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1.
J Hosp Infect ; 106(3): 465-472, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32810570

ABSTRACT

BACKGROUND: The introduction of antimicrobial surfaces into healthcare environments is believed to impact positively on the rate of healthcare-associated infections by significantly decreasing pathogen presence on surfaces. AIM: To report on a novel efficacy test that uses a dry bacterial inoculum to measure the microbicidal efficacy of antimicrobial surfaces. METHODS: An aerosolized dry inoculum of Staphylococcus aureus or Acinetobacter baumannii was deposited on copper alloy surfaces or a hospital-grade stainless-steel surface. Surviving bacteria were enumerated following incubation of the inoculated surfaces at an environmentally relevant temperature and relative humidity. Damage caused to bacteria by the aerosolization process and by the different surfaces was investigated. FINDINGS: Dry inoculum testing showed a <2-log10 reduction in S. aureus or A. baumannii on the copper alloy surfaces tested after 24 h at 20°C and 40% relative humidity. Potential mechanisms of action included membrane damage, DNA damage and arrested cellular respiration. The aerosolization process caused some damage to bacterial cells. Once this effect was taken into account, the antimicrobial activity of copper surfaces was evident. CONCLUSIONS: Our test provided a realistic deposition of a bacterial inoculum to a surface and, as such, a realistic protocol to assess the efficacy of dry antimicrobial environmental surfaces in vitro.


Subject(s)
Aerosols/pharmacology , Alloys , Bacteria/drug effects , Coated Materials, Biocompatible/standards , Copper/pharmacology , Microbial Viability , Acinetobacter baumannii/drug effects , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Cross Infection/microbiology , Cross Infection/prevention & control , Freeze Drying , Humidity , Staphylococcus aureus/drug effects , Surface Properties , Temperature
3.
IET Nanobiotechnol ; 13(8): 816-823, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31625521

ABSTRACT

Several materials such as silver are used to enhance graphene oxide (GO) sheets antimicrobial activity. However, these toxic materials decrease its biocompatibility and hinder its usage in many biological applications. Therefore, there is an urgent need to develop nanocomposites that can preserve both the antimicrobial activity and biocompatibility simultaneously. This work highlights the importance of functionalisation of GO sheets using Polyvinylpyrrolidone (PVP) and decorating them with silver nanoparticles (AgNPs) in order to enhance their antimicrobial activity and biocompatibility at the same time. The structural and morphological characterisations were performed by UV-Visible, Fourier transform infrared (FTIR), and Raman spectroscopic techniques, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HR-TEM). The antimicrobial activities of the prepared samples against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans were studied. The cytotoxicity of prepared materials was tested against BJ1 normal skin fibroblasts. The results indicated that the decoration with AgNPs showed a significant increase in the antimicrobial activity of GO and FGO sheets, and functionalisation of GO sheets and GO-Ag nanocomposite with PVP improved the cell viability about 40 and 35%, respectively.


Subject(s)
Coated Materials, Biocompatible/chemical synthesis , Graphite/chemistry , Metal Nanoparticles/chemistry , Nanocomposites/chemistry , Povidone/chemistry , Silver/chemistry , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Candida albicans , Cells, Cultured , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Coated Materials, Biocompatible/standards , Fibroblasts/cytology , Fibroblasts/drug effects , Fibroblasts/physiology , Graphite/pharmacology , Humans , Materials Testing , Metal Nanoparticles/standards , Microbial Sensitivity Tests , Nanocomposites/standards , Povidone/pharmacology , Pseudomonas aeruginosa , Quality Improvement , Silver/pharmacology , Skin/cytology , Skin/drug effects , Staphylococcus aureus
4.
Semin Thorac Cardiovasc Surg ; 31(4): 674-678, 2019.
Article in English | MEDLINE | ID: mdl-31271851
5.
Cardiovasc Revasc Med ; 20(12): 1140-1145, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30833209

