bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of the Centaur TnI-Ultra Assay for Detection of Myocardial Infarction and Adverse Events in Patients Presenting With Symptoms Suggestive of Acute Coronary Syndrome
Authors: Apple Fred S , Smith Stephen W , Pearce Lesly A , Ler Ranka , Murakami MaryAnn M
Published: February 2008

Background: We determined the diagnostic accuracy of the Advia Centaur TnI-Ultra assay for detecting myocardial infarction (MI) and assessing risk of adverse events in patients presenting with ischemic symptoms suggestive of acute coronary syndrome.

Methods: We measured cardiac troponin I (cTnI) on admission and 6–24 h after admission (follow-up) in plasma specimens from 371 consecutive patients. The end point was the first of cardiac event or death within 60 days. We estimated survival curves using the Kaplan-Meier method and compared groups with the log rank statistic.

Results: MI was established in 49 patients (13%). Clinical sensitivities and specificities for MI based on the 99th percentile (0.04 μg/L) were 74% and 84%, respectively, on admission and 94% and 81% at follow-up. ROC curves showed significantly higher accuracy for MI in the follow-up specimen compared with admission (P = 0.001). Overall there were 2 cardiac deaths, 1 noncardiac death, 49 MIs, 7 coronary artery bypass grafts, and 36 percutaneous coronary interventions in 59 patients during follow-up. The event rate in those with cTnI <0.006 μg/L was significantly lower than in groups with cTnI 0.006–0.04 μg/L, >0.04–0.10 μg/L, or >0.10 μg/L (2.8% vs 11.1%, 24.1%, 55.1%, respectively; P <0.0001). Relative risks for the increasing cTnI cutoff groups were 3.9 (95% CI 1.2–13), 8.9 (2.4–34), and 25 (7.3–82) after adjustment for age, diabetes, history of hypertension, previous MI, and estimated glomerular filtration rate.

Conclusions: The TnI-Ultra assay is a sensitive, early diagnostic biomarker for MI and an independent predictor of adverse events at any measurable cTnI in patients with symptoms of acute coronary syndrome.
Reviews
Authors: Stahl Matt , Cordova Nathaniel I , Thornton Brian , Clarke Debra M , Marshall P. David , Pecora Norma
Published: February 2008

Conglomerate Rock: The Music Industry's Quest to Divide Music and Conquer Wallets, David J. Park (2007) Lanham, MD: Lexington Books, 160 pp., ISBN: 0739115006, 60.00 (hbk)

Troubled Pasts: News and the Collective Memory of Social Unrest, Jill A. Edy (2006)
Philadelphia: Temple University Press, ISBN: 1592134963, 71.50 (hbk); ISBN: 1592134971, 23.95 (pbk)

Journalists and the Public: Newsroom Culture, Letters to the Editor, and Democracy, Karin Wahl-Jorgensen (2007) Cresskill, NJ: Hampton Press, 165 pp., 47.50 (pbk), ISBN 9781572737372

Canadian
Television Today, Bart Beaty and Rebecca Sullivan (2006) Calgary: University of Calgary Press, 168 pp., ISBN 9781552382226 (pbk), 24.95

Framing Celebrity: New Directions in Celebrity Culture, Su Holmes and Sean Redmond (eds.) (2006) London: Routledge, 384 pp., ISBN:
0415377099, 125.00 (hbk); ISBN: 0415377102, 33.95 (pbk)

Kids Rule!: Nickelodeon and Consumer Citizenship, Sarah Banet-Weiser (2007) Durham: Duke University Press, ISBN: 9780822339762, 79.95 (cloth); ISBN: 9780822339939, 22.95 (pbk)
Globalisation, communications and political action: Special issue introduction
Authors: Youngs Gillian , Allison Juliann Emmons
Published: February 2008

This article introduces the special issue and argues that the contributions in it lead us to think more deeply about the need for endogenous rather than exogenous approaches to information and communications technologies (ICTs) in our analysis of globalisation, communications and political
action. The argument covers three areas: globalisation virtual and material processes; communications as integral to politics; political action and new virtual forms.
Improving the prospects for sustainable ICT projects in the developing world
Authors: Hosman Laura , Fife Elizabeth
Published: February 2008

Projects that bring information and communications technology (ICT) to the developing world and especially to rural areas have the potential to empower the disenfranchised, foster economic opportunity, and narrow the digital divide that threatens to widen global disparity between the
haves and the have-nots. However, given the remarkable growth of such undertakings around the world, there has been little corresponding effort made to address the vital issues of long-term project sustainability and the diverse motivations and incentives facing the actors involved. As a result,
these projects continue to be implemented sporadically and in a piecemeal fashion, which in turn hinders our ability to define success and recommend best practices for implementing and/or scaling them. Through an analysis of publicprivate partnerships (PPPs), the prevailing vehicle for project
implementation today, the article addresses the issue of sustainability through partnerships, and also asserts that developing world technology recipients must be considered as stakeholders, as they hold the key to project sustainability. Following an overview of both theory and the current
state of ICT-related development projects, the article provides a case study of a Sri Lankan-based pilot project involving multiple stakeholders. This case reveals important success factors that can be applied to future developing world ICT projects.
Hypothyroxinemia and Prematurity
Authors: Forghani Nikta , Aye Tandy
Published: February 2008

