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RESUMEN Demostrar mediante la disección de piezas anatómicas y de imágenes ultrasonográficas prenatales del corazón fetal la presencia del fulcro cardíaco como estructura de fijación que sirve de soporte a la banda miocárdica helicoidal. Se disecaron 6 corazones de fetos entre las 20 y 24 semanas de edad gestacional productos de abortos espontáneos, logrando encontrar el fulcro cardíaco en la proximidad de la aorta y conexiones con fibras miocárdicas. En 50 embarazos simples con fetos entre las 18 y 37 semanas de gestación, mediante ultrasonografía cardíaca fetal se obtuvieron las modalidades 2D, Doppler, color y tridimensión, STIC, HD Flow y speckle tracking, imágenes, medidas del fulcro y su cinética. Con la estrategia descrita se identificó y demostró la presencia del fulcro cardíaco o palanca miocárdica, estableciendo sus características anatómicas, conexiones con fibras miocárdicas del asa cardíaca y la biometría según la edad gestacional. Se formula una hipótesis sobre la biomecánica o cinética del fulcro durante el ciclo cardíaco. Para que el corazón cumpla su función de bomba aspirante e impelente debe poseer un punto de apoyo, una palanca o fulcro, que constituye una especie de unidad músculo-tendinosa. Dicha palanca presenta desplazamientos mixtos durante la torsión y detorsión del miocardio. Sus diámetros aumentan progresivamente a medida que avanza la gestación.

ABSTRACT To demonstrate by dissection of anatomical specimens and prenatal ultrasonographic images of the fetal heart the presence of the cardiac fulcrum as a fixation structure supporting the helical myocardial band. Six hearts of fetuses between 20-24 weeks of gestational age resulting from spontaneous abortions were dissected, finding the cardiac fulcrum in the proximity of the aorta and connections with myocardial fibers. In 50 singleton pregnancies with fetuses between 18-37 weeks of gestation, fetal cardiac ultrasonography was used to obtain 2D, Doppler, color and three-dimensional modalities, STIC, HD Flow and speckle tracking, images, fulcrum measurements and its kinetics. With the described strategy, the presence of the cardiac fulcrum or myocardial lever was identified and demonstrated, establishing its anatomical characteristics, connections with myocardial fibers of the cardiac loop and the biometry according to gestational age. A hypothesis on the biomechanics or kinetics of the fulcrum during the cardiac cycle is formulated. In order for the heart to fulfill its function as an aspirating and impelling pump, it must have a support point, a lever or fulcrum, which constitutes a sort of muscle-tendon unit. This lever presents mixed displacements during myocardial torsion and detorsion. Its diameters increase progressively as gestation advances.

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Objetivo. Proponer un índice de rendimiento biventricular basado en los valores promedio de la duración del ciclo cardíaco de cada uno de los ventrículos, determinar la variable incluida en el estudio con la correlación estadística más significativa, establecer valores de referencia que permitan identificar el trabajo de cada ventrículo en función de dicha variable y obtener un índice de gasto biventricular equilibrado. Metodología. Estudio prospectivo y transversal en fetos de 168 gestantes, en embarazos entre las 16 y 38 semanas sin patologías materno-fetales. Se obtuvieron ondas de velocidad de flujo de ambas válvulas atrioventriculares y el tiempo total del ciclo sístole-diástole se calculó en milisegundos para cada válvula. Se calcularon promedios, desviación estándar y puntuación Z del tiempo sistólico-diastólico para cada ventrículo y el índice de rendimiento ventricular individual dividiendo el valor obtenido entre la frecuencia cardiaca fetal. Se obtuvo el valor promedio de ambos y este, al ser dividido por la frecuencia cardíaca, permitió obtener el índice de rendimiento biventricular para establecer la correlación entre este, la frecuencia cardiaca fetal y la edad de gestación. Resultados. Se halló valores de tiempo sistólico-diastólico en milisegundos para el ventrículo derecho de 420,8 (DE ±28,3) y para el ventrículo izquierdo de 418,8 (DE ±26,3), sin diferencias estadísticamente significativas (p=0,371). La correlación con la frecuencia cardíaca fetal resultó negativa para ambos ventrículos (-0,491 y -0,553; p<0,05). El tiempo promedio biventricular fue de 418,37 ms (± 20,59) y la correlación con la edad gestacional de 0,48 (p<0,05); la correlación con la frecuencia cardiaca fetal fue negativa, -0,50 (p<0,05). El índice de rendimiento biventricular mostró valores de 2,8 (extremos 2,4 (P5) y 3,4 (P95)). La correlación entre el índice de rendimiento biventricular y la frecuencia cardiaca fetal fue 0,78 (p<0,05), de menor grado (0,27) con la edad gestacional. Conclusiones. Se demostró que los tiempos sistólico-diastólicos de cada ventrículo no difirieron entre sí y se correlacionaron de manera negativa con la frecuencia cardiaca fetal. Se comprobó que es posible evaluar el ciclo cardíaco fetal de cada ventrículo mediante el índice de rendimiento ventricular, así como calificar con el índice de rendimiento biventricular el gasto cardíaco combinado como equilibrado.

