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1.
Ultrasound Obstet Gynecol ; 63(3): 350-357, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37774112

RESUMEN

OBJECTIVE: Pre-eclampsia (PE) is a serious complication of pregnancy associated with maternal and fetal morbidity and mortality. As current prediction models have limitations and may not be applicable in resource-limited settings, we aimed to develop a machine-learning (ML) algorithm that offers a potential solution for developing accurate and efficient first-trimester prediction of PE. METHODS: We conducted a prospective cohort study in Mexico City, Mexico to develop a first-trimester prediction model for preterm PE (pPE) using ML. Maternal characteristics and locally derived multiples of the median (MoM) values for mean arterial pressure, uterine artery pulsatility index and serum placental growth factor were used for variable selection. The dataset was split into training, validation and test sets. An elastic-net method was employed for predictor selection, and model performance was evaluated using area under the receiver-operating-characteristics curve (AUC) and detection rates (DR) at 10% false-positive rates (FPR). RESULTS: The final analysis included 3050 pregnant women, of whom 124 (4.07%) developed PE. The ML model showed good performance, with AUCs of 0.897, 0.963 and 0.778 for pPE, early-onset PE (ePE) and any type of PE (all-PE), respectively. The DRs at 10% FPR were 76.5%, 88.2% and 50.1% for pPE, ePE and all-PE, respectively. CONCLUSIONS: Our ML model demonstrated high accuracy in predicting pPE and ePE using first-trimester maternal characteristics and locally derived MoM. The model may provide an efficient and accessible tool for early prediction of PE, facilitating timely intervention and improved maternal and fetal outcome. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Eficiencia de un enfoque de aprendizaje automático para la predicción de la preeclampsia en un país de ingresos medios OBJETIVO: La preeclampsia (PE) es una complicación grave del embarazo asociada a morbilidad y mortalidad materna y del feto. Dado que los modelos de predicción actuales tienen limitaciones y pueden no ser aplicables en situaciones con recursos limitados, se propuso desarrollar un algoritmo de aprendizaje automático (AA) que ofrezca una solución con potencial para desarrollar una predicción precisa y eficiente de la PE en el primer trimestre. MÉTODOS: Se realizó un estudio de cohorte prospectivo en Ciudad de México para desarrollar un modelo de predicción de la PE pretérmino (PEp) en el primer trimestre utilizando AA. Para la selección de variables se utilizaron las características maternas y los múltiplos de la mediana (MdM) obtenidos localmente para la presión arterial media, el índice de pulsatilidad de la arteria uterina y el factor de crecimiento placentario sérico. El conjunto de datos se dividió en subconjuntos de datos de entrenamiento, de validación y de test estadístico. Se empleó un método de red elástica para la selección de predictores, y el rendimiento del modelo se evaluó mediante el área bajo la curva de características operativas del receptor (ABC) y las tasas de detección (TD) con tasas de falsos positivos (TFP) del 10%. RESULTADOS: El análisis final incluyó a 3050 mujeres embarazadas, de las cuales 124 (4,07%) desarrollaron PE. El modelo de AA mostró una buena eficiencia, con un ABC de 0,897, 0,963 y 0,778 para la PEp, la PE de aparición temprana (PEat) y cualquier tipo de PE (todas las PE), respectivamente. Las TD con TFP del 10% fueron del 76,5%, 88,2% y 50,1% para la PEp, PEat y todas las PE, respectivamente. CONCLUSIONES: Nuestro modelo de AA demostró una alta precisión en la predicción de la PEp y la PEat utilizando características maternas del primer trimestre y MdM calculados localmente. El modelo puede proporcionar una herramienta eficiente y accesible para la predicción temprana de la PE, facilitando la intervención oportuna y la mejora de los resultados maternos y del feto.