The growing fetus relies on adequate thyroid hormone concentrations for normal development, which is dependent on maternal transplacental thyroid hormone passage and the appropriate development of the fetal hypothalamic-pituitary-thyroid axis. Untreated congenital hypothyroidism can result in severe neurodevelopmental disabilities, including mental retardation, auditory dysfunction, and spastic diplegia. Most outcomes data also suggest that up to 10% of infants treated early in the era of newborn screening still have long-term disabilities, although they are minor. Preterm infants have lower serum concentrations of thyroid hormones compared with their term counterparts early in postnatal life, and there has been a concern that this transient hypothyroxinemia could be partially responsible for the neurodevelopmental impairment associated with prematurity. Therefore, a number of investigators have examined this relationship and the potential use of thyroid hormone in preterm infants to improve neurodevelopmental outcomes. This article reviews this literature and discusses possible directions for the future.
Ambiguous Genitalia in the Newborn
Authors: Chi Carolyn , Lee Henry Chong , Neely E. Kirk
Published: February 2008

Efficient and accurate evaluation of the newborn who has ambiguous genitalia is required to provide appropriate medical therapy and assuage parental anxiety. Genital ambiguity usually is due to virilization of genetic females or undervirilization of genetic males who have normal gonads. Congenital adrenal hyperplasia is the most common condition leading to inappropriate virilization in females. Defects in testosterone production, metabolism, or peripheral action can lead to ambiguous genitalia in males. In any condition involving ambiguous genitalia or question of sex assignment, a karyotype should be obtained within 24 hours of delivery. Parents should be apprised of the situation in a professional manner with the appropriate level of detail; sex assignment should be withheld until sufficient data are gathered to make an accurate diagnosis. Families can be counseled with the latest available information and resources to make the best decisions for their individual situations.
Environmental Factors and Puberty Timing: Expert Panel Research Needs
Authors: Buck Louis Germaine M. , Gray L. Earl , Marcus Michele , Ojeda Sergio R. , Pescovitz Ora H. , Witchel Selma Feldman , Sippell Wolfgang , Abbott David H. , Soto Ana , Tyl Rochelle W. , Bourguignon Jean-Pierre , Skakkebaek Niels E. , Swan Shanna H. , Golub Mari S. , Wabitsch Martin , Toppari Jorma , Euling Susan Y.
Published: February 2008

Serono Symposia International convened an expert panel to review the impact of environmental influences on the regulation of pubertal onset and progression while identifying critical data gaps and future research priorities. An expert panel reviewed the literature on endocrine-disrupting chemicals, body size, and puberty. The panel concluded that available experimental animal and human data support a possible role of endocrine-disrupting chemicals and body size in relation to alterations in pubertal onset and progression in boys and girls. Critical data gaps prioritized for future research initiatives include (1) etiologic research that focus on environmentally relevant levels of endocrine-disrupting chemicals and body size in relation to normal puberty as well as its variants, (2) exposure assessment of relevant endocrine-disrupting chemicals during critical windows of human development, and (3) basic research to identify the primary signal(s) for the onset of gonadotropin-releasing hormone–dependent/central puberty and gonadotropin-releasing hormone–independent/peripheral puberty. Prospective studies of couples who are planning pregnancies or pregnant women are needed to capture the continuum of exposures at critical windows while assessing a spectrum of pubertal markers as outcomes. Coupled with comparative species studies, such research may provide insight regarding the causal ordering of events that underlie pubertal onset and progression and their role in the pathway of adult-onset disease.
Age of Alcohol Use Initiation, Suicidal Behavior, and Peer and Dating Violence Victimization and Perpetration Among High-Risk, Seventh-Grade Adolescents
Authors: Swahn Monica H. , Bossarte Robert M. , Sullivent Ernest E.
Published: February 2008

OBJECTIVE. We examined the cross-sectional associations between reports of an early age of alcohol use initiation and suicidal ideation, suicide attempts, and peer and dating violence victimization and perpetration among high-risk adolescents.

METHOD. Data were obtained from the Youth Violence Survey conducted in 2004 and administered to all public school students enrolled in grades 7, 9, and 11/12 (N = 4131) in a high-risk school district in the United States. Our analyses were limited to seventh-grade students who either began drinking before the age of 13 or were nondrinkers, with complete information on all covariates (n = 856). Cross-sectional logistic and multinomial logistic regression analyses were conducted to determine the associations between early alcohol use and each of the 6 outcome behaviors (dating violence victimization and perpetration, peer violence victimization and perpetration, suicidal ideation, and suicide attempts) while controlling for demographic characteristics and other potential confounders (ie, heavy episodic drinking, substance use, peer drinking, depression, impulsivity, peer delinquency, and parental monitoring).

RESULTS. In our study, 35% of students reported alcohol use initiation before 13 years of age (preteen alcohol use initiators). Students who reported preteen alcohol use initiation reported involvement in significantly more types of violent behaviors (mean: 2.8 behaviors), compared with nondrinkers (mean: 1.8 behaviors). Preteen alcohol use initiation was associated significantly with suicide attempts, relative to nondrinkers, controlling for demographic characteristics and all other potential confounders.

