Premature Research Articles

Immunoglobulin-A Profile in Breast Milk from Mothers Delivering Full Term and Preterm Infants

Recent advances in the care of low-birth-weight and preterm neonates have stimulated research into the best dietetic program to improve their survival and short/long term outcome. Some components of human milk that cannot be included in artificial formulas may be critical for survival. Of these, immunoglobulins are important, and in particular secretory immunoglobulins A (sIgA). The concentration of secretory IgA was measured by immunoblotting (an immunoelectrophoretic technique having high specificity and reliability) in milk from mothers delivering at term (TM) or prematurely (PM). In both groups, IgA concentrations were high very early on but quickly decreased during the first week of lactation. The early IgA mean concentration was higher in PM than in TM but, because of high variability in PM milk, the difference rarely reached statistical significance. This variability during lactation reflects the important role of human milk in supplying immunological factors to cope with the gastrointestinal absorption of high molecular weight proteins in the first days of life. Immunological protection is particularly critical for a preterm baby, so it is important to promote feeding with its own mothers milk if possible, paying strict attention to the timing of milk collection.

237 EXPRESSION OF THE GENES HSP 70.1, ZAR-1, AND MATER IN BOVINE OOCYTES SUBMITTED TO PREMATURATION AND/OR IN VITRO MATURATION

The present study aimed to assess the transcripts for the proteins that embryos require, histone 2a (H2a-FZ), heat shock 70 kDa protein 1A (HSP 70.1), zygote arrest 1 (ZAR-1), and maternal antigen (MATER), in bovine oocytes submitted to prematuration (PM) culture and/or in vitro maturation (IVM). Follicles (2–6 mm diameter) were aspirated from slaughterhouse-derived ovaries. Oocytes were selected and randomly distributed among treatments. For PM, oocytes were cultured 24 h in TCM-199 medium supplemented with 10 µm butyrolactone I, 0.2 mm pyruvate, and 10 µg mL–1 gentamicin (BGV group). Part of the prematured oocytes were washed and transferred to IVM culture (BMII group). For IVM, oocytes were cultured in TCM-199 supplemented with 10% FCS, 5.0 µg mL–1 LH, 0.5 µg mL–1 FSH, 0.2 mm pyruvate, and 10 µg mL–1 gentamicin for 22 h. As controls one group of oocytes was collected immediately after aspiration (GV group) and another group was matured in vitro (MII group) without undergoing prematuration. All cultures were carried out in 100-µL droplets of culture medium under mineral oil at 38.5�C and 5% CO2 in air. Oocytes from each treatment were denuded and frozen at 80�C (3 pools of 200 oocytes) in PBS with 0.1% polyvinyl alcohol (PVA) and 1 UI µL–1 RNase inhibitor. RNA was extracted using the RNeasy Protect Kit (Qiagen, S�o Paulo, Brazil) according to the manufacturer's instructions. The extracted RNA was used for reverse transcription by the enzyme Improm-II Reverse Transcriptase (Promega, Madison, WI, USA) according to the manufacturer's instructions. cDNA was produced in a thermocycler for 60 min at 42�C, followed by warming to 70�C for 15 min and cooling to 4�C for freezing at –20�C. Relative quantification of the transcripts for the genes H2a-FZ, HSP 70.1, ZAR-1, and MATER was performed by real-time PCR using the SYBR GREEN Kit (Applied Biosystems do Brasil, Sao Paulo, Brazil) according to manufacturer's instructions. Data were analyzed by the REST� software (Relative Expression Software Tool; Pfaffl et al. 2002 Nucl. Acids Res. 30, e36) 2005 BETA V1.9.9; a level of significance of 5% was considered to show differences among transcripts using H2a-FZ to normalize data. No differences were observed (P < 0.05) for the transcripts HSP 70.1, ZAR-1, and MATER, respectively, when comparing GV (1.0, 1.0, and 1.0), MII (0.37 � 0.1, 0.37 � 0.05, and 0.43 � 0.1), and GV with BGV (0.43 � 0.15, 0.54 � 0.2, and 0.33 � 0.25). However, a difference was detected (P < 0.05) between BGV (1.0, 1.0, and 1.0) and BMII (0.17 � 0.1, 0.13 � 0.05, and 0.3 � 0.2), but not between (P > 0.05) MII (1.0, 1.0, and 1.0) and BMII (0.52 � 0.25, 0.5 � 0.1, and 0.6 � 0.25) for transcripts HSP 70.1, ZAR-1, and MATER, respectively. A reduction in transcripts in group BMII may influence oocyte competence, reducing embryo development and/or quality.