Asunto(s)
Preeclampsia , Recién Nacido , Embarazo , Femenino , Humanos , Preeclampsia/diagnóstico , Factor de Crecimiento Placentario , Estudios Prospectivos , Biomarcadores , Primer Trimestre del Embarazo
2.
RSC Adv ; 13(20): 13862-13879, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37181503

RESUMEN

In this work, we present the synthesis of TiO2 photocatalysts modified with different % mol of tin using the sol-gel method. The materials were characterized using different analytical techniques. The Rietveld refinement, XPS, Raman and UV-Vis techniques confirm the substitution of tin in the TiO2 structural lattice due to changes in crystal lattice parameters, the low-energy shift of the Sn 3d5/2 orbital, generation of oxygen vacancies and the decreased band gap and increased BET surface area. The material with 1 mol% tin shows superior catalytic activity compared to the references for the degradation of 40 ppm 4-chlorophenol (3 hours of reaction) and 50 ppm phenol (6 hours of reaction). Reactions fit pseudo first order kinetics in both instances. The increase in photodegradation efficiency was attributed to the generation of energy levels below the TiO2 conduction band caused by the incorporation of 1% mol of tin, oxygen vacancies, and the heterojunction formed between the brookite-anatase-rutile, causing inhibition of the recombination of the electron (e-) and hole (h+) photogenerated species. The easy synthesis, low cost and increased photodegradation efficiency of the photocatalyst with 1 mol% tin have the potential to favor the remediation of recalcitrant compounds in water.

3.
RSC Adv ; 12(39): 25711-25721, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36199326

RESUMEN

In this work the effect of noble metal on the photodegradation of 2,4-dichlorophenoxyacetic acid herbicide using TiO2 as support was studied. The metals and concentration were: Rh, Ru, Pt and Au and 1, 0.98, 1.89, and 1.91 wt% respectively. Rhodium was taken as reference for this experiment. The samples were characterized by X-Ray Diffraction (XRD), UV-vis absorption spectra, N2 physisorption (BET Specific Surface Area), High Annular Angle Analysis Darkfield (HAADF) and Transmission Electron Microscopy Scanning (STEM), H2 chemisorption, optical emission spectroscopy with inductive coupling plasma analysis (ICP-OES), solid fluorescence, X-ray Photoelectron Spectroscopy (XPS) and OH quantification. The presence of the anatase crystalline phase was mostly confirmed in all samples. The band gap decreased with the presence of metal (from 3.24 to 2.92 eV). The specific area was a function of the metal particle size. The metal particle diameter showed the following sequence Pt > Ru > Au > Rh. By XPS, TiO2 does not manifest changes in oxidation states, but when impregnated with metals, only Pt shows the highest abundance of any oxidized state (Pt2+). The presence of metal reveals less electron-hole recombination compared with titanium oxide. The results of photocatalytic activity showed that Pt and Rh are the two metals with the highest mineralization (99.0 and 98.3%, respectively).

