Resection of the irradiated esophagus: the impact of lymph node yield on survival.

There is debate surrounding the appropriate threshold for lymph node harvest during esophagectomy in patients with esophageal cancer, specifically for those receiving preoperative radiation. The purpose of this study was to determine the impact of lymph node yield on survival in patients receiving preoperative chemoradiation for esophageal cancer. The National Cancer Database (NCDB) was utilized to identify patients with esophageal cancer that received preoperative radiation. The cohort was divided into patients undergoing minimal (<9) or extensive (≥9) lymph node yield. Demographic, operative, and postoperative outcomes were compared between the groups. Kaplan-Meier analysis with the log rank test was used to compare survival between the yield groups. Cox proportional hazards model was used to determine the association between lymph node yield and survival. In total, 886 cases were included: 349 (39%) belonging to the minimal node group and 537 (61%) to the extensive group. Unadjusted 5-year survival was similar between the minimal and extensive groups, respectively (37.3% vs. 38.8%; P > 0.05). After adjustment using Cox regression, extensive lymph node yield was associated with survival (hazard ratio 0.80, confidence interval 0.66-0.98, P = 0.03). This study suggests that extensive lymph node yield is advantageous for patients with esophageal cancer undergoing esophagectomy following induction therapy. This most likely reflects improved diagnosis and staging with extensive yield.

A randomised, controlled trial comparing the Airtraq™ optical laryngoscope with conventional laryngoscopy in infants and children.

The Airtraq(™) optical laryngoscope became available in paediatric sizes in the UK in May 2008. We conducted a randomised, controlled trial comparing the Airtraq with conventional laryngoscopy during routine anaesthesia in children. We hypothesised that the Airtraq laryngoscope would perform as well as conventional laryngoscopy. Sixty patients (20 infants and 40 children) were recruited. The mean (SD) intubation time using the Airtraq was longer than conventional laryngoscopy overall (47.3 (32.6) vs 26.3 (11.5) s; p=0.002), though the difference was only significant for children (p=0.003) and not for infants (p=0.29). The Airtraq provided a better view of the larynx compared with conventional laryngoscopy (in infants (percentage of glottic opening scores 100 (95-100 [90-100]) vs 77 (50-90 [40-100]), respectively; p=0.001; visual analogue scores for field of view 9.2 (9.2-9.5 [8.2-10.0]) vs 6.8 (5.1-8.0 [4.7-10.0]), respectively; p=0.001). In children, the Airtraq provided a similar view of the larynx (percentage of glottic opening scores 100 (100-100 [40-100]) vs 100 (90-100 [50-100]), respectively; visual analogue scores for field of view 9.2 (8.6-10.0 [7.0-10.0]) vs 9.2 (8.6-10.0 [5.6-10.0]), respectively; both p>0.05), compared with conventional laryngoscopy.

Glucocorticoids enhance histamine-evoked catecholamine secretion from bovine chromaffin cells.

The synthetic glucocorticoid dexamethasone enhanced histamine-evoked catecholamine secretion from cultured bovine chromaffin cells. Dexamethasone enhanced the effects of histamine on both adrenergic (epinephrine-rich) and noradrenergic (norepinephrine-rich) chromaffin cells but had a more dramatic effect on noradrenergic cells. Histamine-evoked secretion in noradrenergic cells appeared to become rapidly inactivated, whereas the rate of secretion in adrenergic cells was nearly constant for up to 2 h; dexamethasone treatment attenuated the inactivation seen in noradrenergic cells. The effect of dexamethasone appeared after a lag of several hours and was maximal by 24 h. The EC50 for dexamethasone was approximately 1 nM. The effect of dexamethasone was mimicked by the glucocorticoid agonist RU 28362 and was blocked by the antagonist RU 38486, indicating that the effects of these steroids were mediated by the glucocorticoid or type II corticosteroid receptor. Histamine-evoked catecholamine secretion in both dexamethasone-treated and untreated cells was blocked by the H1 histamine receptor antagonist mepyramine but was not affected by the H2 antagonist cimetidine; thus, dexamethasone appeared to enhance an H1 receptor-mediated process. In the absence of glucocorticoids, H1 receptor mRNA levels were higher in adrenergic than in noradrenergic cells. Dexamethasone increased H1 receptor mRNA levels in both cell types. The increased expression of H1 receptors presumably contributes to the enhancement of histamine-evoked catecholamine secretion by glucocorticoids. Glucocorticoids may play a physiological role in modulating the responsiveness of chromaffin cells to histamine and other stimuli.

Histamine evokes greater increases in phosphatidylinositol metabolism and catecholamine secretion in epinephrine-containing than in norepinephrine-containing chromaffin cells.

Chromaffin cells have H1 histamine receptors. Histamine, acting at these receptors, increases the metabolism of inositol-containing phospholipids and stimulates catecholamine secretion from chromaffin cells. We have investigated the effects of histamine and other agents on the accumulation of inositol monophosphate (InsP1) and catecholamine secretion in purified cultures of norepinephrine-containing and epinephrine-containing bovine chromaffin cells. Histamine-stimulated InsP1 accumulation in epinephrine cells was three times greater than that in norepinephrine cells. In contrast, bradykinin caused roughly equivalent increases in InsP1 accumulation in the two chromaffin cell subtypes. Histamine-stimulated catecholamine secretion was also greater in epinephrine cells than in norepinephrine cells, whereas high K+, bradykinin, phorbol 12,13-dibutyrate, and angiotensin II all caused greater secretion from norepinephrine cells than from epinephrine cells. The density of H1 receptors in epinephrine cells was approximately three times greater than that in norepinephrine cells. The greater density of H1 receptors on epinephrine cells may account for the greater effects of histamine on InsP1 accumulation and catecholamine secretion in these cells.

Intact "biological motion" and "structure from motion" perception in a patient with impaired motion mechanisms: a case study.

A series of psychophysical tests examining early and later aspects of image-motion processing were conducted in a patient with bilateral lesions involving the posterior visual pathways, affecting the lateral parietal-temporal-occipital cortex and the underlying white matter (as shown by magnetic resonance imaging studies and confirmed by neuro-ophthalmological and neuropsychological examinations). Visual acuity, form discrimination, color, and contrast-sensitivity discrimination were normal whereas spatial localization, line bisection, depth, and binocular stereopsis were severely impaired. Performance on early motion tasks was very poor. These include seeing coherent motion in random noise (Newsome & Paré, 1988), speed discrimination, and seeing two-dimensional form from relative speed of motion. However, on higher-order motion tasks the patient was able to identify actions from the evolving pattern of dots placed at the joints of a human actor (Johansson, 1973) as well as discriminating three-dimensional structure of a cylinder from motion in a dynamic random-dot field. The pattern of these results is at odds with the hypothesis that precise metrical comparison of early motion measurements is necessary for higher-order "structure from motion" tasks.