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1.
Plant Mol Biol ; 114(1): 8, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291213

RESUMO

In bread wheat (Triticum aestivum L.), chromosome associations during meiosis are extremely regulated and initiate at the telomeres and subtelomeres, which are enriched in satellite DNA (satDNA). We present the study and characterization of the bread wheat satellitome to shed light on the molecular organization of wheat subtelomeres. Our results revealed that the 2.53% of bread wheat genome is composed by satDNA and subtelomeres are particularly enriched in such DNA sequences. Thirty-four satellite DNA (21 for the first time in this work) have been identified, analyzed and cytogenetically validated. Many of the satDNAs were specifically found at particular subtelomeric chromosome regions revealing the asymmetry in subtelomere organisation among the wheat subgenomes, which might play a role in proper homologous recognition and pairing during meiosis. An integrated physical map of the wheat satellitome was also constructed. To the best of our knowledge, our results show that the combination of both cytogenetics and genome research allowed the first comprehensive analysis of the wheat satellitome, shedding light on the complex wheat genome organization, especially on the polymorphic nature of subtelomeres and their putative implication in chromosome recognition and pairing during meiosis.


Assuntos
Genoma de Planta , Triticum , Triticum/genética , DNA Satélite , Pão , Sequência de Bases
2.
Plants (Basel) ; 12(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37687390

RESUMO

Rice (Oryza sativa L.) is a very important cereal worldwide, since it is the staple food for more than half of the world's population. Iron (Fe) deficiency is among the most important agronomical concerns in calcareous soils where rice plants may suffer from this deficiency. Current production systems are based on the use of high-yielding varieties and the application of large quantities of agrochemicals, which can cause major environmental problems. The use of beneficial rhizosphere microorganisms is considered a relevant sustainable alternative to synthetic fertilizers. The main goal of this study was to determine the ability of the nonpathogenic strain Fusarium oxysporum FO12 to induce Fe-deficiency responses in rice plants and its effects on plant growth and Fe chlorosis. Experiments were carried out under hydroponic system conditions. Our results show that the root inoculation of rice plants with FO12 promotes the production of phytosiderophores and plant growth while reducing Fe chlorosis symptoms after several days of cultivation. Moreover, Fe-related genes are upregulated by FO12 at certain times in inoculated plants regardless of Fe conditions. This microorganism also colonizes root cortical tissues. In conclusion, FO12 enhances Fe-deficiency responses in rice plants, achieves growth promotion, and reduces Fe chlorosis symptoms.

3.
Crit Rev Toxicol ; 53(7): 385-411, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37646804

RESUMO

Chemical regulatory authorities around the world require systemic toxicity data from acute exposures via the oral, dermal, and inhalation routes for human health risk assessment. To identify opportunities for regulatory uses of non-animal replacements for these tests, we reviewed acute systemic toxicity testing requirements for jurisdictions that participate in the International Cooperation on Alternative Test Methods (ICATM): Brazil, Canada, China, the European Union, Japan, South Korea, Taiwan, and the USA. The chemical sectors included in our review of each jurisdiction were cosmetics, consumer products, industrial chemicals, pharmaceuticals, medical devices, and pesticides. We found acute systemic toxicity data were most often required for hazard assessment, classification, and labeling, and to a lesser extent quantitative risk assessment. Where animal methods were required, animal reduction methods were typically recommended. For many jurisdictions and chemical sectors, non-animal alternatives are not accepted, but several jurisdictions provide guidance to support the use of test waivers to reduce animal use for specific applications. An understanding of international regulatory requirements for acute systemic toxicity testing will inform ICATM's strategy for the development, acceptance, and implementation of non-animal alternatives to assess the health hazards and risks associated with acute toxicity.

4.
Nanoscale ; 15(29): 12280-12286, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37401747

RESUMO

Carbon nanohorns have been non-covalently functionalized with two different benzothiadiazoloquinoxalines prepared via Stille cross-coupling reactions under solvent-free conditions and microwave irradiation. The close interactions between these organic molecules and the nanostructures resulted in a prominent Raman enhancement, which makes them attractive candidates for multiple applications. A complete experimental physico-chemical characterization has been combined with in silico studies to understand these phenomena. The processability of the hybrids was exploited to prepare homogeneous films on substrates with different natures.

