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1.
Article in English | WPRIM | ID: wpr-1009925

ABSTRACT

Fear, a negative emotion triggered by dangerous stimuli, can lead to psychiatric disorders such as phobias, anxiety disorders, and depression. Investigating the neural circuitry underlying congenital fear can offer insights into the pathophysiological mechanisms of related psychiatric conditions. Research on innate fear primarily centers on the response mechanisms to various sensory signals, including olfactory, visual and auditory stimuli. Different types of fear signal inputs are regulated by distinct neural circuits. The neural circuits of the main and accessory olfactory systems receive and process olfactory stimuli, mediating defensive responses like freezing. Escape behaviors elicited by visual stimuli are primarily regulated through the superior colliculus and hypothalamic projection circuits. Auditory stimuli-induced responses, including escape, are mainly mediated through auditory cortex projection circuits. In this article, we review the research progress on neural circuits of innate fear defensive behaviors in animals. We further discuss the different sensory systems, especially the projection circuits of olfactory, visual and auditory systems, to provide references for the mechanistic study of related mental disorders.


Subject(s)
Animals , Humans , Fear/physiology , Nerve Net
2.
Int. j. morphol ; 40(2): 407-413, 2022. ilus
Article in English | LILACS | ID: biblio-1385603

ABSTRACT

SUMMARY: This study aims to extract teeth and alveolar bone structures in CBCT images automatically, which is a key step in CBCT image analysis in the field of stomatology. In this study, semantic segmentation was used for automatic segmentation. Five marked classes of CBCT images were input for U-net neural network training. Tooth hard tissue (including enamel, dentin, and cementum), dental pulp cavity, cortical bone, cancellous bone, and other tissues were marked manually in each class. The output data were from different regions of interest. The network configuration and training parameters were optimized and adjusted according to the prediction effect. This method can be used to segment teeth and peripheral bone structures using CBCT. The time of the automatic segmentation process for each CBCT was less than 13 min. The Dice of the evaluation reference image was 98 %. The U-net model combined with the watershed method can effectively segment the teeth, pulp cavity, and cortical bone in CBCT images. It can provide morphological information for clinical treatment.


RESUMEN: El objetivo del presente estudio fue extraer estructuras dentarias y óseas alveolares desde imágenes CBCT automáticamente, lo cual es un paso clave en el análisis de imágenes CBCT en el campo de la estomatología. En este estudio, se utilizó la segmentación de tipo emántica para la segmentación automática. Se ingresaron cinco clases de imágenes CBCT marcadas, para el entrenamiento de la red neuronal U-net. El tejido duro del diente (incluidos esmalte, dentina y cemento), la cavidad de la pulpa dentaria, hueso cortical, hueso esponjoso y otros tejidos se marcaron manualmente en cada clase. Los datos se obtuvieron de diferentes regiones de interés. La configuración de la red y los parámetros de entrenamiento se optimizaron y ajustaron de acuerdo con un análisis predictivo. Este método se puede utilizar para segmentar dientes y estructuras óseas periféricas mediante CBCT. El tiempo del proceso de segmentación automática para cada CBCT fue menor a 13 min. El "Dice" de evaluación de la imagen de referencia fue de 98 %. El modelo U-net combinado con el método "watershed"puede segmentar eficazmente los dientes, la cavidad pulpar y el hueso cortical en imágenes CBCT. Puede proporcionar información morfológica para el tratamiento clínico.


Subject(s)
Humans , Tooth/diagnostic imaging , Dental Pulp/diagnostic imaging , Cone-Beam Computed Tomography , Tooth/anatomy & histology , Artificial Intelligence , Dental Pulp/anatomy & histology , Nerve Net
3.
J. biomed. eng ; Sheng wu yi xue gong cheng xue za zhi;(6): 237-247, 2022.
Article in Chinese | WPRIM | ID: wpr-928219

