Poisoning Through Pediatric Skin: Cases from the Literature

Poisoning through pediatric skin leading to acute systemic symptoms is a relatively uncommonly reported phenomenon. Systemic toxicity through the skin typically occurs by direct contact between therapeutic or non-therapeutic topical agents and the skin. Though uncommon, poisoning through pediatric skin can have significant consequences and must be recognized so the offending agent may be discontinued and appropriate treatment initiated. We performed a literature search for all article types between 1950 and April 2016 to provide a single source of detectable cases of acute toxicity in pediatric patients due to percutaneous exposure. This literature review discusses relevant pediatric skin physiology along with reports of poisoning events that resulted in systemic signs and symptoms and even death to provide a comprehensive report on causes of pediatric poisoning through the skin

Influence of different angles of file access on cyclic fatigue resistance of 2shape rotary instruments in different artificial canals

Aim: Several parameters including extent of the curvature and angulated insertion of file into the canal could influence cyclic fatigue of nickel-titanium files. The purpose of this study was to compare the influence of different access angles associated to different curvature radii on cyclic fatigue resistance of 2Shape (TS; Micro-Mega, Besancon, France) rotary instruments. Methods: 60 instruments were tested in two 16mm- stainless steel artificial canals with angle of curvature of 60° and 5mm or 3mm radius of curvature respectively. 2Shape TS2 #25.06 and 2Shape TS1 #25.04 were evaluated at 0°, 10° and 20° insertion angles (n=10 for each angle of access). Cyclic fatigue resistance was determined by Number of Cycles to Failure (NCF) using a new testing device machine. This device consists of a platform composed of a block containing the electric handpiece and a mobile support on rails for insertion/disconnection of the file. Moreover, a metal mobile platform is connected to the mobile support. This second platform with the artificial canal produces the different inclination of insertion of tested file maintaining the entrance of instrument perpendicular to the canal. Each instrument was tested in continuous rotation (300 rpm) following the manufacturer’s instructions. Fracture surface was examined with a scanning electron microscope. Data were statistically analyzed using 2-way analysis of variance and the Bonferroni multiple comparison post-hoc test (Prism 7.0; GraphPad Software, Inc, La Jolla, CA) with a significance level of P<0.05. Results: TS1 (#25.04) exhibited higher cyclic fatigue resistance than TS2 (#25.06) for each angle and radius tested (P<0.05). When files were tested inside 3mm- radius canal, independently from taper, they recorded lower cyclic fatigue resistance than in 5mm-radius one (P<0.05). Considering canal with 5mm-radius of curvature, no significant cyclic fatigue resistance reduction was observed for .06 taper-instruments for each angle tested (P>0.05), while files with .04 taper exhibited significant lower NCF when tested at 20° (P<0.05). In canals with 3mm radius of curvature, TS2 (#25.06) showed no significant differences for each angle tested (P>0.05). TS1 (#25.04) exhibited significant resistance reduction between 0° and 10° as well as between 0° and 20° (P<0.05), with no difference between 10° and 20° (P>0.05). Conclusion: Inclined angle of file access into the canals decreased cyclic fatigue resistance of #25.04 files especially when the radius of curvature is reduced. Cyclic fatigue resistance of #25.04 instruments was higher than #25.06 files made with the same thermal treatment. Independently from taper, each file tested in 3mm-radius canal showed lower cyclic fatigue resistance than instruments tested in 5mm-radius canal

COX-2 expression in ampullary carcinoma: correlation with angiogenesis process and clinicopathological variables

BACKGROUND: There is evidence that the anti-neoplastic effect of non-steroidal anti-inflammatory drugs is attributable to cyclooxygenase-2 (COX-2) inhibition, but the exact mechanisms whereby COX-2 can promote tumour cell growth remain unclear. One hypothesis is the stimulation of tumour angiogenesis by the products of COX-2 activity. To data, there have been few clinicopathological studies on COX-2 expression in human ampullary carcinoma and no data have been reported about its relation with tumour angiogenesis. Objective: To investigate by immunohistochemistry the expression of COX-2 and the angiogenesis process in a series of primary untreated ampullary carcinomas.METHODS: Tissue samples from 40 archival ampullary carcinomas were analysed for COX-2, vascular endothelial growth factor (VEGF), and an endothelial cell marker von Willebrand factor (vWF) by immunohistochemistry, using specific antibodies.RESULTS: COX-2 expression was detected in 39 tissue samples (97.5%), of which two (5%) were graded as weak, 26 (65%) as moderate, and 11 (27.5%) as strong. Only one lesion (2.5%) was negative for COX-2 expression. VEGF expression was detected in 36 tissue samples (90%). A significant positive correlation was found between COX-2 and VEGF expression. No statistic correlation was found between COX-2 expression and microvessel density.CONCLUSIONS: COX-2 is highly expressed in ampullary carcinomas. This suggests an involvement of the COX-2 pathway in ampullary tumour associated angiogenesis, providing a rationale for targeting COX-2 in the treatment of ampullary cancer