5.
J Clin Med ; 12(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37297811

RESUMO

Recently, there have been reports of what could be a new lymphoproliferative entity: breast implant-associated Epstein-Barr virus positive (EBV+) diffuse large B-cell lymphoma (EBV+ BIA-DLBCL). The new World Health Organization classification has categorized it as fibrin-associated large B-cell lymphomas (FA-LBCLs); therefore, it could be referred to as breast implant-associated fibrin-associated large B-cell lymphomas (BIA-FA-LBCLs). Although the association between breast implants and lymphomas has been known since the mid-1990s, it has been almost exclusively breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). Here, we describe the first case of BIA-FA-LBCL at our center, with a literature review of the clinical features, diagnosis and treatment approach of this lymphoma. We also explore the differential diagnosis of BIA-FA-LBCL, highlighting the diagnostic challenges and the reasons that have led these lymphomas to being labeled as a new face of FA-LBCL.

6.
Chemistry ; 29(46): e202301639, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37265227

RESUMO

A series of donor-π-acceptor-π-donor (D-π-A-π-D) compounds based on naphthalendiimide (NDI) and perylenediimide (PDI) central cores combined with triphenylamine and phenylcarbazole donor groups have been synthesized, characterized and tested in top-contact/bottom gate organic field-effect transistors (OFETs). The results showed high electron mobilities, up to 0.3 cm2 V-1 s-1 , in the case of NDI derivatives and moderate values of around 10-3  cm2 V-1 s-1 for PDI-based semiconductors. Quantum chemical calculations were performed in order to support the experimental data. The results suggest that adequate molecular characteristics and larger crystalline domains in NDI vs. PDI semiconducting films may be the reasons behind the enhanced electrical properties of NDI derivatives. Furthermore, when the lateral donor substituents are triphenylamine groups, the mobilities were slightly higher in comparison to phenylcarbazole donor groups due to an improved electron-donating character. Other characterization techniques, such as AFM, X-ray diffraction or spectroelectrochemistry, among others, have been performed to analyze supramolecular order, charge carriers' nature and stability, parameters closely related to charge transport characteristics.

7.
Molecules ; 28(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37375189

RESUMO

A new series of donor-acceptor-donor (D-A-D) structures derived from arylethynyl 1H-benzo[d]imidazole was synthesized and processed into single crystals with the goal of testing such crystals' ability to act as optical waveguides. Some crystals displayed luminescence in the 550-600 nm range and optical waveguiding behavior with optical loss coefficients around 10-2 dB/µm, which indicated a notable light transport. The crystalline structure, confirmed by X-ray diffraction, contains internal channels that are important for light propagation, as we previously reported. The combination of a 1D assembly, a single crystal structure, and notable light emission properties with low losses from self-absorption made 1H-benzo[d]imidazole derivatives appealing compounds for optical waveguide applications.

8.
Dis Markers ; 2023: 7589017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37101837

RESUMO

Background: Sinusoidal obstructive syndrome (SOS) is a potentially fatal complication secondary to hematopoietic stem cell transplant (HSCT) conditioning. Endothelial damage plasma biomarkers such as plasminogen activator inhibitor-1 (PAI-1), hyaluronic acid (HA), and vascular adhesion molecule-1 (VCAM1) represent potential diagnostic tools for SOS. Methods: We prospectively collected serial citrated blood samples (baseline, day 0, day 7, and day 14) in all adult patients undergoing HSCT at La Paz Hospital, Madrid. Samples were later analyzed by ELISA (enzyme-linked immunosorbent assay) for HA, VCAM1, and PAI-1 concentrations. Results: During sixteen months, we prospectively recruited 47 patients. Seven patients (14%) were diagnosed with SOS according to the EBMT criteria for SOS/VOD diagnosis and received treatment with defibrotide. Our study showed a statistically significant elevation of HA on day 7 in SOS patients, preceding clinical SOS diagnosis, with a sensitivity of 100%. Furthermore, we observed a significant increase of HA and VCAM1 levels on day 14. Regarding risk factors, we observed a statistically significant association between SOS diagnosis and the fact that patients received 3 or more previous lines of treatment before HSCT. Conclusions: The early significant increase in HA levels observed opens the door to a noninvasive peripheral blood test which could have the potential to improve diagnosis and facilitate prophylactic and therapeutic management of SOS before clinical/histological damage is established.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Hepatopatia Veno-Oclusiva , Adulto , Humanos , Hepatopatia Veno-Oclusiva/diagnóstico , Hepatopatia Veno-Oclusiva/etiologia , Hepatopatia Veno-Oclusiva/tratamento farmacológico , Ácido Hialurônico , Inibidor 1 de Ativador de Plasminogênio , Polidesoxirribonucleotídeos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Molécula 1 de Adesão de Célula Vascular
9.
J Speech Lang Hear Res ; 66(3): 951-965, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36763840

