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1.
Nano Lett ; 24(12): 3678-3685, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38471109

RESUMO

Control over the optical properties of atomically thin two-dimensional (2D) layers, including those of transition metal dichalcogenides (TMDs), is needed for future optoelectronic applications. Here, the near-field coupling between TMDs and graphene/graphite is used to engineer the exciton line shape and charge state. Fano-like asymmetric spectral features are produced in WS2, MoSe2, and WSe2 van der Waals heterostructures combined with graphene, graphite, or jointly with hexagonal boron nitride (h-BN) as supporting or encapsulating layers. Furthermore, trion emission is suppressed in h-BN encapsulated WSe2/graphene with a neutral exciton red shift (44 meV) and binding energy reduction (30 meV). The response of these systems to electron beam and light probes is well-described in terms of 2D optical conductivities of the involved materials. Beyond fundamental insights into the interaction of TMD excitons with structured environments, this study opens an unexplored avenue toward shaping the spectral profile of narrow optical modes for application in nanophotonic devices.

2.
Vet Res ; 55(1): 53, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658996

RESUMO

Gene expression for Th1/Th2 cytokines (IL-4 and IFN-É£), regulatory cytokines (TGF-ß and IL-10) and the transcriptional factor FoxP3 was analyzed in the liver and hepatic lymph nodes (HLN) from sheep immunized with partially protective and non-protective vaccine candidates and challenged with Fasciola hepatica. FoxP3 T cells were also evaluated by immunohistochemistry (IHQ). The most remarkable difference between the partially protected vaccinated (V1) group and the non-protected vaccinated (V2) group was a more severe expansion of FoxP3 T cells recorded by IHQ in both the liver and HLN of the V2 group as compared to the V1 group, whereas no differences were found between the V2 group and the infected control (IC) group. Similar results were recorded for FoxP3 gene expression although significant differences among V1 and V2 groups were only significant in the HLN, while FoxP3 gene expression was very similar in the V2 and IC groups both in the liver and HLN. No significant differences for the remaining cytokines were recorded between the V1 and V2 groups, but in the liver the V2 group shows significant increases of IFN-É£ and IL-10 as compared to the uninfected control (UC) group whereas the V1 group did not. The lower expansion of FoxP3 T cells and lower increase of IFN-É£ and IL-10 in the partially protected vaccinated group may be related with lower hepatic lesions and fluke burdens recorded in this group as compared to the other two infected groups. The most relevant change in regulatory cytokine gene expression was the significant increase of TGF-ß in the liver of IC, V1 and V2 groups as compared to the UC group, which could be related to hepatic lesions.


Assuntos
Citocinas , Fasciola hepatica , Fasciolíase , Fatores de Transcrição Forkhead , Doenças dos Ovinos , Animais , Fasciolíase/veterinária , Fasciolíase/prevenção & controle , Fasciolíase/imunologia , Fasciola hepatica/imunologia , Ovinos , Fatores de Transcrição Forkhead/metabolismo , Doenças dos Ovinos/prevenção & controle , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/parasitologia , Citocinas/metabolismo , Fígado/parasitologia , Fígado/imunologia , Vacinas/imunologia , Vacinas/administração & dosagem , Células Th1/imunologia , Linfonodos/imunologia , Feminino , Células Th2/imunologia
3.
Vet Res ; 54(1): 2, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627694

RESUMO

The expression of proinflammatory (IL-1ß, IFN-γ, TNF-α) and regulatory (IL-10, TGF-ß, IL-4) cytokines, as well as the transcription factor FoxP3, was quantified in the liver and hepatic lymph node (HLN) of sheep primoinfected and reinfected with Fasciola hepatica at early (4, 8 and 16 days post-infection [dpi]) and late (100 dpi) stages. The liver exerted a Th2 immune response at very early stages after the primoinfection with F. hepatica that induced the downregulation of IFN-γ, followed by a Th1/Th2/Treg response although the late stages were characterised by the expression of Th1/Th2 immune mediators. Contrarily, in reinfected sheep a robust mixed Th1/Th2/Treg immune response was found at very early stages meanwhile at late stages we observed a Th2/Treg immune response overcoming the expression of Th1 immune mediators. However, the HLN displayed a completely different Th1/Th2/Treg expression profile compared to the liver. Primoinfections with F. hepatica in HLN induced a mixed Th1/Th2/Treg environment from early stages, establishing a Th2 immune response at a late stage. However, the reinfected sheep exerted a Th2 immune response at early stages led by the IL-4 expression in opposition to the Th1/Th2/Treg found in the liver, meanwhile at late stages the HLN of reinfected sheep exerted a mixed Th1/Th2/Treg immune response. This is the first work publishing the expression of immune mediators in the liver and HLN from reinfected sheep with F. hepatica. The study of the immune responses exerted by the natural host in the target organs directly implied in the development of F. hepatica are crucial to better understand the immunopathogenesis of the fasciolosis being a key factor to develop effective vaccines.


