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1.
Plant J ; 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38972041

RESUMEN

Diurnal flower-opening time (DFOT), the time of spikelet opening during the day, is an important trait for hybrid rice (Oryza sativa L.) seed production. Hybrids between indica and japonica rice varieties have strong heterosis, but the parental lines usually have different, nonoverlapping DFOTs. This reduces the success of hybrid seed production in crosses between indica and japonica subspecies, thus hindering the utilization of indica and japonica inter-subspecies heterosis. However, little is known about the molecular mechanisms regulating DFOT in rice. Here, we obtained japonica rice lines with a DFOT 1.5 h earlier than the wild type by overexpressing OsMYC2, a gene encoding a key transcription factor in the jasmonate (JA) signaling pathway. OsMYC2 is activated by JA signaling and directly regulates the transcription of genes related to JA biosynthesis and cell wall metabolism. Overexpressing OsMYC2 led to significantly increased JA contents and decreased cellulose and hemicellulose contents in lodicule cells, as well as the softening of lodicule cell walls. This may facilitate the swelling of lodicules, resulting in early diurnal flower-opening. These results suggest that the OsMYC2-JA feedback loop regulates DFOT in rice via cell wall remodeling. These findings shed light on the understanding of regulatory mechanism of the DFOT of plants, which should promote the development of indica and japonica varieties suitable for hybrid rice breeding.

2.
Cell Rep Med ; : 101615, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38897205

RESUMEN

The clinical efficacy of neoadjuvant immunotherapy plus chemotherapy remains elusive in localized epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). Here, we report interim results of a Simon's two-stage design, phase 2 trial using neoadjuvant sintilimab with carboplatin and nab-paclitaxel in resectable EGFR-mutant NSCLC. All 18 patients undergo radical surgery, with one patient experiencing surgery delay. Fourteen patients exhibit confirmed radiological response, with 44% achieving major pathological response (MPR) and no pathological complete response (pCR). Similar genomic alterations are observed before and after treatment without influencing the efficacy of subsequent EGFR-tyrosine kinase inhibitors (TKIs) in vitro. Infiltration and T cell receptor (TCR) clonal expansion of CCR8+ regulatory T (Treg)hi/CXCL13+ exhausted T (Tex)lo cells define a subtype of EGFR-mutant NSCLC highly resistant to immunotherapy, with the phenotype potentially serving as a promising signature to predict immunotherapy efficacy. Informed circulating tumor DNA (ctDNA) detection in EGFR-mutant NSCLC could help identify patients nonresponsive to neoadjuvant immunochemotherapy. These findings provide supportive data for the utilization of neoadjuvant immunochemotherapy and insight into immune resistance in EGFR-mutant NSCLC.

3.
Cells ; 13(11)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38891020

RESUMEN

Improving the drought resistance of rice is of great significance for expanding the planting area and improving the stable yield of rice. In our previous work, we found that ROLLED AND ERECT LEAF1 (REL1) protein promoted enhanced tolerance to drought stress by eliminating reactive oxygen species (ROS) levels and triggering the abscisic acid (ABA) response. However, the mechanism through which REL1 regulates drought tolerance by removing ROS is unclear. In this study, we identified REL1 interacting protein 5 (RIP5) and found that it directly combines with REL1 in the chloroplast. We found that RIP5 was strongly expressed in ZH11 under drought-stress conditions, and that the rip5-ko mutants significantly improved the tolerance of rice plants to drought, whereas overexpression of RIP5 resulted in greater susceptibility to drought. Further investigation suggested that RIP5 negatively regulated drought tolerance in rice by decreasing the content of ascorbic acid (AsA), thereby reducing ROS clearance. RNA sequencing showed that the knockout of RIP5 caused differential gene expression that is chiefly associated with ascorbate and aldarate metabolism. Furthermore, multiple experimental results suggest that REL1 is involved in regulating drought tolerance by inhibiting RIP5. Collectively, our findings reveal the importance of the inhibition of RIP5 by REL1 in affecting the rice's response to drought stress. This work not only explains the drought tolerance mechanism of rice, but will also help to improve the drought tolerance of rice.


