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2.
Med Phys ; 49(1): 443-460, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34755359

RESUMEN

PURPOSE: Automatic muscle segmentation is critical for advancing our understanding of human physiology, biomechanics, and musculoskeletal pathologies, as it allows for timely exploration of large multi-dimensional image sets. Segmentation models are rarely developed/validated for the pediatric model. As such, autosegmentation is not available to explore how muscle architectural changes during development and how disease/pathology affects the developing musculoskeletal system. Thus, we aimed to develop and validate an end-to-end, fully automated, deep learning model for accurate segmentation of the rectus femoris and vastus lateral, medialis, and intermedialis using a pediatric database. METHODS: We developed a two-stage cascaded deep learning model in a coarse-to-fine manner. In the first stage, the U2 -Net roughly detects the muscle subcompartment region. Then, in the second stage, the shape-aware 3D semantic segmentation method SASSNet refines the cropped target regions to generate the more finer and accurate segmentation masks. We utilized multifeature image maps in both stages to stabilize performance and validated their use with an ablation study. The second-stage SASSNet was independently run and evaluated with three different cropped region resolutions: the original image resolution, and images downsampled 2× and 4× (high, mid, and low). The relationship between image resolution and segmentation accuracy was explored. In addition, the patella was included as a comparator to past work. We evaluated segmentation accuracy using leave-one-out testing on a database of 3D MR images (0.43 × 0.43 × 2 mm) from 40 pediatric participants (age 15.3 ± 1.9 years, 55.8 ± 11.8 kg, 164.2 ± 7.9 cm, 38F/2 M). RESULTS: The mid-resolution second stage produced the best results for the vastus medialis, rectus femoris, and patella (Dice similarity coefficient = 95.0%, 95.1%, 93.7%), whereas the low-resolution second stage produced the best results for the vastus lateralis and vastus intermedialis (DSC = 94.5% and 93.7%). In comparing the low- to mid-resolution cases, the vasti intermedialis, vastus medialis, rectus femoris, and patella produced significant differences (p = 0.0015, p = 0.0101, p < 0.0001, p = 0.0003) and the vasti lateralis did not (p = 0.2177). The high-resolution stage 2 had significantly lower accuracy (1.0 to 4.4 dice percentage points) compared to both the mid- and low-resolution routines (p value ranged from < 0.001 to 0.04). The one exception was the rectus femoris, where there was no difference between the low- and high-resolution cases. The ablation study demonstrated that the multifeature is more reliable than the single feature. CONCLUSIONS: Our successful implementation of this two-stage segmentation pipeline provides a critical tool for expanding pediatric muscle physiology and clinical research. With a relatively small and variable dataset, our fully automatic segmentation technique produces accuracies that matched or exceeded the current state of the art. The two-stage segmentation avoids memory issues and excessive run times by using a first stage focused on cropping out unnecessary data. The excellent Dice similarity coefficients improve upon previous template-based automatic and semiautomatic methodologies targeting the leg musculature. More importantly, with a naturally variable dataset (size, shape, etc.), the proposed model demonstrates slightly improved accuracies, compared to previous neural networks methods.


Asunto(s)
Aprendizaje Profundo , Músculo Cuádriceps , Adolescente , Niño , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Rótula , Músculo Cuádriceps/diagnóstico por imagen
3.
Mo Med ; 118(5): 435-441, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34658436

RESUMEN

In this pilot study, we examined the efficacy of Osteopathic Manipulative Treatment (OMT) for improving symptoms of stress, anxiety, and depression (SAD) to determine a correlation between overall improvement in health and quality of life for first responders. Participants received weekly OMT or sham OMT targeting autonomic imbalance. Indicators of SAD were examined pre- and post-study. Overall, this pilot study suggests improvement in both the social-psychological (mental) self-assessments, and alterations in SAD-associated biomarkers from OMT.


