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1.
Artif Intell Med ; 103: 101784, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32143791

RESUMO

BACKGROUND AND OBJECTIVE: The measurement of carotid intima media thickness (CIMT) in ultrasound images can be used to detect the presence of atherosclerotic plaques. Usually, the CIMT estimation strategy is semi-automatic, since it requires: (1) a manual examination of the ultrasound image for the localization of a region of interest (ROI), a fast and useful operation when only a small number of images need to be measured; and (2) an automatic delineation of the CIM region within the ROI. The existing efforts for automating the process have replicated the same two-step structure, resulting in two consecutive independent approaches. In this work, we propose a fully automatic single-step approach based on semantic segmentation that allows us to segment the plaque and to estimate the CIMT in a fast and useful manner for large data sets of images. METHODS: Our single-step approach is based on densely connected convolutional neural networks (DenseNets) for semantic segmentation of the whole image. It has two remarkable characteristics: (1) it avoids ROI definition, and (2) it captures multi-scale contextual information in the complete image interpretation, due to the concatenation of feature maps carried out in DenseNets. Once the input image is segmented, a straightforward method for CIMT estimation and plaque detection is applied. RESULTS: The proposed method has been validated with a large data set (REGICOR) of more than 8000 images, corresponding to two territories of the carotid artery: common carotid artery (CCA) and bulb. Among them, a subset of 331 images has been used to evaluate the performance of semantic segmentation (≈90% for train, ≈10% for test). The experimental results demonstrated that our method outperforms other deep models and shallow approaches found in the literature. In particular, our CIMT estimation reaches a correlation coefficient of 0.81, and a CIMT mean error of 0.02 and 0.06 mm in CCA and Bulb images, respectively. Furthermore, the accuracy for plaque detection is 96.45% and 78.09% in CCA and Bulb, respectively. To test the generalization power, the method has also been tested with another data set (NEFRONA) that includes images acquired with different equipment. CONCLUSIONS: The validation carried out demonstrates that the proposed method is accurate and objective for both plaque detection and CIMT measurement. Moreover, the robustness and generalization capacity of the method have been proven with two different data sets.


Assuntos
Espessura Intima-Media Carotídea , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Placa Aterosclerótica/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Ultrassonografia
2.
Nefrología (Madrid) ; 39(1): 29-34, ene.-feb. 2019. graf
Artigo em Inglês | IBECS | ID: ibc-181906

RESUMO

The Global Burden of Disease (GBD) study measures the health of populations worldwide and by country on an annual basis and aims at helping guide public policy on health issues. The GBD estimates for Spain in 2016 and recent trends in mortality and morbidity from 2006 to 2016 were recently published. According to these estimates, chronic kidney disease was the 8th cause of death in Spain in 2016. Among the top ten causes of death, chronic kidney disease was the fastest growing from 2006 to 2016, after Alzheimer disease. At the current pace of growth, chronic kidney disease is set to become the second cause of death in Spain, after Alzheimer disease, by 2100. Additionally, among major causes of death, chronic kidney disease also ranked second only to Alzheimer as the fastest growing cause of Years Lived with Disability (YLDs) and Disability Adjusted Life Years (DALYs). Public resources devoted to prevention, care and research on kidney disease should be in line with both its current and future burden


El estudio Global Burden of Disease (GBD) mide la salud de las poblaciones en todo el mundo y en cada país de forma annual, y tiene como objetivo ayudar a orientar las políticas públicas sobre cuestiones de salud. Recientemente se publicaron las estimaciones GBD 2016 para España y las tendencias recientes en mortalidad y morbilidad de 2006 a 2016. Según estas estimaciones, la enfermedad renal crónica fue la octava causa de muerte en España en 2016. Entre las 10 principales causas de muerte, la enfermedad renal crónica fue la que más creció entre 2006 y 2016, después de la enfermedad de Alzheimer. Al ritmo actual de crecimiento, la enfermedad renal crónica se convertirá en la segunda causa de muerte en España, después del Alzheimer, hacia el 2100. Además, entre las principales causas de muerte, la enfermedad renal crónica también ocupa el segundo lugar después del Alzheimer como la que más creció en años vividos con discapacidad (AVD) y en años de vida ajustados por discapacidad (AVAD). Los recursos públicos dedicados a la prevención, atención e investigación de la enfermedad renal deberían estar en línea con su carga actual y futura


