2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)最新文献

{"title":"PLGA nanoparticles for calcitriol delivery","authors":"M. J. Ramalho, J. Loureiro, B. Gomes, Manuela F. Frasco, M. Coelho, M. C. Pereira","doi":"10.1109/ENBENG.2015.7088884","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088884","url":null,"abstract":"Calcitriol, the active metabolite of Vitamin D3, is a potential anticancer agent but exhibits several drawbacks. Therefore, new therapeutic strategies, as specific drug delivery systems, must be developed in order to overcome those limitations. The aim of this work was to prepare poly(lactide-coglycolide) nanoparticles as drug delivery vehicles for calcitriol. Two formulation parameters, vitamin/polymer ratio and sonication time, were firstly studied and discussed using cholecalciferol as a drug model. Then, calcitriol-loaded poly(lactide-coglycolide) nanoparticles with controlled sizes and properties were prepared. The nanoparticles remained stable at storage conditions for several weeks and they were successfully lyophilized to increase their shelf-life using a crioprotectant. In vitro studies using two human cancer cell lines, S2-013 and A549, demonstrated that bare PLGA NPs are biocompatible.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113931575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Human gait analysis using instrumented shoes","authors":"H. Sobral, A. Vieira, J. Ferreira, Paulo Ferreira, Stephane Cruz, M. Crisostomo, A. Coimbra","doi":"10.1109/ENBENG.2015.7088807","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088807","url":null,"abstract":"This paper describes a human gait analysis and characterization system, that automatically assesses the severity of gait disorders, using low cost 3D instrumented shoes. Human gait pattern analysis has an increasing importance in rehabilitation medicine, sports and other areas. Therefore, understanding gait patterns enables medical staff to follow recovery processes of patients and adjust their treatments, as well as it permits to evaluate the efficiency of athletes' gait in order to improve their performances. At the present time, there are many systems that measure some parameters that characterize human gait, like the vertical component of the ground reaction force (GRF), which is used to map the plantar pressure and to compute the centre of pressure's location (CoP). Most present solutions use force plates and insoles with pressure or force sensors [1-3]. However, force plates restrict the number of steps that can be done and sometimes insoles don't adjust very well to the footwear. The presented computerized system consists of a pair of low cost instrumented shoes designed to read and collect the three components of the GRF during the human gait using thin force sensors. Data is sent to a computer via a wireless protocol. They can be processed and visualized in graphs showing the three curves of the GRF and the trajectory of the CoP. These instrumented shoes have already been tested in persons with and without physical disorders to build a gait database. These persons had different ages, weights and heights, and walked at five different velocities (slow, very slow, normal, fast and very fast). Time curves of the GRF, biometric parameters and the walking velocity are used as inputs to a neuronal network in order to generate reference gait patterns for people with different physical characteristics. Results were consistent with those in the literature. Some tests have been done in a public hospital, with patients subjected to ligamentoplasty two years ago, because of the rupture of their knee's anterior cruciate ligament. The aim of the current work is to infer their recovery degree, comparing their GRF and CoP curves with the reference gait patterns previously obtained. Preliminary results show that it is possible to quantify differences in gait patterns of non-healthy people. The presented system can thus be an important gait disorder diagnostic tool as it objectively quantify gait disorders, something that is harder to get with the present subjective analysis.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131147139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D gait analysis in rheumatoid arthritis postmenopausal women with and without falls history","authors":"P. Aleixo, J. Abrantes","doi":"10.1109/ENBENG.2015.7088880","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088880","url":null,"abstract":"The aim of this study was to compare gait biomechanical parameters related with falls, in rheumatoid arthritis postmenopausal women (N=22) with and without falls history. A 3D model was used. The Vicon® Motion Capture System recorded kinematics data (9 MX1.3 cameras, 200Hz) synchronized with a force plate (AMTI BP400600-200, 1000Hz). The Vicon® Nexus software (1.7.1) based on an integrated model of 41 reflective markers and subject anthropometric data, developed the 3D spatial localization of joints centers and the model mechanical segments. Subjects performed 14 valid trials (7 left and 7 right foot-steps on force plate). The decrease of centre of mass anteroposterior velocity and heel anteroposterior velocity in RA postmenopausal women with falls history may have been the result of an adaptation to ensure a safer gait. The variability found in heel anteroposterior velocity of the RA postmenopausal women with falls history may indicate a lower proprioceptive control.