Asunto(s)
Socorristas , Osteopatía , Ansiedad/terapia , Depresión/terapia , Humanos , Proyectos Piloto , Calidad de Vida
4.
Magn Reson Med ; 83(1): 139-153, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31402520

RESUMEN

PURPOSE: Our clinical understanding of the relationship between 3D bone morphology and knee osteoarthritis, as well as our ability to investigate potential causative factors of osteoarthritis, has been hampered by the time-intensive nature of manually segmenting bone from MR images. Thus, we aim to develop and validate a fully automated deep learning framework for segmenting the patella and distal femur cortex, in both adults and actively growing adolescents. METHODS: Data from 93 subjects, obtained from on institutional review board-approved protocol, formed the study database. 3D sagittal gradient recalled echo and gradient recalled echo with fat saturation images and manual models of the outer cortex were available for 86 femurs and 90 patellae. A deep-learning-based 2D holistically nested network (HNN) architecture was developed to automatically segment the patella and distal femur using both single (sagittal, uniplanar) and 3 cardinal plane (triplanar) methodologies. Errors in the surface-to-surface distances and the Dice coefficient were the primary measures used to quantitatively evaluate segmentation accuracy using a 9-fold cross-validation. RESULTS: Average absolute errors for segmenting both the patella and femur were 0.33 mm. The Dice coefficients were 97% and 94% for the femur and patella. The uniplanar, relative to the triplanar, methodology produced slightly superior segmentation. Neither the presence of active growth plates nor pathology influenced segmentation accuracy. CONCLUSION: The proposed HNN with multi-feature architecture provides a fully automatic technique capable of delineating the often indistinct interfaces between the bone and other joint structures with an accuracy better than nearly all other techniques presented previously, even when active growth plates are present.


Asunto(s)
Diagnóstico por Computador , Fémur/lesiones , Imagen por Resonancia Magnética , Osteoartritis de la Rodilla/diagnóstico por imagen , Dimensión del Dolor/métodos , Rótula/lesiones , Adolescente , Desarrollo del Adolescente , Adulto , Algoritmos , Cartílago/diagnóstico por imagen , Aprendizaje Profundo , Femenino , Fémur/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional , Masculino , Redes Neurales de la Computación , Rótula/diagnóstico por imagen , Reconocimiento de Normas Patrones Automatizadas , Reproducibilidad de los Resultados , Adulto Joven
5.
J Med Imaging (Bellingham) ; 6(2): 024007, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31205977

RESUMEN

Accurate and automated prostate whole gland and central gland segmentations on MR images are essential for aiding any prostate cancer diagnosis system. Our work presents a 2-D orthogonal deep learning method to automatically segment the whole prostate and central gland from T2-weighted axial-only MR images. The proposed method can generate high-density 3-D surfaces from low-resolution ( z axis) MR images. In the past, most methods have focused on axial images alone, e.g., 2-D based segmentation of the prostate from each 2-D slice. Those methods suffer the problems of over-segmenting or under-segmenting the prostate at apex and base, which adds a major contribution for errors. The proposed method leverages the orthogonal context to effectively reduce the apex and base segmentation ambiguities. It also overcomes jittering or stair-step surface artifacts when constructing a 3-D surface from 2-D segmentation or direct 3-D segmentation approaches, such as 3-D U-Net. The experimental results demonstrate that the proposed method achieves 92.4 % ± 3 % Dice similarity coefficient (DSC) for prostate and DSC of 90.1 % ± 4.6 % for central gland without trimming any ending contours at apex and base. The experiments illustrate the feasibility and robustness of the 2-D-based holistically nested networks with short connections method for MR prostate and central gland segmentation. The proposed method achieves segmentation results on par with the current literature.

