The human adipose tissue is a source of multipotent stem cells

Multipotent stem cells constitute an unlimited source of differentiated cells that could be used in pharmacological studies and in medicine. Recently, several publications have reported that adipose tissue contains a population of cells able to differentiate into different cell types including adipocytes, osteoblasts, myoblasts, and chondroblasts. More recently, stem cells with a multi-lineage potential at the single cell level have been isolated from human adipose tissue. These cells, called human Multipotent Adipose-Derived Stem (hMADS) cells, have been established in culture and interestingly, maintain their characteristics with long-term passaging. The adipocyte differentiation of hMADS cells has been thoroughly studied and differentiated cells exhibit the unique feature of human adipocytes. Finally, potential applications of stem cells isolated from adipose tissue in medicine will be discussed.

Cloning of hOST-PTP: the only example of a protein-tyrosine-phosphatase the function of which has been lost between rodent and human

Protein-tyrosine-phosphatases (PTP-ases), in concert with protein tyrosine kinases, control various biological activities such as cell growth and differentiation. In rodents, around 40 PTP-ases have been described. Functional orthologue for each of these PTP-ases have been identified in human, except for OST-PTP. OST-PTP is a transmembrane PTP-ase with a restricted tissue distribution. In silico analysis on public sequence databases reveals a human OST-PTP gene orthologue that encompasses 21 kb on chromosome 1q32.1. Using RT-PCR we isolated a 4 kb hOST-PTP transcript. hOST-PTP cDNA sequence exhibits numerous disablements indicating that it does not code for a PTP-ase but is rather a pseudogene with unique features. Indeed, (i) it has no "functional" parent in the human genome, (ii) it has retained an "intron-exon" structure, and (iii) it is transcribed in a regulated manner. Interestingly, we found two ESTs, from domesticated pig and from cow that exhibit ORF that would predict a functional OST-PTP orthologue in Artiodactyls. Taken together, these results indicate that OST-PTP is the only PTP-ase the function of which has been lost during the evolution process between rodents and human.

Effect of blood transfusions on oxidative stress in preterm infants

OBJECTIVE

To confirm the increase in non-transferrin bound iron (NTBI) after packed red cell (PRC) transfusion and to evaluate the association with increased oxidative stress in preterm infants.

METHOD

Twenty healthy preterm infants (gestational age 28.2 (2.2) weeks; birth weight 1047 (230) g), who required blood transfusion for anaemia of prematurity were prospectively studied. Serum concentrations of NTBI, total hydroperoxides (TH), and protein SH groups, and plasma total radical trapping antioxidant capability (TAC) were measured within three hours before and after PRC transfusion. The infants were transfused with 38.6 (23) ml PRCs over 5.8 (1.0) hours, at a mean age of 43.3 (25.1) days.

RESULTS

After PRC transfusion, haemoglobin concentration increased from 9.2 (1.1) to 14.6 (1.5) g/l. Mean plasma NTBI concentration after transfusion was significantly higher (0.43 (0.45) v 2.03 (1.31) micromol/l; p = 0.001), while plasma concentrations of TH (212.3 (42.2) v 214.7 (66.3) Carr units/l) and protein SH groups (317.5 (38.8) v 353.8 (57.4) micromol/), and TAC (256.3 (36.1) v 267.1 (42.4) micromol HClO/ml) remained unchanged.

CONCLUSION

For three hours after PRC transfusion, plasma NTBI is significantly increased in preterm infants, but this is not associated with significant changes in oxidative stress.

Role of oxidative stress as physiopathologic factor in the preterm infant

Oxidative stress usually occurs when the production of damaging free radicals (ROS) and other oxidative molecules exceeds the capacity of the body's antioxidant defenses. This process is supposed to begin after the delivery, but it can even affect the fetus when maternal pregnancy diseases (i.e.: pre-eclampsia, eclampsia, maternal infections) occur and in the case of preterm delivery. Most living organisms have developed well integrated antioxidant defenses to prevent the potential negative role of the ROS, in order to scavenge them and to control their concentration. These mechanisms are deficient in preterm newborn. Many illnesses in preterm infants, including bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), brain injury such as hypoxic/ischemic encephalopathy, and intraventricular hemorrhage (IVH) are thought to be related to the action of ROS. This presumably occurs due to the fact that the antioxidant system of preterm infants is at the same time highly stressed and incompletely developed. Unfortunately, the clinical trials which tried to prevent oxidative stress using antioxidant agents failed their objective and therefore they cannot be considered as an effective therapy. The objective of this review is to clarify the role of oxidative stress in the development of the previous severe diseases in preterm infants, and its possible correlation with hyperbilirubemia.