Assuntos
Humanos , Insuficiência Renal Crônica/mortalidade , Sociedades Médicas , Espanha/epidemiologia , Causas de Morte
3.
Nefrologia (Engl Ed) ; 39(1): 29-34, 2019.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30503082

RESUMO

The Global Burden of Disease (GBD) study measures the health of populations worldwide and by country on an annual basis and aims at helping guide public policy on health issues. The GBD estimates for Spain in 2016 and recent trends in mortality and morbidity from 2006 to 2016 were recently published. According to these estimates, chronic kidney disease was the 8th cause of death in Spain in 2016. Among the top ten causes of death, chronic kidney disease was the fastest growing from 2006 to 2016, after Alzheimer disease. At the current pace of growth, chronic kidney disease is set to become the second cause of death in Spain, after Alzheimer disease, by 2100. Additionally, among major causes of death, chronic kidney disease also ranked second only to Alzheimer as the fastest growing cause of Years Lived with Disability (YLDs) and Disability Adjusted Life Years (DALYs). Public resources devoted to prevention, care and research on kidney disease should be in line with both its current and future burden.


Assuntos
Carga Global da Doença/estatística & dados numéricos , Insuficiência Renal Crônica/mortalidade , Doença de Alzheimer/epidemiologia , Causas de Morte , Humanos , Nefrologia , Anos de Vida Ajustados por Qualidade de Vida , Insuficiência Renal Crônica/epidemiologia , Sociedades Médicas , Espanha/epidemiologia
4.
Nephron ; 133(4): 232-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27434035

RESUMO

BACKGROUND: The quantification of proteinuria with the protein to creatinine ratio (PCR) is influenced by the excretion of creatinine, which, in turn, varies according to muscle mass and hence, to gender. AIMS: To assess the difference between urine PCR and 24-hour urine proteinuria in men and women and to provide a formula to overcome bias caused by gender. METHODS: Four hundred and forty four CKD patients were randomly divided into 2 groups: 70% were used to develop the models, while the remaining 30% were reserved to validate the formula. Epidemiological data were analyzed with chi-square and Student's t tests. Association between 24-hour proteinuria and PCR was studied with Spearman coefficient in men and women separately. Multivariate analysis was used to find variables predictive of disagreement between the 24-hour urine protein and the PCR. Equations to predict 24-hour proteinuria from PCR for men and women were plotted and validated. RESULTS: Disagreement between 24-hour proteinuria and PCR was more pronounced in men (2.16 and 1.64 g in mean, respectively) than in women (2.00 and 2.06 g in mean, respectively). Age and gender were independent predictors of disagreement. Gender-specific equations for predicting 24-hour proteinuria were: males: 24-hour proteinuria = 1.3350*exp0.9108*ln(PCR); females: 24-hour proteinuria = 1.0068*exp0.9030*ln(PCR). CONCLUSIONS: Estimation of proteinuria with the PCR improves accuracy if gender-specific equations are used. Use of the PCR without correction for gender leads to the underestimation of proteinuria in men and overestimation in women.


Assuntos
Creatinina/urina , Proteinúria/urina , Fatores Sexuais , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória
5.
Nefrología (Madr.) ; 36(1): 10-18, ene.-feb. 2016. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-149504

RESUMO

El hiperparatiroidismo secundario (HPTS) es una complicación habitual en pacientes con enfermedad renal crónica que se caracteriza por unos niveles elevados de hormona paratiroidea (PTH) y una serie de anomalías en el metabolismo mineral-óseo. En pacientes con HPTS, el tratamiento con paricalcitol, un activador selectivo de los receptores de la vitamina D, ha demostrado reducir los niveles de PTH con mínimas variaciones del calcio y del fósforo séricos. El efecto clásico de paricalcitol es el de mediador en la homeostasis mineral y ósea. Sin embargo, estudios recientes han indicado que los beneficios del tratamiento con paricalcitol van más allá de la reducción de PTH, por ejemplo, ocasionando efectos positivos en la enfermedad cardiovascular y en la supervivencia. El objetivo del presente trabajo es revisar los estudios más significativos sobre los llamados efectos pleiotrópicos del tratamiento con paricalcitol en pacientes con ERC (AU)


