Analysis of clinical features of painless aortic dissection.

The clinical characteristics of painless aortic dissection were investigated in order to improve the awareness of diagnosis and treatment of atypical aortic dissection. The 482 cases of aortic dissection were divided into painless group and pain group, and the data of the two groups were retrospectively analyzed. The major clinical symptom was pain in 447 cases (92.74%), while 35 patients (7.26%) had no typical pain. The gender, age, hypertension, hyperlipidemia, diabetes, smoking and drinking history had no statistically significant differences between the two groups (P>0.05). The proportion of Stanford type A in painless group was significantly higher than that in pain group (48.57% vs. 21.03%, P=0.006). The incidence of unconsciousness in the painless group was significantly higher than that in the pain group (14.29% vs. 3.58%, P=0.011). The incidence of hypotension in painless group was significantly higher than that in pain group for 4.26 folds (P=0.01). Computed tomography angiography (CTA) examination revealed that the incidence of aortic arch involved in the painless group was significantly higher than that in the pain group (19.23% vs. 5.52%, P=0.019). It was concluded that the incidence of painless aortic dissection was higher in Stanford A type patients, commonly seen in the patients complicated with hypotension and unconsciousness. CTA examination revealed higher incidence of aortic arch involvement.

Role of tetraspanin CD151-α3/α6 integrin complex: Implication in angiogenesis CD151-integrin complex in angiogenesis.

Tetraspanin CD151 mainly associates with laminin-binding integrins and forms CD151-integrin complex. We previously reported that CD151 could be a potential target for angiogenesis, but the mechanisms involved are still unclear. This study investigated the role of CD151-integrin complex in angiogenesis and the signaling mechanisms involved. Here we showed that CD151 and CD151-AAA mutant were both well expressed at the protein level. CD151 gene transfer promoted angiogenesis and improved skin temperature of the lateral ischemic hindlimb, whereas CD151-AAA mutant abrogated the increase in capillary density and skin temperature. Further, CD151-AAA mutant failed to activate the FAK, ERK, PI3K/Akt/eNOS, and Rac1/Cdc42 signaling pathways. Moreover, CD151-AAA mutant was unavailable to promote bovine aortic endothelial cells (BAECs) proliferation and migration, in contrast to the effects of CD151. The results suggested that formation of CD151-integrin complex was likely to be a prerequisite for CD151-induced angiogenesis and signaling pathways.