Alien Registration- Tozer, Catherine A. (Lincoln, Penobscot County)

https://digitalmaine.com/alien_docs/7371/thumbnail.jp

The Gut Microbiota Composition in Dichorionic Triplet Sets Suggests a Role for Host Genetic Factors

peer-reviewedMonozygotic and dizygotic twin studies investigating the relative roles of host genetics and environmental factors in shaping gut microbiota composition have produced conflicting results. In this study, we investigated the gut microbiota composition of a healthy dichorionic triplet set. The dichorionic triplet set contained a pair of monozygotic twins and a fraternal sibling, with similar pre- and post-natal environmental conditions including feeding regime. V4 16S rRNA and rpoB amplicon pyrosequencing was employed to investigate microbiota composition, and the species and strain diversity of the culturable bifidobacterial population was also examined. At month 1, the monozygotic pair shared a similar microbiota distinct to the fraternal sibling. By month 12 however, the profile was more uniform between the three infants. Principal coordinate analysis (PCoA) of the microbiota composition revealed strong clustering of the monozygotic pair at month 1 and a separation of the fraternal infant. At months 2 and 3 the phylogenetic distance between the monozygotic pair and the fraternal sibling has greatly reduced and by month 12 the monozygotic pair no longer clustered separately from the fraternal infant. Pulse field gel electrophoresis (PFGE) analysis of the bifidobacterial population revealed a lack of strain diversity, with identical strains identified in all three infants at month 1 and 12. The microbiota of two antibiotic-treated dichorionic triplet sets was also investigated. Not surprisingly, in both triplet sets early life antibiotic administration appeared to be a major determinant of microbiota composition at month 1, irrespective of zygosity. By month 12, early antibiotic administration appeared to no longer exert such a strong influence on gut microbiota composition. We hypothesize that initially host genetics play a significant role in the composition of an individual’s gut microbiota, unless an antibiotic intervention is given, but by month 12 environmental factors are the major determinant.This study was performed as part of the INFANTMET project (10/RD/Infantmet/MFRC/705) and was funded by the Government of Ireland's Department of Agriculture Fisheries and in part by Alimentary Pharmabiotic Centre. KM is a Teagasc Walsh Fellow. CS, RPR and PWOT are members of The Alimentary Pharmabiotic Centre, which is a Centre for Science and Technology (CSET) funded by the Science Foundation Ireland (SFI), through the Irish Government’s National Development Plan (Grant no. 02/CE/B124 and 07/CE/B1368)

Physiological Performance in Full-Sun Vs. Shaded Post-Fire Malosma laurina Seedlings

Post-fire Malosma laurina regenerates both by resprouting and by disseminating seeds. The objective of this study is to assess seedling performance either in full-sunlight or in artificially shaded treatments. By identifying under which conditions Malosma laurina seedlings grow more effectively, one can predict where post-fire M. laurina seedling communities will thrive. The methodology employed throughout this experiment began by covering existing seedlings with shade cloth held by wooden stakes. These treatments were adjacent to full-sun environments; each of which contained at least two Malosma laurina seedlings. Six experimental sites were set up, and the seedlings in question were monitored for growth, conductance, relative humidity, temperature, and light exposure. Water potential was also measured once at each site at the conclusion of the experiment. The results show that seedlings under a shady protection grow taller and transpire less water on average than seedlings that are exposed to full sunlight. The shaded seedlings looked healthier than their full-sun counterparts. It can be concluded that seedlings have better physiological success under shade protection than under full sun

Validity of a two-item physical activity questionnaire for assessing attainment of physical activity guidelines in youth

Background: As physical activity is important for health and well-being, it is essential to monitor population prevalence of physical activity. Surveillance is dependent on the use of valid and reliable measurement tools. The PACE+ questionnaire is used globally in youth and has acceptable reliability; however it has not been validated in a European sample. The purpose of this study is to validate this instrument in a sample of 10-18 year old Irish youth. Methods: Participants (n=419, 45.7 % male) completed the PACE+ two-item questionnaire and were asked to wear an Actigraph accelerometer for eight consecutive days. Freedson cut-points were used to estimate moderate to vigorous physical activity from accelerometer counts. Analyses compared self-report and accelerometry data in participants with (1) ≥5 and (2) seven valid accelerometer days. Calculations were performed for the whole sample, and were stratified by sex and school level (primary; post-primary). Results: Spearman correlations between self-reported physical activity levels and accelerometry derived minutes of moderate-to-vigorous physical activity per day were small (r=0.27; seven valid days) to moderate (r=0.34; ≥5 valid days). Higher correlations were found in older participants (post-primary r=0.39; primary r=0.24) and females (r=0.39; males r=0.27) using ≥5 valid days. The agreement level was high (68-96 %). The accuracy of classifying those not meeting the guidelines (specificity) was moderate to high (59-100 %). Conclusions: The PACE+ self-report instrument has acceptable validity for assessing non-achievement of the adolescent physical activity recommendations. The validity is higher in females and increases with age. The continued use of the tool is recommended and will allow for comparability between studies, tracking of physical activity over time including trends in youth population prevalence

