Loss of glutamatergic signalling from MCH neurons reduced anxiety-like behaviours in novel environments.

Melanin-concentrating hormone (MCH) neurons within the hypothalamus are heterogeneous and can coexpress additional neuropeptides and transmitters. The majority of MCH neurons express vesicular transporters to package glutamate for synaptic release, and MCH neurons can directly innervate downstream neurons via glutamate release. Although glutamatergic signalling from MCH neurons may support physiological and behavioural roles that are independent of MCH (e.g., in glucose homeostasis and nutrient-sensing), it can also mediate similar roles to MCH in the regulation of energy balance. In addition to energy balance, the MCH system has also been implicated in mood disorders, as MCH receptor antagonists have anxiolytic and anti-depressive effects. However, the contribution of glutamatergic signalling from MCH neurons to mood-related functions have not been investigated. We crossed Mch-cre mice with floxed-Vglut2 mice to delete the expression of the vesicular glutamate transporter 2 (Vglut2) and disable glutamatergic signalling specifically from MCH neurons. The resulting Mch-Vglut2-KO mice showed Vglut2 deletion from over 75% of MCH neurons, and although we did not observe changes in depressive-like behaviours, we found that Mch-Vglut2-KO mice displayed anxiety-like behaviours. Mch-Vglut2-KO mice showed reduced exploratory activity when placed in a new cage and were quicker to consume food placed in the centre of a novel open arena. These findings showed that Vglut2 deletion from MCH neurons resulted in anxiolytic actions and suggested that the anxiogenic effects of glutamate are similar to those of the MCH peptide. Taken together, these findings suggest that glutamate and MCH may synergize to regulate and promote anxiety-like behaviour.

Female mice exposed to low doses of dioxin during pregnancy and lactation have increased susceptibility to diet-induced obesity and diabetes.

OBJECTIVE: Exposure to persistent organic pollutants is consistently associated with increased diabetes risk in humans. We investigated the short- and long-term impact of transient low-dose dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin, TCDD) exposure during pregnancy and lactation on glucose homeostasis and beta cell function in female mice, including their response to a metabolic stressor later in life. METHODS: Female mice were injected with either corn oil (CO; vehicle control) or 20 ng/kg/d TCDD 2x/week throughout mating, pregnancy and lactation, and then tracked for 6-10 weeks after chemical exposure stopped. A subset of CO- and TCDD-exposed dams was then transferred to a 45% high-fat diet (HFD) or remained on a standard chow diet for an additional 11 weeks to assess the long-term effects of TCDD on adaptability to a metabolic stressor. To summarize, female mice were transiently exposed to TCDD and then subsequently tracked beyond when TCDD had been excreted to identify lasting metabolic effects of TCDD exposure. RESULTS: TCDD-exposed dams were hypoglycemic at birth but otherwise had normal glucose homeostasis during and post-TCDD exposure. However, TCDD-exposed dams on a chow diet were modestly heavier than controls starting 5 weeks after the last TCDD injection, and their weight gain accelerated after transitioning to a HFD. TCDD-exposed dams also had an accelerated onset of hyperglycemia, impaired glucose-induced plasma insulin levels, reduced islet size, increased MAFA-ve beta cells, and increased proinsulin accumulation following HFD feeding compared to controls. Overall, our study demonstrates that low-dose TCDD exposure during pregnancy has minimal effects on metabolism during the period of active exposure, but has detrimental long-term effects on metabolic adaptability to HFD feeding. CONCLUSIONS: Our study suggests that transient low-dose TCDD exposure in female mice impairs metabolic adaptability to HFD feeding, demonstrating that dioxin exposure may be a contributing factor to obesity and diabetes pathogenesis in females.

Normal Intracranial Translucency Values During the First Trimester of Gestation in a Latin American Population.

OBJECTIVES: The purpose of this study was to establish intracranial translucency reference values in healthy fetuses from a Latin American population. METHODS: This work was a cross-sectional retrospective correlational study. A review of sonographic reports from women between gestational ages of 11 weeks and 13 weeks 6 days at 2 health institutes in Bogota, Colombia, whose fetuses had a crown-rump length of 45 to 84 mm was conducted between January 1, 2010, and December 31, 2012. Women with multiple fetuses or with a deceased fetus were excluded. RESULTS: Data corresponding to 1520 obstetric sonographic examinations were included in the statistical analysis. The crown-rump length was between 45 and 84 mm, with a median of 65 mm (interquartile range, 58-73 mm). The median intracranial translucency was 1.7 mm (interquartile range, 1.4-2.2 mm). Different percentiles (1st, 5th, 10th, 25th, 50th, 75th, 90th, 95th, and 99th) were established for each crown-rump length value. A correlation between crown-rump length and intracranial translucency was found, which seemed to be linear. The intracranial translucency value was not significantly correlated with the frontomaxillary angle but was correlated with nuchal translucency, nasal bone length, and metopic suture length. CONCLUSIONS: We present normal intracranial translucency values in the first trimester of single gestations with live fetuses in a Latin American population. These values are similar to those described in other populations. The intracranial translucency value was linearly correlated with crown-rump length in fetuses between gestational ages of 11 weeks and 13 weeks 6 days, which is consistent with previous publications, although these data cannot be interpreted independently.