Secondary hyperparathyroidism (SHPT) is a common complication in patients with chronic kidney disease (CKD) that is characterised by elevated parathyroid hormone (PTH) levels and a series of bone-mineral metabolism anomalies. In patients with SHPT, treatment with paricalcitol, a selective vitamin D receptor activator, has been shown to reduce PTH levels with minimal serum calcium and phosphorus variations. The classic effect of paricalcitol is that of a mediator in mineral and bone homeostasis. However, recent studies have suggested that the benefits of treatment with paricalcitol go beyond PTH reduction and, for instance, it has a positive effect on cardiovascular disease and survival. The objective of this study is to review the most significant studies on the so-called pleiotropic effects of paricalcitol treatment in patients with CKD (AU)


Assuntos
Humanos , Vitamina D/farmacocinética , Hiperparatireoidismo Secundário/tratamento farmacológico , Insuficiência Renal Crônica/complicações , Conservadores da Densidade Óssea/farmacocinética , Hormônio Paratireóideo/análise , Calcificação Vascular/tratamento farmacológico , Proteinúria/tratamento farmacológico
6.
Nefrologia ; 36(1): 10-8, 2016.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26705959

RESUMO

Secondary hyperparathyroidism (SHPT) is a common complication in patients with chronic kidney disease (CKD) that is characterised by elevated parathyroid hormone (PTH) levels and a series of bone-mineral metabolism anomalies. In patients with SHPT, treatment with paricalcitol, a selective vitamin D receptor activator, has been shown to reduce PTH levels with minimal serum calcium and phosphorus variations. The classic effect of paricalcitol is that of a mediator in mineral and bone homeostasis. However, recent studies have suggested that the benefits of treatment with paricalcitol go beyond PTH reduction and, for instance, it has a positive effect on cardiovascular disease and survival. The objective of this study is to review the most significant studies on the so-called pleiotropic effects of paricalcitol treatment in patients with CKD.


Assuntos
Ergocalciferóis/uso terapêutico , Hiperparatireoidismo Secundário/tratamento farmacológico , Insuficiência Renal Crônica/complicações , Ergocalciferóis/efeitos adversos , Humanos , Hiperparatireoidismo Secundário/etiologia , Minerais , Hormônio Paratireóideo , Fósforo
9.
Nefrología (Madr.) ; 35(1): 28-41, ene.-feb. 2015. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-133193

RESUMO

El déficit de vitamina D se asocia a distintas patologías, siendo especialmente significativa con la morbimortalidad en pacientes con enfermedad renal crónica (ERC). La pérdida progresiva de la función renal conduce a una reducción de calcitriol y alteración de la homeostasis de calcio, fósforo, FGF-23 y PTH, entre otros, los cuales influyen a su vez sobre la activación del receptor de vitamina D (RVD) y el desarrollo de hiperparatiroidismo secundario (HPS). El RVD media las acciones biológicas tanto de la vitamina D como de sus análogos sintéticos, actuando sobre distintos genes; existe una estrecha asociación entre niveles bajos de calcitriol y la prevalencia del HPS. Así, la activación de los RVD y la restricción de fósforo, entre otros, desempeñan un papel importante en el tratamiento de la «alteración óseo-mineral asociada a la ERC». La Sociedad Española de Nefrología, dada la uniforme e importante asociación con mortalidad y niveles altos de fósforo, aconseja su normalización, así como la de los niveles de calcidiol. Igualmente considera que, aparte de la utilización de activadores selectivos/no selectivos de RVD para la prevención y tratamiento del HPS, se podría asegurar la activación de los RVD en pacientes en diálisis, con vitamina D nativa o incluso bajas dosis de paricalcitol, independientemente de la PTH, dado que algunos estudios de cohortes y un metaanálisis reciente han observado una asociación entre el tratamiento con vitamina D activa y la disminución de la mortalidad en pacientes con ERC. En general, se considera que es razonable utilizar toda esta información para individualizar la toma de decisiones (AU)


