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1.
Sci Total Environ ; 929: 172431, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38663616

RESUMO

Recent advancements in spatial modelling leverage remote sensing data and statistical species-environment relationships to forecast the distribution of a specific species. Our study focuses on Disko Bay in West Greenland, recognized as a significant marine biodiversity hotspot in the region. We conducted comprehensive analyses using multiple datasets spanning from 2010 to 2019, incorporating shrimp and fish surveys, commercial shrimp fishery catches, high-resolution (25 × 25 m) multibeam bathymetry and backscatter data along with a medium-resolution (200 × 200 m) bathymetric model, measured and modelled oceanographic data, and satellite chlorophyll data. Through multivariate regression analysis, we tested the significance of various physical factors (seafloor depth, sediment class, bottom water temperature, bottom water salinity, bottom current velocity, space, and time), biological factors (chlorophyll a, Greenland halibut (Reinhardtius hippoglossoides)), and anthropogenic impact (shrimp fishery; standardized catch per unit effort) on the density of northern shrimp in the area. Our results indicate a significant association between northern shrimp density, seafloor depth, and sediment class, explaining 36 % of the variation in shrimp density. Subsequently, we developed a high-resolution (optimized) spatial linear mixed-effect model to map the distribution of northern shrimp across Disko Bay, representing the first model of its kind developed for an Arctic area. The optimal habitat for northern shrimp is characterized by medium-deep waters (approximately 150-350 m), turbulent conditions, and mixed sediments, predominantly located in the northern and southern regions of Disko Bay. Notably, the northern region hosts a relatively diverse benthic community, with northern shrimp and sponges as the primary contributors of epibenthic biomass. This novel high-resolution model significantly enhances our understanding of the physical drivers and detailed spatial patterns influencing the distribution of northern shrimp in the Arctic.


Assuntos
Baías , Ecossistema , Pandalidae , Animais , Groenlândia , Monitoramento Ambiental , Biodiversidade , Regiões Árticas , Pesqueiros
2.
Plants (Basel) ; 12(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37653863

RESUMO

Here we report the medium-term effects of foliar spray and endo-therapy treatments with different doses of a Cu/Zn citric acid biocomplex (Dentamet®) in Xylella fastidiosa infected olive trees of Salento, Apulia region (South-east Italy). Leaf extract samples from field-treated 150 years old olive trees cvs Ogliarola salentina and Cellina di Nardò were studied by 1H NMR-based metabolomics. The result of different applications of Dentamet® endo-therapy after 60, 120 and 180 days in comparison with traditional foliar spray treatment and water injection as a control have been investigated. The metabolic profile analyses, performed by 1H NMR-based metabolomic approach, indicated plant metabolites variations connected to the disease progression such as mannitol, quinic acid, and oleuropein related compounds. The best results, in terms of discrimination of the metabolic profiles with respect to water injection, were found for monthly endo-therapy treatments. Dentamet® foliar application demonstrated more specific time related progressive effectiveness with respect to intravascular treatments. Therefore, besides a possible more effective performance of endo-therapy with respect to foliar treatments, the need of further doses/frequencies trimming to obtain long-term results was also assessed. The present field studies confirmed the indication of Dentamet® effectiveness in metabolic variation induction, potentially linked with reducing the X. fastidiosa subspecies pauca related Olive Quick Decline Syndrome (OQDS) symptoms development.

