Postnatal Conditions Research Articles

Predicting Older Age Mortality Trends

Improving early prenatal and postnatal conditions account for at least 16% to 17% of the decline in ten-year mortality rates of 60–79-year-olds between 1900 and 1960–1980. Historical trends in early prenatal and postnatal conditions imply that while the baby-boom cohort may be particularly long-lived compared to past cohorts, mortality rates may not fall as steeply for the cohorts born after 1955 as for earlier cohorts. (JEL: J15, N31)

Predicting Older Age Mortality Trends

Improving early prenatal and postnatal conditions account for at least 16 to 17 percent of the decline in ten year mortality rates of 60-79 year olds between 1900 and 1960-80. Historical trends in early prenatal and postnatal conditions imply that while the baby-boom cohort may be particularly long-lived compared to past cohorts, mortality rates may not fall as steeply for the cohorts born after 1955 as for earlier cohorts.

Lower fetal status of docosahexaenoic acid, arachidonic acid and essential fatty acids is associated with less favorable neonatal neurological condition

Long-chain polyunsaturated fatty acids, notably arachidonic (AA) and docosahexaenoic (DHA) acids are abundant in brain and may be conditionally essential in fetal life. We investigated umbilical artery (UA) and vein (UV) fatty acid compositions and early neonatal neurological condition in 317 term infants. Neurological condition was summarized as a clinical classification and a ‘neurological optimality score’ (NOS). Neurologically abnormal infants ( n = 27 ) had lower UV DHA and essential fatty acid (EFA) status. NOS correlated positively with AA (UV), and EFA (UV) and DHA status (UV and UA) and negatively with 18:2 ω6 and ω9 (UV), and 20:3 ω9, ω7 and C18 trans fatty acids (UV and UA). UV DHA, AA, saturated fatty acids, gestational age and obstetrical optimality score explained 16.2% of the NOS variance. Early postnatal neurological condition seems negatively influenced by lower fetal DHA, AA and EFA status. C18 trans fatty acids and 18:2 ω6 may exert negative effects by impairment of LCP status.

Postnatal maturation of cortical serotonin lateral asymmetry in gerbils is vulnerable to both environmental and pharmacological epigenetic challenges

Long-term effects of postnatal differential rearing conditions and/or early methamphetamine (MA) application on serotonin (5-HT) fibre density were investigated in several cortical areas of both hemispheres of gerbils. The aim of this study was twofold: (1) Is the 5-HT fibre innervation of the cerebral cortex lateralised, and (2) if so, do postnatal environmental conditions and/or an early drug challenge interfere with development of 5-HT cerebral asymmetries? For that purpose, male gerbils were reared either under semi-natural or restricted environmental and social conditions, under both conditions once (on postnatal day 14) being treated with either a single dose of MA (50 mg/kg, i.p.) or saline. On postnatal day 110, 5-HT fibres were immunohistochemically stained and innervation densities quantified in prefrontal cortex, insular cortex, frontal cortex, parietal cortex, and entorhinal cortex. It was found that (1) 5-HT innervation in the cerebral cortex was clearly lateralised; (2) direction and extent of this asymmetry were not uniformly distributed over the different areas investigated; (3) both early methamphetamine challenge and rearing condition differentially interfered with adult 5-HT cerebral asymmetry; (4) combining MA challenge with subsequent restricted rearing tended to reverse the effects of MA on 5-HT cerebral asymmetry in some of the cortical areas investigated; and (5) significant responses in 5-HT cerebral asymmetry only occurred in prefrontal and entorhinal association cortices. The present findings suggest that the ontogenesis of cortical laterality is influenced by epigenetic factors and that disturbances of the postnatal maturation of lateralised functions may be associated with certain psychopathological behaviours.

P1-312 Postnatal stress or enrichment conditions can influence the prenatal effects on cognitive ability, cell proliferation, and synaptic protein expression

P1-312 Postnatal stress or enrichment conditions can influence the prenatal effects on cognitive ability, cell proliferation, and synaptic protein expression

Maternal investment affects offspring phenotypic plasticity in a viviparous cockroach.