Asunto(s)
Sequías , Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Especies Reactivas de Oxígeno , Oryza/genética , Oryza/metabolismo , Oryza/fisiología , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Especies Reactivas de Oxígeno/metabolismo , Estrés Fisiológico , Ácido Abscísico/metabolismo , Cloroplastos/metabolismo , Adaptación Fisiológica/genética , Plantas Modificadas Genéticamente , Ácido Ascórbico/metabolismo , Unión Proteica , Resistencia a la Sequía
5.
Emerg Med J ; 41(6): 375-378, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38806201
6.
Nanotechnology ; 35(34)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38815566

RESUMEN

The formation of an asymmetric junction is key to graphene-based photodetectors of high-sensitive photodetectability, because such a junction can not only facilitate the diffusion or drift of photogenerated carriers but also realize a self-powered operation. Here, a monolayer-multilayer graphene junction photodetector is accomplished by selectively thinning part of a multilayer graphene to a high-quality monolayer. Benefiting from the large photoabsorption cross section of multilayer graphene and strong asymmetry caused by the significant differences in optoelectronic properties between monolayer and multilayer graphene, the monolayer-multilayer graphene junction shows a 7-fold increase in short-circuit photocurrent as compared with that at the monolayer graphene-metal contact in scanning photocurrent images. The asymmetric configuration also enables the photodetector to work at zero bias with minimized dark current noise and stand-by power consumption. Under global illumination with visible light, a photoswitching ratio of 3.4 × 103, a responsivity of 8.8 mA W-1, a specific detectivity of 1.3 × 108Jones and a response time of 11 ns can be obtained, suggesting a promising photoresponse. Moreover, it is worth mentioning that such a performance enhancement is achieved without compromising the broadband spectral response of graphene photodetector and it is hence applicable for long wavelength spectral range including infrared and terahertz.

7.
Water Sci Technol ; 89(9): 2342-2366, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747953

RESUMEN

To investigate the influence of carbonization process parameters on the characteristics of municipal sludge carbonization products, this study selected carbonization temperatures of 300-700 °C and carbonization times of 0.5-1.5 h to carbonize municipal sludge. The results showed that with an increase in temperature and carbonization time, the sludge was carbonized more completely, and the structure and performance characteristics of the sludge changed significantly. Organic matter was continuously cracked, the amorphous nature of the material was reduced, its morphology was transformed into an increasing number of regular crystalline structures, and the content of carbon continued to decrease, from the initial 52.85 to 38.77%, while the content of inorganic species consisting continued to increase. The conductivity was reduced by 87.8%, and the degree of conversion of salt ions into their residual and insoluble states was significant. Natural water absorption in the sludge decreased from 8.13 to 1.29%, and hydrophobicity increased. The dry-basis higher calorific value decreased from 8,703 to 3,574 kJ/kg. Heavy metals were concentrated by a factor of 2-3, but the content of the available state was very low. The results of this study provide important technological support for the selection of suitable carbonization process conditions and for resource utilization.


Asunto(s)
Carbono , Aguas del Alcantarillado , Temperatura , Aguas del Alcantarillado/química , Carbono/química , Eliminación de Residuos Líquidos/métodos , Factores de Tiempo , Metales Pesados/química
8.
Nat Commun ; 15(1): 2164, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38461306

RESUMEN

RNA splicing shapes the gene regulatory programs that underlie various physiological and disease processes. Here, we present the SCASL (single-cell clustering based on alternative splicing landscapes) method for interrogating the heterogeneity of RNA splicing with single-cell RNA-seq data. SCASL resolves the issue of biased and sparse data coverage on single-cell RNA splicing and provides a new scheme for classifications of cell identities. With previously published datasets as examples, SCASL identifies new cell clusters indicating potentially precancerous and early-tumor stages in triple-negative breast cancer, illustrates cell lineages of embryonic liver development, and provides fine clusters of highly heterogeneous tumor-associated CD4 and CD8 T cells with functional and physiological relevance. Most of these findings are not readily available via conventional cell clustering based on single-cell gene expression data. Our study shows the potential of SCASL in revealing the intrinsic RNA splicing heterogeneity and generating biological insights into the dynamic and functional cell landscapes in complex tissues.


Asunto(s)
Neoplasias , Empalme del ARN , Humanos , Empalme del ARN/genética , Empalme Alternativo/genética , Análisis de Secuencia de ARN/métodos
9.
Org Lett ; 26(12): 2495-2499, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38506235

RESUMEN

The selective functionalization of remote C-H bonds in free primary amines holds significant promise for the late-stage diversification of pharmaceuticals. However, to date, the direct functionalization of the meta position of amine substrates lacking additional directing groups remains underexplored. In this Letter, we present a successful meta-C-H arylation of free primary amine derivatives using aryl iodides, resulting in synthetically valuable yields. This meta-selective C-H functionalization is achieved through a sequence involving native amino-directed Pd-catalyzed seven-membered cyclometalation, followed by the utilization of a norbornene-type transient mediator.


