Dose-response Relationship Between Donor Human Milk, Mother's Own Milk, Preterm Formula, and Neonatal Growth Outcomes.

BACKGROUND: A dose-response relationship between proportions of donor human milk (DHM) intake and in-neonatal intensive care unit (in-NICU) growth rates, if any, remains poorly defined. Objective was to evaluate interrelationships between percentages of DHM, mother's own milk (MOM), and preterm formula (PF) intake and neonatal growth parameters at 36 weeks postmenstrual age or NICU discharge. METHODS: Infants eligible for this single-center retrospective study were inborn at ≤32 weeks gestation or ≤1800 g, stayed in the NICU for ≥7 days, and received enteral nutrition consisting of human milk fortified with Enfamil human milk fortifier acidified liquid. Study exposures were defined as 10% increments in the total volumetric proportions of infant diet provided as MOM, DHM, or PF. Outcomes were growth parameters at 36 weeks postmenstrual age or NICU discharge. Multivariable linear regression modeled the adjusted additive effect of infant diet on individual growth parameters. RESULTS: A total of 314 infants records were eligible for analysis. Using MOM as reference, the adjusted mean growth velocity for weight significantly decreased by 0.17 g ·â€Škg ·â€Šday for every 10% increase in DHM intake, but did not vary with PF intake. The adjusted mean change in weight z score significantly decreased with increasing proportion of DHM intake but significantly improved with increasing PF intake. The adjusted mean head circumference velocity was significantly decreased by 0.01 cm/wk for every 10% increase in DHM intake, in reference to MOM, but did not vary with PF intake. Neither proportion of DHM nor PF intake was associated with length velocity. CONCLUSIONS: When DHM and MOM are fortified interchangeably, preterm infants receiving incremental amounts of DHM are at increased risk of postnatal growth restriction. The dose-response relationship between DHM, MOM, and PF and long-term growth and neurodevelopmental outcomes warrants further research.

Detection of lymphoproliferative disease virus in Iowa Wild Turkeys (Meleagris gallopavo): Comparison of two sections of the proviral genome.

An accurate diagnostic test is an essential aspect of successfully monitoring and managing wildlife diseases. Lymphoproliferative Disease Virus (LPDV) is an avian retrovirus that was first identified in domestic turkeys in Europe and was first reported in a Wild Turkey (Meleagris gallopavo) in the United States in 2009. It has since been found to be widely distributed throughout North America. The majority of studies have utilized bone marrow and PCR primers targeting a 413-nucleotide sequence of the gag gene of the provirus to detect infection. While prior studies have evaluated the viability of other tissues for LPDV detection (whole blood, spleen, liver, cloacal swabs) none to date have studied differences in detection rates when utilizing different genomic regions of the provirus. This study examined the effectiveness of another section of the provirus, a 335-nucleotide sequence starting in the U3 region of the LTR (Long Terminal Repeat) and extending into the Matrix of the gag region (henceforth LTR), for detecting LPDV. Bone marrow samples from hunter-harvested Wild Turkeys (n = 925) were tested for LPDV with the gag gene and a subset (n = 417) including both those testing positive and those where LPDV was not detected was re-tested with LTR. The positive percent agreement (PPA) was 97.1% (68 of 70 gag positive samples tested positive with LTR) while the negative percent agreement (NPA) was only 68.0% (236 of 347 gag negative samples tested negative with LTR). Cohen's Kappa (κ = 0.402, Z = 10.26, p<0.0001) and the McNemar test (OR = 55.5, p<0.0001) indicated weak agreement between the two gene regions. We found that in Iowa Wild Turkeys use of the LTR region identified LPDV in many samples in which we failed to detect LPDV using the gag region and that LTR may be more appropriate for LPDV surveillance and monitoring. However, neither region of the provirus resulted in perfect detection and additional work is necessary to determine if LTR is more reliable in other geographic regions where LPDV occurs.

Macronutrient analysis of donor human milk labelled as 24 kcal/oz.

OBJECTIVE: To measure the macronutrient content (MNC) of donor human milk labelled as 24 kcal/oz ("high-calorie DHM," hcDHM), compare to bank-labelled MNC, and examine variability of hcDHM MNC among milk banks. STUDY DESIGN: MNC was measured with near-infrared spectroscopy for 75 convenience samples from five milk banks collected during September 2016-July 2017. Concordance of measured MNC with labelled values was evaluated using three different thresholds: within ±20%, similar to FDA labelling standards for class II nutrients in foods; ±10%; and ±5%. RESULTS: Protein and caloric content differed significantly between measured and labelled values and varied significantly among milk banks. Measured caloric content ranged from 16.50 to 30.27 kcal/oz, with 89.3% of hcDHM samples within ±20%, 58.7% within ±10%, and 18.7% within ±5% of labelled content. CONCLUSIONS: MNC of hcDHM used in clinical practice shows variation that may result in differences from desired diet. The clinical implications of such differences are unexplored.

