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Nutrition plays an important role in health promotion and disease prevention and treatment across the lifespan. Physicians and other healthcare professionals are expected to counsel patients about nutrition, but recent surveys report minimal to no improvements in medical nutrition education in US medical schools. A workshop sponsored by the National Heart, Lung, and Blood Institute addressed this gap in knowledge by convening experts in clinical and academic health professional schools. Representatives from the National Board of Medical Examiners, the Accreditation Council for Graduate Medical Education, the Liaison Committee on Medical Education, and the American Society for Nutrition provided relevant presentations. Reported is an overview of lessons learned from nutrition education efforts in medical schools and health professional schools including interprofessional domains and competency-based nutrition education. Proposed is a framework for coordinating activities of various entities using a public-private partnership platform. Recommendations for nutrition research and accreditation are provided.

Appeals for health equity call for departments of pediatrics to improve the health of all children including those from underserved communities in North America and around the world. Consequently, North American (NA) departments of pediatrics have a role in global child health (GCH) which focuses on providing health care to underserved children worldwide. In this review, we describe how NA departments of pediatrics can collaboratively engage in GCH education, clinical practice, research, and advocacy and summarize best practices, challenges, and next steps for engaging in GCH in each of these areas. For GCH in low- and middle-income countries (LMICs), best practices start with the establishment of ethical, equitable, and collaborative partnerships with LMIC communities, organizations, and institutions engaged in GCH who are responsible for the vast majority of work done in GCH. Other best practices include adequate preparation of trainees and clinicians for GCH experiences; alignment with local clinical and research priorities; contributions to local professional development and ongoing monitoring and evaluation. Challenges for departments include generating funding for GCH activities; recruitment and retention of GCH-focused faculty members; and challenges meeting best practices, particularly adequate preparation of trainees and clinicians and ensuring mutual benefit and reciprocity in NA–LMIC collaborations. We provide examples of how departments have overcome these challenges and suggest next steps for development of the role of NA departments of pediatrics in GCH. Collaborative implementation of best practices in GCH by LMIC–NA partnerships can contribute to reductions of child mortality and morbidity globally.

To characterize and compare acid suppression (pharmacodynamics) and pharmacokinetics of IV famotidine and ranitidine in critically ill children at risk for stress gastritis. Single-blind, randomized study in PICU patients 6 months to 18 years requiring mechanical ventilation with continuous gastric pH monitoring, randomized to IV famotidine 12 mg/m(2) or ranitidine 60 mg/m(2) when gastric pH 1 hour with serial blood sampling following first dose. Twenty-four children randomized to either famotidine (n = 12) or ranitidine (n = 12). Sixteen out of twenty-four completed both PK and PD study arms (7/12 famotidine; 4.7 ± 3.4 years; 9/12 ranitidine; 6.6 ± 4.7 years; p = 0.38). Time to gastric pH 4.0 and total time pH above 4.0 similar with no difference in pH at 6 and 12 hours (p > 0.2). No difference between drugs in clearance, volume of distribution and half-life (p > 0.05). Ratio of AUC pH to AUC drug concentration 0-12 hours after first dose was significantly greater for famotidine (0.06849 ± 0.01460 SD) than ranitidine (0.02453 ± 0.01448; p < 0.001) demonstrating greater potency of famotidine. pH lowering efficacy of both drugs is similar. Greater potency of famotidine may offer clinical advantage due to lower drug exposure and less frequent dosing to achieve same pH lowering effect.

This study detailed the sequence of recurring inflammatory events associated with episodic allergen exposures of mice resulting in airway hyperreactivity, sustained inflammation, goblet cell hyperplasia, and fibrogenesis that characterize a lung with chronic asthma. Ovalbumin (OVA)-sensitized female Balb/c mice were exposed to saline-control or OVA aerosols for 1hr per day for episodes of 3 days every week for up to 8 weeks. Lung inflammation was assessed by inflammatory cell recoveries using bronchoalveolar lavages (BAL) and tissue collagenase dispersions. Cell accumulations were observed within airway submucosal and associated perivascular spaces using immunohistochemical and tinctorial staining methods. Airway responsiveness to methacholine aerosols were elevated after 2 weeks and further enhanced to a sustained level after the 4th and 8th weeks. Although by the 8th week, diminished OVA-induced accumulations of eosinophils, neutrophils and monocyte-macrophages were observed, suggesting diminished responsiveness, the BAL recovery of lymphocytes remained elevated. Airway but not perivascular lesions persisted with a proliferating cell population, epithelial goblet cell hyperplasia and evidence of enhanced collagen deposition. Examination of lung inflammatory cell content before the onset of the 1st, 2nd and 4th OVA exposure episodes demonstrated enhancements in residual BAL lymphocyte and BAL and tissue eosinophil recoveries with each exposure episode. Although tissue monocyte-macrophage numbers returned to baseline prior to each exposure episode, the greatest level of accumulation was observed after the 4th week. These results provide the basis for establishing the inflammatory and exposure criteria by which episodic environmental exposures to allergen might result in the development of a remodeled lung in asthma.

