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Hybrid Organic‐Inorganic Halide Perovskites (HOIHPs) represent an emerging class of semiconducting materials, widely employed in a variety of optoelectronic applications. Despite their skyrocket growth in the last decade, a detailed understanding on their structure–property relationships is still missing. In this communication, we report two unprecedented perovskite‐like materials based on polyfluorinated imidazolium cations. The two materials show thermotropic liquid crystalline behavior resulting in the emergence of stable mesophases. The manifold intermolecular F ⋅ ⋅ ⋅ F interactions are shown to be meaningful for the stabilization of both the solid‐ and liquid‐crystalline orders of these perovskite‐like materials. Moreover, the structure of the incorporated imidazolium cation was found to tune the properties of the liquid crystalline phase. Collectively, these results may pave the way for the design of a new class of halide perovskite‐based soft materials. [ABSTRACT FROM AUTHOR]

Hybrid Organic‐Inorganic Halide Perovskites (HOIHPs) represent an emerging class of semiconducting materials, widely employed in a variety of optoelectronic applications. Despite their skyrocket growth in the last decade, a detailed understanding on their structure–property relationships is still missing. In this communication, we report two unprecedented perovskite‐like materials based on polyfluorinated imidazolium cations. The two materials show thermotropic liquid crystalline behavior resulting in the emergence of stable mesophases. The manifold intermolecular F ⋅ ⋅ ⋅ F interactions are shown to be meaningful for the stabilization of both the solid‐ and liquid‐crystalline orders of these perovskite‐like materials. Moreover, the structure of the incorporated imidazolium cation was found to tune the properties of the liquid crystalline phase. Collectively, these results may pave the way for the design of a new class of halide perovskite‐based soft materials. [ABSTRACT FROM AUTHOR]

The electronic properties of Mg-O divacancy defects at the MgO surface obtained by removing of a pair of O and Mg ions from terrace, step, or comer sites have been investigated using an embedded cluster model. Long-range polarization and lattice relaxation effects have been included through a shell model approach. It is demonstrated that all these defects are electron traps: an addition of one electron to a neutral precursor results in a stable paramagnetic center. We calculate relaxed electron affinities, vertical ionization energies, formation energies, and hyperfine coupling constants of these defects and discuss their relevance for the interpretation of experimental results on the nature of paramagnetic electronic defects at the surface of MgO. These results further extend a concept of surface electron traps beyond simple anion vacancies to more general structural features. .... [ABSTRACT FROM AUTHOR]

We have studied the optical absorptions of a series of point defects in SiO[sub 2] by means of time-dependent density functional response theory (TD-DFT). The structure of the defects has been described with cluster models and atomic orbital basis functions. For each center the lowest singlet→singlet and singlet→triplet (for diamagnetic defects) and doublet→doublet (for paramagnetic defects) transitions have been considered. The results have been compared with accurate ab initio calculations based on explicit treatment of correlation effects and, when possible, with experimental data. Defects with localized wave functions and low excitation energies (<5 eV) are well described by TD-DFT and the predicted transition energies are within a few tenths of an eV from the experimental or ab initio values. For defects which give rise to transition energies higher than 5 eV the TD-DFT values are 10%–20% too low. The comparison of various exchange-correlation functionals show that the hybrid B3LYP method provides more accurate answers than other gradient-corrected DFT approaches. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Background: Recent data have highlighted a higher rate of neurological injuries in minimal invasive mitral valve surgery (MIMVS) compared with the standard sternotomy approach; therefore, the role of specific clamping techniques and perfusion strategies on the occurrence of this complication is a matter of discussion in the medical literature. The purpose of this trial is to prospectively evaluate major, minor and silent neurological events in patients undergoing right mini-thoracotomy mitral valve surgery using retrograde perfusion and an endoaortic clamp or a transthoracic clamp.Methods/design: A prospective, blinded, randomized controlled study on the rate of neurological embolizations during MIMVS started at the University of Turin in June 2014. Major, minor and silent neurological events are being investigated through standard neurological evaluation and magnetic resonance imaging assessment. The magnetic resonance imaging protocol includes conventional sequences for the morphological and quantitative assessment and nonconventional sequences for the white matter microstructural evaluation. Imaging studies are performed before surgery as baseline assessment and on the third postoperative day and, in patients who develop postoperative ischemic lesions, after 6 months.Discussion: Despite recent concerns raised about the endoaortic setting with retrograde perfusion, we expect to show equivalence in terms of neurological events of this technique compared with the transthoracic clamp in a selected cohort of patients. With the first results expected in December 2016 the findings would be of help in confirming the efficacy and safety of MIMVS.Trial Registration: ClinicalTrials.gov, Identifier: NCT02818166 . Registered on 8 February 2016 - trial retrospectively registered. [ABSTRACT FROM AUTHOR]

Stem-cell-based therapies require a high number (106-109) of cells, therefore in vitro expansion is needed because of the initially low amount of stem cells obtainable from human tissues. Standard protocols for stem cell expansion are currently based on chemically-defined culture media and animal-derived feeder-cell layers, which expose cells to additives and to xenogeneic compounds, resulting in potential issues when used in clinics. The two-photon laser polymerization technique enables three-dimensional micro-structures to be fabricated, which we named synthetic nichoids. Here we review our activity on the technological improvements in manufacturing biomimetic synthetic nichoids and, in particular on the optimization of the laser-material interaction to increase the patterned area and the percentage of cell culture surface covered by such synthetic nichoids, from a low initial value of 10% up to 88% with an optimized micromachining time. These results establish two-photon laser polymerization as a promising tool to fabricate substrates for stem cell expansion, without any chemical supplement and in feeder-free conditions for potential therapeutic uses. [ABSTRACT FROM AUTHOR]

