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

{"title":"Modeling partitioning of proteins in aqueous two-phase system","authors":"Dragana P. C. de Barros, S. R. R. Campos, A. Azevedo, A. Baptista, M. Aires-Barros","doi":"10.1109/ENBENG.2015.7088804","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088804","url":null,"abstract":"Advances in biotechnology have made possible the production of a large number of new proteins important to the food, pharmaceutical, and chemical industry. The significance of aqueous two-phase systems (ATPSs) in downstream processing with commercial application has been reported for the separation of a large number of biopharmaceutical products. For both industrial- and laboratory-scale purposes it is essential to know the partitioning behaviour of biomolecules and which parameters lead to an optimal separation [1]. ATPS process design and implementation at a large scale is limited by the poor understanding of the molecular mechanism behind the solute partitioning. A better understanding of the molecular mechanism of the factors, which govern partitioning, contributes for the prediction of the partitioning behaviour in ATPSs. The approach is based on a thermodynamic cycle where the polar and nonpolar contributions to the free energy of transfer are assumed to be additive. The total free energy of transfer was experimentally obtained by determination of the proteins partitioning coefficient. Electrostatic energy contributions were estimated using a Poisson-Boltzmann computational method. The nonpolar contribution was obtained as a difference between the total free energy of transfer and the electrostatic contribution and related with the solvent accessible surface area. This methodology was already successfully applied to the partitioning of amino acids in ATPSs [2]. In this study partitioning of a 14 globular proteins, was examined in 4 different polymer/polymer ATPSs. The model performance was analysed regarding to the influence of different PDB structure and protein charges. Nonpolar energy contribution was related with the solvent accessible surface area, by linear relationship. Using a semi-empirical model, it was possible to predict the partition coefficient of several proteins in four different polymer/polymer systems. The model shows improved prediction capacity when applied to the group of protein with the same electrostatic characteristic (positive or negative charge proteins).","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"15 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":"117067705","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":"Medical thermal imaging procedure for HAVS assessment","authors":"R. Vardasca, J. Gabriel","doi":"10.1109/ENBENG.2015.7088806","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088806","url":null,"abstract":"Introduction: Hand Arm Vibration Syndrome (HAVS) is an occupational condition that affects subjects exposed to vibrating tools at the workplace and needs an accurate quantitative and objective diagnostic test to aid clinicians in the judgment of the degree of injury and adequate treatment. An objective assessing method is needed to provide a permanent evidence record of the degree of injury. In case of chronic or permanent injury an objective measure to specify an appropriate compensation is required. Methodology: Medical thermal imaging was used to monitor the hands exposed to an objective mechanical provocation test involving vertical vibration, for 2 minutes at 31.5Hz and 36 mm/s2. This test was followed by a thermal provocation challenge (CST) of the hand for a period of 1 minute at 20°C. Images were taken during the whole procedure. In order to assess the peripheral temperature changes of the dorsal hand, a computational model was developed and the images were standardized and analyzed. Results: It was possible to discriminate between controls and patients (p<;0.05) and to identify through medical thermal imaging the affected fingers and their temperature changes, assessing objectively the stage of the injury. Conclusion: The proposed methodology is objective and repeatable, providing important physiological information of the evolutionary stage of HAVS. Medical thermal imaging is advised as a complementary diagnostic method, providing permanent evidence of the condition in support to medical history in medico-legal liabilities.