Highly branched, functionalized polymers have potential to act as efficient drug carrier systems. Dendrimers are ideal candidates among model hyperbranched polymers because of their well-defined structure and high density of functional groups. Using ibuprofen as a model drug, we studied the interaction between the drug and Polyamidoamine (PAMAM) dendrimers (generations 3 and 4 with --NH2 functionality) and Perstrop Polyol (generation 5, hyperbranched polyester with --OH functionality). FTIR and NMR studies suggest that ibuprofen predominantly forms a complex with PAMAM dendrimers because of the ionic interaction between the --NH2 end groups and the carboxyl group of ibuprofen. On an average, up to 78 molecules of ibuprofen could be incorporated into one molecule of PAMAM-G4-NH2 with 64 end groups. This complex is stable in deionized water and methanol. The in vitro release of ibuprofen from drug-dendrimer complex is appreciably slower compared to pure ibuprofen. The complexed drug enters A549 cells much more rapidly than pure drug suggesting that dendrimers may be able to carry the complexed drug inside cells efficiently. Hyperbranched Polyol (with 128 --OH end groups) appears to encapsulate approximately 24 drug molecules. Perhaps the lack of strong interactions between the --OH end groups and the drugs prevents complex formation.

Extracorporeal membrane oxygenation (ECMO) for the support of children outside the newborn period who have pulmonary failure is only recently becoming accepted. It is again being applied, after earlier failures, because well-trained teams and improved equipment and techniques are available following the success of neonatal ECMO. In addition, in Europe extracorporeal CO2 removal (ECCO2R) in adults has been more successful. The use of ECMO for pulmonary failure in children does not have fixed indications and has had considerably less success than neonatal ECMO. Patients who require inspired oxygen fractions of over 0.5 and positive end-expiratory pressures of over 6 cm H2O for more than 12 h after being treated for more than 48 h should be considered candidates, given the high mortality of children with ARDS (70%). Survival averages 50% to 60%. Circuits and patient management techniques are very similar to those for newborn ECMO, but patients usually require longer times on ECMO. There are many more options for cannulation for both venoarterial and venovenous techniques than in neonatal and cardiac ECMO. The improving results indicate that ECMO will play a part in treating children with pulmonary failure. Further studies will be required to determine which patients can benefit from ECMO as well as the exact application in each case.

Drug release from hyperbranched polymer-drug conjugates and the subsequent activity are influenced by the branching architecture and the linker. To gain an understanding of these effects, we used hyperbranched polyol and G4-OH polyamidoamine (PAMAM) dendrimer with methyl prednisolone (MP) as the model drug. The drug was conjugated to dendrimer or polyol using a glutaric acid (GA) or a succinic acid (SA) spacer. Drug payload was the highest with polyol, while in the case of dendrimer, a higher payload was achieved with the GA than the SA spacer. Cell uptake of the polymer conjugates in A549 lung epithelial cells was higher than that of the free drug, and the conjugates largely localized in the cytosol. The anti-inflammatory activity of polymer conjugated MP, as measured by inhibition of prostaglandin synthesis, was the highest for MP-SA-dendrimer conjugate, followed by MP-GA-polyol conjugate, and then MP-GA-dendrimer conjugate. This study suggests that the branching architecture and spacer influence the drug payload and pharmacological activity of a drug-nanopolymer conjugate, which may significantly influence the in vivo efficacy of these nanodevices. This has key implications in the eventual in vivo efficacy of these nanodevices.

