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The comparison of bioabsorbable-polymer and durable-polymer stents has continued to be debated, and there is ongoing concern regarding vascular healing and late stent thrombosis. This study compared the vascular healing at 8-month follow-up by optical coherence tomography (OCT) between 4 different kinds of new generation drug-eluting stents (DESs). We enrolled 112 patients (112 de novo lesions) who underwent OCT guided percutaneous coronary intervention with 4 kinds of new generation DESs including bioabsorbable-polymer everolimus-eluting stents (BP-EESs), bioabsorbable-polymer sirolimus-eluting stents (BP-SESs), durable-polymer everolimus-eluting stents (DP-EESs), and durable-polymer zotarolimus-eluting stents (DP-ZESs) and an 8-month follow-up angiogram and OCT were performed between July 2016 and April 2018. We divided them into two groups, namely BP and DP groups. We compared the OCT parameters including the percentage of uncovered struts, malapposed struts and the mean neointimal hyperplasia (NIH) thickness between the two groups. BP group consisted of 51 lesions (BP-EESs were used in 27, BP-SESs in 24 lesions) and DP group consisted of 61 lesions (DP-EESs were used in 35 and DP-ZESs in 26 lesions). The percentage of uncovered struts and malapposed struts were significantly lower (7.2 ± 8.9 vs. 15.0 ± 17.1%, p = 0.01, 0.9 ± 1.7 vs. 2.7 ± 5.2%, p = 0.03) and the mean NIH thickness was significantly thicker in BP group than DP group (112 ± 54 vs. 83 ± 31 µm, p

Introduction The findings of many new cardiology clinical trials over the last year have been published or presented at major international meetings. This paper aims to describe and place in context a summary of the key clinical trials in cardiology presented between January and December 2016. Methods The authors reviewed clinical trials presented at major cardiology conferences during 2016 including the American College of Cardiology (ACC), European Association for Percutaneous Cardiovascular Interventions (EuroPCR), European Society of Cardiology (ESC), European Association for the Study of Diabetes (EASD), Transcatheter Cardiovascular Therapeutics (TCT), and the American Heart Association (AHA). Selection criteria were trials with a broad relevance to the cardiology community and those with potential to change current practice. Results A total of 57 key cardiology clinical trials were identified for inclusion. Here we describe and place in clinical context the key findings of new data relating to interventional and structural cardiology including delayed stenting following primary angioplasty, contrast-induced nephropathy, management of jailed wires, optimal duration of dual antiplatelet therapy (DAPT), stenting vs bypass for left main disease, new generation stents (BioFreedom, Orsiro, Absorb), transcatheter aortic valve implantation (Edwards Sapien XT, transcatheter embolic protection), and closure devices (Watchman, Amplatzer). New preventative cardiology data include trials of bariatric surgery, empagliflozin, liraglutide, semaglutide, PCSK9 inhibitors (evolocumab and alirocumab), and inclisiran. Antiplatelet therapy trials include platelet function monitoring and ticagrelor vs clopidogrel for peripheral vascular disease. New data are also presented in fields of heart failure (sacubitril/valsartan, aliskiren, spironolactone), atrial fibrillation (rivaroxaban in patients undergoing coronary intervention, edoxaban in DC cardioversion), cardiac devices (implantable cardioverter defibrillator in non-ischemic cardiomyopathy), and electrophysiology (cryoballoon vs radiofrequency ablation). Conclusion This paper presents a summary of key clinical cardiology trials during the past year and should be of practical value to both clinicians and cardiology researchers.

