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1.
Adv Mater ; : e2406671, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38988151

RESUMEN

Supramolecular hydrogels are typically assembled through weak non-covalent interactions, posing a significant challenge in achieving ultra strength. Developing a higher strength based on molecular/nanoscale engineering concepts is a potential improvement strategy. Herein, a super-tough supramolecular hydrogel is assembled by gradually diffusing lignosulfonate sodium (LS) into a polyvinyl alcohol (PVA) solution. Both simulations and analytical results indicate that the assembly and subsequent enhancement of the crosslinked network are primarily attributed to LS-induced formation and gradual densification of strong crystalline domains within the hydrogel. The optimized hydrogel exhibits impressive mechanical properties with tensile strength of ≈20 MPa, Young's modulus of ≈14 MPa, and toughness of ≈50 MJ m⁻3, making it the strongest lignin-PVA/polymer hydrogel known so far. Moreover, LS provides the supramolecular hydrogel with excellent low-temperature stability (<-60 °C), antibacterial, and UV-blocking capability (≈100%). Interestingly, the diffusion ability of LS is demonstrated for self-restructuring damaged supramolecular hydrogel, achieving 3D patterning on hydrogel surfaces, and enhancing the local strength of the freeze-thaw PVA hydrogel. The goal is to foster a versatile hydrogel platform by combining eco-friendly LS with biocompatible PVA, paving the way for innovation and interdisciplinarity in biomedicine, engineering materials, and forestry science.

2.
Plant Physiol ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38918826

RESUMEN

Waterlogging is a serious abiotic stress that drastically decreases crop productivity by damaging the root system. Jasmonic acid (JA) inhibits waterlogging-induced adventitious root (AR) formation in cucumber (Cucumis sativus L.). However, we still lack a profound mechanistic understanding of how JA governs AR formation under waterlogging stress. JAZ (JASMONATE ZIM-DOMAIN) proteins are responsible for repressing JA signaling in a transcriptional manner. In this study, we showed that overexpressing CsJAZ8 inhibited the formation of ARs triggered by waterlogging. Molecular analyses revealed that CsJAZ8 inhibited the activation of the R2R3-MYB transcription factor CsMYB6 via direct interaction. Additionally, silencing of CsMYB6 negatively impacted AR formation under waterlogging stress, as CsMYB6 could directly bind to the promoters of 1-aminocyclopropane-1-carboxylate oxidase2 gene CsACO2 and gibberellin 20-oxidases gene CsGA20ox2, facilitating the transcription of these genes. The overexpression of CsACO2 and CsGA20ox2 led to increased levels of ethylene and gibberellin, which facilitated AR formation under waterlogging conditions. On the contrary, silencing these genes resulted in contrasting phenotypes of AR formation. These results highlight that the transcriptional cascade of CsJAZ8 and CsMYB6 plays a critical role in regulating hormonal-mediated cucumber waterlogging-triggered AR formation by inhibiting ethylene and gibberellin accumulation. We anticipate that our findings will provide insights into the molecular mechanisms that drive the emergence of AR in cucumber plants under waterlogging stress.

