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1.
J Bras Pneumol ; 46(5): e20200226, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32965310

RESUMO

OBJECTIVE: To investigate the diagnostic accuracy of a chest X-ray (CXR) score and of clinical and laboratory data in predicting the clinical course of patients with SARS coronavirus 2 (SARS-CoV-2) infection. METHODS: This is a pilot multicenter retrospective study including patients with SARS-CoV-2 infection admitted to the ERs in three hospitals in Italy between February and March of 2020. Two radiologists independently evaluated the baseline CXR of the patients using a semi-quantitative score to determine the severity of lung involvement: a score of 0 represented no lung involvement, whereas scores of 1 to 4 represented the first (less severe) to the fourth (more severe) quartiles regarding the severity of lung involvement. Relevant clinical and laboratory data were collected. The outcome of patients was defined as severe if noninvasive ventilation (NIV) or intubation was necessary, or if the patient died. RESULTS: Our sample comprised 140 patients. Most of the patients were symptomatic (132/138; 95.7%), and 133/140 patients (95.0%) presented with opacities on CXR at admission. Of the 140 patients, 7 (5.0%) showed no lung involvement, whereas 58 (41.4%), 31 (22.1%), 26 (18.6%), and 18 (12.9%), respectively, scored 1, 2, 3, and 4. In our sample, 66 patients underwent NIV or intubation, 37 of whom scored 1 or 2 on baseline CXR, and 28 patients died. CONCLUSIONS: The severity score based on CXR seems to be able to predict the clinical progression in cases that scored 0, 3, or 4. However, the score alone cannot predict the clinical progression in patients with mild-to-moderate parenchymal involvement (scores 1 and 2).


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pandemias , Pneumonia Viral/diagnóstico por imagem , Radiografia Torácica/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/epidemiologia , Estudos Retrospectivos , Síndrome Respiratória Aguda Grave , Raios X
2.
Ital J Pediatr ; 46(1): 137, 2020 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958069

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19), a highly contagious viral disease has spread from Wuhan, Hubei Province, China to all over the world from its first recognition on December 2019. To date, only a few neonatal early-onset sepsis by SARS-COV-2 has been reported worldwide. CASE PRESENTATION: In this report, we present two seriously ill neonates who were born from mothers with stablished COVID-19 pneumonia. Laboratory tests showed lymphopenia with high LDH and hypocalcemia right after the birth. They had fever for days without responding to antibiotics and despite ruling out other potential causes. Both patients had positive RTPCR for SARS-COV-2 in the second round of testing but the first assay tested was negative. Hydroxychloroquine was used to treat both patients; the first patient was treated with it over a period of 14 days before showing signs of improvement. The second patient responded to the treatment over a period of 5 days. CONCLUSION: Although based on the available evidences, vertical transmission of COVID-19 is less likely, many aspects of pathogenesis and transmission of this novel virus are still unclear. Therefore we cannot rule out the vertical transmission totally. Further investigations are warranted to determine the exact mechanisms and routes of transmission.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/transmissão , Transmissão Vertical de Doença Infecciosa , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/transmissão , Raios X , Adulto , Antivirais/uso terapêutico , Betacoronavirus/genética , Análise Química do Sangue , Infecções por Coronavirus/tratamento farmacológico , Feminino , Humanos , Hidroxicloroquina/uso terapêutico , Recém-Nascido , Irã (Geográfico) , Masculino , Pandemias , Pneumonia Viral/tratamento farmacológico , Gravidez , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Science ; 369(6511): 1568-1569, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32973021
4.
Sci Rep ; 10(1): 15364, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958781