Objectives: To propose a biventricular performance index based on the average values of the duration of the cardiac cycle of each of the ventricles, to determine the variable included in the study with the most significant statistical correlation, to establish reference values that allow the work of each ventricle to be identified according to this variable, and to obtain a balanced biventricular output index. Methodology: Prospective and cross-sectional study in fetuses of 168 pregnant women, in pregnancies between 16 and 38 weeks without maternal-fetal pathologies. Flow velocity waves were obtained from both atrioventricular valves and the total systole-diastole cycle time was calculated in milliseconds for each valve. Averages, standard deviation, and Z-score were calculated of the systolic-diastolic time for each ventricle and the individual ventricular performance index (VPI) were calculated by dividing the value obtained by the fetal heart rate (FHR). The average value of both was obtained and this, when divided by the heart rate, made it possible to obtain the biventricular performance index (BPI) to establish the correlation between this, the fetal heart rate and gestational age. Results: Systolic-diastolic time values in milliseconds for the right ventricle were 420.8 (SD ±28.3) and for the left ventricle 418.8 (SD ±26.3), with no statistically significant differences (p<0.371). The correlation with the FHR was negative for both ventricles: (-0.491 and -0.553; p<0.05). The mean biventricular time was 418.37 ms (±20.59) and the correlation with gestational age was 0.48 (p<0.05); the correlation with FHR was negative, -0.50 (p<0.05).The BPI showed values of 2.8 (extremes 2.4 (P5) and 3.4 (P95)). The correlation between BPI and FHR was 0.78 (p<0.05) and of lesser degree with gestational age (0.27; p<0.05). Conclusions: It was demonstrated that the systolic-diastolic times of each ventricle did not differ from each other and were negatively correlated with fetal heart rate. It was shown that it is possible to evaluate the fetal cardiac cycle of each ventricle by means of the ventricular performance index as well as to qualify with the biventricular performance index the combined cardiac output as balanced.

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RESUMEN Antecedentes. Lograr un método ideal que evalúe el potencial de crecimiento fetal es una aspiración incumplida en nuestra disciplina, e impone la necesidad de una evaluación individualizada, a través de nuevas herramientas y multiparámetros integrados. Objetivos. Evaluar la correlación y establecer valores de referencia del índice cefálico/abdominal/femoral (CAF) con la edad gestacional (EG) y el peso fetal estimado, para tipificar la evolución del crecimiento fetal como adecuado o no para la edad gestacional, y correlacionar con el peso del recién nacido a término. Pacientes y métodos. Se estudiaron 1 032 embarazos con embarazo simple y sin complicaciones, de 12 a 38 semanas de gestación, en el Centro Policlínico de Valencia, Venezuela, entre los años 2015 y 2017. Las medidas ecográficas y el peso fetal se estimaron a intervalos de 3 a 5 semanas. Los parámetros estudiados fueron circunferencia cefálica (CC), circunferencia abdominal (CA) y longitud del fémur (FL), integrados en la fórmula índice CAF = [(CC + CA) -FL]. Se aplicó el modelo de regresión cúbica y puntaje Z en 256 casos seguidos hasta el parto. Se establecieron tres grupos de CAF: a) CAF <50, b) CAF 50 a 57, y c) CAF ≥58, calculando la media ± desviación estándar de los pesos de los recién nacidos en cada grupo. Resultados. Según las semanas de gestación, el índice CAF reveló un R² = 0,96, p <0,05, mientras que para el peso fue R² = 0,92, p <0,05. En 256 casos seguidos hasta el parto, cuando el CAF tenía valor igual o superior a 58, el peso del recién nacido fue 3 361 ± 484 g, con diferencias estadísticamente significativas en relación al resto de grupos (prueba de student p <0,05). Conclusiones. El índice CAF es un método multiparméetrico que permite, a través de evaluaciones seriadas, determinar el potencial de crecimiento individual esperado y virtualmente también identificar sus desviaciones.