Diagnóstico prenatal de la colelitiasis fetal: reporte de casos y revisión de la literatura / Prenatal diagnosis of fetal cholelithiasis: three case reports and literature review

Objetivo: realizar el reporte de una serie de casos evaluados a través de ecografía convencional y Examen Tridimensional Extendido (3DXI), y realizar una revisión de la literatura respecto a las imágenes más frecuentes de la ecografía de 2 y 3D, y métodos diagnósticos complementarios. Materiales y métodos: se presenta el reporte de tres casos evaluados en la Unidad de Medicina Materno-Fetal de la Clínica Colsubsidio Orquídeas, centro de referencia de nivel III que atiende población embarazada de alto riesgo obstétrico perteneciente al régimen contributivo. Ninguno de los casos se asoció con hallazgo de malformaciones y su evolución fue favorable. Se realizó una revisión de la literatura con base en las palabras clave: colelitiasis fetal, vesícula biliar fetal, barro biliar fetal y diagnóstico prenatal, en las bases de datos Pubmed, Ebsco, Ovid, Proquest desde el año 1980 al 2011. Se incluyeron artículos de revisión, reporte de casos, estudios de validez diagnóstica o estudios de corte transversal publicados durante el mismo periodo. Resultados: se encontraron 41 artículos de los cuales se incluyeron 25 correspondientes a: series de casos (9), revisiones (9), estudios de exactitud diagnóstica (7). El diagnóstico de colelitiasis se hace durante el final del segundo o inicio del tercer trimestre de gestación en el examen de vigilancia y crecimiento fetal, y requiere que sea corroborado posnatalmente. No se han documentado complicaciones asociadas a este diagnóstico en vida posnatal. Generalmente tiene buena evolución prenatal y posnatal, sin secuelas en el futuro y con resolución espontánea. Solo un estudio refiere la resonancia nuclear magnética como una opción posnatal. Los métodos tipo resonancia magnética dinámica (DMR) y 3DXI no fueron referidos en la literatura. Conclusión: la colelitiasis fetal es un hallazgo incidental aunque el diagnóstico generalmente se realiza con ecografía 2D; el examen tridimensional extendido podría ser una nueva herramienta diagnóstica para tener en cuenta como alternativa complementaria en el diagnóstico prenatal.

Objective: Reporting a series of cases which were evaluated by conventional echography and 3D eXtended imaging (3DXI) and reviewing the pertinent literature regarding the most frequent 2D and 3D ultrasound images and complementary diagnostic methods. Materials and methods: Three cases are reported which were evaluated in the Maternal-Fetal Medicine Unit at the Clínica Colsubsidio Orquídeas (a reference centre) which attends a high obstetric risk pregnant population from the contributory health insurance system. None of the cases were associated with findings of malformations and they all had favorable evolution. A literature review was made of Pubmed, Ebsco, Ovid and Proquest data-bases from 1980 to 2011 based on the following key words: fetal cholelithiasis, fetal biliary gallbladder, fetal biliary mud, prenatal diagnosis; review articles, case reports, diagnostic validity/accuracy studies or cross-sectional studies published during the same period were included. Results: 25 of the 41 articles found were included: 9 case series, 9 reviews and 7 diagnostic accuracy studies. Cholelithiasis was usually diagnosed during the end of the second or third trimester of pregnancy during fetal growth and welfare ultrasound exam. Diagnosis must be postnatally corroborated. Complications associated with a diagnosis of cholelithiasis during postnatal life have not been documented. Cases usually have good prenatal and postnatal evolution without future sequelae and usually have spontaneous resolution. Only one study referred to nuclear magnetic resonance as being a postnatal option. DMR and 3DXI-type methods were not referred to in the literature. Conclusion: Fetal cholelithiasis is an incidental finding; even though diagnosis is usually made by 2D echography, 3D eXtended imaging could provide a new diagnostic tool as a complementary alternative in prenatal diagnosis.

Muerte fetal anteparto: ¿es una condición prevenible? / Fetal death syndrome: could it be prevented?

El síndrome de muerte fetal se define como la muerte del feto que se presenta después de la semana 20 de gestación, en ausencia de trabajo de parto instaurado. Constituye un tercio de toda la mortalidad fetal e infantil y más de 50% de todas las muertes perinatales en los países desarrollados. Las causas de muerte fetal raramente se reportan y la mayoría se desconoce. Se pretende con este artículo hacer una revisión que permita entender la fisiopatología de la entidad, evaluar los factores de riesgo y tratar de brindar a nuestras pacientes la posibilidad de un embarazo exitoso. Se realizó una revisión de la literatura existente de acuerdo con las bases de datos PubMed, EBSCO, Ovid y Proquest, desde el año 2000 hasta 2008. A pesar de la disminución significativa de los óbitos fetales en las últimas décadas, sigue siendo un serio problema de salud pública, no sólo por ser una condición prevalente, sino por el subregistro y la ausencia de reportes confiables.

Fetal death syndrome is one third of all fetal and infant mortality by over 50% of all perinatal deaths in developed countries. The causes of fetal death are rarely reported and most of them are unknown. This article intends to review and to understand the pathophysiology of the entity, to assess risk factors and to try to give our patients the possibility of a successful pregnancy. A review the literature was made according to the PubMed database, EBSCO, Proquest and Ovid from 2000 to 2008. Despite the significant decrease in fetal deaths in the last decades, fetal death syndrome remains a serious public health problem not only because it is a prevalent condition, but by underreporting and the lack of reliable reporting.