Maternal effects, crossgenerational influences of the mother's phenotype on phenotypic variation in offspring, can profoundly influence the fitness of offspring. In insects especially, social interactions during larval development also can alter life-history traits. To date, however, no experimental design, to our knowledge, has manipulated the prenatal and postnatal environments independently to investigate their interaction. We report here that the degree of maternal nutrient investment in developing embryos of the viviparous cockroach Diploptera punctata influences how quickly neonate males become adults and how large they are at adulthood. An offspring's probability of reaching adulthood in fewer than four molts increased with birth weight: the heavier neonates were, consequently, more likely to become smaller adults. Social interaction also affected nymphal development and adult size. Nymphs reared in pairs molted fewer times than solitary nymphs and, thus, became smaller adults. The social effect on developmental trajectory was, however, eliminated by experimentally increasing the level of maternal nutrient investment per offspring, which was accomplished by removing one of the female's paired ovaries (allometric engineering). We conclude that a particular prenatal environment can result in different offspring phenotypes under different postnatal social conditions. By investing more in each offspring, however, D. punctata mothers, because they are viviparous, are able to produce broods with environmentally (socially) independent phenotypes.

Severe epilepsy with multiple independent spike foci.

Severe epilepsy with multiple independent spike foci is an electroclinical entity with the following characteristics: (1) EEG showing multiple independent spike foci (three or more foci in both hemisphere, i.e., at least one in each hemisphere) and diffuse slowing of the background activity, (2) very frequent multiple types of seizures but mainly generalized minor seizures, (3) frequent association with mental retardation and neurologic abnormalities, (4) underlying causes of various nonspecific prenatal, perinatal, and postnatal cerebral conditions, and (5) poor prognoses for seizures and psychomotor development. It represents a diffuse encephalopathy with mutual transition between other age-dependent epileptic encephalopathies. This electroclinical condition may be appropriately named Markand-Blume-Ohtahara syndrome, after Markand and Blume, who initially described in detail the EEG pattern of multifocal spike discharges with its major clinical correlates, and Ohtahara, who extensively studied the group of patients with both clinical and EEG characteristics and proposed the concept of severe epilepsy with multiple independent spike foci, classifying it as one type of generalized epilepsy.

Circadian Rhythms in Infants

After completing this article, readers should be able to: 1. Describe how circadian rhythms are generated. 2. Describe how lighting influences the circadian system. 3. Delineate the period during which the origin of circadian rhythms develops. 4. Describe the relationship between maternal circadian rhythms and the development of circadian rhythms in infants. 5. Characterize the potential sequelae of impaired fetal and early neonatal circadian rhythms related to sleep patterns. 6. Describe beneficial lighting patterns for preterm infants in the neonatal intensive care nursery. Circadian rhythms are endogenously generated rhythms that have a period length of about 24 hours. Evidence gathered over the past decade indicates that the circadian timing system develops prenatally, with the suprachiasmatic nuclei (SCN) in the anterior hypothalamus, the site of a circadian clock, present by mid-gestation in primates. Recent evidence also shows that the circadian system of primate infants is responsive to light at very early stages (as early as 25 to 28 weeks’ gestation in humans) and that low-intensity lighting can regulate the developing clock. After birth, circadian system outputs mature progressively, with rhythms in sleep-wake cycles, body temperature, and hormone production generally developing between 1 and 3 months of age. The importance of light in regulation of circadian rhythm in infants is highlighted by the early establishment of rest-activity patterns that are in phase with the 24-hour light-dark cycle in preterm infants exposed to low-intensity cycled lighting. With the continued elucidation of circadian system development and influences on human physiology and illness, it is anticipated that consideration of circadian biology will become an increasingly important component of neonatal care. ### The Circadian Timing System Notable examples of circadian rhythms include the sleep-wake cycle and daily rhythms in body temperature and hormone production. Circadian rhythms are also involved in the pathogenesis of illnesses, such as reactive airway disease (eg, asthma) and myocardial infarction. The system responsible …

Environmental and genetic background of tiptoe-initiating behaviour in the dwarfspider Erigone atra

Ballooning is a widespread behavioural trait in invertebrates, which enhances passive aerial dispersal. We investigated the influence of common lineage (family effect) and postnatal environmental conditions on latency to initiate preballooning tiptoe behaviour (ballooning latency) in the dwarfspider Erigone atra (Blackwall, 1841). The ballooning latency of individual spiders was tested in a specially designed test chamber. In a 3-week experiment, in which the spiders were fed only during the first day of each week, ballooning latency had low repeatability at weekly intervals. Ballooning latency declined with increasing food deprivation during the first week but not during the second and the third weeks. At intervals of less than 1h, however, ballooning latency showed high repeatability. We also investigated whether maternal and postnatal environmental conditions (i.e. during juvenile development) influence phenotypic variation in ballooning latency. We reared offspring of several families under two feeding and two temperature conditions. Environmental conditions explained more variation in ballooning latency than family. Ballooning latency was lower in spiders reared at 20°C than in those reared at 15°C. In addition, spiderlings fed four prey per 3 days were faster ballooners than those fed only four prey per week. An interaction between factors was present, indicating the existence of different reaction norms between the two environmental conditions. The expression of ballooning latency behaviour thus strongly depends on current nutrition, feeding history and the feeding and temperature conditions during juvenile development. Copyright 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour.

