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BACKGROUND: Xenopus laevis, the African clawed frog, is a versatile vertebrate model organism in various biological disciplines, prominently in developmental biology to study body plan reorganization during metamorphosis. However, a notable gap exists in the availability of comprehensive datasets encompassing Xenopus' late developmental stages. FINDINGS: This study utilized micro-computed tomography (micro-CT), a noninvasive 3-dimensional (3D) imaging technique with micrometer-scale resolution, to explore the developmental dynamics and morphological changes in Xenopus laevis. Our approach involved generating high-resolution images and computed 3D models of developing Xenopus specimens, spanning from premetamorphosis tadpoles to fully mature adults. This dataset enhances our understanding of vertebrate development and supports various analyses. We conducted a careful examination, analyzing body size, shape, and morphological features, focusing on skeletogenesis, teeth, and organs like the brain and gut at different stages. Our analysis yielded valuable insights into 3D morphological changes during Xenopus' development, documenting details previously unrecorded. These datasets hold the solid potential for further morphological and morphometric analyses, including segmentation of hard and soft tissues. CONCLUSIONS: Our repository of micro-CT scans represents a significant resource that can enhance our understanding of Xenopus' development and the associated morphological changes in the future. The widespread utility of this amphibian species, coupled with the exceptional quality of our scans, which encompass a comprehensive series of developmental stages, opens up extensive opportunities for their broader research application. Moreover, these scans can be used in virtual reality, 3D printing, and educational contexts, further expanding their value and impact.
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Imagenología Tridimensional , Microtomografía por Rayos X , Xenopus laevis , Animales , Xenopus laevis/crecimiento & desarrollo , Microtomografía por Rayos X/métodos , Imagenología Tridimensional/métodos , Metamorfosis Biológica , Larva/crecimiento & desarrolloRESUMEN
Chloraluminium phthalocyanine (ClAlPc) has potential therapeutic effect for the treatment of cancer; however, the molecule is lipophilic and may present self-aggregation which limits its clinical success. Thus, nanocarriers like liposomes can improve ClAlPc solubility, reduce off-site toxicity and increase circulation time. For this purpose, developing suitable liposomes requires the evaluation of different lipid compositions. Herein, we aimed to develop liposomes containing soy phosphatidylcholine (SPC), 1,2-distearoyl-sn-glycero- 3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPEPEG2000), cholesterol and oleic acid loaded with ClAlPc using the surface response methodology and the Box-Behnken design. Liposomes with particle size from 110.93 to 374.97 nm and PdI from 0.265 to 0.468 were obtained. The optimized formulation resulted in 69.09 % of ClAlPc encapsulated, with particle size and polydispersity index, respectively, at 153.20 nm and 0.309, providing stability and aggregation control. Atomic force microscopy revealed vesicles in a spherical or almost spherical shape, while the analyzes by Differential Scanning Calorimetry (DSC), Powder X-ray Diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR) suggested that the drug was adequately incorporated into the lipid bilayer of liposomes, in its amorphous state or molecularly dispersed. In vitro studies conducted in breast cancer cells (4T1) showed that liposome improved phototoxicity compared to the ClAlPc solution. ClAlPc-loaded liposomes also enhanced the production of ROS 3-fold compared to the ClAlPc solution. Finally, confocal microscopy and flow cytometry demonstrated the ability of the liposomes to enter cells and deliver the fluorescent ClAlPc photosensitizer with dose and time-dependent effects. Thus, this work showed that Box-Behnken factorial design was an effective strategy for optimizing formulation development. The obtained ClAlPc liposomes can be applied for photodynamic therapy in breast cancer cells.
