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Meyer A.D.,University of Texas Health Science Center at San Antonio | Wiles A.A.,Childrens National Research Institute | Rivera O.,Childrens National Medical Center | Wong E.C.,Center for Clinical and Community Research | And 3 more authors.
Pediatric Critical Care Medicine | Year: 2012

OBJECTIVE:: A state-of-the-art centrifugal pump combined with hollow-fiber oxygenator for extracorporeal membrane oxygenation has potential advantages such as smaller priming volumes and decreased potential to cause tubing rupture as compared with the traditional roller head/silicone membrane systems. Adoption of these state-of-the-art systems has been slow in neonates as a result of past evidence of severe hemolysis that may lead to renal failure and increased mortality. Extracorporeal systems have also been linked to platelet dysfunction, a contributing factor toward intracranial hemorrhage, a leading cause of infant morbidity. Little data exist comparing the centrifugal systems with the roller systems in terms of hemolysis and platelet aggregation at low flow rates commonly used in neonatal extracorporeal membrane oxygenation. DESIGN:: Prospective, comparative laboratory study. SETTING:: University research laboratory. SUBJECTS:: Centrifugal pump, roller pump, hollow-fiber oxygenator, and silicone membrane oxygenator. INTERVENTIONS:: Comparative study using two pumps, the centrifugal Jostra Rotaflow (Maquet, Wayne, NJ) and the roller-head (Jostra, Maquet, Wayne, NJ), and two oxygenators, polymethlypentene Quadrox-D (Maquet) and silicone membrane (Medtronic, Minneapolis, MN). Five test runs of four circuit combinations were examined for hemolysis and platelet aggregation during 6 hrs of continuous use in a simulated in vitro extracorporeal membrane oxygenation circuit circulating whole swine blood at 300 mL/min. MEASUREMENTS AND MAIN RESULTS:: Hemolysis was assessed by spectrophometric measurement of plasma-free hemoglobin. Platelet aggregation was evaluated using monoclonal CD61 antibody fluorescent flow cytometry profiles. All of the extracorporeal membrane oxygenation systems created plasma-free hemoglobin at a similar rate compared with static blood control. There was no difference in the mean normalized index of hemolysis of the centrifugal/hollow-fiber oxygenator system as compared with the roller-head/silicone membrane systems (0.0032 g/100 L vs. 0.0058 g/100 L, p .7). None of the extracorporeal membrane oxygenation systems had a significant increase in platelet aggregation above baseline. CONCLUSIONS:: In a low-flow neonatal environment, a state-of-the-art centrifugal pump combined with new fiber-type oxygenators appear to be safe in regard to hemolysis and platelet aggregation. Copyright © 2012 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies. Source

Schwartz L.A.,Childrens Hospital of Philadelphia | Schwartz L.A.,University of Pennsylvania | Tuchman L.K.,Center for Clinical and Community Research | Tuchman L.K.,George Washington University | And 3 more authors.
Child: Care, Health and Development | Year: 2011

Background Policy and research related to transition to adult care for adolescents and young adults (AYAs) has focused primarily on patient age, disease skills and knowledge. Objective In an effort to broaden conceptualization of transition and move beyond isolated patient variables, a new social-ecological model of AYA readiness for transition (SMART) was developed. Methods SMART development was informed by related theories, literature, expert opinion and pilot data collection using a questionnaire developed to assess provider report of SMART components with 100 consecutive patients in a childhood cancer survivorship clinic. Results The literature, expert opinion and pilot data collection support the relevance of SMART components and a social-ecological conceptualization of transition. Provider report revealed that many components, representing more than age, disease knowledge and skills, related to provider plans for transferring patients. Conclusions SMART consists of inter-related constructs of patients, parents and providers with emphasis on variables amenable to intervention. Results support SMART's broadened conceptualization of transition readiness and need for assessment of multiple stakeholders' perspectives of patient transition readiness. A companion measure of SMART, which will be able to be completed by patients, parents and providers, will be developed to target areas of intervention to facilitate optimal transition readiness. Similar research programmes to establish evidence-based transition measures and interventions are needed. © 2011 Blackwell Publishing Ltd. Source

Pati S.,Childrens Hospital of Philadelphia | Pati S.,University of Pennsylvania | Feemster K.A.,University of Pennsylvania | Feemster K.A.,Childrens Hospital of Philadelphia | And 5 more authors.
Maternal and Child Health Journal | Year: 2011

