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1.
J Virol ; 96(3): e0114021, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-34851149

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) has evolved to escape the immune surveillance for a survival advantage leading to a strong modulation of host's immune responses and favoring secondary bacterial infections. However, limited data are available on how the immunological and transcriptional responses elicited by virulent and low-virulent PRRSV-1 strains are comparable and how they are conserved during the infection. To explore the kinetic transcriptional signature associated with the modulation of host immune response at lung level, a time-series transcriptomic analysis was performed in bronchoalveolar lavage cells upon experimental in vivo infection with two PRRSV-1 strains of different virulence, virulent subtype 3 Lena strain or the low-virulent subtype 1 3249 strain. The time-series analysis revealed overlapping patterns of dysregulated genes enriched in T-cell signaling pathways among both virulent and low-virulent strains, highlighting an upregulation of co-stimulatory and co-inhibitory immune checkpoints that were disclosed as Hub genes. On the other hand, virulent Lena infection induced an early and more marked "negative regulation of immune system process" with an overexpression of co-inhibitory receptors genes related to T-cell and NK cell functions, in association with more severe lung lesion, lung viral load, and BAL cell kinetics. These results underline a complex network of molecular mechanisms governing PRRSV-1 immunopathogenesis at lung level, revealing a pivotal role of co-inhibitory and co-stimulatory immune checkpoints in the pulmonary disease, which may have an impact on T-cell activation and related pathways. These immune checkpoints, together with the regulation of cytokine-signaling pathways, modulated in a virulence-dependent fashion, orchestrate an interplay among pro- and anti-inflammatory responses. IMPORTANCE Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the major threats to swine health and global production, causing substantial economic losses. We explore the mechanisms involved in the modulation of host immune response at lung level performing a time-series transcriptomic analysis upon experimental infection with two PRRSV-1 strains of different virulence. A complex network of molecular mechanisms was revealed to control the immunopathogenesis of PRRSV-1 infection, highlighting an interplay among pro- and anti-inflammatory responses as a potential mechanism to restrict inflammation-induced lung injury. Moreover, a pivotal role of co-inhibitory and co-stimulatory immune checkpoints was evidenced, which may lead to progressive dysfunction of T cells, impairing viral clearance and leading to persistent infection, favoring as well secondary bacterial infections or viral rebound. However, further studies should be conducted to evaluate the functional role of immune checkpoints in advanced stages of PRRSV infection and explore a possible T-cell exhaustion state.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno , Síndrome Respiratória e Reprodutiva Suína/genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Transcriptoma , Animais , Biópsia , Lavagem Broncoalveolar , Biologia Computacional/métodos , Ontologia Genética , Redes Reguladoras de Genes , Interações Hospedeiro-Patógeno/genética , Contagem de Leucócitos , Síndrome Respiratória e Reprodutiva Suína/diagnóstico , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Suínos , Avaliação de Sintomas , Carga Viral , Virulência
2.
BMC Gastroenterol ; 22(1): 516, 2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36513968

RESUMO

BACKGROUND: T1 colorectal cancer (CRC) without histological high-risk factors for lymph node metastasis (LNM) can potentially be cured by endoscopic resection, which is associated with significantly lower morbidity, mortality and costs compared to radical surgery. An important prerequisite for endoscopic resection as definite treatment is the histological confirmation of tumour-free resection margins. Incomplete resection with involved (R1) or indeterminate (Rx) margins is considered a strong risk factor for residual disease and local recurrence. Therefore, international guidelines recommend additional surgery in case of R1/Rx resection, even in absence of high-risk factors for LNM. Endoscopic full-thickness resection (eFTR) is a relatively new technique that allows transmural resection of colorectal lesions. Local scar excision after prior R1/Rx resection of low-risk T1 CRC could offer an attractive minimal invasive strategy to achieve confirmation about radicality of the previous resection or a second attempt for radical resection of residual luminal cancer. However, oncologic safety has not been established and long-term data are lacking. Besides, surveillance varies widely and requires standardization. METHODS/DESIGN: In this nationwide, multicenter, prospective cohort study we aim to assess feasibility and oncological safety of completion eFTR following incomplete resection of low-risk T1 CRC. The primary endpoint is to assess the 2 and 5 year luminal local tumor recurrence rate. Secondary study endpoints are to assess feasibility, percentage of curative eFTR-resections, presence of scar tissue and/or complete scar excision at histopathology, safety of eFTR compared to surgery, 2 and 5 year nodal and/or distant tumor recurrence rate and 5-year disease-specific and overall-survival rate. DISCUSSION: Since the implementation of CRC screening programs, the diagnostic rate of T1 CRC is steadily increasing. A significant proportion is not recognized as cancer before endoscopic resection and is therefore resected through conventional techniques primarily reserved for benign polyps. As such, precise histological assessment is often hampered due to cauterization and fragmentation and frequently leads to treatment dilemmas. This first prospective trial will potentially demonstrate the effectiveness and oncological safety of completion eFTR for patients who have undergone a previous incomplete T1 CRC resection. Hereby, substantial surgical overtreatment may be avoided, leading to treatment optimization and organ preservation. Trial registration Nederlands Trial Register, NL 7879, 16 July 2019 ( https://trialregister.nl/trial/7879 ).