4.
Ultrasound Obstet Gynecol ; 59(1): 76-82, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34672382

RESUMEN

OBJECTIVE: Mortality in pregnancy due to coronavirus disease 2019 (COVID-19) is a current health priority in developing countries. Identification of clinical and sociodemographic risk factors related to mortality in pregnant women with COVID-19 could guide public policy and encourage such women to accept vaccination. We aimed to evaluate the association of comorbidities and socioeconomic determinants with COVID-19-related mortality and severe disease in pregnant women in Mexico. METHODS: This is an ongoing nationwide prospective cohort study that includes all pregnant women with a positive reverse-transcription quantitative polymerase chain reaction result for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from the Mexican National Registry of Coronavirus. The primary outcome was maternal death due to COVID-19. The association of comorbidities and socioeconomic characteristics with maternal death was explored using a log-binomial regression model adjusted for possible confounders. RESULTS: There were 176 (1.35%) maternal deaths due to COVID-19 among 13 062 consecutive SARS-CoV-2-positive pregnant women. Maternal age, as a continuous (adjusted relative risk (aRR), 1.08 (95% CI, 1.05-1.10)) or categorical variable, was associated with maternal death due to COVID-19; women aged 35-39 years (aRR, 3.16 (95% CI, 2.34-4.26)) or 40 years or older (aRR, 4.07 (95% CI, 2.65-6.25)) had a higher risk for mortality, as compared with those aged < 35 years. Other clinical risk factors associated with maternal mortality were pre-existing diabetes (aRR, 2.66 (95% CI, 1.65-4.27)), chronic hypertension (aRR, 1.75 (95% CI, 1.02-3.00)) and obesity (aRR, 2.15 (95% CI, 1.46-3.17)). Very high social vulnerability (aRR, 1.88 (95% CI, 1.26-2.80)) and high social vulnerability (aRR, 1.49 (95% CI, 1.04-2.13)) were associated with an increased risk of maternal mortality, while very low social vulnerability was associated with a reduced risk (aRR, 0.47 (95% CI, 0.30-0.73)). Being poor or extremely poor were also risk factors for maternal mortality (aRR, 1.53 (95% CI, 1.09-2.15) and aRR, 1.83 (95% CI, 1.32-2.53), respectively). CONCLUSION: This study, which comprises the largest prospective consecutive cohort of pregnant women with COVID-19 to date, has confirmed that advanced maternal age, pre-existing diabetes, chronic hypertension, obesity, high social vulnerability and low socioeconomic status are risk factors for COVID-19-related maternal mortality. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
COVID-19/epidemiología , Muerte Materna/estadística & datos numéricos , Complicaciones Infecciosas del Embarazo/epidemiología , Vulnerabilidad Social , Adulto , Estudios de Cohortes , Comorbilidad , Femenino , Humanos , Mortalidad Materna , México , Pobreza , Embarazo , Nacimiento Prematuro/epidemiología , Estudios Prospectivos
5.
Ultrasound Obstet Gynecol ; 59(2): 202-208, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34664753

RESUMEN

OBJECTIVE: In addition to the lungs, the placenta and the endothelium can be affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) are markers of endothelial dysfunction and could potentially serve as predictors of severe coronavirus disease 2019 (COVID-19). We aimed to investigate the association of serum concentrations of sFlt-1 and PlGF with the severity of COVID-19 in pregnancy. METHODS: This was a prospective cohort study carried out in a tertiary care hospital in Mexico City, Mexico. Symptomatic pregnant women with a positive reverse-transcription quantitative polymerase chain reaction test for SARS-CoV-2 infection who fulfilled the criteria for hospitalization were included. The primary outcome was severe pneumonia due to COVID-19. Secondary outcomes were intensive care unit (ICU) admission, viral sepsis and maternal death. sFlt-1 levels were expressed as multiples of the median (MoM). The association between sFlt-1 and each adverse outcome was explored by logistic regression analysis, adjusted for gestational age for outcomes occurring in more than five patients, and the predictive performance was assessed by receiver-operating-characteristics-curve analysis. RESULTS: Among 113 pregnant women with COVID-19, higher sFlt-1 MoM was associated with an increased probability of severe pneumonia (adjusted odds ratio (aOR), 1.817 (95% CI, 1.365-2.418)), ICU admission (aOR, 2.195 (95% CI, 1.582-3.047)), viral sepsis (aOR, 2.318 (95% CI, 1.407-3.820)) and maternal death (unadjusted OR, 5.504 (95% CI, 1.079-28.076)). At a 10% false-positive rate, sFlt-1 MoM had detection rates of 45.2%, 66.7%, 83.3% and 100% for severe COVID-19 pneumonia, ICU admission, viral sepsis and maternal death, respectively. PlGF values were similar between women with severe and those with non-severe COVID-19 pneumonia. CONCLUSION: sFlt-1 MoM is higher in pregnant women with severe COVID-19 and has the capability to predict serious adverse pregnancy events, such as severe pneumonia, ICU admission, viral sepsis and maternal death. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
COVID-19 , Unidades de Cuidados Intensivos/estadística & datos numéricos , Neumonía Viral , Complicaciones Infecciosas del Embarazo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre , Adulto , COVID-19/sangre , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/terapia , Estudios de Cohortes , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Femenino , Edad Gestacional , Humanos , México/epidemiología , Mortalidad , Placenta/metabolismo , Placenta/fisiopatología , Factor de Crecimiento Placentario/sangre , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Neumonía Viral/etiología , Embarazo , Complicaciones Infecciosas del Embarazo/sangre , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/terapia , SARS-CoV-2/aislamiento & purificación , Índice de Severidad de la Enfermedad
6.
Ultrasound Obstet Gynecol ; 57(2): 224-231, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33320401