Cholera Outbreaks and Ocean Climate

Rita R. Colwell Cholera Outbreaks and Ocean Climate W HAT I SHALL DO IN TH IS BRIEF PAPER, RATHER TH A N JUM P INTO THE ring w ith gloves to join th e debate on science and policy, is p u t a hum an face on one of the m ost serious issues we are discussing: the com plexity of clim ate change.' We need to understand very clearly that w hen one discusses, for example, clim ate and infectious disease, the problem is com plicated and the interactions involved are both m ultidisciplinary and interdisciplinary. The hum an perspective m ust be included if we are to com prehend fully the global effects of climate change. It would be useful to start not by belaboring points of conten­ tion but by indicating w here there is agreem ent. Everyone agrees that global w arm ing is occurring. Over the past few years, the highest average tem peratures in history have been recorded. No one argues that. The argum ent, of course, is w hether we are undergoing a natural cycle or anthropogenic-induced change. But, let us look at the fact th at the ocean surface annual tem peratures have increased. W arren W ashington speaks eloquently of his research at the National Center for A tm ospheric Research (NCAR) on th e dram atic changes such tem perature increases will invoke on sea surface levels (Washington, in press). My focus is on one aspect of global warming: hum an health and the w eather-related effects of clim ate change on infectious disease. The United States surgeon general’s report in 1950 declared the war social research Vol 73 : No 3 : Fall 2006 753 on infectious disease over because of the discoveries of m any power­ ful antibiotics. It was a prem ature declaration; infectious diseases are a moving target and rem ain very serious threats to the hum an race. Globally, acute respiratory infections, including pneum onia and influ­ enza (avian influenza is a loom ing threat), are the num ber one killer. However, for children under the age of five, diarrheal disease remains a m ajor killer, especially in developing countries. Cholera, a diarrheal disease, has been w ith us for a very long tim e, even being m entioned in ancient Sanskrit w ritings. A m edical textbook published in 1875 reported cholera to be a global pandem ic, consistently appearing in India, Bangladesh, Latin Am erica, and Africa. Today, cholera rem ains a serious problem . U ntil the nine­ teen th century, cholera was generally confined to the Indian subcon­ tinent, but it th en began to appear in Europe and the Americas as well. Since 1817, W estern m edical history describes seven global pandem ics o f cholera th a t have spread illness and death around the world. The second of these seven pandem ics reached the United States in 1832, traveling from New York to Philadelphia in a couple of weeks, and th en cases appeared along the A tlantic coast all the way to the Gulf of Mexico. In fact, W ashington, D.C. and New York, u n til 1900, saw frequent epidem ics of fevers, including typhoid, m alaria, and cholera. Cholera arose in epidem ic form in London in 1849, at a tim e w hen the germ theory of disease was being debated. John Snow, in that year, carried out the first published epidemiological study, charting cases of cholera in London. He concluded that the cholera cases clus­ tered around a well in central London w hen cholera was at its peak during the sum m er m onths. The epidemic abated in the September of 1849 but, as I will explain, the decline had to do w ith natural factors rather than the purported removal of the handle from the pum p by John Snow. In 1977, my cow orkers and I reported th at Vibrio cholerae, the causative agent of cholera, could be cultured from Chesapeake Bay 754 social research w ater samples. It was the first report of the isolation of the chol­ era vibrio from noncholera-endem ic geographical...