CONCLUSIONS. Early alcohol use is an important risk factor for involvement in violent behaviors and suicide attempts among youths. Increased efforts to delay and to reduce early alcohol use among youths are needed and may reduce both violence and suicide attempts.
Barriers to Palliative Care for Children: Perceptions of Pediatric Health Care Providers
Authors: Davies Betty , Sehring Sally A. , Partridge J. Colin , Cooper Bruce A. , Hughes Anne , Philp Julie C. , Amidi-Nouri Aara , Kramer Robin F.
Published: February 2008

OBJECTIVE. The goal was to explore barriers to palliative care experienced by pediatric health care providers caring for seriously ill children.

METHODS. This study explored pediatric provider perceptions of end-of-life care in an academic children's hospital, with the goal of describing perceived barriers to end-of-life care for children and their families. The report focuses on the responses of nurses (n = 117) and physicians (n = 81).

RESULTS. Approximately one half of the respondents reported 4 of 26 barriers listed in the study questionnaire as frequently or almost always occurring, that is, uncertain prognosis (55%), family not ready to acknowledge incurable condition (51%), language barriers (47%), and time constraints (47%). Approximately one third of respondents cited another 8 barriers frequently arising from problems with communication and from insufficient education in pain and palliative care. Fourteen barriers were perceived by >75% of staff members as occasionally or never interfering with pediatric end-of-life care. Comparisons between physicians and nurses and between ICU and non-ICU staff members revealed several significant differences between these groups.

CONCLUSIONS. Perceived barriers to pediatric end-of-life care differed from those impeding adult end-of-life care. The most-commonly perceived factors that interfered with optimal pediatric end-of-life care involved uncertainties in prognosis and discrepancies in treatment goals between staff members and family members, followed by barriers to communication. Improved staff education in communication skills and palliative care for children may help overcome some of these obstacles, but pediatric providers must realize that uncertainty may be unavoidable and inherent in the care of seriously ill children. An uncertain prognosis should be a signal to initiate, rather than to delay, palliative care.
Experiences of Parents Who Have Children With Chronic Kidney Disease: A Systematic Review of Qualitative Studies
Authors: Tong Allison , Lowe Alison , Sainsbury Peter , Craig Jonathan C.
Published: February 2008

OBJECTIVE. The objective of this study was to describe the experiences of parents who have children with chronic kidney disease.

METHODS. We conducted a systematic review and meta-ethnography of studies that had used in-depth interviews or focus groups to explore experiences of parents with children who have chronic kidney disease (predialysis, hemodialysis, peritoneal dialysis, or after kidney transplantation). We searched 5 electronic databases (through to August 2005), Medline, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, and Sociofile/Sociological Abstract, and reference lists of relevant articles.

RESULTS. Sixteen articles that reported the experiences of parents of 358 children with chronic kidney disease were included. Ten themes emerged, which we grouped into 3 interrelated clusters: intrapersonal (living with constant uncertainty, stress, and maintaining vigilance despite experiencing fatigue), interpersonal (medicalization of the parental role, dependence on and conflict with staff, and disrupted peer relationships), and external issues (management of the medical regimen, pursuit of information, organizing transportation, accommodation and finances, adhering to the child's liquid and diet restrictions, and balancing medical care with domestic responsibilities).

CONCLUSIONS. In addition to “normal” parental roles, being a parent of a child with chronic kidney disease demands a high-level health care provider, problem solving, information seeking, and financial and practical skills at a time when the capacity to cope is threatened by physical tiredness, uncertainty, and disruption to peer support within and outside the family structure. Parents of children with chronic kidney disease need multidisciplinary care, which may lead to improved outcomes for their children.
Population-Based Assessments of Ophthalmologic and Audiologic Follow-up in Children With Very Low Birth Weight Enrolled in Medicaid: A Quality-of-Care Study
Authors: Wang C. Jason , Elliott Marc N. , McGlynn Elizabeth A. , Brook Robert H. , Schuster Mark A.
Published: February 2008

OBJECTIVE. The purpose of our work was to determine whether children with very low birth weight (<1500 g) who are at high risk for vision and hearing problems and enrolled in Medicaid receive recommended follow-up vision and hearing services and to examine predictors of services.

PATIENTS AND METHODS. We conducted a retrospective analysis of 2182 children born in South Carolina from 1996 to 1998 with birth weights of 401 to 1499 g, gestations of ≥24 weeks, and survival of ≥90 days of life. Receipt of services for Medicaid-enrolled children was assessed by using a linked data set that included files from vital records, death certificates, Medicaid, Chronic Rehabilitative Services, and the Early Intervention Program. We assessed the receipt of hearing rehabilitation by 6 months of age for children with nonconductive hearing loss and routine ophthalmologic examination between ages of 1 and 2 years for all children with very low birth weight. Multivariate logistic regression was restricted to ophthalmologic examinations because of sample size.

