Author by: Stephan Beck Language: en Publisher by: John Wiley & Sons Format Available: PDF, ePub, Mobi Total Read: 71 Total Download: 430 File Size: 49,7 Mb Description: This is the first book that describes the role of the Epigenome (cytosine methylation) in the interplay between nature and nurture. It focuses and stimulates interest in what will be one of the most exciting areas of post-sequencing genome science: the relationship between genetics and the environment.

Written by the most reputable authors in the field, this book is essential reading for researchers interested in the science arising from the human genome sequence and its implications on health care, industry and society. Author by: Cheryl S Rosenfeld Language: en Publisher by: Academic Press Format Available: PDF, ePub, Mobi Total Read: 51 Total Download: 325 File Size: 47,9 Mb Description: The Epigenome and Developmental Origins of Health and Disease synthesizes the existing knowledge on how the in utero environment could be the most important environment in shaping later risk for various diseases or to conversely promote the health of the offspring. The book mines the existing literature from a variety of disciplines from toxicology to nutrition to epigenetics to reveal how contrasting maternal in utero environmental changes might be leading to epigenetic convergence and the resulting deleterious phenotypic and physiological effects in our offspring.

It is increasingly becoming apparent that even subtle changes in the mother’s diet, stress, and exposure to low concentrations of toxic chemicals at levels deemed safe by the EPA and FDA, such as endocrine disrupting compounds (EDC), can dramatically impact the health of our children, possibly leading to metabolic, cardiovascular, immunological, neurobehavioral disorders, and increased risk for cancer to list but a few examples. Informs how everyday choices pregnant women make can impact child development Ties together how in utero environmental changes may be inducing epigenetic changes in the offspring leading to overlapping phenotypes regardless of the initial insult (toxic, nutrition, or stress) Includes a boxed-in area in each chapter for further references and resources to keep up with the field Features video interviews with the authors and other key leaders in the field. Author by: Thomas Woodward Language: en Publisher by: Kregel Publications Format Available: PDF, ePub, Mobi Total Read: 30 Total Download: 217 File Size: 48,9 Mb Description: In this creative and inventive treatment, authors Thomas E. Woodward and James P. Gills take readers on an exploration of the human epigenome. Acting as tour guides leading visitors through a 3-D model of a human cell, Woodward and Gills bring to life the human molecular makeup. Readers (as visitors) will get up close and personal with the minute details of human molecular structure, including E.

Thermoregulation in the Newborn. Audra McCay Prince, MD Assistant Professor of Pediatrics Arkansas Children’s Hospital & UAMS Neonatology. Heat Production.

Coli, flagellum, a DNA helix, an RNA molecule, and more. By seeing it with their own eyes, readers will gain a better understanding of their genetic systems and a better appreciation for the Creator who put this all into place. Author by: Language: en Publisher by: Format Available: PDF, ePub, Mobi Total Read: 57 Total Download: 851 File Size: 49,6 Mb Description: The initial proposal focused on developing technologies to uncover epigenetic changes that contribute to tumor development. Dvdfab Mac Serial Keygen here. The authors' initial attempts towards developing genome-wide approaches to identifying new genes silenced by epigenetic mechanisms encountered problems. However, their efforts to exploit epigenetic mechanisms of gene silencing to study tumor suppressor gene function have been very successful.

Therefore, as they enter the second year of funding, they plan to capitalize on the success of the latter experiments in refocusing their efforts. Their new objectives will build upon the unanticipated advances that they have made in the use of RNAi to manipulate gene expression in mouse and human cell systems and in animal models to explore the role of epigenetic modifications in breast cancer progression. This report presents key accomplishments in the following areas: control of cellular senescence and the silencing of E2F target genes, analysis of the CBX7 oncogene, use of ribonucleic acid interference (RNAI) to suppress gene expression and produce tumor phenotypes in mice, and RNAI libraries and other new tools.

