Ammonium depletion associated with the COVID-19 pandemic in the Mexican Caribbean.

The Mexican Caribbean contributes significantly to Mexico's gross national product. The number of tourists declined from 16.7 million in 2019 to 8.8 million in 2020 due to the COVID-19 pandemic, with a rapid recovery of 13.5 million in 2021. Wastewater discharge is the primary contamination source associated with the tourism sector's demand for goods and services. Water quality could improve due to fewer tourists arriving during the COVID-19 sanitary emergency. This study aimed to quantify ammonium concentrations at eleven locations to evaluate water quality during the sanitary restriction due to the pandemic in the Mexican Caribbean. The ammonium concentrations were 85 % (Nov-2019), 89 % (Feb-2020), and 86 % (Feb-2021) higher than in Nov-2020, where six of the eleven sampled stations were below the detection limit (0.15 µM). Lower ammonium concentrations coincide with the sanitary restriction period and a decrease in affluent tourists.

Performance of machine-learning approach for prediction of pre-eclampsia in a middle-income country.

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.

Regulatory Mechanisms of Muscle Mass: The Critical Role of Resistance Training in Children and Adolescent.

Muscle mass and strength are subjected to several regulations. We found endocrine signals such as growth hormone, insulin-like growth factor 1, testosterone, thyroid hormones, and glucocorticoids among them. Neural inputs also influence muscle development, modulating mass and strength. Among the external stimuli that modulate these muscular features is physical training such as resistance and endurance training. Specifically, resistance training can mediate an increase in muscle mass by hypertrophy in adults, but the effects in children and adolescents are full of myths for most of the population. However, the evidence shows that the impact of resistance training on children and adolescents is clear and provides a wide range of benefits. However, qualified professionals must be available since exercise prescription and subsequent supervision must follow this population's abilities, needs, and interests.

Consensus and recommendations on vaginal-cuff Brachytherapy of the Spanish Brachytherapy Groups of SEOR and SEFM.

PURPOSE/OBJECTIVE(S): On October 5, 2018, a meeting of the Spanish Society of Radiation Oncology (SEOR) Brachytherapy Group was held, in collaboration with the Spanish Society of Medical Physics (SEFM), with the aim of preparing a consensus document on postoperative vaginal-cuff brachytherapy (VCBT). MATERIALS/METHODS: A survey including 42 questions was sent to Spanish Radiation Oncology Centres before the meeting. The survey items included: experience in VCBT, technique indications, previous patient preparation, applicator type, implant procedure, computerized tomography (CT) simulation, definition of target volumes and organs at risk (OAR), dose prescription, fractionation, treatment planning, dosimetric parameters and constraints to OAR. Thirty-three centres answered the survey. Statistical analysis of the survey considered that there was consensus when there was ≥ 85% of agreement related to a survey item, otherwise an item with < 85% of agreement would be discussed during the meeting to reach consensus. RESULTS: The results of the survey are reported here. The mean number of patients treated per centre in 2017 was 52 ± 41 (range 7-175), and the mean number of procedures per centre was 175 ± 150 (range 24-701).There was consensus on: the indications, applicator type, the OAR to be considered, the prescription point, standardisation and dosimetric quality parameters. There was no consensus on: patient preparation for the implant, the need for performing CT simulation and the frequency, the length of the vagina to be treated, if CTV should be delimited, the definition of the clinical target volume, fractionation, overall EQD2, active source length, separation between dwelling stepping source positions, if considering the uniformity/maximum values for dwelling stepping sources, the optimization mode, and the limiting doses to the OAR. After presenting the results of the survey, the consensus meeting discussion focused on the issues for which there was no consensus. CONCLUSION: A consensus document on postoperative VCBT of the Spanish Brachytherapy Groups of SEOR-SEFM was elaborated.

Dexmedetomidine metabolic clearance is not affected by fat mass in obese patients.