Assuntos
Neoplasias Colorretais , Recidiva Local de Neoplasia , Humanos , Cicatriz/complicações , Cicatriz/patologia , Neoplasias Colorretais/patologia , Metástase Linfática , Estudos Multicêntricos como Assunto , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasia Residual/patologia , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento
3.
Phys Chem Chem Phys ; 24(11): 7134-7143, 2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35262146

RESUMO

Armchair graphene nanoribbons, when forming a superlattice, can be classified into different topological phases, with or without edge states. By means of tight-binding and classical molecular dynamics (MD) simulations, we studied the electronic and mechanical properties of some of these superlattices. MD shows that fracture in modulated superlattices is brittle, as for unmodulated ribbons, and occurs at the thinner regions, with staggered superlattices achieving a larger fracture strain than inline superlattices. We found a general mechanism to induce a topological transition with strain, related to the electronic properties of each segment of the superlattice, and by studying the sublattice polarization we were able to characterize the transition and the response of these states to the strain. For the cases studied in detail here, the topological transition occurred at ∼3-5% strain, well below the fracture strain. The topological states of the superlattice - if present - are robust to strain even close to fracture. The topological transition was characterized by means of the sublattice polarization of the states.

4.
Nanotechnology ; 32(4): 045709, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33045683

RESUMO

There are many simulation studies of mechanical properties of graphene nanoribbons (GNR), but there is a lack of agreement regarding elastic and plastic behavior. In this paper we aim to analyze mechanical properties of finite-size GNR, including elastic modulus and fracture, as a function of ribbon size. We present classical molecular dynamics simulations for three different empirical potentials which are often used for graphene simulations: AIREBO, REBO-scr and REAXFF. Ribbons with and without H-passivation at the borders are considered, and the effects of strain rate and different boundaries are also explored. We focus on zig-zag GNR, but also include some armchair GNR examples. Results are strongly dependent on the empirical potential employed. Elastic modulus under uniaxial tension can depend on ribbon size, unlike predictions from continuum-scale models and from some atomistic simulations, and fracture strain and progress vary significantly amongst the simulated potentials. Because of that, we have also carried out quasi-static ab-initio simulations for a selected size, and find that the fracture process is not sudden, instead the wave function changes from Blöch states to a strong interaction between localized waves, which decreases continuously with distance. All potentials show good agreement with DFT in the linear elastic regime, but only the REBO-scr potential shows reasonable agreement with DFT both in the nonlinear elastic and fracture regimes. This would allow more reliable simulations of GNRs and GNR-based nanostructures, to help interpreting experimental results and for future technological applications.

5.
Rheumatol Int ; 41(7): 1329-1335, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33891159

RESUMO

Monocytes play a key role in pathophysiology of antiphospholipid syndrome (APS), nevertheless it is unclear if microRNA expression is associated with particular APS features. Identify whether miR-19b-3p and miR-20a-5p expression in monocytes are associated with hallmarks of the APS. Fifty-seven APS patients and 18 healthy controls were studied. Expression of miR-19b-3p and miR-20a-5p was measured in monocytes by RT-qPCR. Both miR-19b-3p (AUC = 0.835, 95% CI 0.733-0.938; P < 0.001) and miR-20a-5p (AUC = 0.857, 0.757-0.957; P < 0.001) discriminated APS patients from healthy individuals. A cut-off point of 1.98 for miR-19-3p and 2.18 for miR-20a-5p showed that APS patients with low microRNA expression had higher levels of IgM and IgG anticardiolipin antibodies than patients with high microRNA expression. In addition, APS patients with low microRNA expression had higher IgG anti-ß2 glycoprotein I antibody levels than their counterparts with high microRNA expression. Finally, miR-19b-3p and miR-20a-5p expression levels were significantly higher in APS patients using oral anticoagulants. Monocyte expression of miR-19b-3p and miR-20a-5p is low in APS, and patients with the lowest microRNA expression presented the highest levels of antiphospholipid antibodies.


