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1.
Sensors (Basel) ; 23(3)2023 Jan 23.
Article de Anglais | MEDLINE | ID: mdl-36772338

RÉSUMÉ

Nowadays, the study of the gait by analyzing the distribution of plantar pressure is a well-established technique. The use of intelligent insoles allows real-time monitoring of the user. Thus, collecting and analyzing information is a more accurate process than consultations in so-called gait laboratories. Most of the previous published studies consider the composition and operation of these insoles based on resistive sensors. However, the use of capacitive sensors could provide better results, in terms of linear behavior under the pressure exerted. This behavior depends on the properties of the dielectric used. In this work, the design and implementation of an intelligent plantar insole composed of capacitive sensors is proposed. The dielectric used is a polydimethylsiloxane (PDMS)-based composition. The sensorized plantar insole developed achieves its purpose as a tool for collecting pressure in different areas of the sole of the foot. The fundamentals and details of the composition, manufacture, and implementation of the insole and the system used to collect data, as well as the data samples, are shown. Finally, a comparison of the behavior of both insoles, resistive and capacitive sensor-equipped, is made. The prototype presented lays the foundation for the development of a tool to support the diagnosis of gait abnormalities.


Sujet(s)
Démarche , Chaussures , Pression , Pied , Polydiméthylsiloxanes , Marche à pied
2.
BMC Genomics ; 23(1): 144, 2022 Feb 17.
Article de Anglais | MEDLINE | ID: mdl-35176993

RÉSUMÉ

BACKGROUND: DNA methylation is thought to influence the expression of genes, especially in response to changing environmental conditions and developmental changes. Sugar beet (Beta vulgaris ssp. vulgaris), and other biennial or perennial plants are inevitably exposed to fluctuating temperatures throughout their lifecycle and might even require such stimulus to acquire floral competence. Therefore, plants such as beets, need to fine-tune their epigenetic makeup to ensure phenotypic plasticity towards changing environmental conditions while at the same time steering essential developmental processes. Different crop species may show opposing reactions towards the same abiotic stress, or, vice versa, identical species may respond differently depending on the specific kind of stress. RESULTS: In this study, we investigated common effects of cold treatment on genome-wide DNA methylation and gene expression of two Beta vulgaris accessions via multi-omics data analysis. Cold exposure resulted in a pronounced reduction of DNA methylation levels, which particularly affected methylation in CHH context (and to a lesser extent CHG) and was accompanied by transcriptional downregulation of the chromomethyltransferase CMT2 and strong upregulation of several genes mediating active DNA demethylation. CONCLUSION: Integration of methylomic and transcriptomic data revealed that, rather than methylation having directly influenced expression, epigenetic modifications correlated with changes in expression of known players involved in DNA (de)methylation. In particular, cold triggered upregulation of genes putatively contributing to DNA demethylation via the ROS1 pathway. Our observations suggest that these transcriptional responses precede the cold-induced global DNA-hypomethylation in non-CpG, preparing beets for additional transcriptional alterations necessary for adapting to upcoming environmental changes.


Sujet(s)
Beta vulgaris , Beta vulgaris/génétique , Méthylation de l'ADN , Épigenèse génétique , Expression des gènes , Protein-tyrosine kinases/génétique , Protein-tyrosine kinases/métabolisme , Protéines proto-oncogènes/génétique , Sucres/métabolisme
3.
J Exp Bot ; 72(10): 3688-3703, 2021 05 04.
Article de Anglais | MEDLINE | ID: mdl-33712830

RÉSUMÉ

Cassava storage roots are among the most important root crops worldwide, and represent one of the most consumed staple foods in sub-Saharan Africa. The vegetatively propagated tropical shrub can form many starchy tuberous roots from its stem. These storage roots are formed through the activation of secondary root growth processes. However, the underlying genetic regulation of storage root development is largely unknown. Here we report distinct structural and transcriptional changes occurring during the early phases of storage root development. A pronounced increase in auxin-related transcripts and the transcriptional activation of secondary growth factors, as well as a decrease in gibberellin-related transcripts were observed during the early stages of secondary root growth. This was accompanied by increased cell wall biosynthesis, most notably increased during the initial xylem expansion within the root vasculature. Starch storage metabolism was activated only after the formation of the vascular cambium. The formation of non-lignified xylem parenchyma cells and the activation of starch storage metabolism coincided with increased expression of the KNOX/BEL genes KNAT1, PENNYWISE, and POUND-FOOLISH, indicating their importance for proper xylem parenchyma function.


