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Background: Kidney transplantation (KT) is the treatment of choice for patients with end-stage renal disease (ESRD). General organ donor shortage remains an important limitation on KT, given the increasing number of patients waiting for transplantation. This has led to the adoption of different strategies to increase the pool of donors, such as ABO incompatible (ABOi) living KT. In this single center study, we retrospectively evaluated all donor/recipient pairs proposed for ABOi KT since the beginning of this transplantation program in our hospital in 2014. Methods: Between November 2014 and March 2022, 609 deceased donor and 223 living donor KT were performed in our center. Seventy-one donor/recipient pairs were proposed for ABOi KT and were evaluated for ABO/Rh group, Coombs tests, human leukocyte antigen (HLA) type I (A, B, C) and II (DR) high resolution genotyping and receptor to donor isoagglutinin titers and HLA antibodies. Recipients with immunoglobulins G (IgG) and/or M (IgM) isoagglutinin titers > 1:512 and/or with HLA donor specific alloantibodies (DSAs) were excluded from the ABOi transplantation program. Isoagglutinins removal was performed recurring to therapeutic plasma exchange (TPE) and/or immunoadsorption techniques. Transplanted patients were evaluated for demographic data, diagnosis, relationship with donor, sessions of antibodies removal, pre- and post-KT isoagglutinin titers, graft function, transfusion support, significant complications and overall patient survival. Results: Eighteen patients (14 males and 4 females) were transplanted with an ABOi graft out of 71 ABOi studied pairs. Median baseline IgG and IgM isoagglutinin titers were 1:32 (min 1:2, max 1:256) and 1:8 (min 1:2, max 1:32), respectively. Fifteen patients (83.3%) had pre-KT TPE and/or immunoadsorption sessions for isoagglutinin removal (mean 2.4 ± 1.8 session per patient). Seven patients (36.8%) were submitted to post-KT TPE (mean 1.9 ± 3.2 session per patient). No acute antibody mediated rejection was observed and overall graft survival was 100% on a follow-up period between 3 and 92 months (47.6 ± 25.2 months). All patients were dialysis-free with serum creatinine steady levels (median 1.4 mg/dL) at 47.6 ± 25.2 months of follow up. Conclusion: These results confirm that ABOi KT is a viable treatment for patients with ESRD, thus expanding living donor pool and reducing access time to transplantation.

Introdução: O transplante renal (TR) é o tratamento de eleição dos doentes com doença renal terminal. A escassez de órgãos continua a ser uma limitação importante, dado o número crescente de doentes a aguardar transplante, levando à adoção de diferentes estratégias para aumentar o número de doadores, tal como o TR ABO incompatível (ABOi) de doador vivo. Neste estudo unicêntrico, avaliamos retrospectivamente todos os pares doador/receptor propostos para TR ABOi desde a implementação do programa de transplante no nosso hospital em 2014. Métodos: Entre novembro de 2014 e março de 2022, foram realizados 609 TR de doador cadáver e 223 TR de doador vivo. Setenta e um pares doador/receptor foram propostos para TR ABOi e avaliados para grupo ABO/Rh, teste de Coombs, genotipagem de alta resolução de antígeno leucocitário humano (HLA) tipo I (A, B, C) e II (DR), titulação de isoaglutininas receptor/doador e anticorpos HLA. Receptores com títulos de isoaglutininas da classe G (IgG) e/ou M (IgM) > 1:512 e/ou aloanticorpos HLA doador específicos (DSAs) foram excluídos do programa de transplante ABOi. A remoção das isoaglutininas foi realizada através de técnicas de troca plasmática terapêutica (TPT) e/ou imunoadsorção. Os doentes transplantados foram avaliados quanto a dados demográficos, diagnóstico, relação com o doador, sessões de remoção de anticorpos, títulos de isoaglutininas pré- e pós-TR, viabilidade do enxerto, suporte transfusional, complicações significativas e sobrevida global do doente. Resultados: Dezoito doentes (14 homens e 4 mulheres) foram transplantados com enxerto ABOi dos 71 pares ABOi estudados. A mediana dos títulos de isoaglutininas IgG e IgM foram 1:32 (min. 1:2, máx. 1:256) e 1:8 (min. 1:2, máx. 1:32), respetivamente. Quinze pacientes (83.3%) foram submetidos a sessões de TPT e/ou imunoadsorção pré-TR para remoção de isoaglutininas (média 2.4 ± 1.8 sessões por doente). Sete doentes (36.8%) foram submetidos a TPT pós-TR (média 1.9 ± 3.2 sessões por doente). Não foi observada rejeição aguda mediada por anticorpos e a sobrevida global do enxerto foi de 100% num período de seguimento entre 3 e 92 meses (47.6 ± 25.2 meses). Todos os doentes estavam livres de diálise com níveis estáveis de creatinina sérica (mediana 1.4 mg/dL) em 47.6 ± 25.2 meses de seguimento. Conclusão: Estes resultados confirmam que o TR ABOi é um tratamento viável para doentes com doença renal terminal, expandindo assim o número de doadores vivos e reduzindo o tempo de espera para transplante.