Assuntos
Anticorpos Antifosfolipídeos/sangue , Síndrome Antifosfolipídica/metabolismo , MicroRNAs/metabolismo , Monócitos/metabolismo , Adulto , Síndrome Antifosfolipídica/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Clin Oral Investig ; 25(6): 3905-3918, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33415377

RESUMO

OBJECTIVE: To evaluate the hard tissue volumetric and soft tissue contour linear changes in implants with two different implant surface characteristics after a ligature-induced peri-implantitis. MATERIAL AND METHODS: In eight beagle dogs, implants with the same size and diameter but distinct surface characteristics were placed in the healed mandibular sites. Test implants had an external monolayer of multi-phosphonate molecules (B+), while control implants were identical but without the phosphonate-rich surface. Once the implants were osseointegrated, oral hygiene was interrupted and peri-implantitis was induced by placing subgingival ligatures. After 16 weeks, the ligatures were removed and peri-implantitis progressed spontaneously. Bone to implant contact (BIC) and bone loss (BL) were assessed three-dimensionally with Micro-Ct (µCT). Dental casts were optically scanned and the obtained digitalized standard tessellation language (STL) images were used to assess the soft tissue vertical and horizontal contour linear changes. RESULTS: Reduction of the three-dimensional BIC percentage during the induction and progression phases of the experimental peri-implantitis was similar for both the experimental and control implants, without statistically significant differences between them. Soft tissue analysis revealed for both implant groups an increase in horizontal dimension after the induction of peri-implantitis, followed by a decrease after the spontaneous progression period. In the vertical dimension, a soft tissue dehiscence was observed in both groups, being more pronounced at the buccal aspect. CONCLUSIONS: The added phosphonate-rich surface did not provide a more resistant environment against experimental peri-implantitis, when assessed by the changes in bone volume and soft tissue contours. CLINICAL RELEVANCE: Ligature-induced peri-implantitis is a validated model to study the tissue changes occurring during peri-implantitis. It was hypothesized that a stronger osseointegration mediated by the chemical bond of a phosphonate-rich implant surface would develop an environment more resistant to the inflammatory changes occurring after experimental peri-implantitis. These results, however, indicate that the hard and soft tissue destructive changes occurring at both the induction and progression phases of experimental peri-implantitis were not influenced by the quality of osseointegration.


Assuntos
Perda do Osso Alveolar , Implantes Dentários , Peri-Implantite , Animais , Cães , Mandíbula , Osseointegração
7.
Lupus ; 29(5): 482-489, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32122227

RESUMO

OBJECTIVE: To explore whether the IFNL3/4 rs12979860 genotype may influence serum levels or production of interferon-inducible protein-10 (IP-10) by peripheral blood mononuclear cells from patients with systemic lupus erythematosus (SLE). METHODS: Sixty-six patients with SLE and 22 healthy blood donors (controls) were included. The IFNL3/4 rs12979860 polymorphism was genotyped by real-time polymerase chain reaction. IP-10 levels in sera supernatants of IFNα stimulated peripheral blood mononuclear cells were measured by enzime-linked immunosorbent assay. RESULTS: Allelic frequencies were CC (29%), CT (52%) and TT (20%) in SLE, and CC (32%), CT (41%) and TT (27%) in healthy controls. Median serum IP-10 levels were higher in SLE patients than in controls (190.8 versus 118.1 pg/ml; p < 0.001), particularly in those with high disease activity (278.5 versus 177.2 pg/ml; p = 0.037). However, serum IP-10 levels were not influenced by IFNL3/4 genotypes. Higher IP-10 production by peripheral blood mononuclear cells was found in both SLE patients (median 519.3 versus 207.6 pg/ml; p = 0.012) and controls (median 454.0 versus 201.7 pg/ml; p = 0.034) carrying the IFNL3/4 C allele compared with carriers of the T allele. CONCLUSIONS: Although IFNL3/4 rs12979860 allele C does not appear to influence serum IP-10 levels in SLE, it plays an important role in the production of IP-10 by peripheral blood mononuclear cells after IFNα stimulation.


