Recruitment of multiple V beta genes in the TCR repertoire against a single pathogenic thyroglobulin epitope

To better clarify the possible role of immune mechanisms in the pathogenesis of Warthin's tumour (WT), we performed a retrospective study of patients with WT surgically treated at the Institute of Otolaryngology Head and Neck Surgery, University of Florence, during a 25-year period; looking for a possible association with autoimmune pathologies. The retrospective analysis of clinical records of 140 WT patients compared with those of 380 patients with pleomorphic adenoma revealed a higher incidence of autoimmune disorders, particularly organ-specific disease (i.e. insulin-dependent diabetes mellitus, Hashimoto's thyroiditis, autoimmune hyperthyroidism and hypothyroidism) in WT patients than in pleomorphic adenoma (PA) patients (23% vs 3%; R.R.: 8.69; p < 0.0001). Moreover, we demonstrate a positive smoking history in 87% of WT patients compared to only 38% of PA subjects (p < 0.001). Because of the well-known possible association among multiple immune disorders, our data support the hypothesis of an immune pathogenesis of WT and also suggest the possible role of tobacco smoke in facilitating such immune reactions responsible for the lympho-epithelial coexistence of WT.     

Role of preischemic glycogen depletion in the improvement of postischemic metabolic and contractile recovery of ischemia-preconditioned rat hearts

BACKGROUND: Ischemic preconditioning (IPC) attenuates acidosis during prolonged ischemia and improves contractile and metabolic parameters during subsequent reperfusion. Glycogen depletion induced by IPC is proposed as a potential mechanism. METHODS AND RESULTS: We studied the influence of manipulations of preischemic glycogen levels (Pre-G, micromol glucose/g wet wt) on contractile and metabolic (via 31P-nuclear magnetic resonance) parameters during 30 minutes of ischemia and recovery in four groups of isovolumic rat hearts: First, control (Con, n=18, mean Pre-G, 21.5+/-0.8); second, after two 5-minute IPC periods (IPC, n=12, Pre-G, 11.3+/-0.7); third, a control group in which Pre-G was depleted by glucose-free, acetate perfusion (Con-LowG, n=9, Pre-G, 7.9+/-1.2); and fourth, an IPC group in which Pre-G was raised by glucose and lactate perfusion such that Pre-G was similar to Con (IPC-HiG, n=11, Pre-G, 20+/-1.4). Manipulation of Pre-G significantly altered the pH fall during 30 minutes of ischemia (Con, 5.76+/-.03, Con-LowG, 6.26+/-.07; IPC-HiG, 5.91+/-.02, IPC, 6.05+/-.09). IPC-HiG hearts had significantly worse metabolic recovery (PCr, 70+/-7 versus 91+/-3% initial; IPC-HiG versus IPC, P<.05) and contractile recovery (end-diastolic pressure, 52+/-5 versus 29+/-5 mm Hg, P<.05) than IPC hearts but better recovery than Con (%PCr, 56+/-6% and end-diastolic pressure, 72+/-6 mm Hg). An ischemic rise in intracellular magnesium occurred and was atttenuated in preconditioned hearts. CONCLUSIONS: Pre-G levels before ischemia influence but are not the sole determinants of the extent of acidosis during prolonged ischemia and of metabolic and contractile recovery during reperfusion in control and preconditioned hearts.     

Cocaine augments contractility of the pregnant human uterus by both adrenergic and nonadrenergic mechanisms

Airbag injuries have resulted in the deaths of several infants and small children, and such deaths are generally associated with rearward-facing infant seats or unrestrained children in front passenger seats of cars equipped with airbags. An airbag can also cause death in a small child wearing a shoulder/lap belt, however, as this case report illustrates. A two-year-old female was involved in a low-speed collision while riding in the front passenger seat of a dual-airbag-equipped automobile. Secondary impact with the airbag caused catastrophic occipitoatlantoaxial disarticulation with traumatic spinal cord separation, thermal injury and abrasions of the right forearm and distinctive patterned abrasions of the face. The possibility of airbag injury should be considered in all low-speed traffic fatalities, and the confirmatory injuries sought at postmortem examination.     

Evaluation and management of bilateral renal artery stenosis in children: a case series and review

This report describes the clinical course, diagnostic evaluation and management of six children with bilateral renal artery stenosis (RAS) and concurrent narrowing of the abdominal aorta. Except for one child with active arteritis, the others were asymptomatic. There were no clinical or laboratory features suggesting the etiology of hypertension in four of six patients, and diagnostic procedures, including Doppler duplex ultrasound and captopril scintigraphy, were unreliable in screening for such hypertension. Abdominal aortography and selective renal angiography confirmed the diagnosis of bilateral RAS and associated anatomical alterations of the aorta and its branches. The hypertension was severe and minimally responsive to antihypertensive agents. It was cured or improved after percutaneous transluminal angioplasty (PTA) of three vessels in two children with mid-vessel stenoses, while hypertension persisted after PTA of two mid-vessel stenoses in a third child and one vessel with ostium stenosis in a fourth child. Autotransplantation of seven kidneys in four children resulted in cure of significant improvement of the hypertension. Renal function was preserved in all children during a mean follow-up time of 41 months. Based on illustrative data from these six children, as well as information from a review of the literature, this report discusses the key diagnostic issues and stresses the potential advantages of renal autotransplantation in selected children with this disorder.     

Treatment of recurrent corneal erosion using phototherapeutic keratectomy with the excimer laser

Tachyphylaxis to methacholine has been reported in nonasthmatic subjects. In a recent study on the prevalence of airway hyperresponsiveness (AHR) and atopy, we performed duplicate methacholine inhalation tests at a 60-min interval, in subjects with symptomatic asthma (n = 33), asymptomatic AHR (AAHR) (n = 72) and in a group of normal subjects (n = 130); 135/235 subjects were atopic. All subjects had a respiratory questionnaire, allergy skin prick tests, blood eosinophil counts and determination of total serum IgE level. In asthmatic subjects, PC20 just failed to be significantly higher on a second methacholine challenge (p = 0.09); when they were stratified according to severity of AHR and use of inhaled corticosteroids, we observed a significant increase in PC20 on the second test in asthmatic subjects with mild AHR not using corticosteroids (p < 0.01). In normal controls, PC20 methacholine was slightly increased on rechallenge (p < 0.01) as it was in those with AAHR (p < 0.01). There was no relationship between the magnitude of the change in PC20 and age, sex, baseline airway responsiveness, percent fall in FEV1 on the first challenge, atopic score, blood eosinophil counts and serum IgE levels. In conclusion, tachyphylaxis to methacholine is observed in normal or mild asthmatic subjects not using inhaled corticosteroids and in subjects with AAHR; however, in most subjects this change is of a small magnitude.