Ultrasonographic prediction of clinical pulmonary hypoplasia: measurement of the chest/trunk-length ratio in fetuses

Pulmonary hypoplasia is involved in patients with various surgical diseases. The aim of this study was to evaluate the clinical usefulness of measurement of the chest/trunk-length ratio (C/T) for predicting pulmonary hypoplasia in patients with congenital anomalies, with the exception of mass-like lesions in the thorax such as diaphragmatic hernia and cystic lung diseases. For measurement of C/T on fetal ultrasound, the sagittal section of the body trunk, including the spine, was analyzed. C/T was calculated as the chest length, defined from the top of the thorax to the top of the diaphragm, divided by the trunk length, defined from the top of the thorax to the bottom of the urinary bladder. From 1986 to 2000, measurements of C/T were undertaken in 49 healthy fetuses from 17 to 37 weeks of gestation and 98 fetuses with congenital anomalies, with the exception of intra-thoracic mass lesions, omphalocele, and fetal hydrops. Pulmonary hypoplasia was clinically assessed by the following criteria: (1) a lung-to-birth-weight ratio of 0.012 or less; (2) patients who required high-frequency oscillatory ventilation with mean airway pressure of 15 cmH(2)O or more with pure oxygen and/or who died presenting respiratory failure without evidences of meconium aspiration, congenital pneumonia, sepsis or hyaline membrane disease. For a predicting value for pulmonary hypoplasia to be obtained, sensitivity, specificity, positive predictive value and negative predictive value were quoted between C/T in patients with pulmonary hypoplasia and those without pulmonary hypoplasia. Healthy fetuses revealed the mean value as 0.38+/-0.03, with no significant change after 20 weeks of gestation. Pulmonary hypoplasia was assessed in 25 fetuses with urethral atresia and stenosis, renal agenesis, polycystic kidney, cloacal anomalies, diaphragmatic eventration, bronchopulmonary foregut malformation, chest deformity, meconium peritonitis and sacrococcygeal teratoma. As a predicting value for pulmonary hypoplasia, 0.32 or less of the maximum value of C/T indicated good accuracy, with a sensitivity of 92.0%, specificity of 95.9%, positive predictive value of 88.5% and negative predictive value of 97.2%. Ultrasonic measurement of C/T is useful in predicting postnatal respiratory conditions with regard to pulmonary hypoplasia.

Pathophysiology of autism: current opinions.

Research on the neurochemical aspects of the pathophysiology of autism is still increasing and publications are abundant. In this paper we reviewed significant data from the last decade and recent research results from our center. We focused on molecules influencing the central nervous system (CNS) and consecutively responsible for typical autistic behavior. We highlighted the mutual relationship between the serotonergic, immunological and endocrinological system and the interaction of these three pivotal systems with predisposing (genetic)and external (pre-, peri- and postnatal) conditions and xenobiotics. We stressed the influence of age, pubertal stage, sex, race and IQ on biological data. There is growing evidence that the complexity and variability of those interactions might be responsible for the heterogeneity of behavioral phenotypes and biological findings in Autism. Genetic, neuroanatomical and neurophysiological data were mentioned according their relevance to neurochemical opinions.

Early life stress and inherited variation in monkey hippocampal volumes.

Opportunities for research on the causes and consequences of stress-related hippocampal atrophy are limited in human psychiatric disorders. Therefore, this longitudinal study investigated early life stress and inherited variation in monkey hippocampal volumes. Paternal half-siblings raised apart from one another by different mothers in the absence of fathers were randomized to 1 of 3 postnatal conditions that disrupted diverse aspects of early maternal care (n = 13 monkeys per condition). These conditions were previously shown to produce differences in social behavior, emotional reactivity, and neuroendocrine stress physiology. Hippocampal volumes were subsequently determined in adulthood by high-resolution magnetic resonance imaging. Adult hippocampal volumes did not differ with respect to the stressful postnatal conditions. Based on paternal half-sibling effects, the estimated proportion of genetic variance, ie, heritability, was 54% for hippocampal size. Paternal half-siblings with small adult hippocampal volumes responded to the removal of all mothers after weaning with initially larger relative increases in cortisol levels. Plasma cortisol levels 3 and 7 days later, and measures of cortisol-negative feedback in adulthood were not, however, correlated with hippocampal size. In humans with mood and anxiety disorders, small hippocampal volumes have been taken as evidence that excessive stress levels of cortisol induce hippocampal volume loss. Results from this study of monkeys suggest that small hippocampi also reflect an inherited characteristic of the brain. Genetically informed clinical studies should assess whether inherited variation in hippocampal morphology contributes to excessive stress levels of cortisol through diminished neuroendocrine regulation.

