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• Synthesized compounds and crystal structures are (C 5 H 7 N 4) 2 [SnCl 6 ] 2- (1) and (C 5 H 7 N 4) 2 [SnBr 6 ]2- (2). • The crystal was examined by UV, photoluminescence and surface morphology with EDS. • CSM shows ideal octahedral geometry for both crystal anions. • Biological activity indicates efficacy against the bacterial strains. The novel organic-inorganic hybrid materials (C 5 H 7 N 4) 2 [SnCl 6 ] 2- (1) and (C 5 H 7 N 4) 2 [SnBr 6 ]2- (2) have been synthesized and characterized by single-crystal X-ray diffraction at room temperature. Both compounds demonstrate the crystal system was triclinic with Pī space group. Hirshfeld surface analysis investigate the intermolecular interactions and crystal packing derived by single-crystal XRD data reveals the closer contacts associated with strong interactions. Infrared spectrum of both compounds shows the N H stretching band at 3396 cm−1 which indicates a protonated amine group. The product crystals optical characteristics were inspected using UV–visible and photoluminescence spectroscopy. The thermal characteristics were evaluated simultaneously using thermogravimetric (TG) and differential thermal analysis. Tin formal oxidation state was determined as +4 through bond valence sum calculations and CSM shows the ideal octahedral geometry of the anions. DFT calculations utilizing the B3LYP method with the LanL2DZ basis set provide optimized geometries and molecular electrostatic potential maps. We explored the energy difference between (HOMO) and (LUMO) orbitals to understand molecular electrical transport capabilities. The biological activity of the investigated compounds are examined against pathogens which indicates efficacy against bacterial strains. [Display omitted] [ABSTRACT FROM AUTHOR]

• Self-assembly of less toxic Tin(IV)–thiomorpholinium hybrids harvests at room temperature. • The BVS values for (C 4 H 10 NS) 2 SnCl 6.H 2 O and (C 4 H 10 NS) 2 SnBr 6 are 4.01 and 3.94, respectively, confirming the formal oxidation state of tin as a quadrivalent. • The effective coordination number values suggest that both compounds exhibit near-perfect octahedral geometry. • The energy gap for the bromo hybrid is 3.00 eV, while that of the chloro hybrid is 3.91 eV. • The intermolecular interactions present in compounds were elucidated through the analysis of 3D Hirshfeld surfaces and 2D fingerprint plots. At room temperature, organic-inorganic hybrids, including bis(thiomorpholinium) hexachlorostannate(IV) hydrate (1) and bis(thiomorpholinium) hexabromostannate(IV) (2), were synthesized from thiomorpholinium chloride/bromide. The hybrids underwent characterization using, IR, elemental, NMR, TGA, DRS and PL spectroscopy, along with single-crystal X-ray diffraction (SCXRD). SCXRD confirms compounds are crystallized in a monoclinic system exhibiting centrosymmetric space groups (C2/ c andP2 1 / c for (1) and (2)). The SCXRD structures of the hybrids unveiled significant H-bonded interactions between the thiomorpholinium cation and the SnCl 6 2-/SnBr 6 2- anions. At room temperature, optical absorption measurements revealed band gaps of 3.91 eV for (1) and 3.00 eV for (2).TGA confirmed the proposed formulas of the compounds.BVS calculations conducted on SnCl 6 2- and SnBr 6 2- anions yielded values of 4.01 and 3.94, respectively. Fingerprint plots were employed to identify and quantify the proportion of hydrogen bonding interactions. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Scaffold thromboses (ST) and adverse events and have been associated with bioresorbable vascular scaffolds (BVS) at long-term, but their mechanism remains unclear. We sought to evaluate patient and lesion characteristics associated with mid- to long-term outcomes in patients treated with BVS.Methods: This is an observational single-center, single-arm, retrospective study evaluating the performance of BVS in an all-comer population, including complex lesions (chronic total occlusions, long lesions), small vessels, and acute coronary syndromes (ACS).Results: From May 2013 to June 2015, we included 482 patients (580 lesions) that were treated with BVS implantation including 71.2% treated for ACS in the present analysis. Mean follow-up period was 816.2 ± 242.6 days. The primary endpoint was device oriented cardiac events (DOCE), defined as a composite of target-lesion revascularization (TLR), ST, target vessel myocardial infarction (TVMI) and cardiac death. Using Kaplan-Meier methods, the DOCE and ST rates at 36 months were 9.4% and 2.3%, respectively. No ST occurred between 2 and 3 years and ST occurred after 3 years, in one patient. Using multivariate analysis, ACS was the only significant predictor of lower rates of DOCE (p = 0.04, HR: 0.47, 95% CI: 0.23-0.96).Conclusions: In this large all-comers real-world cohort, lesions treated with BVS had non-negligible rates of DOCE and ST, in line with previous published randomized trials. The occurrence of very late event was very low after 24 months. ACS patients had lower rates of DOCE. [ABSTRACT FROM AUTHOR]