Aerobic and Lung Performance in Premature Children With and Without Chronic Lung Disease of Prematurity

This study intended to identify pulmonary and exercise-related effects of chronic lung disease of infancy (CLD) versus prematurity (PRE) without CLD in children 5 to 7 years old who were born prematurely (24-30 weeks of gestation) with very low and extremely low birthweight of 500 to 1500 g (VLBW, ELBW). Seventeen CLD and 14 PRE were compared with 24 term controls (CON). The premature children had no overt manifestations of a neuromuscular disease. Pulmonary function at rest and following exercise, and aerobic exercise performance were measured. Peak [latin capital V with dot above]O2 and maximal aerobic power were not different among the groups, but O2 uptake at a given mechanical power was higher in the CLD than in PRE and in CON (P < 0.05). At rest, forced vital capacity was significantly lower in CLD than in PRE (P < 0.05) and CON (P < 0.0005), and FEV1 and FEF25-75 were lower in CLD than CON (P < 0.0005 and P < 0.005, respectively). Exercise-induced bronchoconstriction (EIB) was more prevalent among the 2 premature groups (P < 0.05). Our children 5 to 7 years old born at VLBW or ELBW, with or without CLD, have some degree of pulmonary dysfunction at rest and following exercise and a higher prevalence of EIB with no reduction in maximal aerobic exercise performance. The findings suggest that the pulmonary limitations are associated with low birthweight even in the absence of CLD. The higher O2 uptake at a given mechanical power in the CLD group may cause early fatigability during prolonged exercise, even when aerobic performance is normal.

Birth prematurity determines prolonged autonomic nervous system immaturity

Because of its multiple involvement in physiological processes, autonomic nervous system (ANS) activity, a key regulator of homeostatic control, demonstrates a progressive increase during pregnancy. The profile of its maturation, mainly in the parasympathetic arm, in premature or full term infants, may help us to better understand its pathophysiological role. We prospectively evaluated ANS maturity in a group of 23 premature (PREM) infants at their theoretical term age and in 8 full term (FT) newborns. All recordings were registered close to the theoretical full term period (from 38 to 41 weeks) for the PREM group and during the first week of life for the FT newborns. Polygraphic recordings, EEG monitoring associated with visual clinical control, and Holter ECG, were performed simultaneously. ANS indices were then calculated during quiet sleep periods, using Wavelet transform of RR (beat to beat) intervals. High frequency components were found to be significantly lower in the PREM than in the FT group (p<0.05). Furthermore, at theoretical full term age, the greater the prematurity, the lower was parasympathetic activity. Because it is easy, monitoring of parasympathetic activity may help us to understand autonomic maturation and its clinical prognostic implications.

210 A 16-Year Study of Low Birth Weight Infants in China

Purpose: To compare the growth and neurodevelopment from birth to age 16 yrs of premature (PRE), small-for-gestational-age (SGA), and normal-birth-weight (NBW) infants born and raised in China.

94MEIOSIS INHIBITION OF BOVINE OOCYTES: EFFECTS ON SURVIVAL AFTER VITRIFICATION BY OPEN PULLED-STRAW METHOD

Mammalian oocytes remain one of the most difficult cell types to successfully cryopreserve. The in vitro-maturation protocols (IVM) have a large impact on the oocyte maturation. Consequently, inhibition of meiosis has been used to improve developmental competence of oocytes without reducing blastocyst rates. Moreover, the meiotic stage influences the ability of oocytes to survive cryopreservation. This work analyzes the effect of the inhibition of meiosis (prematuration) on the freezability of the bovine oocyte. Cumulus-oocyte complexes (COCs) were recovered from slaughterhouse ovaries. Inmature oocytes (I) with compact cumulus and evenly granulated cytoplasm were selected. Prematuration (PM) was performed by incubating COCs for 22h in TCM199 NaHCO3 and roscovitine 25μM. IVM was accomplished in TCM199 NaHCO3, 10% FCS, FSH-LH and 17β-estradiol. Oocytes were subjected to 5 treatments prior the vitrification (see table). COCs were partially denuded from cumulus cells and vitrified/warmed using the OPS system (Vajta et al. 1998 Mol. Reprod. Dev. 51, 53–58). Warmed oocytes were fertilized (Day 0) and presumptive zygotes having a normal morphological appearance were cultured in SOFaa+5% of FCS (Day 3); elements with degenerated appearance were discarded and recorded. Fresh oocytes submitted to IVM (c-M) or prematured and matured (c-PM+M) were fertilized and cultured as controls. Data were analyzed by ANOVA and Duncan’s multiple range test and expressed as LSM±SE. Developmental data are referred to the zygotes cultured. Only oocytes vitrified after IVM reached the blastocyst stage, but at lower rates than fresh controls. However, no differences were found between treatments at any developmental stage. Oocytes vitrified both as prematured+matured and immature oocytes showed increased proportions (P&amp;lt;0.01) of degenerated oocytes (37.3±5.9 and 49.9±5.9, respectively), as compared with oocytes matured before vitrification (17.6±5.9). These results show that effects induced by incubation with roscovitine (Lonergan et al. 2003 Mol. Reprod. Dev. 64, 369–378) in combination with cryodamage compromise the oocyte developmental ability. Supported by CICYT, AGL2001-379.