3.
Hortic Res ; 11(4): uhae062, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38659441

RESUMEN

Abiotic stressors like waterlogging are detrimental to cucumber development and growth. However, comprehension of the highly complex molecular mechanism underlying waterlogging can provide an opportunity to enhance cucumber tolerance under waterlogging stress. We examined the hypocotyl and stage-specific transcriptomes of the waterlogging-tolerant YZ026A and the waterlogging-sensitive YZ106A, which had different adventitious rooting ability under waterlogging. YZ026A performed better under waterlogging stress by altering its antioxidative machinery and demonstrated a greater superoxide ion (O 2-) scavenging ability. KEGG pathway enrichment analysis showed that a high number of differentially expressed genes (DEGs) were enriched in phenylpropanoid biosynthesis. By pairwise comparison and weighted gene co-expression network analysis analysis, 2616 DEGs were obtained which were categorized into 11 gene co-expression modules. Amongst the 11 modules, black was identified as the common module and yielded a novel key regulatory gene, CsPrx73. Transgenic cucumber plants overexpressing CsPrx73 enhance adventitious root (AR) formation under waterlogging conditions and increase reactive oxygen species (ROS) scavenging. Silencing of CsPrx73 expression by virus-induced gene silencing adversely affects AR formation under the waterlogging condition. Our results also indicated that CsERF7-3, a waterlogging-responsive ERF transcription factor, can directly bind to the ATCTA-box motif in the CsPrx73 promoter to initiate its expression. Overexpression of CsERF7-3 enhanced CsPrx73 expression and AR formation. On the contrary, CsERF7-3-silenced plants decreased CsPrx73 expression and rooting ability. In conclusion , our study demonstrates a novel CsERF7-3-CsPrx73 module that allows cucumbers to adapt more efficiently to waterlogging stress by promoting AR production and ROS scavenging.

4.
Phys Med Biol ; 68(23)2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-37918341

RESUMEN

Objective.Breast architectural distortion (AD), a common imaging symptom of breast cancer, is associated with a particularly high rate of missed clinical detection. In clinical practice, atypical ADs that lack an obvious radiating appearance constitute most cases, and detection models based on single-view images often exhibit poor performance in detecting such ADs. Existing multi-view deep learning methods have overlooked the correspondence between anatomical structures across different views.Approach.To develop a computer-aided detection (CADe) model for AD detection that effectively utilizes the craniocaudal (CC) and mediolateral oblique (MLO) views of digital breast tomosynthesis (DBT) images, we proposed an anatomic-structure-based multi-view information fusion approach by leveraging the related anatomical structure information between these ipsilateral views. To obtain a representation that can effectively capture the similarity between ADs in images from ipsilateral views, our approach utilizes a Siamese network architecture to extract and compare information from both views. Additionally, we employed a triplet module that utilizes the anatomical structural relationship between the ipsilateral views as supervision information.Main results.Our method achieved a mean true positive fraction (MTPF) of 0.05-2.0, false positives (FPs) per volume of 64.40%, and a number of FPs at 80% sensitivity (FPs@0.8) of 3.5754; this indicates a 6% improvement in MPTF and 16% reduction in FPs@0.8 compared to the state-of-the-art baseline model.Significance.From our experimental results, it can be observed that the anatomic-structure-based fusion of ipsilateral view information contributes significantly to the improvement of CADe model performance for atypical AD detection based on DBT. The proposed approach has the potential to lead to earlier diagnosis and better patient outcomes.


Asunto(s)
Neoplasias de la Mama , Mama , Humanos , Femenino , Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Mamografía/métodos , Simulación por Computador , Computadores
5.
Chem Commun (Camb) ; 59(66): 9980-9983, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37503825

RESUMEN

The mechanical properties of de-lithiated single-crystal Ni-rich cathodes are causing extensive concern. Here, we first show that the compression hardness of single crystal Ni-rich cathode particles decreases significantly at highly de-lithiated states by micro-compression testing. Thus, phase-boundary hardening was introduced to inhibit the planar gliding, resulting in excellent electrochemical performance.