To determine if maternal health literacy influences early infant immunization status. Longitudinal prospective cohort study of 506 Medicaid-eligible motherinfant dyads. Immunization status at age 3 and 7 months was assessed in relation to maternal health literacy measured at birth using the Test of Functional Health Literacy in Adults (short version). Multivariable logistic regression quantified the effect of maternal health literacy on immunization status adjusting for the relevant covariates. The cohort consists of primarily African-American (87%), single (87%) mothers (mean age 23.4 years). Health literacy was inadequate or marginal among 24% of mothers. Immunizations were upto- date among 73% of infants at age 3 months and 43% at 7 months. Maternal health literacy was not significantly associated with immunization status at either 3 or 7 months. In multivariable analysis, compared to infants who had delayed immunizations at 3 months, infants with up-to-date immunizations at 3 months were 11.3 times (95%CI 6.0- 21.3) more likely to be up-to-date at 7 months. The only strong predictors of up-to-date immunization status at 3 months were maternal education (high school graduate or beyond) and attending a hospital-affiliated clinic. Though maternal health literacy is not associated with immunization status in this cohort, later immunization status is most strongly predicted by immunization status at 3 months. These results further support the importance of intervening from an early age to ensure that infants are fully protected against vaccine preventable diseases. © Springer Science+Business Media, LLC 2010. Source

Yu B.,Johns Hopkins University | Zhao X.,University of Hong Kong | Yang C.,Center for Clinical and Community Research | Crane J.,Johns Hopkins University | And 4 more authors.
Journal of Bone and Mineral Research | Year: 2012

Parathyroid hormone (PTH) stimulates bone remodeling and induces differentiation of bone marrow mesenchymal stromal/stem cells (MSCs) by orchestrating activities of local factors such as bone morphogenetic proteins (BMPs). The activity and specificity of different BMP ligands are controlled by various extracellular antagonists that prevent binding of BMPs to their receptors. Low-density lipoprotein receptor-related protein 6 (LRP6) has been shown to interact with both the PTH and BMP extracellular signaling pathways by forming a complex with parathyroid hormone 1 receptor (PTH1R) and sharing common antagonists with BMPs. We hypothesized that PTH-enhanced differentiation of MSCs into the osteoblast lineage through enhancement of BMP signaling occurs by modifying the extracellular antagonist network via LRP6. In vitro studies using multiple cell lines, including Sca-1+CD45-CD11b -MSCs, showed that a single injection of PTH enhanced phosphorylation of Smad1 and could also antagonize the inhibitory effect of noggin. PTH treatment induced endocytosis of a PTH1R/LRP6 complex and resulted in enhancement of phosphorylation of Smad1 that was abrogated by deletion of PTH1R, β-arrestin, or chlorpromazine. Deletion of LRP6 alone led to enhancement of pSmad1 levels that could not be further increased with PTH treatment. Finally, knockdown of LRP6 increased the exposure of endogenous cell-surface BMP receptor type II (BMPRII) significantly in C2C12 cells, and PTH treatment significantly enhanced cell-surface binding of 125I-BMP2 in a dose- and time-dependent manner, implying that LRP6 organizes an extracellular network of BMP antagonists that prevent access of BMPs to BMP receptors. In vivo studies in C57BL/6J mice and of transplanted green fluorescent protein (GFP)-labeled Sca-1+CD45-CD11b-MSCs into the bone marrow cavity of Rag2-/- immunodeficient mice showed that PTH enhanced phosphorylation of Smad1 and increased commitment of MSCs to osteoblast lineage, respectively. These data demonstrate that PTH enhancement of MSC differentiation to the osteoblast lineage occurs through a PTH- and LRP6-dependent pathway by endocytosis of the PTH1R/LRp6 complex, allowing enhancement of BMP signaling. © 2012 American Society for Bone and Mineral Research. Source

Tuchman L.K.,Center for Clinical and Community Research | Schwartz L.A.,Childrens Hospital of Philadelphia | Sawicki G.S.,Childrens Hospital Boston | Britto M.T.,Cincinnati Childrens Hospital Medical Center
Pediatrics | Year: 2010

Transition of young adults with cystic fibrosis (CF) from pediatric to adult medical care is an important priority, because many patients are living well into their fourth decade, and by 2010 more than half of all people living with CF will be older than 18 years. Transition to adulthood, a developmental process of skill-building in self-management supported by the health system, is important for the successful transfer to adult CF care. The US Cystic Fibrosis Foundation has been proactive in preparing for increasing numbers of young adults in need of specialized adult-oriented care by creating specialized clinical fellowships for physician providers and mandating establishment of adult CF programs. Despite these initiatives, how to best facilitate transition and to define and measure successful outcomes after transfer to adult care remains unclear. Many adults with CF continue to receive care in the pediatric setting, whereas others transfer before being developmentally prepared. In this state-of-the-art review we provide context for the scope of the challenges associated with designing and evaluating health care transition for adolescents and young adults with CF and implications for all youth with special health care needs. Copyright © 2010 by the American Academy of Pediatrics. Source

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