Optical gas sensors have emerged as an alternative to conventional conductometric sensors, opening new possibilities, especially for the detection of polluting and/or toxic molecules, such as carbon monoxide (CO). In this letter, an optimized plasmonic thin film, composed of Au nanoparticles embedded in a CuO matrix, was tested as a CO sensor, using high-resolution localized surface plasmon resonance (LSPR) spectroscopy. The Au:CuO thin film system was found to be highly sensitive, exhibiting a fast (∼14 s) and reversible (∼50 s) response when exposed to 50 ppm of CO, working at room temperature. Furthermore, the Au:CuO thin film prototype sensor presented a signal-to-noise ratio of 11, calculated at the transmittance minimum of the LSPR band, which allowed estimation of a detection limit as low as 14 ppm for CO gas.

Gas sensing based on bulk refractive index (RI) changes, has been a challenging task for localized surface plasmon resonance (LSPR) spectroscopy, presenting only a limited number of reports in this field. In this work, it is demonstrated that a plasmonic thin film composed of Au nanoparticles embedded in a CuO matrix can be used to detect small changes (as low as 6 × 10-5 RIU) in bulk RI of gases at room temperature, using a high-resolution LSPR spectroscopy system. To optimize the film's surface, a simple Ar plasma treatment revealed to be enough to remove the top layers of the film and to partially expose the embedded nanoparticles, and thus enhance the film's gas sensing capabilities. The treated sample exhibits high sensitivity to inert gases (Ar, N2), presenting a refractive index sensitivity (RIS) to bulk RI changes of 425 nm/RIU. Furthermore, a 2-fold signal increase is observed for O2, showing that the film is clearly more sensitive to this gas due to its oxidizing nature. The results showed that the Au:CuO thin film system is a RI sensitive platform able to detect inert gases, which can be more sensitive to detect noninert gases as O2 or even other reactive species.

In this observational study performed during 45 months we evaluated patients with chronic and recalcitrant diabetic ulcers who were treated with homologous platelet gel. Methods platelet gels were obtained from homologous platelet concentrates that were aliquoted and freezed, being then activated with calcium gluconate and applied in the ulcer after cleaning and debridement. We evaluated patient's comorbidities, wound characteristics (size, tissue, inflammatory signs, pain), number and time of treatment as well as outcome (classified as complete epithelialization; partial improvement- 50% reduction in wound size or pain relief; no evolution). Results Fifty-two patients (42 males, 10 females), with a median age of 65 years (range 43–85) were proposed for platelet gel. The following associated comorbidities were observed: hypertension (n = 41), dyslipidemia (n = 29), polyneuropathy (n = 30), peripheral arteriopathy (n = 32), retinopathy (n = 21), nephropathy (n = 15), cardiac ischemic disease (n = 14), obesity (n = 9). Thirty-eight patients presented with 3 or more associated comorbidities. The more frequent ulcer locations were sole of the foot (n = 13) and heel (n = 10). The median number of applications was 16, during 8.5 weeks. Nineteen patients (44%) achieved complete healing, 3 patients (7%) had a partial response and 21 (49%) had no progression. We did not observe a statistically significant relationship between patient age and response nor between number of comorbidities and response. We observed a more favorable evolution in patients with good compliance and good glycemic control. Conclusion Platelet gel is an effective therapeutic alternative, provided compliance and effective metabolic control are ensured.

