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1.
Colloids Surf B Biointerfaces ; 241: 114039, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38879896

RESUMO

Thin films have been identified as an alternative approach for targeting sensitive site as drug delivery tool. In this work, the preparation of self-rolling thin films to form tubes for wound healing and easy placement (e.g. in the colon via colonoscopy) have been studied. We explored the use of thin films as a protective dressing combined to local release of an anti-inflammatory in order to improve drug efficacy and limit the side effects of the oral route. Non-cytotoxic poly(ethylene) glycol and poly(lactic acid) photo-crosslinkable star copolymers were used for rapid UV crosslinking of bilayered films loaded with prednisolone. The films, crosslinked under UV lamp without the need of photoinitiator, are optimized and compared in terms of water uptake, swelling ratio, final tube diameter and morphology, anti-inflammatory drug loading and release. Our studies showed the spontaneous rolling of bilayer constructs directly after immersion in water. Tubular geometry allows application of the patch through minimally invasive procedures such as colonoscopy. Moreover, the rolled-up bilayers highlighted efficient release of encapsulated drug following Fickian diffusion mechanism. We also confirmed the anti-inflammatory activity of the released anti-inflammatory drug that inhibits the pro-inflammatory cytokine IL-1ß in RAW 264.7 macrophages stimulated by Escherichia coli (E. coli).

2.
Trials ; 24(1): 759, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012776

RESUMO

BACKGROUND: Endometriosis is a chronic disease characterized by growth of endometrial tissue outside the uterine cavity which could affect 200 million women (The term "woman" is used for convenience. Individuals gendered as man or as nonbinary can also suffer from this disease) worldwide. One of the most common symptoms of endometriosis is pelvic chronic pain associated with fatigue. This pain can cause psychological distress and interpersonal difficulties. As for several chronic diseases, adapted physical activity could help to manage the physical and psychological symptoms. The present study will investigate the effects of a videoconference-based adapted physical activity combined with endometriosis-based education program on quality of life, pain, fatigue, and other psychological symptoms and on physical activity. METHODS: This multicentric randomized-controlled trial will propose to 200 patients with endometriosis to be part of a trial which includes a 6-month program with 45 min to more than 120 min a week of adapted physical activity and/or 12 sessions of endometriosis-based education program. Effects of the program will be compared to a control group in which patients will be placed on a waiting list. All participants will be followed up 3 and 6 months after the intervention. None of the participants will be blind to the allocated trial arm. The primary outcome measure will be quality of life. Secondary outcomes will include endometriosis-related perceived pain, fatigue, physical activity, and also self-image, stereotypes, motivational variables, perceived support, kinesiophobia, basic psychological need related to physical activity, and physical activity barriers. General linear models and multilevel models will be performed. Predictor, moderator, and mediator variables will be investigated. DISCUSSION: This study is one of the first trials to test the effects of a combined adapted physical activity and education program for improving endometriosis symptoms and physical activity. The results will help to improve care for patients with endometriosis. TRIAL REGISTRATION: ClinicalTrials.gov, NCT05831735 . Date of registration: April 25, 2023.


Assuntos
Endometriose , Qualidade de Vida , Masculino , Humanos , Feminino , Endometriose/diagnóstico , Endometriose/terapia , Endometriose/complicações , Exercício Físico , Dor Pélvica/etiologia , Fadiga , Comunicação por Videoconferência , Terapia por Exercício/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
3.
Eur J Neurosci ; 36(5): 2588-96, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22748123

RESUMO

Moth sex pheromone communication is recognised as a long-standing model for insect olfaction studies, and a widespread knowledge has been accumulated on this subject thanks to numerous chemical, electrophysiological and behavioural studies. A key step has been the identification of candidate sex pheromone receptors, opening new routes to understanding the specificity and sensitivity of this communication system, but only few of these receptors have as yet been functionally characterised. In this context, we aim at unravelling the molecular bases of pheromone reception in the noctuid moth Spodoptera littoralis. Taking advantage of a collection of antennal-expressed sequence tags, we previously identified three fragments of candidate pheromone receptors in this species. Here, we report full-length cloning of one of these receptors, named SlitOR6. Both sequence and expression pattern analyses were consistent with its annotation as a pheromone receptor, which we further confirmed by functional characterization. Using Drosophila antennae as a heterologous expression system, we identified a single component of the pheromone blend of S. littoralis, (Z,E)-9,12-tetradecadienyl acetate, as the ligand of SlitOR6. Two strategies were employed: (i) expressing SlitOR6 in the majority of Drosophila olfactory neurons, in addition to endogenous receptors, and monitoring the responses to pheromone stimuli by electroantennography; (ii) replacing the Drosophila pheromone receptor OR67d with SlitOR6 and monitoring the response by single sensillum recordings. Results were fully congruent and responses to (Z,E)-9,12-tetradecadienyl acetate were highly specific in both heterologous systems. This approach appears to be efficient and reliable for studying moth pheromone receptors in an in vivo context.