Oxygen and ventilator weaning during inpatient pediatric pulmonary rehabilitation.

Rates of oxygen and ventilator weaning, and factors related to successful weaning in inpatient pediatric pulmonary programs for infants and young children, have not been frequently reported in the literature. A retrospective review was conducted of 34 infants and toddlers with either a diagnostic condition of prematurity (PM) or congenital anomalies/neuromuscular disease (CA/NM) discharged from an inpatient pulmonary program. These cases represent 67 hospital admission-discharge episodes over a 6-year period. The rate of successful oxygen weaning (decrease to 0 hr per day) and ventilator weaning (decrease to <12 hr per day) and predictive factors related to successful ventilator weaning per admission-discharge episode were examined. Successful oxygen weaning was achieved during 24% and successful ventilator weaning was achieved during 30% of the admission-discharge episodes. No significant relationships were found between the selected demographic and clinical factors and oxygen weaning. Using a logistic regression model, the major variable associated with successful ventilator weaning per admission-discharge episode was diagnostic condition. Age at admission and the presence of comorbidities added slightly to the prediction model. The overall model yielded 86% accuracy for predicting a decrease in ventilator hours. However, projecting in which episodes children will not be weaned (negative predictive value = 88.9%) was more accurate than projecting in which episodes children will be weaned (positive predictive value = 73.3%). Although the program achieved a relatively low rate of successful ventilator weaning, children with a diagnostic condition of prematurity were more likely to be successfully weaned during inpatient pulmonary rehabilitation.

A Matter of life and Death for Manitoba’s Children

To determine the fertility and child mortality rates for Manitoba. Fertility and mortality rates were derived from the Population Health Research Data Repository and Vital Statistics, for 1994 through 1998. Data are presented by 12 Regional Health Authorities (RHAs), 12 Winnipeg Community Areas (CAs) and by income quintile. Each indicator is correlated with PMR (the age- and sex-adjusted premature mortality rate, i.e., death before age 75) and SEFI (Socioeconomic Factor Index, a standardized composite index), both considered proxies for overall health and socioeconomic well-being of populations. Manitoba's total fertility rate was 1.77 children per woman, ranging from 1.62 to 3.15 by RHA, and 1.21 to 2.30 by Winnipeg CA. Manitoba's infant mortality rate was 6.6/1000 (or 5.5/1000 excluding < 500 g or < 20 weeks gestation), ranging from 4.5 to 10.2 by RHA (4.2 to 9.8 exclusive), and 3.7 to 8.4 by Winnipeg CA (2.7 to 6.7). There was a gradient of infant mortality by income quintile (p < 0.001), with double the rate comparing lowest to highest. Child mortality rates varied geographically and by gender, with northern children at greatest risk. Injury was the leading cause of death (52% for ages 1 through 9, 75% for ages 15 to 19). Fertility rates, as well as infant and child mortality rates, were positively associated with PMR and SEFI, with substantial geographical variation.

