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1.
Braz. arch. biol. technol ; 64: e21200301, 2021. tab, graf
Article in English | LILACS | ID: biblio-1278443

ABSTRACT

Abstract Rhamnolipid is a potent biodegradable surfactant, which frequently used in pharmaceutical and environmental industries, such as enhanced oil recovery and bioremediation. This study aims to engineer Escherichia coli for the heterologous host production of rhamnolipid, to characterize the rhamnolipid product, and to optimize the production using autoinduction medium and POME (palm oil mill effluent). The construction of genes involved in rhamnolipid biosynthesis was designed in two plasmids, pPM RHLAB (mono-rhamnolipid production plasmid) and pPM RHLABC (di-rhamnolipid production plasmid). The characterization of rhamnolipid congeners and activity using high-resolution mass spectrometry (HRMS) and critical micelle concentration (CMC). In order to estimate rhamnolipid yield, an oil spreading test was performed. HRMS and CMC result show E. coli pPM RHLAB mainly produced mono-rhamnolipid (Rha-C14:2) with 900 mg/L and 35.4 mN/m of CMC and surface tension value, whereas E. coli pPM RHLABC mainly produced di-rhamnolipid (Rha-Rha-C10) with 300 mg/L and 34.3 mN/m of CMC and surface tension value, respectively. The optimum condition to produce rhamnolipid was at 20 h cultivation time, 37 oC, and pH 7. In this condition, the maximum rhamnolipid yield of 1245.68 mg/L using autoinduction medium and 318.42 mg/L using 20% (v/v) of POME. In conclusion, the characteristics of the rhamnolipid by recombinant E. coli is very promising to be used in industries as the most economical way of producing rhamnolipid.


Subject(s)
Palm Oil , Escherichia coli , Electromagnetic Phenomena , Glycosylation
2.
Int. j. morphol ; 38(4): 983-989, Aug. 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1124886

ABSTRACT

Las articulaciones temporomandibulares y la musculatura asociada, permiten que la mandíbula se desplace en los tres planos del espacio (sagital, frontal y horizontal), de esta forma la mandíbula puede realizar movimientos mandibulares complejos. Hace varias décadas que los movimientos bordeantes mandibulares son estudiados, sin embargo, en un principio los estudios se realizaban en dos dimensiones (2D). En la actualidad, gracias al articulógrafo electromagnético (EMA) 3D es posible realizar el estudio de la cinemática mandibular en tres dimensiones (3D). El objetivo del siguiente estudio es analizar los movimientos mandibulares bordeantes (sagital, frontal y horizontal), por medio de la articulografía electromagnética 3D. En el estudio, participaron 11 personas de 31,9 ± 5,7 años en promedio (mujeres 30,2 ± 2,9 y hombres 34,0 ± 7,8) completamente dentados de primer molar a primer molar, sin trastornos temporomandibulares ni tratamiento previo de ortodoncia. Los archivos fueron procesados mediante scripts, desarrolladas en MATLAB®. Entre los resultados más relevantes, se encontró diferencia estadística entre hombres y mujeres en relación al área Frontal del polígono de Posselt, y los resultados del área del polígono sagital de todos los participantes, fue mayor que en estudios previos.


The temporomandibular joints and associated muscles allow the mandible to move in the three planes (sagittal, frontal and horizontal), in this way the jaw can perform complex mandibular movements. For several decades, mandibular border movements have been studied. However, studies were initially carried out in two dimensions (2D). At the present time, it is possible to analyze mandibular kinematics in three dimensions (3D), with the 3D electromagnetic articulograph (EMA). The objective of the study is to evaluate the mandibular border movements (sagittal, frontal and horizontal), using 3D electromagnetic articulation. In this analysis, 11 subjects 31.9 ± 5.7 years of age on average, participated (women 30.2 ± 2.9 and men 34.0 ± 7.8) completely dentate patients, from first to first molar, with no temporomandibular disorders or orthodontic pretreatment. Files were processed using scripts, developed in MATLAB®. Among the most relevant results, a statistical difference was found between men and women in relation to the Frontal area of Posselt polygon, and results of the sagittal polygon area of all the participants were greater than those reported in previous studies.