Author by: Andreas Luch Language: en Publisher by: Springer Science & Business Media Format Available: PDF, ePub, Mobi Total Read: 91 Total Download: 546 File Size: 40,8 Mb Description: Molecular Toxicology is the first volume of a three-volume set Molecular, Clinical and Environmental Toxicology that offers a comprehensive and in-depth response to the increasing importance and abundance of chemicals in daily life. By providing intriguing insights far down to the molecular level, this work covers the entire range of modern toxicology with special emphasis on recent developments and achievements. It is written for students and professionals in medicine, science, public health and engineering who are demanding reliable information on toxic or potentially harmful agents and their adverse effects on the human body.

Author by: Anne C. Ferguson-Smith Language: en Publisher by: Springer Science & Business Media Format Available: PDF, ePub, Mobi Total Read: 32 Total Download: 155 File Size: 44,8 Mb Description: Epigenetic modifications act on DNA and its packaging proteins, the histones, to regulate genome function. Manifest as the heritable methylation of DNA and as post-translational histone modifications, these molecular flags influence the architecture and integrity of the chromosome, the accessibility of DNA to gene regulatory components and the ability of chromatin to interact within nuclear complexes.

While a multicellular individual has only one genome, it has multiple epigenomes reflecting the diversity of cell types and their properties at different times of life; in health and in disease. Relationships are emerging between the underlying DNA sequence and dynamic epigenetic states and their consequences,such as the role of RNA interference and non-coding RNA.

These integrated approaches go hand-in-hand with studies describing the genomic locations of epigenetic modifications in different cell types at different times. The excitement and curiosity surrounding epigenomics is driven by a growing community of researchers in a burgeoning field and the development of new technologies built on the backbone of genome sequencing projects. Research has shown that the adaptability and vulnerability of epigenetic states has profound effects on natural variation, the response of the genome to its environment and on health and disease. The aim of this volume is not to describe epigenomes, but rather to explore how understanding epigenomes tells us more about how biological systems work and the challenges and approaches taken to accomplish this. These contributions have attempted to integrate epigenomics into our understanding of genomes in wider context, and to communicate some of the wonders of epigenetics illustrated through examples across the biological spectrum. Author by: Ariann Crudo Language: en Publisher by: Format Available: PDF, ePub, Mobi Total Read: 61 Total Download: 288 File Size: 53,7 Mb Description: 'In late gestation, fetal endogenous glucocorticoids increase exponentially. This dramatic increase in glucocorticoids acts to mature several organ systems.

As a result, synthetic glucocorticoids (sGCs) are administered to pregnant women at risk of delivering pre-term (>10% of all pregnancies). While this treatment is highly effective in the fetal lung, little is known concerning its long-term consequences in humans. Animal studies have demonstrated that offspring prenatally exposed to sGCs are at risk of behavioral abnormalities and modifications in hypothalamic-pituitary-adrenal (HPA) axis and endocrine function; this involves long-term changes in gene expression. Author by: Howard L. Kaufman Language: en Publisher by: Springer Science & Business Media Format Available: PDF, ePub, Mobi Total Read: 90 Total Download: 444 File Size: 47,5 Mb Description: This book presents an overview of the development of targeted therapies for the treatment of cancer with an emphasis on clinical application. The volume covers the complexity of the rapidly developing area of targeted therapies for the treatment of patients with cancer.

It is structured in a way so readers may begin with chapters that most interest them and work through the rest of the chapters in the order of their choice. Author by: Moshe Szyf Language: en Publisher by: Springer Science & Business Media Format Available: PDF, ePub, Mobi Total Read: 87 Total Download: 854 File Size: 50,9 Mb Description: NA methylation has bewildered molecular biologists since Hotchkiss discovered it almost six decades ago (Hotchkiss RDJ.

Biol Cem 1948; 175:315-332). The fact that the chemical structure of our D genome consists of two components that are covalently bound, the genetic information that is replicated by the DNA replication machinery ana DNA methylation that is maintainea by independent enzymatic machinery, has redictably stimulated the imagination and curiosity of generations of mo Edular biologists. An obvious question was whether DNA methylation was a bearer of additional information to the genetic information and what was the nature of this information?