RESUMEN

OBJECTIVE: There are limited, unmatched data reporting low complication rates in pregnant women with coronavirus disease 2019 (COVID-19). The aim of this study was to compare COVID-19-related outcomes between pregnant and non-pregnant women after adjusting for potential risk factors for severe outcomes. METHODS: Data were obtained from the COVID-19 National Data Registry of Mexico, which is an ongoing prospective cohort of people of any age with clinically suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and admitted to 475 monitoring hospitals. This study included pregnant and non-pregnant women of reproductive age (15-45 years) with COVID-19 confirmed by reverse transcription polymerase chain reaction. To adjust for underlying risk factors, propensity score matching was conducted for chronic obstructive pulmonary disease, asthma, smoking, hypertension, cardiovascular disease, obesity, diabetes, chronic renal disease, immunosuppression, age, language, nationality and level of health insurance. The primary outcome was death. Secondary outcomes were pneumonia, intubation and intensive care unit (ICU) admission. RESULTS: The cohort comprised 5183 pregnant and 175 905 non-pregnant women with COVID-19. The crude (unmatched) rates of death, pneumonia, intubation and ICU admission in pregnant compared with non-pregnant women were 1.5% vs 1.5%, 9.9% vs 6.5%, 8.1% vs 9.9% and 13.0% vs 6.9%, respectively. After propensity score matching (5183 pregnant and 5183 non-pregnant matched women), pregnant women had a higher odds of death (odds ratio (OR), 1.84; 95% CI, 1.26-2.69), pneumonia (OR, 1.86; 95% CI, 1.60-2.16) and ICU admission (OR, 1.86; 95% CI, 1.41-2.45) than non-pregnant women, but similar odds of intubation (OR, 0.93; 95% CI, 0.70-1.25). CONCLUSION: After adjusting for background demographic and medical factors, pregnancy is a risk factor for death, pneumonia and ICU admission in SARS-CoV-2-infected women of reproductive age. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
COVID-19/mortalidad , Neumonía/etiología , Complicaciones Infecciosas del Embarazo/mortalidad , Complicaciones Infecciosas del Embarazo/virología , Adolescente , Adulto , COVID-19/diagnóstico , COVID-19/virología , Estudios de Casos y Controles , Comorbilidad , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , México/epidemiología , Persona de Mediana Edad , Mortalidad , Pandemias , Neumonía/virología , Embarazo , Puntaje de Propensión , Estudios Prospectivos , Factores de Riesgo , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Adulto Joven
7.
Ultrasound Obstet Gynecol ; 56(4): 516-521, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32068928