Milk from Mothers of Both Premature and Full-Term Infants Provides Better Antioxidant Protection than Does Infant Formula

We hypothesized that premature (PT) infants' mother's milk may provide antioxidant advantages compared with milk from mothers of full-term (FT) infants, and human milk may provide antioxidant properties not seen in infant formulas. We designed three experiments to test these hypotheses. Experiment 1 assessed resistance to oxidative stress of human milk and formulas designed for FT and PT infants. Experiment 2 determined differences in resistance to oxidative stress between milk from mothers of FT and PT infants, including analysis of catalase activity. Experiment 3 examined factors in human milk that may account for increased resistance to oxidative stress. In experiment 1, we induced physiologic oxidative stress in human milk (n = 5) and formula (n = 2) and measured ascorbate radical using electron paramagnetic resonance. Results indicated the following: 1) during oxidative stress, ascorbate may be spared in human milk compared with formula; 2) ascorbate radical production is more intense in formula compared with human milk, with or without oxidative stress; and 3) oxygen consumption in human milk is less than that in formula, with or without oxidative stress. In experiment 2, milk samples were collected from mothers of PT (n = 28) and FT (n = 17) infants at wk 1, 2, and 12 of lactation. No differences in oxygen consumption after oxidative stress appeared between PT and FT milk. Catalase levels in human milk increased with time. In experiment 3, addition of catalase, superoxide dismutase, and glutathione peroxidase to formulas (n = 4) increased resistance to oxidative stress. Denaturing endogenous enzymes did not decrease the ability of human milk to resist oxidative stress. Ferrous sulfate plus vitamin C added to human milk and formulas fortified with iron increased oxidative stress. Addition of iron chelators to formula reduced oxidative stress. In conclusion, human milk has better antioxidant protection than do formulas, perhaps because of the higher iron content of formulas. Milk from mothers of PT and FT infants has equal resistance to oxidative stress.

Superoxide Dismutase and Glutathione Peroxidase Content of Human Milk From Mothers of Premature and Full‐Term Infants During the First 3 Months of Lactation

ABSTRACTBackgroundHuman milk contains various bioactive compounds including numerous immunologic factors, enzymes, growth factors, and hormones. However, the change during the course of lactation in many of these compounds has not been fully characterized. Therefore, the objective of the present study was to measure the activity of the enzymes superoxide dismutase (SOD; Enzyme Commission number [EC] 1.15.1.1) and glutathione peroxidase (SeGSHPx; EC 1.11.1.9) in human milk, to record changes in enzyme activity over time and to determine whether there are differences in activity between the milk of mothers of full‐term (FT) and premature (PT) infants.MethodsNine samples were collected from each of 15 mothers (32 ± 4 years of age; mean ± standard deviation) of FT infants (gestational age, 40 ± 1 weeks; birth weight, 3544 ± 417 g) and 19 mothers (28 ± 5 years of age) of healthy PT infants (gestational age, 29 ± 4 weeks; birth weight, 1312 ± 479 g). Samples were collected within a week of birth (±1 day) and thereafter for 8 weeks, with a final collection at 12 weeks.ResultsDuring the 12‐week study period, in both groups, total milliunits of GHSPx and SeGHSPx per milligram protein and SOD per per milligram protein increased, whereas protein content declined. SeGHSPx per milliliter milk was higher in the PT group at week 1 (92 ± 30 mU/mL vs. 73 ± 21 mU/mL), week 2 (93 ± 28 mU/mL vs. 75 ± 24 mU/mL), and week 7 (85 ± 24 mU/mL vs. 68 ± 22 mU/mL). The SOD activity per milliliter milk and milligram protein was higher throughout the entire study in the FT milk.ConclusionsBecause mothers of PT infants may produce less milk than those of FT infants, PT infants may be at a disadvantage for antioxidant protection from these enzymes.

Superoxide dismutase and glutathione peroxidase content of human milk from mothers of premature and full-term infants during the first 3 months of lactation.