3.
Sci Rep ; 12(1): 5973, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35396514

RESUMO

Xylella fastidiosa is a xylem-limited bacterium causing a range of economically important plant diseases in hundreds of crops. Over the last decade, a severe threat due to Olive Quick Decline Syndrome (OQDS), caused by Xylella fastidiosa subspecies pauca, affected the Salento olive groves (Apulia, South-East Italy). Very few phyto-therapeutics, including a Zn/Cu citric acid biocomplex foliar treatment, were evaluated to mitigate this disease. However, the traditional foliar applications result in the agro-actives reaching only partially their target. Therefore the development of novel endo-therapeutic systems was suggested. Metabolite fingerprinting is a powerful method for monitoring both, disease progression and treatment effects on the plant metabolism, allowing biomarkers detection. We performed, for the first time, short-term monitoring of metabolic pathways reprogramming for infected Ogliarola salentina and Cima di Melfi olive trees after precision intravascular biocomplex delivery using a novel injection system. Upon endo therapy, we observed specific variations in the leaf content of some metabolites. In particular, the 1H NMR-based metabolomics approach showed, after the injection, a significant decrease of both the disease biomarker quinic acid and mannitol with simultaneous increase of polyphenols and oleuropein related compounds in the leaf's extracts. This combined metabolomics/endo-therapeutic methodology provided useful information in the comprehension of plant physiology for future applications in OQDS control.


Assuntos
Metabolômica , Olea , Xylella , Metabolômica/métodos , Olea/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Espectroscopia de Prótons por Ressonância Magnética/métodos , Xylella/metabolismo
4.
ISME J ; 16(4): 1012-1024, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34764454

RESUMO

Biological soil crusts (biocrusts) release the reactive nitrogen gases (Nr) nitrous acid (HONO) and nitric oxide (NO) into the atmosphere, but the underlying microbial process controls have not yet been resolved. In this study, we analyzed the activity of microbial consortia relevant in Nr emissions during desiccation using transcriptome and proteome profiling and fluorescence in situ hybridization. We observed that < 30 min after wetting, genes encoding for all relevant nitrogen (N) cycling processes were expressed. The most abundant transcriptionally active N-transforming microorganisms in the investigated biocrusts were affiliated with Rhodobacteraceae, Enterobacteriaceae, and Pseudomonadaceae within the Alpha- and Gammaproteobacteria. Upon desiccation, the nitrite (NO2-) content of the biocrusts increased significantly, which was not the case when microbial activity was inhibited. Our results confirm that NO2- is the key precursor for biocrust emissions of HONO and NO. This NO2- accumulation likely involves two processes related to the transition from oxygen-limited to oxic conditions in the course of desiccation: (i) a differential regulation of the expression of denitrification genes; and (ii) a physiological response of ammonia-oxidizing organisms to changing oxygen conditions. Thus, our findings suggest that the activity of N-cycling microorganisms determines the process rates and overall quantity of Nr emissions.


Assuntos
Ácido Nitroso , Solo , Hibridização in Situ Fluorescente , Óxido Nítrico , Nitrogênio/análise , Dióxido de Nitrogênio , Ácido Nitroso/metabolismo , Óxido Nitroso/análise , Oxigênio , Microbiologia do Solo , Água/metabolismo
5.
Sci Rep ; 11(1): 10633, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-34017032

RESUMO

The feeding biology of deep-sea octocorals remains poorly understood, as attention is more often directed to reef building corals. The present study focused on two common deep-water octocoral species in the Azores Archipelago, Dentomuricea aff. meteor and Viminella flagellum, aiming at determining their ability to exploit different food sources. We adopted an experimental approach, with three different food sources, including live phytoplankton, live zooplankton and dissolved organic matter (DOM), that were artificially enriched with 13C and 15N (C and N tracers). The presence of tracers was subsequently followed in the coral tissue, C respiration and particulate organic C and N (POC and PON) release. In both species, feeding with zooplankton resulted in significantly higher incorporation of tracers in all measured variables, compared to the other food sources, highlighting the importance of zooplankton for major physiological processes. Our results revealed contrasting metabolic strategies between the two species, with D. aff. meteor acquiring higher amounts of prey and allocating higher percentage to respiration and release of POC and PON than V. flagellum. Such metabolic differences can shape species fitness and distributions and have further ecological implications on the ecosystem function of communities formed by different octocoral species.