The Composition of Human Milk and Infant Faecal Microbiota Over the First Three Months of Life: A Pilot Study

peer-reviewedHuman milk contains a diverse array of bioactives and is also a source of bacteria for the developing infant gut. The aim of this study was to characterize the bacterial communities in human milk and infant faeces over the first 3 months of life, in 10 mother-infant pairs. The presence of viable Bifidobacterium and Lactobacillus in human milk was also evaluated. MiSeq sequencing revealed a large diversity of the human milk microbiota, identifying over 207 bacterial genera in milk samples. The phyla Proteobacteria and Firmicutes and the genera Pseudomonas, Staphylococcus and Streptococcus were the predominant bacterial groups. A core of 12 genera represented 81% of the microbiota relative abundance in milk samples at week 1, 3 and 6, decreasing to 73% at week 12. Genera shared between infant faeces and human milk samples accounted for 70–88% of the total relative abundance in infant faecal samples, supporting the hypothesis of vertical transfer of bacteria from milk to the infant gut. In addition, identical strains of Bifidobacterium breve and Lactobacillus plantarum were isolated from the milk and faeces of one mother-infant pair. Vertical transfer of bacteria via breastfeeding may contribute to the initial establishment of the microbiota in the developing infant intestine

Effect of Polyphenol Supplementation on Memory Functioning in Overweight and Obese Adults: A Systematic Review and Meta-Analysis

Negative health consequences of obesity include impaired neuronal functioning and celldeath, thus bringing the risk of impaired cognitive functioning. Antioxidant properties of polyphenolsoffer a possible intervention for overweight people, but evidence for their effectiveness in supportingcognitive functioning is mixed. This review examined evidence from randomized controlledtrials concerning the effect of polyphenols on tasks requiring either immediate or delayed retrievalof learned information, respectively, thus controlling for differences in cognitive processes and relatedneural substrates supporting respective task demands. Searches of the PubMed/Medline,PsycInfo, and Scopus databases identified 24 relevant primary studies with N = 2336 participantshaving a BMI ≥ 25.0 kg/m2. The participants’ mean age for the 24 studies exceeded 60 years. Respectivemeta-analyses produced a significant summary effect for immediate retrieval but not for delayedretrieval. The present findings support a potential positive effect of chronic supplementationwith polyphenols, most notably flavonoids, on immediate retrieval in participants aged over 60years with obesity being a risk factor for cognitive impairment. We recommend further investigationof this potential positive effect in participants with such risk factors. Future research on all populationsshould report the phenolic content of the supplementation administered and be specific regardingthe cognitive processes tested

Revisiting Metchnikoff: Age-related alterations in microbiota-gut-brain axis in the mouse

Over the last decade, there has been increased interest in the role of the gut microbiome in health including brain health. This is by no means a new theory; Elie Metchnikoff proposed over a century ago that targeting the gut by consuming lactic acid bacteria such as those in yogurt, could improve or delay the onset of cognitive decline associated with ageing. However, there is limited information characterising the relationship between the behavioural and physiological sequelae of ageing and alterations in the gut microbiome. To this end, we assessed the behavioural, physiological and caecal microbiota profile of aged male mice. Older mice (20–21 months old) exhibited deficits in spatial memory and increases in anxiety-like behaviours compared to younger mice (2–3 months old). They also exhibited increased gut permeability, which was directly correlated with elevations in peripheral pro-inflammatory cytokines. Furthermore, stress exacerbated the gut permeability of aged mice. Examination of the caecal microbiota revealed significant increases in phylum TM7, family Porphyromonadaceae and genus Odoribacter of aged mice. This represents a shift of aged microbiota towards a profile previously associated with inflammatory disease, particularly gastrointestinal and liver disorders. Furthermore, Porphyromonadaceae, which has also been associated with cognitive decline and affective disorders, was directly correlated with anxiety-like behaviour in aged mice. These changes suggest that changes in the gut microbiota and associated increases in gut permeability and peripheral inflammation may be important mediators of the impairments in behavioural, affective and cognitive functions seen in ageing