ABSTRACT Background: Achieving an ideal method to assess the potential for fetal growth is an unfulfilled aspiration in our discipline, and imposes the need for individualized evaluation using new tools and integrated multi-parameters. Objectives: To evaluate correlation and to establish cephalic/abdominal/femoral (CAF) index reference values with gestational age (GA) and estimated fetal weight, in order to classify fetal growth evolution as adequate or not adequate for gestational age, and correlation with weight of the newborn at term. Patients and methods: 1 032 simple and not complicated pregnancies 12 to 38 weeks of gestation were studied at the Polyclinic Center of Valencia, Venezuela, between 2015-2017. Ultrasound measurements and fetal weight were estimated at 3-5 weeks intervals. Studied parameters were head circumference (HC), abdominal circumference (AC) and femur length (FL), integrated in the CAF index = [(HC + AC) - FL] formula. The cubic regression model and Z-score were applied in 256 cases followed up to delivery. Three CAF groups were established: a) CAF <50, b) CAF 50-57, and c) CAF ≥58; the mean ± SD newborn weights were calculated in each group. Results: The CAF index revealed an R² = 0.96, p <0.05 for weeks of gestation, and R² = 0.92, p <0.05 for weight. In 256 cases followed up to delivery, when the CAF index was equal or greater than 58, the newborn weight was 3 361 ± 484 g, with statistically significant differences as compared to the other groups (student test p <0.05). Conclusions: The CAF index is a multiparametric method that allows to determine by serial evaluations the expected individual growth potential and virtually to identify deviations.

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INTRODUCTION: In intrauterine growth restriction (IUGR), increased uteroplacental vascular impedance contributes to preferential flow to left ventricle (LV), with consequent alteration of its compliance and increased left atrial (LA) pressure. Pulmonary vein pulsatility index (PVPI) reflects the increased impedance to LA filling and could be used as a cardiac monitoring parameter in IUGR. MATERIAL AND METHODS: A total of 27 IUGR fetuses (group 1), 28 fetuses with appropriate growth for gestational age from hypertensive mothers (group 2), and 28 controls (group 3) were studied. Pulsatility indices (PIs) of pulmonary veins and ductus venosus were calculated by Doppler echocardiography. Obstetric ultrasound was used to assess the PIs of uterine, umbilical, and middle cerebral arteries. Statistical analysis used analysis of variance, post-hoc Tukey, and Pearson's tests. RESULTS: Mean PVPI was higher in IUGR group (1.27 ± 0.39) when compared to groups 2 (1.02 ± 0.37; p = 0.01) and 3 (0.75 ± 0.12; p < 0.001). In group 2, moderate correlation between PVPI and ductus venosus pulsatility index (DVPI) was found but not between PVPI and cerebroplacental ratio (CPR). DISCUSSION: Higher PVPI in IUGR reflects decreased LV compliance and altered LA dynamics. As LV dysfunction precedes right ventricle, our results suggest that PVPI could be an early echocardiographic parameter of fetal diastolic function in IUGR.