OBJECTIVES Ex vivo lung perfusion (EVLP) is a novel technique used to evaluate and recondition marginal or rejected grafts. Primary graft dysfunction (PGD) is a major early complication after lung transplantation (LTx). The use of marginal or initially rejected grafts may increase its incidence and severity. The aim of this study is to evaluate the incidence of PGD after LTx using rejected grafts reconditioned with EVLP. METHODS PGD has been evaluated immediately after LTx (t0) and after 72 h (t72) in patients receiving standard (Group A) or reconditioned (Group B) grafts. EVLP was performed using a controlled acellular perfusion according to the Toronto technique. RESULTS From July 2011 to February 2013, 36 LTxs have been performed: 28 patients (21 M/7 F, mean age 51.7 ± 14.7 years) in Group A and 8 (6 M/2 F, mean age 46.6 ± 9.8 years) in Group B (successful recondition rate of 73%, 8 of 11 cases). Incidence rate of PGD 3 at t0 and at t72 (Group A versus Group B) was 50 vs 37% (P = NS) and 25 vs 0% (P = NS), respectively. Post-transplant extracorporeal membrane oxygenation was required in 5 and 2 patients in Groups A and B, respectively (P = NS). CONCLUSIONS The use of initially rejected grafts treated with EVLP does not increase the incidence and severity of PGD after LTx. Although comparison of PGD 3 incidence in the two groups did not reach a statistical difference, all EVLP patients suffering from severe PGD early after transplant recovered normal lung function at 72 h, suggesting a protective role of EVLP against PGD occurrence and severity. [ABSTRACT FROM AUTHOR]

Abstract: Background: Re-do mitral valve procedures performed through median sternotomy carry substantial mortality and morbidity. To avoid complications of sternal re-entry and to provide adequate mitral valve exposure, antero-lateral thoracotomy has been suggested by some authors. Methods: From October 1997 to January 2007, 677 mitral valve operations have been performed in our centre using port-access video-assisted right mini-thoracotomy. Among these, 241 (35.6%) were performed on patients who had undergone one or more previous cardiac surgery procedures. Results: Mean cardio-pulmonary bypass time and endo-clamp time were 117±46min and 71±31min, respectively. Arterial cannulation was performed either on the ascending aorta, with the endo-direct cannula (112 patients, 46.5%), or peripherally with a femoral artery approach (129 patients, 53.5%). Conversion to median sternotomy was necessary in only two patients (0.8%) due to aortic dissection (one case) and left ventricle free wall rupture (one case). Median intensive care unit stay was 24h, median mechanical ventilation time was 12h; median hospital stay was 8 days. Bleeding requiring surgical revision occurred in 12 patients (4.9%). Hospital mortality was 4.9% (12/241 patients). Conclusions: Port-access video-assisted right mini-thoracotomy allows good results in a difficult subset of patients; it allows minimal adhesion dissection, short ICU and hospital stay. In our practice, this technique has become the treatment of choice for mitral valve re-do surgery. [Copyright &y& Elsevier]

Abstract: We present a non-conventional, low cost and simple approach for patterning gold nanoparticles (NPs) using highly oriented PolyTetraFluoroEthylene (HOPTFE) macromolecular segments on glass substrates. Transparent and stable HOPTFE templates for NP self-assembly were prepared by sliding unidirectionally a PTFE rod across a glass substrate at a fixed temperature with a constant pressure. Gold NPs, 50 nm nominal core diameter stabilized by citrate and octanethiol, have been assembled onto HOPTFE macromolecular segments using two different procedures. The first method is based on the drop casting of octanethiol capped NPs to obtain a growth of 1-D structures onto HOPTFE ridges. The second method exploits the functionalization of the glass substrate using (3-Aminopropyl)-triethatoxysilane (APTES) in order to induce the formation of 2-D structures between HOPTFE ridges. The self organized nanostructures and their morphological features have been investigated using AFM. The core size distribution of gold NPs was analyzed from TEM images. [Copyright &y& Elsevier]

Abstract: In this work, we investigate the chemical conditions for inducing a self-organized growth of 2D and 1D structures of gold nanoparticles (NPs), 50 nm diameter tri-sodium citrate stabilized, assembled onto chemically modified glass substrates through 3-Aminopropyltriethatoxysilane. The aggregation process of the nanoparticles on the silanised surface has been controlled by optimizing the concentration limit, immersion time and annealing process of NPs. A recipe to obtain the appropriate electrical charge conditions necessary for inducing the dimensionality transition of the organized nanostructures from 2D to 1D has been determined through the comparison between two deposition routes employing different polar solvents (water and ethanol). The self-organized growth of gold NPs into structures of different dimensionality has been extensively investigated by Atomic Force Microscopy and discussed. [Copyright &y& Elsevier]

Abstract: Objective: We studied the concordance of transgene expression in the transplanted heart using bicistronic adenoviral vector coding for a transgene of interest (human carcinoembryonic antigen: hCEA – beta human chorionic gonadotropin: βhCG) and for a marker imaging transgene (human sodium iodide symporter: hNIS). Methods: Inbred Lewis rats were used for syngeneic heterotopic cardiac transplantation. Donor rat hearts were perfused ex vivo for 30min prior to transplantation with University of Wisconsin (UW) solution (n =3), with 109 pfu/ml of adenovirus expressing hNIS (Ad-NIS; n =6), hNIS-hCEA (Ad-NIS-CEA; n =6) and hNIS-βhCG (Ad-NIS-CG; n =6). On postoperative day (POD) 5, 10, 15 all animals underwent micro-single photon emission computed tomography/computed tomography (SPECT/CT) imaging of the donor hearts after tail vein injection of 1000μCi 123I and blood sample collection for hCEA and βhCG quantification. Results: Significantly higher image intensity was noted in the hearts perfused with Ad-NIS (1.1±0.2; 0.9±0.07), Ad-NIS-CEA (1.2±0.3; 0.9±0.1) and Ad-NIS-CG (1.1±0.1; 0.9±0.1) compared to UW group (0.44±0.03; 0.47±0.06) on POD 5 and 10 (p <0.05). Serum levels of hCEA and βhCG increased in animals showing high cardiac 123I uptake, but not in those with lower uptake. Above this threshold, image intensities correlated well with serum levels of hCEA and βhCG (R 2 =0.99 and R 2 =0.96, respectively). Conclusions: These data demonstrate that hNIS is an excellent reporter gene for the transplanted heart. The expression level of hNIS can be accurately and non-invasively monitored by serial radioisotopic SPECT imaging. High concordance has been demonstrated between imaging and soluble marker peptides at the maximum transgene expression on POD 5. [Copyright &y& Elsevier]