6.
Plant J ; 114(4): 824-835, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36871136

RESUMEN

The formation of adventitious roots (ARs) derived from hypocotyl is the most important morphological adaptation to waterlogging stress in Cucumis sativus (cucumber). Our previous study showed that cucumbers with the gene CsARN6.1, encoding an AAA ATPase domain-containing protein, were more tolerant to waterlogging through increased AR formation. However, the apparent function of CsARN6.1 remained unknown. Here, we showed that the CsARN6.1 signal was predominantly observed throughout the cambium of hypocotyls, where de novo AR primordia are formed upon waterlogging treatment. The silencing of CsARN6.1 expression by virus-induced gene silencing and CRISPR/Cas9 technologies adversely affects the formation of ARs under conditions of waterlogging. Waterlogging treatment significantly induced ethylene production, thus upregulating CsEIL3 expression, which encodes a putative transcription factor involved in ethylene signaling. Furthermore, yeast one-hybrid, electrophoretic mobility assay and transient expression analyses showed that CsEIL3 binds directly to the CsARN6.1 promoter to initiate its expression. CsARN6.1 was found to interact with CsPrx5, a waterlogging-responsive class-III peroxidase that enhanced H2 O2 production and increased AR formation. These data provide insights into understanding the molecular mechanisms of AAA ATPase domain-containing protein and uncover a molecular mechanism that links ethylene signaling with the formation of ARs triggered by waterlogging.


Asunto(s)
Cucumis sativus , Cucumis sativus/genética , Cucumis sativus/metabolismo , Etilenos/metabolismo , Hipocótilo/metabolismo , Regulación de la Expresión Génica de las Plantas , ATPasas Asociadas con Actividades Celulares Diversas/genética , Raíces de Plantas/genética , Raíces de Plantas/metabolismo
7.
Phys Med Biol ; 68(4)2023 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-36595312

RESUMEN

Objective. In digital breast tomosynthesis (DBT), architectural distortion (AD) is a breast lesion that is difficult to detect. Compared with typical ADs, which have radial patterns, identifying a typical ADs is more difficult. Most existing computer-aided detection (CADe) models focus on the detection of typical ADs. This study focuses on atypical ADs and develops a deep learning-based CADe model with an adaptive receptive field in DBT.Approach. Our proposed model uses a Gabor filter and convergence measure to depict the distribution of fibroglandular tissues in DBT slices. Subsequently, two-dimensional (2D) detection is implemented using a deformable-convolution-based deep learning framework, in which an adaptive receptive field is introduced to extract global features in slices. Finally, 2D candidates are aggregated to form the three-dimensional AD detection results. The model is trained on 99 positive cases with ADs and evaluated on 120 AD-positive cases and 100 AD-negative cases.Main results. A convergence-measure-based model and deep-learning model without an adaptive receptive field are reproduced as controls. Their mean true positive fractions (MTPF) ranging from 0.05 to 4 false positives per volume are 0.3846 ± 0.0352 and 0.6501 ± 0.0380, respectively. Our proposed model achieves an MTPF of 0.7148 ± 0.0322, which is a significant improvement (p< 0.05) compared with the other two methods. In particular, our model detects more atypical ADs, primarily contributing to the performance improvement.Significance. The adaptive receptive field helps the model improve the atypical AD detection performance. It can help radiologists identify more ADs in breast cancer screening.


Asunto(s)
Neoplasias de la Mama , Mama , Humanos , Femenino , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/patología , Mamografía/métodos , Detección Precoz del Cáncer , Computadores
8.
Scand Cardiovasc J ; 56(1): 224-230, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35792722

RESUMEN

Background. Far-field electrograms from superior vena cava (SVC) can be present in right superior pulmonary vein (RSPV) after pulmonary vein (PV) isolation. Objectives. To analyze the characteristics of far-field SVC potentials in RSPV after PV isolation and the local anatomy difference between patients with and without the potentials. Methods. Patients undergoing PV isolation were retrospectively reviewed, contrast-enhanced computed tomography (CT) was performed before procedure for observing the anatomical relationship between RSPV and SVC. The prevalence and characteristics of far-field SVC electrograms were described and compared to far-field left atrial potentials at the nearest point along the linear ablation lesion. The anatomical proximity of RSPV and SVC on a 2-dimensional horizontal CT view was compared between patients with and without far-field SVC potentials. Results. Far-field SVC electrograms were observed in 35/92(38%) patients with an amplitude of 0.24 ± 0.11 mV and a major deflection slope of 0.051 ± 0.036 mV, both significantly higher than far-field left atrial electrograms (p < .001). In patients with far-field SVC electrograms, 83% had connected RSPV-SVC, defined as distance between RSPV and SVC endocardium less than 3 mm at the layer of RSPV ostium roof, while in patients without far-field SVC electrograms, 70% had disconnected RSPV-SVC. Conclusions. Far-field SVC electrograms appeared in RSPV had a prevalence higher than previously reported and a sharper major deflection compared to far-field left atrial electrograms. Connected RSPV-SVC on CT was associated with the presence of far-field SVC electrograms.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Venas Pulmonares , Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/cirugía , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Humanos , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/cirugía , Estudios Retrospectivos , Vena Cava Superior/diagnóstico por imagen , Vena Cava Superior/cirugía
9.
Acta Biomater ; 148: 218-229, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35705171