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"6 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":"115591417","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 web-based framework using a Model-View-Controller architecture for human motion analysis","authors":"Joana Rosa, Hugo Silva, R. Matias","doi":"10.1109/ENBENG.2015.7088815","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088815","url":null,"abstract":"In a world with large technological advances and where technology takes a more and more essential place, the interaction between technology and health is increasingly present, particularly when one speaks of web technologies. The computerized clinical decision support systems (CDDS) are a good example of combination of web technology and health [1]. This work was part of a larger project that aimed to develop a tractable cloud-based open-source framework for human movement analysis and classification, using inverse kinematics from marker trajectories collected by means of a motion capture system. The main objective of the present work was to contribute to the development of a web-based framework for human motion analysis, throughout an interface designed under a Model-View-Controller (MVC) architecture [2]. The communication between the client and the server is based on the HyperText Transfer Protocol (HTTP) and the WebSocket standard. HTML5 is the base technology, which controls the overall layout of the front-end (user interface). Together with this technology we used Impress.js, which controls the style and layout of the web page. For a high-performance back-end, we used the Python programming language, which was responsible for the connection between the user interface and the tools of the OpenSim software (Scale and IK), as well as all the data processing. Usability and learnability assessment was assessed using the System Usability Scale [3]. The target audience for this study was chosen from two groups, which are representative of the potential end-user populations: a) Biomedical engineering students; b) Clinicians and students of physiotherapy. None of the groups had previous knowledge with the system, and before the experience, the individuals of the each groups had a 4 minutes explanation on the interface of the features and way of using. Preliminary results shown usability scores comprised between 74,2 and 84,4 respectively for groups a) and b), and learnability scores of 67,9 and 78,6 respectively for groups a) and b). With the proposed framework the users can simply upload the patient's clinical information, determine how the selected musculoskeletal model anthropometry should be modified so it best matches patients characteristics, and to what degree each model's segment (markers) should match the collected motion data during the inverse kinematics process. Finally a report is generated, where it is possible to observe a given variable, a group of variables compare, experimental and normative data, and also add comments, print, and save it in PDF. From SUS results we conclude that the interface was extremely useful, clear, and easy-to-use and learn for both groups. Also, the users are likely to recommend our framework to other.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"48 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":"121910926","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":"Electrospun mats of biodegradable chitosan-based polyurethane urea","authors":"T. Vieira, J. Borges, C. Henriques","doi":"10.1109/ENBENG.2015.7088811","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088811","url":null,"abstract":"Polyurethane ureas (PUU) are segmented polymers where soft and hard segments are separated in microphases. Usually, the soft segment is derived from a polyol and the hard segment from a diisocyanate and a chain extender. The PUU properties can be tuned in order to obtain biodegradable scaffolds with suitable mechanical properties for tissue engineering applications [1]. Electrospinning is a convenient technique for the production of nanofibrous scaffolds from a polymeric solution that mimic the extracellular matrix, thereby supporting cell attachment and growth [2]. The physico-chemical properties of the material used and the scaffold's architecture both provide cells with cues. In this work, we synthetized a PUU based on PCL-diol using CS as chain extender (PUU-CS) [3]. Molecular structure was analyzed by 1H NMR and FTIR. Thermogravimetric analysis was performed to examine the thermal stability. The PUU-CS was electrospun from solutions using a mixture of tetrahydrofuran and N, N-dimethylformamide as solvent. Randomly oriented and aligned fibres were collected on a static and on a rotating collector, respectively. Morphological properties were characterized by SEM and mechanical properties evaluated through tensile tests. Hydrolytic (phosphate buffer saline (PBS) solution) and enzymatic (lipase) degradation studies were carried out. The cytocompatibility of the PUU-CS fibre mats was evaluated using the extract method. A preliminary study of cell adhesion was also performed. Spectroscopic results confirmed that PUU-CS was successfully produced and is stable at least until 200 oC. Randomly oriented and aligned fibres with different mean diameters were obtained. Both types of fibre mats showed higher Young's modulus for the thinner fibres. Elongation at break was lower for the aligned fibre mats. No mass changes were observed in the mats during 3 months in PBS while significant degradation was observed in lipase. In vitro tests didn't demonstrate any toxicity of the extracts. Cells seeded on the mats were able to adhere. These properties make nanofiber mats based on PUU-CS good candidates for soft tissue engineering.