Sujet(s)
Cambium , Manihot , Cambium/génétique , Cambium/métabolisme , Régulation de l'expression des gènes végétaux , Acides indolacétiques , Manihot/génétique , Manihot/métabolisme , Protéines végétales/génétique , Protéines végétales/métabolisme , Racines de plante/métabolisme
4.
Front Oncol ; 10: 596493, 2020.
Article de Anglais | MEDLINE | ID: mdl-33344244

RÉSUMÉ

BACKGROUND: Human malignant melanoma is a highly aggressive, heterogeneous and drug-resistant cancer. Due to a high number of clones, harboring various mutations that affect key pathways, there is an exceptional level of phenotypic variation and intratumor heterogeneity (ITH) in melanoma. This poses a significant challenge to personalized cancer medicine. Hitherto, it remains unclear to what extent the heterogeneity of melanoma affects the immune microenvironment. Herein, we explore the interaction between the tumor heterogeneity and the host immune response in a melanoma cohort utilizing The Cancer Genome Atlas (TCGA). METHODS: Clonal Heterogeneity Analysis Tool (CHAT) was used to estimate intratumor heterogeneity, and immune cell composition was estimated using CIBERSORT. The Overall Survival (OS) among groups was analyzed using Kaplan-Meier curves with the log-rank test and multivariate cox regression. RNA-seq data were evaluated to identify differentially expressed immunomodulatory genes. The reverse phase protein array (RPPA) data platform was used to validate immune responses at protein level. RESULTS: Tumors with high heterogeneity were associated with decreased overall survival (p = 0.027). High CHAT tumors were correlated with less infiltration by anti-tumor CD8 T cells (p = 0.0049), T follicular cells (p = 0.00091), and M1 macrophages (p = 0.0028), whereas tumor-promoting M2 macrophages were increased (p = 0.02). High CHAT tumors correlated with a reduced expression of immunomodulatory genes, particularly Programmed Cell Death 1 (PD1) and its ligand PD-L1. In addition, high CHAT tumors exhibited lower immune Cytotoxic T lymphocytes (CTLs)-mediated toxicity pathway score (p = 2.9E-07) and cytotoxic pathway score (p = 2.9E-08). High CHAT tumors were also associated with a lower protein level of immune-regulatory kinases, such as lymphocyte-specific protein tyrosine kinase (LCK) (p = 3.4e-5) and spleen tyrosine kinase (SYK) (p = 0.0011). CONCLUSIONS: Highly heterogeneous melanoma tumors are associated with reduced immune cell infiltration and immune response activation as well as decreased survival. Our results reveal that intratumor heterogeneity is an indicative factor for patient survival due to its impact on anti-tumor immune response.