ABSTRACT

Brain functional network changes over time along with the process of brain development, disease, and aging. However, most of the available measurements for evaluation of the difference (or similarity) between the individual brain functional networks are for charactering static networks, which do not work with the dynamic characteristics of the brain networks that typically involve a long-span and large-scale evolution over the time. The current study proposes an index for measuring the similarity of dynamic brain networks, named as dynamic network similarity (DNS). It measures the similarity by combining the "evolutional" and "structural" properties of the dynamic network. Four sets of simulated dynamic networks with different evolutional and structural properties (varying amplitude of changes, trend of changes, distribution of connectivity strength, range of connectivity strength) were generated to validate the performance of DNS. In addition, real world imaging datasets, acquired from 13 stroke patients who were treated by transcranial direct current stimulation (tDCS), were used to further validate the proposed method and compared with the traditional similarity measurements that were developed for static network similarity. The results showed that DNS was significantly correlated with the varying amplitude of changes, trend of changes, distribution of connectivity strength and range of connectivity strength of the dynamic networks. DNS was able to appropriately measure the significant similarity of the dynamics of network changes over the time for the patients before and after the tDCS treatments. However, the traditional methods failed, which showed significantly differences between the data before and after the tDCS treatments. The experiment results demonstrate that DNS may robustly measure the similarity of evolutional and structural properties of dynamic networks. The new method appears to be superior to the traditional methods in that the new one is capable of assessing the temporal similarity of dynamic functional imaging data.


Subject(s)
Humans , Aging/physiology , Brain/physiology , Brain Mapping , Magnetic Resonance Imaging/methods , Nerve Net/physiology , Transcranial Direct Current Stimulation/methods
4.
Rev. colomb. ortop. traumatol ; 36(1): 2-8, 2022. ilus.
Article in Spanish | LILACS, COLNAL | ID: biblio-1378755

ABSTRACT

Objetivo Confirmar factibilidad técnica de la neurotización del nervio axilar por la rama motora de la porción larga del tríceps con el fin de definir la anatomía quirúrgica de los nervios radial y axilar. Materiales y métodos Veinte hombros de cadáver fueron intervenidos para transferencia de la rama del Nervio Radial para la porción larga del tríceps a la rama anterior del Nervio Axilar por abordaje axilar. Se confirmó la escogencia correcta del nervio receptor por abordaje posterior. Resultados Se logró una disección adecuada de la primera rama motora del nervio radial del nervio axilar y de la rama anterior del Nervio Axilar. El origen de la rama motora se encontró en promedio a 3,8mm (+/- 7,3mm) distal al borde superior del tendón del dorsal ancho. El nervio axilar se encontró cefálico al borde superior del dorsal ancho a una distancia promedio de 11,3mm (+/-2,13mm) y distal al redondo menor 3.05mm (+/- 1,3mm), sutura con la primera rama del radial en el 100% de los casos sin tensión y se confirmó la adecuada transferencia en todos los casos. Conclusión La neurotización del nervio axilar con la primera rama del nervio radial se logró con éxito en el 100% por vía axilar. Este abordaje es adecuado, evitando tener que realizar cambios de posición a prono y doble abordaje, y si se requiere procedimientos adicionales de reconstrucción en el mismo tiempo quirúrgico tipo Oberlin y exploraciones supraclaviculares del plexo braquial se pueden realizar sin cambio de posición.


Objective To confirm the technical feasibility of neurotization of the axillary nerve by the motor branch of the long head of the triceps in order to define the surgical anatomy of the radial and axillary nerves. Materials and method Twenty cadaver shoulders were operated on for transfer of the radial nerve branch for the long head of the triceps to the anterior branch of the axillary nerve by axillary approach. The correct choice of the receiving nerve was confirmed by posterior approach. Results An adequate dissection of the first motor branch of the radial nerve of the axillary nerve and of the anterior branch of the Axillary Nerve was achieved, The origin of the motor branch was found on average at 3.8mm (+/−7.3mm) distal to the superior border of the latissimus dorsi tendon. The axillary nerve was found 11.3mm (+/−2.13mm) cephalad to the upper border of the latissimus dorsi and 3.05mm (+/−1.3mm) distal to the teres minor. A tensionless coaptation was obtained in all cases. Conclusion Neurotization of the axillary nerve with the first branch of the radial nerve was successfully achieved through the axillary approach. This approach is adequate, avoiding position change to prone and double approach, and if additional reconstruction procedures are required at the same surgical time, Oberlin type and supraclavicular explorations of the brachial plexus can be performed without changing position.


Subject(s)
Humans , Nerve Transfer , Radial Nerve , Brachial Plexus , Nerve Net
6.
Rev. chil. cir ; 71(1): 15-21, feb. 2019. tab, ilus
Article in Spanish | LILACS | ID: biblio-985373

