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1.
Nano Lett ; 22(15): 6454-6461, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35792810

RESUMO

A recent addition to the toolbox of super-resolution microscopy methods is fluorescence-lifetime single-molecule localization microscopy (FL-SMLM). The synergy of SMLM and fluorescence-lifetime imaging microscopy (FLIM) combines superior image resolution with lifetime information and can be realized using two complementary experimental approaches: confocal-laser scanning microscopy (CLSM) or wide-field microscopy. Here, we systematically and comprehensively compare these two novel FL-SMLM approaches in different spectral regions. For wide-field FL-SMLM, we use a commercial lifetime camera, and for CLSM-based FL-SMLM we employ a home-built system equipped with a rapid scan unit and a single-photon detector. We characterize the performances of the two systems in localizing single emitters in 3D by combining FL-SMLM with metal-induced energy transfer (MIET) for localization along the third dimension and in the lifetime-based multiplexed bioimaging using DNA-PAINT. Finally, we discuss advantages and disadvantages of wide-field and confocal FL-SMLM and provide practical advice on rational FL-SMLM experiment design.


Assuntos
DNA , Imagem Individual de Molécula , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Nanotecnologia , Imagem Individual de Molécula/métodos
2.
Clin Immunol ; 238: 109025, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35487454

RESUMO

BACKGROUND: The cell surface molecule CD6 is a modulator of T cell receptor (TCR) signaling. Recently, it has been reported that CD6 is downregulated on CD4+ T cells following T cell activation. This mechanism could limit the efficacy of anti-CD6 therapeutical antibodies. METHODS: We analyzed CD6 expression on activated and non-activated Th1 cells and Th17 cells by flow cytometry. RESULTS: Our experiments confirmed a significant downregulation of CD6 on IFNγ- and IL17-negative CD4+ T cells from healthy individuals and from patients with rheumatoid arthritis following T cell activation with anti-CD3 and anti-CD28 antibodies. In contrast, CD6 expression remained stable on activated Th17 cells and Th1 cells. CONCLUSIONS: Th1 and Th17 cells are resistant towards T cell activation-induced downregulation of CD6. These findings are relevant for the future development of CD6 targeting therapies and show that CD6 expression is differentially regulated in CD4+ T cell subsets.


Assuntos
Antígenos CD , Antígenos de Diferenciação de Linfócitos T , Regulação para Baixo , Ativação Linfocitária , Células Th1 , Células Th17 , Antígenos CD28/metabolismo , Humanos
3.
Cell Mol Life Sci ; 79(1): 3, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34913099

RESUMO

Autoimmune arthritis is characterized by impaired regulatory T (Treg) cell migration into inflamed joint tissue and by dysregulation of the balance between Treg cells and Th17 cells. Interleukin-6 (IL-6) is known to contribute to this dysregulation, but the molecular mechanisms behind impaired Treg cell migration remain largely unknown. In this study, we assessed dynamic changes in membrane-bound IL-6 receptor (IL6R) expression levels on Th17 cells by flow cytometry during the development of collagen-induced arthritis (CIA). In a next step, bioinformatics analysis based on proteomics was performed to evaluate potential pathways affected by altered IL-6R signaling in autoimmune arthritis. Our analysis shows that membrane-bound IL-6R is upregulated on Th17 cells and is inversely correlated with IL-6 serum levels in experimental autoimmune arthritis. Moreover, IL-6R expression is significantly increased on Th17 cells from untreated patients with rheumatoid arthritis (RA). Interestingly, CD4+ T cells from CIA mice and RA patients show reduced phosphorylation of vasodilator-stimulated phosphoprotein (VASP). Bioinformatics analysis based on proteomics of CD4+ T cells with low or high phosphorylation levels of VASP revealed that integrin signaling and related pathways are significantly enriched in cells with low phosphorylation of VASP. Specific inhibition of p-VASP reduces the migratory function of Treg cells but has no influence on effector CD4+ T cells. Importantly, IL-6R blockade restores the phosphorylation level of VASP, thereby improving the migratory function of Treg cells from RA patients. Thus, our results establish a link between IL6R signaling and phosphorylation of VASP, which controls Treg cell migration in autoimmune arthritis.


