferent control from the MOC. The SFOAE decrease with the presence of the CAS might provide a new approach to measure the strength of the efferent control and to evaluate the functional status of the central auditory pathway.


Subject(s)
Acoustic Stimulation , Auditory Pathways , Cochlea , Nerve Fibers , Otoacoustic Emissions, Spontaneous
15.
Chinese Journal of Cancer ; (12): 106-112, 2013.
Article in English | WPRIM (Western Pacific) | ID: wpr-295801

ABSTRACT

In 2012, the National Central Cancer Registry (NCCR) of China collected cancer registration information for the year 2009 from local cancer registries and analyzed it to describe the incidences and mortalities of cancers in China. Based on the data quality criteria from NCCR, data from 104 registries covering 85,470,522 people (57,489,009 in urban areas and 27,981,513 in rural areas) were checked and evaluated. The data from 72 registries were qualified and accepted for the cancer registry annual report in 2012. The total cancer incident cases and cancer deaths were 244,366 and 154,310, respectively. The morphologically verified cases accounted for 67.23%, and 3.14% of the incident cases only had information from death certifications. The crude incidence in the Chinese cancer registration areas was 285.91/100,000 (317.97/100,000 in males and 253.09/100,000 in females). The age-standardized rates for incidences based on the Chinese standard population (ASRIC) and the world standard population (ASRIW) were 146.87/100,000 and 191.72/100,000, respectively, with a cumulative incidence of 22.08%. The cancer mortality in the Chinese cancer registration areas was 180.54/100,000 (224.20/100,000 in males and 135.85/100,000 in females). The age-standardized rates for mortalities based on the Chinese standard population(ASRMC) and the world standard population (ASRMW) were 85.06/100,000 and 115.65/100,000, respectively, and the cumulative mortality was 12.94%. Lung cancer, gastric cancer, colorectal cancer, liver cancer, esophageal cancer, pancreatic cancer, encephaloma, lymphoma, female breast cancer, and cervical cancer were the most common cancers, accounting for 75% of all cancer cases. Lung cancer, gastric cancer, liver cancer, esophageal cancer, colorectal cancer, pancreatic cancer, breast cancer, encephaloma, leukemia, and lymphoma accounted for 80% of all cancer deaths. The cancer registration's population coverage has been increasing, and its data quality is improving. As the basis of the cancer control program, the cancer registry plays an important role in directing anticancer strategies in the medium and long term. Because cancer burdens are different in urban and rural areas in China, prevention and control efforts should be based on practical situations.


Subject(s)
Female , Humans , Male , China , Epidemiology , Incidence , Neoplasms , Epidemiology , Mortality , Registries
16.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-442255

ABSTRACT

With the continuous improvement and innovation of modern engineering technology and biomedical technology,many efforts and process have been made on multifunctional prosthesis systems and have gained more and more attentions.The multifunctional powered prosthesis has become one of the research areas in the current muscular rehabilitation medicine and neural engineering.The bionic control of prosthesis,especially using the neural signal to control the upper prosthesis effectively,is one of the most important fields of prosthesis technology.Choosing the proper neural signals seems to be particularly important for bionic prosthetic control strategy.Currently,several different signal controls such as EMG control,EEG control,voice signal control and peripheral nerve signal control have been proposed and investigated for the bionic control of multi-function prosthesis.This paper reviews the latest efforts and progress of multifunctional upper prosthesis.

17.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-408169

ABSTRACT

BACKGROUND: With conversion of medical patterns and revolution of healthy concept, temperament, psychological health and behavior become key topics for child care and are paid more and more attention nowadays.OBJECTIVE: To survey the status quo of psychological and behavior problems and distribution of temperamental types through questionnaire for children in Guiyang.DESIGN: Randomized cluster sampling and cross-sectional study.SETTING: Guiyang Institute for Mother and Child Health.PARTICIPANTS: Twelve settings were randomly selected from 33 duty units for child care in Guiyang. Children aged 1-6 years suffered from health check at survey stage, and those with severe body diseases and abnormal intelligence were excluded.METHODS: Problems of psychological health and behavior and distribution of temperamental types for children were surveyed with self-made psychological health scale, Chinese temperament scale for 1-3-year children,Chinese temperament scale for 3-7-year children, behavior scale for 2-3-year children and Achenbach's children behavior scale standardized by Shanghai Mental Health Center. All questionnaires were answered by parents and taken back on the spot. After 2-4 weeks, several children were randomly selected to refill in the questionnaires mentioned above to measure reliability again.MAIN OUTCOME MEASURES: Status quo of psychological and behavior problems, distribution of temperamental types and effect of social environment on temperament and behavior.RESULTS: ① Distribution of temperamental types was divided into easy nurture, difficult nurture, nearly easy nurture, nearly difficult nurture and slow development, and the percentage was 35.58%, 4.21%, 39.70%, 7.37%and 13.14%. ② Total ratio of psychological problems was 94.50%, and ratios of children in various temperamental types were 98.91%, 97.26%,96.19%, 94.05% and 93.13% (P < 0.01). ③ Total ratio of behavior problems was 19.57%, and ratios of children in various temperamental types were 31.76%, 26.69%, 22.58%, 21.33% and 12.72% (P < 0.01). Temperamental types and behavior problems were related to living condition, educational level of parents, marriage, supervised attitude, paternity, pregnant nutrien, illness and infirmarian, especially temperament was closely related with psychological and behavior problems.CONCLUSION: Psychological and behavior problems wildly exist among children in Guiyang and should be paid much attention. Fine personality of children can be molded through reforming relevant factors so as to decrease the incidence of psychological and behavior problems.

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