ABSTRACT

Resumen Introducción: Conocer en detalle la inervación interna del músculo temporal humano permite realizar múltiples técnicas quirúrgicas y tratamientos de patologías que involucran al territorio craneofacial. Si bien en la literatura se ha descrito la inervación interna del músculo temporal humano basado en micro-disección directa, la técnica de tinción de Sihler es una herramienta ventajosa para el estudio anatómico ya que permite observar ramos nerviosos pequeños sin perder su relación tridimensional con las fibras musculares. Objetivo: Describir la distribución nerviosa al interior del músculo temporal humano en cadáveres al aplicar el método de Sihler y analizar su asociación anátomo quirúrgica. Materiales y Método: Ocho músculos temporales humanos previamente disecados fueron sometidos al método de tinción de Sihler. Cada una de las muestras se observó bajo lupa estereoscópica y transiluminación; finalmente para su descripción se dividió al músculo en tres regiones. Resultados: Se determinó la presencia de tres troncos nerviosos principales: el temporal profundo anterior, el temporal profundo medio y temporal profundo posterior, los que discurren de profundo a superficial. Además, se observaron ramos colaterales de menor calibre del nervio temporal profundo posterior que en forma de arco comunican las tres regiones del músculo. Conclusión: Se describió una distribución nerviosa interna común para los músculos estudiados en las tres dimensiones del espacio, conocimiento útil para innovar en terapias clínico-quirúrgicas del territorio craneofacial.


Introduction: Knowing in detail the inner innervation of the human temporal muscle allows to perform multiple surgical techniques and treatments of pathologies that involve the craniofacial territory. Although the internal innervation of the human temporal muscle based on direct microdissection has been described in the literature, the Sihler staining technique is an advantageous tool for anatomical study since it allows observing small nerve branches without losing its three-dimensional relationship with muscle fibers. Aim: To describe the nervous distribution within the human temporal muscle in cadavers by applying the Sihler method and analyzing its surgical anatomical association. Materials and Method: Eight previously dissected human temporal muscles were subjected to the Sihler staining method. Each one of the samples was observed under stereoscopic magnification and transillumination, finally for its description the muscle was divided into three regions. Results: The presence of three main nervous trunks was determined: the anterior deep temporal, the deep medium temporal and the posterior deep temporal, those that run from deep to superficial. In addition, collateral branches of lesser caliber of the posterior deep temporal nerve that in the form of an arc communicate the three regions of the muscle were observed. Conclusion: A common internal nervous distribution was described for the muscles studied in the three dimensions of space, useful knowledge to innovate in clinical-surgical therapies of the craniofacial territory.


Subject(s)
Humans , Temporal Muscle/physiopathology , Temporal Muscle/diagnostic imaging , Nerve Net , Temporal Muscle/surgery , Craniofacial Abnormalities/pathology , Neural Pathways
7.
Neuroscience Bulletin ; (6): 113-123, 2019.
Article in English | WPRIM | ID: wpr-775444

ABSTRACT

The recent development of tools to decipher the intricacies of neural networks has improved our understanding of brain function. Optogenetics allows one to assess the direct outcome of activating a genetically-distinct population of neurons. Neurons are tagged with light-sensitive channels followed by photo-activation with an appropriate wavelength of light to functionally activate or silence them, resulting in quantifiable changes in the periphery. Capturing and manipulating activated neuron ensembles, is a recently-designed technique to permanently label activated neurons responsible for a physiological function and manipulate them. On the other hand, neurons can be transfected with genetically-encoded Ca indicators to capture the interplay between them that modulates autonomic end-points or somatic behavior. These techniques work with millisecond temporal precision. In addition, neurons can be manipulated chronically to simulate physiological aberrations by transfecting designer G-protein-coupled receptors exclusively activated by designer drugs. In this review, we elaborate on the fundamental concepts and applications of these techniques in research.


Subject(s)
Animals , Humans , Autonomic Pathways , Physiology , Calcium Signaling , Physiology , Nerve Net , Physiology , Neurons , Physiology , Optogenetics , Methods , Receptors, G-Protein-Coupled , Physiology
8.
Neuroscience Bulletin ; (6): 133-144, 2019.
Article in English | WPRIM | ID: wpr-775466

ABSTRACT

Autonomic disturbances often occur in patients with acute cerebrovascular disease due to damage of the central autonomic network. We summarize the structures of the central autonomic network and the clinical tests used to evaluate the functions of the autonomic nervous system. We review the clinical and experimental findings as well as management strategies of post-stroke autonomic disturbances including electrocardiographic changes, cardiac arrhythmias, myocardial damage, thermoregulatory dysfunction, gastrointestinal dysfunction, urinary incontinence, sexual disorders, and hyperglycemia. The occurrence of autonomic disturbances has been associated with poor outcomes in stroke patients. Autonomic nervous system modulation appears to be an emerging therapeutic strategy for stroke management in addition to treatments for sensorimotor dysfunction.