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"3 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":"126479768","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":"Spatial monitoring of temperature estimation during ultrasound heating therapy","authors":"H. Simoes Duarte, A. Santos, M. Graca Ruano","doi":"10.1109/ENBENG.2015.7088891","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088891","url":null,"abstract":"Ultrasound instrumentation is being increasingly used for therapeutic purposes but its usage for heating treatments still requires more investigation in terms of spatial-temporal characterization of induced tissue's temperature. Non-invasive ultrasound temperature estimation is accepted to be well performed when based on ultrasound imaging's temporal eco-shifts calculations. Present paper reports experiments developed to analyze temperature propagation on a plane parallel to the heating transducer's face, enlarging as so the spatial range previously tested. Relationship between the reference and the echo delayed signals between pairs of spatial locations symmetrically located in regard to the heating transducer's face have been analyzed in detail. Results demonstrate that ultrasound heating transducer should not be assumed to produce symmetrical pressure field patterns, and, more relevant, that the frequently used temporal eco-shift algorithm do not produce precise estimations of temperature in spatial locations above the axial line of the heating transducer's face towards the imaging transducer.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"36 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":"114692248","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":"Diffusional kurtosis imaging using a fast heuristic constrained linear least squares algorithm: A plugin for OsiriX","authors":"N. Mesquita, J. Santinha, Jose Fonseca","doi":"10.1109/ENBENG.2015.7088874","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088874","url":null,"abstract":"A new easy-to-use and multivendor tool for diffusion kurtosis imaging is presented, which, given a series of diffusion weighted images (DWI's), generates maps for Mean Diffusion, Axial Diffusion, Radial Diffusion, Fractional Anisotropy, Mean Kurtosis, Axial Kurtosis and Radial Kurtosis, using a heuristic constrained linear least squares algorithm proposed by (Tabesh et al. 2011). The tool was developed as a plugin for OsiriX, an open-source PACS workstation and medical image processing tool, to assist medical imaging research. The preliminary results obtained with the developed plugin are subject to both qualitative and quantitative validations with promising results. Nevertheless, thorough validation is necessary before making this plugin available for medical research.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"6 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":"131605721","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":"Robotic locomotion combining Central Pattern Generators and reflexes","authors":"C. Ferreira, C. Santos","doi":"10.1109/ENBENG.2015.7088893","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088893","url":null,"abstract":"The development of bio-inspired controllers seems to be a good and robust way to obtain an efficient and robust robotic locomotion, mimicking their biological counterparts. In this Master Thesis two bio-inspired controllers were developed in order to generate stable and robust locomotion on uneven terrains. Firstly, a reflex controller that has to be capable of generating locomotion, based only on sensory information. Secondly, a hybrid controller that combines Central Pattern Generators (CPGs) and reflexes. The results show that the reflex controller is capable of producing stable quadruped locomotion with a regular stepping pattern, and it proved to be capable of dealing with slopes and small obstacles. The hybrid controller improved the robot's behavior by increasing its stability, harmony and displacement in the majority of the experiments. Moreover, the stepping patterns become more regular. This combination enables to increase robustness to sensor imperfections and to anticipate the robot's motor actions.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"11 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":"131979828","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 serious game for rehabilitation of neurological disabilities: Premilinary study","authors":"T. Martins, V. Carvalho, F. Soares","doi":"10.1109/ENBENG.2015.7088843","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088843","url":null,"abstract":"Usually the exercises defined in the physical therapy programs for patients with motor disabilities as a result of neurological disease are repetitive and boring. The design and implementation of pleasant environments and contexts to motivate the patients to continue their treatment are needed. Serious games appear as a suitable solution. Therefore, the development of a serious game for physiotherapy and monitoring of people with motor disabilities using image processing techniques is presented.