Some new studies, beginning with this open access study from New Zealand:
TItle: Feasibility of Standardized Human Milk Collection in Neonatal Care Units.
In: Scientific Reports 2019 Oct 4;9(1):14343. doi: 10.1038/s41598-019-50560-y.
Authors: Galante L, Vickers MH, Milan AM, Reynolds CM, Alexander T, Bloomfield FH, Pundir S.
Abstract: "Research in human lactation is a growing field. However, difficulties in studying human milk originate from the dynamicity of its composition. Using standardized collection protocols is mandatory to minimize variation and warrant comparability of findings across different studies. Yet, information on the feasibility of collecting human milk with standardized procedures, especially in neonatal units, are lacking. The present study aims to report on the feasibility and difficulties to collect human milk according to a standardized protocol, during early lactation from women who gave birth to preterm infants. Human milk was collected from 129 mothers of moderate- to late-preterm infants according to two variations of a standard protocol which differed for number of collection time-points. Collection rates and adherence to the sampling protocol were evaluated together with reason for missed collection. Collection of ≥1 sample was successful for 80% of the mothers. However adherence to the standard protocol was overall low (36% and 27%). Collection rates were different between the two protocol variations (73% against 92%, p ≤ 0.001). Amongst the reason for missed collection, low milk supply was the most recurrent (40%). Our findings show that while collecting human milk in neonatal units is achievable, obtaining standard and comparable samples results challenging." Full text: https://www.nature.com/articles/s41598-019-50560-y
Title: The chemical synthesis of human milk oligosaccharides: Lacto-N-tetraose (Galβ1→3GlcNAcβ1→3Galβ1→4Glc).
In: Carbohydrate Research 2019 Sep 25;486:107824. doi: 10.1016/j.carres.2019.107824. [Epub ahead of print]
Authors: Bandara MD, Stine KJ, Demchenko AV.
Highlights: "The total synthesis of lacto-N-tetraose has been completed using both linear and convergent synthesis approaches. The linear approach was proven to be more efficient in this application. New synthetic protocols for different glycosidic linkages have been developed and refined. New methods for obtaining individual HMO help to improve understanding their roles and boost practical applications."
Title: Large scale production of lacto-N-biose I, a building block of type I human milk oligosaccharides, using sugar phosphorylases.
In: Bioscience, Biotechnology, and Biochemistry 2019 Sep 28:1-8. doi: 10.1080/09168451.2019.1670047. [Epub ahead of print]
Author: Nishimoto M.
Abstract: "Human milk oligosaccharides (HMOs) have drawn attention for their contribution to the explosive bifidobacterial growth in the intestines of neonates. We found that bifidobacteria can efficiently metabolize lacto-N-biose I (LNB), the major building blocks of HMOs, and we have developed a method to synthesize LNB by applying this system. We produced LNB on a kilogram scale by the method. This proved that, among the enterobacteria, only bifidobacteria can assimilate LNB, and provided the data that supported the explosive growth of bifidobacteria in neonates. Furthermore, we were also able to reveal the structure of LNB crystal and the low stability for heating at neutral pH, which has not been clarified so far. In this paper, using bifidobacteria and LNB as examples, I describe the research on oligosaccharide synthesis that was conducted by utilizing a sugar metabolism. Abbreviations: LNB: lacto-N-biose I; GNB: galacto-N-biose; HMOs: human milk oligosaccharides; GLNBP: GNB/LNB phosphorylase; NahK: N-acetylhexosamine 1-kinase; GalT: UDP-glucose-hexose-1-phosphate uridylyltransferase; GalE: UDP-glucose 4-epimerase; SP: sucrose phosphorylase."
Title: No Association between Glucocorticoid Diurnal Rhythm in Breastmilk and Infant Body Composition at 3 Months.
In: Nutrients 2019 Oct 2;11(10). pii: E2351. doi: 10.3390/nu11102351.
Authors: Hollanders J, Dijkstra LR, van der Voorn B, Kouwenhoven SMP, Toorop AA, van Goudoever JB, Rotteveel J, Finken MJJ.
Abstract: "Objective: Glucocorticoids (GCs) in breastmilk have previously been associated with infant body growth and body composition. However, the diurnal rhythm of breastmilk GCs was not taken into account, and we therefore aimed to assess the associations between breastmilk GC rhythmicity at 1 month and growth and body composition at 3 months in infants. Methods: At 1 month postpartum, breastmilk GCs were collected over a 24-h period and analyzed by LC-MS/MS. Body composition was measured using air-displacement plethysmography at 3 months. Length and weight were collected at 1, 2, and 3 months. Results: In total, 42 healthy mother-infant pairs were included. No associations were found between breastmilk GC rhythmicity (area-under-the-curve increase and ground, maximum, and delta) and infant growth trajectories or body composition (fat and fat free mass index, fat%) at 3 months. Conclusions: This study did not find an association between breastmilk GC rhythmicity at 1 month and infant's growth or body composition at 3 months. Therefore, this study suggests that previous observations linking breastmilk cortisol to changes in infant weight might be flawed by the lack of serial cortisol measurements and detailed information on body composition."
Open access: https://www.mdpi.com/2072-6643/11/10/2351