6.
F1000Res ; 8: 1430, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32760576

RESUMEN

Biomedical translational research can benefit from informatics system that support the confidentiality, integrity and accessibility of data.  Such systems require functional capabilities for researchers to securely submit data to designated biomedical repositories. Reusability of data is enhanced by the availability functional capabilities that ensure confidentiality, integrity and access of data. A biomedical research system was developed by combining common data element methodology with a service-oriented architecture to support multiple disease focused research programs. Seven service modules are integrated together to provide a collaborative and extensible web-based environment. The modules - Data Dictionary, Account Management, Query Tool, Protocol and Form Research Management System, Meta Study, Repository Manager and globally unique identifier (GUID) facilitate the management of research protocols, submitting and curating data (clinical, imaging, and derived genomics) within the associated data repositories. No personally identifiable information is stored within the repositories. Data is made findable by use of digital object identifiers that are associated with the research studies. Reuse of data is possible by searching through volumes of aggregated research data across multiple studies. The application of common data element(s) methodology for development of content-based repositories leads to increase in data interoperability that can further hypothesis-based biomedical research.


Asunto(s)
Investigación Biomédica , Biología Computacional , Lesiones Traumáticas del Encéfalo , Enfermedades Hereditarias del Ojo , Genómica , Humanos , Enfermedad de Parkinson , Enfermedades Raras
7.
F1000Res ; 7: 1353, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30356367

RESUMEN

Genomics and molecular imaging, along with clinical and translational research have transformed biomedical science into a data-intensive scientific endeavor. For researchers to benefit from Big Data sets, developing long-term biomedical digital data preservation strategy is very important. In this opinion article, we discuss specific actions that researchers and institutions can take to make research data a continued resource even after research projects have reached the end of their lifecycle. The actions involve utilizing an Open Archival Information System model comprised of six functional entities: Ingest, Access, Data Management, Archival Storage, Administration and Preservation Planning. We believe that involvement of data stewards early in the digital data life-cycle management process can significantly contribute towards long term preservation of biomedical data. Developing data collection strategies consistent with institutional policies, and encouraging the use of common data elements in clinical research, patient registries and other human subject research can be advantageous for data sharing and integration purposes. Specifically, data stewards at the onset of research program should engage with established repositories and curators to develop data sustainability plans for research data. Placing equal importance on the requirements for initial activities (e.g., collection, processing, storage) with subsequent activities (data analysis, sharing) can improve data quality, provide traceability and support reproducibility. Preparing and tracking data provenance, using common data elements and biomedical ontologies are important for standardizing the data description, making the interpretation and reuse of data easier. The Big Data biomedical community requires scalable platform that can support the diversity and complexity of data ingest modes (e.g. machine, software or human entry modes). Secure virtual workspaces to integrate and manipulate data, with shared software programs (e.g., bioinformatics tools), can facilitate the FAIR (Findable, Accessible, Interoperable and Reusable) use of data for near- and long-term research needs.


Asunto(s)
Investigación Biomédica , Ontologías Biológicas , Humanos , Difusión de la Información , Reproducibilidad de los Resultados , Programas Informáticos
9.
J Med Imaging (Bellingham) ; 4(4): 041302, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28840173

RESUMEN

Accurate automatic segmentation of the prostate in magnetic resonance images (MRI) is a challenging task due to the high variability of prostate anatomic structure. Artifacts such as noise and similar signal intensity of tissues around the prostate boundary inhibit traditional segmentation methods from achieving high accuracy. We investigate both patch-based and holistic (image-to-image) deep-learning methods for segmentation of the prostate. First, we introduce a patch-based convolutional network that aims to refine the prostate contour which provides an initialization. Second, we propose a method for end-to-end prostate segmentation by integrating holistically nested edge detection with fully convolutional networks. Holistically nested networks (HNN) automatically learn a hierarchical representation that can improve prostate boundary detection. Quantitative evaluation is performed on the MRI scans of 250 patients in fivefold cross-validation. The proposed enhanced HNN model achieves a mean ± standard deviation. A Dice similarity coefficient (DSC) of [Formula: see text] and a mean Jaccard similarity coefficient (IoU) of [Formula: see text] are used to calculate without trimming any end slices. The proposed holistic model significantly ([Formula: see text]) outperforms a patch-based AlexNet model by 9% in DSC and 13% in IoU. Overall, the method achieves state-of-the-art performance as compared with other MRI prostate segmentation methods in the literature.