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"41 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":"124304680","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":"Zinc changes evoked by phenolic compounds and effect on TEA-LTP at hippocampal mossy fiber synapses","authors":"Fatima C. Bastos, Sandra A. Lopes, Vanessa N. Corceiro, J. Dionísio, C. Matias, P. J. Mendes, F. S. D. Sampaio dos Aidos, R. Quinta-Ferreira, M. Quinta-Ferreira","doi":"10.1109/ENBENG.2015.7088873","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088873","url":null,"abstract":"The analysis of phenolic compounds pollution on health is a topic of major concern, in particular the effects associated with cellular damages. In central nervous system zinc can be either a neuromodulator or a neurotoxin, depending on the intracellular concentration and may be implicated in various neurodegenerative diseases. This work focused on the influence of phenolic pollutants on postsynaptic zinc changes, including during chemically induced long term potentiation (LTP). The study was performed in hippocampal slices from Wistar rats at the zinc-rich mossy fiber synapses. Zinc changes were detected by means of the permeant fluorescent zinc probe Newport Green. A mixture of six phenolic pollutants caused a reversible enhancement of zinc signals, indicating that those compounds cause zinc entry into neurons. The action of the phenolic compounds was also evaluated on zinc changes associated with TEA induced LTP. It was found that the zinc signals decreased in a reversible way in the presence of TEA, as observed in control experiments. This reduction may be due to the activation of presynaptic KATP channels, suggesting that mossy fiber TEA-LTP is not significantly affected by the pollutants.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"36 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":"129247087","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":"Screening of L-histidine based ligands to purify the supercoiled plasmid DNA isoform","authors":"Lúcia F. A. Amorim, F. Sousa, J. Queiroz, C. Cruz, Â. Sousa","doi":"10.1109/ENBENG.2015.7088829","DOIUrl":"https://doi.org/10.1109/ENBENG.2015.7088829","url":null,"abstract":"Summary form only given. Cervical cancer and high risk human papillomavirus (HPV) are highly associated and currently, the preventive vaccines only induce the antibody immunity. The urge to attenuate lesions and tumour progressions led to development of DNA vaccines, able to induce both humoural and cellular immune responses. Plasmid DNA (pDNA) is being widely explored as a non-viral vector due to its lack of toxicity, low cost manufacture and high expression levels. To produce an effective pDNA vaccine, a biotechnology platform is required and every single step has to be optimized in order to obtain this molecule with high purity degree, able to efficiently transfect eukaryotic cells with satisfactory expression of the target gene. Amino acid-affinity chromatography has been considered a promissory approach that selectively recognizes the biologically active pDNA topology, the supercoiled (sc) isoform. Thus, the aim of this work was to perform a screening of L-histidine-based amino acids employing the surface plasmon resonance (SPR) technique in order to modify a monolithic support with the suitable ligand for sc pDNA purification. Several experiments were performed with three plasmids of different sizes (6.05, 8.70 and 14 Kbp) and different isoforms (open circular, sc and linear), separately. The SPR results revealed that the overall affinity of plasmids to L-histidine-based ligands was high (KD >10-8 M) and the highest affinity was found for HPV-16 E6/E7. Therefore, L-histidine and 1-benzyl-L-histidine ligands were immobilized on epoxy monoliths and several chromatographic studies were accomplished with the aforementioned samples. In general, the sc isoform developed strong interactions with the modified supports and the separation of plasmid isoforms was achieved by decreasing the ammonium sulfate concentration. Lower salt content was required in the 1-benzyl-L-histidine monolith because of stronger interactions promoted with pDNA. The separation of plasmid isoforms remained unchanged by flow rate variations. The breakthrough experiments of L-histidine monolith revealed satisfactory dynamic binding capacity when compared to other matrices [1]. Overall, purification methodologies can benefit from affinity analysis provided by SPR biosensor. The combination of L-histidine and 1-benzyl-L-histine ligands with monolithic supports can be a promising strategy to purify the sc pDNA with the desirable purity degree for pharmaceutical applications, such as DNA vaccines.","PeriodicalId":285567,"journal":{"name":"2015 IEEE 4th Portuguese Meeting on Bioengineering (ENBENG)","volume":"4 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":"128514544","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}