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Neoplasias de la Mama , Indoles , Liposomas , Compuestos Organometálicos , Tamaño de la Partícula , Fotoquimioterapia , Fármacos Fotosensibilizantes , Fotoquimioterapia/métodos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Indoles/química , Indoles/administración & dosificación , Femenino , Compuestos Organometálicos/química , Compuestos Organometálicos/administración & dosificación , Humanos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/farmacología , Línea Celular Tumoral , Polietilenglicoles/química , Fosfatidiletanolaminas/química , Fosfatidilcolinas/química , Colesterol/química , Ácido Oléico/químicaRESUMEN
Mangroves and saltmarshes are two of the most relevant coastal habitats for humans. These ecosystems offer several services like coastal protection, climate mitigation, and nursery habitats for many artisanal and commercially exploited fish, crabs, and shellfish. They mostly dominate different latitudinal ranges but in several places around the world they co-occur and interact. Here, we summarize the current scientific knowledge on mangrove-saltmarsh ecological interactions and propose a conceptual model. We screened 1410 articles from 1945 to 2022 and selected 29 experiments that assessed mangrove-saltmarsh ecological interactions. Both positive and negative interactions are observed but there is variation along different mangrove life stages. Higher retention and establishment of mangrove propagules are found inside saltmarshes than on bare flats, i.e. facilitation, and these effects are higher at grass than at succulent saltmarsh species. Mangrove seedlings, saplings, or trees mostly compete with saltmarshes, negatively affecting mangrove growth. We propose a model with different outcomes considering the interaction between different mangrove's life stages and saltmarsh forms and discussed these interactions in the light of anthropogenic threats and climate change.
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Ecosistema , Humedales , Animales , Humanos , Poaceae , Plantones , ÁrbolesRESUMEN
Photodynamic therapy (PDT) using methylene blue (MB) as a photosensitizer has emerged as an alternative treatment for skin cancers, such as squamous cell carcinoma (SCC). To increase the cutaneous penetration of the drug, some strategies are used, such as the association of nanocarriers and physical methods. Thus, herein we address the development of nanoparticles based on poly-Æ-caprolactone (PCL), optimized with the Box-Behnken factorial design, for topical application of MB associated with sonophoresis. The MB-nanoparticles were developed using the double emulsification-solvent evaporation technique and the optimized formulation resulted in an average size of 156.93 ± 8.27 nm, a polydispersion index of 0.11 ± 0.05, encapsulation efficiency of 94.22 ± 2.19% and zeta potential of -10.08 ± 1.12 mV. Morphological evaluation by scanning electron microscopy showed spherical nanoparticles. In vitro release studies show an initial burst compatible with the first-order mathematical model. The nanoparticle showed satisfactory generation of reactive oxygen species. The MTT assay was used to assess cytotoxicity and IC50; values of 79.84; 40.46; 22.37; 9.90 µM were obtained, respectively, for the MB-solution and the MB-nanoparticle without and with light irradiation after 2 h of incubation. Analysis using confocal microscopy showed high cellular uptake for the MB-nanoparticle. With regard to skin penetration, a higher concentration of MB was observed in the epidermis + dermis, corresponding to 9.81, 5.27 µg/cm2 in passive penetration and 24.31 and 23.81 µg/cm2 after sonophoresis, for solution-MB and nanoparticle-MB, respectively. To the best of our knowledge, this is the first report of MB encapsulation in PCL nanoparticles for application in skin cancer using PDT.
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Molecular mechanisms surrounding early human embryonic events such as blastocyst formation, implantation, and the specification of the body axes are some of the most attractive research questions of developmental biology today. A knowledge on the detailed signaling landscape underlying these critical events in the human could impact the way we treat early pregnancy disorders and infertility, and considerably advance our abilities to make precise human tissues in a lab. However, owing to ethical, technical, and policy restrictions, research on early human embryo development historically stalled behind animal models. The rapid progress in 3D culture of human embryonic stem cells over the past years created an opportunity to overcome this critical challenge. We review recently developed strategies of making 3D models of the human embryo built from embryonic stem cells, which we refer to as embryoids. We focus on models aimed at reconstituting the 3D epithelial characteristics of the early human embryo, namely the intra/extraembryonic signaling crosstalk, tissue polarity, and embryonic cavities. We identify distinct classes of embryoids based on whether they explicitly include extraembryonic tissues and we argue for the merit of compromising on certain aspects of embryo mimicry in balancing the experimental feasibility with ethical considerations. Human embryoids open gates toward a new field of synthetic human embryology, allowing to study the long inaccessible stages of early human development at unprecedented detail.