RESULTS. Among children with very low birth weight with nonconductive hearing loss, 20% received hearing rehabilitation by 6 months of age. Twenty-three percent of children with very low birth weight received an ophthalmologic examination between the ages of 1 and 2 years. Limiting our analysis to children <1000 g or extending the measurement period to 7 months (hearing) and age 3 years (vision) did not substantially increase the percentage of children receiving the services. The receipt of an ophthalmologic examination was associated positively with Medicaid enrollment by the time of hospital discharge and birth in a level-3 hospital and negatively associated with higher birth weight, an Apgar score of ≥7, and black maternal race. Among children born at <1000 g, all of whom were eligible for the Early Intervention Program, the receipt of an ophthalmologic examination was positively associated with program enrollment.

CONCLUSIONS. There is a shortfall in the provision of critical services for children with very low birth weight. These findings reinforce the Institute of Medicine's concerns regarding inadequate outcome data and health care services for preterm infants and support the importance of enrollment in the Early Intervention Program for children with very low birth weight.
Quality of Life of Formerly Preterm and Very Low Birth Weight Infants From Preschool Age to Adulthood: A Systematic Review
Authors: Zwicker Jill Glennis , Harris Susan Richardson
Published: February 2008

OBJECTIVE. The goal of this systematic review was to synthesize studies that examined the health-related quality of life of preschool- and school-aged children, adolescents, and young adults who were born preterm and/or at very low birth weight.

METHODS. We searched 7 databases up to September 2006 (Medline, PubMed, Embase, EBM Reviews, Cumulative Index of Nursing and Allied Health Literature, PsycINFO, and the Educational Resource Information Center) as well as gray literature sources. We independently screened studies and included them only if a quality-of-life outcome measure was used and findings compared preterm, very low birth weight, or extremely low birth weight infants with term or normal birth weight peers. We independently assessed the methodologic quality of each study by using criteria adapted from the Centre for Reviews and Dissemination.

RESULTS. Fifteen cohort or cross-sectional studies met the review criteria. In 6 studies of preschool-aged children, differences were found between study and control groups, suggesting that many preschool children born preterm or at very low birth weight perform more poorly than their peers in physical, emotional, and/or social functioning. Extremely low birth weight school-aged children had lower health utility scores compared with their peers, and similar results were found for adolescents. Parents of preterm and very low birth weight teens noted significantly poorer performance in their child's global health, behavior, and physical functioning, whereas the teenagers themselves did not. In young adulthood, differences in physical functioning remained, but subjective quality of life was similar to normal birth weight peers.

CONCLUSIONS. The effects of preterm birth/very low birth weight on health-related quality of life seem to diminish over time, which possibly reflects issues related to a child's report versus a parent-proxy report, differing definitions of health-related quality of life, and adaptation of individuals over time, versus true change in health-related quality of life.
Many Pediatric Residents Seek and Obtain Part-time Positions
Authors: Cull William L. , Caspary Gretchen L. , Olson Lynn M.
Published: February 2008

OBJECTIVE. The goal was to monitor the number of pediatric residents seeking part-time employment after graduation and to examine the difficulty of their job searches, compared with residents seeking full-time employment.

METHODS. As part of the American Academy of Pediatrics Graduating Resident Survey, national random samples of 500 graduating, categorical pediatrics residents were surveyed from 2003 through 2005, between May and August of each year. Responses were pooled to examine resident interest in and experience with part-time employment. Totals of 308 (62%), 307 (61%), and 281 (56%) residents completed the survey in 2003, 2004, and 2005, respectively. Analyses focused on residents who applied for nonfellowship jobs.

RESULTS. A total of 51% of residents applied for nonfellowship jobs. Of those who applied for such jobs, 38% reported that they applied for part-time positions and 21% actually accepted part-time positions. Residents who applied for part-time positions were more likely to report moderate or considerable job search difficulty (part-time: 36%; full-time: 25%). The average starting salary for residents who accepted part-time jobs was almost $34000 less than that for residents working full-time (part-time: $71615; full-time: $105598). Residents who accepted part-time positions expected to work 15 hours less per week in practice (38 vs 23 hours) and were more likely to accept a position in the same city/area as their residency (part-time: 60%; full-time: 47%).

CONCLUSIONS. Approximately 4 of 10 pediatric residents seek part-time employment after graduation, and 2 of 10 accept part-time positions. Strong interest in part-time positions is likely to continue, and this important trend has implications for the pediatric workforce.
Prematurely Born Children Demonstrate White Matter Microstructural Differences at 12 Years of Age, Relative to Term Control Subjects: An Investigation of Group and Gender Effects
Authors: Constable R. Todd , Ment Laura R. , Vohr Betty R. , Kesler Shelli R. , Fulbright Robert K. , Lacadie Cheryl , Delancy Susan , Katz Karol H. , Schneider Karen C. , Schafer Robin J. , Makuch Robert W. , Reiss Allan R.
Published: February 2008

OBJECTIVE. The goal was to use diffusion tensor imaging to test the hypothesis that prematurely born children demonstrate long-term, white matter, microstructural differences, relative to term control subjects.

METHODS. Twenty-nine preterm subjects (birth weight: 600–1250 g) without neonatal brain injury and 22 matched, term, control subjects were evaluated at 12 years of age with MRI studies, including diffusion tensor imaging and volumetric imaging; voxel-based morphometric strategies were used to corroborate regional diffusion tensor imaging results. Subjects also underwent neurodevelopmental assessments.

