Combining bleach and mild predigestion improves ancient DNA recovery from bones.

The feasibility of genome-scale studies from archaeological material remains critically dependent on the ability to access endogenous, authentic DNA. In the majority of cases, this represents a few per cent of the DNA extract, at most. A number of specific pre-extraction protocols for bone powder aimed to improve ancient DNA recovery before library amplification have recently been developed. Here, we test the effects of combining two of such protocols, a bleach wash and a predigestion step, on 12 bone samples of Atlantic cod and domestic horse aged 750-1350 cal. years before present. Using high-throughput sequencing, we show that combined together, bleach wash and predigestion consistently yield DNA libraries with higher endogenous content than either of these methods alone. Additionally, the molecular complexity of these libraries is improved and endogenous DNA templates show larger size distributions. Other library characteristics, such as DNA damage profiles or the composition of microbial communities, are little affected by the pre-extraction protocols. Application of the combined protocol presented in this study will facilitate the genetic analysis of an increasing number of ancient remains and will reduce the cost of whole-genome sequencing

Platinum-group elements, S, Se and Cu in highly depleted abyssal peridotites from the Mid-Atlantic Ocean Ridge (ODP Hole 1274A): Influence of hydrothermal and magmatic processes

Highly depleted harzburgites and dunites were recovered from ODP Hole 1274A, near the intersection between the Mid-Atlantic Ocean Ridge and the 15°20′N Fracture Zone. In addition to high degrees of partial melting, these peridotites underwent multiple episodes of melt-rock reaction and intense serpentinization and seawater alteration close to the seafloor. Low concentrations of Se, Cu and platinum-group elements (PGE) in harzburgites drilled at around 35-85 m below seafloor are consistent with the consumption of mantle sulfides after high degrees (>15-20 %) of partial melting and redistribution of chalcophile and siderophile elements into PGE-rich residual microphases. Higher concentrations of Cu, Se, Ru, Rh and Pd in harzburgites from the uppermost and lowest cores testify to late reaction with a sulfide melt. Dunites were formed by percolation of silica- and sulfur-undersaturated melts into low-Se harzburgites. Platinum-group and chalcophile elements were not mobilized during dunite formation and mostly preserve the signature of precursor harzburgites, except for higher Ru and lower Pt contents caused by precipitation and removal of platinum-group minerals. During serpentinization at low temperature (<250 °C) and reducing conditions, mantle sulfides experienced desulfurization to S-poor sulfides (mainly heazlewoodite) and awaruite. Contrary to Se and Cu, sulfur does not record the magmatic evolution of peridotites but was mostly added in hydrothermal sulfides and sulfate from seawater. Platinum-group elements were unaffected by post-magmatic low-temperature processes, except Pt and Pd that may have been slightly remobilized during oxidative seawater alteration

How Do Young Women with Cancer Experience Oncofertility Counselling during Cancer Treatment? A Qualitative, Single Centre Study at a Danish Tertiary Hospital

Background: Adolescents and young adults (AYAs) with cancer are at risk of therapy-induced infertility. The importance of initial and specialized fertility counselling to this patient group is undisputed. Despite international guidelines, oncofertility counselling is still inadequate. The purpose of this study was to examine how female AYA cancer patients and survivors experienced initial and specialized oncofertility counselling, and to present their specific suggestions on how to improve the oncofertility counselling. Methods: Twelve individual semi-structured interviews were performed with AYAs aged 20–35 with cancer or who were survivors. Participants were recruited via a youth support centre and social organization for AYAs with cancer. Data was analysed using thematic analysis. Results: Three main themes were found: Support is needed for navigating the fertility information jungle; The doctor’s approach determines the content of the patient consultation; Inadequate and worrying information causes mistrust and frustration. Conclusion: Results indicate a continuing problem regarding insufficient oncofertility counselling to AYAs with cancer. To ensure adequate and uniform information, especially in the initial oncofertility counselling, national guidelines for oncology specialists are suggested including multidisciplinary effort and collaboration between oncology and fertility specialists in mind. In addition, participants suggest focus on communication skills

Authentication and Assessment of Contamination in Ancient DNA

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