Human milk contains various bioactive compounds including numerous immunologic factors, enzymes, growth factors, and hormones. However, the change during the course of lactation in many of these compounds has not been fully characterized. Therefore, the objective of the present study was to measure the activity of the enzymes superoxide dismutase (SOD; Enzyme Commission number [EC] 1.15.1.1) and glutathione peroxidase (SeGSHPx; EC 1.11.1.9) in human milk, to record changes in enzyme activity over time and to determine whether there are differences in activity between the milk of mothers of full-term (FT) and premature (PT) infants. Nine samples were collected from each of 15 mothers (32 +/- 4 years of age; mean +/- standard deviation) of FT infants (gestational age, 40 +/- 1 weeks; birth weight, 3544 +/- 417 g) and 19 mothers (28 +/- 5 years of age) of healthy PT infants (gestational age, 29 +/- 4 weeks; birth weight, 1312 +/- 479 g). Samples were collected within a week of birth (+/- 1 day) and thereafter for 8 weeks, with a final collection at 12 weeks. During the 12-week study period, in both groups, total milliunits of GHSPx and SeGHSPx per milligram protein and SOD per per milligram protein increased, whereas protein content declined. SeGHSPx per milliliter milk was higher in the PT group at week 1 (92 +/- 30 mU/mL vs. 73 +/- 21 mU/mL), week 2 (93 +/- 28 mU/mL vs. 75 +/- 24 mU/mL), and week 7 (85 +/- 24 mU/mL vs. 68 +/- 22 mU/mL). The SOD activity per milliliter milk and milligram protein was higher throughout the entire study in the FT milk. Because mothers of PT infants may produce less milk than those of FT infants, PT infants may be at a disadvantage for antioxidant protection from these enzymes.

Relationship between bone mineralization and aluminium in the healthy infant.

This prospective study was designed to assess the relationship between variations of serum Aluminium levels and bone mineralization, which is one of its target tissues, in healthy premature (PT) and fullterm (FT) infants. Lumbar spine bone mineral density (BMD) and content (BMC) studied by dual energy X-ray absorptiometry were compared to serum aluminium (S-Al), Ca (S-Ca), P (S-P), osteocalcin, alkaline phosphatase activity (S-AP), and 25 OH Vitamin D (25 OH D) by simple and multiple regressions in healthy PT (n = 44) following their hospital discharge and FT (n = 82). PT (gestational age at birth (mean +/- 1 s.d.) 32 +/- 2 weeks) and FT were 43 +/- 39 and 36 +/- 32 weeks old respectively. In PT multiple stepwise regression analysis including gestational age at birth, postconceptional age and postnatal age displayed only a significant correlation between BMD or BMC and postnatal age and a negative one with S-Al. In FT correlations were found between BMD or BMC and age and S-Ca. In PT, variations in blood Al are associated with developmental delays. Care should be taken to lessen Al levels, even in healthy PT babies.

Eating behavior and pregnancy outcome

The association between clinical eating disorders, maternal body weight, shape, and eating concerns, and the birth of low-birth-weight infants (LBW; less than 2500 g) was investigated using a retrospective case–control study. Eighty-eight women delivering LBW infants were interviewed and then divided into two groups—those delivering term, small-for-gestational-age infants (SGA; 37 or more completed weeks, n=34) and those delivering premature infants (less than 37 completed weeks, n=54). There were 86 reference women (CTRL) matched for age, parity, and health insurance status, who delivered babies with birth weights greater than 2500 g. In the week postpartum, women delivering term SGA, premature (PREM), and CTRL infants were interviewed using a semistructured interview. One section of this interview included a modified version of the Eating Disorder Examination (EDE), which retrospectively generated, over the previous 12 months, diagnosis of an eating disorder and maternal “normative” weight and shape concerns. In the 3 months before pregnancy, 32% of SGA women, 9% PREM women, and 5% of reference women were diagnosed as having a clinical eating disorder. Women with a past history of an eating disorder had no greater risk of delivering a low-birth-weight infant. Women delivering SGA infants reported elevated eating disorder psychopathology postdelivery (Eating Disorders Inventory, EDI) and more disturbances in eating behavior before and during pregnancy. Unique predictors for delivery of a LBW term SGA infant were: low maternal prepregnancy body weight, smoking, low maternal weekly weight gain, and elevated EDI (Bulimia subscale). Unique predictors for delivery of a LBW premature infant were: lower maternal occupational status, vomiting in pregnancy, and lower dietary restraint. Women with disordered eating were shown to be at greater risk of delivering term SGA infants. Predictors of term growth retardation are partly determined by maternal behavior.