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Background The Doppler effect has allowed the characterization of several vessels in maternal-fetal circulation that have been used for practical purposes. Our review of the literature showed a paucity of information about fetal pulmonary artery pressure (FMPAP) and its behavior in regard to gestational age (GA). The objectives of the study were to evaluate a formula to calculate the main FMPAP and its correlation with GA. Methods A total of 337 fetuses without obvious pathology were studied prospectively using Doppler evaluation of the FMPAP. Using the fetal main pulmonary artery Doppler acceleration time (FMPAT), we obtained the FMPAP using the following formula: FMPAP=90 - (0.62×FMPAT). Regression analyses, Pearson's bivariate correlation and paired sample t-test were used when appropriate. Results FMPAT increases while FMPAP decreases with GA. Pearson's correlation coefficient for FMPAP and GA was -0.544 (P-value<0.001) and for FMPAT and GA was 0.556 (P-value<0.001). FMPAP and FMPAT were highly correlated (R=-0.972; P<0.001). Conclusion Pulmonary artery pressure in the fetus decreases with GA.

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BACKGROUND: Splenic abscesses are rare entities; reports are commonly described in immunocompromised patients (72%) as: hematologic diseases, diabetes, endocarditis, acquired immunodeficiency syndrome, transplant patients and subjects who had abdominal trauma or splenic infarction. The main and most serious complication is the abscess rupture into the peritoneal cavity or adjacent organs (stomach or colon), which determines hemodynamic instability or septic state. CLINICAL CASE: Fifty-year-old man, who was admitted at Emergency Room due eight days' progressive, oppressive, and current pain; intensity 4/10, irradiated at hemi-back, which was higher intensity during the standing and decreased at supine position. It was accompanied by nausea and vomiting in two occasions. LABORATORY RESULTS: Hemoglobin 15.1g/dl, hematocrit 45.2%, platelets 176×103, 23.1×103 leukocytosis, neutrophils 92%. Simple abdominal radiographic studies revealed in 'ground glass' and radiopaque imagines. CONCLUSIONS: At presence of free air inside the abdominal cavity, is usually to think of a complicated diverticular disease, intestinal perforation or perforated peptic ulcer. The actual medical literature described very few cases of splenic abscess with pneumoperitoneum as cardinal manifestation. In our case, the splenic abscess was detected during exploratory laparotomy and only in retrospective the imaging studies were interpreted.

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This research was designed to analyze the possible associations of Arg389Gly ADRB1 and Trp64Arg ADRB3 polymorphisms in children with obesity. A cross-sectional study included 1,046 school-age Mexican participants (6-12 years old) from the cities of San Luis PotosÍ and León. Children were classified as non-obese or obese according to their body mass index (BMI) percentile; obese children had a BMI≥95th percentile for sex and age. Biochemical data were collected. Polymorphisms were detected using TaqMan qPCR assay. A logistic regression analysis was used to calculate the risk of obesity based on genotypes. Differences were found between groups where obese children had a significant increase in systolic and diastolic blood pressure, fasting plasma glucose, insulin, HOMA-IR, LDL-cholesterol, triglycerides, and lower HDL-cholesterol compared with the normal weight group (P<0.05). The distribution of allele frequency in the population was Arg= 87.4 and Gly= 12.6 (Hardy Weinberg equilibrium c2 = 3.16 , P = 0.07 ); Trp= 81.5 and Arg= 18.5 (Hardy Weinberg equilibrium c2 = 2.2, P = 0.14 ) for ADRB1 and ADRB3, respectively. Even though no different frequencies of Arg389Gly polymorphism between groups were found (P = 0.08), children carriers of one Gly389 ADRB1 allele had a risk for obesity of OR=1.40 (95%CI, 1.03-1.90, P = 0.03) after adjustment for age and gender. No other association was found for Trp64Arg ADRB3 polymorphism. Only the Arg389Gly ADRB1 polymorphism was associated with risk for obesity in Mexican children.