Asunto(s)
Aminas , Paladio , Aminas/química , Paladio/química , Estructura Molecular , Catálisis , Norbornanos/química
11.
EMBO Mol Med ; 16(2): 334-360, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38177537

RESUMEN

Cancer immunotherapies have achieved unprecedented success in clinic, but they remain largely ineffective in some major types of cancer, such as colorectal cancer with microsatellite stability (MSS CRC). It is therefore important to study tumor microenvironment of resistant cancers for developing new intervention strategies. In this study, we identify a metabolic cue that determines the unique immune landscape of MSS CRC. Through secretion of distal cholesterol precursors, which directly activate RORγt, MSS CRC cells can polarize T cells toward Th17 cells that have well-characterized pro-tumor functions in colorectal cancer. Analysis of large human cancer cohorts revealed an asynchronous pattern of the cholesterol biosynthesis in MSS CRC, which is responsible for the abnormal accumulation of distal cholesterol precursors. Inhibiting the cholesterol biosynthesis enzyme Cyp51, by pharmacological or genetic interventions, reduced the levels of intratumoral distal cholesterol precursors and suppressed tumor progression through a Th17-modulation mechanism in preclinical MSS CRC models. Our study therefore reveals a novel mechanism of cancer-immune interaction and an intervention strategy for the difficult-to-treat MSS CRC.


Asunto(s)
Neoplasias Colorrectales , Inestabilidad de Microsatélites , Humanos , Neoplasias Colorrectales/genética , Microambiente Tumoral
12.
J Exp Med ; 221(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38047912

RESUMEN

T follicular helper (Tfh) cells, essential for germinal center reactions, are not identical, with different phenotypes reported. Whether, when, and how they generate memory cells is still poorly understood. Here, through single-cell RNA-sequencing analysis of CXCR5+Bcl6+ Tfh cells generated under different conditions, we discovered, in addition to PD-1hi effector Tfh cells, a CD62L+PD1low subpopulation. CD62L-expressing Tfh cells developed independently from PD-1+ cells and not in direct contact with B cells. More importantly, CD62L+ Tfh cells expressed memory- and stemness-associated genes, and with better superior long-term survival, they readily generated PD-1hi cells in the recall response. Finally, KLF2 and IL7R, also highly expressed by CD62L+ Tfh cells, were required to regulate their development. Our work thus demonstrates a novel Tfh memory-like cell subpopulation, which may benefit our understanding of immune responses and diseases.


Asunto(s)
Linfocitos B , Células T Auxiliares Foliculares , Centro Germinal , Fenotipo , Receptores CXCR5
13.
Nat Commun ; 14(1): 7930, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38040768

RESUMEN

Computational deconvolution with single-cell RNA sequencing data as reference is pivotal to interpreting spatial transcriptomics data, but the current methods are limited to cell-type resolution. Here we present Redeconve, an algorithm to deconvolute spatial transcriptomics data at single-cell resolution, enabling interpretation of spatial transcriptomics data with thousands of nuanced cell states. We benchmark Redeconve with the state-of-the-art algorithms on diverse spatial transcriptomics platforms and datasets and demonstrate the superiority of Redeconve in terms of accuracy, resolution, robustness, and speed. Application to a human pancreatic cancer dataset reveals cancer-clone-specific T cell infiltration, and application to lymph node samples identifies differential cytotoxic T cells between IgA+ and IgG+ spots, providing novel insights into tumor immunology and the regulatory mechanisms underlying antibody class switch.


Asunto(s)
Perfilación de la Expresión Génica , Transcriptoma , Humanos , Transcriptoma/genética , Algoritmos , Benchmarking , Isotipos de Inmunoglobulinas , Análisis de la Célula Individual
14.
Exploration (Beijing) ; 3(4): 20220052, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37933238

RESUMEN

Luminescence is an essential signal for many plants, insects, and marine organisms to attract the opposite sex, avoid predators, and so on. Most luminescent living organisms have ingenious optical structures which can help them get high luminescent performances. These remarkable and efficient structures have been formed by natural selection from long-time evolution. Researchers keenly observed the enhanced luminescence phenomena and studied how these phenomena happen in order to learn the characteristics of bio-photonics. In this review, we summarize the optical structures for enhancing luminescence and their applications. The structures are classified according to their different functions. We focus on how researchers use these biological inspirations to enhance different luminescence processes, such as chemiluminescence (CL), photoluminescence (PL), and electroluminescence (EL). It lays a foundation for further research on the applications of luminescence enhancement. Furthermore, we give examples of luminescence enhancement by bio-inspired structures in information encryption, biochemical detection, and light sources. These examples show that it is possible to use bio-inspired optical structures to solve complex problems in optical applications. Our work will provide guidance for research on biomimetic optics, micro- and nano-optical structures, and enhanced luminescence.

