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Boulton S, Crupi MJF, Singh S, Carter-Timofte ME, Azad T, Organ BC, He X, Gill R, Neault S, Jamieson T, Dave J, Kurmasheva N, Austin B, Petryk J, Singaravelu R, Huang BZ, Franco N, Babu K, Parks RJ, Ilkow CS, Olagnier D, Bell JC. Inhibition of Exchange Proteins Directly Activated by cAMP (EPAC) as a Strategy for Broad-Spectrum Antiviral Development. J Biol Chem 2023; 299:104749. [PMID: 37100284 PMCID: PMC10124099 DOI: 10.1016/j.jbc.2023.104749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 04/17/2023] [Accepted: 04/18/2023] [Indexed: 04/28/2023] Open
Abstract
The recent SARS-CoV-2 and mpox outbreaks have highlighted the need to expand our arsenal of broad-spectrum antiviral agents for future pandemic preparedness. Host-directed antivirals are an important tool to accomplish this as they typically offer protection against a broader range of viruses than direct-acting antivirals and have a lower susceptibility to viral mutations that cause drug resistance. In this study, we investigate the Exchange Protein Activated by cAMP (EPAC) as a target for broad-spectrum antiviral therapy. We find that the EPAC-selective inhibitor, ESI-09 provides robust protection against a variety of viruses, including SARS-CoV-2 and Vaccinia (VACV) - an orthopoxvirus from the same family as mpox. We show, using a series of immunofluorescence experiments, that ESI-09 remodels the actin cytoskeleton through Rac1/Cdc42 GTPases and the Arp2/3 complex, impairing internalization of viruses that use clathrin-mediated endocytosis (e.g. VSV) or micropinocytosis (e.g. VACV). Additionally, we find that ESI-09 disrupts syncytia formation and inhibits cell-to-cell transmission of viruses such as measles and VACV. When administered to immune-deficient mice in an intranasal challenge model, ESI-09 protects mice from lethal doses of VACV and prevents formation of pox lesions. Altogether, our finding show that EPAC antagonists such as ESI-09 are promising candidates for broad-spectrum antiviral therapy that can aid in the fight against ongoing and future viral outbreaks.
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Mosquera-Guerra F, Trujillo F, Oliveira-da-Costa M, Marmontel M, Van Damme PA, Franco N, Córdova L, Campbell E, Alfaro-Shigueto J, Mena JL, Mangel JC, Oviedo JSU, Carvajal-Castro JD, Mantilla-Meluk H, Armenteras-Pascual D. Home range and movements of Amazon river dolphins Inia geoffrensis in the Amazon and Orinoco river basins. ENDANGER SPECIES RES 2021. [DOI: 10.3354/esr01133] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Studying the variables that describe the spatial ecology of threatened species allows us to identify and prioritize areas that are critical for species conservation. To estimate the home range and core area of the Endangered (EN) Amazon river dolphin Inia geoffrensis, 23 individuals (6♀, 17♂) were tagged during the rising water period in the Amazon and Orinoco river basins between 2017 and 2018. The satellite tracking period ranged from 24 to 336 d (mean ± SE = 107 ± 15.7 d), and river dolphin movements ranged from 7.5 to 298 km (58 ± 13.4 km). Kernel density estimates were used to determine minimum home ranges at 95% (K95 = 6.2 to 233.9 km2; mean = 59 ± 13.5 km2) and core areas at 50% (K50 = 0.6 to 54.9 km2; mean = 9 ± 2.6 km2). Protected areas accounted for 45% of the K50 estimated core area. We observed dolphin individuals crossing country borders between Colombia and Peru in the Amazon basin, and between Colombia and Venezuela in the Orinoco basin. Satellite tracking allowed us to determine the different uses of riverine habitat types: main rivers (channels and bays, 52% of recorded locations), confluences (32%), lagoons (9.6%), and tributaries (6.2%). Satellite monitoring allowed us to better understand the ecological preferences of the species and demonstrated the importance of maintaining aquatic landscape heterogeneity and spatial connectivity for effective river dolphin conservation.