Dendrimers are emerging as a relatively new class of polymeric biomaterials with applications in drug delivery, and imaging. Achieving a high drug payload in dendrimers, and understanding the therapeutic effect of the dendrimer-drug conjugates are receiving increasing attention. A high drug payload nanodevice was obtained by covalent conjugation of ibuprofen to a polyamidoamine (PAMAM-G4-OH) dendrimer. Using DCC as a coupling agent, 58 molecules of ibuprofen were covalently conjugated to one molecule of generation 4 PAMAM-OH dendrimer. Cellular entry of the fluoroisothiocynate (FITC)-labeled dendrimer-drug conjugate was evaluated in vitro by using human lung epithelial carcinoma A549 cells by flow cytometry, confocal microscopy and UV/Visible spectroscopy. The pharmacological activity of the dendrimer-ibuprofen conjugate was compared to pure ibuprofen at various time points by measuring the suppression of prostaglandin E2. Significant amounts of the conjugate entered the cells rapidly within 15 min. Suppression of prostaglandin was noted within 30 min for the dendrimer-drug conjugates versus 1 h for the free ibuprofen. The results suggest that dendrimers with high drug payload improve the drug's efficacy by enhanced cellular delivery, and may produce a rapid pharmacological response. These dendrimer-drug conjugates can potentially be further modified by attaching antibodies and ligands for targeted drug delivery.

To synthesize and evaluate hyperbranched polymer (HBP)-drug conjugates with high drug payload for enhanced cellular delivery.Polyol- and polyglycerol-ibuprofen conjugates with or without imaging agent fluorescein isothiocyanate (FITC) were synthesized using dicyclohexilcarbodiimide (DCC) as a coupling agent. Drug-polymer conjugates were characterized using 13C NMR, 1H NMR, and gel permeation chromatography (GPC). Stability of the drug-conjugates was studied using free drug release through a dialysis membrane. Cellular entry of FITC-labeled HBP conjugates was studied using fluorescence activated cell sorter (FACS), and cell supernatant was analyzed by UV-visible spectrophotometer. The intracellular localization of FITC-labeled conjugates in A549 lung epithelial cells was imaged using fluorescence microscopy. Anti-inflammatory activity of the HBP-ibuprofen conjugates was estimated in vitro by measuring the concentration of prostaglandin (PGE2) using an ELISA kit.The average number of ibuprofen molecules conjugated per molecule of HBP was estimated to be 50 for polyol and 53 for polyglycerol. The HBP-drug conjugates did not release the drug up to 72 h in methanol, indicating the presence of stable ester bonds. Both the polymer-drug conjugates entered the cells rapidly. The conjugates were localized in the cell cytosol as evidenced by fluorescence microscopy. Within 30 min, the HBP-drug conjugates showed rapid suppression of PGE2 synthesis, whereas free ibuprofen did not show any activity. At later times, the conjugates showed comparable activity.For the first time, we report HBP conjugates with a high drug payload. HBP-drug conjugates entered the cells rapidly and produced the desired pharmacological action. This study demonstrates that hyperbranched polyol and polyglycerol are promising nanovehicles for achieving enhanced cellular delivery of drugs.

Background In the evaluation of patients with acute asthma, pulsus paradoxus (PP) is an objective and noninvasive indicator of the severity of airway obstruction. However, in children PP may be difficult or impossible to measure. Indwelling arterial catheters facilitate the measurement of PP, but they are invasive and generally reserved for critically ill patients. Objective To determine the utility of the plethysmographic waveform (PP pleth ) of the pulse oximeter in measuring PP. Methods Patients from the pediatric intensive care unit, emergency department, and inpatient wards of a tertiary care pediatric hospital were eligible for the study. A total of 36 patients (mean age [SD], 11.2 [4.7] years) were enrolled in the study. Pulsus paradoxus was measured using the traditional auscultatory (PP ausc ) method with a sphygmomanometer. Pulsus paradoxus was then measured using a blood pressure cuff observing for the disappearance and reappearance of the (PP pleth ) on the pulse oximeter. Mean difference and 95% confidence intervals were calculated for each method. The 2 methods were also analyzed for correlation and agreement using the Pearson product moment correlation and a Bland and Altman plot. Results Patients with status asthmaticus had higher PP ausc and PP pleth readings compared with nonasthmatic patients. Pulsus paradoxus measured by plethysmography in patients with and without asthma was similar to PP ausc readings (mean difference, 0.6 mm Hg; 95% confidence interval, −0.6 to 2.1 mm Hg). Individual PP pleth readings showed significant correlation and agreement with PP ausc readings in patients both with and without asthma. Conclusion Measurement of PP using the pulse oximeter–pulse plethysmographic waveform offers a simple and noninvasive method for evaluating patients with airway obstruction.