ABSTRACT

BACKGROUND: The Magmaris bioresorbable magnesium scaffold was successfully tested in in-vitro and in clinical premarket studies. Subsequently the Magmaris postmarket program aimed to review intraprocedural data of at least 2000 patients to assess user preferences, guideline adherence and intraprocedural performance in clinical routine. METHODS: This international multicentre survey encompasses data from 356 hospitals across 45 countries. As part of the certification for Magmaris implantation, each hospital had to complete consecutive post-market evaluation forms of their first 10 commercial Magmaris patients. RESULTS: From June 2016 to May 2018, data on 2018 implantations were collected. Main reasons for selecting Magmaris was patients' life expectancy (67%, n = 1359) and low or not calcified lesions, (67%, n = 1357). Magmaris was successfully deployed in 99% of cases (n = 1995), predilatation was performed in 95% (n = 1922) and post-dilatation in 87% (n = 1756). Physicians rated the overall performance and the pushability as good or very good in 96% of cases (n = 1799). Guide wire friction, trackability, and conformability were rated as good or very good in 94% of cases, and crossability in 93%. The majority of patients were scheduled to receive dual antiplatelet therapy for up to 12 months. CONCLUSION: Generally, implantation guidelines were adhered to and theoretical advantages of the metal scaffold observed in in-vitro tests have translated into practice with good intraprocedural performance outcomes, confirming the controlled roll-out of this novel technology into clinical practice. SUMMARY FOR ANNOTATED TABLE OF CONTENT: The Magmaris 2000 program includes the first commercial cases at each hospital. Overall, data on 2018 implantations were collected. The high rate of pre- and post-dilatation as well as other parameters confirm that generally the implantation guidelines are adhered to and the good intraprocedural performance (rated as good or very good in 96%) confirm the theoretical advantages of a metallic scaffold in practice.


Subject(s)
Absorbable Implants/standards , Angioplasty, Balloon, Coronary/instrumentation , Angioplasty, Balloon, Coronary/standards , Cardiovascular Agents/administration & dosage , Coated Materials, Biocompatible/standards , Coronary Artery Disease/therapy , Guideline Adherence/standards , Magnesium , Practice Guidelines as Topic/standards , Practice Patterns, Physicians'/standards , Sirolimus/administration & dosage , Angioplasty, Balloon, Coronary/adverse effects , Cardiovascular Agents/adverse effects , Coronary Artery Disease/diagnostic imaging , Humans , Life Expectancy , Platelet Aggregation Inhibitors/administration & dosage , Product Surveillance, Postmarketing , Prosthesis Design/standards , Sirolimus/adverse effects , Time Factors , Treatment Outcome
6.
Medicine (Baltimore) ; 98(13): e14840, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30921183

ABSTRACT

Atherosclerotic diseases may include femoropopliteal artery stenosis or occlusion. Percutaneous transluminal angioplasty (PTA) is an effective and minimally invasive treatment strategy for atherosclerotic femoropopliteal artery stenosis/occlusion disease. Balloon angioplasty is a widely used technique in the management of occlusive disease in almost all arterial segments.We enrolled 111 diabetics with long femoropopliteal lesions, among which 54 received PTA with paclitaxel-coated balloon (the Paclitaxel group), and 57 with standard balloon catheters (the Control group).The primary outcome was set as angiographic late lumen loss (LLL) within 6 months; the secondary angiographic outcome was binary restenosis. Clinical outcomes included Rutherford clarification, ankle-brachial index (ABI) and rate of clinically driven target lesion revascularization (TLR). Two groups had similar basal clinical features, angiographic and procedural characteristics. Compared to controls, the Paclitaxel group had a significantly lower 6-month LLL rate, 12-month binary restenosis rate, 12-month TLR, lower Rutherford grades at 3 and 6 months, and higher ABI at 3 months. For all factors which might influence outcomes, fasting blood glucose was negatively correlated with ABI; the blood urea nitrogen (BUN) was positively related with the Rutherford clarification grades. In addition, the coronary heart disease (CHD) and smoking histories were positively correlated with residual stenosis after treatment.Collectively, the paclitaxel-coated balloon angioplasty can yield more favorable angiographic and clinical outcomes than standard uncoated balloon angioplasty, even in the more challenging lesions (the long and occlusive femoropopliteal lesions) in diabetics, when it had a similar safety profile to the traditional balloon. Blood glucose, BUN, CHD, and smoking imply poor curative effects.


Subject(s)
Angioplasty, Balloon/methods , Angioplasty/methods , Coated Materials, Biocompatible/therapeutic use , Diabetes Mellitus/epidemiology , Femoral Artery/pathology , Popliteal Artery/pathology , Aged , Angiography/methods , Angioplasty/adverse effects , Angioplasty, Balloon/adverse effects , Angioplasty, Balloon/statistics & numerical data , Antineoplastic Agents, Phytogenic/therapeutic use , Arterial Occlusive Diseases/pathology , Arterial Occlusive Diseases/therapy , Atherosclerosis/complications , Coated Materials, Biocompatible/adverse effects , Coated Materials, Biocompatible/standards , Diabetes Complications , Female , Femoral Artery/diagnostic imaging , Humans , Male , Middle Aged , Paclitaxel/administration & dosage , Paclitaxel/therapeutic use , Peripheral Arterial Disease/pathology , Peripheral Arterial Disease/therapy , Popliteal Artery/diagnostic imaging , Treatment Outcome
7.
EuroIntervention ; 13(13): 1574-1586, 2018 01 20.
Article in English | MEDLINE | ID: mdl-28948934