Abstract: We analyze transient current data during the formation of titanium oxide nanodots by AFM-tip-induced anodic oxidation with the aim of getting further understanding of local oxidation kinetics. The measured current waveforms show a transition between two distinct regimes, in agreement to what was previously known of the growth process, and their behavior is discussed with respect to the oxide growth rate and to the formation of the space charge. Furthermore, it is shown how the knowledge of the duration of the first transient regime can be exploited to optimize the application of pulsed bias voltages to obtain a substantial improvement in aspect ratio of growing oxides. [Copyright &y& Elsevier]

Introduction: Endomyocardial biopsy is the standard means of establishing cardiac allograft rejection diagnosis. The efficacy of this procedure in xenotransplantation has not been determined. In this study we compare the histology of right ventricular endomyocardial biopsy specimens with the corresponding full cross sections of explanted right ventricle (RV). We also compare RV with the related left ventricle (LV) cross sections. Methods: Heterotopic CD46 pig-to-baboon cardiac xenotransplants (n = 64) were studied. RV endomyocardial biopsy specimens were taken at cardiac explant by using a standard bioptome (n = 24) or by sharp dissection (n = 40). Hematoxylin and eosin stained sections of RV and LV cross-section and RV endomyocardial biopsy specimens were compared in a blinded fashion. Characteristics of delayed xenograft rejection and a global assessment of ischemia were scored from 0 to 4 according to the percentage of myocardium involved (0, 0%; 1, 1%–25%; 2, 26%–50%; 3, 51%–75%; and 4, 76%–100%). Results: Median graft survival was 30 days (range, 3–137 days). Linear regression analysis of histology scores demonstrated that specimens from both bioptome and sharp dissection equally represented the histology of the RV cross section. Global ischemic injury was strongly correlated between RV and RV endomyocardial biopsy (R 2 = 0.84) and between RV and LV cross sections (R 2 = 0.84). Individual characteristics of delayed xenograft rejection showed no significant variation between RV and RV endomyocardial biopsy or between RV and LV (p < 0.05). Conclusions: These results indicate that delayed xenograft rejection is a widespread process involving both right and left ventricles similarly. This study shows that histologic assessment of RV endomyocardial biopsy specimens is an effective method for the monitoring of delayed xenograft rejection after cardiac xenotransplantation. [Copyright &y& Elsevier]

Abstract: The fabrication of single electron transistors and/or highly sensitive biosensors is still a challenging task on account of the tight control required to get proper shapes and size of the electrodes. The nanosized tips and the separation of a few nanometers between electrode pairs are critical features. Conventional lithography is not suited to obtain these features because of the resolution limits, so that previous alternative approaches have involved the use of electron beam lithography, focused ion beam lithography or scanning probe nanolithography. The novel approach presented in this letter is the exploitation of X-ray lithography in the Elettra synchrotron to fabricate arrays of nanocontacts spaced a few nanometers, devoted to the design of a new class of nanodevices based on nanoparticles and/or single molecules, including single electron transistors and highly sensitive biosensors. The method to fabricate such devices is illustrated and discussed. Experimental details of the fabrication process are given and preliminary results are presented through SEM and AFM images. It is worth noting that this paper presents a viable method to produce nanocontacts by using the X-ray lithography by synchrotron radiation source, that has not yet been reported together with experimental, though preliminary, data. [Copyright &y& Elsevier]

Abstract: The structure and the vibrational properties of ultra-thin SiO2 films (one to three layers, 1–3L) epitaxially grown on a Mo(112) substrate have been determined by first principle DFT calculations. For 2L and 3L films the structures considered are derived from those of β-cristobalite, β-tridymite, α- or β-quartz; for 1L films we considered regular arrays of isolated SiO4 tetrahedra, one-dimensional (SiO3) n chains, or an hexagonal two-dimensional (SiO2.5) structure. The 1L films have the c(2×2) pattern observed experimentally. On the basis of the comparison of the computed frequencies with IR and HREEL spectra, of the existing data on film thickness, periodicity, and surface reactivity, we conclude that the film consists of a single silica layer with hexagonal c(2×2) structure. [Copyright &y& Elsevier]

We have considered the interaction of O2 and N2 molecules with electrons trapped at the surface of MgO by performing embedded cluster DFT calculations. Trapped electrons at the surface of MgO react instantaneously with O2 and N2 leading to the formation of the corresponding O2− and N2− molecular anions stabilized at specific surface sites. So far, the atomistic model for this process was based on the idea that the electrons are trapped at oxygen vacancies, the FS+ centers. Recently, it has been shown that morphological sites at the MgO surface like a reverse corner, a step or a corner, can adsorb hydrogen and stabilize (H+)(e−) pairs giving rise to a new class of paramagnetic color centers. Here we show that these centers exhibit reactivity towards O2 and N2, which is fully consistent with the experimental observations, providing further support to the new model of electron traps at the MgO surface. [Copyright &y& Elsevier]

On the basis of embedded cluster calculations, we propose a new model for the structure of paramagnetic color centers at the MgO surface usually denoted as F[sub S](H)[sup +] (an electron trapped near an adsorbed proton). These centers are produced by exposing the surface of polycrystalline MgO to H[sub 2] followed by UV irradiation. We demonstrate that properties of H atom absorbed at surface sites such as step edges (MgO[sub step]) and reverse corner sites (MgO[sub RC]), formed at the intersection of two step edges, are compatible with a number of features observed for F[sub S](H)[sup +]. Our calculations suggest that (i) H[sub 2] dissociates at the reverse corner site heterolytically and that there is no barrier for this exothermic reaction; (ii) the calculated vibrations of the resulting MgO[sub RC](H[sup +])(H[sup -]) complex are fully consistent with the measured ones; (iii) desorption of a neutral H atom from the diamagnetic precursor requires UV light and leads to the formation of stable neutral paramagnetic centers at the surface, MgO[sub step](H[sup +])(e[sup -])[sub trapped] and MgO[sub RC](H[sup +])(e[sup -])[sub trapped]. The computed isotropic hyperfine coupling constants and optical transitions of these centers are in broad agreement with the existing experimental data. We argue that these centers, which do not belong to the class of "oxygen vacancies", are two of the many possible forms of the F[sub S](H)[sup +] defect center. [ABSTRACT FROM AUTHOR]