Assuntos
Artrite Reumatoide/patologia , Moléculas de Adesão Celular/metabolismo , Proteínas dos Microfilamentos/metabolismo , Fosfoproteínas/metabolismo , Receptores de Interleucina-6/metabolismo , Linfócitos T Reguladores/metabolismo , Células Th17/metabolismo , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Artrite Reumatoide/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Movimento Celular , Humanos , Interleucina-6/sangue , Camundongos , Camundongos Endogâmicos DBA , Fosforilação , Linfócitos T Reguladores/citologia , Células Th17/citologia , Regulação para Cima
4.
J Phys Chem A ; 124(17): 3494-3500, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32255633

RESUMO

Fluorescence lifetime imaging (FLIM) has become an important microscopy technique in bioimaging. The two most important of its applications are lifetime-multiplexing for imaging many different structures in parallel, and lifetime-based measurements of Förster resonance energy transfer. There are two principal FLIM techniques, one based on confocal-laser scanning microscopy (CLSM) and time-correlated single-photon counting (TCSPC) and the other based on wide-field microscopy and phase fluorometry. Although the first approach (CLSM-TCSPC) assures high sensitivity and allows one to detect single molecules, it is slow and has a small photon yield. The second allows, in principal, high frame rates (by 2-3 orders of magnitude faster than CLSM), but it suffers from low sensitivity, which precludes its application for single-molecule imaging. Here, we demonstrate that a novel wide-field TCSPC camera (LINCam25, Photonscore GmbH) can be successfully used for single-molecule FLIM, although its quantum yield of detection in the red spectral region is only ∼5%. This is due to the virtually absent background and readout noise of the camera, assuring high signal-to-noise ratio even at low detection efficiency. We performed single-molecule FLIM of different red fluorophores, and we use the lifetime information for successfully distinguishing between different molecular species. Finally, we demonstrate single-molecule metal-induced energy transfer (MIET) imaging which is a first step for three-dimensional single-molecule localization microscopy (SMLM) with nanometer resolution.


Assuntos
Imagem Óptica/métodos , Imagem Individual de Molécula/métodos , Razão Sinal-Ruído
5.
Methods ; 140-141: 32-39, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29454862

RESUMO

This chapter presents a concise introduction into the method of Fluorescence Lifetime Correlation Spectroscopy (FLCS). This is an extension of Fluorescence Correlation Spectroscopy (FCS) that analyses fluorescence intensity fluctuations from small detection volumes in samples of ultra-low concentration. FCS has been widely used for investigating diffusion, conformational changes, molecular binding/unbinding equilibria, or chemical reaction kinetics, at single molecule sensitivity. In FCS, this is done by calculating intensity correlation curves for the measured intensity fluctuations. FLCS extends this idea by calculating fluorescence-lifetime specific intensity correlation curves. Thus, FLCS is the method of choice for all studies where a parameter of interest (conformational state, spatial position, molecular environmental condition) is connected with a change in the fluorescence lifetime. After presenting the theoretical and experimental basis of FLCS, the chapter gives an overview of its various applications.


