فهرست مطالب

Medical Signals and Sensors - Volume:9 Issue:3, 2019
  • Volume:9 Issue:3, 2019
  • تاریخ انتشار: 1398/07/01
  • تعداد عناوین: 8
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  • Zahra Khodabandeh, Hossein Rabbani, Alireza Mehri Dehnavi*, Omid Sarrafzadeh Pages 145-157
    Background

    A fair amount of important objects in natural images have circular and elliptical shapes. For example, the nucleus of most of the biological cells is circular, and a number of parasites such as Oxyuris have elliptical shapes in microscopic images. Hence, atomic representations by two-dimensional (2D) basis functions based on circle and ellipse can be useful for processing these images. The first researches have been done in this domain by introducing circlet transform.

    Methods

    The main goal of this article is expanding the circlet to a new one with elliptical basis functions.

    Results

    In this article, we first introduce a new transform called ellipselet and then compare it with other X-let transforms including 2D-discrete wavelet transform, dual-tree complex wavelet, curvelet, contourlet, steerable pyramid, and circlet transform in the application of image denoising.

    Conclusion

    Experimental results show that for noises under 30, the ellipselet is better than other geometrical X-lets in terms of Peak Signal to Noise Ratio, especially for Lena which contains more circular structures. However, for Barbara which has fine structures in its texture, it has worse results than dual-tree complex wavelet and steerable pyramid.

    Keywords: Basis functions, circlet, ellipselet, image denoising, X-lets
  • Suryani Dyah Astuti*, Yanuar Mukhammad, Sirlus Andreanto Jasman Duli, Alfian Pramudita Putra, Ernie Maduratna Setiawatie, Kuwat Triyana Pages 158-164
    Background

    Gas sensor array system is a device that mimics the work of how the nose smells using the gas sensors that could give response toward specific odors. It is used for characterizing the different blended gas that is suited with the biological working nose principle. Thus, it could be used to detect the dental and oral diseases. Periodontitis is one of the diseases caused by the damage on the teeth due to the chronic infection on the gingival structure marked with bacterial plaque and calculus. This study aims to develop an electric nose for odor detection application on the periodontal bacterial biofilm as early detection device for dental and oral disease.

    Methods

    This device is designed as a portable device to ease the data acquisition. The measured data were stored at a database system connected to a real-time computer. A gas array sensor system with six gas sensors (TGS 826, TGS 2602, TGS 2600, TGS 2611, TGS 2612, and TGS 2620) has been assembled for the early detection application for dental and oral disease excreted by the bacterial biofilm that caused dental and oral disease, including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans, and Enterococcus faecalis.

    Results

    TGS 826 and TGS 2602 sensor had the best response showed by the high ADC delta value.

    Conclusion

    GS 826 and TGS 2602 sensor could be used as a candidate for early detection device for dental and oral disease.

    Keywords: Bacterial biofilm, gas array sensor system, gas sensor, TGS 826, TGS 2602 sensor
  • Alireza Shirani*, Mohammadreza Sehhati Pages 165-173
    Background

    Automatic vehicle location (AVL) refers to a system that calculates the geographical location of any vehicle, i.e., latitude and longitude. Vehicle location information about one or more moving vehicles can be stored in the internal memory and accessed when vehicles are available (offline tracking). It is also possible to get location information on a real-time basis (online tracking). The real-time tracking systems designed to date may incorporate three devices: global positioning system (GPS), geographic information system, and cellular communication platforms that may be either a general packet radio service (GPRS) or any private and local radiofrequency network.

    Methods

    The GPS based navigation system has been designed so as to allow for user-friendly real-time tracking applications for any emergency vehicles like ambulances. First, GPS coordinates are obtained from the SIM908 module and sent via to a server transmission control protocol/internet protocol. Server codes, which are written in C#, load Google map to show real-time location.

    Results

    We designed online tracking AVL hardware in the two simple and advanced versions. The latter enables both the ambulance driver and the data center to monitor path real-time besides enabling the vehicle driver to receive and make calls and send or receive messages. The former only sends latitude and longitude to the data server continuously, and the path travelled by vehicle is displayed.

    Conclusion

    SIM908 integrates GSM, GPRS, and GPS in one package. It can be a proper choice for real-time economic tracking systems despite its low accuracy in finding geolocations.