Assuntos
Fasciola hepatica , Fasciolíase , Doenças dos Ovinos , Ovinos , Animais , Fasciola hepatica/fisiologia , Interleucina-4 , Reinfecção/patologia , Reinfecção/veterinária , Linfócitos T Reguladores , Fasciolíase/veterinária , Fígado/patologia , Fatores de Transcrição , Imunidade , Linfonodos , Doenças dos Ovinos/patologia
4.
Plant Cell ; 31(8): 1807-1828, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31189737

RESUMO

Brassinosteroids (BRs) form a group of steroidal hormones essential for plant growth, development, and stress responses. BRs are perceived extracellularly by plasma membrane receptor-like kinases that activate an interconnected signal transduction cascade, leading to the transcriptional regulation of BR-responsive genes. TETRATRICOPEPTIDE THIOREDOXIN-LIKE (TTL) genes are specific for land plants, and their encoded proteins are defined by the presence of protein-protein interaction motives, that is, an intrinsic disordered region at the N terminus, six tetratricopeptide repeat domains, and a C terminus with homology to thioredoxins. TTL proteins thus likely mediate the assembly of multiprotein complexes. Phenotypic, molecular, and genetic analyses show that TTL proteins are positive regulators of BR signaling in Arabidopsis (Arabidopsis thaliana). TTL3 directly interacts with a constitutively active BRASSINOSTEROID INSENSITIVE1 (BRI1) receptor kinase, BRI1-SUPPRESSOR1 phosphatase, and the BRASSINAZOLE RESISTANT1 transcription factor and associates with BR-SIGNALING KINASE1, BRASSINOSTEROID INSENSITIVE2 kinases, but not with BRI1-ASSOCIATED KINASE1. A functional TTL3-green fluorescent protein (GFP) shows dual cytoplasmic plasma membrane localization. Depleting the endogenous BR content reduces plasma membrane localization of TTL3-GFP, while increasing BR content causes its plasma membrane relocalization, where it strengthens the association of BR signaling components. Our results reveal that TTL proteins promote BR responses and suggest that TTL proteins may function as scaffold proteins by bringing together cytoplasmic and plasma membrane BR signaling components.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Arabidopsis/genética , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Proteínas de Membrana/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
5.
Adicciones ; 0(0): 1778, 2022 Oct 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36200233

RESUMO

One of the factors that increase the likelihood of adolescents starting to exhibit and consolidate anti-social behavior is drug use, with a consistent pattern of consumption of different substance found in young offenders (Aebi, Bessler & Steinhausen, 2021). A cognitive-behavioral group treatment program inspired by the positive psychology approach was developed and applied to drug use in minors deprived of liberty (experimental group); the results were compared to those of a group of adolescents with the same type of drug use in the same center (active control group) at two points in time: during and after incarceration. The fall in the rate of problems associated with drug use after incarceration in the experimental group was statistically significant compared to the control group, and the effect size of the experimental condition was large (ῆ^2 = 0.55), much higher than the control group (ῆ^2 = 0.16). The treatment program has proven to be an effective tool for reducing problems associated with drug use and is especially effective in reducing alcohol and cannabis consumption.


Uno de los factores que aumentan en mayor medida la probabilidad de que los adolescentes inicien y consoliden comportamientos antisociales es el consumo de drogas, encontrándose un patrón consistente de consumo de diferentes sustancias en los menores infractores (Aebi, Bessler y Steinhausen, 2021). Para la redacción del presente trabajo se desarrolló y aplicó un programa de tratamiento, de corte cognitivo ­ conductual e inspirado en el enfoque de la psicología positiva, para el consumo de drogas en menores de edad privados de libertad (grupo experimental). Los resultados se compararon con los de un grupo de adolescentes con la misma tipología de consumo internos en el mismo Centro (grupo control activo) en dos momentos, durante y tras el internamiento. El grupo experimental redujo de manera estadísticamente significativa la tasa de problemas asociados al consumo de drogas en comparación con el grupo control tras el internamiento, siendo el tamaño del efecto de la condición experimental elevado (ῆ