Subject(s)
Humans , Male , Female , Adult , Denture, Complete , Mandible/diagnostic imaging , Temporomandibular Joint , Biomechanical Phenomena , Sex Factors , Electromagnetic Phenomena , Mandible/physiology , Movement/physiology
3.
Int. j. odontostomatol. (Print) ; 14(2): 205-212, June 2020. tab, graf
Article in English | LILACS | ID: biblio-1090676

ABSTRACT

Mapudungun is a language used by Mapuche people in some regions of Chile and Argentina. The aim of this study was to describe the vowel phonemes with regard to the articulatory parameters (position of the tongue with respect to the palate and jaw opening) and acoustic parameters (f0, F1, F2 and F3) in Mapudungun speakers in the Region of La Araucanía. The vocalic phonemes of Mapudungun are six, where the first five are similar to those used in Spanish (/a e i o u/), to which is added a sixth vowel (/ɨ/) with its vocalic allophones (/ɨ/) and [Ә]. Three Mapudungun speakers were evaluated. The tongue movements were collected by Electromagnetic Articulography 3D and the data were processed with MATLAB and PRAAT software. It was possible to describe the trajectory of each third of the tongue during the production of the vowels. It was observed that the sixth vowel /Ә/ had minimal jaw opening during its pronunciation. In addition, the characteristic of /Ә/ as an unrounded mid-central vowel was corroborated. In this study, the tongue of mapudungun speakers was in a more posterior position than the found in other studies.


El Mapudungun es un lenguaje utilizado por los mapuches en algunas regiones de Chile y Argentina. El objetivo de este estudio fue describir los fonemas vocálicos respecto a los parámetros articulatorios (posición de la lengua respecto al paladar y apertura mandibular) y los parámetros acústicos (f0, F1, F2 y F3) en hablantes de Mapudungun en la Región de La Araucanía, los fonemas vocálicos de Mapudungun son seis, donde los primeros cinco son similares a los utilizados en español (/a e i o u /), a los que se agrega una sexta vocal (/ɨ/) con sus alófonos vocálicos [ɨ] y [Ә]. Se evaluaron tres hablantes de Mapudungun. Los movimientos de la lengua fueron registrados por Articulografía Electromagnética 3D y los datos fueron procesados con el software MATLAB y PRAAT. Fue posible describir la trayectoria de cada tercio de la lengua durante la producción de las vocales. Se observó que la sexta vocal /Ә/ tenía una apertura mínima de la mandíbula durante su pronunciación. Además, se corroboró la característica de /Ә/ como vocal central media no redondeada. En este estudio, la lengua de los hablantes de mapudungun estaba en una posición más posterior que la encontrada en otros estudios.


Subject(s)
Humans , Male , Female , Adult , Speech Production Measurement/instrumentation , Tongue/physiology , Phonetics , Indians, South American , Jaw/physiology , Speech Acoustics , Pilot Projects , Electromagnetic Phenomena
4.
Int. j. odontostomatol. (Print) ; 14(2): 198-204, June 2020. tab, graf
Article in Spanish | LILACS | ID: biblio-1090675

ABSTRACT

La masticación se ha estudiado desde diferentes puntos de vista, utilizando alimentos de prueba naturales y artificiales. La evidencia es escasa cuando se analizan alimentos a base de cereales, que van desde cereales para el desayuno hasta barras de granola. El investigar este tipo de alimentos, se vuelve importante para entender el comportamiento de la masticación frente a alimentos con diferentes composiciones y texturas, y como estas características pueden influir en el proceso masticatorio. Se analizó la masticación desde un punto de vista cinemático, en sujetos jóvenes dentados. El alimento de prueba utilizado fue granola prototipo y maní, este último se ha estudiado en sujetos con rehabilitación protésica y su consumo se recomienda en esta población. Se analizaron las características cinemáticas de la masticación como numero de ciclos, frecuencia masticatoria, velocidad de masticación de ascenso y descenso, y el área de masticación en los tres planos del espacio. Se relacionaron los movimientos masticatorios con los movimientos mandibulares bordeantes que conformaron el polígono de Posselt, este también se analizó en los tres planos espaciales. En todas las variables analizadas la granola presento valores mayores, excepto en el número de ciclos masticatorios, sólo se encontraron diferencias estadísticamente significativas (p= 0,03) al comparar la velocidad (ascenso y descenso) y el área de masticación en el plano horizontal.