RESUMEN

OBJECTIVE: To evaluate the impact of fetal endoscopic tracheal occlusion (FETO) on improving survival of fetuses with severe left-sided congenital diaphragmatic hernia (CDH), as compared with contemporaneous cases managed expectantly during pregnancy, in a country with suboptimal neonatal management. METHODS: In this prospective cohort study, consecutive fetuses with isolated left-sided CDH, normal karyotype and severe pulmonary hypoplasia (defined as liver herniation and observed/expected lung-to-head circumference ratio below 26%) were selected for FETO at less than 32 weeks of gestation in a single tertiary referral center in Queretaro, Mexico. Postnatal outcome (survival up to 28 days after birth) was compared between fetuses treated with FETO and contemporaneous cases with similar lung size managed expectantly during pregnancy. RESULTS: Twenty-five fetuses with isolated severe left-sided CDH treated with FETO were matched individually with 25 cases managed expectantly during pregnancy. Endotracheal placement of the balloon was performed successfully on the first attempt in all cases. The median gestational age (GA) at balloon placement was 29.1 (range, 25.6-31.8) weeks and 34.1 (range, 30.0-36.1) weeks at balloon removal. There were no technical problems with the introduction or removal of the balloon in any cases. The median GA at delivery was significantly lower in the group treated with FETO than in those managed expectantly (35.3 vs 37.7 weeks; P = 0.04). The survival rate was significantly higher in the group treated with FETO than in those without fetal intervention (32% vs 0%; P < 0.001). CONCLUSION: In settings with suboptimal neonatal management, FETO was associated with improved neonatal survival in fetuses with isolated left-sided CDH and severe pulmonary hypoplasia. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Resultado de supervivencia en una hernia diafragmática congénita grave del lado izquierdo, con y sin oclusión traqueal endoscópica fetal en un país con un tratamiento neonatal subóptimo OBJETIVO: Evaluar el impacto de la oclusión traqueal endoscópica fetal (OTEF) en la mejora de la supervivencia de los fetos con hernia diafragmática congénita (HDC) grave del lado izquierdo, en comparación con los casos actuales tratados como embarazo gestante, en un país con un tratamiento neonatal subóptimo. MÉTODOS: En este estudio prospectivo de cohortes, se seleccionaron fetos consecutivos con HDC aislada del lado izquierdo, cariotipo normal e hipoplasia pulmonar grave (definida como hernia hepática y una proporción observada/esperada de la circunferencia pulmonar-cabeza inferior al 26%) para una OTEF antes de las 32 semanas de gestación, en un único centro de medicina especializada terciaria en Querétaro (México). El resultado postnatal (supervivencia hasta los 28 días después del nacimiento) se comparó entre fetos tratados con OTEF y los casos contemporáneos con tamaño pulmonar similar, tratados como embarazo gestante. RESULTADOS: Veinticinco fetos con HDC grave aislada del lado izquierdo que habían sido tratados con OTEF fueron emparejados individualmente con 25 casos tratados como embarazo gestante. La colocación endotraqueal del globo se realizó con éxito en el primer intento en todos los casos. La mediana de la edad gestacional (EG) en el momento de la colocación del globo fue de 29,1 (rango, 25,6-31,8) semanas y 34,1 (rango, 30,0-36,1) semanas cuando se retiró el globo. En ningún caso hubo problemas técnicos con la introducción o la retirada del globo. La mediana de la EG en el momento del parto fue significativamente menor en el grupo tratado con OTEF que en el grupo tratado como gestante (35,3 vs 37,7 semanas; P=0,04). La tasa de supervivencia fue significativamente más alta en el grupo tratado con OTEF que en los casos sin intervención fetal (32% vs 0%; P<0,001). CONCLUSIÓN: En los entornos con un tratamiento neonatal subóptimo, la OTEF se asoció con una mejora de la supervivencia neonatal en los fetos con HDC aislada del lado izquierdo y con hipoplasia pulmonar grave. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Oclusión con Balón/mortalidad , Fetoscopía/mortalidad , Hernias Diafragmáticas Congénitas/cirugía , Pulmón/anomalías , Tráquea/cirugía , Oclusión con Balón/métodos , Cefalometría , Femenino , Fetoscopía/métodos , Feto/diagnóstico por imagen , Feto/embriología , Feto/cirugía , Hernias Diafragmáticas Congénitas/embriología , Humanos , Recién Nacido , Pulmón/embriología , México , Embarazo , Atención Prenatal/estadística & datos numéricos , Estudios Prospectivos , Tasa de Supervivencia , Tráquea/embriología , Resultado del Tratamiento , Ultrasonografía Prenatal , Espera Vigilante/estadística & datos numéricos
8.
Water Sci Technol ; 80(5): 911-919, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31746798

RESUMEN

In this work, we describe the morphological, electronic and catalytic properties of support TiO2-CeO2-ZrO2, prepared by sol-gel method, which was impregnated with copper at 5 and 10% by weight, in order to obtain efficient catalysts in the catalytic wet air oxidation (CWAO) of 2-cp. The catalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM-EDS), UV-Vis diffuse reflectance spectroscopy (DRS) and nitrogen physisorption by the Brunauer-Emmett-Teller (BET) method. The activity of the materials used in this study revealed that without the presence of Cu, the SCO2 is low and with a content of 10% this metal shows the best catalytic behaviour; conversely, a reaction mechanism is proposed that describes the complete oxidation of 2-cp in this case.


Asunto(s)
Clorofenoles , Cobre , Catálisis , Oxidación-Reducción
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