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117300957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reliability of a wearable system to evaluate ambulatory autonomic activity","authors":"C. Tavares, V. Geraldes, I. Rocha, S. Bastier, Anne Pavy Le-Traon","doi":"10.1109/ENBENG.2015.7088863","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088863","url":null,"abstract":"Recent clinical research directs up to provide personalized health care, adapted to each patient and to his clinical situation. With this work, we showed that a wearable device with heart rate (HR), respiratory and temperature sensors could be used, under certain technical and environmental requirements, for a reliable autonomic evaluation outside the confinement of an autonomic laboratory.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129602113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new method for predicting epilepsy seizure","authors":"Abdellatif Abuimara","doi":"10.1109/ENBENG.2015.7088840","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088840","url":null,"abstract":"In this paper I present a new method for predicting epilepsy seizure. This method depends on classification of the signal amplitudes of obtained EEG signals from healthy and non-healthy persons in different situations, like EEG signals during eyes opened and eyes closed, EEG signals from healthy and non-healthy persons during times with seizure and without seizure and from different parts of brain. This method is unique because it is new simple and promised and with it a coming seizure can be simply predicted from the small time interval before its happening. Then comparisons between the classified measurements have carried out. And finally the results were obtained. The processed signals were hundred measurements for each patient and each healthy person. The results show that this is a promised method to predict epilepsy seizure. Unfortunately this prediction of the seizure can not made long time before the seizure but only short time before it that why it waits enhancements.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116294329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A discontinuous Galerkin scheme for solving 2D wave propagation in anisotropic materials","authors":"A. Araújo, S. Barbeiro, Maryam Khaksar Ghalati","doi":"10.1109/ENBENG.2015.7088866","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088866","url":null,"abstract":"Optical Coherence Tomography, OCT, is a relatively recent imaging technique that allows high-resolution imaging of the retina. It relies in certain optical characteristics of light to provide information of the eye fundus, facilitating the diagnosis of some eye pathologies [13]. In order to better understand the information carried in an OCT, we must model in detail the behavior of the electromagnetic wave as it travels through the sample with Maxwell's equations. In this work we discuss the numerical discretization of the time-dependent Maxwell's equations using a leap-frog type discontinuous Galerkin (DG) method. Nodal DG method [4] was chosen for the integration in space due to its high-order of accuracy and its ability to handle complex geometries. We focus on numerically illustrate the convergence properties of fully discrete schemes. In the model we consider anisotropic permittivity tensors which arise naturally in our application of interest [1].","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131647809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hand therapist: A rehabilitation approach based on wearable technology and video gaming","authors":"Rastislav Lipovský, H. Ferreira","doi":"10.1109/ENBENG.2015.7088817","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088817","url":null,"abstract":"Hand impairment after stroke is quite debilitating. Present hand rehabilitation approaches, although useful, are still limited as they often require the constant help of a technician or caregiver and also because they are based on repetitive training which may be demo-tivating [1]. More advanced approaches are in development including the use of robotized systems [2]. Nonetheless, these systems are still expensive and require expert support. Here, we show the proof-of-concept of a hand rehabilitation system, dubbed “hand therapist”, inspired in video gaming devices and software which is comprised of the Myo armband, a home-built robotic glove and Unity3D, a video game development engine. With this approach we aim at a solution that combines performance, low-cost and engagement/motivation in hand therapy. The Myo armband is a ~200 euros wearable device comprised of a 9-axis inertial measurement unit (IMU) and 8 electromyography (EMG) sensors [3]. The device thus provides two kinds of data, spatial and gestural data, respectively. Spatial data informs about the orientation and movement of the user's arm whilst gestural data informs what the user is doing with his/her hand in the form of one of several pre-set poses. All data is communicated via Bluetooth with Unity3D. A ~100 euros robotic glove was built based on a sports glove, nylon wiring, two stepper motors for hand opening/closing, and an Arduino Uno board for control and communication with Unity3D. Touch buttons were also used to detect a fully opened/closed hand. A game was built in Unity 3D for hand training in which the user must grab, hold, transport and drop a cube in several increasingly difficult puzzle levels. In the game the user sees virtual hands/arms that replicates the user's movements such that the user can feel more immersed in the game. Presently, the game works as follows: the user wears the Myo armband in the healthy forearm and executes the required movements, which are translated into the movement of the virtual hand/arm. Hand movements are then replicated into the movement of the robotic glove the user wears in the impaired hand. These movements are also simultaneous translated into the movement of a corresponding virtual hand/arm. So far the system was tested only with healthy subjects, but tests with stroke patients are planned. In the future, we also plan to combine the system with an additional Myo armband unit such that is possible to monitor both hand/arms simultaneously for an improved interaction of the user with the game. In this work we proposed a low-cost (<;500 euros) and engaging solution for hand rehabilitation is possible based on gaming devices and software. Future studies with patients are still required.