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Implantación del Embrión , Desarrollo Embrionario , Embarazo , Animales , Femenino , Humanos , Embrión de Mamíferos , Células Madre EmbrionariasRESUMEN
Wilms tumor-1-interacting protein (Wtip) is a LIM-domain-containing adaptor that links cell junctions with actomyosin complexes and modulates actomyosin contractility and ciliogenesis in Xenopus embryos. The Wtip C-terminus with three LIM domains associates with the actin-binding protein Shroom3 and modulates Shroom3-induced apical constriction in ectoderm cells. By contrast, the N-terminal domain localizes to apical junctions in the ectoderm and basal bodies in skin multiciliated cells, but its interacting partners remain largely unknown. Targeted proximity biotinylation (TPB) using anti-GFP antibody fused to the biotin ligase BirA identified SSX2IP as a candidate protein that binds GFP-WtipN. SSX2IP, also known as Msd1 or ADIP, is a component of cell junctions, centriolar satellite protein and a targeting factor for ciliary membrane proteins. WtipN physically associated with SSX2IP and the two proteins readily formed mixed aggregates in overexpressing cells. By contrast, we observed only partial colocalization of full length Wtip and SSX2IP, suggesting that Wtip adopts a 'closed' conformation in the cell. Furthermore, the double depletion of Wtip and SSX2IP in early embryos uncovered the functional interaction of the two proteins during neural tube closure. Our results suggest that the association of SSX2IP and Wtip is essential for cell junction remodeling and morphogenetic processes that accompany neurulation. We propose that TPB can be a general approach that is applicable to other GFP-tagged proteins.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas del Citoesqueleto/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Factores de Transcripción/metabolismo , Proteínas de Xenopus/metabolismo , Animales , Biotinilación , Espectrometría de Masas , Unión Proteica , Xenopus laevisRESUMEN
The Wnt pathway activates target genes by controlling the ß-catenin-T-cell factor (TCF) transcriptional complex during embryonic development and cancer. This pathway can be potentiated by R-spondins, a family of proteins that bind RNF43/ZNRF3 E3 ubiquitin ligases and LGR4/5 receptors to prevent Frizzled degradation. Here we demonstrate that, during Xenopus anteroposterior axis specification, Rspo2 functions as a Wnt antagonist, both morphologically and at the level of gene targets and pathway mediators. Unexpectedly, the binding to RNF43/ZNRF3 and LGR4/5 was not required for the Wnt inhibitory activity. Moreover, Rspo2 did not influence Dishevelled phosphorylation in response to Wnt ligands, suggesting that Frizzled activity is not affected. Further analysis indicated that the Wnt antagonism is due to the inhibitory effect of Rspo2 on TCF3/TCF7L1 phosphorylation that normally leads to target gene activation. Consistent with this mechanism, Rspo2 anteriorizing activity has been rescued in TCF3-depleted embryos. These observations suggest that Rspo2 is a context-specific regulator of TCF3 phosphorylation and Wnt signaling.
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Tipificación del Cuerpo/efectos de los fármacos , Péptidos y Proteínas de Señalización Intercelular/fisiología , Factor de Transcripción 3/antagonistas & inhibidores , Vía de Señalización Wnt/efectos de los fármacos , Proteínas de Xenopus/antagonistas & inhibidores , Proteínas de Xenopus/fisiología , Animales , Tipificación del Cuerpo/fisiología , Embrión no Mamífero/anomalías , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/metabolismo , Desarrollo Embrionario/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Genes Reporteros , Cabeza/embriología , Fosforilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Factor de Transcripción 3/metabolismo , Proteínas de Xenopus/biosíntesis , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Proteínas de Xenopus/farmacología , Xenopus laevis/embriologíaRESUMEN
Olfactory ensheathing cells (OECs) are specialized glial cells of the olfactory system, believed to play a role in the continuous production of olfactory neurons and ensheathment of their axons. Although OECs are used in therapeutic applications, little is known about the cellular mechanisms underlying their migratory behavior. Recently, we showed that OEC migration is sensitive to ganglioside blockage through A2B5 and Jones antibody in OEC culture. Gangliosides are common components of lipid rafts, where they participate in several cellular mechanisms, including cell migration. Here, we characterized OEC lipid rafts, analyzing the presence of specific proteins and gangliosides that are commonly expressed in motile neural cells, such as young neurons, oligodendrocyte progenitors, and glioma cells. Our results showed that lipid rafts isolated from OECs were enriched in cholesterol, sphingolipids, phosphatidylcholine, caveolin-1, flotillin-1, gangliosides GM1 and 9-O-acetyl GD3, A2B5-recognized gangliosides, CNPase, α-actinin, and ß1-integrin. Analysis of the actin cytoskeleton of OECs revealed stress fibers, membrane spikes, ruffled membranes and lamellipodia during cell migration, as well as the distribution of α-actinin in membrane projections. This is the first description of α-actinin and flotillin-1 in lipid rafts isolated from OECs and suggests that, together with ß1-integrin and gangliosides, membrane lipid rafts play a role during OEC migration. This study provides new information on the molecular composition of OEC membrane microdomains that can impact on our understanding of the role of OEC lipid rafts under physiological and pathological conditions of the nervous system, including inflammation, hypoxia, aging, neurodegenerative diseases, head trauma, brain tumor, and infection.
