Comparing biogenic blue mussel (<i>Mytilus edulis</i>) reef definitions in Northern Europe: implications for management and conservation

To combat biodiversity loss, the European Union (EU) established a network of protected areas to be implemented by 2000, termed Natura 2000 (N2000). However, several N2000 sites remain unmapped, and various habitats remain undefined. Delayed implementation allows continued habitat degradation and biodiversity loss. Targeting biogenic reefs by blue mussels (Mytilus edulis and Mytilus trossulus), this study 1) compared blue mussel reef definitions across EU member states surrounding the North Sea and Baltic Sea, 2) scrutinized biological mechanisms underpinning the habitat definitions, and 3) provided suggestions for harmonized habitat definitions, respecting spatial and biological variation. By comparing official definitions of blue mussel reefs applied in Denmark, Sweden, The United Kingdom, and Germany, this study revealed A) decadal delay in implementation, B) reef definitions varying significantly regarding number of parameters used for identification (e.g., mussel seabed area (m2), and proportion seabed mussel coverage (%)) and the associated parameter limits (e.g., 2.500 m2, and 30%, respectively). Specifically, parameter limits for identification of reefs range between 1 and 10,000 m2 for mussel area and between 5% and 30% seabed mussel coverage. The study failed to identify biological mechanisms justifying this variation. Variable habitat definitions, unjustified by biological and spatial variation, may result in uneven protection levels across borders, potentially compromising connectivity of the N2000 network. To avoid this scenario, our study highlights the need for compatible biogenic reef definitions reflecting spatial and biological properties and suggests moving from protection of individual reefs to protection of areas where habitat forming blue mussels are regularly occurring

Treatment-free remission after a second TKI discontinuation attempt in patients with Chronic Myeloid Leukemia re-treated with dasatinib – interim results from the DAstop2 trial

Tyrosine kinase inhibitor (TKI) discontinuation in chronic myeloid leukemia (CML) has become part of routine care for patients with a sustained deep molecular response (DMR). Approximately 50% experience a molecular relapse upon TKI cessation. Most of them quickly regain DMR upon TKI resumption. Whether these patients can achieve a second treatment-free remission (TFR) remains unclear. DAstop2 (ClinicalTrials.gov ID: NCT03573596) is a prospective study including patients with a failed first TFR attempt re-treated with any TKI for ≥ one year. Upon entering the study, patients received the TKI dasatinib for additional two years. Patients with sustained DMR for ≥1 year qualified for a second TKI stop. Ninety-four patients were included between Oct 2017-Dec 2021. At the time of data analysis, 62 patients had attempted a 2nd stop. After a median follow-up of 27 months from 2nd stop, TFR rates were 61, 56 and 46% at 6, 12 and 24 months respectively. No progression to advanced stage disease was seen and 87% had re-achieved MR4 within a median of 3 months from TKI re-initiation. In summary, we show that a 2nd TFR attempt after dasatinib treatment is safe, feasible and TFR rates seem in the range of those reported in trials of a first TKI stop.Peer reviewe