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1.
Eur J Radiol ; 140: 109769, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33992980

RESUMEN

OBJECTIVE: This study aimed to investigate the diagnostic performance of radiomics features derived from coronary computed tomography angiography (CCTA) in the identification of ischemic coronary stenosis plaque using invasive fractional flow reserve (FFR) as the reference standard. MATERIALS AND METHODS: 174 plaques of 149 patients (age: 62.21 ±â€¯8.47 years, 96 males) with at least one lesion stenosis degree between 30 % and 90 % were retrospectively included. Stenosis degree and plaque characteristics were recorded, and a conventional multivariate logistic model was established. Over 1000 radiomics features of the plaque were derived from CCTA images. The plaques were randomly divided into training set (n = 139) and validation set (n = 35). A random forest model was built. The area under the curve (AUC) of the models was compared. RESULTS: Fifty-eight radiomics features were correlated with functionally significant stenosis (p <  0.05), wherein 56 features had an AUC of >0.6. NCP volume, NRS, remodeling index, and spotty calcification were included in the conventional model. Ultimately, 14 features were integrated to build the radiomics model. The AUC showed an improvement: 0.71 vs 0.82 for the training set and 0.70 vs 0.77 for the validation set (conventional model and radiomics model, respectively); however, it was not statistically significant (p =  0.58). CONCLUSION: The radiomics analysis of plaques showed improvement compared with conventional plaques assessment in identifying hemodynamically significant coronary stenosis. The statistical advancement of machine learning for plaques to predict hemodynamic stenosis with a noninvasive approach still needs further studies on a large-scale dataset.


Asunto(s)
Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Anciano , Angiografía por Tomografía Computarizada , Angiografía Coronaria , Estenosis Coronaria/diagnóstico por imagen , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estándares de Referencia , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
2.
Neurol India ; 67(4): 979-982, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31512618

RESUMEN

The eye is a vital sense organ and plays a vital role in conveying the underlying physical and mental state of wellbeing of an individual. A comprehensive examination of the eye is often required in patients presenting with systemic complaints. Many endocrine disorders have characteristic manifestations pertaining to the eye, the classical being the exophthalmos in thyrotoxicosis. However, a cursory eye evaluation may lead to the identification of early features that can help in the diagnosis of other endocrine disorders. This is more common in cases of pituitary mass lesions, who often present with the functional hormonal alterations rather than the visual symptoms. The definitive therapy during the late stages of the disease leads to persisting visual disabilities and affects the quality of life. Hence, the endocrinologists and ophthalmologists need to be aware of various ophthalmic features in the pituitary disorders. In this review, we highlight the eye signs in pituitary disorders, along with a brief description of uncommon ocular-pituitary syndromes.


Asunto(s)
Oftalmopatías/diagnóstico , Enfermedades de la Hipófisis/diagnóstico , Trastornos de la Visión/diagnóstico , Oftalmopatías/etiología , Humanos , Enfermedades de la Hipófisis/complicaciones , Trastornos de la Visión/etiología
3.
Brain Struct Funct ; 223(1): 519-533, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29124351

RESUMEN

Two-photon Ca2+ imaging has become a popular approach for monitoring neuronal population activity with cellular or subcellular resolution in vivo. This approach allows for the recording of hundreds to thousands of neurons per animal and thus leads to a large amount of data to be processed. In particular, manually drawing regions of interest is the most time-consuming aspect of data analysis. However, the development of automated image analysis pipelines, which will be essential for dealing with the likely future deluge of imaging data, remains a major challenge. To address this issue, we developed NeuroSeg, an open-source MATLAB program that can facilitate the accurate and efficient segmentation of neurons in two-photon Ca2+ imaging data. We proposed an approach using a generalized Laplacian of Gaussian filter to detect cells and weighting-based segmentation to separate individual cells from the background. We tested this approach on an in vivo two-photon Ca2+ imaging dataset obtained from mouse cortical neurons with differently sized view fields. We show that this approach exhibits superior performance for cell detection and segmentation compared with the existing published tools. In addition, we integrated the previously reported, activity-based segmentation into our approach and found that this combined method was even more promising. The NeuroSeg software, including source code and graphical user interface, is freely available and will be a useful tool for in vivo brain activity mapping.


Asunto(s)
Calcio/metabolismo , Procesamiento Automatizado de Datos/métodos , Neuronas/citología , Neuronas/fisiología , Algoritmos , Animales , Mapeo Encefálico , Tamaño de la Célula , Procesamiento Automatizado de Datos/instrumentación , Procesamiento de Imagen Asistido por Computador , Masculino , Ratones , Ratones Endogámicos C57BL , Distribución Normal , Óptica y Fotónica , Programas Informáticos
4.
Am J Transl Res ; 8(2): 246-69, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27158324