RESUMO

Currently, we witness the severe spread of the pandemic of the new Corona virus, COVID-19, which causes dangerous symptoms to humans and animals, its complications may lead to death. Although convolutional neural networks (CNNs) is considered the current state-of-the-art image classification technique, it needs massive computational cost for deployment and training. In this paper, we propose an improved hybrid classification approach for COVID-19 images by combining the strengths of CNNs (using a powerful architecture called Inception) to extract features and a swarm-based feature selection algorithm (Marine Predators Algorithm) to select the most relevant features. A combination of fractional-order and marine predators algorithm (FO-MPA) is considered an integration among a robust tool in mathematics named fractional-order calculus (FO). The proposed approach was evaluated on two public COVID-19 X-ray datasets which achieves both high performance and reduction of computational complexity. The two datasets consist of X-ray COVID-19 images by international Cardiothoracic radiologist, researchers and others published on Kaggle. The proposed approach selected successfully 130 and 86 out of 51 K features extracted by inception from dataset 1 and dataset 2, while improving classification accuracy at the same time. The results are the best achieved on these datasets when compared to a set of recent feature selection algorithms. By achieving 98.7%, 98.2% and 99.6%, 99% of classification accuracy and F-Score for dataset 1 and dataset 2, respectively, the proposed approach outperforms several CNNs and all recent works on COVID-19 images.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/diagnóstico , Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/diagnóstico , Algoritmos , Betacoronavirus , Aprendizado Profundo , Humanos , Redes Neurais de Computação , Pandemias , Raios X
5.
Artigo em Japonês | MEDLINE | ID: mdl-32963134

RESUMO

AIM: The aim of this work was to evaluate the coincidence between light and X-ray field width in air. BACKGROUND: Light fields are often used for confirmation of irradiation position to superficial tumors and final confirmation of the patient's irradiation position. To guarantee collation by the light field, the light and X-ray fields must coincide. Currently, the light field width is determined mainly by visual evaluation using manual methods, such as use of graph paper and rulers. The light field width is difficult to visually recognize a definite position at the edge of the light field. MATERIALS AND METHODS: We quantified the width of light fields emitted from a linear accelerator using a light probe detector and compared the results with those of X-ray fields. In-air measurements were conducted at the same position in the light field with the light probe detector and X-ray field using an ionization chamber installed in an emptied three-dimensional water phantom. RESULTS: The radiation field in air was approximately 2 mm larger than the light field, and we found some influence of transmission and scattered rays on the penumbra region. Before and after exchanging crosshair sheets, the fields also exhibited differences in uniformity. CONCLUSIONS: The proposed method quantifies the light field using a photodetector and can be used to compare the light field with the X-ray field, conforming a useful tool for evaluating the accuracy of treatment devices in an objective and systematic manner.


Assuntos
Aceleradores de Partículas , Radiometria , Humanos , Imagens de Fantasmas , Radiografia , Raios X
6.
Artigo em Japonês | MEDLINE | ID: mdl-32963140

RESUMO

It is important to optimize the exposure dose when conducting interventional radiology, but optimization is difficult for medical centers to achieve independently. In 2005, we administered a questionnaire on the measurement of dose rates and awareness of exposure reduction when performing percutaneous coronary intervention. Ten years later, we conducted a follow-up survey of the same 31 centers to determine the current situation and identify trends. The results of the survey showed that the mean fluoroscopy dose rate decreased to 55% of the 2005 value, from 28.2 to 15.6 mGy/min, and the mean radiography dose rate decreased to 71% of the 2005 value, from 4.2 to 3.0 mGy/s. Dose rates for both fluoroscopy and radiography decreased by 84% of facilities. The results also indicated greater cooperation by physicians compared to 10 years ago. In particular, there was a considerable increase in the exchange of ideas with physicians regarding exposure, suggesting a stronger level of interest in exposure. The overall score for questionnaire items was 33% higher than that in the previous survey. These results show that in the past 10 years, awareness of exposure reduction has improved, and dose optimization has been a major factor in the downward trend in dose rates in radiography and fluoroscopy.


