Due to increased incidence of pancreaticobiliary disease in children, more pediatric gastroenterologists are performing Endoscopic Retrograde Cholangiopancreatography (ERCP) and Endoscopic Ultrasound (EUS). Many of these procedures are safely performed by appropriately trained pediatric advanced endoscopists (PAE) at pediatric facilities, but there is a lack of literature characterizing their training environment. The aim of this study is to describe practicing PAE's training experiences in the United States.

Preeclamptic women produce agonistic autoantibodies to the Angiotensin II type 1 receptor (AT1-AA) and exhibit increased sensitivity to angiotensin II (ANG II). Together, AT1-AA and ANGII increased blood pressure, endothelin-1 (ET-1), oxidative stress in pregnant rats. However, cellular mechanisms for such responses remain unknown. Our objective in this study was to examine the effect of AT1-AA on ANGII binding to the AT1 receptor on human vascular umbilical endothelial cells (HUVEC) and the subsequent release of ET-1. Methods: HUVECs were incubated for 1 hour with FITC labelled ANGII (10nM, 50nM, 100nM and 200nM) with or without AT1-AA (1:100), losartan [LOS (10µM)], or a specific inhibitor of AT1-AAs [7AA(5µg/ml)]. ANGII binding was determined by FITC labeled ANGII florescence at 490nm excitation and 522nm emission wavelengths and ET-1 was measured by ELISA. Results: At 1 hour incubation, bound ANG II to AT1 R was approximately 1.0+/-0.11 and 5.2±1.3 pmols/mg at 100 and 200 nM concentrations, which drastically increased with the AT1-AA to 20+/-5 and 65+/-3, and was decreased with AT1-AA inhibitory peptide (40 +/-3 at the 200nM ANGII) and losartan. Interestingly, AT1-AA induced a 2-fold increase in ET-1 above that with ANGII alone at physiological doses of 10nM and 50nM, which sharply declined at higher doses of ANGII (100, 200 & 500nM). Conclusion AT1-AA greatly increases the binding affinity of ANGII for the AT1 R on HUVECs and secretion of ET-1 at physiological ANGII concentrations supporting a role for the AT1-AA to enhance ANGII effects during preeclampsia.

Fever following pediatric endoscopic procedures is one of the most common adverse events encountered, causing concern for perforation and/or significant infection as a complication of endoscopy. As a result, patients are often referred to the emergency department or receive other unanticipated evaluation for further assessment. Results of these evaluations are almost uniformly normal yet lead to additional costs and interventions.

Cytochrome P450 (CYP)-mediated desulfuration of methyl parathion results in mechanism-based inhibition of the enzyme. Although previous data suggest that reactive sulfur is released and binds to the apoprotein, the identities of neither the adduct(s) nor the affected amino acid(s) have been clearly determined. In this study, nanospray tandem mass spectroscopy was used to analyze peptide digests of CYP resolved by SDS-PAGE from liver microsomes of male rats following incubation in the absence or presence of methyl parathion. Oxidative desulfuration was confirmed by measurement of methyl paraoxon, and inhibition of specific CYP isozymes was determined by measurement of testosterone hydroxylation. Total CYP content was quantified spectrophotometrically. Incubation of microsomes with methyl parathion decreased CYP content by 58%. This effect was not associated with a comparable increase in absorbance at 420 nm, suggesting the displacement of heme from the apoprotein. Rates of testosterone 2β- and 6β-hydroxylation, respectively, were reduced to 8 and 2%, implicating CYP3A and CYP2C11 in the oxidative desulfuration of methyl parathion. Mass spectrometric analysis identified 96 amu adducts to cysteines 64 and 378 of CYP3A1. In addition, a peptide containing cysteine 433 that coordinates with heme was possibly modified as it was detected in control, but not methyl parathion samples. A comparison of rat CYP3A1 with human CYP3A4 suggests that cysteines 64 and 378 reside along the substrate channel, remote from the active site. Alteration of these residues might modulate substrate entry to the binding pocket of the enzyme.

Fluorescence has recently been applied to the analysis of the molecular organization state of the polyene antibiotic amphotericin B (AmB) in solution or in lipid membranes. The polyene chain of AmB monomer gives rise to two fluorescence emissions; S 1 (2 1 A g ) → S 0 (1 1 A g ) between 500 and 700 nm, S 2 (1 1 B u ) → S 0 (1 1 A g ) between 400 and 500 nm. However, Raman scattering might interfere with the S 2 → S 0 emission fluorescence due to the weak fluorescence quantum yield and close proximity to the exciting lines. In fact, we show here that a change in the excitation wavelength results in a shift of three emission bands, an effect which excludes their assignment to fluorescence. These bands originate from the water Raman at 3382 cm -1 and AmB resonance Raman at 1556 and 1153 cm -1 . As a consequence, some former conclusions on the molecular organization state of AmB should be reconsidered.

The objective was to assess the learning outcomes and student satisfaction with an ANS pharmacology module taught in a modified team‐based learning (MTBL) format combined with high fidelity simulation.

