Fatty Acid Composition of the Erythrocyte Membranes Varies between Early-Term, Full-Term, and Late-Term Infants in Japan.

BACKGROUND: Term infants can be categorized into 3 sub-groups: early term (37w0d to 38w6d), full term (39w0d to 40w6d), and late term (41w0d and beyond). However, the fatty acid composition among the 3 groups of term infants has not been investigated. The association between fatty acid composition and gestational period of term infants in Japan is unclear. METHODS: We assessed the fatty acid composition of maternal erythrocyte membranes in the third trimester and of cord erythrocyte membranes at birth in 212 healthy term Japanese infants using data from a prospective hospital-based cohort study. RESULTS: In maternal erythrocyte membranes, docosahexaenoic acid (DHA) levels and omega-3 index were significantly higher in the late-term group than in the early-term group. In cord erythrocyte membranes, DHA levels were not significantly different between the 3 groups; late-term infants showed significantly higher DHA/arachidonic acid (ARA) and lower 20: 3n-6 and ARA levels compared to early-term infants. Gestational period positively correlated with the DHA status in maternal and cord erythrocyte membranes. CONCLUSIONS: Fatty acid composition in maternal and cord erythrocyte membranes varies between early-, full-, and late-term infants, and the greater gestational period may contribute to the relatively high n-3 polyunsaturated fatty acids status in term infants. Furthermore, maternal DHA status in the third semester directly correlates with gestational period in pregnant Japanese women.

Relationship between Changes in Fatty Acid Composition of the Erythrocyte Membranes and Fatty Acid Intake during Pregnancy in Pregnant Japanese Women.

OBJECTIVE: Docosahexaenoic acid (DHA) is an important nutrient required by pregnant women and fetuses. Several studies suggest that fatty acid composition changes during pregnancy. However, the association of longitudinal changes in erythrocyte fatty acid composition and dietary fatty acid intake during pregnancy is not well understood. We assessed the relationship between fatty acid composition of the erythrocyte membranes and fatty acid intake at each trimester in pregnant Japanese women. METHODS: We conducted a prospective hospital-based cohort study. We investigated fatty acid composition of the erythrocyte membranes and intake of fatty acids during the three trimesters in 178 healthy, pregnant Japanese women. RESULTS: The eicosapentaenoic acid and arachidonic acid percentage of the erythrocyte membranes significantly decreased. The percentages of linoleic acid and α-linolenic acid significantly increased during pregnancy. The DHA percentage in the erythrocyte membranes decreased from the second to the third trimester. The DHA percentage in the erythrocyte membranes positively correlated with DHA intake in the third trimester. CONCLUSION: In pregnant Japanese women, the fatty acid composition of the erythrocyte membranes markedly changed throughout pregnancy. The DHA intake in the third trimester may be insufficient to maintain DHA percentage in the maternal erythrocyte membranes.

Relationships between Psychophysiological Responses to Cycling Exercise and Post-Exercise Self-Efficacy.

Although self-efficacy (SE) is an important determinant of regular exercise, it is unclear how subjective and physiological states before, during, and after the exercise session affects post-exercise SE. The aim of this study was to clarify subjective and physiological factors affecting post-exercise SE assessed after a single exercise session at a physiologically equivalent level. Forty-three healthy volunteers (28 women, 15 men) completed an 82-min experimental session, comprising a 22-min pre-exercise rest, a 30-min steady-state cycling exercise at moderate intensity [40% of heart rate (HR) reserve], and a 30-min post-exercise rest. We measured physiological (HR) and subjective [Rating of Perceived Exertion (RPE), Feeling Scale (FS)] states during the experimental session. Autonomic states were assessed by power spectral analysis of heart rate variability (HRV) during pre- and post-exercise rest. Post-exercise SE, which was the participants' confidence in their ability to perform the 30-min exercise that they had just performed, was assessed at 30-min post-exercise. A stepwise multiple regression analysis, with post-exercise SE as the dependent variable and physiological and subjective measures of the exercise as candidate explanatory variables, showed that post-exercise SE was negatively correlated with RPE and positively correlated with FS at the end of the 30-min exercise. In addition, post-exercise SE was negatively correlated with high-frequency power of the post-exercise HRV, an index of parasympathetic function. These results indicate that post-exercise SE is related not only to subjective responses to the exercise but also to autonomic response after the exercise.

Risk factors for nosocomial infection in the neonatal intensive care unit by the Japanese Nosocomial Infection Surveillance (JANIS).

We evaluated the infection risks in the neonatal intensive care unit (NICU) using data of NICU infection surveillance data. The subjects were 871 NICU babies, consisting of 465 boys and 406 girls, who were cared for between June 2002 and January 2003 in 7 medical institutions that employed NICU infection surveillance. Infections were defined according to the National Nosocomial Infection Surveillance (NNIS) System. Of the 58 babies with nosocomial infections, 15 had methicillin-resistant Staphylococcus aureus (MRSA) infection. Multiple logistic regression analysis demonstrated that the odds ratio for nosocomial infections was significantly related to gender, birth weight and the insertion of a central venous catheter (CVC). When the birth weight group of more than 1, 500 g was regarded as the reference, the odds ratio was 2.35 in the birth weight group of 1,000-1,499 g and 8.82 in the birth weight group of less than 1,000g. The odds ratio of the CVC (+) for nosocomial infection was 2.27. However, other devices including artificial ventilation, umbilical artery catheter, umbilical venous catheter, and urinary catheter were not significant risk factors. The incidence of MRSA infection rapidly increased from 0.3% in the birth weight group of more than 1,500 g to 2.1% in the birth weight group of 1,000-1,499 g, and to 11.1% in the birth weight group of less than 1,000g. When the birth weight group of more than 1,500 g was regarded as the reference, multiple logistic regression analysis demonstrated that the odds ratio was 7.25 in the birth weight group of 1,000-1,499 g and 42.88 in the birth weight group of less than 1,000g. These odds ratios were significantly higher than that in the reference group. However, the application of devices did not cause any significant differences in the odds ratio for MRSA infection.