Assuntos
Proteínas de Insetos/metabolismo , Receptores de Feromônios/metabolismo , Potenciais de Ação , Sequência de Aminoácidos , Animais , Antenas de Artrópodes/metabolismo , Antenas de Artrópodes/fisiologia , Drosophila/genética , Drosophila/metabolismo , Drosophila/fisiologia , Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/fisiologia , Dados de Sequência Molecular , Neurônios Receptores Olfatórios/fisiologia , Receptores de Feromônios/genética , Receptores de Feromônios/fisiologia , Sensilas/fisiologia , Atrativos Sexuais/farmacologia , Spodoptera
4.
Plast Reconstr Surg ; 145(3): 542e-551e, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32097311

RESUMO

BACKGROUND: Texturing processes have been designed to improve biocompatibility and mechanical anchoring of breast implants. However, a high degree of texturing has been associated with severe abnormalities. In this study, the authors aimed to determine whether implant surface topography could also affect physiology of asymptomatic capsules. METHODS: The authors collected topographic measurements from 17 different breast implant devices by interferometry and radiographic microtomography. Morphologic structures were analyzed statistically to obtain a robust breast implant surface classification. The authors obtained three topographic categories of textured implants (i.e., "peak and valleys," "open cavities," and "semiopened cavities") based on the cross-sectional aspects. The authors simultaneously collected 31 Baker grade I capsules, sorted them according to the new classification, established their molecular profile, and examined the tissue organization. RESULTS: Each of the categories showed distinct expression patterns of genes associated with the extracellular matrix (Timp and Mmp members) and inflammatory response (Saa1, Tnsf11, and Il8), despite originating from healthy capsules. In addition, slight variations were observed in the organization of capsular tissues at the histologic level. CONCLUSIONS: The authors combined a novel surface implant classification system and gene profiling analysis to show that implant surface topography is a bioactive cue that can trigger gene expression changes in surrounding tissue, even in Baker grade I capsules. The authors' new classification system avoids confusion regarding the word "texture," and could be transposed to implant ranges of every manufacturer. This new classification could prove useful in studies on potential links between specific texturizations and the incidence of certain breast-implant associated complications.


Assuntos
Implante Mamário/efeitos adversos , Implantes de Mama/efeitos adversos , Mama/imunologia , Contratura Capsular em Implantes/imunologia , Complicações Pós-Operatórias/imunologia , Adulto , Idoso , Doenças Assintomáticas , Biomarcadores/análise , Mama/diagnóstico por imagem , Mama/cirurgia , Implante Mamário/instrumentação , Matriz Extracelular/imunologia , Estudos de Viabilidade , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/imunologia , Humanos , Contratura Capsular em Implantes/diagnóstico , Contratura Capsular em Implantes/epidemiologia , Contratura Capsular em Implantes/genética , Incidência , Interferometria , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/genética , Géis de Silicone , Propriedades de Superfície , Microtomografia por Raio-X
5.
Biomaterials ; 234: 119746, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31945617

RESUMO

Cell deformation occurs in many critical biological processes, including cell extravasation during immune response and cancer metastasis. These cells deform the nucleus, their largest and stiffest organelle, while passing through narrow constrictions in vivo and the underlying mechanisms still remain elusive. It is unclear which biochemical actors are responsible and whether the nucleus is pushed or pulled (or both) during deformation. Herein we use an easily-tunable poly-L-lactic acid micropillar topography, mimicking in vivo constrictions to determine the mechanisms responsible for nucleus deformation. Using biochemical tools, we determine that actomyosin contractility, vimentin and nucleo-cytoskeletal connections play essential roles in nuclear deformation, but not A-type lamins. We chemically tune the adhesiveness of the micropillars to show that pulling forces are predominantly responsible for the deformation of the nucleus. We confirm these results using an in silico cell model and propose a comprehensive mechanism for cellular and nuclear deformation during confinement. These results indicate that microstructured biomaterials are extremely versatile tools to understand how forces are exerted in biological systems and can be useful to dissect and mimic complex in vivo behaviour.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Actomiosina , Núcleo Celular , Humanos , Vimentina
6.
Cell Tissue Res ; 335(2): 455-63, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19034524