RESUMEN

Triple negative breast cancer (TNBC) is highly malignant and prone to recurrence and metastasis. Patients with TNBC usually have poor prognosis. Hence, it is urgent to develop new comprehensive treatments for TNBC. The combination of heat shock protein (HSP) inhibitor and the photothermal agent can reduce the temperature required to kill tumor cells, thus achieving mild-temperature photothermal therapy (PTT). Compared with traditional PTT, mild-temperature PTT not only decreases tumor thermoresistance introduced by the overexpression of HSP, but also reduces the damage to normal tissues. Meanwhile, Azo initiator 2,2-azobis[2-(2-imidazolin-2-yl) propane]-dihydroch-loride (AIPH) can be thermally decomposed to generate oxygen-independent free radicals. Herein, a new therapeutic multifunctional nanoplatform (M-17AAG-AIPH) by loading heat shock protein 90 (HSP90) inhibitor (17AAG) and AIPH incorporated into mesoporous polydopamine (MPDA) was successfully constructed for mild-temperature PTT combined with oxygen-independent cytotoxic free radicals against TNBC. Under 808 nm laser irradiation, the mild-temperature PTT arising from the combined effects of 17AAG and MPDA induced a rapid release and decomposition of AIPH, promoting the apoptosis of cancer cells in hypoxic microenvironments. Both in vitro and in vivo results showed that the designed nanoplatform can significantly inhibit tumor growth and provided an efficient new therapeutic strategy for TNBC. STATEMENT OF SIGNIFICANCE: There is still an urgent need for new strategies for the treatment of triple negative breast cancer (TNBC). In this work, we successfully constructed a new therapeutic multifunctional nanoplatform (M-17AAG-AIPH) by co-carrying heat shock protein 90 (HSP90) inhibitor (17AAG) and AIPH on mesoporous polydopamine (MPDA). MPDA owned good biocompatibility and outstanding photothermal-conversion ability. The loading of 17AAG can reduce the heat resistance of tumor cells via specifically inhibiting the activity of HSP90, so as to achieve mild-temperature PTT. Meanwhile, 17AAG and MPDA mediated mild-temperature PTT promoted the decomposition of AIPH into oxygen-independent cytotoxic free radicals. Both in vitro and in vivo results showed that M-17AAG-AIPH can significantly inhibit tumor growth and provided an efficient new therapeutic strategy for TNBC.


Asunto(s)
Antineoplásicos , Hipertermia Inducida , Nanopartículas , Neoplasias de la Mama Triple Negativas , Línea Celular Tumoral , Radicales Libres , Proteínas de Choque Térmico , Humanos , Hipertermia Inducida/métodos , Nanopartículas/química , Oxígeno , Fototerapia/métodos , Terapia Fototérmica , Temperatura , Neoplasias de la Mama Triple Negativas/terapia , Microambiente Tumoral
10.
Cell Biosci ; 12(1): 57, 2022 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-35526067