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MOTIVATION: Rapid advances in genotyping and genome-wide association studies have enabled the discovery of many new genotype-phenotype associations at the resolution of individual markers. However, these associations explain only a small proportion of theoretically estimated heritability of most diseases. In this work, we propose an integrative mixture model called JBASE: joint Bayesian analysis of subphenotypes and epistasis. JBASE explores two major reasons of missing heritability: interactions between genetic variants, a phenomenon known as epistasis and phenotypic heterogeneity, addressed via subphenotyping. RESULTS: Our extensive simulations in a wide range of scenarios repeatedly demonstrate that JBASE can identify true underlying subphenotypes, including their associated variants and their interactions, with high precision. In the presence of phenotypic heterogeneity, JBASE has higher Power and lower Type 1 Error than five state-of-the-art approaches. We applied our method to a sample of individuals from Mexico with Type 2 diabetes and discovered two novel epistatic modules, including two loci each, that define two subphenotypes characterized by differences in body mass index and waist-to-hip ratio. We successfully replicated these subphenotypes and epistatic modules in an independent dataset from Mexico genotyped with a different platform. AVAILABILITY AND IMPLEMENTATION: JBASE is implemented in C++, supported on Linux and is available at http://www.cs.toronto.edu/∼goldenberg/JBASE/jbase.tar.gz. The genotype data underlying this study are available upon approval by the ethics review board of the Medical Centre Siglo XXI. Please contact Dr Miguel Cruz at mcruzl@yahoo.com for assistance with the application. CONTACT: anna.goldenberg@utoronto.ca SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

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BACKGROUND: We explored the imputation performance of the program IMPUTE in an admixed sample from Mexico City. The following issues were evaluated: (a) the impact of different reference panels (HapMap vs. 1000 Genomes) on imputation; (b) potential differences in imputation performance between single-step vs. two-step (phasing and imputation) approaches; (c) the effect of different INFO score thresholds on imputation performance and (d) imputation performance in common vs. rare markers. METHODS: The sample from Mexico City comprised 1,310 individuals genotyped with the Affymetrix 5.0 array. We randomly masked 5% of the markers directly genotyped on chromosome 12 (n=1,046) and compared the imputed genotypes with the microarray genotype calls. Imputation was carried out with the program IMPUTE. The concordance rates between the imputed and observed genotypes were used as a measure of imputation accuracy and the proportion of non-missing genotypes as a measure of imputation efficacy. RESULTS: The single-step imputation approach produced slightly higher concordance rates than the two-step strategy (99.1% vs. 98.4% when using the HapMap phase II combined panel), but at the expense of a lower proportion of non-missing genotypes (85.5% vs. 90.1%). The 1,000 Genomes reference sample produced similar concordance rates to the HapMap phase II panel (98.4% for both datasets, using the two-step strategy). However, the 1000 Genomes reference sample increased substantially the proportion of non-missing genotypes (94.7% vs. 90.1%). Rare variants (<1%) had lower imputation accuracy and efficacy than common markers. CONCLUSIONS: The program IMPUTE had an excellent imputation performance for common alleles in an admixed sample from Mexico City, which has primarily Native American (62%) and European (33%) contributions. Genotype concordances were higher than 98.4% using all the imputation strategies, in spite of the fact that no Native American samples are present in the HapMap and 1000 Genomes reference panels. The best balance of imputation accuracy and efficiency was obtained with the 1,000 Genomes panel. Rare variants were not captured effectively by any of the available panels, emphasizing the need to be cautious in the interpretation of association results for imputed rare variants.

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El objetivo de este trabajo es estudiar la circulación umbílico-porto-ductal en fetos con edades comprendidas entre las 20 y 25 semanas de gestación. Se hizo un estudio prospectivo de 50 fetos provenientes de abortos espontáneos y sin malformaciones, los cuales previa fijación fueron disecados mediante secciones con bisturí y ablación mecánica e hídrica del tejido hepático exponiendo la circulación umbilical hasta la aurícula derecha en la Unidad de Perinatología de la Universidad de Carabobo y Centro de Entrenamiento en Ultrasonografía Perinatal de la Maternidad Privada Las Acasias, Valencia, Estado Carabobo. El sistema venoso umbílico-portal conduce la sangre desde la placenta, vía vena umbilical que se contínua con el seno portal, de este nacen las venas porta derecha e izquierdas intrahepáticas y el ductus venoso, la vena porta principal que es extrahepática, drena a la porta intrahepática derecha, la sangre del sistema porta drena en las venas suprahepáticas y estas junto al ductus venoso y la vena cava inferior confluyen en el vestíbulo venoso sugdiafragmático. La anatomía y la fisiología del sistema venoso umbílico-porto-ductal es de gran importancia para la evaluación de las condiciones hemodinámicas fetales. Para su abordaje es necesario un profundo conocimiento de su arquitectura habitual y resulta necesario el uso de una nomenclatura estándar

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