Assuntos
Quimiocina CXCL10/sangue , Interferons/genética , Interleucinas/genética , Leucócitos Mononucleares/metabolismo , Lúpus Eritematoso Sistêmico/genética , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Lúpus Eritematoso Sistêmico/sangue , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
8.
Alcohol Alcohol ; 55(4): 374-381, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32300797

RESUMO

AIMS: To determinate if offspring of alcohol-dependent patients (OA) process affective stimuli and alcohol-related cues in a different manner than control subjects do. METHODS: Event-related potentials (early posterior negativity [EPN]/ late positive potential [LPP]) and event-related oscillations (Theta) were obtained by electroencephalographic (EEG) recording during the viewing of International Affective Picture System (IAPS) images with positive, negative and neutral valence, as well as alcohol-related cues. The total sample was comprised of 60 participants, divided into two groups: one group consisted of OA (30) and the control group of participants with negative family history of alcohol use disorders (30). RESULTS: Theta power analysis implies a significant interaction between condition, region and group factors. Post-hoc analysis indicates an increased theta power for the OA at different regions, during pleasant (frontal, central, parietal, occipital, right temporal); unpleasant (frontal, central, occipital); alcohol (frontal, central, parietal, occipital, right and left temporal) and neutral (occipital) cues. There are no group differences regarding any of the event-related potential measurements (EPN/LPP). CONCLUSIONS: There is evidence of alterations in the processing of affective stimuli and alcohol-related information, evidenced by changes in theta brain oscillations. These alterations are characterized by an increased emotional reactivity, evidenced by increased theta at posterior sites. There is also an increased recruitment of emotion control, which could be a compensation mechanism, evidenced by increased theta power at anterior sites during affective stimuli and alcohol cues.


Assuntos
Alcoolismo/fisiopatologia , Alcoolismo/psicologia , Filho de Pais com Deficiência/psicologia , Emoções , Adolescente , Adulto , Sinais (Psicologia) , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino
9.
J Investig Allergol Clin Immunol ; 30(4): 254-263, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31188129

RESUMO

BACKGROUND AND OBJECTIVE: Hypersensitivity reactions to oxaliplatin may affect prognosis by jeopardizing the timely completion of scheduled treatment sessions or by forcing reactive patients into unexpected changes in therapy. Rapid drug desensitization (RDD) enables these patients to receive their first-choice treatments safely. However, the possible effects of RDD on the efficacy of oxaliplatin have never been studied. Objective: The objective of this study was to evaluate the effect of RDD on survival rates in oxaliplatin-hypersensitive patients. METHODS: We performed a 7-year retrospective study to compare survival between oxaliplatin-hypersensitive cases (patients receiving oxaliplatin by RDD) and nonallergic controls (patients receiving standard oxaliplatin infusions). The primary endpoint of this study was overall survival (OS) in cases and controls (Kaplan-Meier method with log-rank test comparisons). RESULTS: OS was 23.7 months (95%CI, 15.3-30.9) for the 67 cases who underwent 337 RDDs, while for controls (n=143), OS was 34.5 months (95%CI, 21.7-55.5). There were no significant differences between the groups (HR, 1.42; 95%CI, 0.93-2.17; P =.104). CONCLUSIONS: Survival outcomes of oxaliplatin-hypersensitive patients who received oxaliplatin via RDD did not differ significantly from those of control patients who received oxaliplatin via standard administration. Receiving oxaliplatin by means of RDD might be an effective therapeutic alternative for oxaliplatin-hypersensitive patients.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Dessensibilização Imunológica/métodos , Hipersensibilidade a Drogas/terapia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/terapia , Oxaliplatina/uso terapêutico , Adulto , Idoso , Antineoplásicos/efeitos adversos , Neoplasias Colorretais/mortalidade , Hipersensibilidade a Drogas/imunologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxaliplatina/efeitos adversos , Estudos Retrospectivos , Testes Cutâneos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
10.
Radiologe ; 59(Suppl 1): 46-50, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31616956