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Valente F, Franco N, Rosa M, Degregori E, Lhamas C, Andrades A, Vidor S, Santos A, Kommers G, Graça D, Müller D, Contesini E. Células-tronco mesenquimais de origem adiposa na fase de proliferação do processo de cicatrização de queimaduras frias. ARQ BRAS MED VET ZOO 2020. [DOI: 10.1590/1678-4162-10855] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
RESUMO A criocirurgia tem sido utilizada no tratamento de diferentes enfermidades de sistemas e órgãos. Contudo, são relatados efeitos adversos, como cicatrização lenta, cicatrizes extensas, disfunção estética e funcional. As lesões que ocorrem naturalmente pela exposição ao frio extremo, comumente, resultam em gangrena. O presente trabalho teve como objetivo avaliar a influência das células-tronco mesenquimais de origem adiposa (ADSCs) na fase de proliferação da cicatrização de feridas cutâneas. Por meio da aplicação do nitrogênio líquido pela técnica do spray aberto, realizou-se a indução de uma ferida, de aproximadamente 15mm de diâmetro, na região dorsal de cada rato. A ferida recebeu o tratamento de acordo com o grupo ao qual pertencia: 1) aplicação das ADSCs no 15º dia (grupo tratado); 2) aplicação da solução cloreto de sódio 0,9% no 15º dia (grupo sham); 3) nenhuma intervenção até o momento da eutanásia (grupo controle). O grupo tratado com as ADSCs apresentou as maiores taxas de contração média das feridas e obteve diferença estatisticamente significativa em relação ao grupo sham quanto à neovascularização. A terapia com as ADSCs proporcionou uma relevante evolução clínica das feridas, podendo ser constatada ao final do período de avaliação por cicatrizes mais estreitas e compridas.
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Mosquera-Guerra F, Trujillo F, Parks D, Oliveira-da-Costa M, Van Damme PA, Echeverría A, Franco N, Carvajal-Castro JD, Mantilla-Meluk H, Marmontel M, Armenteras-Pascual D. Mercury in Populations of River Dolphins of the Amazon and Orinoco Basins. ECOHEALTH 2019; 16:743-758. [PMID: 31712931 DOI: 10.1007/s10393-019-01451-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Accepted: 10/03/2019] [Indexed: 05/26/2023]
Abstract
In the Amazon and Orinoco basins, mercury has been released from artisanal and industrial gold mining since the Colonial time, as well as a result of deforestation and burning of primary forest, that release natural deposits of methyl mercury, affecting the local aquatic vertebrate fauna. This study reports the presence of mercury in river dolphins' genera Inia and Sotalia. Mercury concentrations were analysed in muscle tissue samples collected from 46 individuals at the Arauca and Orinoco Rivers (Colombia), the Amazon River (Colombia), a tributary of the Itenez River (Bolivia) and from the Tapajos River (Brazil). Ranges of total mercury (Hg) concentration in muscle tissue of the four different taxa sampled were: I. geoffrensis humboldtiana 0.003-3.99 mg kg-1 ww (n = 21, Me = 0.4), I. g. geoffrensis 0.1-2.6 mg kg-1 ww (n = 15, Me = 0.55), I. boliviensis 0.03-0.4 mg kg-1 ww (n = 8, Me = 0.1) and S. fluviatilis 0.1-0.87 mg kg-1 ww (n = 2, Me = 0.5). The highest Hg concentration in our study was obtained at the Orinoco basin, recorded from a juvenile male of I. g. humboldtiana (3.99 mg kg-1 ww). At the Amazon basin, higher concentrations of mercury were recorded in the Tapajos River (Brazil) from an adult male of I. g. geoffrensis (2.6 mg kg-1 ww) and the Amazon River from an adult female of S. fluviatilis (0.87 mg kg-1 ww). Our data support the presence of total Hg in river dolphins distributed across the evaluated basins, evidencing the role of these cetaceans as sentinel species and bioindicators of the presence of this heavy metal in natural aquatic environments.