BackgroundRare pathogenic variants in either theITGA2BorITGB3genes have been linked to autosomal dominant macrothrombocytopenia associated with abnormal platelet production and function, deserving the designation of Glanzmann Thrombasthenia-Like Syndrome (GTLS) or ITGA2B/ITGB3-related thrombocytopenia.ObjectivesTo describe a series of patients with familial macrothrombocytopenia and decreased expression of αIIbβ3 integrin due to defects in theITGA2BorITGB3genes.MethodsWe reviewed the clinical and laboratory records of 10 Portuguese families with GTLS (33 patients and 11 unaffected relatives), including the functional and genetic defects.ResultsPatients had absent to moderate bleeding, macrothrombocytopenia, low αIIbβ3 expression, impaired platelet aggregation/ATP release to physiological agonists and low expression of activation-induced binding sites on αIIbβ3 (PAC-1) and receptor-induced binding sites on its ligand (bound fibrinogen), upon stimulation with TRAP-6 and ADP. Evidence for constitutive αIIbβ3 activation, occurred in 2 out of 9 patients from 8 families studied, but also in 2 out of 12 healthy controls. We identified 7 missense variants: 3 inITGA2B(5 families), and 4 inITGB3(5 families). Three variants (αIIb: p.Arg1026Trp and p.Arg1026Gln and β3: p.Asp749His) were previously reported. The remaining (αIIb: p.Gly1007Val and β3: p.Thr746Pro, p.His748Pro and p.Arg760Cys) are new, expanding the αIIbβ3 defects associated with GTLS. The integration of the clinical and laboratory data allowed the identification of two GTLS subgroups, with distinct disease severity.ConclusionsPreviously reportedITGA2BandITGB3variants related to thrombocytopenia were clustered in a confined region of the membrane-proximal cytoplasmic domains, the inner membrane clasp. For the first time, variants are reported at the outer membrane clasp, at the transmembrane domain of αIIb, and at the membrane distal cytoplasmic domains of β3. This is the largest single-center series of inherited macrothrombocytopenia associated with αIIbβ3 variants published to date.

Ti1−xCux thin films were produced by the glancing angle deposition technique (GLAD) for resistance temperature measurements. The deposition angle was fixed at α = 0° to growth columnar structures and α = 45° to growth zigzag structures. The Ti-to-Cu atomic concentration was tuned from 0 to 100 at.% of Cu in order to optimize the temperature coefficient of resistance (TCR) value. Increasing the amount of Cu in the Ti1−xCux thin films, the electrical conductivity was gradually changed from 4.35 to 7.87 × 105 Ω−1 m−1. After thermal “stabilization,” the zigzag structures of Ti1−xCux films induce strong variation of the thermosensitive response of the materials and exhibited a reversible resistivity versus temperature between 35 and 200 °C. The results reveal that the microstructure has an evident influence on the overall response of the films, leading to values of TCR of 8.73 × 10−3 °C−1 for pure copper films and of 4.38 × 10−3 °C−1 for a films of composition Ti0.49Cu0.51. These values are very close to the ones reported for the bulk platinum (3.93 × 10−3 °C−1), which is known to be one of the best material available for these kind of temperature-related applications. The non-existence of hysteresis in the electrical response of consecutive heating and cooling steps indicates the viability of these nanostructured zigzag materials to be used as thermosensitive sensors., Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013 and Project PTDC/EEI-SII/5582/2014. A. Ferreira and C. Lopes thanks the FCT for Grant SFRH/BPD/102402/2014 and SFRH/BD/103373/2014. The authors thank financial support from the Basque Government Industry Department under the ELKARTEK Program, info:eu-repo/semantics/publishedVersion

International audience; Nanocomposite thin films, composed of monometallic Au and Ag, and bimetallic AuAg nanoparticles, dispersed in a CuO matrix were prepared, characterised and tested for Localized Surface Plasmon Resonance (LSPR) sensing. The films were deposited by reactive magnetron sputtering, followed by a post-deposition thermal annealing to modify the size and shape of the nanoparticles distribution within the oxide matrix. Regarding the main results of the monometallic systems, the Au:CuO films showed LSPR bands from 800 nm to 650 nm, which reveal a progressive narrowing and a continuous blue-shift with increasing temperature (400–700 °C). The Ag:CuO films evidenced plasmonic bands at about 400 nm for temperatures of 500 °C and above. The bimetallic system, Au-Ag:CuO, showed LSPR bands in the range between those of the corresponding monometallic systems, due to the presence of Ag enriched AuAg alloy nanoparticles, taking part of Janus-like structures in some cases. In terms of LSPR sensing, Au:CuO films revealed the highest values of refractive index sensitivity since the nanoparticles are more exposed to the surrounding environment.

