ABSTRACT
AIM: Recanalization of long segmental occlusions of femoropopliteal arteries can be achieved by angioplasty and implantation of nitinol stents with high procedural success rates. However, due to recurrent in-stent restenoses (ISR) some patients need repeated interventions and their intermediate success rates are uncertain. METHODS: Patients who were treated in our center from March 2008 through February 2011 due to symptomatic ISR (as determined by Duplex sonography) were retrospectively included in the study. After endovascular treatment of their ISR, they were prospectively evaluated with regard to recurrent ISR of the target lesions. RESULTS: A total of 36 limbs (=lesions) in 32 patients (69% male, mean age 69±9 years) were successfully treated by balloon-angioplasty. Adjunctive cutting balloons and drug eluting balloons were used in 78% and 8%, respectively. Mean follow-up was 326 days. Recurrent ISR occurred in 10 (28%) lesions, while 26 (78%) lesions showed no recurrence of ISR. In a multivariate logistic regression analysis, age, gender, cardiovascular risk factors, renal failure and medication with cilostazol were not significantly associated with recurrent ISR. Moreover, the number of previous interventions of the target lesions was not an independent predictor of recurrent ISR. CONCLUSION: Patients with multiple recurrences of ISR seem to have the same prospects of acute and mid-term success for endovascular treatment as those with first presentation of ISR. However, this observation has to be confirmed by prospective, large scale studies with a longer follow-up period to determine the significance of endovascular intervention within the scope of different revascularization approaches for treatment of recurrent ISR.
Subject(s)
Angioplasty, Balloon/adverse effects , Femoral Artery/pathology , Peripheral Arterial Disease/surgery , Popliteal Artery/pathology , Aged , Alloys , Constriction, Pathologic , Drug-Eluting Stents , Female , Femoral Artery/surgery , Humans , Logistic Models , Lower Extremity/blood supply , Male , Middle Aged , Multivariate Analysis , Popliteal Artery/surgery , Recurrence , Retrospective Studies , Risk Factors , Vascular Patency/drug effectsABSTRACT
The epithelial cells of the choroid plexus are the structural basis of the blood-cerebrospinal fluid (CSF)-barrier. Here we summarise our recent efforts to culture those cells mainly on permeable supports in vitro. Isolated from porcine brains, we report a simple protocol for the primary culture using cytosine arabinoside as an additive that is cytotoxic for other cells except the plexus epithelial cells. Enhanced barrier properties are obtained by withdrawal of serum from the culture medium after confluency is reached. Cells improve their polarity, permeability for hydrophilic substrates is lowered, electrical resistance is increased tenfold, and a pH-gradient is built up across the cell monolayer. Polarised secretion of proteins and most importantly fluid secretion into the apical filter compartment was attained and proven to be dependent on the Na(+),K(+)-ATPase activity. Active transport processes (penicillin G, riboflavin, myo-inositol, ascorbic acid) were studied and clearly showed the involvement of the organic anion transporter. The permeability of the barrier was found to be regulated by cyclic adenosine monophosphate (cAMP). Moreover, we report that cell proliferation and differentiation is controlled by components of the extracellular matrix. The present culture model could now be used as an in vitro system to quantify drug transport across the blood-CSF-barrier.