6.
Glob Chang Biol ; 27(4): 836-854, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33124068

RESUMO

Earth observation-based estimates of global gross primary production (GPP) are essential for understanding the response of the terrestrial biosphere to climatic change and other anthropogenic forcing. In this study, we attempt an ecosystem-level physiological approach of estimating GPP using an asymptotic light response function (LRF) between GPP and incoming photosynthetically active radiation (PAR) that better represents the response observed at high spatiotemporal resolutions than the conventional light use efficiency approach. Modelled GPP is thereafter constrained with meteorological and hydrological variables. The variability in field-observed GPP, net primary productivity and solar-induced fluorescence was better or equally well captured by our LRF-based GPP when compared with six state-of-the-art Earth observation-based GPP products. Over the period 1982-2015, the LRF-based average annual global terrestrial GPP budget was 121.8 ± 3.5 Pg C, with a detrended inter-annual variability of 0.74 ± 0.13 Pg C. The strongest inter-annual variability was observed in semi-arid regions, but croplands in China and India also showed strong inter-annual variations. The trend in global terrestrial GPP during 1982-2015 was 0.27 ± 0.02 Pg C year-1 , and was generally larger in the northern than the southern hemisphere. Most positive GPP trends were seen in areas with croplands whereas negative trends were observed for large non-cropped parts of the tropics. Trends were strong during the eighties and nineties but levelled off around year 2000. Other GPP products either showed no trends or continuous increase throughout the study period. This study benchmarks a first global Earth observation-based model using an asymptotic light response function, improving simulations of GPP, and reveals a stagnation in the global GPP after the year 2000.


Assuntos
Mudança Climática , Ecossistema , China , Planeta Terra , Índia , Fotossíntese
7.
Vet Res ; 52(1): 99, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215335

RESUMO

The immunomodulatory capacity of F. hepatica antigens is probably one of the main reasons for the development of a driven non-protective Th2 immune response. In this study, we analysed the cellular response of hepatic lymph node cells and CD4+ T cells in terms of proliferative response, efficiency of antigen presentation and cytokine production, to F. hepatica-derived molecules, at early and late stages of the infection. Thirty-one sheep were allocated into five groups and were slaughtered at 16 dpi and 23 wpi. In order to analyse antigen-specific response, the following F. hepatica recombinant molecules were used: rFhCL1, rFhCL2, rFhCL3, rFhCB1, rFhCB2, rFhCB3, rFhStf-1, rFhStf-2, rFhStf-3 and rFhKT1. A cell proliferation assay using hepatic lymph node cells and an antigen presentation cell assay using CD4+ T cells were performed. At 16 dpi, all molecules but rFhStf-2 and rFhKT1 elicited a significant cell proliferative response on hepatic lymph node cells of infected animals. At both early and late stage of the infection, antigen presentation of rFhCB3 and rFhCL2 resulted in higher stimulation index of CD4+ T cells which was IL-2 mediated, although no statistically significant when compared to uninfected animals. Significant cytokine production (IL-4, IL-10 and IFN-γ) was conditioned by the antigen-specific cell stimulation. No CD4+ T cell exhaustion was detected in infected sheep at the chronic stage of the infection. This study addressed antigen-specific response to F. hepatica-derived molecules that are involved in key aspects of the parasite survival within the host.


Assuntos
Antígenos de Helmintos/imunologia , Fasciolíase/veterinária , Linfonodos/imunologia , Doenças dos Ovinos/imunologia , Linfócitos T/imunologia , Animais , Fasciola hepatica/fisiologia , Fasciolíase/imunologia , Fasciolíase/parasitologia , Fígado/imunologia , Masculino , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
8.
Vet Res ; 52(1): 13, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33509286

RESUMO

In this work we report the protection found in a vaccination trial performed in sheep with two different vaccines composed each one by a cocktail of antigens (rCL1, rPrx, rHDM and rLAP) formulated in two different adjuvants (Montanide ISA 61 VG (G1) and Alhydrogel®(G2)). The parameters of protection tested were fluke burden, faecal egg count and evaluation of hepatic lesions. In vaccinated group 1 we found a significant decrease in fluke burden in comparison to both unimmunised and infected control group (37.2%; p = 0.002) and to vaccinated group 2 (Alhydrogel®) (27.08%; p = 0.016). The lower fluke burden found in G1 was accompanied by a decrease in egg output of 28.71% in comparison with the infected control group. Additionally, gross hepatic lesions found in vaccine 1 group showed a significant decrease (p = 0.03) in comparison with unimmunised-infected group. The serological study showed the highest level for both IgG1 and IgG2 in animals from group 1. All these data support the hypothesis of protection found in vaccine 1 group.


