Biology subjects

Hamilton, D.

Publications and source records attributed to Hamilton, D..

4 recordsLinked to original sources

bioRxiv2026

Ancient DNA reveals matrilineal organisation and recurrent unions between dominant matrilines in Iron Age Britain

Kinship practices underpin all traditional societies, forming the basis for socially sanctioned reproductive unions, residence patterns and the inheritance of rights and property1,2. Although the relationship between biological relatedness and kinship is not always straightforward, ancient DNA studies are increasingly used to examine the extent to which biological relatedness underpinned social constructs of kinship in prehistoric societies3-6. Here, we report the analysis of genome-wide data for 534 individuals from the Arras Culture of Middle Iron Age northeast England (including 390 from Wetwang Slack, 100 from Pocklington, and 29 from Melton), finding evidence for communities with kinship systems structured along matrilineal lines. At Wetwang Slack, we reconstruct a 13-generation pedigree comprising 195 individuals structured around female-line connections: matrilineal transmissions greatly outnumbered patrilineal ones and male reproductive partners were largely absent from the cemetery, plausibly because they were buried in their own natal communities. Furthermore, the three main sites with robust sample sizes were characterised by non-overlapping dominant mitochondrial haplogroups, implying a maternal clan-based structure. Reproductive unions at Wetwang Slack suggest a recurrent alliance between two dominant maternal descent groups, with members of each group never reproducing with members of their own maternal lineage. Meanwhile, three individuals from lavishly furnished chariot burials at Wetwang Slack were close maternal relatives belonging to a lineage with consecutive generations of close kin unions, a pattern largely absent among other individuals at the site. These results indicate highly distinctive social practices among an elite group embedded in the wider kinship network of the Arras community.

genetics↗

bioRxiv2021

MSM and sesame seed oil improve hyperlipidemia and PUFA metabolism in the db/db mouse

BackgroundAn estimated 463 million people worldwide suffer from diabetes, and that number is projected to rise significantly to 700 million by 2045. One of the hallmarks of type 2 diabetes and metabolic syndrome is alterations in the lipid profile and polyunsaturated fatty acid metabolism. ObjectiveThe objective of this study was to identify lipid alterations in leptin receptor deficient db/db mice, a type 2 diabetes model, to establish a baseline biological signature for the evaluation of natural products with purported lipid-altering activity. MethodsSix-week old male db/db mice (n = 10/group) were randomized to the following groups: 1) diabetic control with no treatment, 2) methylsulfonylmethane (MSM) treatment (3.81 {+/-} 0.33 g/kg), 3) sesame seed oil (SSO) treatment (23.54 {+/-} 2.91 mg/kg), and 4) MSM and SSO combination treatment, receiving the same dosages of MSM and SSO as the single treatment groups. Eight-week old male C57BL6/J mice (n=10) were used as a non-diabetic control group. ResultsSerum triglycerides and total cholesterol were significantly increased in the db/db model compared to nondiabetic control, mimicking diabetes in people. High-density lipoprotein (HDL) was significantly increased in all db/db treatment groups, with the most significant effect in the MSM and SSO combination group, with a corresponding decrease in non-HDL cholesterol. Serum total polyunsaturated fatty acid (PUFA) levels were significantly reduced in diabetic mice compared with control mice. In contrast, treatment with SSO alone reversed this effect such that fed mice exhibited serum PUFA levels comparable to control mice. ConclusionsTreatment of db/db mice with MSM and SSO improved commonly measured clinical parameters in serum lipid panels. The combination of MSM and SSO treatments effects on HDL and non-HDL cholesterol and fatty acid metabolism could lead to improved clinical outcomes in diabetics, such as reduced incidence of atherosclerosis and hepatic steatosis.

pharmacology and toxicology↗

bioRxiv2020

Detection of Prenatal Alcohol Exposure Using Machine Learning Classification of Resting-State Functional Network Connectivity Data

IntroductionPrevious work utilizing resting state fMRI to measure functional network connectivity in rodents with moderate prenatal alcohol exposure (PAE) revealed several sex- and region-dependent alterations in FNC implicating FNC as potential biomarker for PAE. Given that FNC is sensitive to neurological and psychiatric conditions in humans, here, we explore the use of previously acquired FNC data and machine learning methods to detect PAE among a sample of rodents exposed to moderate PAE and controls exposed to a saccharin solution. Materials & MethodsWe utilized previously acquired fMRI data from 48 adult rats 24 PAE (12 male 12 female) and 24 saccharin exposed (SAC) controls (12 male and 12 female) for classification. The entire data sample was utilized to perform binary classification (SAC or PAE) of FNC data with multiple support vector machine (SVM) kernels and out-of-sample cross-validation to evaluate classification performance. ResultsResults revealed accuracy rates of 62.5% for all samples, 58.3% for males, and 79.2% for females using a quadratic SVM kernel to classify moderate PAE from FNC data. In addition, brain networks localized to hippocampal and cortical regions contributed strongly to QSVM classifications. ConclusionOur results suggest overall modest classification performance of a QSVM to detect moderate PAE from FNC data gathered from adult rats, yet good performance among females. Further developments and refinement of the technique hold promise for the detection of PAE in earlier developmental time periods that potentially offer additional tools for the non-invasive detection of PAE from FNC data. IMPACT STATEMENTThe diagnosis of fetal alcohol spectrum disorders (FASDs) can be challenging in individuals who lack the hallmark facial dysmorphologies associated with heavy prenatal alcohol exposure (PAE). The absence of a diagnosis prevents individuals with PAE from receiving the treatment and services that improves quality of life outcomes. This research explores the use of preclinical functional network connectivity data and machine learning techniques as a novel and non-invasive means of detecting PAE. Our aim is to contribute basic science towards improving diagnostic strategies that can lead to securing timely and appropriate support for individuals with FASD and their caregivers.

neuroscience↗

bioRxiv2020

Multi-proxy evidence for the impact of the Storegga Slide Tsunami on the early Holocene landscapes of the southern North Sea

Doggerland was a land mass occupying an area currently covered by the North Sea until marine inundation took place during the mid-Holocene, ultimately separating the British land mass from the rest of Europe. The Storegga Slide, which triggered a tsunami reflected in sediment deposits in the Northern North Sea, North East coastlines of the British Isles and across the North Atlantic, was a major event during this transgressive phase. The spatial extent of the Storegga tsunami however remains unconfirmed because to date no direct evidence for the event has been recovered from the southern North Sea. We present evidence that Storegga associated deposits occur in the southern North Sea. Palaeo-river systems have been identified using seismic survey in the southwestern North Sea and sedimentary cores extracted to track the Mid Holocene inundation. At the head of one palaeo-river system near the Outer Dowsing Deep, the Southern River, we observed an abrupt and catastrophic inundation stratum. Based on lithostratigraphic, macro and microfossils and sedimentary ancient DNA (sedaDNA) evidence, supported by optical stimulation luminescence (OSL) and radiocarbon dating, we conclude these deposits were a result of the Storegga event. Seismic identification of this stratum to adjacent cores indicated diminished traces of the tsunami, largely removed by subsequent erosional processes. Our results demonstrate the catastrophic impact of Storegga within this area of the Southern North Sea, but indicate that these effects were temporary and likely localized and mitigated by the dense woodland and topography of the area. We conclude clear physical remnants of the wave are likely to be restricted to inland basins and incised river valley systems.

paleontology↗