RESUMO

International guidelines dictate that magnetic resonance imaging (MRI) should be part of the primary standard work up of patients with rectal cancer because MRI can accurately identify the main risk factors for local recurrence and stratify patients into a differentiated treatment. The role of endoscopic ultrasound (EUS) is restricted to staging of superficial tumors because EUS is able to differentiate between T1 and T2 rectal cancer. Recent guidelines recommend the addition of diffusion-weighted (DWI) MRI to clinical and endoscopic assessment of response to preoperative radiochemotherapy (RCT). MRI is able to identify significant tumor regression which may alter the surgical approach.


Assuntos
Recidiva Local de Neoplasia , Neoplasias Retais , Endossonografia , Humanos , Imageamento por Ressonância Magnética , Estadiamento de Neoplasias , Neoplasias Retais/diagnóstico por imagem
11.
Radiologe ; 59(9): 799-803, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-31463539

RESUMO

International guidelines dictate that magnetic resonance imaging (MRI) should be part of the primary standard work up of patients with rectal cancer because MRI can accurately identify the main risk factors for local recurrence and stratify patients into a differentiated treatment. The role of endoscopic ultrasound (EUS) is restricted to staging of superficial tumors because EUS is able to differentiate between T1 and T2 rectal cancer. Recent guidelines recommend the addition of diffusion-weighted (DWI) MRI to clinical and endoscopic assessment of response to preoperative radiochemotherapy (RCT). MRI is able to identify significant tumor regression which may alter the surgical approach.


Assuntos
Recidiva Local de Neoplasia , Neoplasias Retais , Endossonografia/métodos , Humanos , Imageamento por Ressonância Magnética , Estadiamento de Neoplasias/normas , Neoplasias Retais/diagnóstico por imagem
12.
Am J Transplant ; 18(9): 2238-2249, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29900673

RESUMO

Immunosuppression following solid organ transplantation (SOT) has a deleterious effect on cellular immunity leading to frequent and prolonged viral infections. To better understand the relationship between posttransplant immunosuppression and circulating virus-specific T cells, we prospectively monitored the frequency and function of T cells directed to a range of latent (CMV, EBV, HHV6, BK) and lytic (AdV) viruses in 16 children undergoing liver transplantation for up to 1 year posttransplant. Following transplant, there was an immediate decline in circulating virus-specific T cells, which recovered posttransplant, coincident with the introduction and subsequent routine tapering of immunosuppression. Furthermore, 12 of 14 infections/reactivations that occurred posttransplant were successfully controlled with immunosuppression reduction (and/or antiviral use) and in all cases we detected a temporal increase in the circulating frequency of virus-specific T cells directed against the infecting virus, which was absent in 2 cases where infections remained uncontrolled by the end of follow-up. Our study illustrates the dynamic changes in virus-specific T cells that occur in children following liver transplantation, driven both by active viral replication and modulation of immunosuppression.


Assuntos
Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto/imunologia , Imunidade Celular/imunologia , Transplante de Fígado/efeitos adversos , Linfócitos T/imunologia , Viroses/imunologia , Vírus/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Rejeição de Enxerto/patologia , Humanos , Terapia de Imunossupressão , Imunossupressores/uso terapêutico , Lactente , Masculino , Complicações Pós-Operatórias , Prognóstico , Estudos Prospectivos , Fatores de Risco , Transplantados , Carga Viral , Viroses/virologia , Replicação Viral , Adulto Jovem
13.
Biochim Biophys Acta Mol Basis Dis ; 1864(4 Pt A): 1148-1159, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29378302

