Citations

Spontaneous intracerebral hemorrhage (sICH) represents a devastating clinical event with high mortality and morbidity rates. Only few patients with sICH are treated with neurosurgical evacuation of the hematoma, and the majority of them need only a good conservative medical approach. The goal of medical treatment is to avoid secondary neurological and systemic complications. Venous thromboembolism (VTE) represents one of the most feared complications of sICH, and it is a potential cause of death. The balance between the benefit of VTE prevention and the risk of hematoma enlargement and/or rebleeding with the use of pharmacologic thromboprophylaxis remains controversial because of the lack of consistent evidences in the literature. The efficacy of mechanical prophylaxis is also uncertain. Consequently, until now there are no clear guidelines and scientific evidences available for physicians in this field. The aim of this review is to analyze the available literature and guidelines about pharmacological VTE prophylaxis in patients with nonsurgical sICH.

The retromer complex, composed of sorting nexin subunits and a Vps26/Vps29/Vps35 trimer, mediates sorting of retrograde cargo from the endosome to the trans-Golgi network. The retromer trimer subcomplex is an effector of Rab7 (Ypt7 in yeast). Whereas endosome targeting of human retromer has been shown to require Rab7-GTP, targeting of yeast retromer to the endosome is independent of Ypt7-GTP and requires the Vps5 and Vps17 retromer sorting nexin subunits. An evolutionarily conserved amino acid segment within Vps35 is required for Ypt7/Rab7 recognition in vivo by both yeast and human retromer, establishing that Rab recognition is a conserved feature of this subunit. Recognition of Ypt7 by retromer is required for its function in retrograde sorting, and in yeast cells lacking the guanine nucleotide exchange factor for Ypt7, retrograde cargo accumulates in endosomes that are decorated with retromer, revealing an additional role for Rab recognition at the cargo export stage of the retromer functional cycle. In addition, yeast retromer trimer antagonizes Ypt7-regulated organelle tethering and fusion of endosomes/vacuoles via recognition of Ypt7. Thus retromer has dual roles in retrograde cargo export and in controlling the fusion dynamics of the late endovacuolar system.