    Keywords: Automatic vehicle location, general packet radio service, geographic information system, global positioning system, Google map, latitude, longitude, transmission control protocol, internet protocol, vehicle tracking
  • Monire Khayamnia*, Mohammadreza Yazdchi, Aghile Heidari, Mohsen Foroughipour Pages 174-180
    Background

    Headache is one of the most common forms of medical complaints with numerous underlying causes and many patterns of presentation. The first step for starting the treatment is the recognition stage. In this article, the problem of primary and secondary headache diagnosis is considered, and we evaluate the use of intelligence techniques and soft computing in order to predict the diagnosis of common headaches.

    Methods

    A fuzzy expert-based system for the diagnosis of common headaches by Learning-From-Examples (LFE) algorithm is presented, in which Mamdani model was used in fuzzy inference engine using Max-Min as Or-And operators, and the Centroid method was used as defuzzification technique. In addition, this article has analyzed common headache using two classification techniques, and headache diagnosis based on a support vector machine (SVM) and multilayer perceptron (MLP)-based method has been proposed. The classifiers were used to recognize the four types of common headache, namely migraine, tension, headaches as a result of infection, and headaches as a result of increased intra cranial presser.

    Results

    By using a dataset obtained from 190 patients, suffering from primary and secondary headaches, who were enrolled from a medical center located in Mashhad, the diagnostic fuzzy system was trained by LFE algorithm, and on an average, 123 pieces of If-Then rules were produced for fuzzy system, and it was observed that the system had the ability of correct recognition by a rate of 85%. Using the headache diagnostic system by MLP- and SVM-based decision support system, the accuracy of classification into four types improved by 88% when using the MLP and by 90% with the SVM classifier. The performance of all methods is evaluated using classification accuracy, precision, sensitivity, and specificity.

    Conclusion

    As the linguistic rules may be incomplete when human experts express their knowledge, and according to the proximity of common headache symptoms and importance of early diagnosis, the LFE training algorithm is more effective than human expert system. Favorable results obtained by the implementation and evaluation of the suggested medical decision support system based on the MLP and SVM show that intelligence techniques can be very useful for the recognition of common headaches with similar symptoms.

    Keywords: Headache, Learning-From-Example algorithm, multilayer perceptron, recognition, support vector machines
  • Seyed Mohammad Zargar, Darioush Khodabakhshi Hafshejani, Asghar Eskandarinia, Mohammad Rafienia, Anousheh Zargar Kharazi* Pages 181-189

    Novel drug delivery systems have ameliorated drugs' pharmacokinetics and declined undesired ramifications while led to a better patient compliance by extending the time of release. In fact, although there has been a multitude of encouraging achievements in controlled drug release, the application of micro- and nano-carriers is confronted with some challenges such as rapid clearance and inefficient targeting. In addition, since cell systems can be an appropriate alternative to micro- and nano-particles, they have been used as biological carriers. In general, features such as stable release into blood, slow clearance, efficient targeting, and high biocompatibility are the main properties of cells applied as drug carriers. Furthermore, some cells such as erythrocytes, leukocytes, stem cells, and platelets have been used as release systems. Hence, most common cells that were used as aforementioned release systems are going to be presented in this review article.

    Keywords: Drug delivery, erythrocytes, macrophages, platelets, stem cells
  • Asghar Maziar*, Reza Paydar, Ghazal Azadbakht, Daryoush Shahbazi Gahrouei Pages 190-195