Subject(s)
Animals , Humans , Acute Disease , Autonomic Nervous System , Cerebrovascular Disorders , Nerve Net , Wounds and Injuries , Sensorimotor Cortex , Stroke
9.
West Indian med. j ; West Indian med. j;67(3): 243-247, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-1045851

ABSTRACT

ABSTRACT This paper presents an improved classification system for brain tumours using wavelet transform and neural network. The anisotropic diffusion filter was used for image denoising, and the performance of the oriented rician noise reducing anisotropic diffusion (ORNRAD) filter was validated. The segmentation of the denoised image was carried out by fuzzy c-means clustering. The features were extracted using symlet and coiflet wavelet transforms, and the Levenberg-Marquardt algorithm based neural network was used to classify the magnetic resonance (MR) images. This classification technique of MR images was tested and analysed with existing methods, and its performance was found to be satisfactory with a classification accuracy of 93.24%. The developed system could assist physicians in classifying MR images for better decision-making.


RESUMEN Este artículo presenta un sistema de clasificación mejorado para los tumores de cerebro usando la transformada de ondeletas (transformada wavelet) y la red neuronal. El filtro de difusión anisotrópica fue utilizado para la eliminación del ruido de la imagen, y se validó el funcionamiento del filtro de difusión anisotrópica orientado a reducir el ruido riciano (ORNRAD, siglas en inglés). La segmentación de la imagen 'desruidizada ' (denoised) fue realizada mediante el agrupamiento difuso c-means fuzzy. Las características fueron extraídas usando las transformadas de ondeletas symlet y coiflet, y la red neuronal basada en el algoritmo de Levenberg-Marquardt fue utilizada para clasificar las imágenes de resonancia magnética (RM) imágenes. Esta técnica de clasificación de imágenes de RM fue probada y analizada con métodos existentes, y se halló que su rendimiento era satisfactorio con una precisión de clasificación de 93.24%. El sistema desarrollado podría ayudar a los médicos a clasificar imágenes de RM para una mejor toma de decisiones.


Subject(s)
Humans , Brain Neoplasms/classification , Brain Neoplasms/diagnostic imaging , Wavelet Analysis , Nerve Net/diagnostic imaging , Magnetic Resonance Imaging
10.
Rev. chil. nutr ; 45(3): 216-222, set. 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-959483

ABSTRACT

RESUMEN El objetivo del artículo fue lustrar mediante modelos de predicción microbiológica, la probabilidad de conformidad del producto terminado, estimando el ciclo de vida de la leche en polvo una vez que ha sido reconstituida, enfocado en los aspectos fisicoquímicos y microbiológicos (Bacillus cereus), por medio del modelo cinético de Arrhenius, con redes neuronales artificiales, entrenadas para pronosticar productos conformes respecto a la bacteria. A través del algoritmo de la red neuronal, se concluyó que, una vez la leche en polvo ha sido reconstituida debe mantenerse refrigerada entre 4°C y 6°C, para obtener una vida útil alrededor de los 19 días, pronosticando el 98% de productos conformes.


ABSTRACT The aim of this paper was to show a microbiological prediction model to determine the probability of conformity in products and estimate the life cycle of reconstituted powdered milk, focusing on the physicochemical and microbiological aspects of Bacillus cereus. We used the kinetic model Arrhenius, built under artificial neural networks designed to measure conformity to Bacillus cereus products. Using the neural network algorithm, we found that once milk powder was reconstituted, the temperature should be between 4°C and 6°C to obtain a lifespan around 19 days and 98% conformity.


Subject(s)
Food Quality , Dried Full-Cream Milk , Bacillus cereus , Food Microbiology , Nerve Net
11.
Pesqui. bras. odontopediatria clín. integr ; 18(1): 3978, 15/01/2018. ilus, tab, graf
Article in English | LILACS, BBO | ID: biblio-966743

ABSTRACT

Objective: To develop diagnostic reference for arch form using Artificial Neuron Network (ANN) from tooth size and arch dimension variables on scanned-dental cast from patients with class I malocclusion treated orthodontically. Material and Methods: One hundred and ninety pairs of dental cast pre-post orthodontic treatment gathered from Orthodontic clinics were scanned and then all dimension variables were measured using Image Tool (gender, tooth size and arch dimension). The multivariate data were analyzed statistically using Stata (Lakeway Drive, College Station, Texas USA). The statistic results were compiled to build the neuron network software for analyzing arch form. Results: Gender and all variables from pre-treatment do not influence arch form. Intercanine width, canine depth, intermolar width, and molar depth are variables that influence arch form. The result of the statistical analyses can be used to develop software based on artificial neural network. Output program is the arch form, such as oval, square or tapered. The software can describe arch form with the accuracy of 76.31%. Conclusion: A software using Artificial Neuron Network to describe arch form can be used for diagnostic reference to Class I malocclusion.