BACKGROUND: Obesity has been associated with reduced dexmedetomidine clearance, suggesting impaired hepatic function or reduced hepatic blood flow. The aim of this study was to clarify the effect of obesity in dexmedetomidine metabolic clearance. METHODS: Forty patients, ASA I-III, 18-60 yr old, weighing 47-126 kg, scheduled for abdominal laparoscopic surgery, were enrolled. Anaesthetic agents (propofol, remifentanil, and dexmedetomidine) were dosed based on lean body weight measured by dual X-ray absorptiometry. Serial venous samples were drawn during and after dexmedetomidine infusion. A pharmacokinetic analysis was undertaken using non-linear mixed-effect models. In the modelling approach, the total body weight, lean body weight, and adjusted body weight were first tested as size descriptors for volumes and clearances. Hepatic blood flow, liver histopathology, liver enzymes, and gene expression of metabolic enzymes (UGT2B10 and UGT1A4) were tested as covariates of dexmedetomidine metabolic clearance. A decrease in NONMEM objective function value (ΔOFV) of 3.84 points, for an added parameter, was considered significant at the 0.05 level. RESULTS: A total of 637 dexmedetomidine serum samples were obtained. A two-compartmental model scaled to measured lean weight adequately described the dexmedetomidine pharmacokinetics. Liver blood flow was a covariate for dexmedetomidine clearance (ΔOFV=-5.878). Other factors, including fat mass, histopathological damage, and differential expression of enzymes, did not affect the dexmedetomidine clearance in the population studied (ΔOFV<3.84). CONCLUSIONS: We did not find a negative influence of obesity in dexmedetomidine clearance when doses were adjusted to lean body weight. Liver blood flow showed a significant effect on dexmedetomidine clearance. CLINICAL TRIAL REGISTRATION: NCT02557867.

Exogenous lipid pneumonia related to long-term use of Vicks VapoRub® by an adult patient: a case report.

BACKGROUND: Use of petroleum-based over the counter remedies such as Vicks VapoRub to alleviate symptoms of rhinitis is common and can be effective, but carries under-appreciated risks of adverse side effects. In this case report we highlight Exogenous Lipoid Pneumonia (ELP), an uncommon condition that results from accumulation of exogenous lipids in the alveoli, as an adverse side effect of long-term Vicks VapoRub use. CASE PRESENTATION: We present the case of an 85-year-old female patient with ELP apparently due to continuous application of Vicks VapoRub® to her nostrils to alleviate chronic rhinitis. She was diagnosed incidentally via chest radiograph and computed tomography (CT) scan done as follow up to finding elevated C-reactive Protein during a routine exam. The CT scan revealed a pulmonary consolidation in the lower lobe of the right lung with fat density combined with low density areas associated with focal ground-glass opacities. The patient was advised to discontinue use of petroleum-based products, and was prescribed intranasal corticosteroids for her rhinitis. Follow up 2 years later showed that the lipid consolidation had diminished in size by approximately 10 %. CONCLUSION: Physicians must be aware that ELP can develop as a result of long-term application of petroleum-based oils and ointments to the nose and discourage such use of these products. Patients who have used petroleum-based products in this way should be screened for ELP. CT scan is the best imaging modality for establishing the diagnosis. The treatment of this condition is not well defined, but, as shown in this case, the size of the lipid mass can decrease after use of petroleum based substances is discontinued.

Dismenorrea membranácea durante la menarquia / Membranous dysmenorrhea during menarche

La dismenorrea membranosa se caracteriza por dolor menstrual acompañado de la expulsión de la mucosa endometrial en forma de grandes fragmentos, e incluso en una única pieza, con la forma del molde de la cavidad uterina. Se presenta el caso de una paciente con expulsión de un gran molde de endometrio durante la menarquia. Se presentan las imágenes del molde endometrial íntegro de la cavidad uterina y el estudio anatomopatológico.

Membranous dysmenorrheal consist of menstrual pain accompanied by the expulsion of endometrial mucosa in the form of large fragments or even in one piece with the shape of the uterine cavity. We present the case of a patient with expulsion of endometrial during menarche. The pictures of endometrial piece, the shape of the uterine cavity and anatomo-pathological study has presented.

