Prenatal detection and evaluation of an extralobar pulmonary sequestration in the posterior mediastinum.

Extralobar pulmonary sequestration (EPS) is a rare developmental anomaly with aberrant nonfunctioning parenchymal tissue, associated with an increased risk of perinatal morbidity and, rarely, mortality owing to possible neonatal respiratory distress. In most cases supernumerary lobes are detected as isolated intra- or extrapleural lesions with independent systemic arterial blood supply. We report an atypical case of prenatal detection and perinatal outcome of a mediastinal EPS.     

Acute renal haemodynamic effects of radiocontrast media in patients undergoing left ventricular and coronary angiography.

BACKGROUND: Tubular toxicity and renal ischaemia have been implicated in the pathogenesis of radiocontrast media induced nephropathy (CIN), but their respective role remains unclear. Aims. In order to evaluate changes in renal blood flow in response to intra-arterial contrast media administration, we aimed to continuously measure renal arterial perfusion by means of renal blood flow velocity (RBFV) during left ventricular and coronary angiography and subsequent coronary intervention in patients with chronic kidney disease (CKD). Patients and METHODS: Ten patients (7 males, 63.4 +/- 11.7 years) with serum creatinine (SCr) >1.5 mg/dl participated in the study. The first five patients received low-osmolar iopromide and the others iso-osmolar iodixanol contrast medium. RBFV was measured using a 0.014-inch Doppler guide wire, which was inserted through a separate contralateral femoral sheath via a 5 F Cobra diagnostic catheter into the renal artery. Data were recorded at 500 Hz to allow beat-to-beat analysis of RBFV and pressure. All patients were pre-treated with acetylcysteine and hydration. RESULTS: Immediately after left ventricular angiography no significant changes in RBFV were detected. Over time, however, following repeated administration of the additional contrast medium into the coronary arteries, RBFV decreased significantly from baseline until the end of the investigation, 28.4 (19.1/42.7) to 22.9 (16.9/30.6) cm/s (median and quartiles; P = 0.005), in the absence of significant changes in systemic arterial blood pressure. In individual patients the reduction in RBVF varied from 3.7% to 39.5%. On average the decline in RBFV was more pronounced in patients receiving iopromide (from 41.6 cm/s to 29.3 cm/s) than in those receiving iodixanol (from 19.3 to 17.8 cm/s; P = 0.008 for the difference of relative decline). However, in the iopromide treated patients, coronary intervention was more frequently performed (5/5 versus 2/5) and the median duration of the procedure tended to be longer [85 (32-150) min versus 38 (27-110) min; P > 0.2]. CONCLUSIONS: The administration of non-ionic low-osmolal contrast media has no immediate effect on renal perfusion in patients with CKD. However, during the course of coronary angiography a gradual decline in renal blood flow may occur, the extent of which varies, presumably depending on individual pre-disposition as well as on the amount of the contrast medium.     

Estrogen disrupts the inhibition of fear in female rats, possibly through the antagonistic effects of estrogen receptor alpha (ERalpha) and ERbeta

The ambiguous role of estrogen in emotional learning may result from opposing actions of estrogen receptor alpha (ERalpha) and ERbeta. Using a fear-conditioning paradigm called the AX+, BX- discrimination, in which cue A comes to elicit fear and cue B becomes a safety signal, we examined the effect of 17beta-estradiol (E) and selective ERalpha and ERbeta agonists on excitatory and inhibitory fear learning. Gonadectomized (GDX) male and female rats implanted with E or selective ERalpha or ERbeta agonists were trained on the AX+, BX- discrimination and tested periodically to A, B, and AB. GDX sham-implanted male and female rats and GDX E-implanted males, but not GDX E-implanted females, exhibited less fear to AB than to A, suggesting that estrogen interferes with generalization of safety signals in female rats. ERalpha and ERbeta agonists disrupted discrimination learning in both sexes. ERalpha-implanted groups had higher fear responses to all cues than did ERbeta-implanted groups, suggesting that these two receptors have opposing effects in aversive discrimination learning. In contrast, neither E nor ERalpha and ERbeta agonists affected single-cue fear conditioning in either sex. These data suggest that E does not enhance fear in emotional learning but acts to disrupt the inhibition of fear in females only.     

Bombesin-induced hypothermia in rats tested at normal ambient temperatures: Contribution of the sympathetic nervous system

Rats infused centrally with bombesin become hypothermic at normal ambient temperatures when acutely deprived of food, but not while allowed unrestrained access to food. Ad lib-fed rats, tested at normal ambient temperatures, become hypothermic after receiving intracerebroventricular (ICV) bombesin when they have ventromedial hypothalamic lesions or when administered insulin or 2-deoxy-d-glucose peripherally. All of these conditions have been linked to reductions of sympathetic nervous system activity to brown adipose tissue (BAT), a major thermogenic mechanism of many homeotherms. A between group design was used to examine the effects of ICV bombesin infusions on the response to peripheral injections of a) the sympathetic ganglionic blocker chlorisondamine (2.5 mg/kg, IP) in ad lib-fed rats, b) the nonspecific β-agonist isoproterenol (30 mg/kg, IP) in food-deprived rats, and c) the combination of isoproterenol and chlorisondamine in ad lib-fed rats. Ad libfed rats receiving ICV bombesin (100 ng/5 μl), in combination with peripheral chlorisondamine injection, became hypothermic 60 min postbombesin administration (−2.84 ± 0.33°C), while ad lib-fed rats receiving ICV bombesin infusion and peripheral injections of saline did not (−0.08 ± 0.37°C). Isoproterenol blocked hypothermia in ad lib-fed rats injected with chlorisondamine and ICV bombesin. Food-deprived rats receiving ICV bombesin infusion and peripheral saline injection exhibited hypothermia 60 min postbombesin administration (−2.51 ± 0.29°C). Peripheral injections of isoproterenol prevented bombesin-induced hypothermia in food-deprived rats. These data suggest that bombesin induces hypothermia at normal ambient temperatures when the sympathetic nervous system drive to BAT cannot be (or is not) activated.