    Thyroid exposure to radiation in brain computed tomography (CT) scan is of great value since it is considered as a vital organ. This study aimed to investigate the absorbed dose of thyroid by various protocols of head CT in patients referring to 64-slice CT scan center and to compare the values with the calculated dose by imaging performance and assessment of CT (ImPACT) method. Also, the values of CT scan dose index (CTDI) were calculated with semiconductor detector. In this cross-sectional study, 120 outpatients including three groups of forty individuals over 40 years old referring to the hospital radiology centers in Tehran for head CT were chosen and 3 thermo-luminescence dosimeter (TLD-GR200) were applied on thyroid gland of each patient. For brain CT, Absorbed and effective doses of thyroid gland were calculated by ImPACT software. In addition, semiconductor detector in head CTDI phantom calculated CTDI for the applied protocols. Mean effective dose of thyroid gland in brain scan group was calculated by TLD and ImPACT software which showed no significant difference (P < 0.001). Mean effective dose of thyroid gland in unidirectional and bi-directional sinus scan by TLD and ImPACT software were different significantly (P < 0.001). Also, the differences between CTDI values shown by brain and sinus scan protocol with semiconductor detector and those CTDI were significant (P < 0.001). The calculated values of absorbed dose and effective doses of thyroid by TLD and ImPACT software were not significantly different. Mean effective dose calculated for thyroid gland in head scans by TLD and ImPACT was less than the annual permissive level for thyroid gland suggested by International Committee on Radiological Protection. In this study, calculated values of thyroid effective dose in brain scan with 64-slice scanner were less than the calculated values in a similar study.

    Keywords: 64-slice computed tomography, absorbed dose, computed tomography scan dose index, dose calculation, thermoluminescent dosimeter, thyroid cancer
  • Raziyeh Mazrouei, Elham Raeisi, Yves Lemoigne, Esfandiar Heidarian* Pages 196-203

    One of the most common malignancies in women is breast cancer. B-escin has pharmacological anticancer effects. 5-fluorouracil (5-FU) has antimetabolite and antiproliferative properties. The purpose of this study was to investigate the combined effects of 5-FU and B-escin on apoptosis, colony formation, Bcl-2 signaling protein, and p53 gene expression in MCF7 breast cancer cell line. The cytotoxic effects, the number of colonies, apoptosis, p53 gene expression, and Bcl-2 signaling protein of the combined 5-FU and B-escin on MCF7 cells were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, clonogenic assay, flow cytometry, real-time quantitative polymerase chain reaction, and western blotting methods, respectively. Half-maximal inhibitory concentration values of B-escin and 5-FU were 80 Micro g/ml and 2 Micro M, respectively. The combination of 5-FU and B-escin on MCF7 cell viability showed a combination index equal to 0.5. The expression of p53 and apoptosis increased in the combination of 5-FU and B-escin on MCF7 cells compared to that of control group (P < 0.05). In addition, the number of colonies and Bcl-2 signaling protein in combination of 5-FU and B-escin decreased with respect to untreated control cells or single treatment of 5-FU and B-escin. The combination of 5-FU and B-escin not only has synergistic effects by increasing cell apoptosis and p53 gene expression but also decreases Bcl-2 signaling protein in MCF7 cell lines.

    Keywords: 5-fluorouracil, apoptosis, MCF7, p53, B-escin
  • Gholamreza Ataei, Maral Rezaei, Kourosh Ebrahimnejad Gorji, Amin Banaei, Nouraddin Abdi Goushbolagh, Bagher Farhood, Mahmoud Bagheri, Razzagh Abedi Firouzjah* Pages 204-210

    Gafchromic films are utilized for two-dimensional dose distribution measurements, especially in radiotherapy. In this study, we investigated a close connection between energy and dose rate of Gafchromic EBT3 films irradiating with 6 MV and Co-60 photon beams over a broad dose range. EBT3 films were exposed to 6 MV and Co-60 photon beams using 4 and 2 Gy/min dose rates over a 10-400 cGy dose range. The films were scanned in red, green, and blue channels to obtain the optical density (OD)-dose curves. The OD-dose curves resulted from three-color scans for different photon energies and dose rates were compared by statistical independent t-test. For the radiations of Co-60 and 6 MV photon beams, the highest correlation was obtained between the 2 and 4 Gy/min dose rates with red and green channels, respectively. Moreover, the red channel had a greater OD response per dose value, following the green and blue channels. There was no significant difference between different photon energies' (Co-60 and 6 MV) and dose rates' (2 and 4 Gy/min) dependence on OD-dose response of EBT3 films over a broad domain of radiation dose, except for different photon energies in the blue channel. Our results revealed that the OD-dose response of EBT3 films is independent on photon energies (Co-60 and 6 MV) and dose rate (2 and 4 Gy/min) in the evaluated dose range (10-400 cGy). Therefore, the EBT3 films are suitable, consistent, and reliable instruments for dose measurements in radiotherapy.

    Keywords: Dose rate response, dosimetry, EBT3 films, energy dependence, radiotherapy