Drought impact on forest carbon dynamics and fluxes in Amazonia.

In 2005 and 2010 the Amazon basin experienced two strong droughts, driven by shifts in the tropical hydrological regime possibly associated with global climate change, as predicted by some global models. Tree mortality increased after the 2005 drought, and regional atmospheric inversion modelling showed basin-wide decreases in CO2 uptake in 2010 compared with 2011 (ref. 5). But the response of tropical forest carbon cycling to these droughts is not fully understood and there has been no detailed multi-site investigation in situ. Here we use several years of data from a network of thirteen 1-ha forest plots spread throughout South America, where each component of net primary production (NPP), autotrophic respiration and heterotrophic respiration is measured separately, to develop a better mechanistic understanding of the impact of the 2010 drought on the Amazon forest. We find that total NPP remained constant throughout the drought. However, towards the end of the drought, autotrophic respiration, especially in roots and stems, declined significantly compared with measurements in 2009 made in the absence of drought, with extended decreases in autotrophic respiration in the three driest plots. In the year after the drought, total NPP remained constant but the allocation of carbon shifted towards canopy NPP and away from fine-root NPP. Both leaf-level and plot-level measurements indicate that severe drought suppresses photosynthesis. Scaling these measurements to the entire Amazon basin with rainfall data, we estimate that drought suppressed Amazon-wide photosynthesis in 2010 by 0.38 petagrams of carbon (0.23-0.53 petagrams of carbon). Overall, we find that during this drought, instead of reducing total NPP, trees prioritized growth by reducing autotrophic respiration that was unrelated to growth. This suggests that trees decrease investment in tissue maintenance and defence, in line with eco-evolutionary theories that trees are competitively disadvantaged in the absence of growth. We propose that weakened maintenance and defence investment may, in turn, cause the increase in post-drought tree mortality observed at our plots.

Evaluation of climatic factors on the yield and chemical composition of the essential oil of Myrocarpus frondosus.

The species Myrocarpus frondosus is native to southern Brazil, and it is known as cabreúva. It is a large tree, and its wood is used as a reservoir for distilled spirits, especially Cachaça. In this pioneering work, the essential oil was extracted monthly from the leaves of M. frondosus, for a period of 1 year. The essential oil was extracted by using hydrodistillation and the determination of the chemical composition of essential oil was performed by using the chromatographic techniques GC-FID and GC-MS. Thirty-three compounds were identified in the essential oil and bicyclogermacrene was the major compound. Through multivariate analysis, it was determined that ß-caryophyllene, limonene and terpinen-4-ol were directly proportional to climatic factors. The yield of the oil was directly proportional to temperature and radiation.

Factores de crecimiento, variables antropométricas maternas y tamaño de recién nacidos de término / Insulin, cortisol, IGF, IGFBP-3 and maternal anthropometric variables in full term newborns

Introduction: Fetal growth is a physiological phenomenon involving maternal, placentary and fetal factors. Objective: To analyze growth factors and maternal anthropometric variables in full-term newborns (NB) and compare them to their size. Patients and Methods: 138 newborns, 37-41 gestational weeks, sorted according to size in low, normal and large for gestational age. Umbilical cord blood was measured for: ELISA, insulin, cortisol, IGF, IGFBP-3. Results: A statistically significant difference was seen between maternal weight at the beginning and end of pregnancy, and BMI (body mass index) at the beginning of pregnancy with the size of the NB (p < 0.001). There was no significant difference between growth factors and NB size. Conclusion: Insulin, Cortisol, IGF1, IGFBP-3 do not show statistically significant differences with the size of a newborn, although the mean value of growth factors in normal and large NB for gestational age, were twice than mean values in low for gestational age newborns. There is a positive, statistically significant correlation between the size of the newborn, and the size of the mother, weight at the beginning and end of the pregnancy and the Body Mass index of the mother at the beginning of the pregnancy.