Assuntos
Intervenção Coronária Percutânea , Radiografia Intervencionista , Angiografia Coronária , Fluoroscopia , Seguimentos , Doses de Radiação , Inquéritos e Questionários , Raios X
7.
Eur J Radiol ; 131: 109236, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32932176

RESUMO

BACKGROUND: The outbreak of COVID-19 has become pandemic. Pediatric population has been less studied than adult population and prompt diagnosis is challenging due to asymptomatic or mild episodes. Radiology is an important complement to clinical and epidemiological features. OBJECTIVE: To establish the most common CXR patterns in children with COVID-19, evaluate interobserver correlation and to discuss the role of imaging techniques in the management of children. MATERIALS AND METHODS: Forty-four patients between 0 and 16 years of age with confirmed SARS-Cov-2 infection and CXR were selected. Two paediatric radiologists independently evaluated the images and assessed the type of abnormality, distribution and evolution when available. RESULTS: Median age was 79.8 months (ranging from 2 weeks to 16 years of age). Fever was the most common symptom (43.5 %). 90 % of CXR showed abnormalities. Peribronchial cuffing was the most common finding (86.3 %) followed by GGOs (50 %). In both cases central distribution was more common than peripheral. Consolidations accounted for 18.1 %. Normal CXR, pleural effusion, and altered cardiomediastinal contour were the least common. CONCLUSION: The vast majority of CXR showed abnormalities in children with COVID-19. However, findings are nonspecific. Interobserver correlation was good in describing consolidations, normal x-rays and GGOs. Imaging techniques have a role in the management of children with known or suspected COVID-19, especially in those with moderate or severe symptoms or with underlying risk factors.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Tórax/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Infecções por Coronavirus/complicações , Feminino , Febre/etiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pandemias , Pneumonia Viral/complicações , Fatores de Risco , Raios X
8.
J Infect Dev Ctries ; 14(7): 750-757, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32794466

RESUMO

INTRODUCTION: The numbers of people infected with SARS-CoV-2 in Indonesia especially in Jakarta as the epicenter continue to rise. Limited published clinical data, scarcity and long turn over time of diagnostic testing put clinician in dilemma to make diagnosis. METHODOLOGY: This is an observational case series study from confirmed COVID-19 patient in our hospital from first case admission on 17 March 30 April, 2020. We collected patient's demography, symptoms, comorbidities, therapy, laboratory, chest x-ray and ECG consecutively. RESULTS: Between 17 March 2020 and 30 April 2020, there were 30 confirmed COVID-19 cases, 16 (53.3%) were male. Clinical symptoms were dyspnea in 22 (73.3%) and dry cough 16 (53.3%). Comorbidities were diabetes in 14 (46.6%), hypertension 10 (33.3%) and Coronary Artery Disease (CAD) in 10 (33.3%) patients respectively. Laboratory findings showed lymphopenia in 21 (70%) patients, increased inflammation marker in Erythrocyte Sedimentation Rate (ESR), C-Reactive Protein (CRP) and Lactate Dehydrogenase (LDH) 21 (70%), 23 (76.6%) and 12 (40%) patients respectively. Twenty-seven (90%) cases had abnormal Chest X-Ray (CXR) and mostly severe 18 (60%). Descriptive finding for images included consolidation 16 (53.3%) and Ground Glass Opacities (GGO) in 10 (33.3%) patients. CONCLUSIONS: Based on our findings, most cases of COVID-19 admitted in secondary referral hospital were already in moderate to severe stages. This is most likely due to late referral from primary care and unspecific clinical features resemblance of other infectious diseases. Inflammation marker and CXR are cost effective findings and can be used as marker to determine further referral.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/etiologia , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/etiologia , Adulto , Idoso , Técnicas de Laboratório Clínico , Comorbidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Diabetes Mellitus/epidemiologia , Eletrocardiografia , Feminino , Humanos , Hipertensão/epidemiologia , Indonésia/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , Radiografia Torácica , Centros de Cuidados de Saúde Secundários/estatística & dados numéricos , Raios X
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(4): 557-565, 2020 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-32840070