Assuntos
Fluorescência , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Difusão , Cinética , Conformação Molecular , Espectrometria de Fluorescência/instrumentação , Fatores de Tempo
6.
Microsurgery ; 38(6): 634-642, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29603352

RESUMO

PURPOSE: Facial paralysis has a profound impact on functionality and esthetics of the oral region. In patients with strong skin laxity and soft tissue ptosis, functional smile reconstruction is challenging due to the accentuated asymmetry at rest. Thus, the purpose of the study was to analyze facial symmetry in this patient clientele following a combination of dynamic reanimation with fascial strips for static suspension compared to functional gracilis transfer alone. METHODS: In 2014, we altered the single-stage approach for microsurgical smile reconstruction in patients with significant soft tissue ptosis by adding fascia lata grafts for static support. We evaluated 6 patients (mean age 57.8 ± 5.2, group A) who underwent the combined procedure, and compared their results to 6 patients with flaccid facial paralysis who were treated before 2014 and received a functional gracilis transfer alone (mean age 52.5 ± 7.5, group B). To test the efficacy of the technique, we retrospectively analyzed the correction of the oral asymmetry as well as nasal and philtral deviation by computer-assisted photograph analysis 6 months postoperatively. RESULTS: The comparative analysis revealed a significant postoperative improvement of the oral asymmetry (A: 90.0 ± 5.0% relative correction at rest vs. B: 62.6 ± 17.2%, P < .05), nasal (A: 0.4 ± 0.2 vs. B: 0.7 ± 0.4 mm, P < .05), and philtral deviation (A: 0.5 ± 0.6 vs. B: 2.8 ± 1.8 mm, P < .05) in group A. CONCLUSIONS: The combined procedure for dynamic facial reanimation allows for immediate correction of the oral asymmetry and improves overall outcome in patients with advanced soft tissue ptosis and oral asymmetry at rest.


Assuntos
Paralisia Facial/cirurgia , Fascia Lata/transplante , Músculo Grácil/transplante , Microcirurgia , Procedimentos de Cirurgia Plástica/métodos , Sorriso , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Resultado do Tratamento
7.
Appl Opt ; 55(6): 1241-8, 2016 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-26906574

RESUMO

We have used a plane wave expansion method to theoretically study the far-field head-media optical interaction in heat-assisted magnetic recording. For the Advanced Storage Technology Consortium media stack specifically, we notice the outstanding sensitivity related to the interlayer's optical thickness for media reflection and the magnetic layer's light absorption. With 10 nm interlayer thickness change, the recording layer absorption can be changed by more than 25%. The 2D results are found to correlate well with the full 3D model and magnetic recording tests on a flyable disc with different interlayer thickness.

8.
Circulation ; 130(1): 35-50, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24982116

RESUMO

BACKGROUND: The relevance of the dissociation of circulating pentameric C-reactive protein (pCRP) to its monomeric subunits (mCRP) is poorly understood. We investigated the role of conformational C-reactive protein changes in vivo. METHODS AND RESULTS: We identified mCRP in inflamed human striated muscle, human atherosclerotic plaque, and infarcted myocardium (rat and human) and its colocalization with inflammatory cells, which suggests a general causal role of mCRP in inflammation. This was confirmed in rat intravital microscopy of lipopolysaccharide-induced cremasteric muscle inflammation. Intravenous pCRP administration significantly enhanced leukocyte rolling, adhesion, and transmigration via localized dissociation to mCRP in inflamed but not noninflamed cremaster muscle. This was confirmed in a rat model of myocardial infarction. Mechanistically, this process was dependent on exposure of lysophosphatidylcholine on activated cell membranes, which is generated after phospholipase A2 activation. These membrane changes could be visualized intravitally on endothelial cells, as could the colocalized mCRP generation. Blocking of phospholipase A2 abrogated C-reactive protein dissociation and thereby blunted the proinflammatory effects of C-reactive protein. Identifying the dissociation process as a therapeutic target, we stabilized pCRP using 1,6-bis(phosphocholine)-hexane, which prevented dissociation in vitro and in vivo and consequently inhibited the generation and proinflammatory activity of mCRP; notably, it also inhibited mCRP deposition and inflammation in rat myocardial infarction. CONCLUSIONS: These results provide in vivo evidence for a novel mechanism that localizes and aggravates inflammation via phospholipase A2-dependent dissociation of circulating pCRP to mCRP. mCRP is proposed as a pathogenic factor in atherosclerosis and myocardial infarction. Most importantly, the inhibition of pCRP dissociation represents a promising, novel anti-inflammatory therapeutic strategy.


