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1.
Sensors (Basel) ; 23(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36772599

RESUMEN

Arterial stiffness is a major condition related to many cardiovascular diseases. Traditional approaches in the assessment of arterial stiffness supported by machine learning techniques are limited to the pulse wave velocity (PWV) estimation based on pressure signals from the peripheral arteries. Nevertheless, arterial stiffness can be assessed based on the pressure-strain relationship by analyzing its hysteresis loop. In this work, the capacity of deep learning models based on generative adversarial networks (GANs) to transfer pressure signals from the peripheral arterial region to pressure and area signals located in the central arterial region is explored. The studied signals are from a public and validated virtual database. Compared to other works in which the assessment of arterial stiffness was performed via PWV, in the present work the pressure-strain hysteresis loop is reconstructed and evaluated in terms of classical machine learning metrics and clinical parameters. Least-square GAN (LSGAN) and Wasserstein GAN with gradient penalty (WGAN-GP) adversarial losses are compared, yielding better results with LSGAN. LSGAN mean ± standard deviation of error for pressure and area pulse waveforms are 0.8 ± 0.4 mmHg and 0.1 ± 0.1 cm2, respectively. Regarding the pressure-strain elastic modulus, it is achieved a mean absolute percentage error of 6.5 ± 5.1%. GAN-based deep learning models can recover the pressure-strain loop of central arteries while observing pressure signals from peripheral arteries.


Asunto(s)
Análisis de la Onda del Pulso , Rigidez Vascular , Presión Sanguínea/fisiología , Análisis de la Onda del Pulso/métodos , Presión Arterial , Arterias , Determinación de la Presión Sanguínea/métodos , Rigidez Vascular/fisiología
2.
Artículo en Inglés | MEDLINE | ID: mdl-34891238

RESUMEN

A deep learning technique based on semantic segmentation was implemented into the blood pressure detection points field. Two models were trained and evaluated in terms of a reference detector. The proposed methodology outperforms the reference detector in two of the three classic benchmarks and on signals from a public database that were modified with realistic test maneuvers and artifacts. Both models differentiate regions with valid information and artifacts. So far, no other delineator had shown this capacity.


Asunto(s)
Aprendizaje Profundo , Presión Arterial , Artefactos , Bases de Datos Factuales
3.
Nutrients ; 13(11)2021 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34836396

RESUMEN

Lockdown caused by the COVID-19 pandemic may have influenced feeding behaviour and lifestyle in children and adolescents. The purpose of this study was to analyse feeding behaviour and lifestyle in children and adolescents one year after lockdown by the COVID-19 pandemic in Chile. In this cross-sectional study an online survey was implemented in 1083 parents and caregivers regarding their children's feeding behaviour and lifestyle and sociodemographic background. The results showed that "eat breakfast daily" (89.2%), "not overnight food intake" (69.9%) and "not fast-food intake" (66.0%) were the most frequent reported feeding behaviours, particularly in pre-school children. Respondents declaring healthy feeding behaviours and lifestyle were 23.4 and 23.7%, respectively, with no significant differences by sex. In pre-school children, families with three or fewer members and parents or caregivers with an undergraduate or postgraduate degree reported a significantly better feeding behaviour and lifestyle compared to families with more than three members and parents or caregivers without an undergraduate or postgraduate degree. In conclusion, the pandemic lockdown had a negative impact in lifestyle in children and particularly in adolescents. Healthier feeding behaviour was associated with fewer family members and parents or caregivers with at least an undergraduate degree.


Asunto(s)
Conducta del Adolescente , COVID-19 , Conducta Infantil , Conducta Alimentaria , Estilo de Vida , Cuarentena , Adolescente , Factores de Edad , Niño , Preescolar , Chile , Estudios Transversales , Encuestas sobre Dietas , Dieta Saludable , Familia , Femenino , Preferencias Alimentarias , Humanos , Masculino , Valor Nutritivo , Factores Socioeconómicos , Factores de Tiempo
4.
Sensors (Basel) ; 21(6)2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33808925

RESUMEN

Arterial blood pressure (ABP) is an important vital sign from which it can be extracted valuable information about the subject's health. After studying its morphology it is possible to diagnose cardiovascular diseases such as hypertension, so ABP routine control is recommended. The most common method of controlling ABP is the cuff-based method, from which it is obtained only the systolic and diastolic blood pressure (SBP and DBP, respectively). This paper proposes a cuff-free method to estimate the morphology of the average ABP pulse (ABPM¯) through a deep learning model based on a seq2seq architecture with attention mechanism. It only needs raw photoplethysmogram signals (PPG) from the finger and includes the capacity to integrate both categorical and continuous demographic information (DI). The experiments were performed on more than 1100 subjects from the MIMIC database for which their corresponding age and gender were consulted. Without allowing the use of data from the same subjects to train and test, the mean absolute errors (MAE) were 6.57 ± 0.20 and 14.39 ± 0.42 mmHg for DBP and SBP, respectively. For ABPM¯, R correlation coefficient and the MAE were 0.98 ± 0.001 and 8.89 ± 0.10 mmHg. In summary, this methodology is capable of transforming PPG into an ABP pulse, which obtains better results when DI of the subjects is used, potentially useful in times when wireless devices are becoming more popular.