Assuntos
Fasciola hepatica/imunologia , Fasciolíase/veterinária , Doenças dos Ovinos/prevenção & controle , Vacinação/veterinária , Vacinas Combinadas/farmacologia , Adjuvantes Imunológicos/farmacologia , Animais , Fasciolíase/imunologia , Fasciolíase/prevenção & controle , Ovinos , Doenças dos Ovinos/imunologia , Carneiro Doméstico
9.
Parasitol Res ; 120(8): 2897-2903, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34313806

RESUMO

A cross-sectional study was carried out to determine the seroprevalence of Toxoplasma gondii and associated risk factors in pigs in the largest pork-producing region in Cuba. Serum samples from 420 pigs, including 210 sows and 210 post-weaning pigs, were tested for antibodies against T. gondii using a commercial indirect enzyme-linked immunosorbent assay. Anti-T. gondii antibodies were detected in 56 animals (13.3%, 95% CI: 10.1-16.6). A generalized estimating equations model revealed that the risk factors associated with higher seropositivity in pigs were altitude (higher in farm's location < 250 m above sea level (masl) versus ≥ 250 masl) and age (higher in sows compared to post-weaning pigs). The results indicated that this protozoan parasite is widely distributed on pig farms in the study area, which is a public health concern since the consumption of raw or undercooked pork meat products containing tissue cysts is considered one of the main routes of T. gondii transmission worldwide. Control measures should be implemented to reduce the risk of exposure to T. gondii in pigs in Cuba.


Assuntos
Sus scrofa/parasitologia , Doenças dos Suínos , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários , Estudos Transversais , Cuba/epidemiologia , Feminino , Masculino , Fatores de Risco , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia
10.
Acta Biotheor ; 69(3): 391-415, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32816285

RESUMO

Both physiological and evolutionary criteria of biological individuality are underpinned by the idea that an individual is a functionally integrated whole. However, a precise account of functional integration has not been provided so far, and current notions are not developed in the details, especially in the case of composite systems. To address this issue, this paper focuses on the organisational dimension of two representative associations of prokaryotes: biofilms and the endosymbiosis between prokaryotes. Some critical voices have been raised against the thesis that biofilms are biological individuals. Nevertheless, it has not been investigated which structural and functional obstacles may prevent them from being fully integrated physiological or evolutionary units. By contrast, the endosymbiotic association of different species of prokaryotes has the potential for achieving a different type of physiological integration based on a common boundary and interlocked functions. This type of association had made it possible, under specific conditions, to evolve endosymbionts into fully integrated organelles. This paper therefore has three aims: first, to analyse the organisational conditions and the physiological mechanisms that enable integration in prokaryotic associations; second, to discuss the organisational differences between biofilms and prokaryotic endosymbiosis and the types of integration they achieve; finally, to provide a more precise account of functional integration based on these case studies.


Assuntos
Evolução Biológica , Células Procarióticas , Humanos , Simbiose
11.
Vet Res ; 51(1): 33, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131896

RESUMO

Fasciola hepatica has been shown to have a high capacity for immunomodulation of the host response, making the development of protective vaccines extremely difficult. One of these immunomodulation mechanisms is the impairment of dendritic cells (DC) maturation and, therefore, suppression of antigenic presentation. The aim of this study was to evaluate the pathological changes as well as the characterization of two antigen presenting cells, DC (CD1b, CD83 and MHC-II positive) and follicular dendritic cells (FDC) (CNA.42, S100 and CD83 positive) by immunohistochemistry in the hepatic lymph nodes (HLN) and livers of sheep during the early stages of infection with F. hepatica [9 and 18 days post-infection (dpi)], compared with an uninfected group (UC) as a control. The results revealed a marked hyperplasia of HLN germinal centres at 9 and, in particular, 18 dpi, with respect to the UC group, with coincidental increased expression of CNA.42 in FDC of lymphoid follicles and CD1b in the DC of paracortical areas at 18 dpi. However, the expression of MHC-II and CD83 decreased at 9 and, particularly, at 18 dpi in HLN compared with that in the UC group. Since both markers are related to active presentation of antigens by DC and FDC, the results of the present study suggest that, despite the marked hyperplasia of HLN and increase in DC and FDC numbers during early stages of infection, the DC and FDC antigenic presentation capacity, as suggested by the expression of the markers MHC-II and CD83, is suppressed by the parasite. This suppression was not observed in the liver, probably because of the low number of DC. This is the first study of the immunophenotype of DCs and FDC in sheep infected with F. hepatica.