O− species obtained as hole centers, generated via X-ray irradiation of polycrystalline MgO,O2−(s)+hν→O−(s)+(e−)trappedare compared to the same chemical species generated via bleaching of the surface colour centers with N2O,(e−)trapped+N2O(g)→O−(s)+N2(g)The electron paramagnetic resonance (EPR) spectrum of the former species presents a single, well defined feature which corresponds to one of the several species present in the complex O− spectrum, obtained by reaction with N2O. The O− and the trapped electron, formed upon X-ray irradiation, decay simultaneously indicating that a recombination process takes place and that they are not too far apart. EPR parameters have been determined by quantum-mechanical calculations for a variety of possible electron rich sites on which an oxygen atom adsorbs. It is found that both oxygen vacancies and morphological sites on the MgO surface fulfill the spectroscopic characteristics of the electron trapping sites probed by the O− radical ion. A new model for a paramagnetic Fs+(H) colour center has been proposed as a possible morphological electron trap where an oxygen atom is adsorbed. Thermochemical measurements for the reaction of (e−)trapped with N2O give an average reaction enthalpy of 450±50 kJ mol−1, which is in reasonable agreement with the computed values. [Copyright &y& Elsevier]

We describe the performance, in one surgical session, of bilateral pulmonary endarterectomy and a button-technique Bentall operation in a 68-year-old man. The patient had chronic thromboembolic pulmonary hypertension and an ascending aortic aneurysm with moderate aortic regurgitation. The procedures were concurrently completed during short periods of systemic circulatory arrest, with antegrade cerebral perfusion maintained through the brachiocephalic artery at a flow rate of 10 mL/min/kg. The patient's cerebral perfusion was monitored with use of near-infrared spectroscopy, to prevent symmetric bilateral values from falling below 20% of the base value. The patient experienced no multiorgan failure or neurologic sequelae and, by the 6th postoperative day, improved from New York Heart Association functional class IV to class I. The reliable maintenance of continuous antegrade cerebral perfusion made the lengthy combined operation feasible, with low risk. The use of near-infrared spectroscopy enabled real-time monitoring of the patient's cerebral blood flow. Our experience shows the possibility of safely performing lengthy or multiple procedures in one surgical session. (Tex Heart Inst J 2012;39(5):744-6) [ABSTRACT FROM AUTHOR]

Extramedullary haematopoiesis (EMH) is the development of haematopoietic tissue outside the bone marrow and it most often occurs in the liver and spleen. Renal EMH is quite rare and there are very few case reports concerning the kidney. We describe two cases of ‘renal histologically documented EMH’ and, in particular, in the second of these two, the EMH tissue coexists with a clear cell renal carcinoma. Although rare, these clinical pictures raise some questions about the role of needle biopsy in the management of renal masses that present a diagnostic dilemma, especially in cases without involvement of other abdominal or intrathoracic organs. [ABSTRACT FROM PUBLISHER]

Abstract: In a recent paper by Chen and Goodman [M. Chen, D.W. Goodman, Surf. Sci. 600 (2006) L255] the structure of SiO2 films epitaxially grown on Mo(112) has been revisited. This structure has been the subject of several experimental and theoretical studies but it is still controversial, with some authors claiming that it is formed by isolated [SiO4] units and others in favor of a two-dimensional [Si–O–Si] network. With this Comment we want do underline some aspects of the discussion, in particular related to the theoretical work performed so far on this subject, which in our opinion have not been properly represented in Ref. [M. Chen, D.W. Goodman, Surf. Sci. 600 (2006) L255]. [Copyright &y& Elsevier]

Embedding methods specifically designed to treat large molecules with bulky ligands or in polar solvents are used to describe the electronic structure of point defects in the covalently bonded solids SiO[sub 2], Si[sub 3]N[sub 4], and Si[sub 2]N[sub 2]O. The mechanical relaxation of the lattice around a given defect, in particular an anion vacancy or interstitial, is described using the ONIOM approach where the system is partitioned in two regions, the local defect treated at the gradient corrected DFT level, and the surrounding matrix treated with a semiempirical Hamiltonian. In this way clusters of 100 atoms and more are used to describe a portion of the solid of 10-15 Å of diameter. The long-range lattice polarization induced by a charged defect, a charged oxygen vacancy or a proton bound to O or N atoms, is estimated by means of the isodensity polarized continuum model, IPCM, and compared with the approximate Born's formula. The two simplified embedding schemes provide a simple way to improve cluster models of neutral and charged defects in covalent materials. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article related to lung transplantation (LTx) in the previous issue.

Nonsense mutations cause several genetic diseases such as cystic fibrosis, Duchenne muscular dystrophy, β-thalassemia, and Shwachman–Diamond syndrome. These mutations induce the formation of a premature termination codon (PTC) inside the mRNA sequence, resulting in the synthesis of truncated polypeptides. Nonsense suppression therapy mediated by translational readthrough-inducing drugs (TRIDs) is a promising approach to correct these genetic defects. TRIDs generate a ribosome miscoding of the PTC named "translational readthrough" and restore the synthesis of full-length and potentially functional proteins. The new oxadiazole-core TRIDs NV848, NV914, and NV930 (NV) showed translational readthrough activity in nonsense-related in vitro systems. In this work, the possible off-target effect of NV molecules on natural termination codons (NTCs) was investigated. Two different in vitro approaches were used to assess if the NV molecule treatment induces NTC readthrough: (1) a study of the translational-induced p53 molecular weight and functionality; (2) the evaluation of two housekeeping proteins' (Cys-C and β2M) molecular weights. Our results showed that the treatment with NV848, NV914, or NV930 did not induce any translation alterations in both experimental systems. The data suggested that NV molecules have a specific action for the PTCs and an undetectable effect on the NTCs. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Prosthetic valve endocarditis (PVE) is an uncommon yet dreadful complication in patients with prosthetic valves that requires a distinct analysis from native valve endocarditis. The present study aims to investigate independent risk factors for early surgical outcomes in patients with PVE. METHODS: A retrospective cohort study was conducted in 8 Italian Cardiac Surgery Units from January 2000 to December 2013 by enrolling all PVE patients undergoing surgical treatment. RESULTS: A total of 209 consecutive patients were included in the study. During the study period, the global rate of surgical procedures for PVE among all operations for isolated or associated valvular disease was 0.45%. Despite its rarity this percentage increased significantly during the second time frame (2007-2013) in comparison with the previous one (2000-2006): 0.58% vs 0.31% (P < 0.001). Intraoperative and in-hospital mortality rates were 4.3% and 21.5%, respectively. Logistic regression analysis identified the following factors associated with in-hospital mortality: female gender [odds ratio (OR) = 4.62; P < 0.001], shock status (OR = 3.29; P = 0.02), previous surgical procedures within 3 months from the treatment (OR = 3.57; P = 0.009), multivalvular involvement (OR = 8.04; P = 0.003), abscess (OR = 2.48; P = 0.03) and urgent surgery (OR = 6.63; P < 0.001). CONCLUSIONS: Despite its rarity, PVE showed a significant increase over time. Up to now, in-hospital mortality after surgical treatment still remains high (>20%). Critical clinical presentation and extension of anatomical lesions are strong preoperative predictors for poor early outcome. [ABSTRACT FROM AUTHOR]