Prediction of early tolerance to enteral feeding by measurement of superior mesenteric artery blood flow velocity: appropriate- versus small-for-gestational-age preterm infants

AIM

To evaluate whether serial Doppler measurements of superior mesenteric artery blood flow velocity could predict early tolerance to enteral feeding in preterm infants.

METHODS

In a prospective study, 54 healthy preterm neonates were assigned to one of the following groups: neonates with birthweight appropriate for gestational age (group 1), neonates small for gestational age without (group 2) and with prenatal haemodynamic disturbances (group 3). We studied Doppler blood flow velocity and resistance index before and after the first feed.

RESULTS

Contrary to patients of group 3, infants in groups 1 and 2 showed a significant increase in blood flow velocity and a significant decrease in resistance index from the preprandial values after the first feed. At each postprandial time, we found significant differences in all velocity and resistance measurements between patients of group 3 and patients of both groups 1 and 2. In all patients, we found that the value of mean velocity measured 30 min after the first feed was the most predictive of early feed tolerance, with 95% sensitivity and 94% specificity when mean velocity >0.38 m/s.

CONCLUSION

Small-for-gestational-age preterm infants with prenatal haemodynamic disturbances have an unusual intestinal haemodynamic response to the first feed. In the whole group of preterm infants, the value of mean velocity measured 30 min after the first feed is a good tool for the clinician in predicting early enteral feeding.

Redox Status in Very-Low Birth-Weight Newborns

Inborn metabolic diseases, such as disorders in pyruvate metabolism, in gluconeogenesis or in the respiratory chain, may present with lactic acidosis in newborn infants. A simple tool to screen for the efficacy of mitochondrial oxidation reduction activity is the detection of the redox status through simultaneous measurements of plasma lactate, pyruvate and ketone bodies, which are strongly influenced by feeding and stress. We present the redox status values of 55 very-low birth-weight infants under different nutritional conditions. We were able to demonstrate that the redox status values are not dependent on the type of nutrition (oral feeding or continuous enteral nutrition). Instead we observed a strong difference between newborns with intrauterine growth retardation and newborns with appropriate growth. Newborns with intrauterine growth retardation show lower preprandial values of glucose and ketone bodies than newborns with appropriate weight, but higher levels of lactate and pyruvate; nevertheless the lactate/pyruvate and beta-hydroxybutyrate/acetoacetate ratios are normal. The results of the redox status study could suggest the reduced activity of gluconeogenesis and, probably, of beta-oxidation in very-low birth-weight newborns with intrauterine growth retardation.

Perfluorocarbons attenuate oxidative lung damage

The aim of this study was to investigate the effect of tidal liquid ventilation (TLV) compared to conventional mechanical ventilation (CMV) on oxidative lung damage in the setting of acute respiratory distress syndrome (ARDS). After repeated lung lavages, 10 minipigs were treated with CMV or TLV for 4 hr before the animals were sacrificed. Samples for blood gas analysis and bronchial aspirate samples were withdrawn before the induction of lung injury, and at 10 min, 2 hr, and 4 hr after the beginning of ventilatory support. To assess lung oxidative damage, total hydroperoxide (TH) and advanced oxidation protein product (AOPP) concentrations were measured in bronchial aspirate samples. After 2 and 4 hr of ventilatory support, partial oxygen tension (PaO(2)) and base excess (BE) were significantly higher in the TLV group than in the CMV group, while PaCO(2) was slightly higher, but with no statistical significance. In the CMV group, the AOPP level was significantly higher at 4 hr than at baseline. TH and AOPP bronchial aspirate concentrations were higher in the CMV group than in the TLV group at 2 and 4 hr of ventilation. We conclude that animals treated with TLV showed lower oxidative lung damage compared to animals treated with CMV.