10.
J Vis Exp ; (121)2017 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-28362388

RESUMEN

In many regions of the central nervous systems, such as the fly optic lobes and the vertebrate cortex, synaptic circuits are organized in layers and columns to facilitate brain wiring during development and information processing in developed animals. Postsynaptic neurons elaborate dendrites in type-specific patterns in specific layers to synapse with appropriate presynaptic terminals. The fly medulla neuropil is composed of 10 layers and about 750 columns; each column is innervated by dendrites of over 38 types of medulla neurons, which match with the axonal terminals of some 7 types of afferents in a type-specific fashion. This report details the procedures to image and analyze dendrites of medulla neurons. The workflow includes three sections: (i) the dual-view imaging section combines two confocal image stacks collected at orthogonal orientations into a high-resolution 3D image of dendrites; (ii) the dendrite tracing and registration section traces dendritic arbors in 3D and registers dendritic traces to the reference column array; (iii) the dendritic analysis section analyzes dendritic patterns with respect to columns and layers, including layer-specific termination and planar projection direction of dendritic arbors, and derives estimates of dendritic branching and termination frequencies. The protocols utilize custom plugins built on the open-source MIPAV (Medical Imaging Processing, Analysis, and Visualization) platform and custom toolboxes in the matrix laboratory language. Together, these protocols provide a complete workflow to analyze the dendritic routing of Drosophila medulla neurons in layers and columns, to identify cell types, and to determine defects in mutants.


Asunto(s)
Células Dendríticas/citología , Neuronas/citología , Sinapsis/metabolismo , Animales , Células Dendríticas/metabolismo , Drosophila , Modelos Animales , Neuronas/metabolismo , Terminales Presinápticos
11.
JMIR Med Inform ; 5(1): e2, 2017 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-28213343

RESUMEN

BACKGROUND: As one of the several effective solutions for personal privacy protection, a global unique identifier (GUID) is linked with hash codes that are generated from combinations of personally identifiable information (PII) by a one-way hash algorithm. On the GUID server, no PII is permitted to be stored, and only GUID and hash codes are allowed. The quality of PII entry is critical to the GUID system. OBJECTIVE: The goal of our study was to explore a method of checking questionable entry of PII in this context without using or sending any portion of PII while registering a subject. METHODS: According to the principle of GUID system, all possible combination patterns of PII fields were analyzed and used to generate hash codes, which were stored on the GUID server. Based on the matching rules of the GUID system, an error-checking algorithm was developed using set theory to check PII entry errors. We selected 200,000 simulated individuals with randomly-planted errors to evaluate the proposed algorithm. These errors were placed in the required PII fields or optional PII fields. The performance of the proposed algorithm was also tested in the registering system of study subjects. RESULTS: There are 127,700 error-planted subjects, of which 114,464 (89.64%) can still be identified as the previous one and remaining 13,236 (10.36%, 13,236/127,700) are discriminated as new subjects. As expected, 100% of nonidentified subjects had errors within the required PII fields. The possibility that a subject is identified is related to the count and the type of incorrect PII field. For all identified subjects, their errors can be found by the proposed algorithm. The scope of questionable PII fields is also associated with the count and the type of the incorrect PII field. The best situation is to precisely find the exact incorrect PII fields, and the worst situation is to shrink the questionable scope only to a set of 13 PII fields. In the application, the proposed algorithm can give a hint of questionable PII entry and perform as an effective tool. CONCLUSIONS: The GUID system has high error tolerance and may correctly identify and associate a subject even with few PII field errors. Correct data entry, especially required PII fields, is critical to avoiding false splits. In the context of one-way hash transformation, the questionable input of PII may be identified by applying set theory operators based on the hash codes. The count and the type of incorrect PII fields play an important role in identifying a subject and locating questionable PII fields.