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114237918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A medical device for support of the ankle pathologies diagnosis","authors":"R. Ferreira, F. Silva, P. Flores, A. Leal, J. Espregueira-Mendes","doi":"10.1109/ENBENG.2015.7088889","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088889","url":null,"abstract":"Of all musculoskeletal system, the tibiotarsal joint is the structure where it was registered the higher incidence of injuries, both along the realization of daily activities as during the sports practice. The motivation for this investigation came from the lack of reliable mechanical systems that permit the quantification of the different motions described at the ankle articulation. So, with the goal of facilitate and optimize the diagnosis process, either of patient's point of view, such as radiologist and the orthopedists, is presented in this paper the project of a medical device for supporting the diagnosis of the ankle pathologies. With the adopted solution it is possible to associate an imaging exam (e.g. magnetic resonance) to a physical effort in order to define the mobile limit of the ankle structure, which constitutes an added-value for the health professionals.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"145 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114371348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gamma distribution model in breast cancer diffusion-weighted imaging","authors":"Filipa Borlinhas, L. Nogueira, S. Brandão, R. Nunes, J. Loureiro, I. Ramos, H. Ferreira","doi":"10.1109/ENBENG.2015.7088819","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088819","url":null,"abstract":"Summary form only given. Many diffusion models have been proposed in order to obtain more information from breast tumor tissues through Magnetic Resonance Imaging (MRI) (1). The Gamma distribution (GD) may model MRI signal decay based on a statistical approach. This model considers the Theta parameter, which indicates the statistical dispersion of the distribution, and the k parameter, which is responsible for the probability distribution shape. If Theta shows higher values, then there will be a more spread out distribution and if k shows lower values the distribution shape will be more affected, which would be expected in malignant tumors due to tissue heterogeneity (1). The purpose of this study was to evaluate if GD model is capable of distinguishing between different breast tumors. Materials and Methods: In this study 85 breast tumor lesions were analyzed, including 17 benign lesions (Fibroadenoma, FA) and 68 malignant lesions (43 Invasive Ductal Carcinomas, IDC 19 Invasive Lobular Carcinomas, ILC and 6 Ductal Carcinoma in situ, CDIS). Informed consent was obtained for all patients. Data were acquired using a 3T MRI scanner with a dedicated breast coil and a DWI sequence with 3 orthogonal diffusion gradient directions and 8 b values between 0 and 3000s/mm2. Theta and k parameters were acquired from fitting data to the GD model, and mean values were obtained to compare between benign and malignant lesions, and between histological types. Non-parametric statistics were used (α=0.05). Results and Discussion: Significantly lower Theta and higher k values were observed in benign lesions ((0.65±0.43)×10-3mm2/s, 4.29±1.90, respectively) when compared to malignant lesions ((0.97±0.50)×10-3mm2/s, 1.23±0.52, respectively). It was also possible to differentiate FA from IDC lesions with both Theta and k probably due to IDC heterogeneity, which restricts diffusion. Unlike other diffusion model parameters, these were able to differentiate FA and ILC, and FA and CDIS lesions, suggesting that the GD model could bring advantages over other diffusion models in characterizing breast tumors. This study was partly funded by Fundação para a Ciência e Tecnologia (FCT) under the grant PEst-OE/SAU/UI0645/2014.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125427224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a tool for automatic classification of intratumoral heterogeneity of lung cancers based on PET/CT intensity values","authors":"Carlos Pereira, C. Gomes, F. Caramelo","doi":"10.1109/ENBENG.2015.7088870","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088870","url":null,"abstract":"Intratumoral heterogeneity, typical of solid tumors, results from the coexistence of various subpopulations of tumor cells with different biological characteristics. The objective of this work was to develop an algorithm for the analysis and classification of intratumoral heterogeneity in lung cancers. The classification algorithm was based on features obtained from PET/CT images of the tumors. Delimited regions containing the tumors were defined by experience observers, who also classified each tumor regarding its degree of heterogeneity using a scale of four levels for heterogeneity. Features were created based on the joint histogram built from CT and PET data, which were then used to implement two classifier algorithms: one ordinal regression exploiting the four levels of heterogeneity and a logistic regression checking only two. Statistical analysis was carried out using IBM-SPSS Statistics 20 with a level of significance of 0.05. The models developed show good accuracy, mainly the binary classification algorithm (90%).","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128055392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}