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Martins IEB, Onofre S, Franco N, Martins LM, Montenegro A, Arana-Gordillo LA, Reis A, Loguercio AD, da Silva LM. Effectiveness of In-office Hydrogen Peroxide With Two Different Protocols: A Two-center Randomized Clinical Trial. Oper Dent 2018; 43:353-361. [DOI: 10.2341/17-128-c] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
SUMMARY
Objectives:
The aim of this study was to compare the bleaching efficacy and tooth sensitivity (TS) of a 38% hydrogen peroxide bleaching agent used for in-office bleaching, applied under different time protocols: a 40-minute application or two 20-minute applications.
Methods and Materials:
Forty-four patients from Brazil and Colombia, with right superior canines darker than C2, were selected for this multicenter, single-blind, randomized trial. The teeth were bleached in two sessions, with a one-week interval between them, in a split-mouth design. The bleaching agent was applied in two 20-minute (2×20) applications or one 40-minute (1×40) application in each session according to the manufacturer's instructions. The color changes were evaluated by using subjective (Vita Classical and Vita Bleachedguide) and objective (Easyshade Spectrophotometer) methods at baseline and 30 days after the second session. Tooth sensitivity was recorded up to 48 hours with a 0-10 visual analog scale. Also, the pH values during the application of bleaching were recorded. Color change in shade guide units and ΔE were analyzed by using the Student t-test (α=0.05). The absolute risk and intensity of TS were evaluated with the McNemar test, the Wilcoxon signed-rank test, and the Friedman test, respectively (α= 0.05).
Results:
Significant whitening was observed in both groups after 30 days of clinical evaluation. The use of a 40-minute application did not significantly influence the absolute risk of TS (68%, 95% confidence interval [CI] = 53-80) as well as the intensity of TS compared with the acid bleaching gel (absolute risk of 82%, 95% CI = 68-91). The pH values did not differ significantly between groups and at the different assessment periods (p=0.42).
Conclusion:
The use of a 40-minute in-office bleaching agent gel application produced the same whitening degree and TS that the two 20-minute bleaching agent applications did. The former preferably should be applied because one 40-minute application does not require gel refreshing.
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Alves E, Alves LC, Franco N, Da Silva MR, Paúl A. Structural and Oxidation Studies of Titanium Beryllides. NUCL TECHNOL 2017. [DOI: 10.13182/nt07-a3870] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Mateus R, Franco N, Alves E. Retention behaviour of deuterium and helium in beryllium under single D+ and dual He+/D+ exposure. FUSION ENGINEERING AND DESIGN 2015. [DOI: 10.1016/j.fusengdes.2015.06.127] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Castellanos-Ortega A, Rothen HU, Franco N, Rayo LA, Martín-Loeches I, Ramírez P, Cuñat de la Hoz J. Training in intensive care medicine. A challenge within reach. Med Intensiva 2014; 38:305-10. [PMID: 24589154 DOI: 10.1016/j.medin.2013.12.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 12/30/2013] [Indexed: 11/30/2022]
Abstract
The medical training model is currently immersed in a process of change. The new paradigm is intended to be more effective, more integrated within the healthcare system, and strongly oriented towards the direct application of knowledge to clinical practice. Compared with the established training system based on certification of the completion of a series or rotations and stays in certain healthcare units, the new model proposes a more structured training process based on the gradual acquisition of specific competences, in which residents must play an active role in designing their own training program. Training based on competences guarantees more transparent, updated and homogeneous learning of objective quality, and which can be homologated internationally. The tutors play a key role as the main directors of the process, and institutional commitment to their work is crucial. In this context, tutors should receive time and specific formation to allow the evaluation of training as the cornerstone of the new model. New forms of objective summative and training evaluation should be introduced to guarantee that the predefined competences and skills are effectively acquired. The free movement of specialists within Europe is very desirable and implies that training quality must be high and amenable to homologation among the different countries. The Competency Based training in Intensive Care Medicine in Europe program is our main reference for achieving this goal. Scientific societies in turn must impulse and facilitate all those initiatives destined to improve healthcare quality and therefore specialist training. They have the mission of designing strategies and processes that favor training, accreditation and advisory activities with the government authorities.