Assuntos
Células Dendríticas Foliculares/patologia , Células Dendríticas/patologia , Fasciolíase/veterinária , Fígado/patologia , Linfonodos/patologia , Doenças dos Ovinos/patologia , Animais , Fasciola hepatica/fisiologia , Fasciolíase/patologia , Marcadores Genéticos , Ovinos
12.
J Ultrasound Med ; 38(6): 1459-1476, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30269384

RESUMO

OBJECTIVES: To compare the robustness of several methods based on quantitative ultrasound (US) texture analysis to evaluate its feasibility for extracting features from US images to use as a clinical diagnostic tool. METHODS: We compared, ranked, and validated the robustness of 5 texture-based methods for extracting textural features from US images acquired under different conditions. For comparison and ranking purposes, we used 13,171 non-US images from widely known available databases (OUTEX [University of Oulu, Oulu, Finland] and PHOTEX [Texture Lab, Heriot-Watt University, Edinburgh, Scotland]), which were specifically acquired under different controlled parameters (illumination, resolution, and rotation) from 103 textures. The robustness of those methods with better results from the non-US images was validated by using 666 fetal lung US images acquired from singleton pregnancies. In this study, 2 similarity measurements (correlation and Chebyshev distances) were used to evaluate the repeatability of the features extracted from the same tissue images. RESULTS: Three of the 5 methods (gray-level co-occurrence matrix, local binary patterns, and rotation-invariant local phase quantization) had favorably robust performance when using the non-US database. In fact, these methods showed similarity values close to 0 for the acquisition variations and delineations. Results from the US database confirmed robustness for all of the evaluated methods (gray-level co-occurrence matrix, local binary patterns, and rotation-invariant local phase quantization) when comparing the same texture obtained from different regions of the image (proximal/distal lungs and US machine brand stratification). CONCLUSIONS: Our results confirmed that texture analysis can be robust (high similarity for different condition acquisitions) with potential to be included as a clinical tool.


Assuntos
Pneumopatias/diagnóstico por imagem , Pneumopatias/fisiopatologia , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Ultrassonografia Pré-Natal/métodos , Estudos de Avaliação como Assunto , Estudos de Viabilidade , Feminino , Humanos , Pulmão/embriologia , Pneumopatias/embriologia , Gravidez , Reprodutibilidade dos Testes
13.
Orig Life Evol Biosph ; 49(3): 111-145, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31399826

RESUMO

In this review, we describe some of the central philosophical issues facing origins-of-life research and provide a targeted history of the developments that have led to the multidisciplinary field of origins-of-life studies. We outline these issues and developments to guide researchers and students from all fields. With respect to philosophy, we provide brief summaries of debates with respect to (1) definitions (or theories) of life, what life is and how research should be conducted in the absence of an accepted theory of life, (2) the distinctions between synthetic, historical, and universal projects in origins-of-life studies, issues with strategies for inferring the origins of life, such as (3) the nature of the first living entities (the "bottom up" approach) and (4) how to infer the nature of the last universal common ancestor (the "top down" approach), and (5) the status of origins of life as a science. Each of these debates influences the others. Although there are clusters of researchers that agree on some answers to these issues, each of these debates is still open. With respect to history, we outline several independent paths that have led to some of the approaches now prevalent in origins-of-life studies. These include one path from early views of life through the scientific revolutions brought about by Linnaeus (von Linn.), Wöhler, Miller, and others. In this approach, new theories, tools, and evidence guide new thoughts about the nature of life and its origin. We also describe another family of paths motivated by a" circularity" approach to life, which is guided by such thinkers as Maturana & Varela, Gánti, Rosen, and others. These views echo ideas developed by Kant and Aristotle, though they do so using modern science in ways that produce exciting avenues of investigation. By exploring the history of these ideas, we can see how many of the issues that currently interest us have been guided by the contexts in which the ideas were developed. The disciplinary backgrounds of each of these scholars has influenced the questions they sought to answer, the experiments they envisioned, and the kinds of data they collected. We conclude by encouraging scientists and scholars in the humanities and social sciences to explore ways in which they can interact to provide a deeper understanding of the conceptual assumptions, structure, and history of origins-of-life research. This may be useful to help frame future research agendas and bring awareness to the multifaceted issues facing this challenging scientific question.


