Adipose-derived stem cell/FGF19-loaded microfluidic hydrogel microspheres for synergistic restoration of critical ischemic limb

The efficacy of stem cell therapy is substantially compromised due to low cell survival rate and poor local retention post-delivery. These issues drastically limit the application of stem cells for ischemic limb therapy, which requires effective blood perfusion and skeletal muscle regeneration. Herein, based on microfluidic technology, an integrated stem cell and cytokine co-delivery system designed for functional ischemic limb salvage was constructed by first incorporating the myogenic cytokine, fibroblast growth factor 19 (FGF19), into microspheres composed of methacrylate gelatin (GelMA). Then adipose-derived stem cells (ADSCs) were highly absorbed into the porous structure of the microspheres, overcoming the insufficient loading efficiency and activities by conventional encapsulation strategy. The fabricated ADSCs/FGF19@μsphere system demonstrated a uniform size of about 180 μm and a highly porous structure with pore sizes between 20 and 40 μm. The resultant system allowed high doses of ADSCs to be precisely engrafted in the lesion and to survive, and achieved sustained FGF19 release in the ischemic region to facilitate myoblast recruitment and differentiation and myofibrils growth. Furthermore, the combination of ADSCs and FGF19 exhibited a positive synergistic effect which substantially improved the therapeutic benefit of angiogenesis and myogenesis, both in vitro and in vivo. In summary, a stem cell and cytokine co-delivery system with the properties of easy preparation and minimal invasiveness was designed to ensure highly efficient cell delivery, sustained cytokine release, and ultimately realizes effective treatment of ischemic limb regeneration.

Minimal vessel area predicts in-stent restenosis in nonthrombotic iliac vein compression syndrome after stenting

To the Editor:Iliac vein compression syndrome(IVCS)is a well-documented anatomic abnormality characterized by the compression of iliac veins from the adjacent artery and vertebra.Depending on whether deep vein thrombosis was co-existing,IVCS could be classified into thrombotic and nonthrombotic lesions.Endovascular procedures have become the mainstream treatment for nonthrombotic IVCS.[1]In most cases.

Long-term outcomes following exclusive use of endovascular aortic repair for ruptured infrarenal abdominal aortic aneurysms

To the Editor:Ruptured abdominal aortic aneurysm(rAAA)is a fatal disease.Emergency surgery is the only way to provide an opportunity for survival.In 1994,endovascular aortic repair(EVAR)was reported as an emergency treatment for rAAA.Compared with traditional open surgery(OS),patients could benefit from its lower perioperative mortality and minimal invasiveness.Although recent guidelines have recommended an EVARfirst approach if suitable as judged by the clinician,the standard of whether to give a priority to EVAR varies among clinicians in practical applications,because hostile aortic morphology and hemodynamic conditions were thought to weaken the benefit of EVAR.Hence,controversies still exist regarding whether EVAR as a priority is applicable to most rAAAs.In addition,a search of the literature found few population-based studies with long-term outcomes.Given this,a population-based study was conducted by Zhongshan Hospital,Fudan University.

A balloon-supported embolism protection technique during vertebral/ subclavian artery angioplasty stenting

With high rates of morbidity and mortality,posterior circulation stroke accounts for 20% of ischemic strokes,and approximately 25% occurs in patients with stenosis in the vertebral and/or basilar arteries.liiOn the other hand,the risk of posterior circulation ischemic stroke reaches 30% in patients with symptomatic vertebral artery(VA)stenosis afterSyears,[2]subclavian artery(SA)occlusion,although with a low prevalence in the general population,is also an important causeof posterior circulation stroke.