Assuntos
Antozoários/metabolismo , Oceanos e Mares , Animais , Carbono/análise , Modelos Biológicos , Nitrogênio/análise , Consumo de Oxigênio
6.
Radiat Oncol ; 15(1): 189, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32758252

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is an extremely challenging disease with a high mortality rate and a short overall survival time. The poor prognosis can be explained by aggressive tumor growth, late diagnosis, and therapy resistance. Consistent efforts have been made focusing on early tumor detection and novel drug development. Various strategies aim at increasing target specificity or local enrichment of chemotherapeutics as well as imaging agents in tumor tissue. Aptamers have the potential to provide early detection and permit anti-cancer therapy with significantly reduced side effects. These molecules are in-vitro selected single-stranded oligonucleotides that form stable three-dimensional structures. They are capable of binding to a variety of molecular targets with high affinity and specificity. Several properties such as high binding affinity, the in vitro chemical process of selection, a variety of chemical modifications of molecular platforms for diverse function, non-immunoreactivity, modification of bioavailability, and manipulation of pharmacokinetics make aptamers attractive targets compared to conventional cell-specific ligands. To explore the potential of aptamers for early diagnosis and targeted therapy of PDAC - as single agents and in combination with radiotherapy - we summarize the generation process of aptamers and their application as biosensors, biomarker detection tools, targeted imaging tracers, and drug-delivery carriers. We are furthermore discussing the current implementation aptamers in clinical trials, their limitations and possible future utilization.


Assuntos
Antineoplásicos/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Terapia de Alvo Molecular , Neoplasias Pancreáticas/tratamento farmacológico , Medicina de Precisão , Humanos , Técnica de Seleção de Aptâmeros
7.
Phys Rev Lett ; 124(4): 043902, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32058792

RESUMO

Time-varying metasurfaces are emerging as a powerful instrument for the dynamical control of the electromagnetic properties of a propagating wave. Here we demonstrate an efficient time-varying metasurface based on plasmonic nano-antennas strongly coupled to an epsilon-near-zero (ENZ) deeply subwavelength film. The plasmonic resonance of the metal resonators strongly interacts with the optical ENZ modes, providing a Rabi level spitting of ∼30%. Optical pumping at frequency ω induces a nonlinear polarization oscillating at 2ω responsible for an efficient generation of a phase conjugate and a negative refracted beam with a conversion efficiency that is more than 4 orders of magnitude greater compared to the bare ENZ film. The introduction of a strongly coupled plasmonic system therefore provides a simple and effective route towards the implementation of ENZ physics at the nanoscale.

8.
Chirurg ; 91(4): 307-312, 2020 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-31965200

RESUMO

Fournier's gangrene is a special form of necrotizing soft tissue infection (NSTI) and can affect the genital, perineal and perianal regions. Although the disease is named after Fournier, it was first documented by Baurienne in 1764. He described it as idiopathic rapidly progressive gangrene in young otherwise healthy men. Nowadays, the disease is more likely to affect older patients, especially those with pre-existing diseases (e.g. diabetes mellitus and peripheral arterial occlusive disease). Although men are still predominantly affected by Fournier's gangrene, by definition it can also affect women. In most cases it is caused by polymicrobial infections with Enterobacteriaceae. The less common monomicrobial infections are frequently caused by beta hemolyzing Streptococci and then frequently in connection with toxic shock syndrome. Early and aggressive surgical and antimicrobial treatment is crucial to reduce mortality and morbidity. The indications for surgical exploration must be generously considered. The calculated antimicrobial treatment should be carried out as soon as possible, intravenously and in a sufficiently high dosage to catch the expected pathogen. In the era of overspecialization, the treatment of Fournier's gangrene remains a competence that must be comprehensively mastered by clinically active surgeons and urologists. Little has changed with respect to the diagnostic and treatment algorithms in recent years; nevertheless, based on the abovenamed aspects it would appear to be meaningful to present the current aspects and treatment of the disease.