Assuntos
Proteína C-Reativa/química , Proteínas de Transporte/química , Inflamação/metabolismo , Músculo Esquelético/metabolismo , Infarto do Miocárdio/metabolismo , Miosite/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Biopolímeros , Proteína C-Reativa/fisiologia , Proteínas de Transporte/fisiologia , Adesão Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Quimiotaxia de Leucócito , Ativação do Complemento , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Hexanos/farmacologia , Hexanos/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Inflamação/etiologia , Migração e Rolagem de Leucócitos/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Lisofosfatidilcolinas/metabolismo , Masculino , Lipídeos de Membrana/metabolismo , Músculo Esquelético/irrigação sanguínea , Infarto do Miocárdio/patologia , Miosite/induzido quimicamente , Miosite/patologia , Inibidores de Fosfolipase A2/farmacologia , Inibidores de Fosfolipase A2/uso terapêutico , Fosfolipases A2/metabolismo , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacologia , Fosforilcolina/uso terapêutico , Estrutura Quaternária de Proteína , Distribuição Aleatória , Ratos , Ratos Wistar , Receptores de IgG/fisiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia
9.
Basic Res Cardiol ; 110(3): 32, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25916938

RESUMO

The inflammatory sequelae of ischemia-reperfusion injury (IRI) are a major causal factor of tissue injury in various clinical settings. MicroRNAs (miRs) are short, non-coding RNAs, which regulate protein expression. Here, we investigated the role of miR-155 in IR-related tissue injury. Quantifying microRNA-expression levels in a human muscle tissue after IRI, we found miR-155 expression to be significantly increased and to correlate with the increased expression of TNF-α, IL-1ß, CD105, and Caspase3 as well as with leukocyte infiltration. The direct miR-155 target gene SOCS-1 was downregulated. In a mouse model of myocardial infarction, temporary LAD ligation and reperfusion injury resulted in a smaller area of necrosis in miR-155-/- animals compared to wildtype animals. To investigate the underlying mechanisms, we evaluated the effect of miR-155 on inflammatory cell recruitment by intravital microscopy and on the generation of reactive oxygen species (ROS) of macrophages. Our intravital imaging results demonstrated a decreased recruitment of inflammatory cells in miR-155-/- animals during IRI. The generation of ROS in leukocytic cells of miR-155-/- animals was also reduced. RNA silencing of the direct miR-155 target gene SOCS-1 abrogated this effect. In conclusion, miR-155 aggravates the inflammatory response, leukocyte infiltration and tissue damage in IRI via modulation of SOCS-1-dependent generation of ROS. MiR-155 is thus a potential target for the treatment or prevention of IRI.


Assuntos
Quimiotaxia de Leucócito/fisiologia , Inflamação/metabolismo , MicroRNAs/metabolismo , Traumatismo por Reperfusão/metabolismo , Migração Transendotelial e Transepitelial/fisiologia , Animais , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Humanos , Inflamação/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real , Traumatismo por Reperfusão/genética , Explosão Respiratória/fisiologia , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Transfecção
10.
Int Immunol ; 26(8): 467-78, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24844702

RESUMO

Tissue damage in burn injury leads to a rapid increase of leukocytes and acute phase reactants. Plasma levels of C-reactive protein (CRP) rise within hours after the insult. No deficiency of this protein has been reported in humans, suggesting it plays a pivotal role in innate immunity. CRP in circulation is composed of five identical subunits [pentameric CRP (pCRP)]. Recently, deposits of structurally modified CRP (mCRP) have been found in inflammatory diseases. Little is known about this structural change and how it affects CRP functions. We analyzed CRP deposits in burn wounds and serum by immunohistochemistry, western blot and dot blot analysis. CRP was deposited in necrotic and inflamed tissue, but not in adjacent healthy tissue. Tissue deposited CRP was detected by mCRP-specific antibodies and structurally different from serum pCRP. mCRP but not pCRP induced reactive oxygen species production by monocytes and facilitated uptake of necrotic Jurkat cells by macrophages. In addition, it accelerated migration of keratinocytes in a scratch wound assay. The structural changes that occur in pCRP upon localization to damaged and inflamed tissue in burn wounds result in a functionally altered protein with distinct functions. mCRP exhibits opsonic, proinflammatory and promigratory properties which modulate wound healing.