RESULTS. Neurodevelopmental assessments showed significant differences in full-scale, verbal, and performance IQ and Developmental Test of Visual Motor Integration scores between the preterm and term control subjects. Diffusion tensor imaging studies demonstrated widespread decreases in fractional anisotropy (a measure of fiber tract organization) in the preterm children, compared with the control subjects. Regions included both intrahemispheric association fibers subserving language skills, namely, the right inferior frontooccipital fasciculus and anterior portions of the uncinate fasciculi bilaterally, and the deep white matter regions to which they project, as well as the splenium of the corpus callosum. These changes in fractional anisotropy occurred in subjects with significant differences in frontal, temporal, parietal, and deep white matter volumes. Fractional anisotropy values in the left anterior uncinate correlated with verbal IQ, full-scale IQ, and Peabody Picture Vocabulary Test-Revised scores for preterm male subjects. In addition, preterm male subjects were found to have the lowest values for fractional anisotropy in the right anterior uncinate fasciculus, and fractional anisotropy values in that region correlated with both verbal IQ and Peabody Picture Vocabulary Test-Revised scores for the preterm groups; these findings were supported by changes identified with voxel-based morphometric analyses.

CONCLUSIONS. Compared with term control subjects, prematurely born children with no neonatal ultrasound evidence of white matter injury manifest changes in neural connectivity at 12 years of age.
Influence of Multiple Social Risks on Children's Health
Authors: Larson Kandyce , Russ Shirley A. , Crall James J. , Halfon Neal
Published: February 2008

OBJECTIVE. Social risk factors such as growing up in poverty, racial/ethnic minority status, and maternal depression have been associated with poorer health outcomes for children. This study examined the strength of association of 8 social risk factors, both individually and as part of a cumulative social risk index, on parent-reported child health status.

METHODS. We performed an analysis of cross-sectional data from the 2003 National Survey of Children's Health, a telephone survey of 102353 parents of children aged 0 to 17 years. In bivariate and multivariate logistic regression models, 8 social risk factors were tested as independent predictors of 4 parent-reported child health outcomes: global health status, dental health, socioemotional health, and overweight. These risk factors were combined into a categorical “social risk index” ranging from low risk (0 risk factors) to very high risk (≥6 risk factors), and risk gradients were examined using linear polynomial testing and multivariate logistic regression.

RESULTS. The percentage of children in poorer health increased with the number of social risk factors across all health outcomes. More than half of children had ≥2 risk factors, and 24% had ≥4. Low maternal mental health, black or Hispanic race/ethnicity, <200% of the federal poverty level, low household education, unsafe neighborhoods, and lack of health insurance increased the odds for less than very good child health in adjusted models.

CONCLUSIONS. Multiple social risk factors have a cumulative effect on parent-reported child health status across physical and socioemotional domains, demonstrating a very strong risk gradient effect. These findings emphasize the importance of addressing multiple levels of social risk to achieve improvements in child health.
Risk Factors for Severe Respiratory Syncytial Virus Disease in Children With Cancer: The Importance of Lymphopenia and Young Age
Authors: El Saleeby Chadi M. , Somes Grant W. , DeVincenzo John P. , Gaur Aditya H.
Published: February 2008

OBJECTIVE. We sought to determine the epidemiologic features of respiratory syncytial virus infection in immunocompromised pediatric patients and to identify the risk factors for severe disease.

METHODS. We designed a retrospective study examining the experience with respiratory syncytial virus infection in pediatric patients with underlying malignancies and hematopoietic stem cell transplant recipients seen between 1997 and 2005. Clinical and laboratory data were extracted from patient records, and independent predictors of disease severity were investigated.

RESULTS. Fifty-eight patients met the study criteria. Twenty-three patients (40%) had underlying diagnoses of acute lymphoblastic leukemia, 11 (19%) had solid tumors, and 24 (41%) were hematopoietic stem cell transplant recipients, had acute myeloid leukemia, or had severe combined immunodeficiency syndrome. Seventeen patients (29%) were <2 years of age. Overall, 16 patients (28%) developed lower respiratory tract infections. The frequency of lower respiratory tract infections was highest in patients with hematopoietic stem cell transplants, acute myeloid leukemia, or severe combined immunodeficiency syndrome (42%). Independent predictors of lower respiratory tract infections were profound lymphopenia, with absolute lymphocyte counts of <100 cells per mm3, and age of ≤2 years. Of all patients with lower respiratory tract infections, 31% died as a result of respiratory syncytial virus infection. The overall mortality rate was low (5 of 58 patients; 8.6%). All deaths occurred in patients with lower respiratory tract infections who were before or after hematopoietic stem cell transplants or were <2 years of age and receiving treatment for acute myeloid leukemia. Neutropenia was not a predictor of respiratory syncytial virus lower respiratory tract infection or death.

CONCLUSIONS. This study identified profound lymphopenia and young age as independent predictors of respiratory syncytial virus-related lower respiratory tract infections in immunocompromised children. No association between neutropenia and respiratory syncytial virus-related morbidity or death was found. These findings can guide interventions for respiratory syncytial virus infection in high risk hosts.
Neurodevelopmental Outcomes of Extremely Low Birth Weight Infants Exposed Prenatally to Dexamethasone Versus Betamethasone
Authors: Lee Ben H. , Stoll Barbara J. , McDonald Scott A. , Higgins Rosemary D. ,   for the National Institute of Child Health and Human Development Neonatal Research Network
Published: February 2008

OBJECTIVE. We compared the development of adverse neurodevelopmental outcomes at corrected ages of 18 to 22 months for extremely low birth weight infants exposed prenatally to dexamethasone, betamethasone, or no steroid.

