72 research outputs found

    Demographic reconstruction from ancient DNA supports rapid extinction of the great auk

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    The great auk was once abundant and distributed across the North Atlantic. It is now extinct, having been heavily exploited for its eggs, meat, and feathers. We investigated the impact of human hunting on its demise by integrating genetic data, GPS-based ocean current data, and analyses of population viability. We sequenced complete mitochondrial genomes of 41 individuals from across the species’ geographic range and reconstructed population structure and population dynamics throughout the Holocene. Taken together, our data do not provide any evidence that great auks were at risk of extinction prior to the onset of intensive human hunting in the early 16th century. In addition, our population viability analyses reveal that even if the great auk had not been under threat by environmental change, human hunting alone could have been sufficient to cause its extinction. Our results emphasise the vulnerability of even abundant and widespread species to intense and localised exploitation

    Phase I Study of Everolimus, Cetuximab and Irinotecan as Second-line Therapy in Metastatic Colorectal Cancer

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    AIM: To evaluate feasible doses of weekly everolimus and irinotecan given with cetuximab for previously treated metastatic colorectal cancer (mCRC). PATIENTS AND METHODS: Adults with mCRC that progressed after 5-fluorouracil or capecitabine-plus-oxaliplatin were treated using a sequential dose escalation scheme. Dosing decisions were based on the probability of experiencing a dose-limiting toxicity (DLT) during the first two 21-day treatment cycles. RESULTS: Patients received everolimus 30 mg/week plus irinotecan 350 mg/m(2) q3w (n=5; dose A1) or everolimus 30 mg/week plus irinotecan 250 mg/m(2) q3w (n=14; dose B1). Among patients evaluable for the maximum tolerated dose, two out of four in A1 and one out of eight in B1 experienced four DLTs. The trial was terminated early based on changes in clinical practice and emerging data on everolimus dosing. CONCLUSION: The feasible doses of everolimus and irinotecan administered with cetuximab as second-line therapy in mCRC were 30 mg/week and 250 mg/m(2), respectively
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