Assuntos
Queimaduras/metabolismo , Proteína C-Reativa/química , Proteína C-Reativa/metabolismo , Apoptose , Queimaduras/imunologia , Queimaduras/patologia , Linhagem Celular , Movimento Celular , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Queratinócitos/imunologia , Queratinócitos/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Fagocitose/imunologia , Conformação Proteica , Espécies Reativas de Oxigênio/metabolismo , Pele/imunologia , Pele/metabolismo , Pele/patologia , Cicatrização
11.
Oecologia ; 177(2): 441-52, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25380645

RESUMO

It is well known that pathogens and arthropod herbivores attacking the same host plant may affect each other. Little is known, however, about their combined impact on plant fitness, which may differ from simple additive expectations. In a 2-year common garden field experiment, we tested whether the pathogen Albugo sp. (white blister rust) and the herbivorous flea beetle Phyllotreta nemorum affected each other's performance on two resistance types (G-type and P-type) of the crucifer Barbarea vulgaris ssp. arcuata, and whether biomass, reproduction and survival of the plants were affected by interactive impacts of the antagonists. Most of the insect-resistant G-plants were severely affected by white rust, which reduced biomass and reproductive potential compared to the controls. However, when also exposed to flea beetles, biomass loss was mitigated in G-plants, even though apparent disease symptoms were not reduced. Most of the insect-susceptible P-plants were resistant to white rust; however, the number of flea beetle mines tended to increase in plants also exposed to Albugo, and biomass at the last harvest was slightly lower in the combined treatment. Thus, interactive impacts of the herbivore and pathogen differed between the two resistance types, with an antagonistic combined impact in G-plants, which lasted surprisingly long, and a slight synergistic impact in P-plants.


Assuntos
Barbarea/microbiologia , Besouros/microbiologia , Herbivoria , Oomicetos/fisiologia , Animais , Barbarea/genética , Resistência à Doença , Doenças das Plantas/microbiologia
12.
Physiol Rep ; 11(19): e15829, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37771106

RESUMO

The JAK/STAT pathway plays a crucial role in the pathogenesis of rheumatoid arthritis (RA) and JAK inhibitors have emerged as a new group of effective drugs for RA treatment. Recently, high STAT3 levels have been associated with the upregulation of the scaffold protein NEDD9, which is a regulator of T-cell trafficking and promotes collagen-induced arthritis (CIA). In this study, we aimed to reveal how treatment with JAK inhibitors affects NEDD9 in CD4+ T cells from RA patients. We analyzed NEDD9 expression in CD4+ T cells from 50 patients treated with either baricitinib, tofacitinib, or upadacitinib and performed cell migration assays to assess the potential influence of JAK inhibitor treatment on CD4+ T-cell migration. We observed that treatment with baricitinib and upadacitinib is associated with reduced NEDD9 expression in CD4+ T cells. In contrast, NEDD9 levels were not altered during treatment with tofacitinib. Moreover, treatment with baricitinib was associated with a significantly reduced migratory capacity of effector CD4+ T cells but not with impaired migration of Treg cells. This study reveals previously unknown associations between JAK inhibitor treatment and NEDD9 expression and indicates that JAK inhibitors could reduce effector T-cell migration.