RESUMO

In insects, biogenic amines have been shown to play an important role in olfactory plasticity. In a first attempt to decipher the underlying molecular mechanisms, we report the molecular cloning and precise expression pattern of a newly identified octopamine/tyramine-receptor-encoding gene in the antennae of the noctuid moth Mamestra brassicae (MbraOAR/TAR). A full-length cDNA has been obtained through homology cloning in combination with rapid amplification of cDNA ends/polymerase chain reaction; the deduced protein exhibits high identities with previously identified octopamine/tyramine receptors in other moths. In situ hybridization within the antennae has revealed that MbraOAR/TAR is expressed at the bases of both pheromone-sensitive and non-sensitive olfactory sensilla and in cells with a neurone-like shape. In accordance with previous physiological studies that have revealed a role of biogenic amines in the electrical activity of the receptor neurones, our results suggest that biogenic amines (either octopamine or tyramine) target olfactory receptor neurones to modulate olfactory coding as early as the antennal level.


Assuntos
Mariposas/metabolismo , Neurônios Receptores Olfatórios/metabolismo , Receptores de Amina Biogênica/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Expressão Gênica/genética , Expressão Gênica/fisiologia , Dados de Sequência Molecular , Mariposas/genética , Neurônios Receptores Olfatórios/citologia , Feromônios/metabolismo , Filogenia , Receptores de Amina Biogênica/classificação , Receptores de Amina Biogênica/genética , Alinhamento de Sequência , Olfato/fisiologia
7.
Nat Commun ; 9(1): 3995, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-30266986

RESUMO

Cells have evolved multiple mechanisms to apprehend and adapt finely to their environment. Here we report a new cellular ability, which we term "curvotaxis" that enables the cells to respond to cell-scale curvature variations, a ubiquitous trait of cellular biotopes. We develop ultra-smooth sinusoidal surfaces presenting modulations of curvature in all directions, and monitor cell behavior on these topographic landscapes. We show that adherent cells avoid convex regions during their migration and position themselves in concave valleys. Live imaging combined with functional analysis shows that curvotaxis relies on a dynamic interplay between the nucleus and the cytoskeleton-the nucleus acting as a mechanical sensor that leads the migrating cell toward concave curvatures. Further analyses show that substratum curvature affects focal adhesions organization and dynamics, nuclear shape, and gene expression. Altogether, this work identifies curvotaxis as a new cellular guiding mechanism and promotes cell-scale curvature as an essential physical cue.


Assuntos
Movimento Celular/fisiologia , Núcleo Celular/fisiologia , Forma Celular/fisiologia , Citoesqueleto/fisiologia , Animais , Adesão Celular/genética , Adesão Celular/fisiologia , Linhagem Celular , Movimento Celular/genética , Forma Celular/genética , Expressão Gênica , Humanos , Camundongos , Microscopia Confocal , Modelos Biológicos , Propriedades de Superfície , Imagem com Lapso de Tempo/métodos
8.
Acta Biomater ; 55: 481-492, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28434979

RESUMO

Design of new osteoinductive biomaterials to reproduce an optimized physiological environment capable of recruiting stem cells and instructing their fate towards the osteoblastic lineage has become a priority in orthopaedic surgery. This work aims at evaluating the bioactivity of BMP combined with human plasma fibronectin (FN/BMP) delivered in solution or coated onto titanium-hydroxyapatite (TiHA) surfaces. Herein, we focus on the comparison of in vitro osteogenic efficacy in mouse C2C12 pre-osteoblasts of three BMP members, namely: BMP-2, BMP-6 and BMP-7. In parallel, we evaluated the molecular binding strength between each BMP with FN using the Surface Plasmon Resonance (SPR) technology. The affinity of BMPs for FN was found totally different and dependent on BMP type. Indeed, the combination of FN with BMP-2 on TiHA surfaces potentiates the burst of gene-mediated osteogenic induction, while it prolongs the osteogenic activity of BMP-6 and surprisingly annihilates the BMP-7 one. These results correlate with FN/BMP affinity for TiHA, since BMP-6>BMP-2>BMP-7. In addition, by analyzing the osteogenic activity in the peri-implant environment, we showed that osteoinductive paracrine effects were significantly decreased upon (FN/BMP-6), as opposed to (FN/BMP-2) coatings. Altogether, our results support the use of FN/BMP-6 to develop a biomimetic microenvironment capable to induce osteogenic activity under physiological conditions, with minimum paracrine signalization. STATEMENT OF SIGNIFICANCE: The originality of our paper relies on the first direct comparison of the in vitro osteogenic potential of three osteogenic BMPs (BMP-2, -6 and -7) combined with native human plasma fibronectin delivered in solution or coated by laser transfer onto titanium hydroxyapatite surfaces. We confirm that BMP association with fibronectin enhances the osteogenic activity of BMP-2, -6 and -7, but with essential discrepancies, depending on the BMP member, and in agreement with the affinity of BMPs for fibronectin. Moreover, we bring elements to explain the origin of the BMP-2 medical life-threatening side-effects by analyzing in vitro paracrine effects. Finally, this work supports the alternative use of FN/BMP-6 to induce osteogenic activity under physiological conditions, with minimum side effects.