Background: Limited information is available on the use of Bioresorbable Vascular Scaffold (BVS) in bifurcations involving significant side branches. When treating bifurcation disease with metal stents, the recommendation is to choose a stent diameter based on the distal main vessel diameter. Whether this sizing strategy is applicable to BVS is currently unknown.Methods: We randomised 37 patients undergoing elective PCI for 'false' bifurcation disease (Medina 0,1,0; 1,0,0; 1,1,0) to receive BVS based either on proximal or distal reference diameters. Optical Frequency Domain Imaging (OFDI) measurements were performed pre BVS insertion to obtain proximal and distal reference diameters and post implantation. BVS size was chosen according to the proximal or distal reference diameter as per randomisation. Implantation was performed using the PSP technique tailored to bifurcation stenting. OFDI was repeated post implantation to confirm satisfactory expansion and apposition.Results: Baseline demographics between the two groups were similar. Patients were aged 62.8 ± 3.3 years; 76% were male. Mean side branch diameter was 2.24 ± 0.13 mm. TIMI III flow in the main vessel was achieved in all cases. Side branch occlusion occurred in 1 case (2.7%). In the distal-sizing arm, there was a greater incidence of significant malapposition (>300 μm) at the proximal end of the scaffold on OCT (2.3% versus 0.8%, p 0.023). The incidence of distal edge dissections was numerically greater in the proximal-sizing group but this was not statistically significant (31.3% vs 11.8%, p 0.17).Conclusion: Both proximal and distal sizing strategies have similar procedural complication rates when using the ABSORB BVS to treat coronary bifurcations. However a proximal sizing strategy is associated with less malapposition and may be preferable. [ABSTRACT FROM AUTHOR]

Randomised trials have demonstrated higher midterm rates of adverse events and device thrombosis with Absorb-BVS compared to contemporary drug-eluting-stents (DES). BVS failure was ascribed to the implantation technique and consequently two large randomised trials evaluated the clinical impact of an optimised scaffold-implant-procedure. However, pooling together data from ABSORB-IV and those of the COMPARE-ABSORB, the scaffold was still associated with a statistically significant increased risk of target-vessel myocardial-infarction (OR 1.5; 95% CI 1.04-2.17; P = 0.03) and thrombotic events (OR 2.85; 95% CI 1.33-6.11; P = 0.007) at 1-year. Such kind of results could be in part attributed to a lower radial force and the higher acute recoil of the BVS as observed in previous studies. Besides a painstaking implantation technique, future generations of bioresorbable stents should incorporate an excellent mechanical propriety in order to compete with the current-generation DES. [ABSTRACT FROM AUTHOR]