12.
Proc Natl Acad Sci U S A ; 113(16): 4368-73, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27044072

RESUMEN

We report superresolution optical sectioning using a multiangle total internal reflection fluorescence (TIRF) microscope. TIRF images were constructed from several layers within a normal TIRF excitation zone by sequentially imaging and photobleaching the fluorescent molecules. The depth of the evanescent wave at different layers was altered by tuning the excitation light incident angle. The angle was tuned from the highest (the smallest TIRF depth) toward the critical angle (the largest TIRF depth) to preferentially photobleach fluorescence from the lower layers and allow straightforward observation of deeper structures without masking by the brighter signals closer to the coverglass. Reconstruction of the TIRF images enabled 3D imaging of biological samples with 20-nm axial resolution. Two-color imaging of epidermal growth factor (EGF) ligand and clathrin revealed the dynamics of EGF-activated clathrin-mediated endocytosis during internalization. Furthermore, Bayesian analysis of images collected during the photobleaching step of each plane enabled lateral superresolution (<100 nm) within each of the sections.


Asunto(s)
Clatrina/metabolismo , Endocitosis/fisiología , Factor de Crecimiento Epidérmico/metabolismo , Colorantes Fluorescentes/química , Imagenología Tridimensional , Fotoblanqueo , Línea Celular , Humanos , Microscopía Fluorescente/métodos
13.
Mov Disord ; 31(6): 915-23, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26442452

RESUMEN

BACKGROUND: Neuroprotection for Parkinson's disease (PD) remains elusive. Biomarkers hold the promise of removing roadblocks to therapy development. The National Institute of Neurological Disorders and Stroke has therefore established the Parkinson's Disease Biomarkers Program to promote discovery of PD biomarkers for use in phase II and III clinical trials. METHODS: Using a novel consortium design, the Parkinson's Disease Biomarker Program is focused on the development of clinical and laboratory-based biomarkers for PD diagnosis, progression, and prognosis. Standardized operating procedures and pooled reference samples were created to allow cross-project comparisons and assessment of batch effects. A web-based Data Management Resource facilitates rapid sharing of data and biosamples across the research community for additional biomarker projects. RESULTS: Eleven consortium projects are ongoing, seven of which recruit participants and obtain biosamples. As of October 2014, 1,082 participants have enrolled (620 PD, 101 with other causes of parkinsonism, 23 essential tremor, and 338 controls), 1,040 of whom have at least one biosample. Six thousand eight hundred ninety-eight total biosamples are available from baseline, 6-, 12-, and 18-month visits: 1,006 DNA, 1,661 RNA, 1,419 whole blood, 1,382 plasma, 1,200 serum, and 230 cerebrospinal fluid (CSF). Quality control analysis of plasma, serum, and CSF samples indicates that almost all samples are high quality (24 of 2,812 samples exceed acceptable hemoglobin levels). CONCLUSIONS: By making samples and data widely available, using stringent operating procedures based on existing standards, hypothesis testing for biomarker discovery, and providing a resource that complements existing programs, the Parkinson's Disease Biomarker Program will accelerate the pace of PD biomarker research. © 2015 International Parkinson and Movement Disorder Society.


Asunto(s)
Biomarcadores , Estudios Multicéntricos como Asunto , National Institute of Neurological Disorders and Stroke (U.S.) , Enfermedad de Parkinson/diagnóstico , Desarrollo de Programa , Humanos , Estados Unidos
14.
Pain Med ; 17(1): 46-51, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26332923