Pharmacokinetics of oxatomide in preterm infants

The pharmacokinetics and tolerability of oxatomide oral suspension were investigated in preterm infants to evaluate the feasibility of planning a further study to assess its antiinflammatory effects and its effectiveness in preventing chronic lung disease (CLD). Following the administration of oxatomide 1 mg/kg, the peak plasma concentration (Cmax), the elimination half-life (t1/2), the volume of distribution (Vd), and the area under the curve (AUC) 0-36 h were measured and the following results were obtained: 42.2 +/- 15 ng/ml at 2 h after oxatomide administration, 41.4 +/- 2.0 h, 37.4 +/- 4.2 l/kg, and 468 +/- 52 ng/ml/h, respectively. Our study, therefore, demonstrated that a dose of 1 mg/kg/day oxatomide was effective in reaching therapeutic plasma levels in preterm infants without inducing adverse effects.

Plasma bilirubin level and oxidative stress in preterm infants

OBJECTIVE

To assess the hypothesis that changes in plasma total bilirubin levels (Btot) can influence the antioxidant system and oxidative stress in preterm infants.

METHODS

Twenty two healthy preterm infants who presented with visible non-haemolytic hyperbilirubinaemia were studied at the mean (SD) age of 3.7 (1.5) days. Btot, plasma total hydroperoxide concentration (TH), plasma protein SH group concentration, and total antioxidant capacity of the plasma (TAC) were measured at study entry and after 24 hours.

RESULTS

Btot did not correlate with TH, TAC, or protein SH group concentration, but a significant correlation was found between TH and TAC, TH and protein SH groups, and TAC and protein SH groups, both at study entry and after 24 hours.

CONCLUSION

The decrease in plasma bilirubin was contemporary with an increase in plasma antioxidant capacity and decrease in oxidative stress in preterm infants. This may be the result of the pro-oxidant effect of haem oxygenase, mediated by iron release, which may outcompete the antioxidant properties of bilirubin.

Effect of blood transfusions on cerebral haemodynamics in preterm infants

AIM

To assess the possible cerebral haemodynamic changes occurring in preterm infants after blood transfusions.

METHODS

Preterm infants who had undergone blood transfusions were prospectively studied using both near infrared spectroscopy and cerebral Doppler ultrasonography.

RESULTS

Fourteen infants (mean gestational age 29.6 wk, SD 2.6; mean birthweight 1,430g, SD 332) were studied at the mean age of 29 (SD 14) d. A significant increase in oxygenated haemoglobin (O2Hb), deoxygenated haemoglobin (HHb), mixed cerebral oxygen saturation (SmO2) and change in cerebral blood volume occurred after transfusion. Between ultrasound parameters, we found a decrease in diastolic velocity and an increase in resistance index.

CONCLUSION

Blood transfusions improve cerebral oxygen supply and induce a decrease in cerebral blood volume, probably due to an increase in cerebral vessel resistance.

Haemodynamic changes in the brain after vaginal delivery and caesarean section in healthy term infants

OBJECTIVE

To investigate whether the mode of delivery may affect neonatal cerebral haemodynamics during the first hour of life.

DESIGN

Prospective study.

SAMPLE

Healthy infants with gestational age > or =37 weeks and birthweight appropriate for gestational age, born after uncomplicated pregnancy by vaginal delivery or elective caesarean section, two to five hours after the delivery.

METHODS

Near infra-red spectroscopy was used to measure changes of oxygenated haemoglobin, deoxygenated haemoglobin, oxidized-reduced cytochrome aa3, and mean cerebral oxygen saturation (mixed cerebral oxygen saturation = oxygenated haemoglobin/total haemoglobin). Changes in cerebral blood volume were calculated.

RESULTS

Near infra-red spectroscopy data did not show significant differences between infants born by vaginal delivery or by caesarean section. There was a significant decrease of oxygenated haemoglobin and change of cerebral blood volume values at 120 and 180 minutes in both the groups, while deoxygenated haemoglobin and oxidized-reduced cytochrome aa3 were unchanged.

CONCLUSIONS

A decrease of cerebral blood volume occurs after birth and this occurs both in infants born by vaginal delivery and by caesarean section.