International audience; AbstractIn this work, a versatile method is proposed to increase the sensitivity of optical sensors based on the localized surface plasmon resonance (LSPR) phenomenon. It combines a physical deposition method with the oblique angle deposition technique, allowing the preparation of plasmonic thin films with tailored porosity. Thin films of Au–TiO2 were deposited by reactive magnetron sputtering in a 3D nanostructure (zigzag growth), at different incidence angles (0°„α„80°), followed by in-air thermal annealing at 400°C to induce the growth of the Au nanoparticles. The roughness and surface porosity suffered a gradual increment by increasing the incidence angle. The resulting porous zigzag nanostructures that were obtained also decreased the principal refractive indexes (RIs) of the matrix and favoured the diffusion of Au through grain boundaries, originating broader nanoparticle size distributions. The transmittance minimum of the LSPR band appeared at around 600nm, leading to a red-shift to about 626nm for the highest incidence angle α=80°, due to the presence of larger (scattering) nanoparticles. It is demonstrated that zigzag nanostructures can enhance adsorption sites for LSPR sensing by tailoring the porosity of the thin films. Atmosphere controlled transmittance-LSPR measurements showed that the RI sensitivity of the films is improved for higher incidence angles.

International audience; Plasmonic Au nanoparticles (AuNPs) embedded into a TiO2 dielectric matrix were analyzed by combining two-dimensional and three-dimensional electron microscopy techniques. The preparation method was reactive magnetron sputtering, followed by thermal annealing treatments at 400 and 600 °C. The goal was to assess the nanostructural characteristics and correlate them with the optical properties of the AuNPs, particularly the localized surface plasmon resonance (LSPR) behavior. High-angle annular dark fieldscanning transmission electron microscopy results showed the presence of small-sized AuNPs (quantum size regime) in the as-deposited Au−TiO2 film, resulting in a negligible LSPR response. The in-vacuum thermal annealing at 400 °C induced the formation of intermediate-sized nanoparticles (NPs), in the range of 10−40 nm, which led to the appearance of a well-defined LSPR band, positioned at 636 nm. Electron tomography revealed that most of the NPs are small-sized and are embedded into the TiO2 matrix, whereas the larger NPs are located at the surface. Annealing at 600 °C promotes a bimodal size distribution with intermediate-sized NPs embedded in the matrix and bigsized NPs, up to 100 nm, appearing at the surface. The latter are responsible for a broadening and a redshift, to 645 nm, in the LSPR band because of increase of scattering-to-absorption ratio. Beyond differentiating and quantifying the surface and embedded NPs, electron tomography also provided the identification of “hot-spots”. The presence of NPs at the surface, individual or in dimers, permits adsorption sites for LSPR sensing and for surface-enhanced spectroscopies, such as surfaceenhanced Raman scattering.

International audience; In the present work, Agy:TiNx thin films,obtained by reactive DC magnetron sputtering, withdecreasing [N]/[Ti] atomic ratios (from 1 to 0.1) and afixed amount of Ag pellets placed in the erosion zone of apure Ti target, were studied envisaging their application asbiopotential electrodes. The strongly under-stoichiometricsamples, [N]/[Ti] = 0.1 and 10 at.% Ag; [N]/[Ti] = 0.2and 8 at.% Ag, were found to be composed of a N-dopedhcp-Ti structure, with possible formation of TiAg or Ti2Agintermetallics. These samples exhibit high electrical resistivityvalues and low hardness and reduced modulus. In theset of samples indexed to a transition zone, [N]/[Ti] = 0.3and 15 at.% Ag; [N]/[Ti] = 0.7 and 32 at.% Ag, a hcp-Tito fcc-TiN phase transformation took place, giving rise to adisaggregated N-deficient TiN matrix. It correlates with thehigh resistivity values as well as the higher hardness andreduced modulus values that were obtained. The lastidentified zone comprised the stoichiometric Ag:TiNxsample—[N]/[Ti] = 1 and 20 at.% Ag. Extensive metallicAg segregation was detected, contributing to a significantdecrease of the resistivity and hardness values.

We present a pedagogical introduction to the problem of evolving a head on collision of two Aichelburg-Sexl gravitational shock waves in D-dimensions, using perturbative techniques. We follow a constructive approach with examples, going in some detail through: the set up of the exact initial conditions and their properties; perturbative methods in flat space-time with Green function solutions; and numerical strategies to evaluate the integral solutions. We also discuss, briefly, radiation extraction methods adapted to this problem, together with some of the results for this system., Comment: Lecture notes from the NRHEP spring school held at IST-Lisbon, March 2013. Extra material and notebooks available online at http://blackholes.ist.utl.pt/nrhep2/ To be published by IJMPA (V. Cardoso, L. Gualtieri, C. Herdeiro and U. Sperhake, Eds., 2013)