Chewing has been studied from different points of view, using natural and artificial foods test. When analyzing cereal-based foods, from breakfast cereals to granola bars, the evidence is scarce. Investigate this type of food is important to understand the behavior of chewing, with foods of different compositions and textures, and how these characteristics can influence the chewing process. Chewing was analyzed from a cinematic point of view, in young subjects complete dental. The test food used was prototype granola and peanuts, last one has been studied in subjects with prosthetic rehabilitation and its consumption is recommended in this population. The kinematic characteristics of chewing were analyzed: number of cycles, chewing frequency, ascent and descent chewing speed, and the chewing area in the three planes of space. The masticatory movements were related to the bordering mandibular movements, that formed the Posselt polygon, which was also analyzed in the three spatial planes. In all the variables analyzed, granola showed higher values, except in the number of chewing cycles, only statistically significant differences (p = 0.03) were found when comparing speed (ascent and descent) and the chewing area in the horizontal plane.


Subject(s)
Humans , Male , Female , Adult , Young Adult , Biomechanical Phenomena , Mandible/physiology , Mastication/physiology , Arachis , Edible Grain , Electromagnetic Phenomena
5.
Int. j. odontostomatol. (Print) ; 13(4): 466-474, dic. 2019. tab, graf
Article in Spanish | LILACS | ID: biblio-1056486

ABSTRACT

RESUMEN: Tanto la limitación del movimiento mandibular como el auto reporte de síntomas de trastornos témporomandibulares (TTM) son utilizados como elementos para el diagnóstico de pacientes en la clínica. Sin embargo, la relación entre la presencia de síntomas y el movimiento mandibular no está del todo clara. Por ello, el objetivo de este estudio fue relacionar la presencia de síntomas asociados a TTM con el movimiento mandibular en una muestra de sujetos adultos jóvenes y sanos. En este estudio exploratorio participaron 40 estudiantes de Odontología, médicamente sanos, con arco dentario maxilar y mandibular continuo y completo (hasta el primer molar). A cada uno se les solicitó responder un cuestionario de auto-reporte de síntomas asociados a TTM recomendado por la American Academy of Orofacial Pain (AAOP). También se realizó un registro y análisis de sus movimientos mandibulares utilizando articulografía electromagnética 3D, con el objetivo de correlacionar la presencia de síntomas con el rango y trayectoria de apertura, y el área comprendida en lo que se describe como polígono de Posselt en el plano frontal y sagital. No se encontraron diferencias significativas entre las respuestas a cada pregunta entre hombres y mujeres. De acuerdo a las respuestas y según Delcanho (1994), 12 participantes resultaron necesitar una evaluación más exhaustiva. En este grupo se encontró que el área del polígono de Posselt en el plano frontal, fue significativamente menor que el de aquellos participantes que no requieren una evaluación más exhaustiva (p=0,003). Los valores de la trayectoria de apertura mandibular varían según de que síntoma se trate. Los principales síntomas que afectarían los valores de los movimientos bordeantes son la "dificultad para abrir la boca" y el "ruido en las articulaciones mandibulares". Con este estudio, hemos puesto de manifiesto que la limitación del movimiento mandibular como signo de TTM debe evaluarse con cautela, debido a que según la presencia de determinados síntomas y otras características de los sujetos (como el sexo), su valor podría variar.


ABSTRACT: Both the limitation of mandibular movement and the self-report of symptoms of temporomandibular disorders (TMD) are used for the diagnosis of patients in clinical diagnosis. However, the relationship between the symptoms and mandibular movement is not entirely clear. Therefore, the objective of this study was to relate the presence of symptoms associated with TMD with mandibular movement in a sample of young and healthy adult subjects. This exploratory study involved 40 medically healthy dentistry students with a continuous and complete maxillary and mandibular arch (up to the first molar). Each subject was asked to answer a self-report questionnaire for symptoms associated with TTM recommended by the American Academy of Orofacial Pain (AAOP). We also recorded and analyzed their mandibular movements using 3D electromagnetic articulography, with the aim of correlating the presence of symptoms with the range and trajectory of opening, and the area included in what is described as a polygon of Posselt in the frontal and sagittal plane. No significant differences were found between the answers to each question between men and women. According to the responses and to Delcanho, 12 participants turned out to need a more exhaustive evaluation. In this group it was found that the area of the Posselt polygon in the frontal plane was significantly smaller than that of those participants who did not require a more extensive evaluation (p = 0.003). The values of the mandibular opening path vary depending on the symptom involved. The main symptoms that would affect the values of the bordering movements are the "difficulty to open the mouth" and "noise in the mandibular joints". With this study, we have shown that the limitation of mandibular movement as a sign of TMD should be assessed with caution, as, according to the presence of certain symptoms and other characteristics of subjects (such as sex), its value may vary.


