Black esophagus or AEN syndrome is an important cause of upper gastrointestinal hemorrhage with striking endoscopic presentation in a clinically compromised individual with multiple co-morbidities. Structured conservative management with correction of underlying etiology and acid suppression is essential to improved prognosis. Associated duodenal pathology on endoscopy is a reflection of the degree of initial insult and a clinical predictor for potential stricture development. Proximal extension of the black esophagus may be related to the degree of hyperglycemia. Increased awareness of AEN syndrome will lead to early recognition and proper treatment.

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Patel HM, Mast JL, Sinoway LI, Muller MD. Effect of healthy aging on renal vascular responses to local cooling and apnea. J Appl Physiol 115: 90 -96, 2013. First published May 2, 2013 doi:10.1152/japplphysiol.00089.2013.-Sympathetically mediated renal vasoconstriction may contribute to the pathogenesis of hypertension in older adults, but empirical data in support of this concept are lacking. In 10 young (26 Ϯ 1 yr) and 11 older (67 Ϯ 2 yr) subjects, we quantified acute hemodynamic responses to three sympathoexcitatory stimuli: local cooling of the forehead, cold pressor test (CPT), and voluntary apnea. We hypothesized that all stimuli would increase mean arterial blood pressure (MAP) and renal vascular resistance index (RVRI) and that aging would augment these effects. Beat-bybeat MAP, heart rate (HR), and renal blood flow velocity (from Doppler) were measured in the supine posture, and changes from baseline were compared between groups. In response to 1°C forehead cooling, aging was associated with an augmented MAP (20 Ϯ 3 vs. 6 Ϯ 2 mmHg) and RVRI (35 Ϯ 6 vs. 16 Ϯ 9%) but not HR. In older adults, there was a positive correlation between the cold-induced pressor response and forehead pain (R ϭ 0.726), but this effect was not observed in young subjects. The CPT raised RVRI in both young (56 Ϯ 13%) and older (45 Ϯ 8%) subjects, but this was not different between groups. Relative to baseline, end-expiratory apnea increased RVRI to a similar extent in both young (46 Ϯ 14%) and older (41 Ϯ 9%) subjects. During sympathetic activation, renal vasoconstriction occurred in both groups. Forehead cooling caused an augmented pressor response in older adults that was related to pain perception. cold face test; renal blood flow; vasoconstriction; peripheral chemoreflex; noxious cooling THE KIDNEY IS A VITAL ORGAN for salt and water homeostasis and receives ϳ20% of cardiac output in resting humans (60). Furthermore, the renal vasculature is innervated by sympathetic nerves that allow for alpha adrenergic-mediated vasoconstriction during times of stress (i.e., exercise and orthostasis) (6, 43). As such, acute adjustments in renal blood flow importantly contribute to whole-body fluid balance and blood pressure control. It follows that chronic impairments in this process (e.g., enhanced water reabsorption and/or enhanced vasoconstriction) predispose an individual to hypertension. Considering that aging itself is a risk factor for hypertension (44,67), and glomerular filtration rate declines with age (12,14), baseline impairments in renal function combined with sympathetic activation may negatively affect the elderly. Therefore, a better understanding of the renal circulation in older adults may have clinical relevance. However, there is currently little experimental data (42, 61) regarding the effect of healthy aging on renal vasoconstriction during sympathoexcitatory stress.Cold temperatures are seasonally experienced in most regions of the world. The compensatory physiological responses to cold involve the sympathetic nervous ...

Based on available evidence the polypropylene used for surgical treatment of various structural defects is not inert after implantation in the human body. The quest for the perfect mesh must continue.