It was tempting to speculate that DNA me thylation applied some form of control over programming of the genome s expression profile. Once techniques to probe the methylation profile of whole genomes as well as specific genes became available, it became clear that DNA methylation patterns are gene and tissue specific and that patterns of gene expression correlate with patterns of methylation. DNA methylation pat terns emerged as the only component of the chemical structure of DNA that exhibited tissue and cell specificity. This data seemingly provided an attrac tively simple explanation for the longstanding dilemma of how could one identical genome manifest itself in so many different forms in multicellular organisms? The DNA methylation pattern has thus become the only known factor to confer upon DNA a unique cellular identity.

Results At 36 weeks' gestational age, 33.9% of 307 infants who were assigned to receive CPAP had died or had bronchopulmonary dysplasia, as compared with 38.9% of 303 infants who were assigned to receive intubation (odds ratio favoring CPAP, 0.80; 95% confidence interval [CI], 0.58 to 1.12; P=0.19). At 28 days, there was a lower risk of death or need for oxygen therapy in the CPAP group than in the intubation group (odds ratio, 0.63; 95% CI, 0.46 to 0.88; P=0.006). There was little difference in overall mortality. In the CPAP group, 46% of infants were intubated during the first 5 days, and the use of surfactant was halved. The incidence of pneumothorax was 9% in the CPAP group, as compared with 3% in the intubation group (P. For two decades, the standard treatment for very preterm infants was with assisted ventilation and surfactant.

However, since ventilation may damage the lungs, it has been hypothesized that the avoidance of ventilation might lead to less bronchopulmonary dysplasia. Bronchopulmonary dysplasia is a major cause of mortality and morbidity in very preterm infants. Despite the increased use of antenatal corticosteroids, surfactant, and improved ventilation techniques, the incidence has not decreased. Observational studies of variations in clinical practice have suggested that treating very preterm infants with nasal continuous positive airway pressure (CPAP) during resuscitation is possible and may reduce the intubation rate and incidence of bronchopulmonary dysplasia without increasing morbidity. Some studies have suggested that CPAP may be started at birth for most infants of more than 25 weeks' gestation. However, observational studies alone do not provide strong enough evidence to justify changing clinical practice. Studies of the early use of CPAP have cited the need for a randomized, controlled trial comparing CPAP with intubation and ventilation.

One randomized trial involving 104 infants showed the feasibility of the early use of CPAP but was not designed to evaluate safety and efficacy. In the randomized, controlled Continuous Positive Airway Pressure or Intubation at Birth (COIN) trial, we based our comparison of CPAP with intubation and ventilation on the hypothesis that the use of CPAP shortly after birth would reduce the rates of death and bronchopulmonary dysplasia (defined as the need for oxygen treatment at 36 weeks' gestational age). Study Design We organized an international, multicenter trial in perinatal centers, which was approved by the local institutional review board or ethics committee at each center. The study was funded by the Australian National Health and Medical Research Council. The trial coordinator monitored data collection, entry, and checking.

An independent data and safety monitoring committee reviewed the data after the enrollment of each group of 100 infants. The eligibility criteria for infants were a gestational age at delivery between 25 weeks 0 days and 28 weeks 6 days, no known condition that might adversely affect breathing after birth apart from prematurity, birth in a hospital participating in the trial, and an ability to breathe at 5 minutes after birth but needing respiratory support because of increased respiratory effort, grunting respiration, or cyanosis. Infants were ineligible if they had been intubated before randomization or if they required no respiratory support or oxygen. Written informed consent from parents was obtained before delivery. Study Intervention After birth, the infants received mask ventilation if required. At 5 minutes after birth, the clinician leading the resuscitation team decided whether ongoing respiratory support was needed.

If the infant fulfilled the entry criteria, the randomization envelope was opened and the allocated treatment was started immediately. Nasal CPAP was started at a pressure of 8 cm of water with short single or binasal prongs. After infants were admitted to the nursery, short binasal prongs were used. The CPAP pressure could then be altered as required.