5.
Plant Cell ; 32(10): 3206-3223, 2020 10.
Article de Anglais | MEDLINE | ID: mdl-32769131

RÉSUMÉ

During their first year of growth, overwintering biennial plants transport Suc through the phloem from photosynthetic source tissues to storage tissues. In their second year, they mobilize carbon from these storage tissues to fuel new growth and reproduction. However, both the mechanisms driving this shift and the link to reproductive growth remain unclear. During vegetative growth, biennial sugar beet (Beta vulgaris) maintains a steep Suc concentration gradient between the shoot (source) and the taproot (sink). To shift from vegetative to generative growth, they require a chilling phase known as vernalization. We studied sugar beet sink-source dynamics upon vernalization and showed that before flowering, the taproot underwent a reversal from a sink to a source of carbohydrates. This transition was induced by transcriptomic and functional reprogramming of sugar beet tissue, resulting in a reversal of flux direction in the phloem. In this transition, the vacuolar Suc importers and exporters TONOPLAST SUGAR TRANSPORTER2;1 and SUCROSE TRANSPORTER4 were oppositely regulated, leading to the mobilization of sugars from taproot storage vacuoles. Concomitant changes in the expression of floral regulator genes suggest that these processes are a prerequisite for bolting. Our data will help both to dissect the metabolic and developmental triggers for bolting and to identify potential targets for genome editing and breeding.


Sujet(s)
Beta vulgaris/physiologie , Phloème/métabolisme , Protéines végétales/métabolisme , Pousses de plante/métabolisme , Métabolisme glucidique , Dioxyde de carbone/métabolisme , Basse température , Esculoside/métabolisme , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes végétaux , Phloème/génétique , Photosynthèse/physiologie , Protéines végétales/génétique , Racines de plante/génétique , Racines de plante/métabolisme , Pousses de plante/génétique , Saccharose/métabolisme , Sucres/métabolisme , Vacuoles/génétique , Vacuoles/métabolisme
6.
Sensors (Basel) ; 19(24)2019 Dec 11.
Article de Anglais | MEDLINE | ID: mdl-31835869

RÉSUMÉ

The Internet of Things enables experts of given domains to create smart user experiences for interacting with the environment. However, development of such experiences requires strong programming skills, which are challenging to develop for non-technical users. This paper presents several extensions to the block-based programming language used in App Inventor to make the creation of mobile apps for smart learning experiences less challenging. Such apps are used to process and graphically represent data streams from sensors by applying map-reduce operations. A workshop with students without previous experience with Internet of Things (IoT) and mobile app programming was conducted to evaluate the propositions. As a result, students were able to create small IoT apps that ingest, process and visually represent data in a simpler form as using App Inventor's standard features. Besides, an experimental study was carried out in a mobile app development course with academics of diverse disciplines. Results showed it was faster and easier for novice programmers to develop the proposed app using new stream processing blocks.

7.
Chromosoma ; 128(1): 53-67, 2019 03.
Article de Anglais | MEDLINE | ID: mdl-30617552

RÉSUMÉ

Parasitism evokes adaptive physiological changes in the host, many of which take place through gene expression changes. This response can be more or less local, depending on the organ or tissue affected by the parasite, or else systemic when the parasite affects the entire host body. The most extreme of the latter cases is intragenomic parasitism, where the parasite is present in all host nuclei as any other genomic element. Here, we show the molecular crosstalk between a parasitic chromosome (also named B chromosome) and the host genome, manifested through gene expression changes. The transcriptome analysis of 0B and 1B females of the grasshopper Eyprepocnemis plorans, validated by a microarray experiment performed on four B-lacking and five B-carrying females, revealed changes in gene expression for 188 unigenes being consistent in both experiments. Once discarded B-derived transcripts, there were 46 differentially expressed genes (30 up- and 16 downregulated) related with the adaptation of the host genome to the presence of the parasitic chromosome. Interestingly, the functions of these genes could explain some of the most important effects of B chromosomes, such as nucleotypic effects derived from the additional DNA they represent, chemical defense and detoxification, protein modification and response to stress, ovary function, and regulation of gene expression. Collectively, these changes uncover an intimate host-parasite interaction between A and B chromosomes during crucial steps of gene expression and protein function.