ABSTRACT

A previous Task Force of the European Society of Cardiology (ESC) and European Association of Percutaneous Cardiovascular Interventions (EAPCI) provided a report on recommendations for the non-clinical and clinical evaluation of coronary stents. Following dialogue with the European Commission, the Task Force was asked to prepare an additional report on the class of devices known as bioresorbable scaffolds (BRS). Five BRS have CE-mark approval for use in Europe. Only one device -the Absorb bioresorbable vascular scaffold- has published randomized clinical trial data and this data show inferior outcomes to conventional drug-eluting stents (DES) at 2-3 years. For this reason, at present BRS should not be preferred to conventional DES in clinical practice. The Task Force recommends that new BRS devices should undergo systematic non-clinical testing according to standardized criteria prior to evaluation in clinical studies. A clinical evaluation plan should include data from a medium sized, randomized trial against DES powered for a surrogate end point of clinical efficacy. Manufacturers of successful devices receive CE- mark approval for use and must have an approved plan for a large-scale randomized clinical trial with planned long-term follow-up.


Subject(s)
Absorbable Implants , Cardiovascular Agents/administration & dosage , Coated Materials, Biocompatible , Coronary Artery Disease/surgery , Percutaneous Coronary Intervention/instrumentation , Absorbable Implants/standards , Cardiovascular Agents/adverse effects , Clinical Decision-Making , Coated Materials, Biocompatible/standards , Consensus , Coronary Angiography , Coronary Artery Disease/diagnostic imaging , Humans , Percutaneous Coronary Intervention/adverse effects , Percutaneous Coronary Intervention/standards , Platelet Aggregation Inhibitors/administration & dosage , Prosthesis Design , Risk Factors , Time Factors , Treatment Outcome
8.
Int J Cardiol ; 252: 57-62, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29203209

ABSTRACT

BACKGROUND: Angioplasty with paclitaxel-coated balloons (PCB) is recommended for treatment of patients with coronary in-stent restenosis (ISR) according to European clinical practice guidelines. Most clinical trials have investigated iopromide-based PCB and there is a paucity of data comparing efficacy against butyryl-tri-hexyl citrate (BTHC)-based PCB. Our aim was to compare the performance of two widely-used PCB in the treatment of coronary ISR. METHODS: We analysed patients treated with BTHC- or iopromide-PCB for treatment of drug-eluting stent ISR in the setting of 2 consecutive trials with identical inclusion and exclusion criteria. The primary endpoint was diameter stenosis at 6-8month angiographic surveillance. The secondary endpoint of interest was the composite of death, myocardial infarction (MI) or target-lesion revascularisation (TLR) at 1year. Multivariate analysis was performed to adjust for differences in baseline characteristics between groups. RESULTS: In total, 264 patients were treated with BTHC-PCB (n=127) or iopromide-PCB (n=137). Baseline patient characteristics were similar for both groups. Post-procedure stenosis was slightly larger with BTHC-PCB (22.3 [SD 8.2]% vs. 18.4 [SD 9.9]%, P=0.001). At 6-8month angiography, diameter stenosis was 40.4 [SD 21.9]% vs. 37.4 [SD 21.4]% in the BTHC-PCB and iopromide-PCB groups, respectively (P=0.16, Padjusted=0.32). At 1year, death, MI or TLR occurred in 29 (23.2%) vs. 32 (23.4%) patients in the BTHC-PCB and iopromide-PCB groups, respectively (HR 1.03 [95% CI 0.62-1.70], P=0.91, Padjusted=0.96). CONCLUSIONS: In patients undergoing intervention for ISR, angioplasty with BTHC-PCB showed similar angiographic and clinical results at 1year compared with iopromide-PCB.