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Microdominios de Membrana/metabolismo , Bulbo Olfatorio/citología , 2',3'-Nucleótido Cíclico Fosfodiesterasas/metabolismo , Animales , Biomarcadores/metabolismo , Células Cultivadas , Colesterol/metabolismo , Proteínas del Citoesqueleto/metabolismo , Gangliósidos/metabolismo , Microdominios de Membrana/ultraestructura , Ratas Wistar , Proteínas S100/metabolismoRESUMEN
The epidermal growth factor receptor (EGFR) belongs to the tyrosine kinase receptors family and is present in the epithelial cell membrane. Its endogenous activation occurs through the binding of different endogenous ligands, including the epidermal growth factor (EGF), leading to signaling cascades able to maintain normal cellular functions. Although involved in the development and maintenance of tissues in normal conditions, when EGFR is overexpressed, it stimulates the growth and progression of tumors, resulting in angiogenesis, invasion and metastasis, through some main cascades such as Ras/Raf/MAPK, PIK-3/AKT, PLC-PKC and STAT. Besides, considering the limitations of conventional chemotherapy that result in high toxicity and low tumor specificity, EGFR is currently considered an important target. As a result, several monoclonal antibodies are currently approved for use in cancer treatment, such as cetuximab (CTX), panitumumab, nimotuzumab, necitumumab and others are in clinical trials. Aiming to combine the chemotherapeutic agent toxicity and specific targeting to EGFR overexpressing tumor tissues, two main strategies will be discussed in this review: antibody-drug conjugates (ADCs) and antibody-nanoparticle conjugates (ANCs). Briefly, ADCs consist of antibodies covalently linked through a spacer to the cytotoxic drug. Upon administration, binding to EGFR and endocytosis, ADCs suffer chemical and enzymatic reactions leading to the release and accumulation of the drug. Instead, ANCs consist of nanotechnology-based formulations, such as lipid, polymeric and inorganic nanoparticles able to protect the drug against inactivation, allowing controlled release and also passive accumulation in tumor tissues by the enhanced permeability and retention effect (EPR). Furthermore, ANCs undergo active targeting through EGFR receptor-mediated endocytosis, leading to the formation of lysosomes and drug release into the cytosol. Herein, we will present and discuss some important aspects regarding EGFR structure, its role on internal signaling pathways and downregulation aspects. Then, considering that EGFR is a potential therapeutic target for cancer therapy, the monoclonal antibodies able to target this receptor will be presented and discussed. Finally, ADCs and ANCs state of the art will be reviewed and recent studies and clinical progresses will be highlighted. To the best of our knowledge, this is the first review paper to address specifically the EGFR target and its application on ADCs and ANCs.