RESUMO

Alzheimer's disease (AD) is characterized by progressive memory loss and dementia. The strong correlation between cognitive decline and the loss of synapses supports the idea that synaptic damage is a relevant pathogenic mechanism underlying AD progression. It has been shown that amyloid beta oligomers (AßOs) induce synaptotoxicity ultimately leading to the reduction of dendritic spine density, which underlies cognitive damage. However, the signaling pathways connecting AßOs to synaptic dysfunction have not been completely elucidated. In this review, we have gathered evidence on AßOs receptors and the signaling pathways involved in synaptic damage. We make special emphasis on a new AßOs induced axis that involves the tyrosine kinase ephrin receptor A4 (EphA4) and c-Abl tyrosine kinase activation. EphA4 is a key player in homeostatic plasticity, mediating dendritic spine remodeling and retraction. AßOs aberrantly activate EphA4 leading to dendritic spine elimination. c-Abl is activated in AßOs exposed neurons and in AD patient's brain, and the inhibition of activated c-Abl ameliorates cognitive deficits in AD mouse model. The EphA4 receptor activates c-Abl intracellular signaling. Therefore EphA4 is an emerging AßOs receptor and the activation of the EphA4/c-Abl axis would explain the synaptic spine alterations found in AD.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Proteínas Proto-Oncogênicas c-abl/metabolismo , Receptor EphA4/metabolismo , Transdução de Sinais , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Animais , Espinhas Dendríticas/genética , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/patologia , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-abl/genética , Receptor EphA4/genética , Sinapses/genética , Sinapses/metabolismo , Sinapses/patologia
14.
Opt Lett ; 43(11): 2523-2526, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29856420

RESUMO

The design and performance of borate glass samples compositionally pre-designed to be femtosecond laser writable via laser-induced ion migration is reported in this Letter. It is demonstrated that borate glasses modified on purpose with small amounts of La2O3 and Na2O can be straightforwardly used to produce high-index contrast (Δn) waveguides by femtosecond-laser-assisted ion migration. The positive Δn of the waveguides is caused by the local enrichment of La2O3 in the guiding region with a slope of 8·10-3(mol.%)-1. The value of this is consistent with numerical aperture measurements of the waveguides and local compositional measurements at the guiding region performed by energy-dispersive x-ray micro-analysis. The maximum achievable Δn values can be controlled through the initial La2O3 content of the glass. Maximum Δn values >10-2 for samples with just 5.5 mol. % of La2O3 have been produced. This compositional design approach could be potentially used to produce highly efficient femtosecond laser writeable glasses in other glass families.

15.
Phys Chem Chem Phys ; 20(24): 16347-16353, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29683154

RESUMO

We studied the soft landing of Ni atoms on a previously damaged graphene sheet by means of molecular dynamics simulations. We found a monotonic decrease of the cluster frequency as a function of its size, but few big clusters comprise an appreciable fraction of the total number of Ni atoms. The aggregation of Ni atoms is also modeled by means of a simple phenomenological model. The results are in clear contrast with the case of hard or energetic landing of metal atoms, where there is a tendency to form mono-disperse metal clusters. This behavior is attributed to the high diffusion of unattached Ni atoms, together with vacancies acting as capture centers. The findings of this work show that a simple study of the energetics of the system is not enough in the soft landing regime, where it is unavoidable to also consider the growth process of metal clusters.

16.
Med Vet Entomol ; 32(1): 35-40, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28857265

RESUMO

Several species of Culicoides (Diptera: Ceratopogonidae) are vectors of pathogens, such as the bluetongue (BTV) and Schmallenberg (SBV) viruses, which cause important diseases in domestic and wild ruminants. As wild ruminants can contribute to overwintering and epizootics of both diseases, knowledge of the host-feeding behaviour of Culicoides in natural ecosystems is important to better understand their epidemiology. Blood-engorged Culicoides females trapped in natural areas inhabited by different wild ruminant species were genetically analysed to identify host species. The origin of bloodmeals was identified in 114 females of 14 species of Culicoides. A total of 104 (91.1%) Culicoides fed on mammals and 10 (8.9%) on birds. The most abundant host identified was red deer (66.7%), followed by humans (13%) and fallow deer (6.1%). Eleven of the 14 species of Culicoides fed exclusively on mammalian hosts. Among them, five are mammalophilic species considered to be important BTV and/or SBV vectors. The results of the present study confirm that Culicoides imicola, Culicoides obsoletus, Culicoides scoticus, Culicoides pulicaris and Culicoides punctatus fed on wild ruminants, and therefore support the hypothesis that these species can act as bridge vectors by facilitating the circulation of pathogens between wild and domestic ruminant communities.