Introducción: El crecimiento fetal es un fenómeno fisiológico complejo en el que intervienen factores maternos, placentarios y fetales. Objetivo: Analizar factores de crecimiento y variables antropométricas maternas en recién nacidos (RN) de término y compararlos con el tamaño de los RN. Pacientes y Método: Estudio prospectivo, descriptivo, transversal, que incluyó a 138 RN entre 37 y 41 semanas, clasificados según tamaño en PEG, AEG y GEG. En sangre de cordón se midió por ELISA, Insulina, cortisol, IGF-1 e IGFBP-3. Resultados: Hubo diferencia estadísticamente significativa (p < 0,01) entre: peso materno al inicio, peso materno al término e índice de masa corporal (IMC) al inicio de la gestación con el tamaño del RN. Hubo correlación positiva entre las variables antropométricas maternas y el peso del RN (p < 0,001). No hubo diferencia significativa entre los factores de crecimiento y el tamaño de los RN. Conclusión: Insulina, cortisol, IGF-1 e IGFBP-3 no muestran diferencias estadísticamente significativas según el tamaño de RN, aunque las medianas de los factores de crecimiento analizados en RN AEG y GEG duplican los valores de los RN PEG. Se observó correlación positiva y estadísticamente significativa entre el tamaño del RN y talla materna, peso al inicio de la gestación, peso al término de la gestación e IMC al inicio de la gestación.

Caracterización de 1.131 pacientes con cáncer cérvico-uterino según estadio FIGO: Hospital Guillermo Grant, 1999-2005 / Characterization of 1,131 patients with cervical carcinoma according FIGO classification: Hospital Guillermo Grant, 1999-2005

Objetivo: Analizar la distribución de mujeres con diagnóstico histológico de cáncer cérvico-uterino de acuerdo a la etapa clínica y edad. Método: Estudio de corte transversal de 1.131 mujeres clasificadas de acuerdo a la etapa FIGO en el Hospital Guillermo Grant (1999-2005). Resultados: 522 casos (46,1 por ciento) corresponden a Etapa 0, con edad promedio de 34,9 años; el 9 por ciento eran menores de 25 años; el 40,6 por ciento se concentró en el grupo entre 25 y 34 años. A cáncer invasor corresponden 609 mujeres (53,9 por ciento), con edad promedio de 51,2 años, en Etapa I el 36,6 por ciento, Etapa II el 31,8 por ciento, Etapa III el 26,1 por ciento y Etapa IV el 1,3 por ciento. Del grupo de mujeres con cáncer invasor, 117 (19,2 por ciento) eran mayores de 65 años y 4 (0,6 por ciento) menores de 25 años. Conclusión: La aplicación del Programa Nacional de pesquisa precoz del cáncer cérvico-uterino hizo que el 46,1 por ciento de los casos correspondan a diagnóstico precoz, contribuyendo a la tendencia nacional de disminución de la tasa de mortalidad por esta patología. Hay una disminución progresiva del número de casos de cáncer invasor a medida que se avanza en las etapas, coincidentemente hay un aumento en la edad de estas mujeres, es así que el 19,2 por ciento eran mayores de 65 años. De acuerdo con estos resultados es necesario analizar el costo-beneficio de incluir mujeres menores de 25 años y mayores de 65 en el programa de pesquisa precoz.