84 THE ONSET OF WALKING INDEPENDENTLY: ARE THERE QUALITATIVE DIFFERENCES BETWEEN PRETERH AND FULLTERH INFANTS?

There are marked individual differences in the ages at which children acquire the ability to walk without support. It is also known that children who are late in acquiring this ability have a higher risk for developmental disorders. Less attention has been paid to the quality of movement expressed in the first attempts at walking alone. Qualitative assessments of early walking may provide a sensitive means for detecting those infants with developmental impairments. The aim of the study was to devise a standardised instrument for the qualitative assessment of early walking in the free field situation. To control for differences in walking experience, all subjects were assessed 14 days after being able to walk 5 metres independently. The study group consisted of 52 children of whom 33 were born prematurely (PT) (and further distinguished in terms of being small (SGA)- or appropriate (AGA)-for-gestational age) and 19 were fullterm infants (FT). Walking performance was judged to be optimal, near poor and poor based on a number of criteria. The optimal criteria were met by 12 PTAGA infants and 1 PTSGA. There were 2 FT, 1 PTAGA and 5 PTSGA in the near poor group. 8 PTAGA and 6 PTSGA but no FT children showed poor walking quality. Those who were SGA were overrepresented in the near poor and poor categories.

Maturation of peripheral nerves in preterm infants: Proprioceptive and motor nerve conductions of tibial nerve

Premature birth induces a profound change in the environmental factors affecting nerve maturation. The proprioceptive sensory and motor nerve conduction velocities (NCV) of the posterior tibial nerve, which reflect peripheral nerve maturation, have been measured in 3 groups of newborns. Two groups of premature (PT) babies, studied when they reached the expected date of birth (group I, gestational age (GA) at birth, 28-31 weeks, n = 8; group II, GA at birth, 32-35 weeks, n = 6) were compared to 9 normal full-term (FT) newborns. As previously shown, the motor NCV of PT babies at a post-conceptional age close to term is similar to that of FT newborns: group I, 22.70 +/- 2.95 m/s (mean +/- SD); group II, 25.90 +/- 4.61 m/s; FT, 25.48 +/- 4.09 m/s. The proprioceptive sensory NCV was significantly lower in group I (21.59 +/- 4.39 m/s) than in group II (31.89 +/- 4.15 m/s) and FT newborns (32.22 +/- 6.56 m/s) (p less than 0.01). Such a delay in maturation could be responsible for the subtle clinical dysfunctions often observed in PT babies.

SERUM THYROGLOBULIN CONCENTRATIONS IN INFANTS OF VARIOUS MATURITY

A few studies have suggested that s-thyroglobulin (Tg) in cord blood is higher in premature (PT) than in fullterm (FT) babies. S-Tg was determined by RIA in 33 routinely sampled blood from 33 infants. S-Tg ranged from 2.5-148 ug/l, median 33 ug/l, signficantly higher than in adults (p < 0.001). Subsequently, detailed informations on s-Tg, T4, T3, TSH, and thyroid hormone-binding proteins TBG, TBPA, and albumin were conducted in 14 FT, in 6 small-for-date (SGA) infants born at term (chron.age l-303 days, weight 2400-9000 g) and in 12 PT babies (gest.age 33-36 weeks, chron.age 50-970 days, weight 2930-11800 g).Results: 1) Wide range values of s-Tg were seen, 21-108 ug/l, median 42 ug/l, in FT, SGA and PT-infants, with no significant differences between the groups, but higher levels than in adults. 2) S-Tg did not change significantly with chronologocal age or body-weight (R -0.41, p> 0.1) in the material as a whole, but in FT-infants s-Tg was correlated to s-T4 (R 0.48, p=0.05). Individual data showed a decrease of s-Tg with age and increase with s-T3. 3) No correlation was found between s-Tg and s-TSH or thyroid hormone-binding proteins (p> 0.1).Conclusion: S-Tg is increased in FT, SGA and PT-infants compared to adults, but do not correlate to maturity. These findings have to be considered at the neonatal thyroid screening programmes.