Subject(s)
Angioplasty, Balloon, Coronary/methods , Coated Materials, Biocompatible/administration & dosage , Coronary Angiography/methods , Coronary Restenosis/diagnostic imaging , Coronary Restenosis/therapy , Drug-Eluting Stents/adverse effects , Aged , Angioplasty, Balloon, Coronary/standards , Coated Materials, Biocompatible/standards , Coronary Angiography/standards , Drug-Eluting Stents/standards , Female , Follow-Up Studies , Humans , Middle Aged , Prosthesis Design/standards , Treatment Outcome
9.
Circ J ; 82(2): 477-485, 2018 01 25.
Article in English | MEDLINE | ID: mdl-28717068

ABSTRACT

BACKGROUND: A novel bare metal stent with an SiO2coating was developed to prevent excessive neointimal hyperplasia by inertization of the metallic stent surface. The efficacy of the device was demonstrated in a preclinical model. The aim of this first-in-man trial was to assess the safety and feasibility of the new device.Methods and Results:This prospective non-randomized single-arm trial was designed to enroll 35 patients with a de novo coronary lesion. Quantitative coronary angiography and optical coherence tomography (OCT) were performed at the baseline procedure and at the 6-month follow-up. Stent implantation was performed with OCT guidance according to optimal stent implantation criteria. The trial was terminated upon the advice of the data safety monitoring board after enrolling 14 patients due to the high incidence of re-intervention. Optimal OCT implantation criteria were achieved in only 8.3% of lesions. At 6 months, angiographic in-stent late lumen loss as the primary endpoint was 0.77±0.44 mm, and binary restenosis occurred in 33.3% of lesions. At the 6-month OCT, neointimal volume obstruction was 32.8±15.6% with a neointimal thickness of 237±117 µm. At 12 months, the device-oriented composite endpoint (defined as cardiac death, target vessel myocardial infarction, and clinically indicated target lesion revascularization rate) was 33.3%. CONCLUSIONS: In contrast with the preclinical study, the Axetis stent did not efficiently suppress neointimal hyperplasia in humans in this trial.


Subject(s)
Coated Materials, Biocompatible/chemistry , Coronary Stenosis/therapy , Silicon Dioxide , Stents/standards , Aged , Coated Materials, Biocompatible/standards , Coronary Restenosis/pathology , Humans , Hyperplasia/prevention & control , Middle Aged , Neointima/pathology , Stents/adverse effects , Treatment Failure
10.
J Neural Eng ; 14(4): 046011, 2017 08.
Article in English | MEDLINE | ID: mdl-28351998

ABSTRACT

OBJECTIVE: Performance of many dielectric coatings for neural electrodes degrades over time, contributing to loss of neural signals and evoked percepts. Studies using planar test substrates have found that a novel bilayer coating of atomic-layer deposited (ALD) Al2O3 and parylene C is a promising candidate for neural electrode applications, exhibiting superior stability to parylene C alone. However, initial results from bilayer encapsulation testing on non-planar devices have been less positive. Our aim was to evaluate ALD Al2O3-parylene C coatings using novel test paradigms, to rigorously evaluate dielectric coatings for neural electrode applications by incorporating neural electrode topography into test structure design. APPROACH: Five test devices incorporated three distinct topographical features common to neural electrodes, derived from the utah electrode array (UEA). Devices with bilayer (52 nm Al2O3 + 6 µm parylene C) were evaluated against parylene C controls (N ⩾ 6 per device type). Devices were aged in phosphate buffered saline at 67 °C for up to 311 d, and monitored through: (1) leakage current to evaluate encapsulation lifetimes (>1 nA during 5VDC bias indicated failure), and (2) wideband (1-105 Hz) impedance. MAIN RESULTS: Mean-times-to-failure (MTTFs) ranged from 12 to 506 d for bilayer-coated devices, versus 10 to >2310 d for controls. Statistical testing (log-rank test, α = 0.05) of failure rates gave mixed results but favored the control condition. After failure, impedance loss for bilayer devices continued for months and manifested across the entire spectrum, whereas the effect was self-limiting after several days, and restricted to frequencies <100 Hz for controls. These results correlated well with observations of UEAs encapsulated with bilayer and control films. SIGNIFICANCE: We observed encapsulation failure modes and behaviors comparable to neural electrode performance which were undetected in studies with planar test devices. We found the impact of parylene C defects to be exacerbated by ALD Al2O3, and conclude that inferior bilayer performance arises from degradation of ALD Al2O3 when directly exposed to saline. This is an important consideration, given that neural electrodes with bilayer coatings are expected to have ALD Al2O3 exposed at dielectric boundaries that delineate electrode sites. Process improvements and use of different inorganic coatings to decrease dissolution in physiological fluids may improve performance. Testing frameworks which take neural electrode complexities into account will be well suited to reliably evaluate such encapsulation schemes.