RESUMO

Coronavirus disease 2019 (COVID-19) has spread rapidly around the world. In order to diagnose COVID-19 more quickly, in this paper, a depthwise separable DenseNet was proposed. The paper constructed a deep learning model with 2 905 chest X-ray images as experimental dataset. In order to enhance the contrast, the contrast limited adaptive histogram equalization (CLAHE) algorithm was used to preprocess the X-ray image before network training, then the images were put into the training network and the parameters of the network were adjusted to the optimal. Meanwhile, Leaky ReLU was selected as the activation function. VGG16, ResNet18, ResNet34, DenseNet121 and SDenseNet models were used to compare with the model proposed in this paper. Compared with ResNet34, the proposed classification model of pneumonia had improved 2.0%, 2.3% and 1.5% in accuracy, sensitivity and specificity respectively. Compared with the SDenseNet network without depthwise separable convolution, number of parameters of the proposed model was reduced by 43.9%, but the classification effect did not decrease. It can be found that the proposed DWSDenseNet has a good classification effect on the COVID-19 chest X-ray images dataset. Under the condition of ensuring the accuracy as much as possible, the depthwise separable convolution can effectively reduce number of parameters of the model.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Infecções por Coronavirus/diagnóstico por imagem , Aprendizado Profundo , Humanos , Pneumonia Viral/diagnóstico por imagem , Raios X
11.
PLoS Biol ; 18(8): e3000807, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760056

RESUMO

Radiotherapy is a commonly used conditioning regimen for bone marrow transplantation (BMT). Cytotoxicity limits the use of this life-saving therapy, but the underlying mechanisms remain poorly defined. Here, we use the syngeneic mouse BMT model to test the hypothesis that lethal radiation damages tissues, thereby unleashing signals that indiscriminately activate the inflammasome pathways in host and transplanted cells. We find that a clinically relevant high dose of radiation causes severe damage to bones and the spleen through mechanisms involving the NLRP3 and AIM2 inflammasomes but not the NLRC4 inflammasome. Downstream, we demonstrate that gasdermin D (GSDMD), the common effector of the inflammasomes, is also activated by radiation. Remarkably, protection against the injury induced by deadly ionizing radiation occurs only when NLRP3, AIM2, or GSDMD is lost simultaneously in both the donor and host cell compartments. Thus, this study reveals a continuum of the actions of lethal radiation relayed by the inflammasome-GSDMD axis, initially affecting recipient cells and ultimately harming transplanted cells as they grow in the severely injured and toxic environment. This study also suggests that therapeutic targeting of inflammasome-GSDMD signaling has the potential to prevent the collateral effects of intense radiation regimens.


Assuntos
Células da Medula Óssea/efeitos da radiação , Transplante de Medula Óssea , Proteínas de Ligação a DNA/genética , Inflamassomos/efeitos da radiação , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteínas de Ligação a Fosfato/genética , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Proteínas de Ligação a DNA/deficiência , Feminino , Fêmur/citologia , Fêmur/metabolismo , Regulação da Expressão Gênica , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Proteínas de Ligação a Fosfato/deficiência , Piroptose/genética , Piroptose/efeitos da radiação , Transdução de Sinais , Baço/metabolismo , Baço/patologia , Baço/efeitos da radiação , Transplante Isogênico , Irradiação Corporal Total , Raios X
12.
PLoS One ; 15(8): e0238106, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32845905

