RESUMEN
Propósito de la revisión: el objetivo de la revisión es delinear la fisiopatología de la Entero Colitis Necrotizante (ECN) clásica del recién nacido, proponer un listado de antecedentes perinatales que definan un grupo de riesgo y establecer parámetros simples y objetivos, que ayuden a establecer un diagnóstico clínico precoz. Recientes hallazgos: La mortalidad de la Entero Colitis Necrotizante clásica del recién nacido sigue siendo elevada. Aunque la enfermedad tiene varias presentaciones, es única con una única vía de instalación, la hipoperfusión intestinal como agente agresor inicial. Extracto: La falta de estrategias de prevención y el diagnóstico clínico muy tardío explican la mortalidad elevada de la ECN. Existe una gran confusión sobre el origen de la enferme-dad, dando a entender que existen diferentes tipos de ECN, aunque la enfermedad es única, tiene diferentes manifestaciones según las condiciones del recién nacido con una vía común de instalación, la hipoperfusión intestinal como agente agresor inicial. En este artículo se postula que reconocer a la hipoperfusión intestinal como agente agresor inicial, es "encontrar el hilo perdido", que permitirá desarrollar estrategias de prevención y tratamiento, al identificar los pacientes en riesgo de ECN y lograr el diagnóstico de manera precoz.
Purpose of the review: The objective of the review is to delineate the pathophysiology of the classic Entero Necrotizing Colitis (NEC) of the newborn, propose a list of perinatal ante-cedents that define a risk group and establish simple and objective parameters that help to establish an early clinical diagnosis. Recent findings: The mortality of the classic Necrotizing Entero Colitis of the newborn is still high. Although the disease has several presentations, it is unique with a single installation route, intestinal hypoperfusion as the initial offending agent. Excerpt: The lack of prevention strategies and very late clinical diagnosis explain the high mortality of NEC. There is great confusion about the origin of the disease, giving to under-stand that there are different types of NEC, although the disease is unique, it has different manifestations according to the conditions of the newborn with a common route of installation, intestinal hypoperfusion as an initial assailant agent. This article postulates that recog-nizing intestinal hypoperfusion as the initial offending agent is "finding the lost thread", that developing prevention and treatment strategies, by identifying patients at risk of NEC and achieving a diagnosis in a way early.
Objetivo da revisão: O objetivo da revisão é delinear a fisiopatologia da Entero Colite Necrosante (NEC) clássica do recém-nascido, propor uma lista de antecedentes perinatais que definem um grupo de risco e estabelecer parâmetros simples e objetivos que auxiliem no diagnóstico clínico precoce. Descobertas recentes: A mortalidade da Entero Colite Necrosante clássica do recém-nascido ainda é alta. Embora a doença tenha várias apresentações, é única com uma única via de instalação, a hipoperfusão intestinal como agente agressor inicial. Resumo: A falta de estratégias de prevenção e o diagnóstico clínico muito tardio explicam a alta mortalidade da NEC. Há grande confusão sobre a origem da doença, sugerindo que existem diferentes tipos de NEC, embora a doença seja única, ela tem diferentes manifestações dependendo das condições do recém-nascido com uma via comum de instalação, a hipoperfusão intestinal como agente. assaltante inicial. Este artigo postula que reconhecer a hipoperfusão intestinal como agente agressor inicial é "encontrar o fio condutor", o que permitirá o desenvolvimento de estratégias de prevenção e tratamento, por meio da identificação de pacientes em risco de NEC e do diagnóstico precoce.
Asunto(s)
Humanos , Recién Nacido , Enterocolitis Necrotizante , Reflejo de Inmersión , Hemorragia Gastrointestinal , Recién Nacido , Recien Nacido Prematuro , Endotoxemia , EnterocolitisRESUMEN
We sought to investigate the possibility that there are sex differences in the cardiovascular responses to trigeminal nerve stimulation (TGS) with cold exposure to the face at rest and during dynamic exercise. In 9 healthy men (age: 28 ± 3 yr; height: 178 ± 1 cm; weight: 77 ± 8 kg) and 13 women (age 26 ± 5 yr; height 164 ± 3 cm; weight 63 ± 7 kg) beat-to-beat heart rate (HR) and blood pressure were recorded. Mean arterial pressure (MAP), stroke volume (SV), cardiac index (CI), and total vascular resistance index (TVRI) were calculated. TGS was applied for 3 min at rest and in-between 10-min steady-state cycling exercise at a HR of 110 beats/min, the measurements were obtained during the last minute of each period. At rest, TGS increased MAP (men: Δ18 ± 8 mmHg; women: Δ23 ± 8 mmHg; means ± SD), TVRI (men: Δ1.1 ± 0.6 mmHg·l-1·min·m-2; women: Δ1.2 ± 1.2 mmHg·l-1·min·m-2) and SV (men: Δ19 ± 15 ml; women: Δ16 ± 11 ml) in both groups. CI increased with TGS in women but not in men. However, men presented a bradycardic response to TGS (Δ-11 ± 8 beats/min) that was not significant in women compared with baseline. Cycling exercise increased HR, MAP, SV, and CI and decreased TVRI in men and women. TGS during exercise further increased MAP in men and women and did not change CI in either group. SV and TVRI increased with TGS during exercise only in women. TGS during exercise evoked bradycardia in men (Δ-7 ± 9 beats/min), whereas HR was unchanged in women. Our findings indicate sex differences in TGS-related cardiovascular responses at rest and during exercise.
Asunto(s)
Reflejo de Inmersión , Estimulación Eléctrica/métodos , Ejercicio Físico/fisiología , Hemodinámica , Descanso/fisiología , Nervio Trigémino/fisiología , Adaptación Fisiológica , Adulto , Presión Arterial , Ciclismo , Frío , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Volumen Sistólico , Factores de Tiempo , Resistencia Vascular , Adulto JovenRESUMEN
The whale shark (Rhincodon typus) is a wide-ranging, filter-feeding species typically observed at or near the surface. This shark's sub-surface habits and behaviors have only begun to be revealed in recent years through the use of archival and satellite tagging technology. We attached pop-up satellite archival transmitting tags to 35 whale sharks in the southeastern Gulf of Mexico off the Yucatan Peninsula from 2003-2012 and three tags to whale sharks in the northeastern Gulf off Florida in 2010, to examine these sharks' long-term movement patterns and gain insight into the underlying factors influencing their vertical habitat selection. Archived data were received from 31 tags deployed on sharks of both sexes with total lengths of 5.5-9 m. Nine of these tags were physically recovered facilitating a detailed long-term view into the sharks' vertical movements. Whale sharks feeding inshore on fish eggs off the northeast Yucatan Peninsula demonstrated reverse diel vertical migration, with extended periods of surface swimming beginning at sunrise followed by an abrupt change in the mid-afternoon to regular vertical oscillations, a pattern that continued overnight. When in oceanic waters, sharks spent about 95% of their time within epipelagic depths (<200 m) but regularly undertook very deep ("extreme") dives (>500 m) that largely occurred during daytime or twilight hours (max. depth recorded 1,928 m), had V-shaped depth-time profiles, and comprised more rapid descents (0.68 m sec-1) than ascents (0.50 m sec-1). Nearly half of these extreme dives had descent profiles with brief but conspicuous changes in vertical direction at a mean depth of 475 m. We hypothesize these stutter steps represent foraging events within the deep scattering layer, however, the extreme dives may have additional functions. Overall, our results demonstrate complex and dynamic patterns of habitat utilization for R. typus that appear to be in response to changing biotic and abiotic conditions influencing the distribution and abundance of their prey.