Assuntos
Fasciite Necrosante , Gangrena de Fournier , Desbridamento , Feminino , Gangrena , Humanos , Masculino , Períneo
9.
Chirurg ; 91(4): 301-306, 2020 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-31834420

RESUMO

Necrotizing fasciitis (NF) is a disease of a group of entities with an aggressive course summarized under the term necrotizing skin and soft-tissue infections (NSTI). It is a life-threatening and often disabling infection and is primarily clinically diagnosed. Initially, clinical signs of infection can be insidious and confounded by absence of fever and typical cutaneous lesions. The later course is characterized by soft tissue lesions, excessive pain and systemic toxicity. As the infection can spread rapidly, and as a delay in treatment is associated with increased mortality, additional diagnostic imaging should be confined to a minimum. Prompt and radical surgical debridement (including repeated debridement after 24 h) is a prerequisite for survival in NF. Also, prompt administration of high-dose broad-spectrum antibiotics and a differentiated intensive treatment are necessary. The role of immunoglobulins and hyperbaric oxygenation remains controversial, therefore, the routine use of these measures cannot be recommended at the moment. Close interdisciplinary collaboration is required in order to optimize the treatment and to save life and limb of patients suffering from this life-threatening infection.


Assuntos
Fasciite Necrosante , Oxigenoterapia Hiperbárica , Infecções dos Tecidos Moles/terapia , Antibacterianos/uso terapêutico , Desbridamento , Humanos
11.
Nat Commun ; 10(1): 5119, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712619

RESUMO

Unique structural and optical properties of atomically thin two-dimensional semiconducting transition metal dichalcogenides enable in principle their efficient coupling to photonic cavities having the optical mode volume close to or below the diffraction limit. Recently, it has become possible to make all-dielectric nano-cavities with reduced mode volumes and negligible non-radiative losses. Here, we realise low-loss high-refractive-index dielectric gallium phosphide (GaP) nano-antennas with small mode volumes coupled to atomic mono- and bilayers of WSe[Formula: see text]. We observe a photoluminescence enhancement exceeding 10[Formula: see text] compared with WSe[Formula: see text] placed on planar GaP, and trace its origin to a combination of enhancement of the spontaneous emission rate, favourable modification of the photoluminescence directionality and enhanced optical excitation efficiency. A further effect of the coupling is observed in the photoluminescence polarisation dependence and in the Raman scattering signal enhancement exceeding 10[Formula: see text]. Our findings reveal dielectric nano-antennas as a promising platform for engineering light-matter coupling in two-dimensional semiconductors.

12.
Neurologia (Engl Ed) ; 34(4): 234-240, 2019 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28318732

RESUMO

INTRODUCTION: Given that epileptic seizures and non-epileptic paroxysmal events have similar clinical manifestations, using specific diagnostic methods is crucial, especially in patients with drug-resistant epilepsy. Prolonged video electroencephalography monitoring during epileptic seizures reveals epileptiform discharges and has become an essential procedure for epilepsy diagnosis. The main purpose of this study is to characterise paroxysmal events and compare patterns in patients with refractory epilepsy. METHODS: We conducted a retrospective analysis of medical records from 91 patients diagnosed with refractory epilepsy who underwent prolonged video electroencephalography monitoring during hospitalisation. RESULTS: During prolonged video electroencephalography monitoring, 76.9% of the patients (n=70) had paroxysmal events. The mean number of events was 3.4±2.7; the duration of these events was highly variable. Most patients (80%) experienced seizures during wakefulness. The most common events were focal seizures with altered levels of consciousness, progressive bilateral generalized seizures and psychogenic non-epileptic seizures. Regarding all paroxysmal events, no differences were observed in the number or type of events by sex, in duration by sex or age at onset, or in the number of events by type of event. Psychogenic nonepileptic seizures were predominantly registered during wakefulness, lasted longer, started at older ages, and were more frequent in women. CONCLUSIONS: Paroxysmal events recorded during prolonged video electroencephalography monitoring in patients with refractory epilepsy show similar patterns and characteristics to those reported in other latitudes.