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Antineoplásicos , Inmunoconjugados , Nanopartículas , Neoplasias , Preparaciones Farmacéuticas , Receptores ErbB , Neoplasias/tratamiento farmacológicoRESUMEN
This review highlights the work that my research group has been developing, together with international collaborators, during the last decade. Since we were able to establish the Xenopus laevis experimental model in Brazil, we have been focused on understanding early embryonic patterns regarding neural induction and axes establishment. In this context, the Wnt pathway appears as a major player and has been much explored by us and other research groups. Here, we chose to review three published works which we consider to be landmarks within the course of our research and also within the history of modern findings regarding neural induction and patterning. We intend to show how our series of discoveries, when painted together, tells a story that covers crucial developmental windows of early differentiation paths of anterior neural tissue: 1. establishing the head organizer in contrast to the trunk organizer in the early gastrula; 2. deciding between neural ectoderm and epidermis ectoderm at the blastula/gastrula stages, and 3. the gathering of prechordal unique properties in the late gastrula/early neurula.
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Tipificación del Cuerpo , Vía de Señalización Wnt , Animales , Ectodermo/metabolismo , Inducción Embrionaria , Gástrula/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Xenopus/genética , Xenopus laevis/metabolismoRESUMEN
Wnt signaling through the Frizzled (FZD) family of serpentine receptors is essential for embryogenesis and homeostasis, and stringent control of the FZD protein level is critical for stem cell regulation. Through CRISPR/Cas9 genome-wide screening in human cells, we identified TMEM79/MATTRIN, an orphan multi-span transmembrane protein, as a specific inhibitor of Wnt/FZD signaling. TMEM79 interacts with FZD during biogenesis and promotes FZD degradation independent of ZNRF3/RNF43 ubiquitin ligases (R-spondin receptors). TMEM79 interacts with ubiquitin-specific protease 8 (USP8), whose activating mutations underlie human tumorigenesis. TMEM79 specifically inhibits USP8 deubiquitination of FZD, thereby governing USP8 substrate specificity and promoting FZD degradation. Tmem79 and Usp8 genes have a pre-bilaterian origin, and Tmem79 inhibition of Usp8 and Wnt signaling is required for anterior neural development and gastrulation in Xenopus embryos. TMEM79 is a predisposition gene for Atopic dermatitis, suggesting deregulation of Wnt/FZD signaling a possible cause for this most common yet enigmatic inflammatory skin disease.
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Desarrollo Embrionario/fisiología , Receptores Frizzled/metabolismo , Proteínas de la Membrana/metabolismo , Xenopus laevis/embriología , Animales , Desarrollo Embrionario/genética , Receptores Frizzled/genética , Células HEK293 , Humanos , Proteínas de la Membrana/genética , Vía de Señalización Wnt/genética , Xenopus laevis/genéticaRESUMEN
Tropical saltmarshes' role as a refuge for macrofauna is poorly known. We tested the hypotheses that: i) there is an increase in abundance of early life-stages of fiddler crabs associated with an increase in vegetation density (thermal and/or predation refuge) and ii) predation are lower within saltmarsh vegetation. The abundance of early life-stages increased with both vegetation density and temperature. Megalopa and juveniles might be adapted or benefit from high temperatures found on tropical saltmarshes and thus do not need protection from it. Predation was higher in saltmarshes than in nearby non-vegetated areas, thus tropical saltmarshes can not be considered a refuge from relatively large predators for juveniles of fiddler crabs. Although not offering refuge against temperature and predation, tropical saltmarshes are important habitats for the recruitment of early life-stages of fiddler crabs. Future studies should consider the evaluation of tropical saltmarsh hydrodynamics in the settlement and permanence of juveniles.
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Braquiuros , Animales , Ecosistema , Conducta Predatoria , TemperaturaRESUMEN
mTOR, a serine/threonine protein kinase that is involved in a series of critical cellular processes, can be found in two functionally distinct complexes, mTORC1 and mTORC2. In contrast to mTORC1, little is known about the mechanisms that regulate mTORC2. Here we show that mTORC2 activity is reduced in mice with a hypomorphic mutation of the Ric-8B gene. Ric-8B is a highly conserved protein that acts as a non-canonical guanine nucleotide exchange factor (GEF) for heterotrimeric Gαs/olf type subunits. We found that Ric-8B hypomorph embryos are smaller than their wild type littermates, fail to close the neural tube in the cephalic region and die during mid-embryogenesis. Comparative transcriptome analysis revealed that signaling pathways involving GPCRs and G proteins are dysregulated in the Ric-8B mutant embryos. Interestingly, this analysis also revealed an unexpected impairment of the mTOR signaling pathway. Phosphorylation of Akt at Ser473 is downregulated in the Ric-8B mutant embryos, indicating a decreased activity of mTORC2. Knockdown of the endogenous Ric-8B gene in cultured cell lines leads to reduced phosphorylation levels of Akt (Ser473), further supporting the involvement of Ric-8B in mTORC2 activity. Our results reveal a crucial role for Ric-8B in development and provide novel insights into the signals that regulate mTORC2.
