Roger Dyer

Mr. Roger Dyer


Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 December 2017 in Journal of Psychiatric Research
Verified
Journal Article
Closed access
SGSanjoy Ghosh
Sanjoy Ghosh
RDRoger Dyer
Roger Dyer
CBClare L. Beasley
Clare L. Beasley

15 October 2018 in Scientific Reports
Verified
Journal Article
Open access
PDF file
SMSara Moukarzel
Sara Moukarzel
RDRoger Dyer
Roger Dyer
Cyrielle GarciaCyrielle Garcia
Cyrielle Garcia
AWAlejandra Wiedeman
Alejandra Wiedeman
GBGuilaine Boyce
Guilaine Boyce
SISheila M. Innis
Sheila M. Innis
Human milk contains nutritional, immunoprotective and developmental components that support optimal infant growth and development. The milk fat globule membrane (MFGM) is one unique component, comprised of a tri-layer of polar lipids, glycolipids, and proteins, that may be important for brain development. MFGM is not present in most infant formulas. We tested the effects of bovine MFGM supplementation on reflex development and on brain lipid and metabolite composition in rats using the “pup in a cup” model. From postnatal d5 to d18, rats received either formula supplemented with MFGM or a standard formula without MFGM; a group of mother-reared animals was used as reference/control condition. Body and brain weights did not differ between groups. MFGM supplementation reduced the gap in maturation age between mother-reared and standard formula-fed groups for the ear and eyelid twitch, negative geotaxis and cliff avoidance reflexes. Statistically significant differences in brain phospholipid and metabolite composition were found at d13 and/or d18 between mother-reared and standard formula-fed groups, including a higher phosphatidylcholine:phosphatidylethanolamine ratio, and higher phosphatidylserine, glycerol-3 phosphate, and glutamine in mother-reared compared to formula-fed pups. Adding MFGM to formula narrowed these differences. Our study demonstrates that addition of bovine MFGM to formula promotes reflex development and alters brain phospholipid and metabolite composition. Changes in brain lipid metabolism and their potential functional implications for neurodevelopment need to be further investigated in future studies.

20 March 2018 in Nutrients
Verified
Journal Article
Open access
PDF file
AWAlejandra Wiedeman
Alejandra Wiedeman
KWKyly Whitfield
Kyly Whitfield
KMKaitlin M. March
Kaitlin M. March
NCNancy N. Chen
Nancy N. Chen
HKHou Kroeun
Hou Kroeun
SBSusan Barr
Susan Barr
Choline has critical roles during periods of rapid growth and development, such as infancy. In human milk, choline is mostly present in water-soluble forms (free choline, phosphocholine, and glycerophosphocholine). It is thought that milk choline concentration is influenced by maternal choline intake, and the richest food sources for choline are of animal origin. Scarce information exists on milk choline from countries differing in animal-source food availability. In this secondary analysis of samples from previous trials, the concentrations of the water-soluble forms of choline were quantified by liquid chromatography-tandem mass spectrometry in mature milk samples collected from lactating women in Canada (n = 301) and in Cambodia (n = 67). None of the water-soluble forms of choline concentrations in milk differed between Canada and Cambodia. For all milk samples (n = 368), free choline, phosphocholine, glycerophosphocholine, and the sum of water-soluble forms of choline concentrations in milk were (mean (95%CI)) 151 (141, 160, 540 (519, 562), 411 (396, 427), and 1102 (1072, 1133) µmol/L, respectively. Theoretically, only 19% of infants would meet the current Adequate Intake (AI) for choline. Our findings suggest that the concentrations in milk of water-soluble forms of choline are similar in Canada and Cambodia, and that the concentration used to set the infant AI might be inaccurate.