Objective: To analyze the distribution according to stage and age of women with histological cervical carcinoma confirmed diagnosis. Method: A cross sectional study of 1,131 women of the Hospital Guillermo Grant B with FIGO's classification, in the period 1999-2005. Results: From the 1,131 cases, 522 (46.1 percent) women correspond to Stage 0, the average age was 34.9 years; 9 percent were younger than 25 years of age; 40.6 percent were between 25-34 years old. Invasive cancer had 609 women (53.9 percent), average age was 51.2 years, corresponding 223 (36.6 percent) Stage I, 194 (31.8 percent) Stage II, 159 (26.1 percent) Stage III, and 8 (1.3 percent) Stage IV. The range of age in invasive stages was between 19-95 years. From the group of women with cancer, 117 (19.2 percent) were older than 65 years, and 4 women (0.6 percent) were younger than 25. Conclusion: The implementation of the National Program of early detection for cervical cancer caused that 46.1 percent of cases correspond to early diagnosis, contributing to the national trend of decreasing rate of mortality for this disease. There is a progressive decrease in the incidence of invasive cancer as it progresses in stages, coincidentally there is an increase in the age of these women, so that 19.2 percent were older than 65 years. Based on these results it is necessary to analyze the cost benefit of including women younger than 25 years and older than 65 in the screening.

Longitud cervical y fibronectina en el síntoma de parto prematuro / Cervical length and fetal fibronectin testing for the prediction of preterm labour

Antecedentes: En Chile el parto prematuro es la principal causa de morbilidad y mortalidad perinatal. Objetivo: Evaluar la utilidad clínica de la longitud cervical y la detección de fibronectina, en la predicción de parto prematuro. Método: Estudio observacional prospectivo, de corte transversal en 86 pacientes que consultaron por síntomas de parto prematuro (SPP), con membranas indemnes y edad gestacional entre las 22 y 34 semanas. El grupo estudio formado por gestantes con parto prematuro dentro de los 7 días. Al ingreso se tomó muestra cervical para fibronectina y se midió longitud cervical mediante ultrasonografía transvaginal. Resultados: De las 86 gestantes estudiadas, en 13 (15 por ciento) se produjo el parto dentro de los 7 días. La curva ROC mostró un área bajo la curva para longitud cervical de 0,475 y sensibilidad 31 por ciento (4/13), especificidad 96 por ciento (70/73), valor predictivo positivo 57 por ciento (4/7) y valor predictivo negativo 89 por ciento (70/79), riesgo relativo positivo 5,0 y riesgo relativo negativo 0,47 (p=0,014). El área bajo la curva para fibronectina fue 0,92 con una sensibilidad 77 por ciento (10/13), especificidad 90 por ciento (66/73), valor predictivo positivo (10/17) 59 por ciento y valor predictivo negativo 96 por ciento (66/69), riesgo relativo positivo 13,48 y riesgo relativo negativo 0,43 (p<0,001). Conclusión: En pacientes con síntoma de parto prematuro, cuello no remodelado y fibronectina cervical negativa, se asocian con bajo riesgo de parto prematuro. La fibronectina positiva, fue mejor predictor de parto prematuro dentro de los siete días y la longitud cervical fue superior para descartarlo.

Background: In Chile the preterm labor is the main cause of perinatal morbidity and mortality. Objective: To evaluate the clinical utility of the cervical length and fibronectin determination in predicting preterm delivery. Method: A prospective observational and transactional study was made, in 86 patients with preterm labor symptoms and gestational age between 22 and 34 weeks. The study group included patients with labor and delivery within a week of admission. From each patient a cervico-vaginal specimen was obtained to measure fibronectin and transvaginal ultrasonographic evaluation of the uterine cervix. Results: From 86 patients admitted to the study, thirteen had preterm labor (15 percent). The ROC curve showed an area under curve for cervical length of 0.475 and sensitivity 31 percent (4/13), specificity 96 percent (70/73), positive predictive value 57 percent(4/13), negative predictive value 88 percent (70/79), positive relative risk was 5.0, and the negative relative risk 0.47 (p=0.014); for fibronectin was 0.92 and sensitivity 77 percent (10/13), specificity 90 percent (66/73), positive predictive value 59 percent (10/17), negative predictive value 96 percent (66/69), positive relative riskof 13.48, negative relative risk 0.43 (p=0.014). Conclusion: In patients with premature labor symptoms, the cervical lengths none shortened and negative fibronectin result were associated with a low risk of having a preterm labor. Positive fibronectin was a better predictor of premature birth in a week of admission and the cervical length was the best in ruling out the occurrence of a premature birth.