Assuntos
Biologia/história , Química/história , Historiografia , Informática/história , Origem da Vida , Paleontologia/história , Filosofia/história , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , Biologia Molecular/história
14.
Acta Biotheor ; 67(2): 103-128, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30712187

RESUMO

This paper aims to provide a philosophical and theoretical account of biological communication grounded in the notion of organisation. The organisational approach characterises living systems as organised in such a way that they are capable to self-produce and self-maintain while in constant interaction with the environment. To apply this theoretical framework to the study of biological communication, we focus on a specific approach, based on the notion of influence, according to which communication takes place when a signal emitted by a sender triggers a change in the behaviour of the receiver that is functional for the sender itself. We critically analyse the current formulations of this account, that interpret what is functional for the sender in terms of evolutionary adaptations. Specifically, the adoption of this etiological functional framework may lead to the exclusion of several phenomena usually studied as instances of communication, and possibly even of entire fields of investigation such as synthetic biology. As an alternative, we reframe the influence approach in organisational terms, characterising functions in terms of contributions to the current organisation of a biological system. We develop a theoretical account of biological communication in which communicative functions are distinguished from other types of biological functions described by the organisational account (e.g. metabolic, ecological, etc.). The resulting organisational-influence approach allows to carry out causal analyses of current instances of phenomena of communication, without the need to provide etiological explanations. In such a way it makes it possible to understand in terms of communication those phenomena which realise interactive patterns typical of signalling interactions-and are usually studied as such in scientific practice-despite not being the result of evolutionary adaptations. Moreover, this approach provides operational tools to design and study communicative interactions in experimental fields such as synthetic biology.


Assuntos
Evolução Biológica , Comunicação , Modelos Teóricos , Biologia Sintética , Animais , Animais Recém-Nascidos , Humanos , Ratos , Reprodução
15.
Int J Mol Sci ; 20(1)2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30621162

RESUMO

Biostimulants are materials that when applied in small amounts are capable of promoting plant growth. Nanoparticles (NPs) and nanomaterials (NMs) can be considered as biostimulants since, in specific ranges of concentration, generally in small levels, they increase plant growth. Pristine NPs and NMs have a high density of surface charges capable of unspecific interactions with the surface charges of the cell walls and membranes of plant cells. In the same way, functionalized NPs and NMs, and the NPs and NMs with a corona formed after the exposition to natural fluids such as water, soil solution, or the interior of organisms, present a high density of surface charges that interact with specific charged groups in cell surfaces. The magnitude of the interaction will depend on the materials adhered to the corona, but high-density charges located in a small volume cause an intense interaction capable of disturbing the density of surface charges of cell walls and membranes. The electrostatic disturbance can have an impact on the electrical potentials of the outer and inner surfaces, as well as on the transmembrane electrical potential, modifying the activity of the integral proteins of the membranes. The extension of the cellular response can range from biostimulation to cell death and will depend on the concentration, size, and the characteristics of the corona.


Assuntos
Nanopartículas , Nanoestruturas , Plantas/metabolismo , Equilíbrio Ácido-Base , Cobre/metabolismo , Concentração de Íons de Hidrogênio , Membranas Intracelulares/metabolismo , Concentração Osmolar , Oxirredução , Coroa de Proteína/metabolismo , Eletricidade Estática , Titânio/metabolismo
16.
Vet Res ; 49(1): 56, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29970179