6 September 2017 in Nutrients
Verified
Journal Article
Open access
PDF file
ADAngela Devlin
Angela Devlin
CCCecil M. Y. Chau
Cecil M. Y. Chau
RDRoger Dyer
Roger Dyer
JMJulie Matheson
Julie Matheson
DMDeanna McCarthy
Deanna McCarthy
RGRuth E. Grunau
Ruth E. Grunau
Little is known about arachidonic acid (ARA) and docosahexaenoic acid (DHA) requirements in toddlers. A longitudinal, double blind, controlled trial in toddlers (n = 133) age 13.4 ± 0.9 months (mean ± standard deviation), randomized to receive a DHA (200 mg/day) and ARA (200 mg/day) supplement (supplement) or a corn oil supplement (control) until age 24 months determined effects on neurodevelopment. We found no effect of the supplement on the Bayley Scales of Infant and Toddler Development 3rd Edition (Bayley-III) cognitive and language composites and Beery–Buktenica Developmental Test of Visual–Motor Integration (Beery VMI) at age 24 months. Supplemented toddlers had higher RBC phosphatidylcholine (PC), phosphatidylethanolamine (PE), and plasma DHA and ARA compared to placebo toddlers at age 24 months. A positive relationship between RBC PE ARA and Bayley III Cognitive composite (4.55 (0.21–9.00), B (95% CI), p = 0.045) in supplemented boys, but not in control boys, was observed in models adjusted for baseline fatty acid, maternal non-verbal intelligence, and BMI z-score at age 24 months. A similar positive relationship between RBC PE ARA and Bayley III Language composite was observed for supplemented boys (11.52 (5.10–17.94), p < 0.001) and girls (11.19 (4.69–17.68), p = 0.001). These findings suggest that increasing the ARA status in toddlers is associated with better neurodevelopment at age 24 months.

7 April 2017 in Nutrients
Verified
Journal Article
Open access
PDF file
SMSara Moukarzel
Sara Moukarzel
LSLynda Soberanes
Lynda Soberanes
RDRoger Dyer
Roger Dyer
SASusan Albersheim
Susan Albersheim
RERajavel Elango
Rajavel Elango
SISheila M. Innis
Sheila M. Innis
Choline is essential for infant development. Human milk choline is predominately present in three water-soluble choline (WSC) forms: free choline (FC), phosphocholine (PhosC), and glycerophosphocholine (GPC). It is unclear whether mother’s own preterm milk and pooled donor milk differ in WSC composition and whether WSC compounds are interrelated. Mother’s own preterm milk (n = 75) and donor milk (n = 30) samples from the neonatal intensive care unit, BC Women’s Hospital were analyzed for WSC composition using liquid chromatography tandem mass spectrometry (LC-MS/MS). Associations between different WSC compounds were determined using Pearson’s correlations, followed by Fischer r-to-z transformation. Total WSC concentration and concentrations of FC, PhosC, and GPC did not significantly differ between mother’s own milk and donor milk. FC was negatively associated with PhosC and GPC in mother’s own milk (r = −0.27, p = 0.02; r = −0.34, p = 0.003, respectively), but not in donor milk (r = 0.26, p = 0.181 r = 0.37, p = 0.062, respectively). The difference in these associations between the two milk groups were statistically significant (p = 0.03 for the association between PhosC and FC; and p = 0.003 for the association between FC and GPC). PhosC and GPC were positively associated in mother’s own milk (r = 0.32, p = 0.036) but not donor milk (r = 0.36, p = 0.062), although the difference in correlation was not statistically significant. The metabolic and clinical implications of these associations on the preterm infant need to be further elucidated.

5 November 2021 in Science Advances
Verified
Journal Article
Open access
TCToby Candler
Toby Candler
NKNoah J. Kessler
Noah J. Kessler
CGChathura J. Gunasekara
Chathura J. Gunasekara
KWKate A. Ward
Kate A. Ward
PJPhilip James
Philip James
MSMatt Silver
Matt Silver
Child PAX8 methylation is associated with thyroid volume and function and influenced by maternal periconceptional nutrition.