Infants who were assigned to receive CPAP were intubated and underwent ventilation only if they had any of the following symptoms: apnea unresponsive to stimulation and methlyxanthine treatment (>6 episodes requiring stimulation in 6 hours or requiring >1 episode of positive-pressure ventilation), an arterial pH of less than 7.25 with a partial pressure of arterial carbon dioxide (PaCO 2) of more than 60 mm Hg (8.0 kPa), metabolic acidosis not responsive to treatment, or treatment with more than a 60% concentration of oxygen. Infants receiving CPAP could be treated with surfactant only after intubation. Criteria for extubation were not specified. Surfactant treatment, ventilation settings, and extubation and reintubation criteria were not mandated and followed local protocols.

Primary and Secondary Outcomes The primary outcome was death or bronchopulmonary dysplasia (defined as the need for oxygen treatment at 36 weeks' gestational age). Prespecified secondary outcomes were the incidence of intubation, reasons for intubation, the need for oxygen treatment at 28 days, the fraction of inspired oxygen (FIO 2) at 36 weeks' gestational age, the incidence of air leaks and intracranial hemorrhages, the duration of ventilation and CPAP, the number of days in the hospital, the number of days to regain birth weight, methylxanthine treatment, treatment with postnatal corticosteroids, and the dose of surfactant.

Data were collected on infants until their death or discharge from hospital. The FIO 2 at 36 weeks' gestational age was recorded for infants treated with oxygen or calculated for infants treated with oxygen by nasal cannula at various flow rates and concentrations. Statistical Analysis On the basis of data from the Australian and New Zealand Neonatal Network for 1997 and 1998, we estimated that the rate of the primary outcome for all infants born at 25-to-28-weeks' gestation was 43%. We anticipated a lower rate of bronchopulmonary dysplasia among the infants in our study, since the need for antenatal consent excluded infants who were born outside a hospital, who required urgent delivery, or who were so ill that they required immediate intubation at birth. We estimated that the rate of death or bronchopulmonary dysplasia in infants eligible for the trial would be 30%. For a reduction of one third in this rate (to 20%), 600 infants were needed with a two-tailed type I error rate of 0.05 and a power of 80%. The analysis was performed according to the intention-to-treat principle.

Odds ratios with 95% confidence intervals and chi-square tests were used to compare proportions between the two study groups for the main dichotomous outcomes. Other dichotomous outcomes were compared with the use of Fisher's exact test because some outcomes were rare. All reported P values are two-sided.

The Wilcoxon rank-sum test was used to compare continuous outcomes with highly skewed distribution. For the main dichotomous outcomes, adjusted odds ratios and confidence intervals were also estimated with the use of multivariable logistic regression in order to control for potentially confounding effects of center, sex, gestational age, maternal use of antenatal corticosteroids, and multiple births. The analysis for the primary outcome was repeated with the use of the method of generalized estimating equations to account for correlation of outcomes between infants who were part of the same multiple birth, but results were substantially unaffected and are not reported. All analyses were performed with the use of Stata statistical software, version 9.2 (StataCorp). Results The numbers of infants who were eligible for the study, who were not enrolled or ineligible, and who were randomly assigned to receive nasal CPAP or intubation and ventilation are shown in Figure 1 Enrollment and Outcomes.. A total of 610 infants were enrolled between April 27, 1999, and March 23, 2006: 329 in Australia and New Zealand, 91 in the United States and Canada, and 190 in Europe.