Background: The relationship between retrograde arterial perfusion and stroke in patients with peripheral vascular disease has been widely documented. Antegrade arterial perfusion has been favoured as an alternative approach in less invasive mitral valve (MV) operations. We aimed to analyse our experience in patients with peripheral arterial disease undergoing MV surgery through a right mini-thoracotomy adopting antegrade arterial perfusion.Method: A single-institution retrospective study on prospectively collected data was performed on patients undergoing right mini-thoracotomy MV surgery with antegrade arterial perfusion. Since 2009, indication for the latter was dictated by the severity of atherosclerotic burden. Preoperative screening included computed tomography, angiography, or both for the evaluation of the aorta and ileo-femoral arteries.Results: Consecutive patients (n=117) underwent MV surgery through a right mini-thoracotomy with antegrade arterial perfusion, established either by transthoracic central aortic cannulation in 65 (55.6%) cases or by axillary arterial cannulation in 52 (44.4%). Mean logistic EuroSCORE was 11%±2.3%. Twenty-five (25) (21.4%) patients had undergone one or more previous cardiac operations. Operative mortality was 4.3% (n=5). Nonfatal iatrogenic aortic dissection occurred in one case (0.8%). The incidence of stroke was zero.Conclusions: Axillary or central aortic cannulation is a promising alternative route to provide excellent arterial perfusion in right mini-thoracotomy MV surgery, with a very low incidence of stroke and other major perioperative complications in patients with severe aortic or peripheral arterial disease. [ABSTRACT FROM AUTHOR]

Bucky gel actuators are one of the most promising type of electrochemical actuators based on carbon nanotubes (CNTs). They are lightweight, they are able to work in air without any liquid electrolyte and require just few volts to operate. In order to find real world applications where bucky gel actuators can outperform conventional motors, there are still some issues to be addressed. One key aspect in CNT-based electrochemical actuators is that their actuation speed is limited by the ability of charging and discharging the device without exceeding the electrochemical stability window of the electrolyte. This speed is macroscopically related with the product of the resistance and the capacitance of the equivalent circuit (circuit time constant), and with the ion diffusion speed inside the active electrodes. To enhance the actuator performance it is necessary to increase the ion drift current in the electrolyte avoiding to significantly raise the voltage at the electrodes and shorten the ion path necessary to charge the bucky gel electrodes. By proper material processing, we have successfully addressed this issue. A reduced thickness of the actuators to one third of the original size results in a one order of magnitude increase both of the strain at higher frequencies and of the maximum operating frequency. [ABSTRACT FROM AUTHOR]

Abstract: We investigate the effect of different voltage waveforms on the growth of titanium oxide nanodots using Atomic Force Microscope (AFM) nanolithography. The resulting oxide features are compared by taking into account the current data detected during oxidation under the application of constant and linear ramp voltages. The experimental analysis of current waveforms during oxidation upon a constant bias voltage gives quantitative criteria to reduce space charge effects. The use of ramp voltages gives higher flexibility on the control of volume and aspect ratio of oxide features by varying the duty cycle. [Copyright &y& Elsevier]

Background: In this investigation we studied the efficacy and durability of recombinant adeno-associated virus serotype 9 (rAAV9) vector–mediated gene transfer to the transplanted rat heart. Methods: A rAAV9-CMV-lacZ vector diluted in cold (4°C) University of Wisconsin solution was used to perfuse the rat coronary vasculature for 20 minutes prior to syngeneic heterotopic transplantation. Perfusion experiments (six groups, n = 3/group) were performed without rAAV9 and at four separate doses ranging from 2 × 109 to 2 × 1012 viral genomes/ml. The transplanted heart was recovered 10 days or 3 months after transplantation and expression of lacZ assessed by histology, enzyme-linked immunoassay and real-time reverse transcript–polymerase chain reaction (RT-PCR). In a final group (n = 3), rAAV9 was administered systemically to compare the cardiac transduction efficiency and viral distribution to other organs. Results: Transduction efficiency of perfused virus correlated with vector dose (p < 0.0001), with myocardial transduction ranging up to 71.74% at the highest dose. Cardiac expression of lacZ was equivalent at 10 days and 3 months. There was no evidence of viral gene transfer to other organs after heart transplantation. Conclusions: Our findings demonstrate efficient and durable rAAV9-mediated gene transfer to the transplanted heart after ex vivo perfusion and suggest that AAV9 is a promising vector for cardiac gene therapy. [Copyright &y& Elsevier]

Abstract: Single-wall carbon nanotubes (SWCNTs) are one of the most interesting materials for transparent conductive films. In this work, we show our latest results on growth of transparent nanotube networks on quartz and silicon dioxide, and a new process to make a solid-to-solid direct transfer of these networks on a polycarbonate film to obtain, at room temperature, a conductive transparent material. [Copyright &y& Elsevier]