RESUMO

PURPOSE: Real-time monitoring of physiological changes of tumor tissue during radiation therapy (RT) could improve therapeutic efficacy and predict therapeutic outcomes. Cherenkov radiation is a normal byproduct of radiation deposited in tissue. Previous studies in rat tumors have confirmed a correlation between Cherenkov emission spectra and optical measurements of blood-oxygen saturation based on the tissue absorption coefficients. The purpose of this study is to determine if it is feasible to image Cherenkov emissions during radiation therapy in larger human-sized tumors of pet dogs with cancer. We also wished to validate the prior work in rats, to determine if Cherenkov emissions have the potential to act an indicator of blood-oxygen saturation or water-content changes in the tumor tissue-both of which have been correlated with patient prognosis. METHODS: A DoseOptics camera, built to image the low-intensity emission of Cherenkov radiation, was used to measure Cherenkov intensities in a cohort of cancer-bearing pet dogs during clinical irradiation. Tumor type and location varied, as did the radiation fractionation scheme and beam arrangement, each planned according to institutional standard-of-care. Unmodulated radiation was delivered using multiple 6 MV X-ray beams from a clinical linear accelerator. Each dog was treated with a minimum of 16 Gy total, in ≥3 fractions. Each fraction was split into at least three subfractions per gantry angle. During each subfraction, Cherenkov emissions were imaged. RESULTS: We documented significant intra-subfraction differences between the Cherenkov intensities for normal tissue, whole-tumor tissue, tissue at the edge of the tumor and tissue at the center of the tumor (p<0.05). Additionally, intra-subfraction changes suggest that Cherenkov emissions may have captured fluctuating absorption properties within the tumor. CONCLUSION: Here we demonstrate that it is possible to obtain Cherenkov emissions from canine cancers within a fraction of radiotherapy. The entire optical spectrum was obtained which includes the window for imaging changes in water and hemoglobin saturation. This lends credence to the goal of using this method during radiotherapy in human patients and client-owned pets.


Assuntos
Neoplasias/radioterapia , Raios X , Animais , Cães , Processamento de Imagem Assistida por Computador , Neoplasias/diagnóstico por imagem , Aceleradores de Partículas , Projetos Piloto , Estudos Prospectivos , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X
13.
Artigo em Japonês | MEDLINE | ID: mdl-32814738

RESUMO

Some radiologic patient positioning techniques that can be used for X-ray examinations can be difficult to apply. One method involves using ultra-low-dose X-ray images to confirm positioning. These positioning images are typically discarded and not used for diagnosis. The purpose of this study was to improve the signal-to-noise ratio (SNR) in diagnostic imaging by including these ultra-low-dose positioning images rather than discarding them. To add two images together, we devised a method in which one image is multiplied by the coefficient calculated from its SNR before the addition. The images were dichotomized into a high SNR group and a low SNR group. The images in the high SNR group and the low SNR group were summed. When doing so, the images of the low SNR group were multiplied. There was one maximum SNR point while the SNR was being changed. The maximum SNR of the synthesized images was equal to the value of the square root of the sum of the squares of the two images. The multiplication coefficient, in the case of the maximum SNR, was near 1 when an image agreed with the Poisson distribution; when it did not, it was far from 1. The difference between the calculated values of the hypothetical measurement of the multiplication coefficient was small. In this study, we showed that improving SNR of a diagnostic image could be achieved by adding a positioning image. The multiplication coefficient in the case of the SNR maximum of a synthesized image is calculable. The measurement of a Wiener spectrum is needed for noise evaluation. There can be problems where there is motion after a positioning image is exposed.


Assuntos
Algoritmos , Humanos , Razão Sinal-Ruído , Raios X
14.
Stud Health Technol Inform ; 272: 457-460, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604701

RESUMO

Pneumonia is a severe health problem causing millions of deaths every year. The aim of this study was to develop an advanced deep learning-based architecture to detect pneumonia using chest X-ray images. We utilized a convolutional neural network (CNN) based on VGG16 architecture consisting of 16 fully connected convolutional layers. A total of 5856 high-resolution frontal view chest X-ray images were used for training, validating, and testing the model. The model achieved an accuracy of 96.6%, sensitivity of 98.1%, specificity of 92.4%, precision of 97.2%, and a F1 Score of 97.6%. This indicates that the model has an excellent performance in classifying pneumonia cases and normal cases. We believe, the proposed model will reduce physician workload, expand the performance of pneumonia screening programs, and improve healthcare service.