RESUMEN

OBJECTIVE: Reports of catastrophic neurologic injuries following lumbar transforaminal epidural steroid injections are rare but serious potential complications. The traditional method of performing lumbar transforaminal epidural steroid injections is in the "safe triangle" to avoid contact to the spinal nerve. Some authors advocate an alternative approach by placing the needle inferiorly in a region referred to as "Kambin's triangle" to avoid incurring arteries. This study aimed to determine the location of arteries within the L1-L4 intervertebral foramen in vivo, specifically if they lie within or in close proximity to the "safe triangle" or Kambin's triangle using CT angiograms of the abdomen and pelvis. STUDY DESIGN: The authors retrospectively evaluated the location in vivo of arterial vessels in the intervertebral foramen from L1 to L4 in patients who underwent abdominopelvic CT angiograms for aortic vascular disease. The data were reanalyzed to confirm inter-rater reliability. RESULTS: Arteries were found in both the safe triangle and Kambin's triangle at a statistically significant rate (P < 0.05). CONCLUSIONS: In this group of patients, an artery was found in either the safe triangle or in Kambin's triangle frequently, suggesting the location of these arteries can be quite variable. Physicians performing these procedures should use universal precautions to avoid inadvertent injection into the lumbar spinal arteries and minimize potential complications regardless of the approach.


Asunto(s)
Abdomen/patología , Arterias/cirugía , Vértebras Lumbares/irrigación sanguínea , Vértebras Lumbares/cirugía , Pelvis/patología , Raíces Nerviosas Espinales/patología , Angiografía , Femenino , Humanos , Inyecciones Epidurales/métodos , Masculino , Estudios Retrospectivos
15.
Elife ; 42015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26633880

RESUMEN

The nematode Caenorhabditis elegans possesses a simple embryonic nervous system with few enough neurons that the growth of each cell could be followed to provide a systems-level view of development. However, studies of single cell development have largely been conducted in fixed or pre-twitching live embryos, because of technical difficulties associated with embryo movement in late embryogenesis. We present open-source untwisting and annotation software (http://mipav.cit.nih.gov/plugin_jws/mipav_worm_plugin.php) that allows the investigation of neurodevelopmental events in late embryogenesis and apply it to track the 3D positions of seam cell nuclei, neurons, and neurites in multiple elongating embryos. We also provide a tutorial describing how to use the software (Supplementary file 1) and a detailed description of the untwisting algorithm (Appendix). The detailed positional information we obtained enabled us to develop a composite model showing movement of these cells and neurites in an 'average' worm embryo. The untwisting and cell tracking capabilities of our method provide a foundation on which to catalog C. elegans neurodevelopment, allowing interrogation of developmental events in previously inaccessible periods of embryogenesis.


Asunto(s)
Caenorhabditis elegans/embriología , Caenorhabditis elegans/fisiología , Biología Computacional/métodos , Sistema Nervioso/citología , Sistema Nervioso/embriología , Neuronas/fisiología , Programas Informáticos , Animales , Rastreo Celular/métodos , Curaduría de Datos
17.
Orthop Clin North Am ; 46(2): 293-302, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25771323

RESUMEN

Rotator cuff calcific tendinopathy is a common finding that accounts for about 7% of patients with shoulder pain. There are numerous theories on the pathogenesis of rotator cuff calcific tendinopathy. The diagnosis is confirmed with radiography, MRI or ultrasound. There are numerous conservative treatment options available and most patients can be managed successfully without surgical intervention. Nonsteroidal anti-inflammatory drugs and multiple modalities are often used to manage pain and inflammation; physical therapy can help improve scapular mechanics and decrease dynamic impingement; ultrasound-guided needle aspiration and lavage techniques can provide long-term improvement in pain and function in these patients.


Asunto(s)
Calcinosis , Manejo de la Enfermedad , Manguito de los Rotadores , Tendinopatía , Antiinflamatorios no Esteroideos/uso terapéutico , Calcinosis/complicaciones , Calcinosis/diagnóstico , Calcinosis/terapia , Humanos , Modalidades de Fisioterapia , Tendinopatía/diagnóstico , Tendinopatía/etiología , Tendinopatía/terapia
18.
Nat Protoc ; 9(11): 2555-73, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25299154