The demographic and clinical characteristics at randomization were similar in the two groups ( Table 1 Baseline Demographic and Clinical Characteristics of the Patients. The unadjusted odds ratio for the primary outcome of death or oxygen treatment at 36 weeks' gestation comparing the CPAP group with the intubation group was 0.80 (95% confidence interval [CI], 0.58 to 1.12; P=0.19) ( Table 2 Death or Need for Oxygen Treatment or Respiratory Support at 36 Weeks' Gestational Age, According to Gestational Age at Birth. The unadjusted reduction in absolute risk was 5% (95% CI, –3 to 13). The comparison was not substantially changed by adjustment with the use of logistic regression, as described. The addition of respiratory support (treatment with CPAP or intubation and ventilation) at 36 weeks' gestational age to the outcome definition made little difference to the estimated effect. For the gestational-age subgroups, the odds ratio for the primary outcome was 0.99 for the group born at 25 or 26 weeks' gestation and 0.72 for the group born at 27 or 28 weeks' gestation in favor of the CPAP group but with no evidence for a true difference in effect between strata (P=0.37 for interaction).

There was no significant difference in mortality between the two groups, whether considered as a whole or within the age subgroups; most of the difference between the groups was in the need for oxygen treatment. At 36 weeks' gestational age, the majority of surviving infants in both groups were treated with no or very little supplemental oxygen. The 75th and 90th percentiles for the inspired oxygen concentration were 22% and 27%, respectively, for the intubation group, as compared with 21% and 28%, respectively, for the CPAP group. At 36 weeks' gestational age, an oxygen concentration of 30% or more was received by only 8.8% of the intubation group and 9.4% of the CPAP group (P=0.80), and only 1.3% of the CPAP group and 1.4% of the intubation group received either ventilation or CPAP. At 28 days of age, the unadjusted odds ratio for death or need for oxygen treatment was 0.63 (95% CI, 0.46 to 0.88; P=0.006) in favor of the CPAP group ( Table 3 Death or Need for Oxygen Treatment or Respiratory Support at 28 Days of Age, According to Gestational Age at Birth. This result was not greatly altered by adjustment for the above-mentioned covariates (adjusted odds ratio, 0.59; 95% CI, 0.41 to 0.85; P=0.005). The addition of respiratory support at 28 days to this outcome did little to alter the effect.

For the gestational-age strata, the unadjusted odds ratios were similar: for infants born at 25 or 26 weeks' gestation, 0.54 (95% CI, 0.27 to 1.08), and for those born at 27 or 28 weeks' gestation, 0.65 (95% CI, 0.44 to 0.96). The 50th, 75th, and 90th percentiles for the inspired oxygen concentration at 28 days were 23%, 29%, and 39%, respectively, for the intubation group and 21%, 25%, and 37%, respectively, for the CPAP group. Detailed data were collected during the first 5 days of life.

The intubation rate for the CPAP group was 46%, with a rate of 55% for infants born at 25 or 26 weeks' gestation and 40% for those born at 27 or 28 weeks' gestation. The median time for intubation was 6.6 hours (interquartile range, 2.2 to 19. Sniper Elite 3 Crack Reloaded Only. 3). The reasons for intubation were as follows: a FIO 2 of 0.60 or more (53% of infants), a PaCO 2 of more than 60 mm Hg (8.0 kPa) (41%), apneic episodes (38%), or metabolic acidosis unresponsive to treatment (21%); some infants had multiple reasons for intubation.

Another 39 patients in the CPAP group (12.7%) were intubated after 5 days of age. The median daily FIO 2 was approximately 0.21 in both groups during the first 5 days.

After day 3, fewer than half the infants in both groups were undergoing ventilation. The lowest and highest PaCO 2 levels were similar in both groups during the first 5 days. Other secondary outcomes are shown in Table 4 Comparison of Secondary Outcomes..

The use of surfactant was halved in the CPAP group, as compared with the intubation group. In the CPAP group, the incidence of pneumothorax was significantly increased, with a similar difference between both gestational-age subgroups in the two study groups. There were 28 pneumothoraxes in the CPAP group, with 36% detected on day 0, 43% on day 1, and 18% on day 3. However, this increase did not translate into a need for more respiratory support in the CPAP group. Indeed, days of ventilation were significantly reduced. There was weak evidence of fewer days of supplemental oxygen in the CPAP group (P=0.07).