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Grosseto D, Carigi S, Santarelli A, Baldazzi F, Franco N, Amati S, Santoro D, Marinelli L, Marconi M, Piovaccari G. Takotsubo cardiomiopathy: incidence, clinical features and prognosis in all comers patients referred for acute coronary syndrome. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht307.p461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Dy CJ, Franco N, Ma Y, Mazumdar M, McCarthy MM, Gonzalez Della Valle A. Complications after patello-femoral versus total knee replacement in the treatment of isolated patello-femoral osteoarthritis. A meta-analysis. Knee Surg Sports Traumatol Arthrosc 2012; 20:2174-90. [PMID: 21987361 DOI: 10.1007/s00167-011-1677-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Accepted: 09/12/2011] [Indexed: 12/18/2022]
Abstract
PURPOSE Both patellofemoral arthroplasty (PFA) and total knee arthroplasty (TKA) are successful in treating isolated patellofemoral osteoarthritis, but the complication rates after PFA are concerning. We performed a meta-analysis to compare the incidence of complications, re-operations, and revision following PFA and TKA for patellofemoral osteoarthritis. METHODS We systematically identified publications with patients who underwent PFA or TKA for patellofemoral osteoarthritis with minimum 1.5 year follow-up. Demographics, implant (TKA, first [1G] or second-generation [2G] PFA), complications, and cause of re-operations were extracted. Random-effects meta-analysis was used to pool incidence data, which was compared between groups using logistic regression to adjust for length of follow-up. RESULTS Twenty-eight observational studies and no randomized trials were included in this meta-analysis, which limits its generalizability. There was a higher likelihood of any re-operation (odds ratio 8.06) and revision (OR 8.11) in PFA compared to TKA. Re-operation (OR 4.33) and revision (OR 4.93) were more likely in 1G-PFA than 2G-PFA. When comparing 2G-PFA to TKA, there was no significant difference in re-operation, revision, pain, or mechanical complications. CONCLUSIONS Patients who undergo PFA rather than TKA are more likely to experience complications and require re-operation or revision, but subgroup analysis suggests a relation to implant design. There is no significant difference in re-operation, revision, pain, or mechanical complications between 2G-PFA and TKA. LEVEL OF EVIDENCE Systematic review of Level III therapeutic studies, Level III.
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Cortellini G, Testi S, Severino M, Chechi T, Iorno ML, Santucci A, Corvetta A, Piovaccari G, Santarelli A, Franco N, Canonica GW, Passalacqua G. Aspirin challenge/desensitisation before coronary stenting in subjects with history of hypersensitivity. A pragmatic approach. Eur Ann Allergy Clin Immunol 2012; 44:160-162. [PMID: 23092002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
BACKGROUND Aspirin hypersensitivity may represent a major problem in patients with ischemic coronary disease who need a stenting procedure. In those patients, clinically unsettled reasonably quick desensitisation procedures are needed. In our study we attempted to select the most suitable procedure on the basis of characteristics and severity of ASA hypersensitivity. METHODS Thirty patients with a history of mild reactions to anti-inflammatory doses of aspirin (> 325 mg) were considered at low risk and underwent a tolerance test in 5 steps. Thirty-one patients, with a history of severe reactions to anti-platelet doses of aspirin 0 mg) underwent a slow desensitisation in 12 steps, reaching a cumulative dose of 150 mg ASA in 220 minutes. RESULTS In the first group, 29 patients tolerated the challenge. One developed urticaria, thus underwent challenge/desensitisation and achieved tolerance. In the second group, 3 patients did not tolerate the procedure and had to discontinue. CONCLUSION. Our approach to aspirin hypersensitivity in patients needing coronary stenting, based on a severity stratification, allowed to achieve an effective tolerance to aspirin in the majority of subject in a reasonable short time.