RESUMO

The expression of T regulatory cells (Foxp3), regulatory (interleukin [IL]-10 and transforming growth factor beta [TGF-ß]) and proinflammatory (tumor necrosis factor alpha [TNF-α] and interleukin [IL]-1ß) cytokines was quantified using real time polymerase chain reaction (qRT-PCR) in the liver of sheep during early stages of infection with Fasciola hepatica (1, 3, 9, and 18 days post-infection [dpi]). Portal fibrosis was also evaluated by Masson's trichrome stain as well as the number of Foxp3+ cells by immunohistochemistry. Animals were divided into three groups: (a) group 1 was immunized with recombinant cathepsin L1 from F. hepatica (FhCL1) in Montanide adjuvant and infected; (b) group 2 was uniquely infected with F. hepatica; and (c) group 3 was the control group, unimmunized and uninfected. An overexpression of regulatory cytokines of groups 1 and 2 was found in all time points tested in comparison with group 3, particularly at 18 dpi. A significant increase of the number of Foxp3+ lymphocytes in groups 1 and 2 was found at 9 and 18 dpi relative to group 3. A progressive increase in portal fibrosis was found in groups 1 and 2 in comparison with group 3. In this regard, group 1 showed smaller areas of fibrosis than group 2. There was a significant positive correlation between Foxp3 and IL-10 expression (by immunohistochemistry and qRT-PCR) just as between portal fibrosis and TGF-ß gene expression. The expression of proinflammatory cytokines increased gradually during the experience. These findings suggest the induction of a regulatory phenotype by the parasite that would allow its survival at early stages of the disease when it is more vulnerable.


Assuntos
Citocinas/genética , Fasciola hepatica/fisiologia , Fasciolíase/veterinária , Fatores de Transcrição Forkhead/genética , Expressão Gênica , Doenças dos Ovinos/imunologia , Animais , Citocinas/metabolismo , Fasciolíase/imunologia , Fasciolíase/virologia , Fatores de Transcrição Forkhead/metabolismo , Fígado/parasitologia , Ovinos , Doenças dos Ovinos/virologia
17.
Am J Obstet Gynecol ; 217(2): 196.e1-196.e14, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28342715

RESUMO

BACKGROUND: Prediction of neonatal respiratory morbidity may be useful to plan delivery in complicated pregnancies. The limited predictive performance of the current diagnostic tests together with the risks of an invasive procedure restricts the use of fetal lung maturity assessment. OBJECTIVE: The objective of the study was to evaluate the performance of quantitative ultrasound texture analysis of the fetal lung (quantusFLM) to predict neonatal respiratory morbidity in preterm and early-term (<39.0 weeks) deliveries. STUDY DESIGN: This was a prospective multicenter study conducted in 20 centers worldwide. Fetal lung ultrasound images were obtained at 25.0-38.6 weeks of gestation within 48 hours of delivery, stored in Digital Imaging and Communication in Medicine format, and analyzed with quantusFLM. Physicians were blinded to the analysis. At delivery, perinatal outcomes and the occurrence of neonatal respiratory morbidity, defined as either respiratory distress syndrome or transient tachypnea of the newborn, were registered. The performance of the ultrasound texture analysis test to predict neonatal respiratory morbidity was evaluated. RESULTS: A total of 883 images were collected, but 17.3% were discarded because of poor image quality or exclusion criteria, leaving 730 observations for the final analysis. The prevalence of neonatal respiratory morbidity was 13.8% (101 of 730). The quantusFLM predicted neonatal respiratory morbidity with a sensitivity, specificity, positive and negative predictive values of 74.3% (75 of 101), 88.6% (557 of 629), 51.0% (75 of 147), and 95.5% (557 of 583), respectively. Accuracy was 86.5% (632 of 730) and positive and negative likelihood ratios were 6.5 and 0.3, respectively. CONCLUSION: The quantusFLM predicted neonatal respiratory morbidity with an accuracy similar to that previously reported for other tests with the advantage of being a noninvasive technique.


Assuntos
Pulmão/diagnóstico por imagem , Pulmão/embriologia , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Taquipneia/epidemiologia , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Recém-Nascido , Pulmão/patologia , Masculino , Morbidade , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos
18.
Fetal Diagn Ther ; 41(4): 265-272, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27509017

RESUMO

OBJECTIVES: Quantitative texture analysis has been proposed to extract robust features from the ultrasound image to detect subtle changes in the textures of the images. The aim of this study was to evaluate the feasibility of quantitative cervical texture analysis to assess cervical tissue changes throughout pregnancy. METHODS: This was a cross-sectional study including singleton pregnancies between 20.0 and 41.6 weeks of gestation from women who delivered at term. Cervical length was measured, and a selected region of interest in the cervix was delineated. A model to predict gestational age based on features extracted from cervical images was developed following three steps: data splitting, feature transformation, and regression model computation. RESULTS: Seven hundred images, 30 per gestational week, were included for analysis. There was a strong correlation between the gestational age at which the images were obtained and the estimated gestational age by quantitative analysis of the cervical texture (R = 0.88). DISCUSSION: This study provides evidence that quantitative analysis of cervical texture can extract features from cervical ultrasound images which correlate with gestational age. Further research is needed to evaluate its applicability as a biomarker of the risk of spontaneous preterm birth, as well as its role in cervical assessment in other clinical situations in which cervical evaluation might be relevant.