Subject(s)
Aluminum Oxide/standards , Coated Materials, Biocompatible/standards , Electrodes, Implanted/standards , Equipment Design/standards , Equipment Failure Analysis/methods , Polymers/standards , Xylenes/standards , Equipment Design/instrumentation , Microelectrodes/standards , Microelectrodes/trends , Time Factors
12.
Chem Asian J ; 12(8): 846-852, 2017 Apr 18.
Article in English | MEDLINE | ID: mdl-28218479

ABSTRACT

Herein we demonstrate a systematic investigation of chemically functionalizable, non-biofouling agarose films over large-area glass surfaces. Agarose films, prepared with various concentrations of aqueous agarose, were activated by using periodate oxidation to generate aldehyde groups at the termini of the agarose chains. The non-biofouling efficacy and binding capabilities of the activated films were evaluated by using protein and cellular patterning, performed by using a microarrayer, microcontact printing, and micromolding in capillaries. Characterization by using a fluorescence slide scanner and a scanning-probe microscope revealed that the pore sizes of the agarose films played an important role in achieving desirable film performance; the 0.2 wt % agarose film exhibited the optimum efficacy in this work.


Subject(s)
Coated Materials, Biocompatible/chemistry , Glass/chemistry , Proteins/chemistry , Sepharose/chemistry , Biofouling , Coated Materials, Biocompatible/standards , Fluorescence , Particle Size , Porosity , Surface Properties
13.
J Neurointerv Surg ; 9(9): 875-879, 2017 Sep.
Article in English | MEDLINE | ID: mdl-27474753

ABSTRACT

OBJECTIVE: The only pharmacologic prophylaxis for cerebral vasospasm after subarachnoid hemorrhage is oral nimodipine. A novel way to mitigate this risk may be to design a drug eluting stent that elutes verapamil over the time period typically associated with vasospasm. In this study, we explore different methods of coating nitinol stents with a bioabsorbable polymer and determine the release profile of various verapamil coated stents for the potential treatment of vasospasm. METHODS: Nitinol stents were coated with different concentrations of poly(lactic acid-co-glycolic acid) (PLGA) in chloroform solution and using three coating techniques: dip coating, spin coating, and electrospinning. Morphology of the coatings were studied with scanning electron microscopy. 12 verapamil eluting stents were then prepared using different verapamil concentrations and coatings with different numbers of layers. Drug release behaviors were studied using UV spectroscopy for 21 days. RESULTS: Electrospinning at 20% w/v resulted in a smooth uniform coating without significant surface irregularities, and may be the most effective technique to coat stents. Stents with a single layer of PLGA/verapamil coating showed a two phase release profile (initial burst release followed by a slow rate of release) whereas stents with a bilayer coating showed a lower level of initial release followed by a slower sustained release phase. CONCLUSIONS: Development of verapamil eluting stents that elute drug over the time course typical of cerebral vasospasm, and for either immediate or prophylactic treatment, is technically feasible. Further in vitro and in vivo studies are required to determine whether this can improve the outcome of patients after subarachnoid hemorrhage.


Subject(s)
Coated Materials, Biocompatible/administration & dosage , Coated Materials, Biocompatible/standards , Drug-Eluting Stents/standards , Subarachnoid Hemorrhage/surgery , Vasospasm, Intracranial/surgery , Verapamil/administration & dosage , Drug-Eluting Stents/trends , Humans , Microscopy, Electron, Scanning/methods , Subarachnoid Hemorrhage/complications , Treatment Outcome , Vasospasm, Intracranial/etiology
14.
Blood Purif ; 43(1-3): 101-122, 2017.
Article in English | MEDLINE | ID: mdl-27960188

ABSTRACT

INTRODUCTION: Accruing evidence suggests that vitamin E-coated membranes (ViE-m) might improve the clinical management of chronic hemodialysis (HD) patients. METHODS: We conducted a systematic review and meta-analysis of RCTs comparing ViE-m to conventional HD. Endpoints of interest were a series of biomarkers pertaining to anemia status, inflammation, oxidative stress and dialysis efficacy/status. RESULTS: Sixty studies were included. ViE-m significantly improved the Erythropoietin Resistance Index but had no impact on other anemia parameters. As for oxidative stress and inflammation, ViE-m produced a significant decrease in interleukin-6 levels, thiobarbituric acid reactive substances, plasma and red blood cell (RBC) malonylaldehyde and a significant increase in blood and RBC vitamin E. Conversely, ViE-m use had no impact on lipid profile, dialysis adequacy, blood pressure, albumin and uric acid. CONCLUSIONS: ViE-m might ameliorate anemia management by reducing oxidative stress and inflammation. Benefits of these bio-membranes on harder clinical outcomes are uncertain and need to be investigated by future, targeted trials.