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Redondo-Cubero A, Hierro A, Chauveau JM, Lorenz K, Tabares G, Franco N, Alves E, Muñoz E. Single phase a-plane MgZnO epilayers for UV optoelectronics: substitutional behaviour of Mg at large contents. CrystEngComm 2012. [DOI: 10.1039/c2ce06315h] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kurinskiy P, Chakin V, Moeslang A, Rolli R, Alves E, Alves L, Franco N, Dorn C, Goraieb A. Comparative study of fusion relevant properties of Be12V and Be12Ti. FUSION ENGINEERING AND DESIGN 2011. [DOI: 10.1016/j.fusengdes.2010.12.065] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Vecchio S, Zanolla L, Valencia J, Colletta M, Capecchi A, Franco N, Piovaccari G, Margheri M, Di Pasquale G, Rubboli A. Coronary stenting for ST-elevation myocardial infarction vs. other indications in patients on oral anticoagulation: any difference in in-hospital management and outcome? Minerva Cardioangiol 2011; 59:499-506. [PMID: 21983310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
AIM The aim of this paper was to compare the in-hospital management and outcome of patients on oral anticoagulation (OAC) undergoing coronary artery stenting (PCI-S) for ST-elevation myocardial infarction (STEMI) vs. other indications. METHODS One hundred and sixteen patients on OAC at the time of PCI-S who were prospectively enrolled in a multi-center, observational registry, were evaluated. Patients were segregated according to whether PCI-S was performed for STEMI (group 1) or other indications, such as non ST-elevation acute coronary syndromes, stable angina, silent ischemia, etc. (group 2), and the pharmacological and procedural management, as well as the in-hospital outcome, were compared. RESULTS No significant differences were observed in vascular access site, sheath size and type of stent implanted, nor was significantly different the use of glycoprotein IIb/IIIa inhibitors, and the use and dose of intravenous unfractionated heparin. Although not statistically different, the in-hospital occurrence of death (3.7% vs. 1.1%; OR 3.3; 95% confidence intervals [CI] 0.2-56.0), stent thrombosis (3.7% vs. 1.1%; OR 3.3; 95% CI 0.2-56.0) and major bleeding (7.4% vs. 2.2%; OR 3.4; 95% CI 0.4-25.9) was consistently about 3-fold higher in group 1. CONCLUSION The in-hospital pharmacological and procedural management of OAC patients undergoing PCI-S for STEMI vs. other indications appears not different. Although not significantly different however, the in-hospital occurrence of major bleeding, as well as of death and stent thrombosis, appears substantially higher in patients treated for STEMI, warranting therefore further larger, prospective studies.
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Mateus R, Carvalho P, Nunes D, Alves L, Franco N, Correia J, Alves E. Microstructural characterization of the ODS Eurofer 97 EU-batch. FUSION ENGINEERING AND DESIGN 2011. [DOI: 10.1016/j.fusengdes.2011.01.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Magalhães S, Lorenz K, Franco N, Barradas NP, Alves E, Monteiro T, Amstatt B, Fellmann V, Daudin B. Effect of annealing on AlN/GaN quantum dot heterostructures: advanced ion beam characterization and X-ray study of low-dimensional structures. SURF INTERFACE ANAL 2010. [DOI: 10.1002/sia.3614] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Peixoto RS, Chaer GM, Franco N, Reis Junior FB, Mendes IC, Rosado AS. A decade of land use contributes to changes in the chemistry, biochemistry and bacterial community structures of soils in the Cerrado. Antonie van Leeuwenhoek 2010; 98:403-13. [PMID: 20495870 DOI: 10.1007/s10482-010-9454-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 05/05/2010] [Indexed: 11/24/2022]
Abstract
The bacterial community structures (BCSs) of Cerrado soils cultivated under conventional tillage (CT), no-tillage (NT) and under native Cerrado (NC) vegetation were evaluated using PCR/DGGE of bacterial 16S rRNA (rrs) and rpoB genes and of Pseudomonas group genes. Soil chemical analysis, microbial biomass and the enzyme activities were also evaluated and correlated with the BCS measurements. The multivariate ordinations of DGGE profiles showed differences between the BCS of the NC area and those from cultivated areas. The BCSs of the CT and NT areas also differed in all DGGE fingerprints, including changes in the profile of Pseudomonas populations, indicating that agricultural systems can also be responsible for changes within specific microbial niches, although the clearest differences were found in the rpoB profiles. The MRPP analysis demonstrated significant differences between the BCSs from different soil layers of NT areas based on all gene fingerprints and those of NC areas based on bacterial 16S rRNA and rpoB genes fingerprints. No differences were observed in the microbial fingerprints of CT samples from different depths, indicating that ploughing affected the original BCS stratification. The BCS from NC areas, based on all gene fingerprints, could be related to higher levels of soil acidity and higher amounts of MBC and of phosphatase activity. In contrast, the BCSs from cultivated areas were related to higher levels of Ca + Mg, P and K, likely as a result of a history of chemical fertilisation in these areas. The relationships between rpoB and Pseudomonas BCSs and all chemical and biochemical properties of soils were significant, according to a Mantel test (P < 0.05), indicating that the different changes in soil properties induced by soil use or management may drive the formation of the soil BCS.