The impact of corticosteroids on the developing animal.

Infants are subjected to both endogenous and exogenous corticosteroids in the pre- and postnatal periods. Stress to the mother before birth, or to the child postpartum, can give rise to high, chronic endogenous corticosteroid levels caused by activation of the hypothalamic-pituitary-adrenal (HPA) axis. Physician-administered exogenous corticosteroids are also used in the management of a wide spectrum of pre- and postnatal conditions. The long-term effects of corticosteroids in developing humans are not well known. Studies in animals, however, indicate that both natural stress and exogenous corticosteroids can have long-lasting and deleterious effects on the body, brain, behavior, and hypothalamic-pituitary-adrenal axis of developing infants. These data suggest that exogenous corticosteroids should be administered with caution, after careful benefit/risk analyses, and that, as far as possible, the developing brain should be protected against the effects of pre- and postnatal stress.

Lethal Pulmonary Hypoplasia After In-Utero Myelomeningocele Repair

In Brief BACKGROUND In-utero surgical repair of fetal myelomeningocele has been performed as a means to improve the postnatal condition of affected infants. CASE A nulliparous woman underwent in-utero surgical repair of a fetal lumbosacral myelomeningocele at 24 weeks' gestation. Her postoperative convalescence was complicated by pulmonary edema, abdominal pain, chronic oligohydramnios, and preterm labor. The infant was delivered by cesarean at 33 weeks' gestation, but expired from respiratory distress caused by pulmonary hypoplasia at 9 hours of age. CONCLUSION Until the benefits of in-utero repair of fetal myelomeningoceles are determined by well-controlled clinical trials, this technique remains investigational. Physicians and their patients who are considering this procedure must be fully aware of the potential risks that can occur. Lethal pulmonary hypoplasia was associated with prolonged oligohydramnios after in-utero myelomeningocele repair.

Lethal pulmonary hypoplasia after in-utero myelomeningocele repair

BACKGROUND: In-utero surgical repair of fetal myelomeningocele has been performed as a means to improve the postnatal condition of affected infants. CASE: A nulliparous woman underwent in-utero surgical repair of a fetal lumbosacral myelomeningocele at 24 weeks’ gestation. Her postoperative convalescence was complicated by pulmonary edema, abdominal pain, chronic oligohydramnios, and preterm labor. The infant was delivered by cesarean at 33 weeks’ gestation, but expired from respiratory distress caused by pulmonary hypoplasia at 9 hours of age. CONCLUSION: Until the benefits of in-utero repair of fetal myelomeningoceles are determined by well-controlled clinical trials, this technique remains investigational. Physicians and their patients who are considering this procedure must be fully aware of the potential risks that can occur.

Climate and population density induce long‐term cohort variation in a northern ungulate

Summary Density‐dependent and climatic conditions experienced by individuals before and after birth differ considerably between cohorts. Such early environmental variability has the potential to create persistent fitness differences among cohorts. Here we test the hypothesis that conditions experienced by individuals in their early development will have long‐term effects on their life history traits. We approached this by analysing and contrasting the effects of climate (the North Atlantic Oscillation, NAO) and population density at year of birth on cohort birth weight, birth date, litter size, age of maturity, survival and fecundity of Soay sheep, Ovies aries L., ewes in the population on the island of Hirta, St Kilda, Scotland. Significant intercohort variations were found in life history traits. Cohorts born after warm, wet and windy (high NAO) winters were lighter at birth, born earlier, less likely to have a twin and matured later than cohorts born following cold and dry (low NAO) winters. High population densities in the winter preceding birth also had a negative effect on birth weight, birth date and litter size, whereas high postnatal densities delayed age of first reproduction. High NAO winters preceding birth depressed juvenile survival but increased adult survival and fecundity. The negative influence of high NAO winters on juvenile survival is likely to be related to mothers’ compromised physical condition while the cohort is in utero, whereas the positive influence on adult survival and fecundity may relate to the improved postnatal forage conditions following high NAO winters. High pre‐ and postnatal population densities decreased juvenile (neonatal, yearling) and adult (2–4 years) survivorship but had no significant effect fecundity.