Sujet(s)
Chromosomes d'insecte/composition chimique , Génome d'insecte , Sauterelles/génétique , Interactions hôte-parasite/génétique , Phénotype , Transcriptome , Animaux , Femelle , Régulation de l'expression des gènes , Gene Ontology , Génotype , Sauterelles/parasitologie , Séquençage nucléotidique à haut débit , Annotation de séquence moléculaire , Séquençage par oligonucléotides en batterie , Ovaire/métabolisme , Ovaire/parasitologie
8.
Sci Rep ; 7: 45200, 2017 04 03.
Article de Anglais | MEDLINE | ID: mdl-28367986

RÉSUMÉ

For many years, parasitic B chromosomes have been considered genetically inert elements. Here we show the presence of ten protein-coding genes in the B chromosome of the grasshopper Eyprepocnemis plorans. Four of these genes (CIP2A, GTPB6, KIF20A, and MTG1) were complete in the B chromosome whereas the six remaining (CKAP2, CAP-G, HYI, MYCB2, SLIT and TOP2A) were truncated. Five of these genes (CIP2A, CKAP2, CAP-G, KIF20A, and MYCB2) were significantly up-regulated in B-carrying individuals, as expected if they were actively transcribed from the B chromosome. This conclusion is supported by three truncated genes (CKAP2, CAP-G and MYCB2) which showed up-regulation only in the regions being present in the B chromosome. Our results indicate that B chromosomes are not so silenced as was hitherto believed. Interestingly, the five active genes in the B chromosome code for functions related with cell division, which is the main arena where B chromosome destiny is played. This suggests that B chromosome evolutionary success can lie on its gene content.


Sujet(s)
Chromosomes d'insecte/génétique , Sauterelles/génétique , Protéines d'insecte/génétique , Animaux
9.
BMC Res Notes ; 4: 303, 2011 Aug 19.
Article de Anglais | MEDLINE | ID: mdl-21851639

RÉSUMÉ

BACKGROUND: Apomixis, a natural form of asexual seed production in plants, is considered to have great biotechnological potential for agriculture. It has been hypothesised that de-regulation of the sexual developmental pathway could trigger apomictic reproduction. The genus Boechera represents an interesting model system for understanding apomixis, having both sexual and apomictic genotypes at the diploid level. Quantitative qRT-PCR is the most extensively used method for validating genome-wide gene expression analyses, but in order to obtain reliable results, suitable reference genes are necessary. In this work we have evaluated six potential reference genes isolated from a 454 (FLX) derived cDNA library of Boechera. RNA from live microdissected ovules and anthers at different developmental stages, as well as vegetative tissues of apomictic and sexual Boechera, were used to validate the candidates. RESULTS: Based on homologies with Arabidopsis, six genes were selected from a 454 cDNA library of Boechera: RPS18 (Ribosomal sub protein 18), Efalpha1 (Elongation factor 1 alpha), ACT 2 (Actin2), UBQ (polyubiquitin), PEX4 (Peroxisomal ubiquitin conjugating enzyme) and At1g09770.1 (Arabidopsis thaliana cell division cycle 5). Total RNA was extracted from 17 different tissues, qRT-PCRs were performed, and raw Ct values were analyzed for primer efficiencies and gene ratios. The geNorm and normFinder applications were used for selecting the most stable genes among all tissues and specific tissue groups (ovule, anthers and vegetative tissues) in both apomictic and sexual plants separately. Our results show that BoechRPS18, BoechEfα1, BoechACT2 and BoechUBQ were the most stable genes. Based on geNorm, the combinations of BoechRPS18 and BoechEfα1 or BoechUBQ and BoechEfα1 were the most stable in the apomictic plant, while BoechRPS18 and BoechACT2 or BoechUBQ and BoechACT2 performed best in the sexual plant. When subgroups of tissue samples were analyzed, different optimal combinations were identified in sexual ovules (BoechUBQ and BoechEfα1), in anthers from both reproductive systems (BoechACT2 and BoechEfα1), in apomictic vegetative tissues (BoechEfα1 and BoechACT2) and sexual vegetative tissues (BoechRPS18 and BoechEfα1). NormFinder ranked BoechACT2 as the most stable in the apomictic plant, while BoechRPS18 was the best in the sexual plant. The subgroups analysis identified the best gene for both apomictic and sexual ovules (BoechRPS18), for anthers from both reproductive system (BoechEfα1) and for apomictic and vegetative tissues (BoechACT2 and BoechRPS18 respectively) CONCLUSIONS: From a total of six tested genes, BoechRPS18, BoechEfα1, BoechACT2 and BoechUBQ showed the best stability values. We furthermore provide detailed information for the accurate normalization of specific tissue gene expression analyses of apomictic and sexual Boechera.