Subject(s)
Humans , Male , Female , Young Adult , Temporomandibular Joint/pathology , Temporomandibular Joint Disorders/diagnosis , Electromagnetic Phenomena , Chile , Surveys and Questionnaires , Mandible , Masticatory Muscles/physiology , Mouth/anatomy & histology , Mouth/physiology , Movement
6.
Medisan ; 22(4)abr. 2018. ilus
Article in Spanish | LILACS | ID: biblio-894715

ABSTRACT

Se efectuó una revisión bibliográfica para determinar el impacto de la mecatrónica en el sector de la salud. Se valoró el desarrollo de esta desde la visión de diferentes investigadores, lo cual ha permitido su inserción en dicho sector. También se comprobó que la robótica y el procesamiento digital de imágenes y señales tienen mayor incidencia en la medicina. Asimismo, se hizo un análisis de la mecatrónica aplicada a esta ciencia, el cual demostró que las áreas quirúrgica y terapéutica son las más favorecidas y se nutren de técnicas innovadoras, que resultan más fiables y menos invasivas para el paciente


A literature review was carried out to determine the impact of mechatronic in the health sector. Its development was evaluated from the point of view of different investigators, which has allowed its insertion in this sector. It was also proven that robotics and digital processing of images and signs have higher incidence in medicine. Also, an analysis of mechatronic applied to this science was carried out, which demonstrated that the surgical and therapeutical areas are the most favored and receive nourishment through innovative techniques that are more reliable and less invasive for the patient


Subject(s)
Humans , Male , Female , Robotics/methods , Electronics, Medical/instrumentation , Electrical Equipment and Supplies , Robotic Surgical Procedures , Health Systems , Electromagnetic Phenomena , Wearable Electronic Devices/statistics & numerical data
7.
Article in Chinese | WPRIM | ID: wpr-774504

ABSTRACT

This paper realized an electromagnetic tracking system based on electrically-controlled rotating magnetic field. A tracking system using the digital signal processor (DSP) as the control processing device was developed, including a controllable constant current source module, a magnetic field source module, a three-axis magnetic sensor and ADC interface circuit. The experimental results verified that each time the system could be stable positioning, average error of position was 0.282 cm, the average error of orientation was 0.696o, the positioning time was 1.572 s. Through calibration and further improvement of the hardware circuit, the performance of the system is expected to further improve.


Subject(s)
Calibration , Electromagnetic Phenomena , Equipment Design , Magnetic Fields
8.
Article in Chinese | WPRIM | ID: wpr-774490

ABSTRACT

ISO 14708-3 "Implants for surgery-active implantable medical devices-Part 3:implantable neurostimulators" 2017 version and 2008 version are compared, and changes in the standard are interpreted combined with the characteristics of the neurostimulator. The new version of the standard for the first time in the introduction mentioned a new type of non-electrode or extension's neurostimulator. Key issues that have significant impact on safety concerns such as wireless charging temperature rise, MRI acceptance criteria, etc., are given for the first time in the new version. New requirements to the wireless communication section are added, and the electromagnetic compatibility part is greatly adjusted. With more miniature non-electrode or extension's neurostimulator entering the market, standards such as electromagnetic compatibility and MRI, there will be greater adjustments.


Subject(s)
Electromagnetic Phenomena , Implantable Neurostimulators , Reference Standards , Magnetic Resonance Imaging , Prostheses and Implants , Reference Standards
9.
Article in Chinese | WPRIM | ID: wpr-689819

ABSTRACT

Magnetic anchor technique can reduce the number of trocar in laparoscopic surgery. The laparoscopic magnetic anchor system consists of an external anchor magnet and the magnetic clutch system. Electromagnetic control laparoscopic surgery clutch system includes the internal grasper and the operating forceps. In this design, a permanent magnet is set at the tail of the internal grasper, and an electromagnetic device is installed at the head of the operating forceps. The magnetic field direction of the electromagnetic device can be changed by switching the positive pole and the negative pole of the electromagnetic device, so as to control the separation and combination of the operating forceps and the internal grasper. The design of this system is ingenious, easy to manufacture and the operation is simple.