Introduction Multiple significant, potentially practice changing clinical trials in cardiology have been conducted and subsequently presented throughout the past year. Methods In this paper, the authors have reviewed and contextualized significant cardiovascular clinical trials presented at major international conferences of 2015 including American College of Cardiology, European Association for Percutaneous Cardiovascular Interventions, American Diabetes Association, European Society of Cardiology, Transcatheter Cardiovascular Therapeutics, Heart Rhythm Congress, and the American Heart Association Scientific Sessions. Results The authors describe new trial data for heart failure (including eplerenone, finerenone, patiromer, sacubitril/valsartan, the beta 3 agonist mirabegron, sitagliptin, empagliflozin, alginate-hydrogel LV epicardial implant), anticoagulation (idarucizumab and andexanet alfa reversal agents, adherence programmes, practice in ablation), transcatheter aortic valve replacement (long-term data, valve-in-valve use, the TriGuard embolic deflecting device), patent foramen ovale closure, cardiovascular prevention (PCSK9 inhibitors, hypertension treatment) and antiplatelets strategies (extended duration therapy with clopidogrel or ticagrelor). Trial data are also described for contemporary technologies including the Biofreedom polymer-free drug coated stent, bioabsorbable stents, PCI strategies, left main treatment, atrial fibrillation ablation techniques, leadless pacemakers and the role of coronary computed tomographic angiography. Conclusions This paper summarizes and contextualizes multiple pertinent 2015 clinical trials and will be of interest to both clinicians and cardiology researchers.

With the widespread adoption of laparoscopic cholecystectomy and living-donor liver transplantation in recent years, complications involving the biliary system, stenosis in particular, are increasing. Various invasive and non-invasive techniques are now available for the treatment of biliary stenosis, but all are compromised by a high risk of recurrence and other problems. As a potential solution, our group has developed a bioabsorbable polymer (BAP) tube for implantation as a bypass graft. In the study reported here, we implanted this BAP tube and confirmed bile duct regeneration at the graft site after the tube had been degraded and absorbed into the body. We briefly describe our findings on extrahepatic biliary tissue regeneration, focusing on the possibility of its clinical application. This artificial bile duct may promote the development of novel treatments for biliary disease.

Cancer is a devastating disease, being responsible for 13 % of all deaths worldwide. One of the main challenges in treating cancer concerns the fact that anti-cancer drugs are not highly specific for the cancer cells and the "death" of healthy cells in the course of chemotherapy treatment is inevitable. In this sense, the use of drug delivery systems (DDS) can be seen as a powerful tool to minimize or overcome this very important issue. DDS can be designed to target specific tissues in order to mitigate side effects. Bioabsorbable polymers, due to their inherent characteristics, and because they can be synthesized in a variety of forms, are materials whose importance in the DDS for cancer therapy has risen significantly in the last years. This review intends to give an overview about the latest developments in the use of bioabsorbable polymers as DDS in cancer therapy, with special focus on nanoparticles, micelles, and implants.

Since the advent of percutaneous coronary intervention, enormous advances have been made in the treatment of coronary artery disease. Angioplasty and bare metal stents were plagued by high rates of restenosis leading to repeat revascularization procedures. Examination of the underlying pathophysiology of restenosis led to the development of drug-eluting stents to reduce neointimal hyperplasia. However, as restenosis rates declined, length of dual antiplatelet therapy use and risk of long-term stent thrombosis associated with drug-eluting stents increased. Subsequent generations have improved each facet of stent design. Novel alloys maintain durability and reduce strut thickness to increase deliverability, biocompatible polymers decrease the inflammatory response and improve drug elution kinetics, and new generations of drugs predictably inhibit restenosis. Developments on the horizon include stents with bioabsorbable polymers and platforms. The purpose of this review is to assess the evolution of stent design and the evidence behind each generation and to peer into the future of stent technology.

The cyclic six, seven, and eight-membered oligosaccharides α-, β-, and γ-cyclodextrins (CDs) can serve as hosts for a variety of polymer guests to form crystalline inclusion compounds (ICs), wherein the guest polymers are included in the continuous narrow channels (0.5-1.0 nm in diameter) formed by the host CD stacks. Polymers included as guests in CD-ICs are highly extended and segregated from neighboring chains by the walls of the host CD bracelets. As a consequence, when polymer-CD-ICs are treated with solvents for CDs that are non-solvents for the included polymers or with amylase enzymes, the CDs are removed and the guest polymers are coalesced into bulk samples whose structures, morphologies, and even chain conformations are different from those achieved by consolidation from their randomly coiling, entangled solutions and melts. Often these CD-IC coalesced and consequently reorganized polymer samples exhibit properties that are distinct from their normally processed bulk samples. Here we describe the CD-IC processing of several biodegradable/bioabsorbable homopolymers, copolymers, and blends made from poly (L-lactic acid), poly (e-caprolactone), and poly (β-hydroxybutyrate)s, with special emphasis placed on their improved and controllable properties. For example, the phase segregation and consequent crystallinities of their normally incompatible homopolymer blends and their block copolymers may be controlled and thus improved. In addition, co-inclusion of small molecule guests, such as drugs or anti-bacterials, in their common CD-ICs, and subsequent coalescence, yields well-mixed blends of these biodegradable/bioabsorbable polymers and the small molecule co-guests, which may lead, for example, to the improved delivery of drugs.