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Factores de Intercambio de Guanina Nucleótido/genética , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo , Animales , Células Cultivadas , Regulación hacia Abajo/genética , Embrión de Mamíferos , Desarrollo Embrionario/genética , Femenino , Eliminación de Gen , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/genéticaRESUMEN
Notwithstanding impacts of marine debris on fauna by ingestion and suffocation, little is known about debris-related behavior. Lytechinus variegatus is a common sea urchin known for its covering behavior. We hypothesized that L. variegatus would select more marine debris (i.e. litter) than natural material as cover and we also expected that the selected natural and artificial material would be different in weight, sizes and transparency. We haphazardly collected marine debris and natural material on 20 individuals of L. variegatus and on the bottom, around each individual. All sampled material was weighed, measured and classified regarding opacity, nature (natural or artificial). Our results showed that i) sea urchins picked more litter than natural objects, ii) proportional weight of litter carried by urchins was significantly larger than expected by chance, iii) when considering all objects (on urchins and on the bottom) litter was heavier, wider and less opaque than natural material and iv) litter carried by the urchins were wider and less opaque than natural material. We suggest that litter can influence urchin's protection against sunlight, camouflage and ballast and that sea urchins with covering behavior might be used as indicators of marine debris in coastal and deep waters.
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Lytechinus , Erizos de Mar , AnimalesRESUMEN
R-spondins are a family of secreted proteins that play important roles in embryonic development and cancer. R-spondins have been shown to modulate the Wnt pathway; however, their involvement in other developmental signaling processes have remained largely unstudied. Here, we describe a novel function of Rspo2 in FGF pathway regulation in vivo Overexpressed Rspo2 inhibited elongation of Xenopus ectoderm explants and Erk1 activation in response to FGF. By contrast, the constitutively active form of Mek1 stimulated Erk1 even in the presence of Rspo2, suggesting that Rspo2 functions upstream of Mek1. The observed inhibition of FGF signaling was accompanied by the downregulation of the FGF target genes tbxt/brachyury and cdx4, which mediate anterioposterior axis specification. Importantly, these target genes were upregulated in Rspo2-depleted explants. The FGF inhibitory activity was mapped to the thrombospondin type 1 region, contrasting the known function of the Furin-like domains in Wnt signaling. Further domain analysis revealed an unexpected intramolecular interaction that might control Rspo2 signaling output. We conclude that, in addition to its role in Wnt signaling, Rspo2 acts as an FGF antagonist during mesoderm formation and patterning.