Subject(s)
Electromagnetic Phenomena , Equipment Design , Laparoscopy , Magnetics , Surgical Instruments
10.
Article in Chinese | WPRIM | ID: wpr-689814

ABSTRACT

This paper introduces ISO 14708-3:2017, the new edition of the international standard for implantable neurostimulator, and emphasizes the new requirements in the clause of protection from RF electromagnetic interference. To meet this new requirements, this paper presents a design of torso simulator for the testing of implantable neurostimulator. The design includes volume conductor, electrodes and grids, which can simulate the actual operating environment of implantable neurostimulator in RF electromagnetic interference testing. The torso simulator is verified by performance in the last part of the paper.


Subject(s)
Electromagnetic Fields , Electromagnetic Phenomena , Implantable Neurostimulators , Reference Standards , Torso
11.
Rev. Méd. Clín. Condes ; 26(3): 387-392, mayo 2015. ilus, tab
Article in Spanish | LILACS | ID: biblio-1129140

ABSTRACT

La Broncoscopia es sin duda el ámbito de medicina respiratoria que más ha sufrido cambios en los últimos 30 años. Principalmente dado por los avances tecnológicos que han permitido llegar, ver y hacer mucho más de lo que se pensó que era factible por vía endoscópica.


The most evolved area in the respiratory medicine in the last 30 years, is without any doubt the Bronchoscopy. This are the results of the tecnological advances, that let us go, see and do, further than we thougth by endoscopy.


Subject(s)
Humans , Respiratory Tract Diseases/surgery , Respiratory Tract Diseases/diagnosis , Bronchoscopy/methods , Bronchoscopy/trends , Video Recording , User-Computer Interface , Bronchoscopy/instrumentation , Ultrasonography , Microscopy, Confocal , Tomography, Optical Coherence , Electromagnetic Phenomena , Fluorescence
12.
Article in Chinese | WPRIM | ID: wpr-310304

ABSTRACT

With the enforcement of YY 0505-2012, the testing items and evaluation points of radio frequency ablation catheter in electromagnetic compatibility field should be studied and discussed. Based on the requirements of relevant standards, this paper discusses on the testing items that should be applied and the evaluation points that should be focused on by analyzing the intended use and the structure of radio frequency ablation catheter, when it intends to apply registration individually with the basic knowledge of electromagnetic compatibility field.


Subject(s)
Catheter Ablation , Electromagnetic Fields , Electromagnetic Phenomena , Evaluation Studies as Topic
13.
Article in Chinese | WPRIM | ID: wpr-259921

ABSTRACT

A new system of blood flow block for control of bleeding in abdominal operation is composed of an abdominal magnetic blocking unit, an abdominal external electromagnet unit and other non-magnetic operation instrument. The abdominal external electromagnetic unit is placed in advance in the operation bed. The abdominal magnetic blocking unit can be placed directly on the ventral of the large vessels when need to blocking the abdominal large vessels during the operation. According to the non-contact suction characteristics of magnetic materials, the two magnetic units will attract each other and compression the vessels. Using this system for vascular occlusion does not need clear exposure and without separating vessel. There is the advantage of rapid, accurate and reliable for the system.


Subject(s)
Abdomen , Blood Loss, Surgical , Electromagnetic Phenomena , Equipment Design , Surgical Equipment
14.
Journal of Biomedical Engineering ; (6): 1384-1388, 2014.
Article in Chinese | WPRIM | ID: wpr-266745

ABSTRACT

Along with the development of computer technologies and digitization of human body's information, the digital human entered into a new stage of modelling physical features from the stage of reconstructing anatomical structures. By summarizing domestic and abroad relevant documents, we in this paper present the general scheme of digital human and the location of physical human as well as its conception and applied value. We especially analyze the modeling process of physical human, core technologies and its research and applications in four main fields: electromagnetic radiation, ultrasound propagation, bioimpedance measurements and biomechanical analysis. We also analyze and summarize existing problems of present physical human model and point out the future development trends of physical human.