Background/purpose: Multiple BRSs and specifically the Absorb scaffold (BVS) (Abbott Vascular, Santa Clara, CA USA) have been often used to treat long diffuse coronary artery lesions. We evaluate by a computational fluid dynamic(CFD) study the impact on the intravascular fluid rheology on multiple bioabsorbable scaffolds (BRS) by standard overlapping versus edge-to-edge technique.Methods/materials: We simulated the treatment of a real long significant coronary lesion (>70% luminal narrowing) involving the left anterior descending artery (LAD) treated with a standard or edge-to-edge technique, respectively. Simulations were performed after BVS implantations in two different conditions: 1) Edge-to-edge technique, where the scaffolds are kissed but not overlapped resulting in a luminal encroachment of 0.015cm (150μm); 2) Standard overlapping, where the scaffolds are overlapped resulting in a luminal encroachment of 0.030cm (300μm). After positioning the BVS across the long lesion, the implantation procedure was performed in-silico following all the usual procedural steps.Results: Analysis of the wall shear stress (WSS) suggested that at the vessel wall level the WSS were lower in the overlapping zones overlapping compared to the edge-to-edge zone (∆=0.061Pa, p=0.01). At the struts level the difference between the two WSS was more striking (∆=1.065e-004 p=0.01) favouring the edge-to-edge zone.Conclusions: Our study suggested that at both vessel wall and scaffold struts levels, there was lowering WSS when multiple BVS were implanted with the standard overlapping technique compared to the "edge-to-edge" technique. This lower WSS might represent a substrate for restenosis, early and late BVS thrombosis, potentially explaining at least in part the recent evidences of devices poor performance. [ABSTRACT FROM AUTHOR]

Background Bioresorbable vascular scaffolds (BVS) are widely used in routine clinical practice. While previous studies reported acceptable short- to midterm outcome after BVS implantation, data on longer-term outcome are rare. Methods Patients treated with at least one Absorb®-BVS were consecutively enrolled. Follow-up data were assessed after 834.0 [769.0–1026.0] days. The primary device-oriented composite endpoint (DOCE) was defined as cardiovascular death, myocardial infarction (MI) and/or target lesion revascularization (TLR). Results Between 2012 and 2014, 195 patients were included into study analysis. Overall, 244 BVS were implanted. Mean patient age was 64.0[54.3–74.0] years. Three-quarter of patients had an ACS; of those 42.9% had ST-elevation-MI and 40.8% had non-ST-elevation-MI. DOCE occurred in 3.1%, 6.7%, 11.8% and 15.4% of patients during hospital stay, within 6-months, 18-months or during the complete follow-up period, respectively. In those patients, median time until DOCE was 211.5[43.25–567.25] days. In 11 (36.7%) patients DOCE occurred after > 12 months. Using univariable analysis, bifurcation stenting was associated with a hazard ratio (HR) of 11.8[2.38–58.57] for TLR ( p = 0.002) and 2.1[1.02–4.49] for DOCE ( p = 0.045). Similarly, in ACS patients, bifurcation stenting was associated with an increased risk for TLR (HR = 10.4[2.01–53.56]; p = 0.005) and for DOCE (HR = 2.4[1.09–5.32]; p = 0.029) and in multivariable analysis, it remained an independent predictor of DOCE (HR = 3.0; p = 0.018). Conclusions Although, the rates of (potentially) device-related complications following BVS implantation are acceptable, they are nonetheless not negligible. Interestingly, they did not decline over time. Bifurcation stenting could be found as relevant procedure-related predictor of DOCE, especially in ACS patients. Randomized trials are warranted to confirm these findings. [ABSTRACT FROM AUTHOR]

