Mexican Journal of Biomedical Engineering <center> <div class="page" title="Page 1"> <div class="layoutArea"> <div class="column"> <p>Call for Papers for Special Issue on “Biomedical Engineering Innovations for Coronavirus COVID-19”</p> </div> </div> </div> <p><a href="Call%20for Papers for Special Issue on “Biomedical Engineering Innovations for Coronavirus COVID-19”"><strong>DOWNLOAD FULL INFO HERE</strong></a></p> <p><strong>MISSION</strong></p> <p align="left"><em>La Revista Mexicana de Ingeniería Biomédica</em> (The Mexican Journal of Biomedical Engineering, RMIB, for its Spanish acronym) is a publication oriented to the dissemination of papers of the Mexican and international scientific community whose lines of research are aligned to the improvement of the quality of life through engineering techniques.</p> <p align="left">The papers that are considered for being published in the RMIB must be original, unpublished, and first rate, and they can cover the areas of Medical Instrumentation, Biomedical Signals, Medical Information Technology, Biomaterials, Clinical Engineering, Physiological Models, and Medical Imaging as well as lines of research related to various branches of engineering applied to the health sciences.</p> <p align="left">The RMIB is an electronic journal published quarterly ( January, May, September) by the Mexican Society of Biomedical Engineering,&nbsp; founded since 1980. It publishes articles in spanish and english and is aimed at academics, researchers and professionals interested in the subspecialties of Biomedical Engineering.</p> <p><strong>INDEXES</strong></p> <p><em>La revista Mexicana de Ingeniería Biomédica</em> is a quarterly publication, and it is found in the following indexes:</p> <p>&nbsp;<img src="/public/site/images/administrador/21.jpg" alt="" width="780" height="110"><img src="/public/site/images/administrador/1.jpg" alt="" width="780" height="110"><img src="/public/site/images/administrador/4.jpg" alt="" width="780" height="110"></p> <p><img src="/public/site/images/administrador/Unknown1.png" alt=""></p> </center> Sociedad Mexicana de Ingeniería Biomédica en-US Mexican Journal of Biomedical Engineering 0188-9532 <p>Upon acceptance of an article in the RMIB, corresponding authors will be asked to fulfill and sign the copyright and the journal publishing agreement, which will allow the RMIB authorization to publish this document in any media without limitations and without any cost. Authors may reuse parts of the paper in other documents and reproduce part or all of it for their personal use as long as a bibliographic reference is made to the RMIB and a copy of the reference is sent. However written permission of the Publisher is required for resale or distribution outside the corresponding author institution and for all other derivative works, including compilations and translations.</p> <p>&nbsp;</p> Determination of early bone metastasis on Bone Scans Using the Gray Levels Histogram <p>The aim of this paper is to show a technique to speed up the interpretation of bone scans in order to determine the presence of early bone metastasis. This is done using the gray levels histogram of the region of interest. The technique is intended to assist in the bone scans interpretation in order to provide a successful diagnosis. During the analysis, three types of histograms were observed on the regions of interest. If the histogram is narrow and shifted toward the origin, the bone scan is free of metastasis.&nbsp; If it is shifted to the right and slightly broadened, indicates the presence of a bone anomaly different from a metastasis. On the other hand, if the histogram is more broadened and shifted to the right, is suggests the presence of metastasis. This histogram is characterized by displaying small curls on the right side providing information about the metastatic disease stage, which could be low-amplitude peaks and have a short length, if the metastasis is in early stage, or high-amplitude peaks and a long length, if is advanced.&nbsp; Finally, the analyzed region is displayed in false color considering the minimum gray levels observed in the histogram.