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Peres M, Neves AJ, Monteiro T, Magalhães S, Franco N, Lorenz K, Alves E, Damilano B, Massies J, Dussaigne A, Grandjean N. Optical and structural properties of an Eu implanted gallium nitride quantum dots/aluminium nitride superlattice. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:2473-2478. [PMID: 20355450 DOI: 10.1166/jnn.2010.1430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
GaN/AIN structures made of GaN quantum dots (QDs) separated by AIN spacer layers, were doped with Europium by ion implantation. Rutherford Backscattering/Channelling measurements showed that Eu is incorporated mainly on near-substitutional cation sites within the superlattice region. Only slight deterioration of the crystal quality and no intermixing of the different layers are observed after implantation and annealing. After thermal annealing, photoluminescence associated with Eu3+ ions was observed. From its behaviour under different photon energy excitation and sample temperature we concluded that the Eu-related emitting centres are located inside the GaN QDs or dispersed in the GaN and AIN buffer or spacer layers. The 624 nm PL line, associated with Eu-doped GaN QDs, shows very low thermal quenching, suggesting recombination of confined carriers through rare-earth ion excitation.
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Kurinskiy P, Chakin V, Moeslang A, Rolli R, Goraieb A, Harsch H, Alves E, Franco N. Characterisation of titanium beryllides with different microstructure. FUSION ENGINEERING AND DESIGN 2009. [DOI: 10.1016/j.fusengdes.2009.03.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Cruz MM, da Silva RC, Franco N, Godinho M. Ferromagnetism induced in rutile single crystals by argon and nitrogen implantation. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:206002. [PMID: 21825539 DOI: 10.1088/0953-8984/21/20/206002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The magnetic properties of Ar- and N-implanted single crystalline TiO(2) rutile were studied and correlated with the induced disorder in order to clarify the influence of defects in the magnetic behaviour. Nominal fluences of 1 × 10(17) and 2 × 10(17) cm(-2) and an implantation energy of 100 keV were used. The as-implanted single crystals exhibited ferromagnetic behaviour up to 380 K. Annealing at 1073 K induced recovery of the lattice structure and the decrease of the ferromagnetic moment in the case of Ar-implanted samples, but the magnetic moment did not change significantly for the samples implanted with nitrogen. No impurities, other than the implanted species were detected and consequently the ferromagnetic behaviour is attributed to defects created during implantation, which in the case of nitrogen remained in the lattice even after partial recovery of the structure.