Subject(s)
Biomechanical Phenomena , Electric Impedance , Electromagnetic Phenomena , Humans , Models, Anatomic , Software , Ultrasonics
15.
Indian J Biochem Biophys ; 2013 Aug; 50(4): 259-265
Article in English | IMSEAR | ID: sea-148605

ABSTRACT

Electromagnetic fields (EMFs) can increase free radicals, activate the stress response and alter enzyme reactions. Intracellular signalling is mediated by free radicals and enzyme kinetics is affected by radical pair recombination rates. The magnetic field component of an external EMF can delay the "recombination rate" of free radical pairs. Magnetic fields thus increase radical life-times in biological systems. Although measured in nanoseconds, this extra time increases the potential to do more damage. Melatonin regulates the body's sleep-wake cycle or circadian rhythm. The World Health Organization (WHO) has confirmed that prolonged alterations in sleep patterns suppress the body's ability to make melatonin. Considerable cancer rates have been attributed to the reduction of melatonin production as a result of jet lag and night shift work. In this study, changes in circadian rhythm and melatonin concentration are observed due to the external perturbation of chemical reaction rates. We further analyze the pineal melatonin rhythm and investigate the critical time delay or maturation time of radical pair recombination rates, exploring the impact of the mRNA degradation rate on the critical time delay. The results show that significant melatonin interruption and changes to the circadian rhythm occur due to the perturbation of chemical reaction rates, as also reported in previous studies. The results also show the influence of the mRNA degradation rate on the circadian rhythm’s critical time delay or maturation time. The results support the hypothesis that exposure to weak EMFs via melatonin disruption can adversely affect human health.


Subject(s)
Circadian Rhythm , Electromagnetic Phenomena , Environmental Exposure/adverse effects , Humans , Melatonin/metabolism , Models, Biological , Pineal Gland/metabolism , Pineal Gland/physiology , Time Factors
16.
Article in Chinese | WPRIM | ID: wpr-264255

ABSTRACT

Through a range of clinical applications of the new generation Aurora electromagnetic tracking system, it's performance and the significance in the medical surgical navigation are introduced. Its advantages and the development direction for clinical work are described that it can provide a newer, broader application space, enhance the accuracy and controllability of surgical navigation.


Subject(s)
Electromagnetic Phenomena , Surgery, Computer-Assisted , Methods
17.
Rev. bras. odontol ; 69(2): 260-265, Jul.-Dez. 2012. ilus, tab
Article in Portuguese | LILACS | ID: lil-720355

ABSTRACT

Localizadores Apicais Eletrônicos (LAE) podem interferir com Marcapasso Cardíaco (MP) por gerarem interferência eletromagnética (IEM). O objetivo do artigo foi avaliar, in vitro, a IEM causada por LAE em um MP. Quatro LAE (Apex DSP, NovApex N-21, RomiApex A-15, C-ROOT I) tiveram seus eletrodos imersos em uma solução salina a distâncias de 10, 15, 20, 25 e 30 cm do eletrodo de um MP (Medtronic Sensia SEDR01) monitorado por telemetria. Com 0,2mV de sensibilidade, o MP sofreu interferência dos 4 LAE, apresentando inibição, reinício do ciclo ou deflagração. Com 2mV de sensibilidade, não houve interferências. Independente da sensibilidade do MP, nenhum LAE provocou reversão para assíncrono ou desprogramação. Quando em máxima sensibilidade, o MP sofreu interferências, porém esta não é uma situação observada in vivo.


Electronic Apex Locators (EAL) may interfere with Cardiac Pacemakers (PM) by electromangnetic interference (EMI). The purpose of this article was to evaluate, in vitro, the EMI caused by EAL on a PM. Four different EAL (Apex DSP, NovApex N-21, RomiApex A-15, C-ROOT I) had their electrodes immersed in a saline solution at distances of 10, 15, 20, 25 and 30 cm from the electrode of the PM (Medtronic Sensia SEDR01) monitored by telemetry. With 0.2 mV sensitivity, the PM had interference from all 4 EAL, with inhibition, stimulation recycle, and deflagration. With 2mV sensitivity, no interference was observed. Regardless the PM sensitivity, no EAL was able to lead, even at short distances, reversion to asynchronous or deprogramming. When set to maximum sensitivity, the PM suffered interference, although that wouldn't be a real in vivo situation.


