Body fat differences by self-reported race/ethnicity in healthy term newborns.

BACKGROUND: Ethnic differences in total body fat (fat mass [FM]) have been reported in adults and children, but the timing of when these differences manifest and whether they are present at birth are unknown. OBJECTIVES: This study aimed to assess whether ethnic differences in body fat are present at birth in healthy infants born at term, where body fat is measured using air displacement plethysmography and fat distribution by skin-fold thickness. METHODS: Data were from a multiracial cross-sectional convenience sample of 332 term infants from four racial or ethnic groups based on maternal self-report (A, Asian; AA, non-Hispanic Black [African-American]; C, non-Hispanic White; and H, Hispanic). The main outcome measure was infant body fat at 1-3 days after birth, with age, birth weight, gestational age and maternal pre-pregnancy weight as covariates. RESULTS: Significant effects for race (P = 0.0011), sex (P = 0.0051) and a race by sex interaction (P = 0.0236) were found. C females had higher FM than C males (P = 0.0001), and AA females had higher FM than AA males (P = 0.0205). C males had less FM than A males (P = 0.0353) and H males (P = 0.0001). CONCLUSION: Race/ethnic and sex differences in FM are present in healthy term newborns. Although the implications of these differences are unclear, studies beginning in utero and birth set the stage for a life course approach to understanding disease later in life.

Body composition during fetal development and infancy through the age of 5 years.

Fetal body composition is an important determinant of body composition at birth, and it is likely to be an important determinant at later stages in life. The purpose of this work is to provide a comprehensive overview by presenting data from previously published studies that report on body composition during fetal development in newborns and the infant/child through 5 years of age. Understanding the changes in body composition that occur both in utero and during infancy and childhood, and how they may be related, may help inform evidence-based practice during pregnancy and childhood. We describe body composition measurement techniques from the in utero period to 5 years of age, and identify gaps in knowledge to direct future research efforts. Available literature on chemical and cadaver analyses of fetal studies during gestation is presented to show the timing and accretion rates of adipose and lean tissues. Quantitative and qualitative aspects of fetal lean and fat mass accretion could be especially useful in the clinical setting for diagnostic purposes. The practicality of different pediatric body composition measurement methods in the clinical setting is discussed by presenting the assumptions and limitations associated with each method that may assist the clinician in characterizing the health and nutritional status of the fetus, infant and child. It is our hope that this review will help guide future research efforts directed at increasing the understanding of how body composition in early development may be associated with chronic diseases in later life.

Maternal obesity influences the relationship between location of neonate fat mass and total fat mass.

BACKGROUND: It is suggested that maternal obesity perpetuates offspring obesity to future generations. OBJECTIVE: To determine whether location of neonate fat mass (FM: central vs. peripheral) is related to total neonate FM and whether maternal obesity influences this relationship. METHODS: Neonate body composition and skin-fold thicknesses were assessed in healthy neonates (n = 371; 1-3 days old). Linear regression models examined the relationship between total FM and location of FM (central vs. peripheral). Location of FM was calculated by skin-folds: peripheral was the sum of (biceps and triceps)/2 and central was represented by the subscapular skin-fold. RESULTS: A significant interaction was found for location of FM and maternal obesity. Holding all predictors constant, in offspring born to non-obese mothers, a 0.5 mm increase in central FM predicted a 15 g greater total FM, whereas a 0.5 mm increase in peripheral FM predicted a 66 g greater total FM. However, in offspring born to obese mothers, a 0.5 mm increase in central FM predicted a 56 g total FM, whereas a 0.5 mm increase in peripheral FM predicted a 14 g greater total FM. CONCLUSIONS: The relationship between total FM and location of FM is influenced by maternal obesity.

Assortative mating and mutation diffusion in spatial evolutionary systems.

The influence of spatial structure on the equilibrium properties of a sexual population model defined on networks is studied numerically. Using a small-world-like topology of the networks as an investigative tool, the contributions to the fitness of assortative mating and of global mutant spread properties are considered. Simple measures of nearest-neighbor correlations and speed of spread of mutants through the system have been used to confirm that both of these dynamics are important contributory factors to the fitness. It is found that assortative mating increases the fitness of populations. Quick global spread of favorable mutations is shown to be a key factor increasing the equilibrium fitness of populations.

