Síndrome de Wilkie: caso clínico / Wilkie syndrome: case report

Resumen Introducción: El síndrome de Wilkie es una causa poco frecuente de obstrucción del tracto digestivo superior, se caracteriza por una disminución del ángulo aorto-mesentérico que resulta en compresión de la tercera porción del duodeno que produce síntomas obstructivos altos. Caso Clínico: Presentamos el caso de una mujer de 64 años, con historia de dolor abdominal, pirosis, saciedad precoz e intolerancia a la vía oral, en quien los estudios iniciales mostraron esofagitis, pero en quien los síntomas no mejoraron con el tratamiento clásico para enfermedad ácido péptica y en quien estudios imagenológicos adicionales sugerían el síndrome de Wilkie como causa de los síntomas. Discusión y Conclusión: Se trata de una patología que debe conocerse y considerar en paciente con historia de pérdida de peso, marcada intolerancia a la vía oral y falta de respuesta al manejo.

Introduction: Wilkie syndrome is a rare cause of upper gastrointestinal tract obstruction, it is characterized by a decrease in the aorto-mesenteric angle that results in a compression of the third portion of the duodenum causing high obstructive symptoms. Case Report: We present the case of a 64-year-old woman, with a history of abdominal pain, heartburn, early satiety, and intolerance to the oral route, in whom initial studies showed esophagitis, but in whom symptoms did not improve with the classic treatment for peptic acid disease, additional imaging studies suggested Wilkie syndrome. Discussion and Conclusión: It is a pathology that must be known and suspected in patients with a history of weight loss, marked intolerance to oral intake, and lack of treatment response.

Wildfires lead to decreased carbon and increased nitrogen concentrations in upland arctic streams.

The Central Siberian Plateau is undergoing rapid climate change that has resulted in increased frequency of forest fires and subsequent alteration of watershed carbon and nutrient dynamics. Across a watershed chronosequence (3 to >100 years since wildfire) we quantified the effects of fire on quantity and composition of dissolved organic matter (DOM), stream water nutrient concentrations, as well as in-stream nutrient uptake. Wildfires increased concentrations of nitrate for a decade, while decreasing concentrations of dissolved organic carbon and nitrogen (DOC and DON) and aliphatic DOM contribution for five decades. These post-wildfire changes in stream DOM result in lower uptake efficiency of in-stream nitrate in recently burned watersheds. Nitrate uptake (as uptake velocity) is strongly dependent on DOM composition (e.g. polyphenolics), ambient dissolved inorganic nitrogen (DIN), and DOC to DIN ratios. Our observations and experiments suggest that a decade-long pulse of inorganic nitrogen and a reduction of DOC export occur following wildfires in streams draining the Central Siberian Plateau. Increased fire frequency in the region is thus likely to both decrease DOM and increase nitrate delivery to the main stem Yenisei River, and ultimately the Arctic Ocean, in the coming decades.

Lithium increases melanin-concentrating hormone mRNA stability and inhibits tyrosine hydroxylase gene expression in PC12 cells.

Melanin-concentrating hormone (MCH) is a cyclic peptide involved in the regulation of food-intake behaviour and stress response in mammals. Expression of the MCH gene predominates in hypothalamic neurons. Mechanisms governing the regulation of expression of MCH gene in established cell lines were not explored yet. Here, we analysed the actions of nerve growth factor (NGF), dexamethasone, forskolin and lithium on MCH mRNA levels in the PC12 pheochromocytoma cell line. We compared them with those observed on tyrosine hydroxylase (TH) mRNA, constitutively expressed in PC12 cells, and neurotensin (NT) mRNA, taken as a control. In untreated cells, MCH RNA species of high molecular weight were found. Exposure of cells at a combination of NGF and lithium resulted in decreased expression of these MCH RNAs and in the transient production of mature MCH mRNA. Strikingly, after short exposure of PC12 cells to NGF, lithium per se elicited a marked increase in MCH mRNA levels whilst it exerted a potent inhibitory action on TH mRNA expression. Detailed investigations revealed that lithium enhanced MCH mRNA expression through post-transcriptional mechanisms whereas it regulated TH gene expression mainly at the level of transcription. These results demonstrate that lithium, an agent widely used for treatment of manic depressive illness, can exert an opposite effect on MCH and TH mRNA production in PC12 cells. The MCH gene system in NGF-treated PC12 cells provides a good opportunity for studying the effect of lithium on gene expression at post-transcriptional levels in a neuron-like cellular model.