PPARgamma-dependent and PPARgamma-independent effects on the development of adipose cells from embryonic stem cells

Peroxisome proliferator-activated receptor (PPAR) gamma was shown to be required for adipocyte formation both in vivo and in vitro. However, the role of PPARgamma in the initial steps of adipose cell development was not distinguished from its role in the terminal steps. We now show that PPARgamma is expressed early in embryoid bodies (EBs) derived from embryonic stem cells and in E.8.5 mouse embryos. Addition of a specific ligand for PPARgamma in developing EBs over-expressing PPARgamma did not commit stem cells towards the adipose lineage. In differentiated PPARgamma(-/-) EBs, only markers characteristic of preadipocytes were found to be expressed. PPARdelta is present in EBs but did not compensate for the lack of PPARgamma in terminal differentiation. Taken together, these results favor a critical PPARgamma-independent phase culminating in preadipocyte formation that precedes a PPARgamma-dependent phase in the development of adipose cells from pluripotent stem cells.

Activation of extracellular signal-regulated kinases and CREB/ATF-1 mediate the expression of CCAAT/enhancer binding proteins beta and -delta in preadipocytes

The essential role of CCAAT/enhancer binding proteins (C/EBPs) beta and delta for adipocyte differentiation has been clearly established. In preadipocytes, their expression is up-regulated by the activation of leukemia inhibitory factor receptor (LIF-R) and prostacyclin receptor (IP-R) via the extracellular signal-regulated kinase (ERK) pathway and cAMP production, respectively. However, the molecular mechanisms by which LIF and prostacyclin-induced signals are propagated to the nucleus and the transcription factors mediating ERK and cAMP-induced C/EBP gene expression were unknown. Here we report that both pathways share cAMP responsive element binding protein/activation transcription factor 1 (CREB/ATF-1) as common downstream effectors. LIF-R and IP-R activation induced binding of CREB and/or ATF-1 to C/EBP promoters and CREB-dependent transcription. Expression of dominant negative forms of CREB dramatically reduced the LIF- and prostacyclin-stimulated C/EBP beta and C/EBP delta expression. Upon stimulation of the IP-R, the ERK pathway was activated in a PKA-dependent manner. ERK activation by the PKA pathway was not required for CREB/ATF-1 phosphorylation but rather was necessary for CREB-dependent up-regulation of C/EBPs expression. Our findings suggest that ERK activation is required for CREB transcriptional activity, possibly by recruitment of a coactivator.

[Prophylaxis of group B beta-hemolytic streptococcal infections]

Group B streptococcus is a possible cause of chorioamnionitis, endometritis and urinary tract infections in pregnant woman. Maternal risk factors and the vertical transmission of GBS and neonatal GBS infection occur through the following fever during labor, the rupturing of membranes more than 18 hours before delivery, prematurity and chorioamnionitis. GBS can induce early-onset neonatal disease (sepsis, meningitis or pneumonia) during the first week of life and late-onset neonatal infection (leptomeningitis) within the first 12 weeks of life. Numerous strategies for preventing neonatal group B streptococcal infection were investigated: 1) the treatment of GBS-colonized women during the third trimester of pregnancy did not prove to be effective because it does not reduce maternal colonizzation rates at delivery; 2) the neonatal universal post-partum prophylaxis with penicillin G was ineffective and increased neonatal mortality due to penicillin-resistant bacterial infection; 3) the intrapartum maternal chemoprophylaxis with penicillin G or ampicillin in GBS-colonized women, in women with risk factors, or in women with both GBS colonization and risk factors. The latter strategy proved to be the most effective because it reduces the risk of early-onset GBS infection by 75% and 95% when associated with post-neonatal prophylaxis. To date, there are no guidelines on the management of the asymptomatic neonate whose mothers have been treated with chemopropylaxis intra-partum.

Inhibition of myogenesis enables adipogenic trans-differentiation in the C2C12 myogenic cell line

C2C12 cells are a well-established model system for studying myogenesis. We examined whether inhibiting the process of myogenesis via expression of dominant negative (DN) mitogen-activated protein kinase kinase-3 (MKK3) facilitated the trans-differentiation of these cells into adipocytes. Cells expressing DN MKK3 respond to rosiglitazone, resulting in adipocyte formation. The effects of rosiglitazone appear to be potentiated through peroxisome proliferator activating receptor-gamma. This trans-differentiation is inhibited by the use of the phosphoinositide-3 (PI3) kinase inhibitor, LY294002. These results indicate that preventing myogenesis through expression of DN MKK3 facilitates adipocytic trans-differentiation, and involves PI3 kinase signalling.