• Metal halide perovskites such as piperidinium hexachlorostannate(IV) and piperidinium hexabromostannate(IV) were prepared along with their ammonium analogues. • Complete analyses with IR, 1H, 13C NMR, DRS techniques. • Band gaps observed in the present study follow the decreasing order: (NH 4) 2 SnCl 6 >(C 5 H 10 NH 2) 2 SnCl 6 >(NH 4) 2 SnBr 6 > (C 5 H 10 NH 2) 2 SnBr 6. • BVS for (NH 4) 2 SnCl 6, (NH 4) 2 SnBr 6, (C 5 H 10 NH 2) 2 SnCl 6, (C 5 H 10 NH 2) 2 SnBr 6 are: 4.12, 4.01, 3.96 and 3.92 respectively, which established the formal oxidation state of tin as quadripositive. • CShM for (NH 4) 2 SnCl 6, (NH 4) 2 SnBr 6, (C 5 H 10 NH 2) 2 SnCl 6, (C 5 H 10 NH 2) 2 SnBr 6 are: 0.000, 0.000, 0.0172 and 0.0103. • Substitution of chlorine with bromine atom in SnX 6 2- anion coalesces the octahedral shape to spherical shape resulting in reduction of band gap. • Piperidinium ion in the place of ammonium ion reduces the band gap due to lattice congestion and the SnX 6 2– anion with the lowest band gap shows spherical Shape index map. Metal halide perovskites such as piperidinium hexachlorostannate(IV) and piperidinium hexabromostannate(IV) were prepared along with their ammonium analogues ((1) and (2)) and were analyzed by IR, 1H, 13C NMR, DRS techniques. Single crystal X-ray structures were determined and Bond valence sums (BVS), Continuous Shape Measure (CShM) parameters were deduced from structural data. Broad IR bands were observed for υ NH2 vibrations (3388, 3383 cm–1) long with characteristic δ NH bending vibrations (1571, 1573 cm–1). TG–DT analysis confirmed the proposed formulae of (1) to (4). Band gaps of the hybrids derived from the DRS study followed the decreasing order: (NH 4) 2 SnCl 6 >(C 5 H 10 NH 2) 2 SnCl 6 >(NH 4) 2 SnBr 6 > (C 5 H 10 NH 2) 2 SnBr 6. Ammonium hybrids (1) & (2) and the piperidinium analogues (3) & (4) are isostructural. Differentiation of Sn-X axial/equatorial bonds and distortion of X–Sn–X bond angles observed in (3) and (4) are due to the substitution of ammonium cation by bulky piperidinium cation. The crystal structures are stabilized by intermolecular N–H···X interactions. BVS for (1), (2), (3) and (4) are: 4.12, 4.01, 3.96 and 3.92 respectively, which established the formal oxidation state of tin as quadripositive. CShM for (1), (2), (3) and (4) are: 0.0000, 0.0000, 0.0172 and 0.0103 respectively, indicating octahedral environment of halogen atoms around tin. Shape Index map of (C 5 H 10 NH 2) 2 SnBr 6 (4) with the least band gap tends to be spherical compared to other compounds. Surface Index maps from Hirshfeld surfaces of (1) to (4) specify that i) substitution of chlorine with bromine atom in SnX 6 2- anion coalesces the octahedral shape to spherical shape leading to reduction in band gap and ii) presence of piperidinium ion in the place of ammonium ion reduces the band gap due to lattice congestion and the SnX 6 2– anion with the lowest band gap shows spherical Shape index map. [Display omitted] [ABSTRACT FROM AUTHOR]

Objectives To investigate one-year outcomes after implantation of a bioresorbable vascular scaffold (BVS) in patients presenting with acute coronary syndrome (ACS) compared to stable angina patients. Background Robust data on the outcome of BVS in the setting of ACS is still scarce. Methods Two investigator initiated, single-center, single-arm BVS registries have been pooled for the purpose of this study, namely the BVS Expand and BVS STEMI registries. Results From September 2012–October 2014, 351 patients with a total of 428 lesions were enrolled. 255 (72.6%) were ACS patients and 99 (27.4%) presented with stable angina/silent ischemia. Mean number of scaffold/patient was 1.55 ± 0.91 in ACS group versus 1.91 ± 1.11 in non-ACS group (P = 0.11). Pre- and post-dilatation were performed less frequent in ACS patients, 75.7% and 41.3% versus 89.0% and 62.0% respectively (P = 0.05 and P = 0.001). Interestingly, post-procedural acute lumen gain and percentage diameter stenosis were superior in ACS patients, 1.62 ± 0.65 mm (versus 1.22 ± 0.49 mm, P < 0.001) and 15.51 ± 8.47% (versus 18.46 ± 9.54%, P = 0.04). Major adverse cardiac events (MACE) rate at 12 months was 5.5% in the ACS group (versus 5.3% in stable group, P = 0.90). One-year definite scaffold thrombosis rate was comparable: 2.0% for ACS population versus 2.1% for stable population (P = 0.94), however, early scaffold thromboses occurred only in ACS patients. Conclusions One-year clinical outcomes in ACS patients treated with BVS were similar to non-ACS patients. Acute angiographic outcomes were better in ACS than in non-ACS, yet the early thrombotic events require attention and further research. [ABSTRACT FROM AUTHOR]