RESUMEN

Alzheimer's disease (AD) is the most common underlying cause of dementia, and novel drugs for its treatment are needed. Of the different theories explaining the development and progression of AD, "amyloid hypothesis" is the most supported by experimental data. This hypothesis states that the cleavage of amyloid precursor protein (APP) leads to the formation of amyloid beta (Aß) peptides that congregate with formation and deposition of Aß plaques in the frontal cortex and hippocampus. Risk factors including neurotransmitter modulation, chronic inflammation, metal-induced oxidative stress and elevated cholesterol levels are key contributors to the disease progress. Current therapeutic strategies abating AD progression are primarily based on anti-acetylcholinesterase (AChE) inhibitors as cognitive enhancers. The AChE inhibitor, donepezil, is proven to strengthen cognitive functions and appears effective in treating moderate to severe AD patients. N-Methyl-D-aspartate receptor antagonist, memantine, is also useful, and its combination with donepezil demonstrated a strong stabilizing effect in clinical studies on AD. Nonsteroidal anti-inflammatory drugs delayed the onset and progression of AD and attenuated cognitive dysfunction. Based upon epidemiological evidence and animal studies, antioxidants emerged as potential AD preventive agents; however, clinical trials revealed inconsistencies. Pharmacokinetic and pharmacodynamic profiling demonstrated pleiotropic functions of the hypolipidemic class of drugs, statins, potentially contributing towards the prevention of AD. In addition, targeting the APP processing pathways, stimulating neuroprotective signaling mechanisms, using the amyloid anti-aggregants and Aß immunotherapy surfaced as well-tested strategies in reducing the AD-like pathology. Overall, this review covers mechanism of inducing the Aß formation, key risk factors and major therapeutics prevalent in the AD treatment nowadays. It also delineates the need for novel screening approaches towards identifying drugs that may prevent or at least limit the progression of this devastating disease.

5.
J Stroke Cerebrovasc Dis ; 24(11): 2555-60, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26277293

RESUMEN

BACKGROUND: Moyamoya disease or syndrome (MMD or MMS) is a cerebrovascular disease characterized by stenosis or occlusion of the distal portion of the internal carotid arteries, with ultimate spread to the proximal portion of the anterior cerebral arteries and middle cerebral arteries (MCAs). In the present study, we wanted to evaluate the usefulness of conventional computed tomography (CT) and axial magnetic resonance (MR) T2-weighted imaging (T2WI) for the examination of horizontal segments of the MCAs (ie, M1 segments) in patients diagnosed with MMD or MMS. METHODS: This study enrolled 29 patients (n = 11 men; n = 18 women), who underwent conventional CT and/or MR T2WI. CT angiography, MR angiography, or digital subtraction angiography was used as a reference. CT and MR imaging data were reviewed by 2 experienced radiologists, who analyzed and recorded stenosis or occlusions of the M1 segments. We performed statistical analyses to compare the diagnostic accuracy of both techniques on M1 segments in MMD or MMS. RESULTS: Fifty-three steno-occlusive changes of M1 segments were revealed by angiography in the 29 patients. T2W-MRI allowed the identification of moyamoya vessels with 100% success rate. Stenosis and occlusion of M1 segments were better visualized on axial T2W-MRI compared to conventional CT (94.59% versus 71.43%; P = .008). CONCLUSIONS: Our study showed that conventional CT and axial T2W-MRI could be used to identify the steno-occlusive changes of the horizontal segment of the MCA in MMD or MMS, which may have a significant impact on the accurate diagnosis of this disease at its early stage.


Asunto(s)
Arteria Cerebral Media/diagnóstico por imagen , Arteria Cerebral Media/patología , Enfermedad de Moyamoya/patología , Adulto , Bases de Datos Bibliográficas/estadística & datos numéricos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
6.
Inflammation ; 38(5): 1777-86, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25787883

RESUMEN

Fucoidan is a sulfated polysaccharide found mainly in various species of brown algae and brown seaweed. Here, we investigated the effects of low-molecular-weight (LMW) fucoidan (4 kDa) on interleukin-1beta (IL-1ß)-stimulated rheumatoid arthritis fibroblast-like synoviocyte (RAFLS). 3-[4,5-Dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay and annexin V/propidium iodide assay were used to assess cell viability and apoptosis, respectively. Transwell assay was performed to evaluate cell invasion. Reverse transcription polymerase chain reaction, Western blot, and enzyme-linked immunosorbent assay analysis was done to measure gene expression and secretion. Nuclear factor-kappa B (NF-κB) DNA binding activity was determined by electrophoretic mobility shift assay. LMW fucoidan dose-dependently inhibited the viability and induced apoptosis of IL-1ß-treated RAFLS. Fucoidan attenuated IL-1ß-induced invasion of RAFLS and decreased the expression and secretion of metalloproteinase (MMP)-1, MMP-3, and MMP-9. Fucoidan suppressed NF-κB binding activity, p65 nuclear translocation, and IκB-α degradation in IL-1ß-stimulated RAFLS. Additionally, IL-1ß-induced phosphorylation of p38 but not ERK or JNK was significantly impaired by fucoidan treatment. LMW fucoidan reduces the viability, survival, and invasiveness of IL-1ß-treated RAFLS, which is associated with inhibition of NF-κB and p38 activation. LMW fucoidan may have therapeutic potential in the treatment of rheumatoid arthritis.


Asunto(s)
Apoptosis/efectos de los fármacos , Artritis Reumatoide/tratamiento farmacológico , Supervivencia Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Interleucina-1beta/farmacología , Polisacáridos/farmacología , Membrana Sinovial/efectos de los fármacos , Apoptosis/fisiología , Artritis Reumatoide/patología , Supervivencia Celular/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Fibroblastos/patología , Humanos , Interleucina-1beta/uso terapéutico , Polisacáridos/uso terapéutico , Membrana Sinovial/patología
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