METHODS. Study infants were extremely low birth weight (401–1000 g) infants who were in the care of National Institute of Child Health and Human Development Neonatal Research Network centers between January 1, 2002, and April 30, 2003; they were assessed neurodevelopmentally at corrected ages of 18 to 22 months. Outcomes were defined as Bayley Scales of Infant Development-II Mental Development Index of <70, Bayley Scales of Infant Development-II Psychomotor Development Index of <70, bilateral blindness, bilateral hearing aid use, cerebral palsy, and neurodevelopmental impairment. Neurodevelopmental impairment was defined as ≥1 of the aforementioned outcomes.

RESULTS. A total of 1124 infants met entry criteria. There were no statistically significant associations between prenatal dexamethasone exposure and any follow-up outcome, compared with no prenatal steroid exposure. Prenatal betamethasone exposure was associated with reduced risks of hearing impairment and neurodevelopmental impairment and with increased likelihood of unimpaired status, compared with no prenatal steroid exposure. Compared with betamethasone, dexamethasone was associated with a trend for increased risk of Psychomotor Development Index of <70, increased risk of hearing impairment, and decreased likelihood of unimpaired status.

CONCLUSIONS. Prenatal betamethasone exposure was associated with increased likelihood of unimpaired neurodevelopmental status and reduced risk of hearing impairment at corrected ages of 18 to 22 months among extremely low birth weight infants, compared with prenatal dexamethasone exposure or no prenatal steroid exposure. Pending a randomized, clinical trial, it may be in the best interests of infants to receive betamethasone, rather than dexamethasone, when possible.
Etiologic Classification of Attention-Deficit/Hyperactivity Disorder
Authors: Millichap J. Gordon
Published: February 2008

Attention-deficit/hyperactivity disorder is a neurobiological syndrome with an estimated prevalence among children and adolescents of 5%. It is a highly heritable disorder, but acquired factors in etiology are sometimes uncovered that may be amenable to preventive measures or specific therapy. Early reports have described symptoms similar to attention-deficit/hyperactivity disorder that followed brain trauma or viral encephalitis, and recent MRI studies have demonstrated brain volumetric changes that may be involved in the pathophysiology of the syndrome. The American Psychiatric Association's Diagnostic Statistical Manual, introduced in 1968, emphasizes symptomatic criteria in diagnosis. Here, an overview of environmental factors in the etiology of attention-deficit/hyperactivity disorder is presented to encourage more emphasis and research on organic causal factors, preventive intervention, and specific therapies. An organic theory and the genetic and biochemical basis of attention-deficit/hyperactivity disorder are briefly reviewed, and an etiologic classification is suggested. Environmental factors are prenatal, perinatal, and postnatal in origin. Pregnancy- and birth-related risk factors include maternal smoking and alcohol ingestion, prematurity, hypoxic-ischemic encephalopathy, and thyroid deficiency. Childhood illnesses associated with attention-deficit/hyperactivity disorder include virus infections, meningitis, encephalitis, head injury, epilepsy, toxins, and drugs. More controversial factors discussed are diet-related sensitivities and iron deficiency. Early prenatal recognition, prevention, and treatment of environmental etiologies of attention-deficit/hyperactivity disorder may reduce physician reliance on symptomatic modification with medication, a frequent reason for parental concern.
Recognition and Diagnosis of Mucopolysaccharidosis II (Hunter Syndrome)
Authors: Martin Rick , Beck Michael , Eng Christine , Giugliani Roberto , Harmatz Paul , Muñoz Verónica , Muenzer Joseph
Published: February 2008

Mucopolysaccharidosis II, also known as Hunter syndrome, is a rare, X-linked disorder caused by a deficiency of the lysosomal enzyme iduronate-2-sulfatase, which catalyzes a step in the catabolism of glycosaminoglycans. In patients with mucopolysaccharidosis II, glycosaminoglycans accumulate within tissues and organs, contributing to the signs and symptoms of the disease. Mucopolysaccharidosis II affects multiple organs and physiologic systems and has a variable age of onset and variable rate of progression. Common presenting features include excess urinary glycosaminoglycan excretion, facial dysmorphism, organomegaly, joint stiffness and contractures, pulmonary dysfunction, myocardial enlargement and valvular dysfunction, and neurologic involvement. In patients with neurologic involvement, intelligence is impaired, and death usually occurs in the second decade of life, whereas those patients with minimal or no neurologic involvement may survive into adulthood with normal intellectual development. Enzyme replacement therapy has emerged as a new treatment for mucopolysaccharidosis disorders, including Hunter syndrome. The purpose of this report is to provide a concise review of mucopolysaccharidosis II for practitioners with the hope that such information will help identify affected boys earlier in the course of their disease.
Infectious Disease Hospitalizations Among Infants in the United States
Authors: Yorita Krista L. , Holman Robert C. , Sejvar James J. , Steiner Claudia A. , Schonberger Lawrence B.
Published: February 2008

OBJECTIVE. This study describes the burden and epidemiologic features of infectious disease hospitalizations among infants in the United States.