Assuntos
Aprendizado Profundo , Pneumonia , Humanos , Redes Neurais de Computação , Pneumonia/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador , Raios X
15.
PLoS One ; 15(7): e0235032, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614831

RESUMO

BACKGROUND: This study aimed to evaluate the feasibility of a new biplanar low-dose X-ray device for facial skeletal imaging. METHODS: We evaluated 48 biplanar radiographs from 12 patients (posteroanterior/lateral), originally taken for a scoliosis examination with a biplanar low-dose X-ray device. For this study, the images were further evaluated for the perceptibility of 38 facial skeleton landmarks. To determine the reliability and reproducibility of perceptibility, two independent observers determined the landmarks twice, during a time interval of at least two weeks. RESULTS: Both interoperator and intraoperator reliability were excellent for all landmarks [intraclass correlation coefficient (ICC) > 0.92]. CONCLUSIONS: The biplanar low-dose X-ray device demonstrated good feasibility for precisely assessing the anatomical landmarks of the facial skeleton. Given its excellent precision, the biplanar low-dose X-ray device data sets should be forwarded from the treating orthopedic surgeon or neurosurgeon to the orthodontist or dentist for further assessment in their field.


Assuntos
Ossos Faciais/diagnóstico por imagem , Adolescente , Adulto , Idoso , Estudos de Viabilidade , Humanos , Pessoa de Meia-Idade , Doses de Radiação , Radiografia , Raios X , Adulto Jovem
16.
An Acad Bras Cienc ; 92 Suppl 1: e20190209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32638865

RESUMO

New approaches based on image analysis can assist in phenotyping of biological characteristics, serving as support for decision-making in modern agribusiness. The aim of this study was to propose a method of high-throughput phenotyping of free access for processing of 2D X-ray images of brachiaria grass (Brachiaria ruziziensis cv. Ruziziensis) seeds, as well as correlate the parameters linked to the physiological potential of the seeds. The study was carried out by means of automated analysis of X-ray images of seeds in which a macro, called PhenoXray, was developed, responsible for digital image processing, for which a series of descriptors were obtained. After the X-ray analysis, a germination test was performed on the seeds and, from this, variables related to the physiological quality of the seeds were obtained. The use of the macro PhenoXray allowed large-scale phenotyping of seed X-rays in a simple, rapid, robust, and totally free manner. This study confirmed that the methodology is efficient for obtaining morphometric data and tissue integrity data in Brachiaria ruziziensis seeds and that parameters such as relative density, integrated density, and seed filling are closely related to the physiological attributes of seed quality.


Assuntos
Brachiaria , Germinação , Sementes , Raios X
17.
Proc Natl Acad Sci U S A ; 117(32): 18915-18917, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32723817
19.
Rev. osteoporos. metab. miner. (Internet) ; 12(2): 45-52, abr.-jun. 2020. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-193783