Serum free T4 and thyroid stimulating hormone levels in preterm infants and relationship between these levels and respiratory distress syndrome.

BACKGROUND: There have been few studies of the thyroid stimulating hormone (TSH) surge in extremely low-birthweight (ELBW) infants, and the relationship between thyroid hormones and respiratory distress syndrome (RDS) has yet to be clarified. The present study sought to determine the serum levels of free T4 (fT4) and TSH in ELBW infants and to examine the relationship between these levels and the development of RDS. METHODS: The authors measured serum fT4 and TSH levels soon after birth in 449 preterm infants, who were born at 22-36 weeks of gestation, and determined the associations between these levels, the incidence of RDS, and the recognized clinical factors associated with RDS. RESULTS: Serum fT4 and TSH levels, and the fT4/TSH ratio, in the group at 22-24 weeks of gestation were significantly lower than those in the group at 28-36 weeks. The levels and ratio increased significantly with increasing gestational age. There were significant correlations between the serum fT4 level and the birthweight, Apgar score, and gender, and between the serum TSH level and the gestational age, mode of delivery, and birthweight. No significant relationship between the incidence of RDS and the serum levels of fT4 and TSH was observed. CONCLUSION: The authors' results suggest that the serum levels of fT4 and TSH in ELBW infants are very low, and that these levels are not correlated with the occurrence of RDS.

Effects of extremely early enteral feeding on plasma glicentin levels in very-low-birthweight infants.

AIM: Glicentin, an active component of enteroglucagon, is considered to have a significant trophic action on the intestinal mucosa. We examined the effects of extremely early enteral feedings on the postnatal and postprandial changes in plasma glicentin levels in very-low-birthweight (VLBW) infants. METHODS: We measured the plasma glicentin concentrations before and after feedings at 1 or 2 days, 5 or 6 days and 14 days after birth in 21 VLBW infants. The subjects were randomly divided into an extremely early feeding group, which was started on breast milk within 24 h after birth, and a control group, which was started on breast milk more than 24 h after birth. RESULTS: Plasma basal concentrations of glicentin at 5 or 6 days and at 14 days after birth were significantly higher than those at 1 or 2 days after birth in the early feeding group. The basal glicentin level at 14 days after birth was significantly higher than that at 1 or 2 days. The basal levels at 5 or 6 days and at 14 days after birth in the early feeding group were significantly higher than those in the control group. Plasma glicentin concentrations after feeding were significantly higher than those before feeding at 5 or 6 days and 14 days after birth in the early feeding group, but those levels were significantly higher only at 14 days after birth in the control group. CONCLUSION: Our results suggest that extremely early enteral feedings may play an important role in the development of glicentin secretion and intestinal mucosal growth in the early period of life in VLBW infants.

Comparison of the phospholipid classes in human milk in Japanese mothers of term and preterm infants.

BACKGROUND: Phospholipids (PLs) play an essential role in the growth and brain development of infants. AIM: To investigate PL composition in human milk (HM), including lysophosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylcholine (PC) and sphingomyelin (SM), from healthy Japanese mothers. Analyses were performed on colostrum, transitional milk and mature milk from mothers of preterm and term infants. METHODS: HM samples were collected from mothers of 15 term infants (term group) and of 19 preterm infants (preterm group). PL composition was determined by two-dimensional thin-layer chromatography in conjunction with phosphorus analysis. RESULTS: In both groups, the PL content (% of total lipid) of mature milk was significantly lower than in colostrum. SM and PC were the main PLs in HM, but in the preterm group, the percentage of SM in mature milk was significantly higher and PC in mature milk was significantly lower than in the term group. CONCLUSION: The transition from colostrum to mature milk leads to an increase in SM and a decrease in PC in the HM of preterm infants, along with a decrease in PL content. This is the first report to demonstrate the differences in PL composition in HM between mothers of preterm and term infants.

Effects of parenteral lipid infusion on DNA damage in very low birth weight infants.

Very low birth weight (VLBW) infants are known to have poorly developed antioxidant system and may be at increased risk for radical damage. Previous studies have reported higher levels of lipid peroxide products in lipid emulsion used for parenteral nutrition. To examine the direct effects of parenteral lipid infusion on DNA damage in VLBW infants, we measured urinary 8-hydroxydeoxyguanosine (8-OHdG) levels in VLBW infants before, during, and after the parenteral lipid infusion. In both the lipid-infused and lipid-free groups, urinary 8-OHdG excretion levels at 14 days old were significantly (p < 0.01) lower than those at 2 and 7 days old. However, there were no significant differences in urinary 8-OHdG excretion levels between the lipid-infused and lipid-free groups at 2, 7, and 14 days old. Our results suggest that parenteral lipid infusion does not cause oxidative DNA damage, but irrespective of the infusion DNA damage during the first week of life is enhanced when compared with 14 days after birth in VLBW infants.