Fetal and Infantile Alcohol‐Mediated Associative Learning in the Rat

Infant rats express conditioned responses to an odor experienced prenatally as a chemosensory cue associated with moderate alcohol intoxication. This study examined postnatal intake of a chemosensory cue (cineole) that had been paired with alcohol's unconditioned effects. It also tested the interaction between prenatal association and postnatal conditioning with cineole and alcohol. Pregnant female rats intubated with cineole were given ethanol (EtOH).25 or 4.0 hr later. Other groups received only water or water paired with ethanol. During postnatal day 15 (PD15), infant consumption of cineole solution was assessed. After the cineole drinking test, pups were intubated with EtOH or water to assess infant conditioning. On PD16, all pups were tested for mouthing to milk alone or to a milk-cineole solution. Statistical analysis confirmed fetal associative conditioning attributable to the unconditioned effects of prenatal alcohol. Fetuses given explicit pairings of cineole and alcohol ingested less cineole on PD15 than control fetuses given a 4-hr interval between cineole and alcohol. On PD16, consumption of cineole was significantly increased by prenatal exposure to cineole. Teratogenic effects of this dose of prenatal alcohol did not affect postnatal associative or nonassociative behavior. Prenatal associative learning can be established through temporal contiguity between fetal chemosensory stimulation and alcohol's unconditioned properties. This associative memory survives to infancy and modulates intake patterns and behavioral reactivity to substances that were prenatally paired with alcohol intoxication.

THE CONTRIBUTION OF PHENOTYPIC PLASTICITY TO ADAPTATION IN LACERTA VIVIPARA

Correlation between intraspecific phenotypic variability and variation of environmental conditions could reflect adaptation. Different phenotypes may result from differential expression of a genotype in different environments (phenotypic plasticity) or from expression of different genotypes (genetic diversity). Populations of Lacerta vivipara exhibit larger adult body length, lower age at maturity, higher fecundity, and smaller neonatal size in humid habitats compared to dry habitats. We conducted reciprocal transplants of juvenile L. vivipara to test for the genetic or plastic origin of this variation. We captured gravid females from four populations that differed in the relative humidity of their habitats, and during the last 2 to 4 weeks of gestation, we manipulated heat and water availability under laboratory conditions. Juveniles were released into the different populations and families were divided to compare growth rate and survival of half-sibs in two environments. Growth rate and survival were assessed using capture-recapture techniques. Growth rate was plastic in response to postnatal conditions and did not differ between populations of origin. Survival differed between populations of origin, partially because of differences in neonatal body length. The response of juvenile body length and body condition to selection in the different habitats was affected by the population of origin. This result cannot be simply interpreted in terms of adaptation; however, phenotypic plasticity of fecundity or juvenile size most probably resulted in adaptive reproductive strategies. Adaptation to the habitat by means of genetic specialization was not detected. Further investigation is needed to discriminate between genetic and long-term maternal effects.

Differential environment alters ontogeny of dopamine innervation of the orbital prefrontal cortex in gerbils

In the present study, the influence of postnatal environmental conditions on the structural ontogeny of the orbital prefrontal cortex of adult gerbils (Meriones unguiculatus) was examined. The animals were bred and reared either isolated in standard laboratory cages or grouped in an object-filled environment. At the age of postnatal day 90, dopamine fibers were stained immunocytochemically and innervation density was determined in the orbital prefrontal cortex. By comparison, restricted rearing produced a restraint of the subsequent maturation of orbital prefrontal dopamine innervation, leading to adult fiber densities that were approximately 38% below those in seminaturally reared gerbils. Results are discussed in terms of activity-dependent postnatal maturation of the cortex and adaptive neuroplasticity with regard to previously published data concerning diminished dopamine innervation in the medial prefrontal cortex (Winterfeld et al. [1998] J. Neurosci. Res. 63:209–213, 2001. © 2001 Wiley-Liss, Inc.

Differential environment alters ontogeny of dopamine innervation of the orbital prefrontal cortex in gerbils.

In the present study, the influence of postnatal environmental conditions on the structural ontogeny of the orbital prefrontal cortex of adult gerbils (Meriones unguiculatus) was examined. The animals were bred and reared either isolated in standard laboratory cages or grouped in an object-filled environment. At the age of postnatal day 90, dopamine fibers were stained immunocytochemically and innervation density was determined in the orbital prefrontal cortex. By comparison, restricted rearing produced a restraint of the subsequent maturation of orbital prefrontal dopamine innervation, leading to adult fiber densities that were approximately 38% below those in seminaturally reared gerbils. Results are discussed in terms of activity-dependent postnatal maturation of the cortex and adaptive neuroplasticity with regard to previously published data concerning diminished dopamine innervation in the medial prefrontal cortex (Winterfeld et al. [1998]