Systematic Review of the Human Milk Microbiota.

Human milk-associated microbes are among the first to colonize the infant gut and may help to shape both short- and long-term infant health outcomes. We performed a systematic review to characterize the microbiota of human milk. Relevant primary studies were identified through a comprehensive search of PubMed (January 1, 1964, to June 31, 2015). Included studies were conducted among healthy mothers, were written in English, identified bacteria in human milk, used culture-independent methods, and reported primary results at the genus level. Twelve studies satisfied inclusion criteria. All varied in geographic location and human milk collection/storage/analytic methods. Streptococcus was identified in human milk samples in 11 studies (91.6%) and Staphylococcus in 10 (83.3%); both were predominant genera in 6 (50%). Eight of the 12 studies used conventional ribosomal RNA (rRNA) polymerase chain reaction (PCR), of which 7 (87.5%) identified Streptococcus and 6 (80%) identified Staphylococcus as present. Of these 8 studies, 2 (25%) identified Streptococcus and Staphylococcus as predominant genera. Four of the 12 studies used next-generation sequencing (NGS), all of which identified Streptococcus and Staphylococcus as present and predominant genera. Relative to conventional rRNA PCR, NGS is a more sensitive method to identify/quantify bacterial genera in human milk, suggesting the predominance of Streptococcus and Staphylococcus may be underestimated in studies using older methods. These genera, Streptococcus and Staphylococcus, may be universally predominant in human milk, regardless of differences in geographic location or analytic methods. Primary studies designed to evaluate the effect of these 2 genera on short- and long-term infant outcomes are warranted.

Five-Year Secular Trends and Predictors of Nonconsent to Receive Donor Milk in the Neonatal Intensive Care Unit.

OBJECTIVE: To identify independent maternal and infant factors associated with donor milk nonconsent and to examine secular trends in nonconsent rates. MATERIALS AND METHODS: Mothers of infants eligible to receive donor milk (≤32 weeks of gestation or ≤1,800 g) born between August 2010 and 2015 were included. Multivariable logistic regression modeled odds of nonconsent. RESULTS: Of the 486 mother/infant dyads from the first 5 years of the donor milk program, nonwhite race (adjusted odds ratio [aOR] 1.69; 95% confidence interval [CI] 1.04-2.76) and increasing gestational age (aOR 1.11; 95% CI 1.03-1.21) independently predicted nonconsent. Each year the program existed, there was a 48% reduction in odds of nonconsent (aOR 0.52; 95% CI 0.43-0.62). The most common reason given for nonconsent was "it's someone else's milk." CONCLUSION: Program duration was associated with reduced nonconsent rates and may reflect increased exposure to information and acceptance of donor milk use among neonatal intensive care unit staff and parents. Despite overall improvements in consent rates, race-specific disparities in rates of nonconsent for donor milk persisted after 5 years of this donor milk program. Further research is warranted to clarify the basis for race-based disparities in donor milk nonconsent rates, with the goal of designing interventions to reduce donor milk refusal among minority mothers.

Adolescent nicotine alters dendritic morphology in the bed nucleus of the stria terminalis.

Adolescent nicotine increases dendritic elaboration in several areas associated with the extended amygdala. It also increases anxiety-like behavior in adulthood. An unresolved question is whether adolescent nicotine alters dendritic structure in the bed nucleus of the stria terminalis (BNST), which may contribute to altered anxiety-like behavior. To investigate this possibility, adolescent male Sprague-Dawley rats were administered nicotine (0.5mg/kg/day) 3 days a week for 2 consecutive weeks, starting at postnatal day P (32). 17 days following the end of dosing, brains were processed for Golgi-Cox staining, and neurons were digitally reconstructed in three dimensions. Animals previously treated with nicotine exhibited an increase in the total number of branches and total length of dendrites on BNST neurons. Sholl analysis revealed an increase in the number of intersections with concentric spheres, increased amount of dendritic material within concentric spheres, and an increase of dendritic branching within concentric spheres occurring between 20 and 300 µm from the soma in dendrites. Collectively, our results show that adolescent nicotine alters dendritic structure (by triggering new branch growth), and, by inference, connectivity of the BNST, which may contribute to alterations in behavior induced by adolescent nicotine.