RESUMEN

BACKGROUND: B1 cells are self-renewing innate-like B lymphocytes that provide the first line of defense against pathogens. B1 cells primarily reside in the peritoneal cavity and are known to originate from various fetal tissues, yet their developmental pathways and the mechanisms underlying maintenance of B1 cells throughout adulthood remain unclear. RESULTS: We performed high-throughput single-cell analysis of the transcriptomes and B-cell receptor repertoires of peritoneal B cells of neonates, young adults, and elderly mice. Gene expression analysis of 31,718 peritoneal B cells showed that the neonate peritoneal cavity contained many B1 progenitors, and neonate B cell specific clustering revealed two trajectories of peritoneal B1 cell development, including pre-BCR dependent and pre-BCR independent pathways. We also detected profound age-related changes in B1 cell transcriptomes: clear difference in senescence genetic program was evident in differentially aged B1 cells, and we found an example that a B1 subset only present in the oldest mice was marked by expression of the fatty-acid receptor CD36. We also performed antibody gene sequencing of 15,967 peritoneal B cells from the three age groups and discovered that B1 cell aging was associated with clonal expansion and two B1 cell clones expanded in the aged mice had the same CDR-H3 sequence (AGDYDGYWYFDV) as a pathogenically linked cell type from a recent study of an atherosclerosis mouse model. CONCLUSIONS: Beyond offering an unprecedent data resource to explore the cell-to-cell variation in B cells, our study has revealed that B1 precursor subsets are present in the neonate peritoneal cavity and dissected the developmental pathway of the precursor cells. Besides, this study has found the expression of CD36 on the B1 cells in the aged mice. And the single-cell B-cell receptor sequencing reveals B1 cell aging is associated with clonal expansion.

12.
Plant Cell ; 33(3): 581-602, 2021 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-33955485

RESUMEN

Plants possess unique primary cell walls made of complex polysaccharides that play critical roles in determining intrinsic cell and organ size. How genes responsible for synthesizing and modifying the polysaccharides in the cell wall are regulated by microRNAs (miRNAs) to control plant size remains largely unexplored. Here we identified 23 putative cell wall-related miRNAs, termed as CW-miRNAs, in Arabidopsis thaliana and characterized miR775 as an example. We showed that miR775 post-transcriptionally silences GALT9, which encodes an endomembrane-located galactosyltransferase belonging to the glycosyltransferase 31 family. Over-expression of miR775 and deletion of GALT9 led to significantly enlarged leaf-related organs, primarily due to increased cell size. Monosaccharide quantification, confocal Raman imaging, and immunolabeling combined with atomic force microscopy revealed that the MIR775A-GALT9 circuit modulates pectin levels and the elastic modulus of the cell wall. We also showed that MIR775A is directly repressed by the transcription factor ELONGATED HYPOCOTYL5 (HY5). Genetic analysis confirmed that HY5 is a negative regulator of leaf size that acts through the HY5-MIR775A-GALT9 repression cascade to control pectin levels. These findings demonstrate that miR775-regulated cell wall remodeling is an integral determinant of intrinsic leaf size in A. thaliana. Studying other CW-miRNAs would provide more insights into cell wall biology.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Pared Celular/metabolismo , Galactosiltransferasas/metabolismo , Pectinas/metabolismo , Hojas de la Planta/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Proteínas de Arabidopsis/genética , Galactosiltransferasas/genética , Regulación de la Expresión Génica de las Plantas , Plantas Modificadas Genéticamente/genética
13.
J Stroke Cerebrovasc Dis ; 30(6): 105752, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33784518