10.
Plant J ; 58(5): 870-82, 2009 Jun.
Article de Anglais | MEDLINE | ID: mdl-19220792

RÉSUMÉ

Apomixis, a natural form of asexual seed production in plants, has evolved independently in various taxa, and represents an important potential technology for agriculture. The switch to apomixis is based on de-regulation of developmental pathways originally leading to sexual seed formation. Hybridization and polyploidy, both typical characteristics of asexual plants and animals, are mechanisms that could trigger de-regulation. Here we show that up-regulation of alleles in apomeiotic ovules is mediated by genomic duplication, heterochrony and the residual effects of ancient hybridization in diploid apomicts of the Boechera holboellii complex. Using SuperSAGE, we have identified over 4000 differentially expressed mRNA tags between micro-dissected ovules from two diploid sexual (Boechera stricta and B. holboellii) and two diploid apomictic (Boechera divaricarpa) accessions. Pairwise sequence comparisons between tags enabled identification of allelic variants of the same loci. Up-regulated candidate apomeiosis alleles consistently have more than three related alleles, thus demonstrating transcription from duplicated loci. A further 543 alleles were heterochronically expressed between sexual and apomeiotic ovules at developmental stages 2-II to 2-IV. Intriguingly, 69 B. holboellii specific alleles were preferentially up-regulated in apomeiotic ovules, thus showing a remnant'parent of origin' effect stemming from the Pleistocene origin of the hybrid B. divaricarpa from taxa related to B. holboellii and B. stricta. These data implicate polyploid gene dosage in the expression of asexual seed formation, and support hypotheses of de-regulation of the sexual pathway. The observed 'parent of origin' effect suggests that the genomic memory of hybridization has somehow been maintained after hundreds, if not thousands, of asexual generations.


Sujet(s)
Brassicaceae/génétique , Évolution moléculaire , Fleurs/génétique , Reproduction asexuée/génétique , Brassicaceae/physiologie , Biologie informatique , Dosage génique , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes au cours du développement , Régulation de l'expression des gènes végétaux , Banque de gènes , Génome végétal , Méiose , Polyploïdie , ARN des plantes/génétique , Régulation positive
11.
Bioorg Med Chem ; 13(24): 6645-50, 2005 Dec 15.
Article de Anglais | MEDLINE | ID: mdl-16169232

RÉSUMÉ

Several new prenylnaphthohydroquinone derivatives have been prepared through the Diels-Alder condensation between alpha-myrcene and 1,2-benzoquinone and evaluated for their cytotoxic activity against A-549, HT-29 and MB-231 cultured cell lines. All of them have shown GI50 values in the microM level.


Sujet(s)
Antinéoplasiques/composition chimique , Antinéoplasiques/toxicité , Naphtoquinones/composition chimique , Naphtoquinones/toxicité , Prénylamine/analogues et dérivés , Lignée cellulaire tumorale , Survie cellulaire/effets des médicaments et des substances chimiques , Humains , Concentration inhibitrice 50 , Isomérie , Structure moléculaire , Naphtoquinones/synthèse chimique , Prénylamine/synthèse chimique , Prénylamine/composition chimique , Prénylamine/toxicité
12.
J Am Coll Cardiol ; 44(3): 520-7, 2004 Aug 04.
Article de Anglais | MEDLINE | ID: mdl-15358014