Assuntos
Materiais Biomiméticos , Proteína Morfogenética Óssea 2 , Proteína Morfogenética Óssea 6 , Proteína Morfogenética Óssea 7 , Materiais Revestidos Biocompatíveis , Durapatita , Fibronectinas , Osteoblastos/metabolismo , Titânio , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/farmacologia , Proteína Morfogenética Óssea 6/química , Proteína Morfogenética Óssea 6/farmacologia , Proteína Morfogenética Óssea 7/química , Proteína Morfogenética Óssea 7/farmacologia , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/química , Durapatita/farmacologia , Fibronectinas/química , Fibronectinas/farmacologia , Humanos , Camundongos , Osteoblastos/citologia , Titânio/química , Titânio/farmacologia
9.
Biol Open ; 4(3): 345-54, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25681395

RESUMO

Although the regulation of epithelial morphogenesis is essential for the formation of tissues and organs in multicellular organisms, little is known about how signalling pathways control cell shape changes in space and time. In the Drosophila ovarian epithelium, the transition from a cuboidal to a squamous shape is accompanied by a wave of cell flattening and by the ordered remodelling of E-cadherin-based adherens junctions. We show that activation of the TGFß pathway is crucial to determine the timing, the degree and the dynamic of cell flattening. Within these cells, TGFß signalling controls cell-autonomously the formation of Actin filament and the localisation of activated Myosin II, indicating that internal forces are generated and used to remodel AJ and to promote cytoskeleton rearrangement. Our results also reveal that TGFß signalling controls Notch activity and that its functions are partly executed through Notch. Thus, we demonstrate that the cells that undergo the cuboidal-to-squamous transition produce active cell-shaping mechanisms, rather than passively flattening in response to a global force generated by the growth of the underlying cells. Thus, our work on TGFß signalling provides new insights into the mechanisms through which signal transduction cascades orchestrate cell shape changes to generate proper organ structure.

10.
FEBS J ; 276(22): 6537-47, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19804411

RESUMO

Olfaction is primarily mediated by the large family of olfactory receptors. Although all insect olfactory receptors share the same structure with seven transmembrane domains, they present poor sequence homologies within and between species. As the only exception, Drosophila melanogaster OR83b and its orthologues define a receptor subtype singularly conserved between insect species. In this article, we report the identification of a new subtype of putative olfactory receptors exceptionally conserved within noctuids, a taxonomic group that includes crop pest insects. Through homology-based molecular cloning, homologues of the previously identified OR18 from Heliothis virescens were identified in the antennae of six noctuid species from various genera, presenting an average of 88% sequence identity. No orthologues were found in genomes available from diverse insect orders and selection pressure analysis revealed that the noctuid OR18s are under purifying selection. The OR18 gene was studied in details in the cotton leafworm, Spodoptera littoralis, where it presented all the characteristic features of an olfactory receptor encoding gene: its expression was restricted to the antennae, with expression in both sexes; its developmental expression pattern was reminiscent of that from other olfactory genes; and in situ hybridization experiments within the antennae revealed that the receptor-expressing cells were closely associated with the olfactory structures, including pheromone- and non-pheromone-sensitive structures. Taken together, our data suggest that we have identified a new original subtype of olfactory receptors that are extremely conserved within noctuids and that might fulfil a critical function in male and female noctuid chemosensory neurones.


Assuntos
Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Lepidópteros/genética , Lepidópteros/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Insetos/química , Proteínas de Insetos/classificação , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Receptores Odorantes/química , Receptores Odorantes/classificação , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
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