RESUMEN

PURPOSE: To explore a new approach mainly based on deep learning residual network (ResNet) to detect infarct cores on non-contrast CT images and improve the accuracy of acute ischemic stroke diagnosis. METHODS: We continuously enrolled magnetic resonance diffusion weighted image (MR-DWI) confirmed first-episode ischemic stroke patients (onset time: less than 9 h) as well as some normal individuals in this study. They all underwent CT plain scan and MR-DWI scan with same scanning range, layer thickness (4 mm) and interlayer spacing (4 mm) (The time interval between two examinations: less than 4 h). Setting MR-DWI as gold standard of infarct core and using deep learning ResNet combined with a maximum a posteriori probability (MAP) model and a post-processing method to detect the infarct core on non-contrast CT images. After that, we use decision curve analysis (DCA) establishing models to analyze the value of this new method in clinical practice. RESULTS: 116 ischemic stroke patients and 26 normal people were enrolled. 58 patients were allocated into training dataset and 58 were divided into testing dataset along with 26 normal samples. The identification accuracy of our ResNet based approach in detecting the infarct core on non-contrast CT is 75.9%. The DCA shows that this deep learning method is capable of improving the net benefit of ischemic stroke patients. CONCLUSIONS: Our deep learning residual network assisted with optimization methods is able to detect early infarct core on non-contrast CT images and has the potential to help physicians improve diagnostic accuracy in acute ischemic stroke patients.


Asunto(s)
Infarto Encefálico/diagnóstico por imagen , Aprendizaje Profundo , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Estudios de Casos y Controles , Imagen de Difusión por Resonancia Magnética , Diagnóstico Precoz , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Interpretación de Imagen Radiográfica Asistida por Computador , Reproducibilidad de los Resultados
14.
Plant Cell ; 33(5): 1506-1529, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-33616669

RESUMEN

Light-dependent seed germination is a vital process for many seed plants. A decisive event in light-induced germination is degradation of the central repressor PHYTOCHROME INTERACTING FACTOR 1 (PIF1). The balance between gibberellic acid (GA) and abscisic acid (ABA) helps to control germination. However, the cellular mechanisms linking PIF1 turnover to hormonal balancing remain elusive. Here, employing far-red light-induced Arabidopsis thaliana seed germination as the experimental system, we identified PLANTACYANIN (PCY) as an inhibitor of germination. It is a blue copper protein associated with the vacuole that is both highly expressed in mature seeds and rapidly silenced during germination. Molecular analyses showed that PIF1 binds to the miR408 promoter and represses miR408 accumulation. This in turn posttranscriptionally modulates PCY abundance, forming the PIF1-miR408-PCY repression cascade for translating PIF1 turnover to PCY turnover during early germination. Genetic analysis, RNA-sequencing, and hormone quantification revealed that PCY is necessary and sufficient to maintain the PIF1-mediated seed transcriptome and the low-GA-high-ABA state. Furthermore, we found that PCY domain organization and regulation by miR408 are conserved features in seed plants. These results revealed a cellular mechanism whereby PIF1-relayed external light signals are converted through PCY turnover to internal hormonal profiles for controlling seed germination.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Germinación , Luz , Metaloproteínas/metabolismo , MicroARNs/metabolismo , Semillas/crecimiento & desarrollo , Transducción de Señal , Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Secuencia de Bases , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Secuencia Conservada , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Silenciador del Gen , Genes de Plantas , Germinación/genética , Giberelinas/metabolismo , MicroARNs/genética , Modelos Biológicos , Filogenia , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Unión Proteica/efectos de la radiación , Plantones/efectos de la radiación , Semillas/genética , Transducción de Señal/efectos de la radiación , Vacuolas/metabolismo , Vacuolas/efectos de la radiación
15.
Artículo en Inglés | MEDLINE | ID: mdl-32344851