METHODS. Hospitalizations with an infectious disease listed as a primary diagnosis for infants (<1 year of age) in the United States during 2003 were examined by using the Kids' Inpatient Database. National estimates of infectious disease hospitalizations, hospitalization rates, and various hospital parameters were examined.

RESULTS. During 2003, an estimated 286739 infectious disease hospitalizations occurred among infants in the United States and accounted for 42.8% of all infant hospitalizations. The national infectious disease hospitalization rate was 7010.8 hospitalizations per 100000 live births, or ∼1 infectious disease hospitalization for every 14 infants. The median length of stay was 3 days, and stays totaled >1 million hospital days for infants. Infectious disease hospitalization rates were highest among boys and nonwhite infants. The most commonly listed diagnoses among the infant infectious disease hospitalizations included lower respiratory tract infections (59.0%), kidney, urinary tract, and bladder infections (7.6%), upper respiratory tract infections (6.5%), and septicemia (6.5%). The median cost of an infectious disease hospitalization was $2235, with total annual hospital costs of approximately $690 million, among infants in the United States.

CONCLUSIONS. Infectious disease hospitalizations among infants account for substantial health care expenditures and hospital time in the United States, with respiratory disease hospitalizations constituting more than one half of all hospitalizations. Younger infants, boys, and nonwhite infants were at increased risk for infectious disease hospitalization. Measures to reduce racial disparities and the occurrence of respiratory tract infections should substantially decrease the infectious disease burden among infants.
The Human Capacity to Thrive in the Face of Potential Trauma
Authors: Bonanno George A. , Mancini Anthony D.
Published: February 2008

For decades, researchers have documented remarkable levels of resilience in children who were exposed to corrosive early environments, such as those in which poverty or chronic maltreatment were present; however, relatively little research has examined resilience in children or adults who were exposed to isolated and potentially traumatic events. The historical emphasis on psychological and physiologic dysfunction after potentially traumatic events has suggested that such events almost always produce lasting emotional damage. Recent research, however, has consistently shown that across different types of potentially traumatic events, including bereavement, serious illness, and terrorist attack, upward of 50% of people have been found to display resilience. Research has further identified substantial individual variation in response to potentially traumatic events, including 4 prototypical and empirically derived outcome trajectories: chronic dysfunction, recovery, resilience, and delayed reactions. Factors that promote resilience are heterogeneous and include a variety of person-centered variables (eg, temperament of the child, personality, coping strategies), demographic variables (eg, male gender, older age, greater education), and sociocontextual factors (eg, supportive relations, community resources). It is surprising that some factors that promote resilience to potentially traumatic events may be maladaptive in other contexts, whereas other factors are more broadly adaptive. Given the growing evidence that resilience is common, psychotherapeutic treatment should be reserved for those in genuine need.
Examination of US Puberty-Timing Data from 1940 to 1994 for Secular Trends: Panel Findings
Authors: Euling Susan Y. , Herman-Giddens Marcia E. , Lee Peter A. , Selevan Sherry G. , Juul Anders , SØrensen Thorkild I. A. , Dunkel Leo , Himes John H. , Teilmann Grete , Swan Shanna H.
Published: February 2008

Whether children, especially girls, are entering and progressing through puberty earlier today than in the mid-1900s has been debated. Secular trend analysis, based on available data, is limited by data comparability among studies in different popu-lations, in different periods of time, and using different methods. As a result, conclusions from data comparisons have not been consistent. An expert panel was asked to evaluate the weight of evidence for whether the data, collected from 1940 to 1994, are sufficient to suggest or establish a secular trend in the timing of puberty markers in US boys or girls. A majority of the panelists agreed that data are sufficient to suggest a trend toward an earlier breast development onset and menarche in girls but not for other female pubertal markers. A minority of panelists concluded that the current data on girls' puberty timing for any marker are insufficient. Almost all panelists concluded, on the basis of few studies and reliability issues of some male puberty markers, that current data for boys are insufficient to evaluate secular trends in male pubertal development. The panel agreed that altered puberty timing should be considered an adverse effect, although the magnitude of change considered adverse was not assessed. The panel recommended (1) additional analyses of existing puberty-timing data to examine secular trends and trends in the temporal sequence of pubertal events;(2) the development of biomarkers for pubertal timing and methods to discriminate fat versus breast tissue, and (3) establishment of cohorts to examine pubertal markers longitudinally within the same individuals.
Public Health Implications of Altered Puberty Timing
Authors: Golub Mari S. , Collman Gwen W. , Foster Paul M.D. , Kimmel Carole A. , Rajpert-De Meyts Ewa , Reiter Edward O. , Sharpe Richard M. , Skakkebaek Niels E. , Toppari Jorma
Published: February 2008