Objectives This study sought to report on clinical outcomes beyond 1 year of the BVS Expand registry. Background Multiple studies have proven feasibility and safety of the Absorb bioresorbable vascular scaffold (BVS) (Abbott Vascular, Santa Clara, California). However, data on medium- to long-term outcomes are limited and available only for simpler lesions. Methods This is an investigator-initiated, prospective, single-center, single-arm study evaluating performance of the BVS in a lesion subset representative of daily clinical practice, including calcified lesions, total occlusions, long lesions, and small vessels. Inclusion criteria were patients presenting with non–ST-segment elevation myocardial infarction, stable/unstable angina, or silent ischemia caused by a de novo stenotic lesion in a native previously untreated coronary artery. Procedural and medium- to long-term clinical outcomes were assessed. Primary endpoint was major adverse cardiac events, defined as a composite of cardiac death, myocardial infarction, and target lesion revascularization. Results From September 2012 to January 2015, 249 patients with 335 lesions were enrolled. Mean number of scaffolds per patient was 1.79 ± 1.15. Invasive imaging was used in 39%. In 38.1% there were American College of Cardiology/American Heart Association classification type B2/C lesions. Mean lesion length was 22.16 ± 13.79 mm. Post-procedural acute lumen gain was 1.39 ± 0.59 mm. Median follow-up period was 622 (interquartile range: 376 to 734) days. Using Kaplan-Meier methods, the MACE rate at 18 months was 6.8%. Rates of cardiac mortality, myocardial infarction, and target lesion revascularization at 18 months were 1.8%, 5.2%, and 4.0%, respectively. Definite scaffold thrombosis rate was 1.9%. Conclusions In our study, BVS implantation in a complex patient and lesion subset was associated with an acceptable rate of adverse events in the longer term, whereas no cases of early thrombosis were observed. [ABSTRACT FROM AUTHOR]

Background: Third-generation drug-eluting metal stents are the gold standard for treatment of coronary artery disease. The permanent metallic caging of the vessel, however, can result in limited vasomotion, chronic inflammation, and late expansive remodeling, conditions that can lead to late and very late stent thrombosis. The development of bioresorbable scaffolds (BRSs) promises advantages over metal stents due to complete biodegradation within 2-4years. Theoretically, since vessel scaffolding is temporary and no permanent implant remains in the vessel, BRSs, as opposed to metal stents, once degraded would no longer be potential triggers for stent-related adverse events or side effects.Methods/design: The short- and long-term outcome after implantation of an everolimus-eluting, poly-L-lactic acid-based bioresorbable scaffold system (ABSORB, Abbott Vascular, Santa Clara, CA, USA) in the world-wide greatest all-comers cohort will be evaluated in the prospective, non-interventional, multicenter German-Austrian ABSORB RegIstRy (GABI-R). GABI-R will include over 5000 patients from about 100 study sites in Austria and Germany. Safety endpoints such as cardiac death, myocardial infarction, and clinically driven percutaneous or surgical target lesion and vessel revascularization will be evaluated during hospitalization and in the follow-up period (minimum of 5years).Conclusion: Although two randomized controlled trials and several registries have documented safety and efficacy as well as non-inferiority of this everolimus-eluting ABSORB device compared with drug-eluting metal stents, the current knowledge regarding clinical application, treatment success, and long-term safety of using this BRS in daily routine is limited. Thus, the goal of GABI-R is to address this lack of information. [ABSTRACT FROM AUTHOR]

This multicenter experience sought to investigate the feasibility and safety of BVS for the treatment of ISR. From April 2012 to June 2014, a total of 315 patients (334 lesions) underwent PCI for ISR at the participating centers. Of those, 83 patients (90 lesions) received BVS. Procedural success was achieved in all patients. At a median of 7 (IQR 3–18) months follow-up, MACCE rate was 12%, TLR 7.7%, while one (1.1%) definite BVS-in-stent thrombosis was reported. The results of this multicenter experience suggest that BVS implantation for the treatment of coronary ISR is technically feasible and associated with favorable mid-term clinical results. These data could be considered hypothesis generating for a future randomized clinical trial. [ABSTRACT FROM AUTHOR]