Asunto(s)
Aprendizaje Profundo , Fotopletismografía , Presión Sanguínea , Determinación de la Presión Sanguínea , Demografía , Humanos
5.
Pediatr Transplant ; 22(2)2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29453782

RESUMEN

Collateral circulation secondary to liver cirrhosis may cause the development of large PSSs that may steal flow from the main portal circulation. It is important to identify these shunts prior to, or during the transplant surgery because they might cause an insufficient portal flow to the implanted graft. There are few reports of "steal flow syndrome" cases in pediatrics, even in biliary atresia patients that may have portal hypoplasia as an associated malformation. We present a 12-month-old female who received an uneventful LDLT from her mother, and the GRWR was 4.8. During the early post-operative period, she became hemodynamically unstable, developed ascites, and altered LFT. The post-operative ultrasound identified reversed portal flow, finding a non-anatomical PSS. A 3D CT scan confirmed the presence of a mesocaval shunt through the territory of the right gonadal vein, draining into the right iliac vein, with no portal inflow into the liver. The patient was re-operated, and the shunt was ligated. An intraoperative Doppler ultrasound showed adequate portal inflow after the procedure; the patient evolved satisfactorily and was discharged home on day number 49. The aim was to report a case of post-operative steal syndrome in a pediatric recipient due to a mesocaval shunt not diagnosed during the pretransplant evaluation.


Asunto(s)
Atresia Biliar/cirugía , Circulación Colateral , Trasplante de Hígado , Hígado/irrigación sanguínea , Atresia Biliar/fisiopatología , Femenino , Humanos , Vena Ilíaca/fisiología , Lactante , Donadores Vivos , Vena Porta/fisiología
6.
Curr Opin Organ Transplant ; 22(2): 135-141, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28151808

RESUMEN

PURPOSE OF REVIEW: One of the most important challenges in the intestinal (ITx) and multivisceral transplant (MVTx) is to achieve a successful abdominal wall closure. RECENT FINDINGS: A tension-free primary closure should be our aim. In most of the cases, we need to perform a component separation technique, alone or combined, to the use of a synthetic mesh. If those options are not feasible, the abdominal wall composite vascularized allograft transplant (AW-CVA) utilizing direct orthotopic vascularization can be considered. The nonvascularized abdominal rectus fascia has also become an alternative method used worldwide, proving to be simple and well tolerated procedure. Furthermore, the use of the AW has been recently proposed as a new tool for a sentinel monitoring of the intestinal or pancreas allograft. SUMMARY: There are different validated options for abdominal wall closure following intestinal transplantation. The long-term benefits of transplanting the abdominal wall, full or partial thickness and vascularized or nonvascularised, were shown. New developments might help to expand their applications in different areas such as reconstructive surgery and immunology.


Asunto(s)
Pared Abdominal/cirugía , Aloinjertos Compuestos/trasplante , Intestinos/trasplante , Procedimientos de Cirugía Plástica/métodos , Humanos
7.
HPB (Oxford) ; 18(3): 221-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27017161

RESUMEN

BACKGROUND: This multicentre, randomized clinical trial assessed the safety and effectiveness of the EVARREST™ Fibrin Sealant Patch (FP) in treating parenchymal bleeding following anatomic and non-anatomic liver resections. METHODS: One hundred and two patients were stratified according to the type of hepatic resection (anatomic/non-anatomic), and randomized (1:1) after identification of an appropriate bleeding site, to FP vs Standard of Care (SoC, manual compression ± topical haemostat). The primary endpoint was haemostasis at 4 min from bleeding site identification with no re-bleeding requiring re-treatment. RESULTS: The FP was superior in achieving haemostasis at 4 min (96%, 48/50) to SoC (46%, 24/52; p < 0.001). Stratification for resection type showed treatment differences for primary endpoint for anatomic (24/25 FP vs 13/23 SoC; p = 0.001) and non-anatomic liver resections (24/25FP vs 11/29 SoC; p < 0.001). Adverse events related to the study procedure were reported in 40/50 patients (80%) in the FP group and 43/52 patients (83%) in the SoC group. One (2%) adverse event (infected intra-abdominal fluid collection) was possibly related to study treatment. CONCLUSION: This clinical trial confirms that the FP is safe and highly effective in controlling parenchymal bleeding following hepatectomy regardless of the type of resection. ClinicalTrials.gov NCT01993888.


Asunto(s)
Adhesivo de Tejido de Fibrina/uso terapéutico , Técnicas Hemostáticas , Hemostáticos/uso terapéutico , Hepatectomía/efectos adversos , Hemorragia Posoperatoria/prevención & control , Adhesivos Tisulares/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Australia , Transfusión Sanguínea , Procedimientos Quirúrgicos Electivos , Femenino , Adhesivo de Tejido de Fibrina/efectos adversos , Técnicas Hemostáticas/efectos adversos , Hemostáticos/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda , Hemorragia Posoperatoria/etiología , Estudios Prospectivos , Factores de Tiempo , Adhesivos Tisulares/efectos adversos , Resultado del Tratamiento , Reino Unido , Estados Unidos , Adulto Joven
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