</p> Mónica Pérez Meza Alberto Jaramillo Núñez Bolivia Cuevas Otahola Jesús Alonso Arriaga Hernández Bárbara Emma Sánchez Rinza Copyright (c) 2021 Mónica Pérez Meza, Alberto Jaramillo Núñez, Bolivia Cuevas Otahola, Jesús Alonso Arriaga Hernández, Bárbara Emma Sánchez Rinza 2021-02-14 2021-02-14 42 2 6 14 Theoretical Study of the Function of the IP3 Receptor / BK Channel Complex in a Single Neuron <p>Large conductance calcium-activated potassium (BK) channels carry out many functions in the central nervous system. The opening of BK channels requires a rise in the cytosolic calcium ([Ca<sup>2+</sup>]<sub>cyt</sub>) concentration, which can occur in two ways: calcium influx from voltage-gated calcium channels (VGCCs) located on the plasma membrane and calcium efflux through the endoplasmic reticulum (ER) membrane to the cytosol triggered by inositol 1,4,5-trisphosphate (IP<sub>3</sub>) receptors (IP<sub>3</sub>-Rs) and ryanodine receptors (RyRs). The BK channel/IP<sub>3</sub>-R/RyR interaction has been widely reported in smooth muscle but scarce information exist on neurons, where its presence is uncertain. The aim of this study was to develop a computational model of a neuron to replicate the interaction between the release of Ca<sup>2+</sup> from the ER (through IP<sub>3</sub>-Rs and RyRs) and the opening of BK channels on the plasma membrane to regulate the level of [Ca<sup>2+</sup>]<sub>cyt</sub>, based on the Hodgkin-Huxley formalism and the Goldbeter model. The mathematical models were implemented on Visual Basic® and differential equations were solved numerically. Various conditions of BK conductance and the efflux of endoplasmic Ca<sup>2+</sup> were explored. The results show that an abrupt increase in [Ca<sup>2+</sup>]<sub>cyt</sub> (≥ 5 mM) activates the BK channels and either pauses or stops the action potential train.</p> María Eugenia Pérez Bonilla Marleni Reyes Monreal Jessica Quintero Pérez Miguel Pérez Escalera Arturo Reyes Lazalde Copyright (c) 2021 María Eugenia Pérez Bonilla, Marleni Reyes Monreal, Jessica Quintero Pérez, Miguel Pérez Escalera, Arturo Reyes Lazalde 2021-03-01 2021-03-01 42 2 15 31 Antibacterial Activity Analysis of Hydroxyapatite Based Materials with Fluorine and Silver <p>This investigation aims to evaluate the antibacterial activity of nanostructured hydroxyapatite based materials doped with silver and fluorine, to be used as a biomaterial with antibacterial activity. Four different formulations were prepared by combustion method: hydroxyapatite, hydroxyapatite-fluorine, hydroxyapatite-silver-fluorine and hydroxyapatite-silver, with 2% of the doping agents. X-ray diffraction technique was used to determine the mineralogy, identifying the presence of Ca<sub>5</sub>(PO<sub>4</sub>)<sub>3</sub>OH, Ca<sub>2</sub>P<sub>2</sub>O<sub>7</sub>, Ag<sub>3</sub>PO<sub>4</sub>, AgCa<sub>10</sub>(PO<sub>4</sub>)<sub>7</sub> Ca<sub>5</sub>(PO<sub>4</sub>)<sub>3</sub>F and CaF<sub>2</sub> phases for the studied samples. Scanning electron microscopy was used to study the morphological structure and it showed homogeneous crystallization of the hydroxyapatite and the inclusion of dopant agents. The antibacterial activity was determined using a modified inhibition test zone to observe if the bacteria (<em>E. faecalis</em>) was susceptible to the antimicrobial agent by the appearance of the zone of inhibition on the agar plate. Both the hydroxyapatite-silver and the hydroxyapatite-silver-fluorine materials generated an inhibition zone. It was possible to determine the minimum inhibitory concentration needed to kill most viable organisms after 48 hours of incubation using the broth microdilution method, resulting in 75 µg/ml and 200 µg/ml for the hydroxyapatite-silver and the hydroxyapatite-silver-fluorine formulation, respectively. These materials could be used for the development of new biomaterials that can be used in dental applications.</p> Verónica González Torres Esteban Hernández Guevara Nydia Alejandra Castillo Martínez Martha Rosales Aguilar César Gerardo Díaz Trujillo Copyright (c) 2021 Verónica González Torres, Esteban Hernández Guevara, Nydia Alejandra Castillo Martínez, Martha Rosales Aguilar, César Gerardo Díaz Trujillo 2021-03-21 2021-03-21 42 2 49 57 Biomechanical Evaluation of Hemiarthroplasty in the First Proximal Phalanx. A Finite Element Study <p>Hallux rigidus produces a decrease in the dorsiflexion of the first metatarsophalangeal joint and is usually associated with the appearance of osteophytes. Hemiarthroplasty in the first proximal phalanx is a recommended surgical procedure in patients with advanced grade of hallux rigidus. Finite element analysis allows us to understand the biomechanical behavior of the foot. The objective of this work is to evaluate the biomechanical effects of an hemi implant placed in first proximal phalanx. Two models of finite elements are going to be compared, one free of pathologies and the other with a hemiarthroplasty in the first ray of the foot. We detected after inserting the prosthesis in the model that passive windlass mechanism is lost, and the lesser toes become overloaded, which leads to a loss of efficiency in gait as well as being able to cause postsurgical medical complications.