Background: Adenovirus serotype 5 has remained the pre-eminent vector in pre-clinical gene therapy applications in cardiac transplantation. Concerns over the potential effects of adenoviral vectors on the later development of cardiac allograft vasculopathy (CAV) are addressed in this study. Methods: Hearts (n = 22) harvested from Brown Norway rats were perfused ex vivo with either University of Wisconsin (UW) solution with no virus, Ad-CMV-LacZ or Ad-CMV-Null. Donor hearts were transplanted heterotopically into the abdomen of Lewis rats. All recipients received cyclosporine for the duration of the experiment. Transplanted hearts were recovered for analysis at 120 days. Sections of the heart were stained with elastic–van Gieson stain for morphometric analysis of the vessels to ascertain the degree of vascular luminal occlusion. Hematoxylin–eosin staining facilitated diagnosis of chronic rejection. Results: Seventy-seven percent of transplanted hearts showed signs of chronic rejection with no difference in the proportion of animals between groups (p = 0.797). No difference was noted in the degree of vascular luminal occlusion between the Ad-Null (0.57 ± 0.22), Ad-LacZ (0.62 ± 0.19) and UW (0.47 ± 0.29) groups (p = 0.653). Conclusions: Vascularized cardiac allografts transplanted from Brown Norway to Lewis rats demonstrated cardiac allograft vasculopathy CAV at 120 days. Adenoviral perfusion of the donor heart ex vivo did not affect the development of CAV. [Copyright &y& Elsevier]

Abstract: Nanocomposite materials of poly(o-anisidine) (POAS) containing titanium dioxide nanoparticles (TiO2), carbon black (CB) and multi-walled carbon nanotubes (MWNT) were prepared. The synthesized materials were deposited in thin films in order to investigate their impedance characteristics by comparison. Electrochemical impedance spectroscopy (EIS) study was performed using the prepared films as working electrodes in a three electrodes configuration cell. Comparison between the fitting parameters was carried out in order to identify the improved nanocomposite for biosensor applications. [Copyright &y& Elsevier]

The aim of this work is to fabricate ordered arrays of thiolated gold nanoparticles grafted through electrically conductive molecular tethers onto gold electrodes.Dodecanethiol-capped gold nanoparticles were synthesized in a two-phase liquid–liquid system. Cluster size selection by the vapor transfer technique was repeatedly performed in order to obtain a narrow nanoparticle core diameter distribution that peaked around 2 nm. Transmission electron microscopy (TEM) imaging of drop cast films prepared onto carbon-coated grids allowed us to assess the performance of each fractionalization process step and the corresponding particle aggregation behavior.A 1,4-benzenedimethanethiol self-assembled film onto hetero-epitaxial gold on mica has been chosen as a grafting substrate for size-selected gold nanocluster films. Using an air, room temperature scanning tunneling microscopy (STM), the behavior of drop cast and Langmuir nanocluster films onto this substrate was investigated. Better results in terms of adhesion and 2-D aggregation were obtained in the case of Langmuir films. This performance has been further enhanced by application of the multi-step creep method during the Langmuir film making. [Copyright &y& Elsevier]

Abstract: We show how the analysis of the current detected during the fabrication of titanium oxide dots by AFM local anodic oxidation allows the determination of the optimal duration of bias voltage for obtaining nanostructures with higher aspect ratio. Experimental conditions to fabricate oxide dots and lines are discussed. Finally, we demonstrate that proper values of scan rate and period of a pulsed bias voltage enables the selective oxidation of dots and lines. [Copyright &y& Elsevier]

The topographic map of motor cortical representation, called the motor map, is not invariant, but can be altered by motor learning, neurological injury, and functional recovery from injury. Although much attention has been paid to short-term changes of the motor map, robust measures have not been established. The existing mapping methods are time-consuming, and the obtained maps are confounded by time preference. The purpose of this study was to examine the dynamics of the motor map on a timescale of minutes during transient somatosensory input by a fast motor mapping technique. We applied 32-channel micro-electrocorticographic electrode arrays to the rat sensorimotor cortex for cortical stimulation, and the topographic profile of motor thresholds in forelimb muscle was identified by fast motor mapping. Sequential motor maps were obtained every few minutes before, during, and just after skin stimulation to the dorsal forearm using a wool buff. During skin stimulation, the motor map expanded and the center of gravity of the map was shifted caudally. The expansion of the map persisted for at least a few minutes after the end of skin stimulation. Although the motor threshold of the hotspot was not changed, the area in which it was decreased appeared caudally to the hotspot, which may be in the somatosensory cortex. The present study demonstrated rapid enlargement of the forelimb motor map in the order of a few minutes induced by skin stimulation. This helps to understand the spatial dynamism of motor cortical representation that is modulated rapidly by somatosensory input. • Rat forelimb motor map expanded during a few minutes of skin brush stimulation. • The expansion of the motor map persisted for a few minutes after skin stimulation. • Motor threshold in the somatosensory cortex might be decreased by skin stimulation. [ABSTRACT FROM AUTHOR]

Localized drug delivery represents one of the most challenging uses of systems based on conductive polymer films. Typically, anionic drugs are incorporated within conductive polymers through electrostatic interaction with the positively charged polymer. Following this approach, the synthetic glucocorticoid dexamethasone phosphate is often delivered from neural probes to reduce the inflammation of the surrounding tissue. In light of the recent literature on the neuroprotective and anti‐inflammatory properties of tauroursodeoxycholic acid (TUDCA), for the first time, this natural bile acid was incorporated within poly(3,4‐ethylenedioxythiophene) (PEDOT). The new material, PEDOT—TUDCA, efficiently promoted an electrochemically controlled delivery of the drug, while preserving optimal electrochemical properties. Moreover, the low cytotoxicity observed with viability assays, makes PEDOT–TUDCA a good candidate for prolonging the time span of chronic neural recording brain implants. From bears to brain: The Food and Drug Administration approved hydrophilic bile acid tauroursodeoxycholic acid (TUDCA) was successfully incorporated in electrodeposited PEDOT films. This study was aimed at the realization of a new PEDOT–TUDCA composite material that may result a potential substitute of the synthetic glucocorticoids for localized drug delivery system in neuroscience applications. [ABSTRACT FROM AUTHOR]