RESUMEN

Ecosystem services (ESs) are facing challenges from urbanization processes globally. Exploring how ESs respond to urbanization provides valuable information for ecological protection and urban landscape planning. Previous studies mainly focused on the global and single-scaled responses of ESs but ignored the spatially heterogenous and scale-dependent characteristics of these responses. This study chose Wuhan City in China as the study area to explore the spatially varying and scale-dependent responses of ESs, i.e., grain productivity, carbon sequestration, biodiversity potential and erosion prevention, to urbanization using geographically weighted regression (GWR). The results showed that the responses of ESs were spatially nonstationary evidenced by a set of local parameter estimates in GWR models, and scale-dependent indicated by two kinds of scale effects: effect of different bandwidths and effect of grid scales. The stationary index of GWR declined rapidly as the bandwidth increased until reaching to a distance threshold. Moreover, GWR outperformed ordinary least square at both grid scales (i.e., 5 km and 10 km scales) and behaved better at finer scale. The spatially non-stationary and scale-dependent responses of ESs to urbanization are expected to provide beneficial guidance for ecologically friendly urban planning.


Asunto(s)
Ecosistema , Urbanización , China , Ciudades , Conservación de los Recursos Naturales/métodos , Humanos
16.
Front Plant Sci ; 11: 627331, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33643336

RESUMEN

Waterlogging is one of the main abiotic stresses suffered by plants. Inhibition of aerobic respiration during waterlogging limits energy metabolism and restricts growth and a wide range of developmental processes, from seed germination to vegetative growth and further reproductive growth. Plants respond to waterlogging stress by regulating their morphological structure, energy metabolism, endogenous hormone biosynthesis, and signaling processes. In this updated review, we systematically summarize the changes in morphological structure, photosynthesis, respiration, reactive oxygen species damage, plant hormone synthesis, and signaling cascades after plants were subjected to waterlogging stress. Finally, we propose future challenges and research directions in this field.

17.
3 Biotech ; 9(11): 390, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31656728

RESUMEN

The goal of this study was to provide quantitative data on the catechin contents and underlying molecular regulatory mechanisms in cucumber during fruit development. The dynamic changes in the total catechin contents and RNA-seq-based transcriptome profiling of the flesh and peel of the cucumber cultivar 'YanBai', which is strongly astringent, were examined at three key developmental stages 3, 6 and 9 days post-pollination. The total catechin content decreased as cucumber fruit developed and was significantly lower in the flesh than in the peel. In total, 5092 and 4004 genes were found to be differently expressed in the peel and flesh, respectively. Based on a functional annotation, eight structural genes encode enzymes involved in the catechin biosynthesis pathway. Three genes encoding 4-coumarate-CoA ligases, two genes encoding chalcone isomerases, two genes encoding dihydroflavonol-4-reductase and one gene each encoding a phenylalanine ammonia-lyase, flavanone 3-hydroxylase and cinnamate 4-hydroxylase were identified as affecting the catechin content of cucumber. The transcriptome data also revealed the significance of transcription factors, including WD40-repeat proteins, MYB and bHLH, in regulating catechin biosynthesis. These findings help increase our understanding of the molecular mechanisms controlling catechin biosynthesis and astringency development in cucumber fruit.

18.
Mol Biol Rep ; 46(6): 6381-6389, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31538299

RESUMEN

The formation of adventitious roots (ARs) is a key morphological adaptation of cucumber (Cucumis sativus L.) to waterlogging stress. MicroRNAs (miRNAs) constitute a group of non-coding small RNAs (sRNA) that play crucial roles in regulating diverse biological processes, including waterlogging acclimation. However, which specific miRNAs and how they are involved in waterlogging-triggered de novo AR primordia formation are not fully known. Here, Illumina sRNA sequencing was applied to sequence six sRNA libraries generated from the waterlogging-tolerant cucumber Zaoer-N after 48 h of waterlogging and the control. A total of 358 cucumber miRNAs, 312 known and 46 novel, were obtained. Among them, 23 were differentially expressed, with 10 and 13 being up- and downregulated, respectively. A qPCR expression study confirmed that the identified differentially expressed miRNAs were credible. A total of 657 putative miRNA target genes were predicted for the 23 miRNAs using an in silico approach. A gene ontology enrichment analysis revealed that target genes functioning in cell redox homeostasis, cytoskeleton, photosynthesis and cell growth were over-represented. In total, 58 of the 657 target genes showed inverse expression patterns compared with their respective miRNAs through a combined analysis of sRNA- and RNA-sequencing-based transcriptome datasets using the same experimental design. The target gene annotation included a peroxidase, a GDSL esterases/lipase and two heavy metal-associated isoprenylated plant proteins. Our results provide an important framework for understanding the unique miRNA patterns seen in responses to waterlogging and the miRNA-mediated formation of de novo AR primordia in cucumber.