Liquid ventilation in an infant with persistent interstitial pulmonary emphysema

We present the case of a full term infant affected by diffuse persistent interstitial pulmonary emphysema (PIPE), who was treated with partial liquid ventilation (PLV) after the failure of conventional management. PIPE is a lethal chronic lung disease of unclear pathogenesis. Clinical history, radiological and histological findings confirmed the diagnosis in our patient. PLV applied for 48 hours resulted in a significant improvement in the infant's respiratory function and was not associated with adverse effects. We concluded that PLV could be effective in prolonging the survival of infants with PIPE; its application represents an effective form of respiratory support in infants with chronic lung disease.

Randomised controlled trial of the effect of cisapride on the pyloric muscle in preterm infants

In this study we determined the effects of cisapride on the pyloric muscle in preterm infants. To perform a randomised, double blind, placebo controlled study, two groups each of 16 preterm newborns were given either cisapride (0.2 mg/kg every 8 h) or a placebo for at least 7 days. Infants were studied first on the day when treatment with cisapride or placebo was to be initiated (time 0), and then after 3 (time 1) and 7 days (time 2). In each group, the following parameters were studied by ultrasonography: cross-sectional diameter of the entire pylorus, muscle thickness, and length of the pyloric canal. Also, the mean daily total gastric aspirate volume was studied for the entire week of the study. At time 0, we observed no significant differences between the two groups with respect to diameter, muscle thickness and length of the pyloric muscle. At time 1 and time 2, both diameter and muscle thickness were significantly greater in the cisapride group than in the placebo group. Furthermore, the length of the pyloric canal was significantly greater in the cisapride group than in placebo group at time 2, though not so at time 1. For the entire week of the study, we found a significantly larger mean daily total gastric aspirate volume in the group of infants treated with cisapride compared to the placebo treated group.

CONCLUSION

Cisapride significantly affects all of the main measurements of the pyloric muscle and causes a significantly larger amount of daily total gastric aspirate volume. Its use to promote feeding intolerance in preterm newborns cannot be recommended.

Influence of maternal magnesium sulphate and ritodrine treatment on cerebral blood flow velocity of the preterm newborn

BACKGROUND

To evaluate the effect of antenatal tocolytic administration of magnesium sulphate and ritodrine on the cerebral blood flow velocity and on the cerebral vascular resistance of preterm newborns in the first hours of life.

METHODS

Cerebral blood flow velocity, resistance index and relative vascular resistance were studied in 27 preterm infants (<34 weeks gestation) with antenatal exposure to maternal magnesium sulphate treatment and in 27 preterm infants (<34 weeks gestation) with antenatal exposure to maternal ritodrine treatment. Both antenatal magnesium sulphate or ritodrine were used for tocolysis. Cerebral blood flow was measured, using Doppler ultrasonography, in the anterior cerebral artery, in the left middle cerebral artery and in the right middle cerebral artery.

RESULTS

We did not find any significant difference in the blood flow velocity, resistance index or relative vascular resistance in the three cerebral arteries between the two treatment groups.

CONCLUSIONS

Our study shows that maternal antenatal administration of magnesium sulphate to delay preterm delivery, compared to antenatal administration of ritodrine, does not induce any significant differences either in cerebral blood flow velocity or in cerebral vascular resistance of preterm infants in the first hours of life.

Combined regimen of cisplatin, doxorubicin, and alpha-2b interferon in the treatment of advanced malignant pleural mesothelioma: a Phase II multicenter trial of the Italian Group on Rare Tumors (GITR) and the Italian Lung Cancer Task Force (FONICAP)

BACKGROUND

The cisplatin-doxorubicin combination has shown moderate activity in malignant pleural mesothelioma (MPM; objective response, 25%), and preclinical studies suggest that interferons (IFNs) may have an antiproliferative effect on mesothelioma cell lines with a marked increase in cisplatin cytotoxicity. Therefore, the combined chemoimmunotherapy regimen is an worthwhile approach to evaluate in a Phase II trial.

METHODS

From December 1995 to June 1999, 37 previously untreated patients with MPM were treated with cisplatin 60 mg/m(2) intravenously on Day 1 plus doxorubicin 60 mg/m(2), recycled every 3-4 weeks and IFN-alpha-2b, 3 x 10((6)) international units subcutaneously 3 times a week for a total of 6 courses or until progression. Inclusion criteria were histologic diagnosis of MPM and measurable disease defined by computed tomography scan or magnetic resonance imaging.