Subject(s)
Software , Dental Arch , Malocclusion , Nerve Net , Tooth Movement Techniques/methods , Multivariate Analysis , Indonesia
12.
Neuroscience Bulletin ; (6): 186-193, 2018.
Article in English | WPRIM | ID: wpr-777076

ABSTRACT

In 1905, Henry Head first suggested that transmission of pain-related protopathic information can be negatively modulated by inputs from afferents sensing innocuous touch and temperature. In 1965, Melzak and Wall proposed a more concrete gate control theory of pain that highlights the interaction between unmyelinated C fibers and myelinated A fibers in pain transmission. Here we review the current understanding of the spinal microcircuits transmitting and gating mechanical pain or itch. We also discuss how disruption of the gate control could cause pain or itch evoked by innocuous mechanical stimuli, a hallmark symptom for many chronic pain or itch patients.


Subject(s)
Animals , Humans , Nerve Net , Pathology , Pain , Pathology , Pruritus , Pathology , Spinal Cord , Pathology , Synaptic Transmission , Physiology
13.
Neuroscience Bulletin ; (6): 1007-1016, 2018.
Article in English | WPRIM | ID: wpr-775489

ABSTRACT

Exploring the transition from inter-ictal to ictal epileptiform discharges (IDs) and how GABA receptor-mediated action affects the onset of IDs will enrich our understanding of epileptogenesis and epilepsy treatment. We used Mg-free artificial cerebrospinal fluid (ACSF) to induce epileptiform discharges in juvenile mouse hippocampal slices and used a micro-electrode array to record the discharges. After the slices were exposed to Mg-free ACSF for 10 min-20 min, synchronous recurrent seizure-like events were recorded across the slices, and each event evolved from inter-ictal epileptiform discharges (IIDs) to pre-ictal epileptiform discharges (PIDs), and then to IDs. During the transition from IIDs to PIDs, the duration of discharges increased and the inter-discharge interval decreased. After adding 3 μmol/L of the GABA receptor agonist muscimol, PIDs and IDs disappeared, and IIDs remained. Further, the application of 10 μmol/L muscimol abolished all the epileptiform discharges. When the GABA receptor antagonist bicuculline was applied at 10 μmol/L, IIDs and PIDs disappeared, and IDs remained at decreased intervals. These results indicated that there are dynamic changes in the hippocampal network preceding the onset of IDs, and GABA receptor activity suppresses the transition from IIDs to IDs in juvenile mouse hippocampus.


Subject(s)
Animals , Male , Mice , Animals, Newborn , Bicuculline , Pharmacology , Disease Models, Animal , Epilepsy , Pathology , GABA-A Receptor Agonists , Pharmacology , GABA-A Receptor Antagonists , Therapeutic Uses , Hippocampus , Metabolism , In Vitro Techniques , Magnesium , Metabolism , Pharmacology , Membrane Potentials , Mice, Inbred C57BL , Muscimol , Pharmacology , Nerve Net , Receptors, GABA-A , Metabolism
14.
Article in English | WPRIM | ID: wpr-1010433

ABSTRACT

The purpose of this study was to explore the differences in interhemispheric functional connectivity in patients with Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) based on a triple network model consisting of the default mode network (DMN), salience network (SN), and executive control network (ECN). The technique of voxel-mirrored homotopic connectivity (VMHC) analysis was applied to explore the aberrant connectivity of all patients. The results showed that: (1) the statistically significant connections of interhemispheric brain regions included DMN-related brain regions (i.e. precuneus, calcarine, fusiform, cuneus, lingual gyrus, temporal inferior gyrus, and hippocampus), SN-related brain regions (i.e. frontoinsular cortex), and ECN-related brain regions (i.e. frontal middle gyrus and frontal inferior); (2) the precuneus and frontal middle gyrus in the AD group exhibited lower VMHC values than those in the aMCI and healthy control (HC) groups, but no significant difference was observed between the aMCI and HC groups; and (3) significant correlations were found between peak VMHC results from the precuneus and Mini Mental State Examination (MMSE) and Montreal Cognitive Scale (MOCA) scores and their factor scores in the AD, aMCI, and AD plus aMCI groups, and between the results from the frontal middle gyrus and MOCA factor scores in the aMCI group. These findings indicated that impaired interhemispheric functional connectivity was observed in AD and could be a sensitive neuroimaging biomarker for AD. More specifically, the DMN was inhibited, while the SN and ECN were excited. VMHC results were correlated with MMSE and MOCA scores, highlighting that VMHC could be a sensitive neuroimaging biomarker for AD and the progression from aMCI to AD.