16.
Angew Chem Int Ed Engl ; 62(49): e202313537, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37857989

RESUMEN

Overall water splitting (OWS) using semiconductor photocatalysts is a promising method for solar fuel production. Achieving a high quantum efficiency is one of the most important prerequisites for photocatalysts to realize high solar-to-fuel efficiency. In a recent study (Nature 2020, 58, 411-414), a quantum efficiency of almost 100 % has been achieved in an aluminum-doped strontium titanate (SrTiO3 : Al) photocatalyst. Herein, using the SrTiO3 : Al as a model photocatalyst, we reveal the criteria for efficient photocatalytic water splitting by investigating the carrier dynamics through a comprehensive photoluminescence study. It is found that the Al doping suppresses the generation of Ti3+ recombination centers in SrTiO3 , the surface band bending facilitates charge separation, and the in situ photo-deposited Rh/Cr2 O3 and CoOOH co-catalysts render efficient charge extraction. By suppressing photocarrier recombination and establishing a facile charge separation and extraction mechanism, high quantum efficiency can be achieved even on photocatalysts with a very short (sub-ns) intrinsic photocarrier lifetime, challenging the belief that a long carrier lifetime is a fundamental requirement. Our findings could provide guidance on the design of OWS photocatalysts toward more efficient solar-to-fuel conversion.

17.
Phys Chem Chem Phys ; 25(37): 25850-25861, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37724976

RESUMEN

Alkyl sulfoxide groups were introduced into the branch chain terminals of a hole-transporting material (HTM) Z34 with different numbers and positions to design four new Y-shaped HTMs: ZT1, ZT2, ZT3 and ZT4. The effects of steric hindrance and number of substituents on the transfer and interface properties of the Y-shaped HTMs were investigated theoretically. Calculations reveal that the introduction of alkyl sulfoxide increases the distribution of intramolecular holes and orbital overlap between the HOMOs of the dimers. The electronic coupling was greatly improved owing to the increased distribution of holes and orbital overlap. ZT1 shows small steric hindrance when one alkyl sulfoxide is introduced into the top branch chain, which leads to translation π-π stacking. ZT2 and ZT4 show slightly greater steric hindrance when two or four alkyl sulfoxide groups are introduced into the side branch chains, which leads to face-to-face stacking. While ZT3 shows large steric hindrance when three alkyl sulfoxide groups are introduced into the top and side branch chains, which causes head-to-head stacking. With the increase in number of alkyl sulfoxide groups, the steric hindrance of the molecule increases and the hole mobility decreases. ZT1 achieves the highest hole mobility (2.63 × 10-2 m2 V-1 s-1) that is two orders of magnitude higher than that of Z34 (1.36 × 10-4 m2 V-1 s-1) owing to the optimal balance between the number of alkyl sulfoxide groups and steric hindrance. The HTM/CH3NH3PbI3 adsorbed system was also simulated to characterize the interface properties. Enhanced interface interaction was achieved in the HTM/perovskite systems of ZT2 and ZT3. The orbital distribution of the HTM/perovskite cluster indicates that the new HTMs can promote hole migration and prevent internal electron-hole recombination. The present work not only evaluates the reliable relationship between the structure and properties of new HTMs, but also provides a valuable design strategy for efficient Y-shaped HTMs.

18.
Genomics Proteomics Bioinformatics ; 21(5): 926-949, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37739168

RESUMEN

Over the past decade, advances in single-cell omics (SCO) technologies have enabled the investigation of cellular heterogeneity at an unprecedented resolution and scale, opening a new avenue for understanding human biology and disease. In this review, we summarize the developments of sequencing-based SCO technologies and computational methods, and focus on considerable insights acquired from SCO sequencing studies to understand normal and diseased properties, with a particular emphasis on cancer research. We also discuss the technological improvements of SCO and its possible contribution to fundamental research of the human, as well as its great potential in clinical diagnoses and personalized therapies of human disease.


Asunto(s)
Biología , Humanos
20.
Cell ; 186(19): 4235-4251.e20, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37607536

RESUMEN

Natural killer (NK) cells play indispensable roles in innate immune responses against tumor progression. To depict their phenotypic and functional diversities in the tumor microenvironment, we perform integrative single-cell RNA sequencing analyses on NK cells from 716 patients with cancer, covering 24 cancer types. We observed heterogeneity in NK cell composition in a tumor-type-specific manner. Notably, we have identified a group of tumor-associated NK cells that are enriched in tumors, show impaired anti-tumor functions, and are associated with unfavorable prognosis and resistance to immunotherapy. Specific myeloid cell subpopulations, in particular LAMP3+ dendritic cells, appear to mediate the regulation of NK cell anti-tumor immunity. Our study provides insights into NK-cell-based cancer immunity and highlights potential clinical utilities of NK cell subsets as therapeutic targets.


Asunto(s)
Células Asesinas Naturales , Neoplasias , Microambiente Tumoral , Humanos , Inmunidad Innata , Inmunoterapia , Células Asesinas Naturales/inmunología , Células Mieloides , Neoplasias/inmunología , Células Dendríticas/inmunología , Análisis de Expresión Génica de una Sola Célula
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