Assuntos
Epilepsia Resistente a Medicamentos/diagnóstico , Eletroencefalografia/métodos , Diagnóstico Diferencial , Epilepsia Resistente a Medicamentos/fisiopatologia , Feminino , Humanos , Masculino , Monitorização Fisiológica/métodos , Estudos Retrospectivos , Gravação em Vídeo , Adulto Jovem
13.
Eat Weight Disord ; 24(6): 1155-1164, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29397562

RESUMO

BACKGROUND: Intimacy is a key psychological problem in anorexia nervosa (AN). Empirical evidence, including neurobiological underpinnings, is however, scarce. OBJECTIVE: In this study, we evaluated various emotional stimuli including intimate stimuli experienced in patients with AN and non-patients, as well as their cerebral response. METHODS: Functional magnetic resonance imaging was conducted using stimuli with positive, neutral, negative and intimate content. Participants (14 AN patients and 14 non-patients) alternated between passive viewing and explicit emotion regulation. RESULTS: Intimate stimuli were experienced less positively in AN patients compared to non-patients. AN patients showed decreased cerebral responses in superior parietal cortices in response to positive and intimate stimuli. Intimate stimuli led to stronger activation of the orbitofrontal cortex, and lower activation of the bilateral precuneus in AN patients. Orbitofrontal responses decreased in AN patients during explicit emotion regulation. CONCLUSIONS: These results show that intimate stimuli are of particular importance in AN patients, who show experiential differences compared to non-patients and altered activation of orbitofrontal and parietal brain structures. This supports that AN patients have difficulties with intimacy, attachment, self-referential processing and body perception. LEVEL OF EVIDENCE: Level III, case-control study.


Assuntos
Anorexia Nervosa/diagnóstico por imagem , Regulação Emocional , Lobo Frontal/diagnóstico por imagem , Relações Interpessoais , Lobo Parietal/diagnóstico por imagem , Anorexia Nervosa/fisiopatologia , Anorexia Nervosa/psicologia , Estudos de Casos e Controles , Emoções , Feminino , Lobo Frontal/fisiopatologia , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Lobo Parietal/fisiopatologia , Adulto Jovem
14.
eNeuro ; 5(1)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29516036

RESUMO

Stress is a potent etiological factor in the onset of major depressive disorder and posttraumatic stress disorder (PTSD). Therefore, significant efforts have been made to identify factors that produce resilience to the outcomes of a later stressor, in hopes of preventing untoward clinical outcomes. The NMDA receptor antagonist ketamine has recently emerged as a prophylactic capable of preventing neurochemical and behavioral outcomes of a future stressor. Despite promising results of preclinical studies performed in male rats, the effects of proactive ketamine in female rats remains unknown. This is alarming given that stress-related disorders affect females at nearly twice the rate of males. Here we explore the prophylactic effects of ketamine on stress-induced anxiety-like behavior and the neural circuit-level processes that mediate these effects in female rats. Ketamine given one week prior to an uncontrollable stressor (inescapable tailshock; IS) reduced typical stress-induced activation of the serotonergic (5-HT) dorsal raphe nucleus (DRN) and eliminated DRN-dependent juvenile social exploration (JSE) deficits 24 h after the stressor. Proactive ketamine altered prelimbic cortex (PL) neural ensembles so that a later experience with IS now activated these cells, which it ordinarily would not. Ketamine acutely activated a PL to DRN (PL-DRN) circuit and inhibition of this circuit with Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) at the time of IS one week later prevented stress prophylaxis, suggesting that persistent changes in PL-DRN circuit activity are responsible, at least in part, for mediating long-term effects associated with ketamine.


Assuntos
Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Ketamina/administração & dosagem , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia , Resiliência Psicológica/efeitos dos fármacos , Estresse Psicológico/prevenção & controle , Animais , Ansiedade/prevenção & controle , Núcleo Dorsal da Rafe/efeitos dos fármacos , Núcleo Dorsal da Rafe/fisiologia , Eletrochoque , Feminino , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Ratos Sprague-Dawley , Serotonina/fisiologia
15.
Acta Neurol Scand ; 137(2): 165-173, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28741711

