Hyperglycemia requiring insulin during acute lymphoblastic leukemia induction chemotherapy is associated with increased adverse outcomes and healthcare costs.

BACKGROUND: Hyperglycemia is a complication of induction chemotherapy in 10%-50% of pediatric patients with acute lymphoblastic leukemia (ALL). Though hyperglycemia in ALL patients is usually transient, it may be associated with adverse health outcomes. However, the risk factors for and consequences of hyperglycemia are poorly understood. We hypothesized that hyperglycemia significant enough to require insulin therapy during induction chemotherapy would be associated with increased morbidity and mortality in pediatric ALL patients during induction chemotherapy and in subsequent care. METHODS: We abstracted clinical and resource utilization data from the Pediatric Health Information System (PHIS) database utilizing ICD-9 codes and medication charges. We used logistic regression analysis to predict the development of hyperglycemia. The effects of hyperglycemia on binary and count adverse outcomes following induction chemotherapy were modeled using mixed-effect regression models. RESULTS: An increased risk of hyperglycemia requiring insulin was associated with older age, female sex, higher risk group and trisomy 21. Patients on insulin for hyperglycemia had increased mortality following induction chemotherapy. These patients were more likely to have subsequent infectious complications, need for bone marrow transplant, and risk of disease relapse. They also had greater length of inpatient stay, higher cost of care, and were more likely to require intensive care unit admission during induction chemotherapy. CONCLUSIONS: Hyperglycemia requiring insulin during induction chemotherapy in pediatric ALL is associated with an increased risk of short-term and long-term complications. Prospective studies are needed to analyze formal screening, preventive measures, and optimal management practices for hyperglycemia during ALL induction chemotherapy.

Improving the Evaluation and Management of Abnormal Uterine Bleeding in Female Adolescents Presenting for Emergency Care.

STUDY OBJECTIVE: We sought to improve emergency care for adolescents with abnormal uterine bleeding (AUB) by developing a clinical effectiveness guideline (CEG) and assessing its effect on quality of care. DESIGN, SETTING, PARTICIPANTS, AND INTERVENTIONS: A stakeholder engagement group designed a CEG algorithm for emergency AUB management. Pediatric residents received CEG training and their knowledge and attitudes were assessed using pre- and post intervention surveys. International Classification of Diseases ninth and 10th revision codes identified electronic health record data for patients who presented to the pediatric emergency department for AUB 6 months before and after CEG implementation. A weighted, 20-point scoring system consisting of prioritized aspects of history, laboratory studies, and management was developed to quantify the quality of care provided. MAIN OUTCOME MEASURES: Descriptive statistics, χ2 test, Wilcoxon rank sum test, and a run chart were used for analysis. RESULTS: Pediatric residents reported higher confidence and knowledge scores post CEG implementation. Of the 91 patients identified, 62 met inclusion criteria. Median score was 14 ± 7 before CEG implementation and 15.5 ± 6 after. The Wilcoxon rank sum test showed a difference in AUB evaluation and management scores (P = .09) after implementation of the CEG. Run chart data showed no shifts or trends (overall median score, 14 points). Pre- and post implementation, points were deducted most frequently for not assessing personal/family clotting disorder history. The largest improvements in care were with appropriate medication dosing and disposition. CONCLUSION: We designed a CEG and educational intervention for AUB management in a pediatric emergency department. These findings suggest our CEG might be an effective tool to improve emergency AUB care for adolescents and could increase trainees' confidence in managing this condition, although additional cycles are needed.

Understanding intrinsically irreversible, non-Nernstian, two-electron redox processes: a combined experimental and computational study of the electrochemical activation of platinum(IV) antitumor prodrugs.

Six-coordinate Pt(IV)-complexes are prominent prodrug candidates for the treatment of various cancers where, upon two-electron reduction and loss of two axial ligands, they form more familiar, pharmacologically active four-coordinate Pt(II) drugs. A series of electrochemical experiments coupled with extensive density functional calculations has been employed to elucidate the mechanism for the two-electron reduction of Pt(IV)(NH3)2Cl2L2 to Pt(II)(NH3)2Cl2 (L = CH3COO(-), 1; L = CHCl2COO(-), 2; L = Cl(-), 3). A reliable estimate for the normal reduction potential E(o) is derived for the electrochemically irreversible Pt(IV) reduction and is compared directly to the quantum chemically calculated reduction potentials. The process of electron transfer and Pt-L bond cleavage is found to occur in a stepwise fashion, suggesting that a metastable six-coordinate Pt(III) intermediate is formed upon addition of a single electron, and the loss of both axial ligands is associated with the second electron transfer. The quantum chemically calculated reduction potentials are in excellent agreement with experimentally determined values that are notably more positive than peak potentials reported previously for 1-3.