Subject(s)
Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Alzheimer Disease/physiopathology , Brain/diagnostic imaging , Brain Mapping , Cognitive Dysfunction/physiopathology , Magnetic Resonance Imaging , Memory , Models, Neurological , Nerve Net
15.
Iatreia ; Iatreia;29 (4): 433-444, Oct. 2016. ilus
Article in Spanish | LILACS | ID: biblio-834638

ABSTRACT

El concepto de redes en estado de reposo se refiere a fluctuaciones coherentes de la actividad cerebral, presentes en forma de redes que aparecen cuando los sujetos no están ocupados en alguna actividad o proceso cognitivo superior. Estas redes han sido identificadas en estudios de resonancia magnética funcional y reflejan un alto nivel de conectividad del cerebro humano. El concepto ha crecido en notoriedad hasta tal punto que ahora es casi rutina entre los grupos que usan resonancia magnética en sus investigaciones. Se ha estudiado la actividad de las redes en estado de reposo en el envejecimiento, el deterioro cognitivo leve y diversas enfermedades neurológicas y psiquiátricas. Además, se ha demostrado su existencia en otros primates y en ratas. En esta revisión se presenta una visión general del concepto, así como de las herramientas para la adquisición y el análisis. Igualmente se discuten algunas investigaciones relevantes sobre el tema y su impacto en diversas entidades clínicas.


The concept of resting state networks refers to coherent fluctuations of brain activity, which appear when the subjects are not engaged in any task or superior cognitive process. Such networks have been identified in functional magnetic resonance studies and reflect a high connectivity level of the human brain. The concept has gained notoriety and has become routine among groups using functional magnetic resonance in their studies. The activity of the resting state networks has been studied in ageing, mild cognitive impairment and several neurological and psychiatric diseases. Additionally, its existence has been proved in non-human primates and rats. A general overview of the concept is presented here, as well as the acquisition and analysis tools. Moreover, some relevant evidence on this subject matter as well as its impact on several clinical entities are discussed.


O conceito de redes em estado de repouso se refere a flutuações coerentes da atividade cerebral, presentes em forma de redes que aparecem quando os sujeitos não estão ocupados em alguma atividade ou processo cognitivo superior. Estas redes têm sido identificadas em estudos de ressonância magnética funcional e refletem um alto nível de conectividade do cérebro humano. O conceito tem crescido em notoriedade até tal ponto que agora é quase rotina entre os grupos que usam ressonância magnética em suas investigações. A atividade das redes em estado de repouso tem sido estudada em envelhecimento, deterioro cognitivo leve e diversas doenças neurológicas e psiquiátricas. Adicionalmente se há demostrado sua existência em outros primatas e em ratos. Nesta revisão se oferece uma visão geral do conceito, assim como das ferramentas para a aquisição e a análise. Igualmente se discutem algumas investigações relevantes sobre o assunto e seu impacto em diversas entidades clínicas.


Subject(s)
Humans , Cerebrum , Nerve Net , Magnetic Resonance Spectroscopy
16.
Rev. Univ. Ind. Santander, Salud ; 48(3): 311-319, Agosto 8, 2016. ilus, tab
Article in Spanish | LILACS | ID: lil-797455

ABSTRACT

Introducción: El diagnóstico del estado eritrocitario en frotis de sangre periférica es un proceso realizado normalmente de forma manual a partir de observación microscópica, lo cual implica una considerable inversión de tiempo y recursos, además de posibles problemas de subjetividad y dificultad en la reproducibilidad del diagnóstico. Objetivo: Desarrollar una aplicación que permita la clasificación automática de glóbulos rojos en frotis de sangre periférica, de utilidad como herramienta de ayuda diagnóstica. Metodología: Se usaron técnicas de procesamiento de imágenes para segmentar los eritrocitos en las fotografías microscópicas y medir en ellos área, perímetro, solidez, circularidad, excentricidad, textura y dimensión box-counting. Se usó una red neuronal artificial para clasificar los eritrocitos según sus características en siete clases, incluyendo normalidad y seis alteraciones patológicas. La red se entrenó de acuerdo con la clasificación de 262 eritrocitos realizada por un hematólogo experto. Los desarrollos se hicieron en matlab®, una poderosa plataforma de computación científica. Resultados: La red escogida alcanza el 97.3% de aciertos en los datos de validación. Las equivocaciones en la red corresponden a células de dudosa clasificación aún para un experto, por presentar características correspondientes a varias clasificaciones patológicas. Conclusiones: La aplicación desarrollada clasifica de manera rápida y acertada los diferentes tipos de glóbulos rojos presentes en una muestra microscópica de frotis de sangre periférica, siendo de utilidad como herramienta de apoyo diagnóstico.