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Tipificación del Cuerpo/genética , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Mesodermo/embriología , Mesodermo/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriología , Xenopus laevis/metabolismo , Animales , Regulación hacia Abajo/genética , Ectodermo/embriología , Ectodermo/metabolismo , Factor 2 de Crecimiento de Fibroblastos/farmacología , Gastrulación/genética , Regulación del Desarrollo de la Expresión Génica , Péptidos y Proteínas de Señalización Intercelular , Mutagénesis Sitio-Dirigida/métodos , Dominios Proteicos , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Transducción de Señal/genética , Vía de Señalización Wnt/genética , Proteínas de Xenopus/genética , Xenopus laevis/genéticaRESUMEN
The deregulation of the Wnt/ß-catenin signaling pathway is a central event in colorectal cancer progression, thus a promising target for drug development. Many natural compounds, such as flavonoids, have been described as Wnt/ß-catenin inhibitors and consequently modulate important biological processes like inflammation, redox balance, cancer promotion and progress, as well as cancer cell death. In this context, we identified the chalcone lonchocarpin isolated from Lonchocarpus sericeus as a Wnt/ß-catenin pathway inhibitor, both in vitro and in vivo. Lonchocarpin impairs ß-catenin nuclear localization and also inhibits the constitutively active form of TCF4, dnTCF4-VP16. Xenopus laevis embryology assays suggest that lonchocarpin acts at the transcriptional level. Additionally, we described lonchocarpin inhibitory effects on cell migration and cell proliferation on HCT116, SW480, and DLD-1 colorectal cancer cell lines, without any detectable effects on the non-tumoral intestinal cell line IEC-6. Moreover, lonchocarpin reduces tumor proliferation on the colorectal cancer AOM/DSS mice model. Taken together, our results support lonchocarpin as a novel Wnt/ß-catenin inhibitor compound that impairs colorectal cancer cell growth in vitro and in vivo.
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The use of Xenopus laevis as a model for vertebrate developmental biology is limited by a lack of antibodies specific for embryonic antigens. This study evaluated the use of immune and non-immune phage display libraries for the isolation of single domain antibodies, or nanobodies, with specificities for Xenopus embryonic antigens. The immune nanobody library was derived from peripheral blood lymphocyte RNA obtained from a llama immunized with Xenopus gastrula homogenates. Screening this library by immunostaining of embryonic tissues with pooled periplasmic material and sib-selection led to the isolation of several monoclonal phages reactive with the cytoplasm and nuclei of gastrula cells. One antigen recognized by a group of nanobodies was identified using a reverse proteomics approach as nucleoplasmin, an abundant histone chaperone. As an alternative strategy, a semi-synthetic non-immune llama nanobody phage display library was panned on highly purified Xenopus proteins. This proof-of-principle approach isolated monoclonal nanobodies that specifically bind Nuclear distribution element-like 1 (Ndel1) in multiple immunoassays. Our results suggest that immune and non-immune phage display screens on crude and purified embryonic antigens can efficiently identify nanobodies useful to the Xenopus developmental biology community.
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Desarrollo Embrionario/inmunología , Anticuerpos de Dominio Único/inmunología , Anticuerpos de Dominio Único/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Anticuerpos/aislamiento & purificación , Anticuerpos/metabolismo , Antígenos/inmunología , Técnicas de Visualización de Superficie Celular/métodos , Proteínas del Citoesqueleto/inmunología , Gástrula , Biblioteca de Péptidos , Antígenos Embrionarios Específico de Estadio/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/inmunología , Xenopus laevis/embriología , Xenopus laevis/inmunología , Xenopus laevis/metabolismoRESUMEN
Este artigo apresenta um ensaio poético-fotográfico sobre o Laboratório Sensorial, um dispositivo do projeto de extensão universitária Expressão e Transformação, vinculado ao Instituto de Psicologia da Universidade Federal do Rio de Janeiro, Brasil (UFRJ). Inspirado na Fenomenologia e na Arte Contemporânea, o laboratório é uma proposta de sensibilização corporal que busca desnaturalizar a percepção e os modos cotidianos automatizados de estar no mundo. Os participantes são convidados a vendar os olhos e a serem conduzidos por um percurso de estimulações sensoriais no qual experimentam texturas, odores e sonoridades em temporalidades distintas das do cotidiano. Em seguida, registram suas experiências em mapas corporais. Nas diversas edições realizadas, percebemos que a experiência vivida expande a percepção de si e do outro, avivando uma potência poética de expressão e memória do corpo. Originada na Psicologia Clínica, esta proposta dialoga com outras disciplinas e linguagens, articulando as dimensões ética, estética e política da existência.(AU)