</p> Mario Alberto Madrid Pérez Ricardo Becerro de Bengoa Vallejo Javier Bayod López Copyright (c) 2021 Mario Alberto Madrid Pérez, Ricardo Becerro de Bengoa Vallejo, Javier Bayod López 2021-04-21 2021-04-21 42 2 58 66 Detection of Exudates and Microaneurysms in the Retina by Segmentation in Fundus Images <p>This article proposes two methodologies for the detection of lesions in the retina, which may indicate the presence of diabetic retinopathy (DR). Through the use of digital image processing techniques, it is possible to isolate the pixels that correspond to a lesion of RD, to achieve segmenting microaneurysms, the edges of the objects contained in the image are highlighted in order to detect the contours of the objects to select by size those that meet an area of 15 to 25 pixels in the case of 512x512 images and identify the objects as possible microaneurysms, while for the detection of exudates the green channel is selected to contrast the luminous objects in the retinography and from the conversion to gray scale, a histogram is graphed to identify the ideal threshold for the segmentation of the pixels that belong to the exudates at the end of the optical disk previously identified by a specialist. A confusion matrix supervised by an ophthalmologist was created to quantify the results obtained by the two methodologies, obtaining a specificity of 0.94 and a sensitivity of 0.97, values that are outstanding to proceed with the classification stage.</p> Eduardo Bernal Catalán Eduardo De la Cruz Gámez José Antonio Montero Valverde Rafael Hernández Reyna José Luis Hernández Hernández Copyright (c) 2021 Eduardo Bernal Catalán, Eduardo De la Cruz Gámez, José Antonio Montero Valverde, Rafael Hernández Reyna, José Luis Hernández Hernández 2021-05-20 2021-05-20 42 2 67 77 Feature Extraction from Distributions of Phase Synchronization Values of EEG Recordings <p>Epilepsy is the most common neurological pathology. Despite treatments available to patients only 58% to 73% will be free of seizures. This uncertainty of the treatment’s outcome is the basis of other psychiatric affections to patients who are uncertain of the success of their treatment. Seizure prediction models (SPMs) emerged as an aid to help the patient know if he is susceptible to an imminent crisis; such models are based of continuous monitoring of EEG signals of the patient and subsequent continuous analysis of those signals. Looking for features in the signals which differentiate ictal from interictal is an ongoing field of research which aims to get a robust set of features to feed the SPM and get a high degree of certainty of when the next seizure will occur. In this work we propose the analysis of phase differences of EEG as a method to extract features which are able to discriminate between ictal and preictal states of a patient, in specific the numeric distance between q1 and q3 of the distribution of phase differences, We compare this values with other phase synchronization methods and test our hypothesis getting a p = &nbsp;0.0001 with our proposed method.</p> Jaime Arturo Quirarte Tejeda Jorge Luis Flores Nuñez Rebeca Romo Vázquez Copyright (c) 2021 Jaime Arturo Quirarte Tejeda , Jorge Luis Flores Nuñez, Rebeca Romo 2021-06-07 2021-06-07 42 2 78 89 Three-dimensional printing in healthcare <p>This work aims to briefly present the cutting edge of 3D printing innovation in healthcare. This technology is used for surgical planning, medical education, bioprinting of tissues, and medical equipment spare parts in fields like pharmacology, prosthetics, surgery, and regenerative medicine. A review of the last decade was made in the search engines of PubMed and Espacenet. Three authors reviewed titles, abstracts, and keywords separately to identify studies appropriate to the topic. After the initial examination, complete texts of identified relevant studies were obtained and classified according to the authors. Results were synthesized in a narrative literature review. The revision showed that 3D printing has become of common use in the healthcare system since it allows medical personnel to implement customized solutions for each patient, thus reducing the probability of a false diagnostic or treatment. Major applications among the advantages and disadvantages of 3D printing in healthcare were presented. Nowadays, the main challenge in 3D printing is the cost of the equipment and its manufacturing. In the future, the challenges in cost could be reduced, but processing requirements and limited materials may still need further work.</p> Alberto Isaac Pérez Sanpablo Elisa Romero Avila Arturo González Mendoza Copyright (c) 2021 Alberto Isaac Pérez Sanpablo, Elisa Romero Avila, Arturo González Mendoza 2021-03-21 2021-03-21 42 2 32 48