Yes / Here we present a novel method which allows the measurement of the stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) from much smaller samples of dentine than previously possible without affecting the quality parameters. The reconstruction of the diet of past populations using isotopic analysis of bone collagen is a well-established tool. However, because of remodelling of bone throughout life, this gives a blurred picture of the diet. The analysis of δ13C and δ15N from tiny increments of dentine utilizes tissue that does not remodel and permits comparison, at the same age, of those who survived infancy with those who did not at high temporal resolution. This new method has been tested on archaeological teeth from two sites: three molar teeth from the 19th Century Kilkenny Union Workhouse Famine cemetery, Ireland; and three from the Anglian (5-7th centuries AD) cemetery at West Heslerton, Yorkshire, England, selected on the basis of their varied preservation. The methods of incremental dentine sectioning described in Beaumont et al (2013)[1] were carried out and a sub-section removed prior to denaturing and lyophilisation. The two sample sets, dentine and collagen from each section, were measured by isotope ratio mass spectrometry. The profiles produced from each of the six teeth studied show close correlation in isotope ratios indicating that demineralized dentine which has not been denatured and lyophilised produces isotope ratios comparable with dentine collagen. This finding allows analysis of extremely small samples of dentine which could previously not be measured using current instruments and methods.

Yes / Background: stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) in bone and dentine collagen have been used for over 30 years to estimate palaeodiet, subsistence strategy, breastfeeding duration and migration within burial populations. Recent developments in dentine microsampling allow improved temporal resolution for dietary patterns. Aim: We propose a simple method which could be applied to human teeth to estimate chronological age represented by dentine microsamples in the direction of tooth growth, allowing comparison of dietary patterns between individuals and populations. The method is tested using profiles from permanent and deciduous teeth of two individuals. Subjects and methods: using a diagrammatic representation of dentine development by approximate age for each human tooth (based on the Queen Mary University of London Atlas) (AlQahtani et al., 2010), we estimate the age represented by each dentine section. Two case studies are shown: comparison of M1 and M2 from a 19th century individual from London, England, and identification of an unknown tooth from an Iron Age female adult from Scotland. Results and conclusions: The isotopic profiles demonstrate that variations in consecutively-forming teeth can be aligned using this method to extend the dietary history of an individual, or identify an unknown tooth by matching the profiles.

Regulation of metabolism is vital to health and lies at the core of many different diseases. The breakdown of metabolisms' regulation within the brain can lead to neurological disease like Alzheimer's Disease (AD). AD is known to affect brain regions responsible for memory and memory processing like the hippocampus and entorhinal cortex. The regulation of these regions' protein quality, synthesis, and degradation deviate from 'normal' or 'healthy' levels when AD is happening. It is known there is a breakdown of regulation in those regions; however, little is known about the specifics of regulation in healthy brains regions or how it changes with disease. Using the sample collection method of microsampling in combination with kinetic proteomics we investigated proteostasis control in regions known to be affected by AD relative to a control region. This provides a baseline for proteins and ontologies found in the proteomes under healthy circumstances. The regions are all the same tissue type; however, since different regions of the brain perform different functions, the metabolism and therefore the regulation of proteostasis are different. By understanding how regional brain proteomes are regulated in young healthy mice, we are prepared for comparisons against diseased tissue in future work.

No description available.