RESUMEN

We describe the construction and use of a compact dual-view inverted selective plane illumination microscope (diSPIM) for time-lapse volumetric (4D) imaging of living samples at subcellular resolution. Our protocol enables a biologist with some prior microscopy experience to assemble a diSPIM from commercially available parts, to align optics and test system performance, to prepare samples, and to control hardware and data processing with our software. Unlike existing light sheet microscopy protocols, our method does not require the sample to be embedded in agarose; instead, samples are prepared conventionally on glass coverslips. Tissue culture cells and Caenorhabditis elegans embryos are used as examples in this protocol; successful implementation of the protocol results in isotropic resolution and acquisition speeds up to several volumes per s on these samples. Assembling and verifying diSPIM performance takes ∼6 d, sample preparation and data acquisition take up to 5 d and postprocessing takes 3-8 h, depending on the size of the data.


Asunto(s)
Microscopía/instrumentación , Microscopía/métodos , Animales , Caenorhabditis elegans/embriología , Diagnóstico por Imagen/instrumentación , Diagnóstico por Imagen/métodos , Embrión no Mamífero , Diseño de Equipo , Programas Informáticos , Factores de Tiempo
19.
Phys Med Rehabil Clin N Am ; 25(2): 305-17, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24787335

RESUMEN

Most lumbar disk herniations improve over time with or without medical treatment. Disk herniations and annular tears may not be symptomatic and are shown to exist in patients without any symptoms. In some patients, chronic low back pain may result from the syndrome of internal disk disruption. Treatment of chronic pain of diskal cause can be challenging and have varying results in terms of success. The diagnosis, cause, and treatment options are reviewed in this article.


Asunto(s)
Degeneración del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/complicaciones , Dolor de la Región Lumbar/etiología , Manejo del Dolor/métodos , Fusión Vertebral/métodos , Terapia por Acupuntura/métodos , Corticoesteroides/uso terapéutico , Analgésicos/uso terapéutico , Terapia Conductista/métodos , Dolor Crónico , Terapia Combinada , Electromiografía/métodos , Femenino , Humanos , Inyecciones Espinales , Degeneración del Disco Intervertebral/diagnóstico , Degeneración del Disco Intervertebral/terapia , Desplazamiento del Disco Intervertebral/diagnóstico , Desplazamiento del Disco Intervertebral/terapia , Dolor de la Región Lumbar/fisiopatología , Dolor de la Región Lumbar/terapia , Vértebras Lumbares , Imagen por Resonancia Magnética/métodos , Masculino , Modalidades de Fisioterapia , Pronóstico , Medición de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
20.
Neuron ; 81(4): 830-846, 2014 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-24462039

RESUMEN

How neurons form appropriately sized dendritic fields to encounter their presynaptic partners is poorly understood. The Drosophila medulla is organized in layers and columns and innervated by medulla neuron dendrites and photoreceptor axons. Here, we show that three types of medulla projection (Tm) neurons extend their dendrites in stereotyped directions and to distinct layers within a single column for processing retinotopic information. In contrast, the Dm8 amacrine neurons form a wide dendritic field to receive ∼16 R7 photoreceptor inputs. R7- and R8-derived Activin selectively restricts the dendritic fields of their respective postsynaptic partners, Dm8 and Tm20, to the size appropriate for their functions. Canonical Activin signaling promotes dendritic termination without affecting dendritic routing direction or layer. Tm20 neurons lacking Activin signaling expanded their dendritic fields and aberrantly synapsed with neighboring photoreceptors. We suggest that afferent-derived Activin regulates the dendritic field size of their postsynaptic partners to ensure appropriate synaptic partnership.


Asunto(s)
Activinas/metabolismo , Dendritas/metabolismo , Drosophila melanogaster/metabolismo , Interneuronas/metabolismo , Células Fotorreceptoras de Invertebrados/metabolismo , Sinapsis/metabolismo , Activinas/genética , Animales , Axones/metabolismo , Comunicación Celular , Drosophila melanogaster/genética , Estimulación Luminosa/métodos , Retina/metabolismo , Vías Visuales/fisiología
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