Subject(s)
Coated Materials, Biocompatible/standards , Membranes, Artificial , Renal Dialysis/instrumentation , Vitamin E/pharmacology , Anemia/prevention & control , Humans , Inflammation/prevention & control , Kidney Failure, Chronic/therapy , Oxidative Stress/drug effects , Renal Dialysis/adverse effects
15.
J Cardiovasc Surg (Torino) ; 57(6): 806-810, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27647337

ABSTRACT

Endovascular techniques have improved markedly over the past several decades. Plain old balloon angioplasty can only reach patencies around 40% after 1 year. Scaffolding stents have resulted in improved short-term results but encountered limitations for longer-term durability. With the introduction of drug-eluting technologies the process of intimal hyperplasia might be slowed, resulting in improved long-term patency results. At first, limus-eluting technologies were not able to transfer the enthusiasm from the coronaries to the infrainguinal vascular bed. However, the newer generation paclitaxel-eluting technologies perform significantly better in femoropopliteal arteries than their non-eluting or non-coated counterparts. The results of a prospective randomized trial comparing DES versus DCB is eagerly awaited. For the moment there seems, based on the meta-analysis, no difference between the two treatment modalities. Although, we need to keep in mind that DCB perform worse in long calcified lesions.


Subject(s)
Cardiovascular Agents/administration & dosage , Coated Materials, Biocompatible/standards , Drug-Eluting Stents/standards , Endovascular Procedures/instrumentation , Endovascular Procedures/standards , Femoral Artery , Peripheral Arterial Disease/therapy , Standard of Care , Constriction, Pathologic , Endovascular Procedures/adverse effects , Femoral Artery/diagnostic imaging , Femoral Artery/physiopathology , Humans , Peripheral Arterial Disease/diagnostic imaging , Peripheral Arterial Disease/physiopathology , Prosthesis Design , Risk Factors , Treatment Outcome , Vascular Access Devices/standards , Vascular Patency
16.
Contrast Media Mol Imaging ; 11(5): 340-349, 2016 09.
Article in English | MEDLINE | ID: mdl-27307214

ABSTRACT

The purpose of this work is evaluating the effect of ultra small superparamagnetic iron oxide nanoparticles (USPIONs) coatings on encapsulation efficiency in liposomes and cellular cytotoxicity assay. Moreover, we assessed the effects of surface engineering on the relaxivity of magnetoliposome nanoparticles in order to create a targeted reagent for the intelligent diagnosis of cancers by MRI. For estimating the effect of nanoparticle coatings on encapsulation, several kinds of USPIONs coated by dextran, PEG5000 and citrate were used. All kinds of samples are monodispersed and below 100 ± 10 nm and the coatings of USPIONs have no significant effect on magnetoliposome diameter. The coating of USPIONs could have effect on percentage of encapsulation. The dextran coated USPIONs have more stability and quality accordingly the encapsulation increased up to 92%, then the magnetoliposome nano particles have been targeted by Herceptin and anti-HER2 VHH, separately. Over storage period of four weeks the resulting particles were stable and physico-chemical properties such as size and zetapotential did not show any significant changes. The relaxivity of contrast agents was measured using a 1.5 T MRI. The r2/r1 ratio was more than two for all samples which demonstrate the negative contrast enhancing of all SPION embedded specimens. The high ratio of r2/r1 as well as high r2 is the best combination of a negative contrast agent as it is obtained for pure magnetite. The value of r2/r1 for all other samples including Herceptin targeted magnetoliposome, anti-HER2 VHH targeted magnetoliposome and non-targeted magnetoliposome were between ~21 to ~28, which show the magnetite embedded samples have enough negative contrast to be detectable by MRI. Therefore the HER2 targeted magnetoliposomes are a good and stable candidate as contrast agents in clinical radiology and biomedical research with minimal cytotoxicity and biocompatibility effects. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Coated Materials, Biocompatible/pharmacology , Liposomes/chemistry , Magnetic Resonance Imaging/methods , Magnetite Nanoparticles , Neoplasms/diagnostic imaging , Citric Acid , Coated Materials, Biocompatible/standards , Contrast Media , Dextrans , Ferrosoferric Oxide , Humans , Magnetite Nanoparticles/chemistry , Polyethylene Glycols , Receptor, ErbB-2/immunology , Single-Domain Antibodies/immunology
17.
World Neurosurg ; 91: 163-71, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27060512