Assuntos
Ceratopogonidae/fisiologia , Ecossistema , Insetos Vetores/fisiologia , Animais , Vírus Bluetongue/isolamento & purificação , Ceratopogonidae/virologia , Comportamento Alimentar , Feminino , Insetos Vetores/virologia , Orthobunyavirus/isolamento & purificação , Ruminantes/fisiologia , Ruminantes/virologia , Espanha , Especificidade da Espécie
17.
Alcohol Alcohol ; 53(6): 699-706, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30020398

RESUMO

AIMS: To assess inhibitory processes and the ongoing event-related potential (ERP) activity of offspring of alcoholics (OA) during a Go/No-Go task, with the purpose of characterizing possible psychophysiological endophenotypes for alcohol-dependent vulnerability. SHORT SUMMARY: EEG recordings and ERP measurements of young adults with positive and negative family history of alcoholism where obtained while they performed a Go/No-Go task to assess inhibitory processes. Offspring of alcoholics showed a different ERP pattern compared to the control group and exerted greater effort than the control group. METHODS: ERP measurements were obtained by electroencephalogram (EEG) recordings of 65 participants divided into two groups: one group of 30 subjects with positive family history of alcoholism and a control group of 35 subjects with negative family history of alcoholism. They performed a Go/No-Go task, where each individual was required to classify visual stimuli by colour (Go) and inhibit their response to a No-Go signal. RESULTS: OA have higher P3 amplitudes during the Go condition in all of the regions analysed and higher No-Go P3 amplitudes than control subjects in the frontal region. Unlike controls, OA have no differences between the P3 amplitudes across conditions. CONCLUSIONS: The absence of differences between the P3 Go and No-Go observed in the OA group can be interpreted as a possible alteration related with inhibition, in a way that they may need to recruit similar resources for inhibitory and classificational processes for both conditions. Therefore, the P3 component may be considered as a useful endophenotype and a vulnerability marker to develop addictive behaviour.


Assuntos
Alcoólicos/psicologia , Alcoolismo/psicologia , Filho de Pais com Deficiência/psicologia , Potenciais Evocados P300/fisiologia , Inibição Psicológica , Adolescente , Adulto , Alcoolismo/genética , Alcoolismo/fisiopatologia , Estudos Transversais , Eletroencefalografia/métodos , Endofenótipos , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto Jovem
18.
Am J Gastroenterol ; 112(11): 1709-1718, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28675163

RESUMO

OBJECTIVES: To determine the efficacy and safety of cyclosporine (CyA) in a large national registry-based population of patients with steroid-refractory (SR) acute severe ulcerative colitis (ASUC) and to establish predictors of efficacy and adverse events. METHODS: Multicenter study of SR-ASUC treated with CyA, based on data from the ENEIDA registry. SR-ASUC patients treated with infliximab (IFX) or sequential rescue therapy (CyA-IFX or IFX-CyA) were used as comparators. RESULTS: Of 740 SR-ASUC patients, 377 received CyA, 131 IFX and 63 sequential rescue therapy. The cumulative colectomy rate was higher in the CyA (24.1%) and sequential therapy (32.7%) than in the IFX group (14.5%; P=0.01) at 3 months and 5 years. There were no differences in early and late colectomy between CyA and IFX in patients treated after 2005. 62% of patients receiving CyA remained colectomy-free in the long term (median 71 months). There were no differences in mortality between CyA (2.4%), IFX (1.5%) and sequential therapy (0%; P=0.771). The proportion of patients with serious adverse events (SAEs) was lower in CyA (15.4%) than in IFX treated patients (26.5%) or sequential therapy (33.4%; P<0.001). This difference in favor of CyA was maintained when only patients treated after 2005 were analyzed. CONCLUSIONS: Treatment with CyA showed a lower rate of SAE and a similar efficacy to that of IFX thereby supporting the use of either CyA or IFX in SR-ASUC. In addition, the risk-benefit of sequential CyA-IFX for CyA non-responders is acceptable.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Sistema de Registros , Doença Aguda , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Colectomia/estatística & dados numéricos , Feminino , Fármacos Gastrointestinais/uso terapêutico , Humanos , Infecções/induzido quimicamente , Infliximab/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mortalidade , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
19.
Am J Gastroenterol ; 112(1): 120-131, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27958281

