Mark Lewis/netrf.org
Aug 18, 2025, 09:45
Mark Lewis: aPTT Pathway—What Activates What
Mark Lewis, Director of Gastrointestinal Oncology at Intermountain Healthcare in Utah, shared a post X:
“So factor XII is activated when it’s exposed to collagen, kallikrein, and high molecular weight kininogen, which in turn activates factor XI into XIa. With a calcium ion, factor XIa activates factor IX. Then, FIXa, FVIIIa, and calcium activate factor X…”

Stay in tune with Hemostasis Today.
-
Nov 27, 2025, 16:00Nathan Connell on WFH AI Summaries from the Global Forum
-
Nov 27, 2025, 15:49Piotr Czempik: Rethinking Coagulation in Acute Liver Dysfunction
-
Nov 27, 2025, 15:35Overwhelmed? A Leader’s Guide from Mark Crowther to Getting Back on Track
-
Nov 27, 2025, 15:10Wolfgang Miesbach’s Top 10 Picks for TTP and Thrombosis from ASH 2025
-
Nov 27, 2025, 14:24ICCBBA’s Executive Director Eoin McGrath Chairs a Dynamic Session on AI, Innovation and Informatics in Transfusion Medicine
-
Nov 27, 2025, 13:26Wolfgang Miesbach’s Top 10 Picks for Bleeding Disorders from ASH 2025
-
Nov 27, 2025, 11:19Priya Prasad Presents a Case of Severe Hypotensive Transfusion Reaction
-
Nov 27, 2025, 04:07Eugene Tang Presents Highlights from UK Stroke Forum 2025
-
Nov 27, 2025, 03:47Michael Makris: I Believe the Time Has Come to Consider Emicizumab Up Front in Persons with Acquired Hemophilia