RESUMO

OBJECTIVES: Methods to evaluate the relative contributions of demyelination vs axonal degeneration over the long-term course of MS are urgently needed. We used magnetic resonance diffusion tensor imaging (DTI) to estimate degrees of demyelination and axonal degeneration in the corpus callosum (CC) in cases of MS with different final outcomes. MATERIALS AND METHODS: We determined DTI measures mean diffusivity (MD), fractional anisotropy (FA), and axial (AD) and radial (RD) diffusivities in the CC of 31 MS patients, of whom 13 presented a secondary progressive course, 11 a non-progressive course, and seven a monophasic course. The study participants were survivors from an incidence cohort of 254 attack-onset MS patients with 50 years of longitudinal follow-up. As reference, we included five healthy individuals without significant morbidity. RESULTS: In patients with secondary progression, compared to all other groups, the corpus callosum showed increased RD and reduced FA, but no change in AD. None of the parameters exhibited differences among non-progressive and monophasic course groups and controls. CONCLUSION: Increased RD was observed in secondary progressive MS, indicating significant myelin loss. Normal RD values observed in the clinically isolated syndrome and non-progressive groups confirm their benign nature. AD was not a characterizing parameter for long-term outcome. Demyelination revealed by increased RD is a distinguishing trait for secondary progression.


Assuntos
Imagem de Tensor de Difusão/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Adulto , Doenças Desmielinizantes/diagnóstico por imagem , Doenças Desmielinizantes/patologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Degeneração Neural/diagnóstico por imagem , Degeneração Neural/patologia
16.
Nano Lett ; 17(12): 7455-7461, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29116805

RESUMO

A core process in many quantum tasks is the generation of entanglement. It is being actively studied in a variety of physical settings-from simple bipartite systems to complex multipartite systems. In this work we experimentally study the generation of bipartite entanglement in a nanophotonic system. Entanglement is generated via the quantum interference of two surface plasmon polaritons in a beamsplitter structure, i.e., utilizing the Hong-Ou-Mandel (HOM) effect, and its presence is verified using quantum state tomography. The amount of entanglement is quantified by the concurrence and we find values of up to 0.77 ± 0.04. Verifying entanglement in the output state from HOM interference is a nontrivial task and cannot be inferred from the visibility alone. The techniques we use to verify entanglement could be applied to other types of photonic system and therefore may be useful for the characterization of a range of different nanophotonic quantum devices.

17.
Nano Lett ; 17(10): 6131-6139, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28933153

RESUMO

To decipher the molecular mechanisms of biological function, it is critical to map the molecular composition of individual cells or even more importantly tissue samples in the context of their biological environment in situ. Immunofluorescence (IF) provides specific labeling for molecular profiling. However, conventional IF methods have finite multiplexing capabilities due to spectral overlap of the fluorophores. Various sequential imaging methods have been developed to circumvent this spectral limit but are not widely adopted due to the common limitation of requiring multirounds of slow (typically over 2 h at room temperature to overnight at 4 °C in practice) immunostaining. We present here a practical and robust method, which we call DNA Exchange Imaging (DEI), for rapid in situ spectrally unlimited multiplexing. This technique overcomes speed restrictions by allowing for single-round immunostaining with DNA-barcoded antibodies, followed by rapid (less than 10 min) buffer exchange of fluorophore-bearing DNA imager strands. The programmability of DEI allows us to apply it to diverse microscopy platforms (with Exchange Confocal, Exchange-SIM, Exchange-STED, and Exchange-PAINT demonstrated here) at multiple desired resolution scales (from ∼300 nm down to sub-20 nm). We optimized and validated the use of DEI in complex biological samples, including primary neuron cultures and tissue sections. These results collectively suggest DNA exchange as a versatile, practical platform for rapid, highly multiplexed in situ imaging, potentially enabling new applications ranging from basic science, to drug discovery, and to clinical pathology.