Background/purpose: Coronary in-stent restenosis (ISR) is a clinical problem for which a satisfactory solution has not been found yet. Bioabsorbable drug eluting vascular scaffolds (BVSs) provide transient vessel scaffolding combined with prolonged drug delivery capability. The aim of this study was to investigate the safety of BVS for the treatment of coronary ISR.Methods/materials: Between January 2013 and June 2013, 27 patients (31 lesions), presenting with either stable or unstable angina due to coronary ISR, were enrolled in a single arm, prospective, open label registry. Primary end point was the occurrence of target vessel revascularization (TVR) at 12 months. Secondary end point was the composite of death, myocardial infarction and TVR at 12 months.Results: A diffuse ISR pattern was present in 70% of the lesions; mean lesion length was 34.6±15. BVS was successfully implanted in all patients with no in hospital MACE. At twelve months of follow up, MACE rate was 18.5%. One patient died for non-cardiac reason, one patient died due to a possible stent thrombosis and TVR was necessary in 3 patients (11.1%).Conclusions: Our data suggest that BVS is safe and technically feasible for treatment of long and diffuse coronary ISR. These data could be considered hypothesis generator for a randomized clinical trial. [ABSTRACT FROM AUTHOR]

Background: The Absorb™ BVS is a bioresorbable, everolimus-eluting scaffold approved and marketed for coronary use. Published data on long-term results after treatment are limited to a small number of patients, most of them with elective PCI of simple lesions. The importance of scaffold resorption is variably appreciated among cardiologists, and indications for use from health technology assessment bodies or guidelines are missing. Instruments are needed to collect, share and assess the experience being accumulated with this new device in several centres.Methods/design: The BVS-RAI Registry is a spontaneous initiative of a group of Italian interventional cardiologists in cooperation with Centro di Ricerche Farmacologiche e Biomediche "Mario Negri" Institute, and is not recipient of funding or benefits originating from the BVS manufacturer. It is a prospective registry with 5-year follow-up of all consecutive patients who have undergone successful implantation of 1 or more coronary BVS following the indications, techniques and protocols used in each of the participating institutions. Outcome measures are BVS target lesion failure within one year and device-oriented major adverse cardiac events within 5years. The registry started in October 2012 and will extend enrolment throughout 2015, with the aim to include about 1000 patients. ClinicalTrials.gov identifier is CT02298413.Conclusions: The BVS-RAI Registry will contribute observational knowledge on the long-term safety and efficacy of the Absorb™ BVS as used in a number of Italian interventional centres in a broad spectrum of settings. Unrewarded and undirected consecutive patient enrolments are key-features of this observation, which is therefore likely to reflect common clinical practice in those centres. [ABSTRACT FROM AUTHOR]

The reaction of equimolar proportions of Na2[PdCl4] and 1-(4-methylimidazol-5-yl) phenylhydrazonopropane-2-one oxime (LH), a 1:1 Schiff-base condensate of 1-hydrazono-1-phenyl-propan-2-one oxime (1) and 4-methylimidazole-5-carboxaldehyde, in methanol gives rise to [Pd(L)(Cl)] (2) in a satisfactory yield. The title monomeric palladium(II) complex, 2, has been characterized by C, H and N microanalyses, 1H and 13C NMR, FAB-MS, FT-IR, UV–Vis spectra, molar electric conductivity measurements and room temperature magnetic susceptibility measurements. The X-ray crystal structures of 1 and 2 have been determined. The structure of 1, a precursor of the ligand (LH), shows that the methyl and phenyl groups are in an ‘anti’ disposition. Compound 1 crystallizes in the monoclinic space group P21 with a =6.9503(5), b =6.4535(3), c =10.1631(6)Å, V =455.04(5)Å3 and Z =2. The structure of 2 reveals that it is a distorted square-planar palladium(II) compound. The palladium center is in an ‘N3Cl’ coordination chromophore. Complex 2 crystallizes in the tetragonal space group I41/a with a =22.5744(3), b =22.5744(3), c =13.2967(2)Å, V =6776.05(16)Å3 and Z =16. The thermal and electrochemical aspects of 2 have been studied. Electrochemical studies in DMF show a Pd(II) to Pd(III) oxidation at 0.573V, along with a reduction of Pd(II) to Pd(I) at −0.757V versus Ag/AgCl. A Bond-Valence Sum (BVS) model calculation was performed to assign the oxidation state of the palladium center in 2. The in vitro antimicrobial activity of 2 was tested against both Gram positive and Gram negative bacteria. Complex 2 exhibits satisfactory bacteriostatic activity. [ABSTRACT FROM AUTHOR]