Not physically present contours can yield illusory motion.

We demonstrate a perceptual effect whereby contours not physically present in a visual scene can yield striking illusory motion. The not physically present contours are paths of invariant contrast polarity (CP). For example, when a square checkerboard composed of dark and light square checks with small black and white discs covering the vertices is put in lateral motion, there is the striking perception of vertical expansion/contraction. Such a checkerboard has (not physically present) diagonal paths of CP presentation with vertical components. However, when a square checkerboard made up of square black and very light checks with gray discs of luminance intermediate to the checks is put in lateral motion, no expansion/contraction is seen. For this checkerboard the vertical components of paths of CP preservation cancel each other out, predicting the lack of perception of vertical expansion/contraction. We also discuss how not physically present contours can explain previously described effects and suggest new effects to be explored.

Contrast polarity preservation's role in perception: explained and unexplained stimuli.

Roncato and Casco (2003, Perception & psychophysics 65 1252-1272) had shown that in situations where the Gestalt principle of good continuity is put into conflict with preservation of contrast polarity (CP) the perception that preserves CP prevails. Parlangeli and Roncato (2010, Perception 39 255-259) have studied this question of preservation of CP more closely and have added an addendum to the rule. They have used stimuli consisting of a checkerboard of perpendicularly arranged rectangular bricks (white, gray, or black) and draughtsmen white, gray, or black disks placed at the corners of the bricks. This study has caused them to add an addendum to the rule of CP-preserved path-conjunction binding: if there are two contour completions that preserve the CP, the one with the higher contrast will prevail. Parlangeli and Roncato find that, for certain shades of the disks and bricks, the perpendicular lines of the checkerboard appear strikingly to be slanted or undulating. Here we consider all possible arrangements of relative magnitudes of checkerboards consisting of bricks of two different shades and disks of two shades as well, as such arrangements with widely varying differences in the magnitude of brightness. We have found a number of cases where the perception is not explained by the rule and addendum of Roncato and Casco, and Parlangeli and Roncato, and a case where preservation of "distant" as well as local CP plays a role in perception. The previously known cases, and the new exceptional unexplained stimuli we have found, warrant further study.

Forensic utility of isotope ratio analysis of the explosive urea nitrate and its precursors.

Urea nitrate (UN) is an improvised explosive made from readily available materials. The carbon and nitrogen isotope composition of UN and its component ions, urea and nitrate, could aid in a forensic investigation. A method was developed to separate UN into its component ions for δ(15)N measurements by dissolving the sample with KOH, drying the sample, followed by removal of the urea by dissolution into 100% methanol. UN was synthesized to assess for preservation of the carbon and nitrogen isotope compositions of reactants (urea and nitric acid) and product UN. Based on nitrogen isotope mass balance, all UN samples contained varying amounts of excess nitric acid, making the ionic separation an essential step in the nitrogen isotope analysis. During UN synthesis experiments, isotopic composition of the reactants is preserved in the product UN, but the urea in the product UN is slightly enriched in (15)N (<1‰) relative to the reactant urea. Published isotopic compositions of UN reactants, urea and nitric acid, have large ranges (urea δ(15)N = -10.8 to +3.3‰; urea δ(13)C = -18.2 to -50.6‰; and nitric acid δ(15)N = -1.8 to +4.0‰). The preservation of isotopic composition of reactants in UN, along with a significant variability in isotopic composition of reactants, indicates that isotope ratio analysis may be used to test if urea or nitric acid collected during an investigation is a possible reactant for a specific UN sample. The carbon and nitrogen isotope ratios differ significantly between two field-collected UN samples, as well as the lab-synthesized UN samples. These observed variations suggest that this approach is useful for discriminating between materials which are otherwise chemically identical.

Koffka's effect is mediated by figure thickness at the joining region.

Three-quarters of a century ago Gestalt psychologist Kurt Koffka described a remarkable effect: when a contiguous gray ring is placed on a background half one shade of gray, half another, the ring appears homogeneous. However, if the ring is divided, the two halves of the ring appear different shades of gray, the half of the ring on the darker background appearing lighter than the half of the ring on the lighter background. The Gestalt principle of continuity is used to explain this effect. But what microscopic principles might be mediating this effect? Recently we found sufficiently thin rings (annuli) appear heterogeneous even when geometrically continuous. Here, using crescent-shaped figures instead of the circular annuli used for the traditional Koffka effect, we show that this effect of thickness of the ring is mediated by the thickness at the boundary of the region where the halves of the figure are joined.