Objective To compare the pharmacokinetics and metabolism of R (+)- and S (−)- ketorolac in children. Methods Children from 3 to 18 years old received 0.6 mg/kg racemic ketorolac intravenously. Serial blood samples were obtained for 12 hours, and urine was collected for 12 to 24 hours. Racemic ketorolac was measured in plasma, and racemic ketorolac, para-hydroxyketorolac, and ketorolac glucuronide were measured in urine by HPLC. S (−)- and R (+)-ketorolac were measured in plasma; S (−)- and R (+)-ketorolac and ketorolac glucuronide were measured in urine by chiral HPLC separation. Plasma pharmacokinetic parameters for racemic drug and both enantiomers were determined for each patient. Results Clearance of racemic ketorolac in children was approximately 2 times the clearance reported in adults. Clearance of the S (−) enantiomer was 4 times that of the R (+) enantiomer. Terminal half-life of S (−)-ketorolac was 40% that of the R (+) enantiomer, and the apparent volume of distribution of the S (−) enantiomer was greater than that of the R (+) form. Recovery of S (−)-ketorolac glucuronide was 2.3 times that of the R (+) enantiomer. Conclusion The higher clearance in children suggests that the weight-adjusted dose of ketorolac may have to be greater for children to achieve plasma concentrations comparable to those of adults. Because of the greater clearance and shorter half-life of S (−)-ketorolac, pharmacokinetic predictions based on racemic assays may overestimate the duration of pharmacologic effect. Enantiomeric pharmacokinetic differences are best explained by stereoselective plasma protein binding. Selective glucuronidation of the S (−) enantiomer suggests that stereoselective metabolism may also be a contributing factor. Clinical Pharmacology & Therapeutics (1999) 65, 382–388; doi

Ketorolac (KT) is a parenteral nonsteroidal anti-inflammatory analgesic used for the treatment of moderate to severe pain. We studied the efficacy and safety of intravenous (IV) KT, compared to IV morphine (MS) in critically-ill children.

Ketorolac (KT) is administered as a racemic mixture although cyclooxygenase inhibitory activity resides with the (-S) stereoisomer. Little is known about KT stereo-specific pharmacokinetics. We studied plasma pharmacokinetics of(+R) and (-S) KT in 8 children (median age 11.8 yrs) following a 0.6 mg/kg IV dose of racemic KT. Twelve timed plasma samples were collected over 720 minutes after the dose. (+R)-KT and (-S)-KT were measured by HPLC using a CHIRACEL OJ-R column. Kinetic values were estimated from non-linear iterative fit of the the plasma concentrations to a bi-exponential or tri-exponential equation with 10 minutes infusion function. Significant differences were observed between the two enantiomers: Cmax was higher, AUC greater, t1/2elim longer, and Cl less for (+R)-KT. There was no difference between the enatiomers in Vd or t1/2dist. Table

In an effort to delineate the clinical characteristics of respiratory syncytial virus (RSV) infection in the compromised host, we compared children with bronchopulmonary dysplasia (BPD), congenital heart disease (CHD), premature birth, failure to thrive, and gastroesophageal reflux to previously healthy children. During a four-year period, 262 patients were admitted to the hospital with RSV infection diagnosed by a rapid RSV antigen detection test. Children with BPD or CHD had more hospital days and supplemental oxygen days than the previously healthy group (P less than 0.05). Patients with BPD also had more ICU days, ventilator days, and NPO days, as well as a higher physiologic stability index and therapeutic intervention score than the previously healthy group (P less than 0.05). Premature infants were more likely to present with apnea from RSV (P less than 0.001). Patients with underlying illness tended to be older, although significant difference was demonstrated only for the BPD group (7.0 +/- 5.3 vs. 3.5 +/- 3.3, P less than 0.05). Patients with BPD and CHD had more nosocomial infections than the previously healthy group (P less than 0.0001) and death occurred only in patients with underlying illness. We conclude that previously compromised patients are at risk for more severe and prolonged RSV disease. Earlier diagnosis and therapeutic intervention may be necessary in such patients to improve outcome.