Assuntos
Colo do Útero/diagnóstico por imagem , Idade Gestacional , Adulto , Colo do Útero/anatomia & histologia , Estudos Transversais , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez
19.
Proc Natl Acad Sci U S A ; 108(7): 2678-83, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21282624

RESUMO

Quantitative estimates of the economic damages of climate change usually are based on aggregate relationships linking average temperature change to loss in gross domestic product (GDP). However, there is a clear need for further detail in the regional and sectoral dimensions of impact assessments to design and prioritize adaptation strategies. New developments in regional climate modeling and physical-impact modeling in Europe allow a better exploration of those dimensions. This article quantifies the potential consequences of climate change in Europe in four market impact categories (agriculture, river floods, coastal areas, and tourism) and one nonmarket impact (human health). The methodology integrates a set of coherent, high-resolution climate change projections and physical models into an economic modeling framework. We find that if the climate of the 2080s were to occur today, the annual loss in household welfare in the European Union (EU) resulting from the four market impacts would range between 0.2-1%. If the welfare loss is assumed to be constant over time, climate change may halve the EU's annual welfare growth. Scenarios with warmer temperatures and a higher rise in sea level result in more severe economic damage. However, the results show that there are large variations across European regions. Southern Europe, the British Isles, and Central Europe North appear most sensitive to climate change. Northern Europe, on the other hand, is the only region with net economic benefits, driven mainly by the positive effects on agriculture. Coastal systems, agriculture, and river flooding are the most important of the four market impacts assessed.


Assuntos
Agricultura/economia , Mudança Climática/economia , Meio Ambiente , Inundações/economia , Modelos Econômicos , Viagem/economia , Simulação por Computador , Europa (Continente) , Medição de Risco
20.
Parasitol Res ; 113(10): 3651-60, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25028211

RESUMO

Teladorsagia circumcincta is among the most important gastrointestinal parasites in small ruminants and the predominant species in Southern European goats. Parasite control is largely based on metaphylactic/preventative treatments, which is often seen as non-sustainable anymore. The reasons are increased consumer demand to reduce chemicals in livestock production and anthelmintic resistance against the common drugs. This study aimed at the development of a T. circumcincta-enzyme-linked immunosorbent assay (ELISA) specifically for goats. Samples were obtained from goats raised parasite-free or infected experimentally. Sampling continued during the following pasture season and housing period. The sensitivity for the use in bulk milk samples as an indicator of T. circumcincta infection levels in grazing goats was examined. The ELISA enables clear differentiation of negative and positive animals. With a specificity of 100% negative cut-off values for serum and milk were 0.294 and 0.228 (sensitivity, 95%). Positive cut-off values (sensitivity, 90%) were 0.606 (serum) and 0.419 (milk), while a sensitivity of 95% resulted in 0.509 and 0.363, respectively. The grey-zone between negative/positive cut-offs was introduced to deal with animals in pre-patency and decreasing antibody levels after infection. There was no cross reactivity for Trichostrongylus colubriformis and Cooperia oncophora while for Haemonchus contortus and Fasciola hepatica it cannot be fully excluded currently. In bulk milk samples, 5% of the milk had to be contributed from animals infected with T. circumcincta to be detected as positive. The results derived from experimentally and naturally infected as well as parasite naïve animals indicate the potential of the ELISA to be used in targeted anthelmintic treatment regimes in goats.


Assuntos
Anticorpos Anti-Helmínticos/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças das Cabras/imunologia , Leite/imunologia , Trichostrongyloidea/imunologia , Tricostrongiloidíase/veterinária , Animais , Anticorpos Anti-Helmínticos/sangue , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/métodos , Fezes/parasitologia , Feminino , Doenças das Cabras/parasitologia , Cabras , Imunoglobulina G/análise , Imunoglobulina G/sangue , Masculino , Contagem de Ovos de Parasitas/veterinária , Trichostrongyloidea/isolamento & purificação , Tricostrongiloidíase/imunologia
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