OBJECTIVES:Based on the assertion that fluorescence spectroscopy detects dimers of the polyene antibiotic amphotericin B (AmB), this technique was recently proposed to analyse the interaction of the drug with cell membranes. However, contradictory results indicate that this 'dimeric' fluorescence might actually originate from polyene impurities. We used a highly purified AmB to challenge this last proposal.METHODS:Comparison of the fluorescence of AmB from different origins was made in dimethyl sulphoxide (DMSO); concentration and sodium dodecyl sulphate (SDS) addition dependencies were analysed in water.RESULTS:Excitation of fluorescence in the absorption band of the AmB monomer (around 410 nm) revealed no difference between the different samples, in contrast with what was observed by excitation in the absorption wavelengths of self-associated AmB (around 325 nm). Furthermore, in this latter case, no concentration dependence was observed, in DMSO or in water. SDS addition increased the fluorescence in water.CONCLUSIONS:The fluorescence of AmB observed by excitation in the absorption wavelengths of self-associated species (around 325 nm) is explainable by the presence of impurities. Fluorescence is probably not appropriate for characterization of the drug interaction with cell membranes.

Liposuction, also known as lipoplasty, liposculpture, andsuction-assisted lipectomy, is a surgical procedure used toremove subcutaneous fat from specific body sites by usinga suction vacuum. The procedure is most commonlyperformed on the buttocks, hips, thighs, and abdomenbut is also frequently used to remove fat from under thechin, neck, breasts, knees, upper arms, calves, and ankles.Liposuction is the most common cosmetic surgical pro-cedure performed in the United States. It is estimated thatmore than 400,000 persons undergo liposuction every year(1). Advances in liposuction technology now make itpossible to remove considerable amounts of subcutaneousfat; in obese subjects, aspiration of*14 kg of fat has been safely performed (2). The purpose of this chapter is toreview the potential use of liposuction as a tool fortreating obesity.

BACKGROUND:Selective cannulation of the common bile duct (CBD) during endoscopic retrograde cholangiopancreatography (ERCP) can be difficult. Several techniques have been described to assist endoscopists in obtaining access when initial cannulation fails. The objective of this report is to describe our initial experience with the "double-wire technique" in the pediatric population.PATIENTS AND METHODS:Sixty ERCPs were performed in children with ages ranging from 8 months to 18 years and the technique was used in 8 cases. After wire-guided access to the pancreatic duct is obtained, the wire is left in place within the pancreatic duct to aid subsequent selective cannulation of the CBD.RESULTS:In 2 of these cases, transient increase in pancreatic enzymes was observed after ERCP. Nevertheless, in this small series of patients it was found to be an effective and useful tool in cases in which repeated attempts have yielded only pancreatic duct cannulation.CONCLUSIONS:This technique is a useful aid for the endoscopist attempting to selectively cannulate the CBD in difficult cases. Further study will be needed to establish the safety of this technique in the pediatric population.

OBJECTIVES Amphotericin B (AmB) is a drug of choice for treatment of disseminated fungal infections, but its use is often associated with severe adverse effects. Our observation that generic formulations of AmB contain multiple polyene components led us to propose that removal of other polyenes would yield a high purity AmB (AmBHP) with an improved therapeutic index. METHODS To test that premise, AmBHP was first isolated from generic AmB by semi-preparative reverse phase high-pressure liquid chromatography and then its effects were compared in vitro and in vivo with those of commercial AmB formulations. RESULTS AmBHP proved to be as active as generic AmB against Candida albicans in vitro and as efficacious as both generic and lipid-complexed AmB in a Candida-infected mouse model. AmBHP appeared to be less toxic to human THP-1 monocytic cells than was generic AmB at low concentrations (<2 microM), as indicated by exclusion of Trypan Blue and incorporation of [(3)H]thymidine. At higher concentrations, effects of AmBHP and generic AmB (Pharma-Tek AmB, PTAmB) on thymidine incorporation and cytosolic calcium concentration were similar. General toxicity to AmBHP in vivo, as indicated by its apparent LD(50) and survival of Candida-infected mice, was roughly twofold less than that to generic or lipid-complexed AmB. Likewise, AmBHP decreased mean glomerular filtration rate about half as much as did a 10-fold lower dose of PTAmB. CONCLUSIONS Taken together, these data indicate that AmBHP may represent a refinement of currently marketed AmB formulations, offering equal, if not better, efficacy with less toxicity.

A method was developed for the quantitation of pentoxifylline [1-(5-oxohexyl)-3,7-dimethylxanthine] and a primary active metabolite, lisofylline [1-(5-hydroxyhexyl)-3,7-dimethylxanthine], using high-performance liquid chromatography (HPLC)-tandem mass spectrometry. This method was developed in order to overcome problems encountered with HPLC-ultraviolet detection. The operating parameters of the electrospray interface (PE SCIEX, TurboIon Spray) and lens voltages of the triple-quadrupole detector (PE SCIEX 365) were optimized in positive ion mode to obtain the best sensitivity of the analytes. Collision-induced dissociation was used to produce fragment ions, and multiple reaction monitoring was used to quantitate pentoxifylline (m/z 279/181) and lisofylline (m/z 263/181). Dichloromethane was used to extract the drug, metabolite, and the internal standard (3-isobutyl-1-methylxanthine) from plasma. A reverse-phase C8(2) 150 x 1.0 mm HPLC column was used to resolve all three compounds in less than 6 min. Calibration curves were generated using peak area and were linear from 1 to 1000 ng/mL (R(2) > 0.99). The small sample volume, ease of extraction, and sensitivity provide advantages over more conventional methods of quantitation.