RÉSUMÉ

OBJECTIVES: We studied the efficacy of intracoronary brachytherapy (ICB) after successful coronary stenting in diabetic patients with de novo lesions. BACKGROUND: Intracoronary brachytherapy has proven effective in preventing recurrences in patients with in-stent restenosis. However, the role of ICB for the treatment of de novo coronary stenoses remains controversial. METHODS: Ninety-two patients were randomized to either ICB or no radiation after stenting. Primary end points were in-stent mean neointimal area (primary end point of efficacy) and minimal luminal area of the entire vessel segment (primary end point of effectiveness), as assessed by intravascular ultrasound at six-month follow-up. Quantitative coronary angiography analysis was performed at the target, injured, irradiated, and entire vessel segments. RESULTS: At follow-up, the in-stent mean neointimal area was 52% smaller in the ICB group (p < 0.0001). However, there was no difference in the minimal luminal area of the vessel segment (4.5 +/- 2.4 mm2 vs. 4.4 +/- 2.1 mm2). Restenosis rates increased progressively by the analyzed segment in the ICB group: target (7.1% vs. 20.9%, p = 0.07), injured (9.5% vs. 20.9%, p = NS), irradiated (14.3% vs. 20.9%, p = NS), and vessel segment (23.8% vs. 25.6%, p = NS). At one year, 1 cardiac death, 6 myocardial infarctions (MIs) (3 due to late stent thrombosis), and 10 target vessel revascularizations (TVRs) (6 due to the edge effect) occurred in the ICB group, whereas in the nonradiation group, there were 11 TVRs and no deaths or MIs. CONCLUSIONS: Intracoronary brachytherapy significantly inhibited in-stent neointimal hyperplasia after stenting in diabetic patients. However, clinically this was counteracted by the occurrence of the edge effect and late stent thrombosis.


Sujet(s)
Curiethérapie , Sténose coronarienne/imagerie diagnostique , Sténose coronarienne/radiothérapie , Complications du diabète , Endoprothèses , Échographie interventionnelle , Sujet âgé , Resténose coronaire/épidémiologie , Sténose coronarienne/complications , Thrombose coronarienne/étiologie , Mort subite cardiaque/épidémiologie , Femelle , Humains , Hyperplasie/prévention et contrôle , Incidence , Mâle , Adulte d'âge moyen , Infarctus du myocarde/épidémiologie , Réintervention , Endoprothèses/effets indésirables , Résultat thérapeutique , Tunique intime/anatomopathologie
14.
J Med Chem ; 47(5): 1214-22, 2004 Feb 26.
Article de Anglais | MEDLINE | ID: mdl-14971901

RÉSUMÉ

Podophyllotoxin and some of its derivatives are cyclolignans currently used for removing warts and in the clinical treatment of malign neoplasms. As such, they have been an objective of the scientific community for decades, in the search for more potent and more selective anticancer agents. Our interest in the chemoinduction of drug selectivity led us to the design and preparation of new podophyllotoxin derivatives by reaction of podophyllic aldehyde with aliphatic, aromatic, and heteroaromatic amines. Several of the resulting imines displayed a significant selectivity against human colon carcinoma cells, even higher than that of the starting aldehyde. Additional biological studies indicate that these derivatives induce microtubule depolymerization, arrest cells at the G2/M phase of cell cycle, and are able to induce a delayed apoptosis after 48 h of treatment, characterized by caspase-3 activation.


Sujet(s)
Antinéoplasiques/synthèse chimique , Podophyllotoxine/analogues et dérivés , Podophyllotoxine/synthèse chimique , Animaux , Antinéoplasiques/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Cycle cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Tests de criblage d'agents antitumoraux , Humains , Imines/synthèse chimique , Imines/pharmacologie , Souris , Podophyllotoxine/pharmacologie , Relation structure-activité
15.
Buenos Aires; Manuel Marin; 2 ed.; 1948. xvi, 479 p. ^eil..
Monographie de Espagnol | LILACS-Express | BINACIS | ID: biblio-1213356
16.
Buenos Aires; Manuel Marin; 2 ed.; 1948. xvi, 479 p. il.. (109407).
Monographie de Espagnol | BINACIS | ID: bin-109407
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