RESUMO

PURPOSE: Though the frequency of gesture use by infants has been related to the development of different language abilities in the initial stages of language acquisition, less is known about whether this frequency (or "gesture rate") continues to correlate with language measures in later stages of language acquisition, or whether the relation to language skills also depends on the accuracy with which such gestures are produced (or reproduced). This study sets out to explore whether preschoolers' narrative abilities are related to these two variables, namely, gesture rate and gesture accuracy. METHOD: A total of 31 typically developing 3- to 4-year-old children participated in a multimodal imitation task, a context-based gesture elicitation task, and a narrative retelling task. RESULTS: Results showed that there was a significant positive correlation between the children's narrative scores and their gesture accuracy scores, whereas higher rates of gesture use did not correlate with higher levels of narrative skill. Further multimodal regression analysis confirmed that gesture accuracy was a positive predictor of narrative performance, and moreover, showed that gesture rate was a negative predictor. CONCLUSIONS: The fact that both gesture accuracy and gesture rate are strongly and differently linked to oral language abilities supports the claim that language and gesture are highly complex systems, and that complementary measures of gesture performance can help us assess with greater granularity the relationship between gesture and language development. These findings highlight the need to use gesture during clinical assessments as an informative indicator of language development and suggest that future research should further investigate the value of multimodal programs in the treatment of language and communication disorders.


Assuntos
Transtornos da Comunicação , Gestos , Lactente , Humanos , Pré-Escolar , Desenvolvimento da Linguagem , Idioma , Aptidão
10.
Planta ; 257(3): 50, 2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36757472

RESUMO

MAIN CONCLUSION: FO12 strain enhances Fe deficiency responses in cucumber plants, probably through the production of ethylene and NO in the subapical regions of the roots. Rhizosphere microorganisms can elicit induced systemic resistance (ISR) in plants. This type of resistance involves complex mechanisms that confer protection to the plant against pathogen attack. Additionally, it has been reported by several studies that ISR and Fe deficiency responses are modulated by common pathways, involving some phytohormones and signaling molecules, like ethylene and nitric oxide (NO). The aim of this study was to determine whether the nonpathogenic strain of Fusarium oxysporum FO12 can induce Fe deficiency responses in cucumber (Cucumis sativus L.) plants. Our results demonstrate that the root inoculation of cucumber plants with the FO12 strain promotes plant growth after several days of cultivation, as well as rhizosphere acidification and enhancement of ferric reductase activity. Moreover, Fe-related genes, such as FRO1, IRT1 and HA1, are upregulated at certain times after FO12 inoculation either upon Fe-deficiency or Fe-sufficient conditions. Furthermore, it has been found that this fungus colonizes root cortical tissues, promoting the upregulation of ethylene synthesis genes and NO production in the root subapical regions. To better understand the effects of the FO12 strain on field conditions, cucumber plants were inoculated and cultivated in a calcareous soil under greenhouse conditions. The results obtained show a modification of some physiological parameters in the inoculated plants, such as flowering and reduction of tissue necrosis. Overall, the results suggest that the FO12 strain could have a great potential as a Fe biofertilizer and biostimulant.