The Angio-Seal™ hemostatic puncture closure device is the culmination of development efforts dating from 1986. Devel-opment was driven to solve problems of delivering a multi-piece bioabsorbable puncture closure assembly through an introducer, the precise placement of the device in the vessel, the mastery of molding tiny absorbable polymer components, the manufacture of collagen hemostatic sponges having strong tear strength, and the testing of very large samples to establish safety and efficacy. Improvements included in the new 6F device to improve deployment reliability are also discussed.

In order to provide bioabsorbable self-reinforced poly (L/DL) lactide (P(L/DL)LA) 70 : 30 plates with osteoconductive bioactivity, spheres (125–250 µm) of a bioactive glass 13–93 were implanted onto a polymer plate preform by pressing. With appropriate pressing parameters glass spheres were firmly attached onto the polymer plate. The top of the glass spheres remained exposed. The bioactivity of the coated plates was examined in vitro with immersion in phosphate-buffered saline (PBS). Apatite was observed to precipitate on exposed glass sphere surfaces and the whole polymer surface within the first three days. © 1999 Kluwer Academic Publishers

The use of degradable implants in recent years has brought not only good results. Foreign body reactions to implantation of degradable polymers clearly curtailed the initial expectations. Bioabsorbable polymers have been used for sutures, vascular clips, and fixation implants for both intra-articular fractures and malleolar fractures. In the literature these implants are controversial. Potential benefits remain for the use of this material for interference screws if the problems of inflammation are minimal and the fixation properties are sufficient. There is no need for a second operation for removal. In one patient, 4.5 years after to implantation of an degradable interference screw (Copolymer 85/15 D,L lactide glycolide; Biologically Quiet, Instrument Makar, Inc. Mount Hope, MI 48864, USA) we took an biopsy and made histological examinations. No foreign body reaction or inflammation signs could be detected.

Synthetic dural substitutes composed of bioabsorbable polymers were used in 20 patients during neurosurgical operation. Clinical manifestations such as operative wound features, white blood cell counts, C-reactive protein, and computed tomography were evaluated after neurosurgical operations. Transient subcutaneous collection of cerebrospinal fluid was observed in three patients. No other significant complication was observed. This preliminary report indicates the effectveness of the bioabsorbable artifical dura mater without risking virally transmitted infection when compared with a cadaveric dura mater graft.

1. Antinicotine films based on bioabsorbable polymers are an efficacious and convenient therapy against tobacco smoking. 2. Antinicotine films containing anabasine (1.5 mg), cytisine (1.5 mg), or their mixture (0.75 mg+0.75 mg) have positive effect in 75.8% of patients with nicotinism, 46.8% of the patients giving up smoking completely. Films containing cytisine or mixture of cytisine and anabasine are most efficacious. 3. No side effects of antinicotine films requiring termination of treatment were found. No contraindications were found for patients with ischemic heart disease, arterial hypertension, or diabetes mellitus.

Non-reinforced and self-reinforced bioactive-bioabsorbable composite rods were produced by extrusion and solid state die-drawing using P(L/DL)LA matrix and spherical glass particles. The structure and mechanical properties of composites were measured before and after die-drawing. The structure examination of composites by SEM showed the formation of fibrous reinforced structure of the polymer with spindle-shaped pores around the glass spheres during and oriented in the direction of die-drawing. Incorporation of glass into the polymer matrix turns the composite more brittle compared to neat polymer. By die-drawing the brittleness of the composite can be eliminated.Not only the bioactivity and controlled degradation rate of composite but also structure and mechanical properties achieved during die-drawing make the self-reinforced bioactive glass- bioabsorbable polymer composites a novel implant material for temporary support of healing tissues.