Introduction: The process of erythrocyte classification in peripheral blood smear is normally done manually from microscopic observation. This implies not only a considerable investment of time and resources but also brings potential problems of subjectivity and difficulty in the reproducibility of diagnosis. Objective: To develop an application that allows the automatic classification of red blood cells in peripheral blood smears, as a diagnostic aid tool. Methodology: Image processing techniques were used in order to segment erythrocytes in the microscopic photographs and to measure characteristics as area, perimeter, solidity, circularity, eccentricity, texture and boxcounting dimension. An artificial neural network was used to classify the red blood cells in the images in seven classes, including normal and six pathological changes, according to their characteristics. The network was trained according to the classification of 262 erythrocytes by an expert hematologist. The developments were made in matlab®, a powerful scientific computing platform. Results: The chosen network reaches 97.3% correct in the validation data. Mistakes in the network correspond to cells with various pathological classifications features, which make them difficult to classify even for an expert. Conclusions: The developed application classifies quickly and accurately the different types of red blood cells in a microscopic sample of peripheral blood smear, so it could be useful as a diagnostic support tool.


Subject(s)
Humans , Erythrocyte Count , Erythrocytes , Blood , Image Processing, Computer-Assisted , Nerve Net
17.
Pesqui. vet. bras ; Pesqui. vet. bras;36(7): 652-656, jul. 2016. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: lil-794775

ABSTRACT

The thymus is a lymphoid organ and usually evaluated for the degree of lymphocyte loss with subjective histological techniques. This study aimed to adapt and to apply of the digital analysis of the lymphoid depletion system (ADDL) in the thymus in order to obtain a more accurate analysis. Glucocorticoid was used to induce immunosuppression in 55 broilers at 21 days of age; other 15 broilers were the control group. After euthanasia of the broilers, postmortem examination was made. Both thymic chains were collected and six lobes were selected for histological examination of the degree of lymphocyte depletion (scores 1 to 5) and for submission to all stages of processing by the ADDL system. The artificial constructed neural networks (ANN) obtained 94.03% of correct classifications. In conclusion, it was possible to adopt objective criteria to evaluate thymic lymphoid depletion with the ADDL system.(AU)


O timo é um órgão linfóide, que é normalmente avaliado para o grau de perda de linfócitos a partir de técnicas histológicas subjetivas. Este trabalho teve como objetivo a adaptação e aplicação do sistema de análise digital de depleção linfóide (ADDL) para o timo, a fim de tornar sua análise mais acurada. Glicocorticóides foram utilizados a fim de induzir imunossupressão em 55 aves de 21 dias de idade. Outras 15 aves formaram o grupo controle. Posteriormente, para cada um dos aves, realizou-se a eutanásia e necropsia. Ambas as cadeias do timo foram coletadas e foram selecionadas seis lóbulos para processamento histológico, análise quanto ao grau de depleção linfocitária (escores de 1-5) e submissão a todas as fases do processamento pelo sistema ADDL. Observou-se que a rede neural artificial (RNA) construída obteve 94,03% de classificações corretas. Em conclusão, foi possível adotar critérios objetivos para avaliar a depleção linfóide tímica utilizando o sistema ADDL.(AU)


Subject(s)
Animals , Chickens/physiology , Immunity, Cellular/physiology , Lymphocyte Depletion/veterinary , Lymphocytes/physiology , Nerve Net/physiology , Thymus Gland/physiopathology , Glucocorticoids/analysis
18.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;49(6): e5115, 2016. tab, graf
Article in English | LILACS | ID: lil-781415

ABSTRACT

We used biotinylated dextran amine (BDA) to anterogradely label individual axons projecting from primary somatosensory cortex (S1) to four different cortical areas in rats. A major goal was to determine whether axon terminals in these target areas shared morphometric similarities based on the shape of individual terminal arbors and the density of two bouton types: en passant (Bp) and terminaux (Bt). Evidence from tridimensional reconstructions of isolated axon terminal fragments (n=111) did support a degree of morphological heterogeneity establishing two broad groups of axon terminals. Morphological parameters associated with the complexity of terminal arbors and the proportion of beaded Bp vs stalked Bt were found to differ significantly in these two groups following a discriminant function statistical analysis across axon fragments. Interestingly, both groups occurred in all four target areas, possibly consistent with a commonality of presynaptic processing of tactile information. These findings lay the ground for additional work aiming to investigate synaptic function at the single bouton level and see how this might be associated with emerging properties in postsynaptic targets.