RESUMO

OBJETIVO: Valorar la asociación de las mediciones tridimensionales (3D) derivadas de la absorciometría de rayos X de energía dual (DXA) lumbar con las fracturas osteoporóticas en las vértebras dorsales. MATERIAL Y MÉTODOS: Analizamos retrospectivamente 32 mujeres postmenopáusicas: 16 con fracturas incidentes en las vértebras dorsales y 16 controles sin ningún tipo de fractura. Las DXA lumbares se adquirieron en la visita inicial (es decir, antes del evento de fractura) y se midió la densidad mineral ósea de área (DMOa) en las vértebras L1 a L4. Las mediciones 3D derivadas de la DXA se evaluaron utilizando un software de modelado 3D (3D-SHAPER). La densidad mineral ósea volumétrica (DMOv) se calculó en el hueso trabecular, cortical e integral. También se midió el grosor cortical y la DMO superficial (DMOs) cortical. Las diferencias en las mediciones derivadas de la DXA entre los grupos de fracturados y controles se evaluaron utilizando una prueba t de Student no pareada. También se calculó la razón de probabilidades (OR) y el área bajo la curva característica operativa del receptor (AUC). RESULTADOS: En el presente estudio caso-control ajustado por edad no se encontraron diferencias significativas entre los grupos de fracturados y controles en términos de peso (ρ = 0,44), altura (ρ = 0,25) y DMOa (ρ = 0,11). Sin embargo, sí se encontraron diferencias significativas (ρ < 0,05) en la DMOv integral y trabecular y en la DMOs cortical. La DMOv trabecular en el cuerpo vertebral fue la medida que mejor discriminó entre ambos grupos, con un AUC de 0,733, respecto a 0,682 para la DMOa. CONCLUSIÓN: Este estudio muestra la capacidad de los modelos 3D derivados de la DXA lumbar para discriminar entre sujetos con fracturas incidentes en las vértebras dorsales y controles. Es necesario analizar cohortes mayores para determinar si estas mediciones podrían mejorar la predicción del riesgo de fractura en la práctica clínica


OBJECTIVE: To assess the relation between three-dimensional (3D) measurements obtained by lumbar dual energy X-ray absorptiometry (DXA) and osteoporotic fractures in dorsal vertebrae. MATERIAL AND METHODS: We analysed retrospectively 32 postmenopausal women, allocated to two groups: 16 women in the experimental group, who presented incident fractures of the dorsal vertebrae, and 16 women in the control group, who did not show any type of fracture. Measurements of the (aBMD) of vertebrae L1 through L4 were taken at the initial visit (i.e., prior to the fracture event) by lumbar dual-energy x-ray absorptiometries (DXA). 3D measurements obtained by DXA were evaluated using 3D modelling software (3D-SHAPER). Volumetric bone mineral density (vBMD) was calculated in the trabecular, cortical and integral bone. Cortical thickness and cortical surface BMD (sBMD) were also measured. Differences in measurements derived from the DXA between the experimental and control groups were assessed using an unpaired Student t-test. The odds ratio (OR) and the area under the receiver operating characteristic curve (AUC) were also determined. RESULTS: In the present age-adjusted case-control study, no significant differences were found between the experimental and control groups in terms of weight (ρ = 0.44), height (ρ = 0.25) and aBMD (ρ = 0.11). However, significant differences (ρ < 0.05) were found in the integral and trabecular vBMD and in the cortical sBMD. Trabecular vBMD in the vertebral body was the measure that best discriminated between both groups, with an AUC of 0.733, compared to 0.682 of the aBMD. CONCLUSION: This study shows the ability of 3D models resultant from lumbar DXAs to discern between subjects with incident fractures in the dorsal vertebrae and control subjects. It is necessary to analyse larger cohorts to establish if these measurements could improve the prediction of fracture risk in clinical practice


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Estudos de Casos e Controles , Estudos Retrospectivos , Absorciometria de Fóton , Raios X
20.
Fa Yi Xue Za Zhi ; 36(2): 249-255, 2020 Apr.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32530176

RESUMO

Abstract: Bone age is an important indicator of human growth and development, which can objectively reflect the growth level and maturity of individuals. Traditional manual bone age assessment usually compares the X-ray of the left wrist with the reference standard to obtain the corresponding bone age. This method is time-consuming and its results vary with different observers. In recent years, with the continuous development of computer science, bone age assessment has began to change from traditional manual assessment to automatic assessment. Although there has already been numerous researches on automatic bone age assessment, most of them are still in the experimental stage. This paper reviews related research and progress on automatic bone age assessment at home and abroad in recent years, in order to provide reference and research ideas for relevant researchers.


Assuntos
Determinação da Idade pelo Esqueleto , Humanos , Punho , Raios X
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