ABSTRACT

OBJECTIVE: Many studies have addressed the problem of loosening pedicle screws in spinal surgery, which is a serious concern. Titanium coating of medical implants (arthroplasty) is common, but few studies involving in vivo spine models have been reported. We evaluated the radiological, mechanical, and histological characteristics of titanium-coated pedicle screws compared with uncoated or hydroxyapatite-coated pedicle screws. METHODS: Three different types of pedicle screws, i.e., uncoated, hydroxyapatite-coated, and titanium-coated, were implanted into the lumbar 3-4-5 levels of 9 mature miniature pigs. Radiological evaluation of loosening of pedicle screws was performed. Peak torsional extraction torque was tested in the 42 screws from 7 miniature pigs at 12 weeks postoperatively. The implant-bone interface of the remaining 12 pedicle screws from 2 miniature pigs in each group was assessed by micro-computed tomography and histologic studies. RESULTS: The incidence of loosening at 12 weeks postoperatively was not significantly different between the titanium-coated pedicle screw group and the other groups. The titanium-coated pedicle screw group exhibited the greatest mean extraction torsional peak torque at 12 weeks postoperatively (P < 0.05). Quantitative micro-computed tomography data were greatest in the titanium-coated pedicle screw group (P < 0.05). Histologic findings showed osteointegration with densely packed new bone formation at the screw coating-bone interface in the titanium-coated pedicle screw group. CONCLUSIONS: Fixation strength was greatest in the titanium-coated pedicle screw group. Osteointegration at the interface between the titanium-coated implant and bone produced prominent and firm bonding. The titanium-coated pedicle screw is a promising device for application in spinal surgery.


Subject(s)
Coated Materials, Biocompatible/standards , Durapatite , Lumbar Vertebrae/surgery , Orthopedic Procedures/standards , Pedicle Screws/standards , Titanium , Animals , Arthroplasty , Disease Models, Animal , Female , Swine
18.
Cardiol J ; 21(5): 557-68, 2014.
Article in English | MEDLINE | ID: mdl-24526505

ABSTRACT

BACKGROUND: Whether drug-eluting stents with biodegradable polymers (BP-DES) improve safety, especially with respect to stent thrombosis (ST) compared with permanent polymers DES (PP-DES), remains uncertain. We aimed to compare the short- and long-term outcomes and the ST risk in patients treated with BP-DES vs. PP-DES METHODS: We searched Medline, Embase, Web of science, CENTRAL databases, and conferenceproceedings/abstracts for randomized controlled trials (RCTs) comparing BP-DES with PP-DES. The primary endpoint was to compare the risks of overall and different temporalc ategories of definite/probable ST. Other clinical outcomes were target lesion revascularization (TLR), myocardial infarction (MI), and all-cause death in short-term (≤ 1 year) and long-term follow-up. The meta-analyses were performed by computing odds ratios (ORs) with 95% confidence intervals (CIs) using a random-effects model. RESULTS: Nineteen RCTs including 20,229 patients were analyzed. Overall, BP-DES significantly decreased the risks of very late definite/probable ST (OR 0.33; 95% CI 0.16-0.70), and TLR in long-term follow-up (OR 0.70; 95% CI 0.52-0.95) compared with PP-DES. There were no significant differences between the groups regarding MI incidence and mortality during both short and long follow-up periods. In stratified analyses, the long-term superiority of BP-DES was maintained only by using first-generation DES as the comparators. CONCLUSIONS: The present meta-analysis indicated that BP-DES were more efficacious than PP-DES at reducing the risks of very late ST and long-term TLR, but it could vary by heterogeneities in the use of PP-DES comparators. Additional rigorous RCTs with longer follow-up periods are warranted to verify these very promising long-term endpoints.


Subject(s)
Coated Materials, Biocompatible/standards , Coronary Restenosis/prevention & control , Drug-Eluting Stents/standards , Guideline Adherence , Myocardial Infarction/surgery , Randomized Controlled Trials as Topic/methods , Humans
19.
Catheter Cardiovasc Interv ; 83(3): 427-35, 2014 Feb 15.
Article in English | MEDLINE | ID: mdl-23934956

ABSTRACT

Drug-coated balloons are a new tool for the treatment of patients with coronary artery disease. The main feature of this technology is a rapid and homogenous transfer of an antiproliferative drug (paclitaxel) to the vessel wall just at the time of balloon inflation, when neointimal proliferation, in response to angioplasty, is the highest. Moreover, drug-coated balloons share adjuntive advantages over stents: the absence of permanent scaffold and polymer, the respect of the original coronary anatomy, and limited inflammatory stimuli, thereby allowing for short-term dual antiplatelet therapy. To this day, a lot of devices are available in the market, with limited scientific data for the vast majority of them. Thus, the Italian scientific society of interventional cardiologists GISE decided to coordinate the efforts of a group of reknown experts on the field, in order to obtain a Position Paper on the correct use of drug-coated balloons in all the settings of coronary artery disease, giving a class of indication to each one, based on the clinical evidence. This Position Paper represents a quick reference for operators, investigators, and manufactures to promote the understanding and the correct use of the drug-coated balloon technology in everyday clinical practice.