Assuntos
Cucumis sativus , Fusarium , Cucumis sativus/genética , Raízes de Plantas/metabolismo , Ferro/metabolismo , Etilenos/metabolismo
11.
J Speech Lang Hear Res ; 66(3): 888-900, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36809062

RESUMO

PURPOSE: This study aims to analyze the development of gesture-speech temporal alignment patterns in children's narrative speech from a longitudinal perspective and, specifically, the potential differences between different gesture types, namely, gestures that imagistically portray or refer to semantic content in speech (i.e., referential gestures) and those that lack semantic content (i.e., non-referential gestures). METHOD: This study uses an audiovisual corpus of narrative productions (n = 332) from 83 children (43 girls, 40 boys) who participated in a narrative retelling task at two time points in development (at 5-6 and 7-9 years of age). The 332 narratives were coded for both manual co-speech gesture types and prosody. Gestural annotations included gesture phasing (i.e., preparation, stroke, hold, and recovery) and gesture types (in terms of referentiality, i.e., referential and non-referential), whereas prosodic annotations included pitch-accented syllables. RESULTS: Results revealed that by ages 5-6 years, children already temporally aligned the stroke of both referential and non-referential gestures with pitch-accented syllables, showing no significant differences between these two gesture types. CONCLUSIONS: The results of the present study contribute to the view that both referential and non-referential gestures are aligned with pitch accentuation, and therefore, this is not only a characteristic of non-referential gestures. Our results also add support to McNeill's phonological synchronization rule from a developmental perspective and indirectly back up recent theories about the biomechanics of gesture-speech alignment, suggesting that this is an inherent ability of oral communication.


Assuntos
Gestos , Fala , Masculino , Feminino , Humanos , Criança , Pré-Escolar , Linguística , Semântica , Narração
12.
J Child Lang ; 50(1): 52-77, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36503549

RESUMO

Over recent decades much research has analyzed the relevance of 9- to 20- month-old infants' early imitation skills (object- and language-based imitation) for language development. Yet there have been few systematic comparisons of the joint relevance of these imitative behaviors later on in development. This correlational study investigated whether multimodal imitation (gestural, prosodic, and lexical components) and object-based imitation are related to narratives and sociopragmatics in preschoolers. Thirty-one typically developing 3- to 4-year-old children performed four tasks to assess multimodal imitation, object-based imitation, narrative abilities, and sociopragmatic abilities. Results revealed that both narrative and sociopragmatic skills were significantly related to multimodal imitation, but not to object-based imitation, indicating that preschoolers' ability to imitate socially relevant multimodal cues is strongly related to language and sociocommunicative skills. Therefore, this evidence supports a broader conceptualization of imitation behaviors in the field of language development that systematically integrates prosodic, gestural, and verbal linguistic patterns.


Assuntos
Comportamento Imitativo , Desenvolvimento da Linguagem , Pré-Escolar , Lactente , Humanos , Gestos , Idioma , Sinais (Psicologia)
15.
Micromachines (Basel) ; 13(12)2022 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-36557552

RESUMO

A method based on the photographic recording of the power distribution laterally diffused by cationic-network (CN) hydrogel waveguides is first checked against the well-established cut-back method and then used to determine the different contributions to optical power attenuation along the hydrogel-based waveguide. Absorption and scattering loss coefficients are determined for 450 nm, 532 nm and 633 nm excitation. The excellent optical loss values obtained (0.32-1.95 dB/cm), similar to others previously described, indicate their potential application as waveguides in different fields, including soft robotic and light-based therapies.

16.
EJHaem ; 3(3): 722-733, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36051055

RESUMO

Diffuse large B-cell lymphoma (DLBCL), the most frequent non-Hodgkin's lymphoma subtype, is characterized by strong biological, morphological, and clinical heterogeneity, but patients are treated with immunochemotherapy in a relatively homogeneous way. Here, we have used a customized NanoString platform to analyze a series of 197 homogeneously treated DLBCL cases. The platform includes the most relevant genes or signatures known to be useful for predicting response to R-CHOP (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone) in DLBCL cases. We generated a risk score that combines the International Prognostic Index with cell of origin and double expression of MYC/BCL2, and stratified the series into three groups, yielding hazard ratios from 0.15 to 5.49 for overall survival, and from 0.17 to 5.04 for progression-free survival. Group differences were highly significant (p < 0.0001), and the scoring system was applicable to younger patients (<60 years of age) and patients with advanced or localized stages of the disease. Results were validated in an independent dataset from 166 DLBCL patients treated in two distinct clinical trials. This risk score combines clinical and biological data in a model that can be used to integrate biological variables into the prognostic models for DLBCL cases.