Assuntos
Artrite Reumatoide , Inibidores de Janus Quinases , Humanos , Inibidores de Janus Quinases/farmacologia , Inibidores de Janus Quinases/uso terapêutico , Janus Quinases , Linfócitos T CD4-Positivos/patologia , Transdução de Sinais , Fatores de Transcrição STAT , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Proteínas Adaptadoras de Transdução de Sinal
13.
Nat Ecol Evol ; 7(2): 236-249, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36376602

RESUMO

The impact of local biodiversity loss on ecosystem functioning is well established, but the role of larger-scale biodiversity dynamics in the delivery of ecosystem services remains poorly understood. Here we address this gap using a comprehensive dataset describing the supply of 16 cultural, regulating and provisioning ecosystem services in 150 European agricultural grassland plots, and detailed multi-scale data on land use and plant diversity. After controlling for land-use and abiotic factors, we show that both plot-level and surrounding plant diversity play an important role in the supply of cultural and aboveground regulating ecosystem services. In contrast, provisioning and belowground regulating ecosystem services are more strongly driven by field-level management and abiotic factors. Structural equation models revealed that surrounding plant diversity promotes ecosystem services both directly, probably by fostering the spill-over of ecosystem service providers from surrounding areas, and indirectly, by maintaining plot-level diversity. By influencing the ecosystem services that local stakeholders prioritized, biodiversity at different scales was also shown to positively influence a wide range of stakeholder groups. These results provide a comprehensive picture of which ecosystem services rely most strongly on biodiversity, and the respective scales of biodiversity that drive these services. This key information is required for the upscaling of biodiversity-ecosystem service relationships, and the informed management of biodiversity within agricultural landscapes.


Assuntos
Biodiversidade , Ecossistema , Agricultura/métodos , Plantas
14.
Biodivers Data J ; 10: e83523, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36761658

RESUMO

Background: The decline of pollinating insects in agricultural landscapes proceeds due to intensive land use and the associated loss of habitat and food sources. The feeding of those insects depends on the spatial and temporal distribution of nectar and pollen as food resource. Hence, to protect insect biodiversity, a spatio-temporal assessment of food quantity of their habitats is necessary. Therefore, sufficient data on traits of floral resources are required. New information: As floral resources' traits of plants are important to quantify food availability, we present two databases, the FloRes Database (Floral Resources Database) and the raw database, from where FloRes was derived. Both databases contain the plant traits: (1) flowering period, (2) floral-unit density per day, (3) nectar volume per floral unit per day, (4) sugar content per floral unit, (5) sugar concentration in nectar, (6) pollen mass or volume per floral unit and per day, (7) protein content of pollen and (8) corolla depth. All traits were sampled from literature and online databases. The raw database consists of 702 specified plant species, 138 unspecified species 37 species (spec., sp), 22 species pluralis (spp) and, for 79, only the genus was identified) and two species complexes (agg.). Those 842 taxa belong to 488 genera and 102 families. Finally, only 27 taxa have a complete set of traits, too few for a sufficient assessment of spatio-temporal availability of floral food-resources.As information on floral resources is scattered throughout many publications with different units, we also present our multistep workflow implemented in five consecutive R-scripts. The multistep workflow standardises the trait units of the raw database to comparable entities with identical units and aggregates them on a reasonable taxonomic level into the second application database, the FloRes Database. Finally, the FloRes Database contains aggregated information of traits for 42 taxa and, when corolla depth is excluded, for 72 taxa.This is the first attempt to gather these eight traits from different literature sources into one database with a multistep workflow. The publication of the multistep workflow enables the users to extend the FloRes Database on their own demands with other literature data or newly-gathered data to improve quantification of food resources. Especially, the combination of pollen, nectar and the open flowers per square metre is, as far as we know, a novelty.The FloRes Database can be used to evaluate the quantity of food-resource habitats available for pollinators, for example, to compare seed mixtures of agri-environmental measures, such as flower strips, considering flower phenology on a daily basis.