Developing new polymer-based bioresorbable vascular scaffolds (BVS) requires a new structural geometry, as these polymer materials are characterised by substantially lower stiffness than metallic alloys. Sufficient radial strength of the stent is essential, as insufficient vessel wall support can lead to a significant recoil (reduction of the vessel lumen) and can cause dangerous complications. To assess the stress development and deformation of the stent, finite element analysis (FEA) was used. First, a complex FEA of the inflation and crimping processes of a bioresorbable coronary stent was performed. An optimisation procedure based on the simplified parametric FE model was subsequently performed to obtain the optimal geometric parameters of the analysed structure. The objective of the optimisation was to maximise the vessel diameter after the BVS implantation. The optimisation procedure was based on automatic model-generating scripts, numerical analyses and implementation of genetic algorithms. Finally, a comparison of the parametric and complex models results was performed, as well as a final validation at several stages (structural studies, computational fluid dynamics (CFD) simulations and in vivo testing). The validation confirmed that the presented optimisation methodology represents a valid and useful tool for the stent design process. Unlabelled Image • Development of a new, polymer-based, drug-eluting coronary bioresorbable scaffold (BVS) with improved radial strength. • An optimisation methodology was developed for the bioresorbable stent based on genetic algorithms and parametrically models. • The developed optimisation methodology was validated by analyses of FE BVS models using the CFD and experimental testing. • The BVS structure was subjected to in vivo conditions. [ABSTRACT FROM AUTHOR]

Self assembled organic - inorganic hybrid materials such as morpholinium hexachlorostannate(IV) (3) and morpholinium hexabromostannate(IV) (4) have been synthesised from morpholinium chloride (1) and morpholinium bromide (2) at room temperature. The hybrids were characterized by elemental analysis, IR, NMR, TG-DTA, DRS and PL spectroscopy and single crystal X-ray diffraction. IR and NMR spectral data of (3) and (4) show very little changes compared to their parent compounds (1) and (2). However, the = NH 2 + proton signal of the bromide hybrid (4), shows a relatively lower δ value due to extensive hydrogen bonding compared to its chloride analogue (3). Thermal analysis confirmed the proposed formulae of the compounds. Optical absorption measurements showed 3.80 and 2.60 eV as band gaps for (3) and (4) respectively at room temperature implying that the band gaps can be easily tuned by altering the halide ion. Single crystal X-ray structures of compounds (3) and (4) revealed extensive hydrogen bonded interactions between the morpholinium cation and the SnCl 6 2− and SnBr 6 2− anions in (3) and (4). In (4), two molecules of morpholinium bromide co-crystallized with the hybrid. BVS calculations performed on SnCl 6 2− and SnBr 6 2− anions (3) and (4) resulted in 4.10 and 4.13 respectively, which clearly established the formal oxidation state of tin in the compounds as 4+. CSM calculation on SnBr 6 2− yielded a value of 0.006 signifying a near perfect octahedral geometry of the anion. Image 1 • Room temperature self-assembly of less toxic Tin(IV) – morpholinium hybrids. • Hexahalostannates are capped by morpholinium ions in the unit cell. • BVS established the FOS of tin as +4. • CSM confirmed the near perfect octahedral environment around tin. • Eg for bromo hybrid is 2.60 eV, whereas that of chloro hybrid is 3.80. [ABSTRACT FROM AUTHOR]