This article presents a poetic photo-essay about the Sensory Laboratory, a facility of the extension project Expression and Transformation attached to the Institute of Psychology at the Federal University of Rio de Janeiro, Brazil (UFRJ). Inspired by Phenomenology and Contemporary Art, the laboratory is a proposal for body awareness aimed at denaturalizing perception and automated everyday modes of being in the world. Participants are invited to wear a blindfold and conducted through a series of sensory stimulations where they experience different textures, odors, and sounds in temporalities that are different to those of everyday life. Their experiences are then depicted in body maps. The findings show that the participants' experiences expand self and other-awareness, vivifying a poetic power of expression and body memories. Originating from Clinical Psychology, this proposal converges towards other disciplines and languages, articulating ethical, aesthetic, political, and existential dimensions.(AU)
Este artículo presenta un ensayo poético-fotográfico sobre el Laboratorio Sensorial, un dispositivo del proyecto de extensión universitaria Expresión y Transformación, vinculado al Instituto de Psicología de la de la Universidad Federal de Rio de Janeiro, Brasil (UFRJ). Inspirado en la Fenomenología y en el Arte Contemporáneo, el laboratorio es una propuesta de sensibilización corporal que busca desnaturalizar la percepción y los modos cotidianos automatizados de estar en el mundo. Los participantes son invitados a vendar los ojos y a ser conducidos por un recorrido de estímulos sensoriales en el cual experimentan texturas, olores y sonidos en temporalidades diferentes de las del cotidiano. A continuación, registran sus experiencias en mapas corporales. En las diversas ediciones realizadas, percibimos que la experiencia vivida expande la percepción de sí mismo y del otro, avivando una potencia poética de expresión y memoria del cuerpo. Originada en la Psicología Clínica, esta propuesta dialoga con otras disciplinas y lenguajes, articulando las dimensiones ética, estética y política de la existencia.(AU)
RESUMEN
O pai e a mãe têm uma importância fundamental no desenvolvimento psicossocial dos filhos, bem como na regulação das emoções. Na pesquisa objetivou-se investigar o manejo dos pais frente à expressão da emoção raiva dos filhos do sexo masculino e feminino. Participaram 26 casais tendo dois filhos de seis a doze anos. Para coleta dos dados, utilizou-se questionário de dados gerais, Critério de Classificação Econômica Brasil, entrevista estruturada e história-estímulo. Verificou-se que as estratégias mais utilizadas pelos pais e mães frente à raiva dos filhos foram reação centrada no problema e reação punitiva, respectivamente estratégias, adaptativa e desadaptativa. Tanto os pais quanto as mães tenderam a reagir com minimização maior com o filho e reagir com distração maior com a filha. Conclui-se que pais e mães utilizam-se das mesmas estratégias mediante à expressão de raiva dos filhos de ambos os sexos, porém, há diferenças de gênero quanto à prática parental. (AU)
The father and the mother have a fundamental importance in the psychosocial development of children, as well as in the regulation of emotions. The objective of this research was to investigate the management of parents in the face of the expression of anger in male and female children. A total of 26 couples participated in the research, including couples that have two children from six to 12 years old. For data collection we used a general data questionnaire, the Brazilian Economic Classification Criteria, a structured interview, and a story-stimulus. We verified that the strategies most used by parents against their children's anger were problem-centered reactions and punitive reactions, respectively adaptive and maladaptive strategies. Both fathers and mothers tended to react with a greater minimization with the son and more distractedly with the daughter. It is concluded that fathers and mothers use the same strategies for both sexes against their children's anger expressions, but there are some gender differences in parental practice. (AU)
Los padres tienen una importancia fundamental en el desarrollo psicosocial de los hijos, así como en la regulación de las emociones. Se buscó investigar el manejo de los padres frente a la expresión de emoción de rabia de los hijos de ambos sexos. Participaron 26 parejas con dos hijos de seis a doce años. Para recolección de datos, se utilizó un cuestionario de datos generales, Criterio de Clasificación Económica Brasil, entrevista estructurada e historia-estímulo. Se verificó que las estrategias más utilizadas por los padres frente a la rabia de los hijos fueron; reacción centrada en el problema y reacción punitiva del problema; respectivamente, estrategias adaptativas y desadaptativas. Tanto la madre como el padre tienden a reaccionar con minimizacion mayor para el hijo y con más distracción con la hija. Conclusión: los padres utilizan las mismas estrategias mediante la expresión de rabia de los hijos, pero hay diferencias de género en cuanto a la práctica parental. (AU)