15.
RMD Open ; 8(2)2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36216409

RESUMO

BACKGROUND: Several health authorities recommend a third (booster) vaccination to protect patients with rheumatic and musculoskeletal diseases from severe COVID-19. Methotrexate has been shown to reduce the efficacy of the first and second dose of SARS-CoV-2 mRNA vaccines. So far, it remains unknown how concomitant methotrexate affects the efficacy of a COVID-19 booster vaccination. METHODS: We compared the humoral immune response to SARS-CoV-2 vaccination in 136 patients with rheumatoid arthritis (RA) treated with methotrexate and/or biological or targeted synthetic (b/tsDMARDs). IgG targeting the receptor binding domain (RBD) of SARS-CoV-2 spike protein was measured at a median of 52.5 (range 2-147) days after a third dose of the SARS-CoV-2 mRNA vaccines BNT162b2 or mRNA-1273. RESULTS: Anti-RBD IgG was significantly reduced in elderly patients receiving concomitant treatment with methotrexate as compared with elderly patients receiving monotherapy with b/tsDMARDs or methotrexate (64.8 (20.8, 600.3) binding antibody units per mL (BAU/mL) vs 1106.0 (526.3, 4965.2) BAU/mL vs 1743.8 (734.5, 6779.6) BAU/mL, median (IQR), p<0.001, Kruskal-Wallis test). In younger patients (< 64.5 years), concomitant methotrexate had no significant impact on the humoral immune response. CONCLUSIONS: Concomitant methotrexate increases the risk of an insufficient humoral immune response to SARS-CoV-2 vaccination in elderly patients with RA. Pausing methotrexate during the third vaccination period may be considered for this group of patients.


Assuntos
Artrite Reumatoide , Vacinas contra COVID-19 , COVID-19 , Imunidade Humoral , Metotrexato , Idoso , Anticorpos Antivirais , Artrite Reumatoide/tratamento farmacológico , Vacina BNT162 , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Humanos , Imunoglobulina G , Metotrexato/uso terapêutico , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
16.
Commun Biol ; 5(1): 38, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35017652

RESUMO

DNA point accumulation for imaging in nanoscale topography (DNA-PAINT) is a powerful super-resolution technique highly suitable for multi-target (multiplexing) bio-imaging. However, multiplexed imaging of cells is still challenging due to the dense and sticky environment inside a cell. Here, we combine fluorescence lifetime imaging microscopy (FLIM) with DNA-PAINT and use the lifetime information as a multiplexing parameter for targets identification. In contrast to Exchange-PAINT, fluorescence lifetime PAINT (FL-PAINT) can image multiple targets simultaneously and does not require any fluid exchange, thus leaving the sample undisturbed and making the use of flow chambers/microfluidic systems unnecessary. We demonstrate the potential of FL-PAINT by simultaneous imaging of up to three targets in a cell using both wide-field FLIM and 3D time-resolved confocal laser scanning microscopy (CLSM). FL-PAINT can be readily combined with other existing techniques of multiplexed imaging and is therefore a perfect candidate for high-throughput multi-target bio-imaging.


Assuntos
DNA/química , Microscopia de Fluorescência/métodos , Imagem Molecular/métodos , Nanotecnologia/métodos , DNA/análise , Corantes Fluorescentes/química , Células HeLa , Humanos , Microscopia Confocal
17.
Lupus Sci Med ; 9(1)2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35940821