Temporal and dimensional effects in evolutionary graph theory.

The spread in time of a mutation through a population is studied analytically and computationally in fully connected networks and on spatial lattices. The time t* for a favorable mutation to dominate scales with the population size N as N(D+1)/D in D-dimensional hypercubic lattices and as NlnN in fully-connected graphs. It is shown that the surface of the interface between mutants and nonmutants is crucial in predicting the dynamics of the system. Network topology has a significant effect on the equilibrium fitness of a simple population model incorporating multiple mutations and sexual reproduction.

Thrombocytopenia absent corpus callosum syndrome: third case of a distinct clinical entity.

Thrombocytopenia absent corpus callosum, characterized by refractory thrombocytopenia, agenesis of the corpus callosum, hypoplastic cerebellum, abnormal facies, and developmental delay, represents a relatively newly described clinical entity. An 18-month-old girl with agenesis of the corpus callosum, hypoplasia of the cerebellar vermis, hypotonia, and severe developmental delay presented with thrombocytopenia. She had a distinctive facies with microcephaly, broad nasal root with upturned nose, small upper lip, and micrognathia. A bone marrow aspirate and biopsy showed normal cellularity with dysplastic megakaryocytes. Thrombocytopenia absent corpus callosum is compared with other conditions characterized by congenital non-immune thrombocytopenia.

Papillary-cystic neoplasm of the pancreas.

Papillary-cystic neoplasm of the pancreas is a rare, nonfunctioning low-grade malignant tumor seen in young patients, most often female. Ultrasound and CT show a circumscribed, solid nonhomogeneous mass with cystic areas, with peripheral but not central enhancement and occasional calcification. Prognosis after excision is usually excellent. We describe a case of the papillary-cystic neoplasm of the pancreas in a 13-year-old girl to illustrate the radiological findings.

Systemic necrotizing vasculitis associated with childhood sarcoidosis.

Childhood sarcoidosis is a rare disorder with protean manifestations. The case of a child with prolonged fever, hepatosplenomegaly, pancytopenia, and systemic necrotizing vasculitis manifesting as fever, rash and skin infarctions, digital pregangrene, and foot drop is reported. This is the first case of systemic necrotizing vasculitis reported in sarcoidosis. The fulminant course of the disease required treatment with intravenous pulsed cyclophosphamide and high doses of corticosteroids. The spectrum of vasculitis in childhood and adult sarcoidosis is reviewed.

Erythrocyte-depleted allogeneic human umbilical cord blood transplantation.

Cord blood is a recently recognized source of hematopoietic stem cells. It can be employed successfully to reconstitute hematopoiesis following allogeneic transplantation. One current drawback of cord blood as a treatment has been a risk of transfusion reactions attributable to ABO blood group mismatch. Removal of red cells from the cord blood has led to reduction of the stem cells by 30-50%. In this paper we report red cell depletion by a method that employs 3% gelatin to effectively sediment the erythrocytes and selectively deplete red cells but permits 94% recovery of nucleated cells and enrichment of colony-forming cells by granulocyte-macrophage colony-forming units, erythrocyte burst-forming units, and granulocyte-macrophage-megakaryocyte colony-forming units in the cord blood preparation. This technique has been employed in our study to remove red cells from the cord blood of a male infant delivered by cesarean section, which has permitted treatment of a female sibling suffering from leukemia. The recipient was 8 years old and weighted 36.7/kg. Complete HLA identity between the two siblings was established. A cord blood cell transplant of cryopreserved and later thawed cells (4 x 10(7) nucleated cells per kilogram) was administered to the patient after intensive myeloablative chemotherapy. The patient exhibited a prompt hematologic recovery (absolute neutrophil count > 500 by day 31, 100% male cells in bone marrow and peripheral blood by day 25) and has experienced a 13-month disease-free survival to date.(ABSTRACT TRUNCATED AT 250 WORDS)