Spontaneous retroperitoneal hematoma associated with iliac vein rupture

ObjectiveSpontaneous retroperitoneal hematoma (SRH) associated with iliac vein rupture is a rare but life-threatening emergency with high operative mortality. This study summarizes our experience in providing diagnostic and therapeutic management for this rare clinical entity.MethodsBetween May 2002 and May 2009, nine patients were admitted to our hospital for SRH and acute deep venous thrombosis (DVT). Medical data for demographics, clinical presentation, auxiliary examinations, treatment modalities, outcomes, and follow-up were retrospectively analyzed.ResultsNine patients (8 women, 1 man) were enrolled in this study. All were aged >45 years (range, 46-70 years). The common clinical manifestations were sudden onset of left lower abdominal or lumbar pain, swelling of the left lower extremity, anemia, and hypotension. Most patients were diagnosed by duplex ultrasound imaging and computed tomography scan. Three patients were treated conservatively, and six underwent surgical or combined treatments, comprising 2 repairs of iliac vein, 1 iliac vein ligation and Palma-Dale bypass graft, 1 pelvic vein ligation, 1 removal of hematoma, and 1 repair of iliac vein, thrombectomy, and endovascular stent placement. The iliac vein ruptured in five patients. May-Thurner syndrome was found in three patients. One patient died after surgery (operative mortality, 16.7%). Postoperative morbidity was 50%. Mean volume of perioperative blood transfusion was 900 ± 640 mL (range, 0-2000 mL). Mean lengths of stay were 2.7 ± 1.4 days (range, 2-5 days) in the intensive care unit and 16.9 ± 2.4 days (range, 14-21 days) in the hospital. Eight patients were postoperatively treated with 6 months of warfarin. Mean follow-up was 30.5 ± 15.0 months (range, 6-50 months). The occurrence rate of chronic venous insufficiency was 87.5% during follow-up.ConclusionsSRH with concomitant DVT, especially in women aged >45, should be considered in patients with sudden lower abdominal or lumbar pain, leg swelling, anemia, and shock. Spontaneous iliac vein rupture and the presence of May-Thurner syndrome should be considered in these patients. Surgical interventions were associated with high mortality and morbidity. In our experience, conservative therapy was safer than open surgical procedures

Endovascular stent-graft placement and coil embolization for an anomalous splenic artery aneurysm

Aneurysms of the splenic artery originating anomalously from the superior mesenteric artery are extremely rare; however, they are clinically important because of the potential for fatal rupture and particular anatomical location. Most previous cases were managed by open surgical intervention. We present a case of an anomalous splenic artery aneurysm, which was successfully treated with endovascular stent graft placement and coil embolization. This appears to be a promising minimally invasive approach to manage this rare entity. Also, we review the literature of aneurysms of the splenic artery arising from the superior mesenteric artery

Transdifferentiated Human Vascular Smooth Muscle Cells are a New Potential Cell Source for Endothelial Regeneration

Endothelial dysfunction is widely implicated in cardiovascular pathological changes and development of vascular disease. In view of the fact that the spontaneous endothelial cell (EC) regeneration is a slow and insufficient process, it is of great interest to explore alternative cell sources capable of generating functional ECs. Vascular smooth muscle cell (SMC) composes the majority of the vascular wall and retains phenotypic plasticity in response to various stimuli. The aim of this study is to test the feasibility of the conversion of SMC into functional EC through the use of reprogramming factors. Human SMCs are first dedifferentiated for 4 days to achieve a vascular progenitor state expressing CD34, by introducing transcription factors OCT4, SOX2, KLF4 and c-MYC. These SMC-derived progenitors are then differentiated along the endothelial lineage. The SMC-converted ECs exhibit typical endothelial markers expression and endothelial functions in vitro, in vivo and in disease model. Further comprehensive analysis indicates that mesenchymal-to-epithelial transition is requisite to initiate SMCs reprogramming into vascular progenitors and that members of the Notch signalling pathway regulate further differentiation of the progenitors into endothelial lineage. Together, we provide the first evidence of the feasibility of the conversion of human SMCs towards endothelial lineage through an intermediate vascular progenitor state induced by reprogramming.British Heart Foundation [RG/14/6/31144, RM/13/2/30158]; Oak Foundation; International Cooperation and Exchanges NSFC [81220108004]; China Scholarship CouncilSCI(E)ARTICLE

HDAC3 is crucial in shear- and VEGF-induced stem cell differentiation toward endothelial cells

Reendothelialization involves endothelial progenitor cell (EPC) homing, proliferation, and differentiation, which may be influenced by fluid shear stress and local flow pattern. This study aims to elucidate the role of laminar flow on embryonic stem (ES) cell differentiation and the underlying mechanism. We demonstrated that laminar flow enhanced ES cell–derived progenitor cell proliferation and differentiation into endothelial cells (ECs). Laminar flow stabilized and activated histone deacetylase 3 (HDAC3) through the Flk-1–PI3K–Akt pathway, which in turn deacetylated p53, leading to p21 activation. A similar signal pathway was detected in vascular endothelial growth factor–induced EC differentiation. HDAC3 and p21 were detected in blood vessels during embryogenesis. Local transfer of ES cell–derived EPC incorporated into injured femoral artery and reduced neointima formation in a mouse model. These data suggest that shear stress is a key regulator for stem cell differentiation into EC, especially in EPC differentiation, which can be used for vascular repair, and that the Flk-1–PI3K–Akt–HDAC3–p53–p21 pathway is crucial in such a process

Electro-osmotic consolidation of soil with variable compressibility, hydraulic conductivity and electro-osmosis conductivity

In present study, the non-linear variations of soil compressibility, hydraulic and electro-osmosis conductivities were analyzed through laboratory experiments, and incorporated in a one-dimensional model. The analytical solutions for excess pore water pressure and degree of consolidation were derived, and numerical simulations were performed to verify its effectiveness. The results indicated that both the non-linear variations of hydraulic and electro-osmosis conductivities showed remarkable impacts on the excess pore water pressure and degree of consolidation, especially for soils with relative high compressibility. A further comparison with previous analytical solutions indicated that more accurate predictions could be obtained with the proposed analytical solutions. (C) 2016 Elsevier Ltd. All rights reserved