Subject(s)
Animals , Male , Nerve Net/anatomy & histology , Presynaptic Terminals , Somatosensory Cortex/anatomy & histology , Anatomy, Cross-Sectional , Biotin/analogs & derivatives , Dextrans , Fluorescent Dyes , Nerve Net/physiology , Neural Pathways/anatomy & histology , Neural Pathways/physiology , Photomicrography , Presynaptic Terminals/physiology , Rats, Wistar , Reference Values , Somatosensory Cortex/physiology
19.
Chin. j. integr. med ; Chin. j. integr. med;(12): 293-301, 2016.
Article in English | WPRIM | ID: wpr-287181

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the modulatory effect of acupuncture treatment on the resting-state functional connectivity of brain regions in migraine without aura (MWoA) patients.</p><p><b>METHODS</b>Twelve MWoA patients were treated with standard acupuncture treatment for 4 weeks. All MWoA patients received resting-state functional magnetic resonance imaging (fMRI) scanning before and after acupuncture treatment. Another 12 normal subjects matched in age and gender were recruited to serve as healthy controls. The changes of restingstate functional connectivity in MWoA patients before and after the acupuncture treatment and those with the healthy controls were compared.</p><p><b>RESULTS</b>Before acupuncture treatment, the MWoA patients had significantly decreased functional connectivity in certain brain regions within the frontal and temporal lobe when compared with the healthy controls. After acupuncture treatment, brain regions showing decreased functional connectivity revealed significant reduction in MWoA patients compared with before acupuncture treatment.</p><p><b>CONCLUSIONS</b>Acupuncture treatment could increase the functional connectivity of brain regions in the intrinsic decreased brain networks in MWoA patients. The results provided further insights into the interpretation of neural mechanisms of acupuncture treatment for migraine.</p>


Subject(s)
Female , Humans , Male , Acupuncture Therapy , Brain , Case-Control Studies , Demography , Magnetic Resonance Imaging , Migraine without Aura , Nerve Net , Rest , Treatment Outcome
20.
Salud colect ; 11(3): 301-330, jul.-sep. 2015.
Article in Spanish | LILACS | ID: lil-761804

ABSTRACT

Partiendo de la propuesta de Giovanni Berlinguer, de que los procesos de salud/enfermedad constituyen algunos de los principales espías de las contradicciones de un sistema, se describen en primer lugar algunos casos ocurridos en contextos capitalistas centrales y periféricos, así como en Estados denominados "socialistas reales", que permiten observar dicho papel. En segundo lugar, observamos los procesos y sobre todo las interpretaciones que se han desarrollado en América Latina y especialmente en México respecto del papel atribuido a la medicina tradicional en la identidad y pertenencia de los pueblos originarios, y que subrayan la incompatibilidad de las cosmovisiones indígenas con la biomedicina, analizando algunos proyectos que se impulsaron en términos de salud intercultural, y que concluyeron en su mayoría en fracasos, tanto desde el punto de vista de la salud, como político. Se subraya el contenido y la perspectiva casi exclusivamente ideológicos de dichos proyectos, y su poca relación con la realidad de los pueblos originarios. Por último, se trata de ver si la trayectoria de estas concepciones y programas de salud expresan y explican el notable repliegue que sufren desde hace casi diez años la mayoría de los movimientos étnicos en América Latina.


Following Giovanni Berlinguer's proposal that health/disease processes are one of the primary spies into the contradictions of a system, this article describes cases that occurred in central and peripheral capitalist contexts as well as in the so-called "real socialist" States that allow such a role to be seen. Secondly, we observe the processes and above all the interpretations developed in Latin America and especially Mexico regarding the role attributed to traditional medicine in the identity and sense of belonging of indigenous peoples, which emphasize the incompatibility of indigenous worldviews with biomedicine. To do so we analyze projects that were carried out under the notion of intercultural health, which in large part resulted in failure both in health and political terms. The almost entirely ideological content and perspective of these projects is highlighted, as is the scant relationship they hold with the reality of indigenous people. Lastly, the impact and role that the advance of these conceptualizations and health programs might have had in the disengagement experienced over the last nearly ten years in the ethnic movements of Latin America is considered.


Subject(s)
Humans , Brain/physiology , Choice Behavior/physiology , Models, Neurological , Nerve Net/physiology , Neuronal Plasticity/physiology , Psychomotor Performance/physiology , Algorithms , Computer Simulation
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