Assuntos
DNA/química , Hipocampo/citologia , Imunoconjugados/química , Microscopia Confocal/métodos , Neurônios/ultraestrutura , Imagem Óptica/métodos , Mapeamento de Interação de Proteínas/métodos , Animais , Encéfalo/ultraestrutura , Células Cultivadas , Corantes Fluorescentes/química , Hipocampo/ultraestrutura , Camundongos , Microscopia de Fluorescência/métodos , Neurônios/citologia , Retina/citologia , Retina/ultraestrutura , Coloração e Rotulagem/métodos , Sinapsinas/análise , Sinaptofisina/análise
18.
Sci Rep ; 7(1): 12150, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28939861

RESUMO

Signal transduction by receptor tyrosine kinases (RTKs) involves complex ligand- and time-dependent changes in conformation and modification state. High resolution structures are available for individual receptors dimers, but less is known about receptor clusters that form in plasma membranes composed of many different RTKs with the potential to interact. We report the use of multiplexed super-resolution imaging (Exchange-PAINT) followed by mean-shift clustering and random forest analysis to measure the precise distributions of five receptor tyrosine kinases (RTKs) from the ErbB, IGF-1R and Met families in breast cancer cells. We find that these receptors are intermixed nonhomogenously on the plasma membrane. Stimulation by EGF does not appear to induce a change in the density of EGFR in local clusters but instead results in formation of EGFR-Met and EGFR-ErbB3 associations; non-canonical EGFR-Met interactions are implicated in resistance to anti-cancer drugs but have not been previously detected in drug-naïve cells.


Assuntos
Membrana Celular/metabolismo , Imagem Óptica/métodos , Mapas de Interação de Proteínas , Proteínas Proto-Oncogênicas c-met/metabolismo , Animais , Células CHO , Linhagem Celular , Análise por Conglomerados , Cricetulus , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/análise , Receptores ErbB/metabolismo , Humanos , Aprendizado de Máquina , Mapeamento de Interação de Proteínas/métodos , Proteínas Proto-Oncogênicas c-met/análise , Receptor ErbB-3/metabolismo
19.
Nanotechnology ; 28(39): 395501, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-28726674

RESUMO

We report a non-contact CVD graphene gas sensing method that utilises a high Q microwave dielectric resonator perturbation technique. A graphene sample is coupled to the evanescent field of a dielectric resonator whereupon nitrogen dioxide (NO2), a p-doping gas, is detected by monitoring the change in the linewidth and frequency of the resonant mode. The resonant peak shape is dependent on the number of carriers in the graphene sheet. Therefore, the linewidth perturbation can be converted to a measurement of the graphene sheet resistance. To demonstrate the strength of this technique, sensor response curves for NO2 at different concentrations and temperatures are measured showing sub ppm sensitivity. This technique eliminates interactions between the trace gas and metal contacts that otherwise effect the sensor response of the graphene device.

20.
Acta Psychiatr Scand ; 135(6): 573-583, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28407202

RESUMO

OBJECTIVE: White matter (WM) alterations have been reported in children and adults with autism spectrum disorder (ASD). In particular, impaired connectivity of limbic structures may be related to social deficits. Heterogeneous findings could be explained in terms of differences in sample characteristics and methodology. In this context, non-syndromic forms might differ substantially in WM structure from secondary ASD forms. METHOD: In an attempt to recruit a homogeneous study sample, we included adults with high-functioning ASD and an IQ > 100 to decrease the influence of syndromic forms being often associated with cognitive deficits. Diffusion tensor imaging (DTI) was performed in 30 participants with ASD and 30 pairwise-matched controls. Fractional anisotropy (FA) and mean diffusivity (MD) as surrogate imaging markers for WM integrity were calculated. RESULTS: We found a significant FA decrease in the ASD group in the genu and body of the corpus callosum (CC). Increased MD was detected in the subgenual anterior cingulate cortex (sACC). CONCLUSION: The finding of decreased WM integrity in the genu of the CC is in line with earlier studies reporting a decreased number of interhemispheric fibers in the frontal lobe of ASD. Alterations in the sACC might be associated with 'Theory of mind' deficits.


Assuntos
Transtorno do Espectro Autista/patologia , Substância Branca/patologia , Adulto , Anisotropia , Transtorno do Espectro Autista/diagnóstico por imagem , Estudos de Casos e Controles , Corpo Caloso/patologia , Imagem de Tensor de Difusão , Feminino , Giro do Cíngulo/patologia , Humanos , Inteligência , Masculino , Neuroimagem , Substância Branca/diagnóstico por imagem
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