Vitamin D deficiency has been linked to many different pathologies, especially with morbimortality in patients with chronic kidney disease. The progressive loss of renal function leads to calcitriol deficiency and homeostatic changes in calcium, phosphorus, FGF-23 and PTH, among others. All these changes can also influence vitamin D receptor (VDR) activation and the development of secondary hyperparathyroidism (SHPT). The biologic actions of both vitamin D and its synthetic analogues are mediated by binding to the same VDR, acting on different genes. There is a narrow relationship between low levels of calcitriol and SHPT. The combined approach of VDR activation and phosphate restriction, among others, plays an important role in the early treatment of the chronic kidney disease-mineral and bone disorder (CKD-MBD). The Spanish Society of Nephrology, in order to reduce the uniform and significant association with CKD-associated mortality, calcidiol and high phosphate levels suggests normalization of phosphate as well as calcidiol levels in both CKD and dialysis patients. Moreover, it considers that, in addition to selective/non selective activation of VDR for the prevention and treatment of SHPT, VDR could be activated in dialysis patients by native vitamin D or even low paricalcitol doses, independently of PTH levels, as some cohort studies and a recent metaanalysis have found an association between treatment with active vitamin D and decreased mortality in patients with CKD. In general it is considered reasonable to use all this information to individualise decision making (AU)


Assuntos
Humanos , Vitamina D/uso terapêutico , Deficiência de Vitamina D/fisiopatologia , Receptores de Calcitriol/deficiência , Insuficiência Renal Crônica/fisiopatologia , Diálise Renal/efeitos adversos , Fósforo/análise , Calcitriol/uso terapêutico , Calcificação Vascular/fisiopatologia , Densidade Óssea , Calcimiméticos/farmacocinética
10.
Nefrologia ; 35(1): 28-41, 2015.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-25611831

RESUMO

Vitamin D deficiency has been linked to many different pathologies, especially with morbimortality in patients with chronic kidney disease. The progressive loss of renal function leads to calcitriol deficiency and homeostatic changes in calcium, phosphorus, FGF-23 and PTH, among others. All these changes can also influence vitamin D receptor (VDR) activation and the development of secondary hyperparathyroidism (SHPT). The biologic actions of both vitamin D and its synthetic analogues are mediated by binding to the same VDR, acting on different genes. There is a narrow relationship between low levels of calcitriol and SHPT. The combined approach of VDR activation and phosphate restriction, among others, plays an important role in the early treatment of the chronic kidney disease-mineral and bone disorder (CKD-MBD). The Spanish Society of Nephrology, in order to reduce the uniform and significant association with CKD-associated mortality, calcidiol and high phosphate levels suggests normalization of phosphate as well as calcidiol levels in both CKD and dialysis patients. Moreover, it considers that, in addition to selective/non selective activation of VDR for the prevention and treatment of SHPT, VDR could be activated in dialysis patients by native vitamin D or even low paricalcitol doses, independently of PTH levels, as some cohort studies and a recent metaanalysis have found an association between treatment with active vitamin D and decreased mortality in patients with CKD. In general it is considered reasonable to use all this information to individualise decision making.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/etiologia , Ergocalciferóis/uso terapêutico , Receptores de Calcitriol/fisiologia , Insuficiência Renal Crônica/complicações , Vitamina D/fisiologia , Animais , Calcifediol/sangue , Calcimiméticos/uso terapêutico , Calcitriol/uso terapêutico , Distúrbio Mineral e Ósseo na Doença Renal Crônica/tratamento farmacológico , Ensaios Clínicos como Assunto , Avaliação Pré-Clínica de Medicamentos , Substituição de Medicamentos , Ergocalciferóis/farmacologia , Fator de Crescimento de Fibroblastos 23 , Humanos , Hiperparatireoidismo Secundário/tratamento farmacológico , Hiperparatireoidismo Secundário/etiologia , Fosfatos/sangue , Ratos , Receptores de Calcitriol/agonistas , Diálise Renal , Insuficiência Renal Crônica/metabolismo , Vitamina D/uso terapêutico
17.
Nefrologia ; 31 Suppl 1: 3-32, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21468161
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