Changes in puberty timing have implications for the treatment of individual children, for the risk of later adult disease, and for chemical testing and risk assessment for the population. Children with early puberty are at a risk for accelerated skeletal maturation and short adult height, early sexual debut, potential sexual abuse, and psychosocial difficulties. Altered puberty timing is also of concern for the development of reproductive tract cancers later in life. For example, an early age of menarche is a risk factor for breast cancer. A low age at male puberty is associated with an increased risk for testicular cancer according to several, but not all, epidemiologic studies. Girls and, possibly, boys who exhibit premature adrenarche are at a higher risk for developing features of metabolic syndrome, including obesity, type 2 diabetes, and cardiovascular disease later in adulthood. Altered timing of puberty also has implications for behavioral disorders. For example, an early maturation is associated with a greater incidence of conduct and behavior disorders during adolescence. Finally, altered puberty timing is considered an adverse effect in reproductive toxicity risk assessment for chemicals. Recent US legislation has mandated improved chemical testing approaches for protecting children's health and screening for endocrine-disrupting agents, which has led to changes in the US Environmental Protection Agency's risk assessment and toxicity testing guidelines to include puberty-related assessments and to the validation of pubertal male and female rat assays for endocrine screening.
Guided Differentiation of Embryonic Stem Cells into Pdx1-Expressing Regional-Specific Definitive Endoderm
Authors: Shiraki Nobuaki , Yoshida Tetsu , Araki Kimi , Umezawa Akihiro , Higuchi Yuichiro , Goto Hideo , Kume Kazuhiko , Kume Shoen
Published: February 2008

The generation of specific lineages of the definitive endoderm from embryonic stem (ES) cells is an important issue in developmental biology, as well as in regenerative medicine. This study demonstrates that ES cells are induced sequentially into regional-specific gut endoderm lineages, such as pancreatic, hepatic, and other cell lineages, when they are cultured directly on a monolayer of mesoderm-derived supporting cells. A detailed chronological analysis revealed that Activin, fibroblast growth factor, or bone morphogenetic protein signals are critical at various steps and that additional short-range signals are required for differentiation into Pdx1-expressing cells. Under selective culture conditions, definitive endoderm (47%) or Pdx1-positive pancreatic progenitors (30%) are yielded at a high efficiency. When transplanted under the kidney capsule, the Pdx1-positive cells further differentiated into all three pancreatic lineages, namely endocrine, exocrine, and duct cells.

Disclosure of potential conflicts of interest is found at the end of this article.
Directed Differentiation of Ventral Spinal Progenitors and Motor Neurons from Human Embryonic Stem Cells by Small Molecules
Authors: Li Xue-Jun , Hu Bao-Yang , Jones Stefanie A. , Zhang Ying-Sha , LaVaute Timothy , Du Zhong-Wei , Zhang Su-Chun
Published: February 2008

Specification of distinct cell types from human embryonic stem cells (hESCs) is key to the potential application of these naïve pluripotent cells in regenerative medicine. Determination of the nontarget differentiated populations, which is lacking in the field, is also crucial. Here, we show an efficient differentiation of motor neurons (∼50%) by a simple sequential application of retinoid acid and sonic hedgehog (SHH) in a chemically defined suspension culture. We also discovered that purmorphamine, a small molecule that activates the SHH pathway, could replace SHH for the generation of motor neurons. Immunocytochemical characterization indicated that cells differentiated from hESCs were nearly completely restricted to the ventral spinal progenitor fate (NKX2.2+, Irx3+, and Pax7−), with the exception of motor neurons (HB9+) and their progenitors (Olig2+). Thus, the directed neural differentiation system with small molecules, even without further purification, will facilitate basic and translational studies using human motoneurons at a minimal cost.

Disclosure of potential conflicts of interest is found at the end of this article.
Efficient Differentiation of Hepatocytes from Human Embryonic Stem Cells Exhibiting Markers Recapitulating Liver Development In Vivo
Authors: Hay David C. , Zhao Debiao , Fletcher Judy , Hewitt Zoë A. , McLean Doris , Urruticoechea-Uriguen Alai , Black James R. , Elcombe Cliff , Ross James A. , Wolf Roland , Cui Wei
Published: February 2008

The potential to differentiate human embryonic stem cells (hESCs) in vitro to provide an unlimited source of human hepatocytes for use in biomedical research, drug discovery, and the treatment of liver diseases holds great promise. Here we describe a three-stage process for the efficient and reproducible differentiation of hESCs to hepatocytes by priming hESCs towards definitive endoderm with activin A and sodium butyrate prior to further differentiation to hepatocytes with dimethyl sulfoxide, followed by maturation with hepatocyte growth factor and oncostatin M. We have demonstrated that differentiation of hESCs in this process recapitulates liver development in vivo: following initial differentiation, hESCs transiently express characteristic markers of the primitive streak mesendoderm before turning to the markers of the definitive endoderm; with further differentiation, expression of hepatocyte progenitor cell markers and mature hepatocyte markers emerged sequentially. Furthermore, we have provided evidence that the hESC-derived hepatocytes are able to carry out a range of hepatocyte functions: storage of glycogen, and generation and secretion of plasma proteins. More importantly, the hESC-derived hepatocytes express several members of cytochrome P450 isozymes, and these P450 isozymes are capable of converting the substrates to metabolites and respond to the chemical stimulation. Our results have provided evidence that hESCs can be differentiated efficiently in vitro to functional hepatocytes, which may be useful as an in vitro system for toxicity screening in drug discovery.

Disclosure of potential conflicts of interest is found at the end of this article.