RESULTS

Thirty-four patients were assessable for toxicity and 35 for efficacy according to World Health Organization criteria. One hundred thirty-five courses were administered with a median of 4 cycles per patients. Seventy-six percent of patient presented at least 1 episode of severe myelosuppression (Grade 3 and 4). Severe anemia and thrombocytopenia occurred in 30% and 24% of patients, respectively. Sixty percent of patients presented constitutional symptoms. In the 35 patients assessable for response, the overall response rate was 29% (95% confidence interval, 15-47%). The median duration of response was 8.4 months. With a median follow-up of 19.6 months, the median survival was 9.3 months. One- and 2-year survival was 45% and 34%, respectively.

CONCLUSIONS

This combined regimen has definite activity in MPM. However, toxicity, particularly myelosuppression and fatigue, is not negligible and may limit its application.

Impaired ossification in mice lacking the transcription factor Sp3

Sp3 is a ubiquitously expressed member of the Sp family of transcription factors. Recently, the mouse Sp3 gene has been disrupted by homologous recombination. Sp3 null mice die immediately after birth due to respiratory failure. In addition, these mice show a pronounced defect in late tooth formation. Here we show that Sp3 is also required for proper skeletal ossification. Both endochondral and intramembranous ossification are impaired in E18.5 Sp3-/- embryos. The delay in ossification is reflected by reduced expression of the osteoblast-specific marker gene osteocalcin. The transcription factor - core binding factor 1 (Cbfa1)--that is essential for bone formation, however, is expressed at normal levels. In vitro differentiation studies using Sp3-/- ES cells further support the conclusion that Sp3 is needed for correct bone formation. The capacity of Sp3-/- cells to undergo osteogenic differentiation in vitro is reduced and osteocalcin expression is significantly diminished. Our studies establish Sp3 as an essential transcription factor for late bone development.

Emergence during development of the white-adipocyte cell phenotype is independent of the brown-adipocyte cell phenotype

In mammals, two types of adipose tissue are present, brown and white. They develop sequentially, as brown fat occurs during late gestation whereas white fat grows mainly after birth. However, both tissues have been shown to have great plasticity. Thus an apparent transformation of brown fat into white fat takes place during post-natal development. This observation raises questions about a possible conversion of brown into white adipocytes during development, although indirect data argue against this hypothesis. To investigate such questions in vivo, we generated two types of transgenic line. The first carried a transgene expressing Cre recombinase specifically in brown adipocytes under the control of the rat UCP1 promoter. The second corresponded to an inactive lacZ gene under the control of the human cytomegalovirus promoter. This dormant gene is inducible by Cre because it contains a Stop sequence between two loxP sequences, separating the promoter from the coding sequence. Adipose tissues of progeny derived by crossing independent lines established from both constructs were investigated. LacZ mRNA corresponding to the activated reporter gene was easily detected in brown fat and not typically in white fat, even by reverse transcriptase PCR experiments. These data represent the first direct experimental proof that, during normal development, most white adipocytes do not derive from brown adipocytes.

Prevention of bilirubin encephalopathy

Prevention of bilirubin encephalopathy is based on the detection of infants at risk of developing a significant hyperbilirubinemia. This task can be accomplished by performing a simple umbilical cord blood test, such as blood group, Rh, Coombs' test and glucose-6-phosphate dehydrogenase, in order to detect hemolytic diseases. In preterm infants, the prevention of hyperbilirubinemia with phototherapy is a relatively simple task, since these infants are cared for in hospital. Early hospital discharge of full-term neonates represents a major concern. The management of neonatal jaundice requires that therapy begins when total serum bilirubin levels are significantly below the levels at which kernicterus is considered an immediate threat. Unfortunately, determination of serum bilirubin is a painful procedure, and is not very accurate since there is a high variability in laboratory measurements. The accuracy and precision of a new transcutaneous bilirubin measurement, comparable to the standard of care laboratory test, makes the daily evaluation of transcutaneous bilirubin measurement a useful tool in distinguishing physiological from nonphysiological hyperbilirubinemia, and determining the bilirubin increment in the first days of life. Full-term neonates who lose a significant amount of weight are especially at risk of significant hyperbilirubinemia and must be treated with ad libitum feeding and intensive phototherapy.