Subject(s)
Angioplasty, Balloon, Coronary/instrumentation , Angioplasty, Balloon, Coronary/standards , Cardiac Catheters/standards , Cardiology/standards , Cardiovascular Agents/administration & dosage , Coated Materials, Biocompatible/standards , Coronary Artery Disease/therapy , Myocardial Infarction/therapy , Angioplasty, Balloon, Coronary/adverse effects , Coronary Artery Disease/diagnosis , Coronary Restenosis/etiology , Coronary Restenosis/prevention & control , Drug Administration Schedule , Drug Therapy, Combination , Equipment Design , Humans , Myocardial Infarction/diagnosis , Neointima , Platelet Aggregation Inhibitors/administration & dosage , Treatment Outcome
20.
Heart Vessels ; 27(4): 360-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-21725668

ABSTRACT

The National Institute for Clinical Excellence (NICE) guidelines recommend the use of bare-metal stents (BMS) in non-complex lesions with a low risk of restenosis (diameter ≥3 mm and lesion length ≤15 mm) and the use of drug-eluting stents (DES) in more complex lesions with a high risk of restenosis (diameter <3.0 mm or lesion length >15 mm). However, the guidelines were created based on studies evaluating BMS and DES only. We performed an analysis of patients undergoing non-urgent percutaneous coronary intervention with the novel endothelial cell capturing stent (ECS). The ECS is coated with CD34(+) antibodies that attract circulating endothelial progenitor cells to the stent surface, thereby accelerating the endothelialization of the stented area. We analyzed all patients enrolled in the worldwide e-HEALING registry that met the NICE criteria for either low-risk or high-risk lesions and were treated with ≥1 ECS. The main study outcome was target vessel failure (TVF) at 12-month follow-up, defined as the composite of cardiac death or MI and target vessel revascularization (TVR). A total of 4,241 patients were assessed in the current analysis. At 12-month follow-up, TVF occurred in 7.0% of the patients with low-risk lesions and in 8.8% of the patients with high-risk lesions (p = 0.045). When evaluating the diabetic patients versus the non-diabetic patients per risk group, no significant differences were found in TVF, MI or TVR in either risk group. The ECS shows good clinical outcomes in lesions carrying either a high or a low risk of restenosis according to the NICE guidelines with comparable rates of cardiac death, myocardial infarction, and stent thrombosis. The TVF rate with ECS was slightly higher in patients with high-risk lesions, driven by higher clinically driven TLR. The risk of restenosis with ECS in patients carrying high-risk lesions needs to be carefully considered relative to other risks associated with DES. Furthermore, the presence of diabetes mellitus did not influence the incidence of TVF in either risk group.


Subject(s)
Angioplasty, Balloon, Coronary/instrumentation , Angioplasty, Balloon, Coronary/standards , Coronary Restenosis/prevention & control , Coronary Stenosis/therapy , Coronary Vessels/pathology , Endothelial Cells/pathology , Government Agencies/standards , Stem Cells/pathology , Stents/standards , Aged , Angioplasty, Balloon, Coronary/adverse effects , Angioplasty, Balloon, Coronary/mortality , Antibodies/administration & dosage , Antigens, CD34/immunology , Coated Materials, Biocompatible/standards , Coronary Restenosis/etiology , Coronary Restenosis/mortality , Coronary Restenosis/pathology , Coronary Stenosis/mortality , Coronary Stenosis/pathology , Coronary Vessels/immunology , Endothelial Cells/immunology , Female , Guideline Adherence/standards , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Myocardial Infarction/etiology , Neointima , Patient Selection , Practice Guidelines as Topic/standards , Product Surveillance, Postmarketing , Proportional Hazards Models , Prosthesis Design , Registries , Retrospective Studies , Risk Assessment , Risk Factors , Stem Cells/immunology , Thrombosis/etiology , Time Factors , Treatment Outcome
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