Vitamin A and E content of human milk at early stages of lactation

The influence of gestational age and lactational stage on carotene, retinol ester, α-tocopherol and γ-tocopherol content of early human milk was studied. These nutrients were analyzed simultaneously using normal phase high-performance liquid chromatography. Serial samples of colostrum and early milk representative of complete early morning expressions were obtained during the first 6 weeks postpartum from mothers giving birth prematurely (PT) and at term (FT). Colostrum carotene content declined significantly during the first week of lactation. There was no apparent gestational age effect on milk carotene levels. The longitudinal pattern of change observed for milk retinol ester and a-tocopherol content was however, significantly different between PT and FT milk. Retinol ester levels were similar on days 1–2 postpartum reaching a maximal level on days 3–4 postpartum in FT milk. For PT milk the maximum retinol ester concentration occurred on days 6–7 postpartum. Retinol ester content decreased throughout lactation. The rate of decline was more marked for FT milk. The concentration of α-tocopherol in colostrum was higher in FT milk. On all subsequent days examined the level of a-tocopherol was greater in PT milk. For both FT and PT milk the α-tocopherol concentration was higher during the first week of lactation when compared with following weeks. γ-Tocopherol levels were not influenced by gestational age or lactational stage. Levels of milk vitamin A and E did not appear to correlate with maternal intake. Colostrum levels of vitamin A and E may imply active sequestration by the mammary gland in compensation for limited placental transport. Early milk content of vitamin A and E appears to parallel mammary gland lipid synthesis.

Trans fatty acids in human milk lipids: influence of maternal diet and weight loss

Geometric and positional isomers of octadecanoic acid in milk expressed during the first 9 weeks of lactation were determined for mothers delivering prematurely (PT) and at term (FT). Total C18:1 concentration was lower in PT than FT milk. C18:1 trans (elaidic acid) content was higher in PT and FT colostrum compared with subsequent milk samples. No relationship was observed between C18:1 trans level in milk and oleic acid, linoleic acid, total fatty acid levels, or volume of milk expressed. While gestational age and lactational stage appeared to affect the trans fatty acid pattern, the overriding influence was rate of maternal postpartum weight loss. Effect of weight loss on milk trans fatty acid levels was independent of maternal diet. Trans fatty acid content of milk as a function of recent maternal fat intake was also demonstrated. This study indicates that infants receiving human milk ingest levels of trans fatty acids reflecting short and long term maternal diet.

1205 LACTATE TURNOVER IS INCREASED IN THE NEONATE RELATIVE THE ADULT

Gluconeogenesis is a major component of glucose production. The contribution of specific gluconeogenic precursors has not been studied in the newborn relative to the adult. Glucose production and lactate production have been evaluated by prime constant infusion of 45 ug·kg−1 min−1 D-[6, 6- 2D]glucose and 20 ug·kg−1 min−1 [3- 13C]lactate in 3 AGA premature(PT) [BW 2088±174 gm (M±SEM) & GA 34.3±0.9 wks] & 4 AGA term infants(T) [BW 3316±175 gms & GA 41±0.4 wks] at 31±7 hrs after birth & compared to studies in 4 adults(A). Ra(production) was measured during infusion of 0.9% NaCL at 0.06 ml · kg−1 min−1 and analyzed by Gas Chromatograph Mass Spectometry(GCMS). Turnover period results are shown: Ra(Glucose) & Ra(Lactate) were ↑ in both PT & T relative to A, but not between PT & T. There was an ↑ ratio of Ra(Lactate) to Ra (Glucose) in both PT & T relative to A but not between PT & T. This is consistent with the relationship of Ra(Glucose) measured by the non-recycling tracer D-[6,6- 2D]glucose in these studies compared to Ra(Glucose) measured with the recycling tracer D-[U- 13C]glucose in prior studies. Availability of lactate due to recycling may be a mechanism for sparing of gluconeogenic amino acid precursors in the anabolic newborn.