There were no other substantial differences between the groups for other secondary outcomes, nor was there evidence that differences between study groups varied according to gestational-age subgroup. Discussion There was no statistical evidence of a difference in the combined outcome of death or bronchopulmonary dysplasia at 36 weeks' gestational age between infants who were assigned to receive early nasal CPAP and those who were assigned to receive intubation. However, at 36 weeks' gestational age, only 9% of infants in each group of survivors were receiving an oxygen concentration of 30% or more. The benefits of CPAP included a lower risk of the combined outcome of death or the need for oxygen therapy at 28 days and fewer days of assisted ventilation. A side effect of CPAP was an increase in the number of pneumothoraxes. Overall, starting early CPAP treatment in very preterm infants was not detrimental.

We randomly assigned infants to study groups after birth rather than antenatally to avoid inappropriate enrollment of infants with apnea in the CPAP group. This procedure reflected clinical practice in which the type of respiratory treatment is determined after observation in the minutes after birth.

The use of surfactant has become standard treatment for very preterm infants. However, in these randomized trials of surfactant, infants were electively intubated and rarely received early CPAP; in addition, few of the infants had received antenatal corticosteroid treatment.

At the time our trial began, there was increasing observational evidence that very preterm infants who were treated with early CPAP did not require either ventilation or the use of surfactant. We considered that early CPAP needed a randomized trial to define the effects. Even though only half the infants in the CPAP group received surfactant, there was no difference in FIO 2 or maximum PaCO 2 between the study groups during the first 5 days. Infants in the CPAP group required a significantly lower rate of oxygen treatment at 28 days and underwent fewer days of ventilation than did infants in the intubation group, even though the rate of pneumothorax was higher in the CPAP group. These findings suggest that it is possible to initiate CPAP in infants of 25-to-28-weeks' gestation and treat them with surfactant only if they require ventilation.

This conclusion is consistent with that of the study by Ammari et al. Regarding one hospital's experience with early CPAP. Ammari et al. Showed that 76% of infants weighing less than 1251 g and 50% of those weighing less than 751 g did not need to undergo ventilation. In our study, the intubation rate for the CPAP group was determined by the preset criteria for intubation. Trials have randomly assigned infants to receive elective intubation, followed by treatment with surfactant and then extubation to receive CPAP, although this regimen was not beneficial in all the trials. The intubation of very preterm infants can be difficult and may destabilize an infant's condition, a fact that prompted our investigation into whether it was appropriate to avoid intubation.

However, in our study, infants who were intubated were eligible for surfactant use, according to local protocols. The results of our trial corroborate those of Thomson and Escobedo et al. And do not encourage intubation specifically for the use of surfactant for infants in stable condition who are treated with CPAP, although further randomized trials are needed to compare that technique with CPAP. Our finding that infants in the CPAP group had more pneumothoraxes reflects the results of other studies. Of the infants with a pneumothorax, 96% underwent ventilation. The airway pressure when the pneumothorax was diagnosed was not recorded.

The median CPAP pressure on admission was 8 cm of water for infants in whom a pneumothorax developed as well as for those in whom a pneumothorax did not develop. If the pneumothoraxes were associated with the CPAP pressure, it is curious that the incidence was lower in the intubation group, which had higher peak and mean airway pressures. Surfactant treatment has been associated with a reduction in the rate of pneumothorax. An increased rate of pneumothorax may be a concern because past evidence has suggested that such an increase was associated with increased morbidity.

However, in our trial, there was no significant increase in the rate of death, grade 3 and 4 intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, or other adverse outcomes. In addition, the FIO 2 and maximum PaCO 2 in the first 5 days did not differ significantly between the study groups. A CPAP of 8 cm of water was used because a distending pressure is important for maintaining functional residual capacity and for improving lung compliance and oxygenation, and 8 cm of water had been shown to be more effective than a lower pressure.