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Marzocchi A, Manari A, Piovaccari G, Marrozzini C, Marra S, Magnavacchi P, Sangiorgio P, Marinucci L, Taglieri N, Gordini G, Binetti N, Guiducci V, Franco N, Reggiani MLB, Saia F. Randomized comparison between tirofiban and abciximab to promote complete ST-resolution in primary angioplasty: results of the facilitated angioplasty with tirofiban or abciximab (FATA) in ST-elevation myocardial infarction trial. Eur Heart J 2008; 29:2972-80. [DOI: 10.1093/eurheartj/ehn467] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Roig B, Virgos C, Franco N, Martorell L, Valero J, Costas J, Carracedo A, Labad A, Vilella E. The discoidin domain receptor 1 as a novel susceptibility gene for schizophrenia. Mol Psychiatry 2007; 12:833-41. [PMID: 17440435 DOI: 10.1038/sj.mp.4001995] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Evidence suggests that myelin alterations could predispose to schizophrenia. Reduced expression of several myelin genes has been observed in schizophrenia patients. Recently, we identified the discoidin domain receptor 1 (DDR1; located at human chromosome 6p21.3) as a myelin gene in the mouse model and in a human oligodendroglial cell line. In the present study we screened for single nucleotide polymorphisms (SNPs) in the DNA from 100 schizophrenia patients. We identified a novel mutation within exon 10 that produces the amino-acid substitution N502S in the a-d isoforms, and M475V in the e isoform. However the frequency of the mutation (2%) was similar in schizophrenia patients and in control subjects. In a case-control assessment with 389 schizophrenic patients and 615 controls, we identified one SNP (SNP9, rs1049623) associated with schizophrenia (odds ratio=1.44, 95% confidence interval: 1.15-1.79, adjusted P=0.0016). This association was confirmed in haplotype analysis; the SNPs 9-10-11 (rs1049623, rs2267641 and rs2239518) haplotype remaining significant even after adjustment for multiple testing (adjusted P=0.0136). Of note was a strong gender dependence in the association, that is, statistical significance restricted to men (adjusted P-value=0.0002). Regression analysis of DDR1 mRNA expression in peripheral blood lymphocytes from schizophrenia patients showed that the presence of the G allele significantly decreased the relative number of mRNA copies in a dose-dependent manner (P=0.003). These data suggest that the risk haplotype tags a cis-acting variant involved in the transcription regulation system of the gene. In conclusion, we propose the DDR1 as a new susceptibility gene for schizophrenia.
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Lorenz K, Franco N, Alves E, Watson IM, Martin RW, O'Donnell KP. Anomalous ion channeling in AlInN/GaN bilayers: determination of the strain state. PHYSICAL REVIEW LETTERS 2006; 97:085501. [PMID: 17026313 DOI: 10.1103/physrevlett.97.085501] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Indexed: 05/12/2023]
Abstract
Monte Carlo simulations of anomalous ion channeling in near-lattice-matched AlInN/GaN bilayers allow an accurate determination of the strain state of AlInN by Rutherford backscattering or channeling. Although these strain estimates agree well with x-ray diffraction (XRD) results, XRD composition estimates are shown to have limited accuracy, due to a possible deviation from Vegard's law, which we quantify for this alloy. As the InN fraction increases from 13% to 19%, the strain in AlInN films changes from tensile to compressive with lattice matching predicted to occur at [InN] = 17.1%.
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Alves E, Alves L, Franco N, da Silva M, Paúl A, Hegeman J, Druyts F. Characterization and stability studies of titanium beryllides. FUSION ENGINEERING AND DESIGN 2005. [DOI: 10.1016/j.fusengdes.2005.06.145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Izquierdo M, Dávila ME, Avila J, Ascolani H, Teodorescu CM, Martin MG, Franco N, Chrost J, Arranz A, Asensio MC. Epitaxy and magnetic properties of surfactant-mediated growth of bcc cobalt. PHYSICAL REVIEW LETTERS 2005; 94:187601. [PMID: 15904410 DOI: 10.1103/physrevlett.94.187601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2004] [Indexed: 05/02/2023]
Abstract
High resolution core level photoemission spectroscopy, photoelectron diffraction, and x-ray magnetic circular dicroism (XMCD) have been used to characterize the structural and magnetic properties of bcc-cobalt films grown on GaAs(110) substrates by using Sb as a surfactant. We have unambiguously disentangled the surfactant role played by the Sb which improves the crystallinity and reduces the lattice distortion of the metallic films as well as changes the interdiffusion process at the interface compared to the Co/GaAs(110) system. As a consequence of these combined effects, an improvement on the magnetic response of the grown Co thin films has been observed by XMCD measurements.
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