RESUMO

OBJECTIVES: The aims of this study were to assess the risk of relapse after discontinuation of anti-tumor necrosis factor (anti-TNF) drugs in patients with inflammatory bowel disease (IBD), to identify the factors associated with relapse, and to evaluate the overcome after retreatment with the same anti-TNF in those who relapsed. METHODS: This was a retrospective, observational, multicenter study. IBD patients who had been treated with anti-TNFs and in whom these drugs were discontinued after clinical remission was achieved were included. RESULTS: A total of 1,055 patients were included. The incidence rate of relapse was 19% and 17% per patient-year in Crohn's disease and ulcerative colitis patients, respectively. In both Crohn's disease and ulcerative colitis patients in deep remission, the incidence rate of relapse was 19% per patient-year. The treatment with adalimumab vs. infliximab (hazard ratio (HR)=1.29; 95% confidence interval (CI)=1.01-1.66), elective discontinuation of anti-TNFs (HR=1.90; 95% CI=1.07-3.37) or discontinuation because of adverse events (HR=2.33; 95% CI=1.27-2.02) vs. a top-down strategy, colonic localization (HR=1.51; 95% CI=1.13-2.02) vs. ileal, and stricturing behavior (HR=1.5; 95% CI=1.09-2.05) vs. inflammatory were associated with a higher risk of relapse in Crohn's disease patients, whereas treatment with immunomodulators after discontinuation (HR=0.67; 95% CI=0.51-0.87) and age (HR=0.98; 95% CI=0.97-0.99) were protective factors. None of the factors were predictive in ulcerative colitis patients. Retreatment of relapse with the same anti-TNF was effective (80% responded) and safe. CONCLUSIONS: The incidence rate of inflammatory bowel disease relapse after anti-TNF discontinuation is relevant. Some predictive factors of relapse after anti-TNF withdrawal have been identified. Retreatment with the same anti-TNF drug was effective and safe.


Assuntos
Adalimumab/uso terapêutico , Antirreumáticos/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Doença de Crohn/tratamento farmacológico , Desprescrições , Fatores Imunológicos/uso terapêutico , Infliximab/uso terapêutico , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Colite Ulcerativa/fisiopatologia , Colo , Constrição Patológica , Doença de Crohn/fisiopatologia , Progressão da Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Seguimentos , Humanos , Íleo , Incidência , Doenças Inflamatórias Intestinais/tratamento farmacológico , Masculino , Mesalamina/uso terapêutico , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Proteção , Recidiva , Indução de Remissão , Retratamento , Estudos Retrospectivos , Fatores de Risco , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto Jovem
20.
Inorg Chem ; 56(21): 13535-13546, 2017 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-29048915

RESUMO

Understanding the origin of cooperativity and the equilibrium temperature of transition (T1/2) displayed by the spin-crossover (SCO) compounds as well as controlling these parameters are of paramount importance for future applications. For this task, the occurrence of polymorphism, presented by a number of SCO complexes, may provide deep insight into the influence of the supramolecular organization on the SCO behavior. In this context, herein we present a novel family of mononuclear octahedral FeII complexes with formula cis-[Fe(bqen)(NCX)2], where bqen is the chelating tetradentate ligand N,N'-bis(8-quinolyl)ethane-1,2-diamine and X = S, Se. Depending on the preparation method, these compounds crystallize in either the orthorhombic or the trigonal symmetry systems. While the orthorhombic phase is composed of a racemic mixture of mononuclear complexes (polymorph I), the trigonal phase contains only one of the two possible enantiomers (Λ or Δ), thereby generating a chiral crystal (polymorph II). The four derivatives undergo SCO behavior with well-differentiated T1/2 values occurring in the interval 90-233 K. On one hand, T1/2 is about 110 K (polymorph I) and 87 K (polymorph II) higher for the selenocyanate derivatives in comparison to those for their thiocyanate counterparts. These differences in T1/2 are ascribed not only to the higher ligand field induced by the selenocyanate anion but also to a remarkable difference in the structural reorganization of the [FeN6] coordination core upon SCO. Likewise, the higher cooperativity observed for the thiocyanate derivatives seems to be related to their stronger intermolecular interactions within the crystal. On the other hand, T1/2 is about 53 K (thiocyanate) and 29 K (selenocyanate) higher for the trigonal polymorph II in comparison to those for the orthorhombic polymorph I. These differences, and the small changes observed in cooperativity, stem from the slightly different hetero- and homochiral crystal packing generated by the cis-[Fe(bqen)(NCX)2] molecules, which determines subtle adaptations in the intermolecular contacts and the FeII coordination core.

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