Other studies have used pressures of up to 10 cm of water, and Gregory et al. Used a pressure of up to 12 mm Hg. Data from the first 5 days show that both study groups had relatively good lung function, with a median FIO 2 close to 0.21; the majority of infants in the intubation group were extubated within 3 days, and the median highest and lowest levels of PaCO 2 were within the normal range. This good early lung function may be one reason why the study showed a smaller difference than expected between the two groups in the primary outcome. Our study does not help to identify infants at birth who if treated with CPAP will subsequently require intubation and ventilation. However, it does suggest that starting respiratory support with CPAP does not adversely affect infants even if up to half of them subsequently undergo ventilation, some because of a pneumothorax. Our study has several limitations.

First, since the randomized treatment was not masked, the resuscitation and subsequent care may have been biased. Second, the consent and enrollment process meant that the infants did not represent all infants born at these gestational ages. Since antenatal consent had to be obtained, there was a lower incidence of acute or serious antenatal complications, and most mothers received antenatal corticosteroids. Also, sick infants who required immediate intubation were excluded. Third, even though more than 600 infants were enrolled, rates of uncommon outcomes were imprecisely estimated.

There was a significant imbalance between the groups in the Apgar score at 5 minutes (median score, 9 in the CPAP group and 8 in the intubation group), indicating that infants in both groups were in good condition although those in the CPAP group were rated slightly higher. The randomized treatment was started at the same time, so the Apgar scores may have been affected by the treatment at that time. In conclusion, infants who were born at 25-to-28-weeks' gestation and were breathing spontaneously were treated with CPAP shortly after birth. Half were subsequently intubated. Infants in the CPAP group had a better outcome at 28 days than did those in the intubation group; the two groups had a similar outcome at 36 weeks' gestational age, but there was an increased incidence of pneumothorax in the CPAP group.

Supported by a grant (148002) from the Australian National Health and Medical Research Council. Morley reports being a member of the Australian Resuscitation Council, serving as a coeditor of the Australian Neonatal Resuscitation Guidelines, and serving on the International Liaison Committee on Resuscitation and assisting with the 2005 International Guidelines for Neonatal Resuscitation. No other potential conflict of interest relevant to this article was reported. We thank Katherine Smith, statistician at the Clinical Epidemiology and Biostatistics Unit, Murdoch Children's Research Institute, Melbourne, for performing the main statistical analysis. References • 1 Hansen TN, Corbet A. Disorders of transition. In: Taeusch HW, Ballard RA, eds.

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Is chronic lung disease in low birthweight infants preventable? A survey of eight centers. Pediatrics 1987;79:26-30 • 13 Jonsson B, Katz-Salamon M, Faxelius G, Broberger U, Lagercrantz H. Neonatal care of very low birth weight infants in special-care units and neonatal intensive care units in Stockholm: early nasal continuous positive airway pressure versus mechanical ventilation: gains and losses.

Acta Paediatr Suppl 1997;419:4-10 • 14 Kamper J, Wulff K, Larsen C, Lindequist S. Early treatment with nasal continuous positive airway pressure in very low birth weight infants. Acta Paediatr 1993;82:193-197 • 15 Jacobsen T, Gronvall J, Petersen S, Andersen GE.

“Minitouch” treatment of very low-birth-weight infants. Acta Paediatr 1993;82:934-938 • 16 Gittermann MK, Fusch C, Gittermann AR, Regazzoni BM, Moessinger AC. Early nasal continuous positive airway pressure treatment reduces the need for intubation in very low birth weight infants. Eur J Pediatr 1997;156:384-388 • 17 Poets CF, Sens B. Changes in intubation rates and outcome of very low birth weight infants: a population-based study. Pediatrics 1996;98:24-27 • 18 Millet V, Lacroze V, Bartoli JM, Samperiz S, Leclaire M, Unal D.

Early continuous positive pressure in the labor room. Arch Pediatr 1997;4:15-20 • 19 Joris N, Sudre P, Moessinger A. Early application of CPAP in newborns with gestational age below 34 weeks lowers intubation rate and shortens oxygen therapy without altering mortality and morbidity. Schweiz Med Wochenschr 2000;130:1887-1893 • 20 De Klerk AM, De Klerk RK. Nasal continuous positive airway pressure and outcomes of preterm infants. J Paediatr Child Health 2001;37:161-167.