17.
Regul Toxicol Pharmacol ; 135: 105261, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36103951

RESUMO

New Approach Methodologies (NAMs) are considered to include any in vitro, in silico or chemistry-based method, as well as the strategies to implement them, that may provide information that could inform chemical safety assessment. Current chemical legislation in the European Union is limited in its acceptance of the widespread use of NAMs. The European Partnership for Alternative Approaches to Animal Testing (EPAA) therefore convened a 'Deep Dive Workshop' to explore the use of NAMs in chemical safety assessment, the aim of which was to support regulatory decisions, whilst intending to protect human health. The workshop recognised that NAMs are currently used in many industrial sectors, with some considered as fit for regulatory purpose. Moreover, the workshop identified key discussion points that can be addressed to increase the use and regulatory acceptance of NAMs. These are based on the changes needed in frameworks for regulatory requirements and the essential needs in education, training and greater stakeholder engagement as well the gaps in the scientific basis of NAMs.


Assuntos
Alternativas aos Testes com Animais , Testes de Toxicidade , Animais , União Europeia , Humanos , Indústrias , Medição de Risco , Testes de Toxicidade/métodos
18.
Molecules ; 27(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35889212

RESUMO

In this work, as an equivocal proof of the potential of microwave irradiation in organic synthesis, a complex pyrazine-decorated benzotriazole derivative that is challenging to prepare under conventional conditions has been obtained upon microwave irradiation, thus efficiently improving the process and yields, dramatically decreasing the reaction times and resulting in an environmentally friendly synthetic procedure. In addition, this useful derivative could be applied in organic electronics, specifically in organic field-effect transistors (OFETs), exhibiting the highest electron mobilities reported to date for benzotriazole discrete molecules, of around 10-2 cm2V-1s-1.


Assuntos
Micro-Ondas , Semicondutores , Elétrons , Transistores Eletrônicos , Triazóis
19.
Sci Rep ; 12(1): 10597, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732879

RESUMO

The increasing human population demands an increase in crop yields that must be implemented through breeding programmes to ensure a more efficient and sustainable production of agro-food products. In the framework of breeding, genetic crosses are developed between cultivated species such as wheat and their relative species that are used as genetic donors to transfer desirable agronomic traits into the crop. Unfortunately, interspecific associations between chromosomes from the donor species and the cultivar are rare during meiosis, the process to produce gametes in organisms with sexual reproduction, hampering the transfer of genetic variability into wheat. In addition, little is known about how homologous (equivalent) chromosomes initiate interaction and recognition within the cell nucleus to enter meiosis. In this context, we aim to get insight into wheat chromatin structure, particularly the distribution of homologous chromosomes within the cell nucleus and their putative interactions in premeiotic stages to facilitate chromosome associations and recombination at the beginning of meiosis. Cytogenetics allows the study of both the structure and the behaviour of chromosomes during meiosis and is key in plant breeding. In this study we visualized an extra pair of barley homologous chromosomes in a wheat genetic background to study the spatial distribution, arrangements and interactions occurring exclusively between this pair of homologous chromosomes during premeiosis using fluorescence in situ hybridization (FISH). Our results suggest that homologous chromosomes can initiate interactions in premeiotic stages that could facilitate the processes of specific chromosome recognition and association occurring at the onset of meiosis.


Assuntos
Melhoramento Vegetal , Triticum , Pareamento Cromossômico/genética , Cromossomos , Hibridização in Situ Fluorescente , Meiose/genética , Triticum/genética
20.
Nat Commun ; 13(1): 1786, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379806

RESUMO

Hydroxycinnamic acids present in plant cuticles, the interphase and the main protective barrier between the plant and the environment, exhibit singular photochemical properties that could allow them to act as a UV shield. Here, we employ transient absorption spectroscopy on isolated cuticles and leaf epidermises to study in situ the photodynamics of these molecules in the excited state. Based on quantum chemical calculations on p-coumaric acid, the main phenolic acid present in the cuticle, we propose a model in which cuticle phenolics display a photoprotective mechanism based in an ultrafast and non-radiative excited state deactivation combined with fluorescence emission. As such, the cuticle can be regarded as the first and foremost protective barrier against UV radiation. This photostable and photodynamic mechanism seems to be universal in land plants giving a special role and function to the presence of different aromatic domains in plant cuticles and epidermises.


Assuntos
Plantas , Raios Ultravioleta , Fluorescência , Fenóis , Folhas de Planta/fisiologia
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