Background/Aims: Many potentially toxic molecules accumulate in the blood during hepatic dysfunction. In clinical practice, it is very difficult to remove bilirubin, the most widely studied toxin, and particularly the unconjugated form, strongly albumin-bound. The aim of this in vitro study was to assess irreversible bilirubin adsorption as a protein-bound compound marker, using Cytosorb® (Cytosorbents Corp.), a new hemoadsorption device designed to remove cytokines. Methods: We performed 4 in vitro experiments, dynamic and static, with different albumin-bilirubin solutions. Results: All experiments showed the resin's ability to break the albumin-bilirubin complex (Experiment 1, 2), leading to efficient bilirubin removal for 24 h (Removal Rate: 90% Experiment 3) with minimal albumin loss. No sign of bilirubin release from the charged resin was detected (Experiment 4). Conclusion: Cytosorb® seems a promising artificial liver support, thanks to its ability to adsorb bilirubin and its proven ability to modulate the cytokines involved in hepatic dysfunction. [ABSTRACT FROM AUTHOR]

Oxidized single walled carbon nanohorns (ox-SWCNH) were electrodeposited onto gold microelectrode arrays in conjunction with poly(3,4-ethylenedioxythiophene) (PEDOT) and polystirenesulfonate (PSS), and the properties of the new composite material for neural recording and stimulation were assessed. PEDOT/ox-SWCNH composites were compared with films prepared with one of the most notorious carbonaceous material in this field, the oxidized multi-walled Carbon Nanotubes (ox-MWCNT). The PEDOT/ox-SWCNH exhibited superior charge transfer capability, reflecting greater electroactive surface, as confirmed by SEM and EIS characterizations. As a consequence, a charge injection limit of 11.6 mC/cm 2 was observed for the new composite, which is higher than the one of PEDOT/ox-MWCNT (8.7 mC/cm 2 ). Having confirmed comparable neural recording performance, the PEDOT/ox-SWCNH composite results very promising for improving therapeutic electrical stimulation in the central and peripheral nervous systems. [ABSTRACT FROM AUTHOR]

Abstract: PEDOT (Poly(3,4‐ethylenedioxythiophene)) is one of the most promising electrode materials for biomedical applications like neural recording and stimulation, thanks to its enhanced biocompatibility and electronic properties. Drug delivery by PEDOT is typically achieved by incorporating drugs as dopants during the electrodeposition procedure and a subsequent release can be promoted by applying a cathodic trigger that reduces PEDOT while enabling the drug to diffuse. This approach has several disadvantages including, for instance, the release of contaminants mainly due to PEDOT decomposition during electrochemical release. Herein we describe a new strategy based on the formation of a chemical linkage between the drug and the conductive polymer. In particular, dexamethasone was successfully integrated into a new electropolymerized PEDOT–Dex composite, leading to a self‐adjusting drug release system based on a biochemically hydrolysable bond between dexamethasone and PEDOT. [ABSTRACT FROM AUTHOR]

Key points The cortical mechanisms of grasping have been extensively studied in macaques and humans; here, we investigated whether common marmosets could rely on similar mechanisms despite strong differences in hand morphology and grip diversity., We recorded electrocorticographic activity over the sensorimotor cortex of two common marmosets during the execution of different grip types, which allowed us to study cortical activity (power spectrum) and physiologically inferred connectivity (phase-slope index)., Analyses were performed in beta (16-35 Hz) and gamma (75-100 Hz) frequency bands and our results showed that beta power varied depending on grip type, whereas gamma power displayed clear epoch-related modulation., Strength and direction of inter-area connectivity varied depending on grip type and epoch., These findings suggest that fundamental control mechanisms are conserved across primates and, in future research, marmosets could represent an adequate model to investigate primate brain mechanisms., Abstract The cortical mechanisms of grasping have been extensively studied in macaques and humans. Here, we investigated whether common marmosets could rely on similar mechanisms despite striking differences in manual dexterity. Two common marmosets were trained to grasp-and-pull three objects eliciting different hand configurations: whole-hand, finger and scissor grips. The animals were then chronically implanted with 64-channel electrocorticogram arrays positioned over the left premotor, primary motor and somatosensory cortex. Power spectra, reflecting predominantly cortical activity, and phase-slope index, reflecting the direction of information flux, were studied in beta (16-35 Hz) and gamma (75-100 Hz) bands. Differences related to grip type, epoch (reach, grasp) and cortical area were statistically assessed. Results showed that whole-hand and scissor grips triggered stronger beta desynchronization than finger grip. Task epochs clearly modulated gamma power, especially for finger and scissor grips. Considering effective connectivity, finger and scissor grips evoked stronger outflow from primary motor to premotor cortex, whereas whole-hand grip displayed the opposite pattern. These findings suggest that fundamental control mechanisms, relying on adjustments of cortical activity and connectivity, are conserved across primates. Consistently, marmosets could represent a good model to investigate primate brain mechanisms. [ABSTRACT FROM AUTHOR]

High-density surface microelectrodes for electrocorticography (ECoG) have become more common in recent years for recording electrical signals from the cortex. With an acceptable invasiveness/signal fidelity trade-off and high spatial resolution, micro-ECoG is a promising tool to resolve fine task-related spatial-temporal dynamics. However, volume conduction - not a negligible phenomenon - is likely to frustrate efforts to obtain reliable and resolved signals from a sub-millimeter electrode array. To address this issue, we performed an independent component analysis (ICA) on micro-ECoG recordings of somatosensory-evoked potentials (SEPs) elicited by median nerve stimulation in three human patients undergoing brain surgery for tumor resection. Using well-described cortical responses in SEPs, we were able to validate our results showing that the array could segregate different functional units possessing unique, highly localized spatial distributions. The representation of signals through the root-mean-square (rms) maps and the signal-to-noise ratio (SNR) analysis emphasizes the advantages of adopting a source analysis approach on micro-ECoG recordings in order to obtain a clear picture of cortical activity. The implications are twofold: while on one side ICA may be used as a spatial-temporal filter extracting micro-signal components relevant to tasks for brain-computer interface (BCI) applications, it could also be adopted to accurately identify the sites of nonfunctional regions for clinical purposes. [ABSTRACT FROM AUTHOR]

