Estrogen-eluting, phosphorylcholine-coated stent implantation is associated with reduced neointimal formation but no delay in vascular repair in a porcine coronary model.

Estrogen can inhibit intimal proliferation and accelerate endothelial regeneration after angioplasty. This suggests that estrogen may prevent in-stent restenosis. Unlike other therapies to prevent restenosis, estrogen may also not delay endothelial regrowth, thereby avoiding the risk of late stent thrombosis. The purpose of this work was to determine the effect of a 17beta-estradiol-eluting stent on neointimal formation in a porcine model. Each artery of six pigs was randomized to either a control, low-dose, or high-dose 17beta-estradiol-eluting stent. All animals were sacrificed at 30 days for histopathological analysis. There was a 40% reduction in intimal area in the high-dose stents compared with control stents (2.54 +/- 1.0 vs. 4.13 +/- 1.1 mm(2), for high dose vs. control, respectively; P < 0.05). There was complete endothelial regeneration at 30 days and similar inflammatory response to stenting on histopathology in all the stent groups. This is the first study to show that 17beta-estradiol-eluting stents are associated with reduced neointimal formation without affecting endothelial regeneration in the pig model of in-stent restenosis. Estrogen-coated stents may have a potential benefit in the prevention and treatment of in-stent restenosis.     

Dedicated two-stent technique in complex bifurcation percutaneous coronary intervention with use of everolimus-eluting stents: The EES-bifurcation study

Objectives

To compare the outcomes of initial one-stent (1S) versus dedicated two-stent (2S) strategies in complex bifurcation percutaneous coronary intervention (PCI) using everolimus-eluting stents (EES).

Background

PCI of true bifurcation lesions is technically challenging and historically associated with reduced procedural success and increased restenosis. Prior studies comparing initial one-stent (1S) versus dedicated two-stent (2S) strategies using first-generation drug-eluting stents have shown no reduction in ischemic events and more complications with a 2S strategy.

Methods

We performed a retrospective study of 319 consecutive patients undergoing PCI at a single referral center with EES for true bifurcation lesions, defined by involvement of both the main vessel (MV) and side branch (SB). Baseline, procedural characteristics, quantitative coronary angiography and clinical outcomes in-hospital and at one year were compared for patients undergoing 1S (n = 175) and 2S (n = 144) strategies.

Results

Baseline characteristics were well-matched. 2S strategy was associated with greater SB acute gain (0.65 ± 0.41 mm vs. 1.11 ± 0.47 mm, p < 0.0001). In-hospital serious adverse events were similar (9% with 2S vs. 8% with 1S, p = 0.58). At one year, patients treated by 2S strategy had non-significantly lower rates of target vessel revascularization (5.8% vs. 7.4%, p = 0.31), myocardial infarction (7.8% vs. 12.2%, p = 0.31) and major adverse cardiovascular events (16.6% vs. 21.8%, p = 0.21).

Conclusion

In this study of patients undergoing PCI for true coronary bifurcation lesions using EES, 2S strategy was associated with superior SB angiographic outcomes without excess complications or ischemic events at one year.     

Intracranial hemorrhage pattern in the patients with factor XIII deficiency

Intracranial hemorrhage (ICH) is one of the most severe and life-threatening manifestations occurring in the patients with factor XIII (F XIII) deficiency. The aim of this study was to describe the ICH pattern in the patients suffering from F XIII deficiency. In this case series, we investigated 38 patients with severe F XIII deficiency in south of Iran from January to May 2012. ICH pattern, neurologic complications, efficacy of treatment, and incidence of recurrence were reported. The site of ICH was intraparenchymal in 35 patients (92.1 %), subdural in 2 patients (5.2 %), and epidural hemorrhage in 1 patient (2.6 %). Besides, neurologic complications occurred in 21 patients (55.2 %), including locomotor disability in 8, psychological impairment in 7, mental disorders in 5, speech impairment in 4, and visual impairment in 2. Prophylaxis was started with a dose of 10 IU/kg Fibrogammin every 4–6 weeks for all the patients, except for one. All the patients on prophylaxis showed good response without any episodes of recurrence, except for one. The most frequent site of ICH in our patients was intraparenchymal. It seems that long-term prophylactic treatment with a dose of 10 IU/kg Fibrogammin could be effective in the prevention of CNS bleeding in the patients with F XIII deficiency. Moreover, all the patients with severe F XIII deficiency even without severe bleeding symptoms are recommended to undergo prophylactic treatment.     

Fabrication and performance evaluation of new nanocomposite membranes based on sulfonated poly(phthalazinone ether ketone) for PEM fuel cells

The purpose of this work is to enhance the proton conductivity and fuel cell performance of sulfonated poly(phthalazinone ether ketone) (SPPEK) as a proton exchange membrane through the application of SrTiO₃ perovskite nanoparticles. Nanocomposite membranes based on SPPEK and SrTiO₃ perovskite nanoparticles were prepared via a casting method. The highest proton conductivity of nanocomposite membranes obtained was 120 mS cm⁻¹ at 90 °C and 95% RH. These enhancements could be related to the hygroscopic structure of SrTiO₃ perovskite nanoparticles and the formation of hydrogen bonds between nanoparticles and water molecules. The satisfactory power density, 0.41 W cm⁻² at 0.5 V and 85 °C, of the nanocomposite membrane (5 wt% content of nanoparticles) confirms their potential for application in the PEM fuel cells.

The purpose of this work is to enhance the proton conductivity and fuel cell performance of sulfonated poly(phthalazinone ether ketone) (SPPEK) as a proton exchange membrane through the application of SrTiO₃ perovskite nanoparticles.     

Two-piece implants with turned versus microtextured collars

Implant companies have been promoting two-piece implants with microtextured collars in the interest of hard tissue preservation and/or soft tissue integration. However, this rationale may not be justified. Based on comparative studies currently available, it is unclear whether microroughened implant necks reduce crestal bone loss. A possible effect may be overruled by the establishment of a biologic width or by other factors influencing crestal bone remodeling. In addition, the orientation and attachment of the collagen fibers in the peri-implant mucosa are a little different because the surface roughness varies at the level of the implant neck. The clinician should be cautious when using these modified implants because the impact of microtextured collars on the initiation and progression of peri-implant pathology is currently unknown.