RESUMO

OBJECTIVE: SLE is an autoimmune disease with a complex pathogenesis. T-cell infiltration into organs contributes to inflammation and organ damage in SLE. Recently, G-protein signalling modulator 2 (GPSM2) has been shown to be implicated in T-cell migration. METHODS: We analysed the expression levels of GPSM2 and of a truncated isoform of GPSM2 containing the GoLoco motif region in CD4+ T cells from patients with SLE and from healthy individuals by western blot. In a next step, we studied the role of the truncated GPSM2 isoform using a CD4+ T-cell migration assay. RESULTS: Our experiments revealed comparable levels of GPSM2 in CD4+ T cells from patients with SLE and healthy controls. In contrast, the truncated 35 kDa isoform of GPSM2 was significantly more highly expressed in CD4+ T cells from patients with SLE as compared with healthy subjects. Antibody-mediated blockade of the 35 kDa GPSM2 isoform reduced the in vitro capacity of CD4+ T cells to migrate towards the chemokine CCL20. CONCLUSIONS: A truncated GPSM2 isoform containing the GoLoco motif region is upregulated in CD4+ T cells from patients with SLE and promotes CD4+ T-cell migration. Targeting this isoform with specific antibodies might be a promising approach to reduce CD4+ T-cell infiltration into inflamed tissues and to prevent organ damage in SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Linfócitos T CD4-Positivos/metabolismo , Movimento Celular , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Isoformas de Proteínas/metabolismo , Linfócitos T
18.
Sci Adv ; 8(23): eabo2506, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35675401

RESUMO

Over the past two decades, super-resolution microscopy has seen a tremendous development in speed and resolution, but for most of its methods, there exists a remarkable gap between lateral and axial resolution, which is by a factor of 2 to 3 worse. One recently developed method to close this gap is metal-induced energy transfer (MIET) imaging, which achieves an axial resolution down to nanometers. It exploits the distance-dependent quenching of fluorescence when a fluorescent molecule is brought close to a metal surface. In the present manuscript, we combine the extreme axial resolution of MIET imaging with the extraordinary lateral resolution of single-molecule localization microscopy, in particular with direct stochastic optical reconstruction microscopy (dSTORM). This combination allows us to achieve isotropic three-dimensional super-resolution imaging of subcellular structures. Moreover, we used spectral demixing for implementing dual-color MIET-dSTORM that allows us to image and colocalize, in three dimensions, two different cellular structures simultaneously.

19.
Front Bioinform ; 1: 740281, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36303750

RESUMO

Fluorescence-lifetime single molecule localization microscopy (FL-SMLM) adds the lifetime dimension to the spatial super-resolution provided by SMLM. Independent of intensity and spectrum, this lifetime information can be used, for example, to quantify the energy transfer efficiency in Förster Resonance Energy Transfer (FRET) imaging, to probe the local environment with dyes that change their lifetime in an environment-sensitive manner, or to achieve image multiplexing by using dyes with different lifetimes. We present a thorough theoretical analysis of fluorescence-lifetime determination in the context of FL-SMLM and compare different lifetime-fitting approaches. In particular, we investigate the impact of background and noise, and give clear guidelines for procedures that are optimized for FL-SMLM. We do also present and discuss our public-domain software package "Fluorescence-Lifetime TrackNTrace," which converts recorded fluorescence microscopy movies into super-resolved FL-SMLM images.

20.
Nat Commun ; 12(1): 3918, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34168127

RESUMO

Land-use intensification is a major driver of biodiversity loss. However, understanding how different components of land use drive biodiversity loss requires the investigation of multiple trophic levels across spatial scales. Using data from 150 agricultural grasslands in central Europe, we assess the influence of multiple components of local- and landscape-level land use on more than 4,000 above- and belowground taxa, spanning 20 trophic groups. Plot-level land-use intensity is strongly and negatively associated with aboveground trophic groups, but positively or not associated with belowground trophic groups. Meanwhile, both above- and belowground trophic groups respond to landscape-level land use, but to different drivers: aboveground diversity of grasslands is promoted by diverse surrounding land-cover, while belowground diversity is positively related to a high permanent forest cover in the surrounding landscape. These results highlight a role of landscape-level land use in shaping belowground communities, and suggest that revised agroecosystem management strategies are needed to conserve whole-ecosystem biodiversity.


Assuntos
Biodiversidade , Ecossistema , Plantas , Microbiologia do Solo , Agricultura , Animais , Europa (Continente) , Cadeia Alimentar , Florestas , Pradaria , Herbivoria , Insetos
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