Carbon nanotube actuators possess the requirements to be used in soft robotic applications as they are lightweight, simple to assemble and can operate at low voltage. However, there is still a need to further enhance their performances—in particular strain and blocking force—in order to render their implementation in devices more viable. In this study, we report the electrochemical and electromechanical properties of carbon nanotube-polymer actuators containing metal chalcogenides (BN, WS 2 and MoS 2 ). We demonstrate that the incorporation of such particles in the carbon-based electrodes results in a remarkable increase of the actuators’ performances. Indeed, by tuning the amount of metal chalcogenides, we improve both the strain and blocking force responses of the actuators by 60%. [ABSTRACT FROM AUTHOR]

Bucky gel actuators are typically fabricated by having an electrolyte layer sandwiched by two carbon nanotubes electrodes. They possess outstanding electrical and mechanical properties thanks to their composition, which make them very attractive for robotics applications. Even though carbon nanotube electrodes have been extensively studied in the recent years, the electrolyte layer has not been investigated in depth yet. In this study, we demonstrate that the performances (strain and blocking force) of carbon nanotubes actuators can be improved by tuning the electrolyte layer composition. The viscosity and the ionic conductivity of various binary solvent–ionic liquid mixtures (ethylene glycol, polyethylene glycol, acetonitrile, propylene carbonate, 4-methyl-2-pentanone as solvents and 1-butyl-3-methylimidazolium tetrafluoroborate as the ionic liquid) were first examined and used as key parameters to select the optimal electrolyte layer composition. We observed a remarkable increase of strain and blocking force when the ionic conductivity and the viscosity of the electrolyte were maximum and minimum respectively. [ABSTRACT FROM AUTHOR]

A series of novel poly(ionic liquid)s/carbon nanotubes composites were prepared and studied. The effect of the anion on the thermal, mechanical and electrical properties of the composites was investigated. We obtained electrical conductivities ranged from 20 to 40 S cm −1 which are amongst the highest reported for a material involving poly(ionic liquid)s and carbon nanotubes only. Dry electrochemical actuators were successfully prepared using poly(ionic liquid)s composites as electrodes, without the use of a polymer support such as polyvinylidene difluoride. It was found that the anion size influences the displacement response of the actuator. A maximum bending displacement of up to 0.5 mm was recorded under a low applied voltage of ±1 V. [ABSTRACT FROM AUTHOR]

Background Extracorporeal membrane oxygenation (ECMO) is a life-saving bridging procedure in patients with severe acute respiratory distress syndrome (ARDS). Official indications for ECMO are unclear for immunocompromised and HIV-positive patients affected by severe hypoxemia. Uncertainties are related to prognosis and efficacy of treatment of the underlying disease. However, the care of patients with HIV infection has advanced since the introduction of highly active antiretroviral therapy (HAART), with increased life expectancy and decreased mortality. Case presentation Three HIV-infected patients with AIDS were admitted to ICU and were treated with ECMO: a 21 years old Caucasian female with congenital HIV infection presented with Pneumocystis jirovecii pneumonia (PJP); a 38 years old Caucasian female with HIV-HCV infection and L. pneumophila pneumonia; a 24 years old Caucasian male with fever, cough weight loss and PJP pneumonia. Two patients were alive, with a good immunovirological profile and they went back to their previous quality of life. The last patient died with septic shock after three months of ICU stay. Conclusion ECMO was effective in three HIV-positive patients with an otherwise fatal respiratory failure. All patients had severe immunosuppression and/or limited antiretroviral options. A multidisciplinary critical team is needed to individualize the use of ECMO in immunocompromised patients, including those with HIV infection. [ABSTRACT FROM AUTHOR]

Abstract: Flexible sensors are gaining increasing interest in a number of applications, including biomedical, food control, domotics and robotics, having very light weight, robustness and low cost. In order to improve signal-to-noise ratio, integration of readout electronics is crucial and several technologies are available for the fabrication of thin film transistors (TFTs) based circuits on flexible substrates. Among these technologies, the low temperature polycrystalline silicon (LTPS) is particularly attractive, since LTPS TFTs show excellent electrical characteristics, good stability and offer the possibility to exploit CMOS architectures. The different aspects for the direct fabrication of LTPS TFTs on polymer substrates are reviewed and the specific fabrication process adopted on ultrathin polyimide substrates is described in some detail. Then, as examples of flexible sensing systems, we present both chemical and physical sensors integrated with LTPS TFTs frontend electronics. The present results can pave the way to advanced flexible sensing systems, where sensors and local signal conditioning circuits can be integrated on the same flexible substrate. [Copyright &y& Elsevier]

Abstract: Oxidative polymerization of pyrrole directly on preformed bucky gel slurry was carried out in order to combine the remarkable properties of ionic actuators based on carbon nanotubes and polypyrrole. Bimorph solid state ionic actuators were prepared with this novel hybrid material and compared with classical bucky gel actuators. A small amount of polypyrrole is sufficient to dramatically improve the overall actuator performance. The maximum strain is five times larger than the one of actuators prepared only with carbon nanotubes. Moreover, for the same applied charge, the strain generated increases up to twenty-five times. [Copyright &y& Elsevier]

Abstract: Waste polypropylene (PP) is used as precursor for synthesizing multi-walled carbon nanotubes (MWCNTs) by single stage chemical vapor deposition (CVD) method using nickel as catalyst. The pyrolytic degradation of PP to MWCNT was achieved by exposing the catalyst and precursor to temperature 600,700 and 800°C under argon and hydrogen atmosphere for an hour. The resultant carbon was purified and characterized by XRD, Raman scattering, SEM, TEM and HRTEM. All the analysis confirmed the graphitic nature and multi-walled morphology of the CNT. Moreover the MWCNT was found to exhibit high transmittance to visible light up to 85% at 550nm, comparable to that of typical ITO films (90%), suggesting that MWCNTs can be used for optoelectronic devices. The present work could be employed for synthesizing CNTs, having wide range of applications, and for environment protection as well since waste plastic is being used. [Copyright &y& Elsevier]