Subject(s)
Pacemaker, Artificial , Root Canal Preparation/instrumentation , Endodontics , Electromagnetic Phenomena
18.
Article in English | WPRIM | ID: wpr-235596

ABSTRACT

<p><b>OBJECTIVE</b>We examined alterations in the expression of tumorigenesis-related genes in the pituitary gland of rats exposed to electromagnetic pulses (EMP).</p><p><b>METHODS</b>The global gene expression profiles of the pituitary gland in EMP-exposed and control groups were detected by cDNA microarray analysis. We then validated and further investigated the reduced expression of two tumorigenesis-related genes, Pten, and Jund, by assessing their mRNA and protein expression by quantitative real-time-PCR, western blotting, and immunohistochemistry in the pituitary gland of rats 6 months after exposure to EMP.</p><p><b>RESULTS</b>EMP exposure induced genome-wide gene expression changes in the rat pituitary gland. There was decreased expression of the Pten and Jund mRNAs and proteins in EMP-exposed rats compared with in unexposed control animals.</p><p><b>CONCLUSION</b>EMP exposure alters the expression of tumorigenesis-related genes in the pituitary gland. These tumorigenesis-related genes are potentially involved in the development of pituitary gland tumors in rats.</p>


Subject(s)
Adenoma , Genetics , Metabolism , Pathology , Animals , Down-Regulation , Electromagnetic Phenomena , Female , Gene Expression Profiling , Oligonucleotide Array Sequence Analysis , PTEN Phosphohydrolase , Genetics , Metabolism , Pituitary Gland , Metabolism , Pituitary Neoplasms , Genetics , Metabolism , Pathology , Proto-Oncogene Proteins c-jun , Genetics , Metabolism , Rats , Rats, Wistar , Real-Time Polymerase Chain Reaction
19.
Journal of Biomedical Engineering ; (6): 1128-1132, 2010.
Article in Chinese | WPRIM | ID: wpr-260925

ABSTRACT

In the light of optical theory, we advanc an ultra-wideband impulse radiating antenna (IRA) which is composed of an ellipsoidal reflector and a cone radiator. The high-intensity ultra-short electric pulses radiated by IRA can be transferred into the deep target in tissue non-invasively and be focused effectively. With the focused picosecond electric pulses, the organelles (mitochondria) transmembrane potential shall change to collapse under which the tumor cells will be targetly induced to apoptosis, so the method of non-invasive treatment of tumors would be achieved. Based on the time-domain electromagnetic field theory, the propagation characteristics of picosecond electric pulses were analyzed with and without the context of biological tissue, respectively. The results show that the impulse characteristics of input pulse were maintained and the picosecond electric pulses can keep high resolution in target areas. Meanwhile, because of the dispersive nature of medium, the pulse amplitude of the pulses will attenuate and the pulse width will be broadened.


Subject(s)
Apoptosis , Radiation Effects , Electric Stimulation Therapy , Methods , Electrodes , Electromagnetic Phenomena , Electroporation , Methods , Humans , Neoplasms , Pathology , Therapeutics
20.
Article in Chinese | WPRIM | ID: wpr-230745

ABSTRACT

In clinical application of microwave hyperthermia, multi-applicators are often simultaneously required to irradiate the tumor because of its large volume or its deep location. Power divider separates the input microwave energy into equal, or unequal, energy to each applicator. In this paper, the design procedure for the three-section transmission-line transformer based one-to-two equal-split Wilkinson power divider is introduced. By impedance analysis on equivalent scheme, the design parameter of power divider is provided, and by simulation and optimization on Ansoft HFSS, a microstrip structure Wilkinson power divider operating frequency 2. 45 GHz is given. Measurement test results from network analyzer show that it has 25% bandwidth and good isolation in output with this structure. Besides, it is characterized by small size and easy processing. This power divider suits microwave hyperthermia.


Subject(s)
Electric Impedance , Electromagnetic Phenomena , Equipment Design , Humans , Hyperthermia, Induced , Microwaves , Neoplasms , Therapeutics
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