Asunto(s)
Cucumis sativus/crecimiento & desarrollo , MicroARNs/genética , Análisis de Secuencia de ARN/métodos , Estrés Fisiológico , Cucumis sativus/genética , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica de las Plantas , Redes Reguladoras de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Proteínas de Plantas/genética , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , ARN de Planta/genética
19.
World Neurosurg ; 127: 266-268, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30981797

RESUMEN

BACKGROUND: The 2016 World Health Organization Classification of Tumours of the Central Nervous System was revised to include a new diagnostic entity, diffuse midline glioma, H3 K27M-mutant (DMG-K27M), a highly aggressive tumor with a mean survival time of 1 year after diagnosis. DMG-K27M is classified as a World Health Organization grade IV tumor regardless of histopathologic features, and there is currently no effective treatment for it despite ongoing research. CASE DESCRIPTION: We present a case of a 39-year-old man with a slow-growing thalamic glioma with histone H3 lysine 27-to-methionine mutation. This patient received surgical intervention 3 years after the initial discovery of the tumor. Because the patient did not receive any preoperative treatment for DMG-K27M, this case reflects 1 possible natural course of progression for this type of malignancy. CONCLUSIONS: There are currently no effective therapeutic options for treatment of DMG-K27M. The slow tumor growth and prolonged survival time (≥ 3 years) in the absence of intervention in this case serve as a reminder that much is still not known about histone H3 lysine 27-to-methionine mutation and how it impacts the pathophysiology, diagnosis, treatment, and prognosis of the disease. Careful evaluation is warranted to determine if early intervention is the best approach when treating DMG-K27M.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirugía , Glioma/genética , Glioma/cirugía , Histonas/genética , Mutación , Adulto , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Progresión de la Enfermedad , Glioma/diagnóstico por imagen , Glioma/patología , Humanos , Masculino , Tálamo
20.
J Integr Plant Biol ; 60(4): 323-340, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29330900

RESUMEN

The ability of a plant to produce grain, fruit, or forage depends ultimately on photosynthesis. There have been few attempts, however, to study microRNAs, which are a class of endogenous small RNAs post-transcriptionally programming gene expression, in relation to photosynthetic traits. We focused on miR408, one of the most conserved plant miRNAs, and overexpressed it in parallel in Arabidopsis, tobacco, and rice. The transgenic plants all exhibited increased copper content in the chloroplast, elevated abundance of plastocyanin, and an induction of photosynthetic genes. By means of gas exchange and optical spectroscopy analyses, we showed that higher expression of miR408 leads to enhanced photosynthesis through improving efficiency of irradiation utilization and the capacity for carbon dioxide fixation. Consequently, miR408 hyper-accumulating plants exhibited higher rate of vegetative growth. An enlargement of seed size was also observed in all three species overproducing miR408. Moreover, we conducted a 2-year-two-location field trial and observed miR408 overexpression in rice significantly increased yield, which was primarily attributed to an elevation in grain weight. Taken together, these results demonstrate that miR408 is a positive regulator of photosynthesis and that its genetic engineering is a promising route for enhancing photosynthetic performance and yield in diverse plants.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , MicroARNs/metabolismo , Fotosíntesis/genética , Semillas/crecimiento & desarrollo , Semillas/genética , Cloroplastos/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Oryza/genética , Plantas Modificadas Genéticamente , Plastocianina/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Nicotiana/genética
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