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1.
Cell ; 167(7): 1705-1718.e13, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27984722

RESUMO

Metformin has utility in cancer prevention and treatment, though the mechanisms for these effects remain elusive. Through genetic screening in C. elegans, we uncover two metformin response elements: the nuclear pore complex (NPC) and acyl-CoA dehydrogenase family member-10 (ACAD10). We demonstrate that biguanides inhibit growth by inhibiting mitochondrial respiratory capacity, which restrains transit of the RagA-RagC GTPase heterodimer through the NPC. Nuclear exclusion renders RagC incapable of gaining the GDP-bound state necessary to stimulate mTORC1. Biguanide-induced inactivation of mTORC1 subsequently inhibits growth through transcriptional induction of ACAD10. This ancient metformin response pathway is conserved from worms to humans. Both restricted nuclear pore transit and upregulation of ACAD10 are required for biguanides to reduce viability in melanoma and pancreatic cancer cells, and to extend C. elegans lifespan. This pathway provides a unified mechanism by which metformin kills cancer cells and extends lifespan, and illuminates potential cancer targets. PAPERCLIP.


Assuntos
Metformina/farmacologia , Acil-CoA Desidrogenase/genética , Envelhecimento , Animais , Tamanho Corporal , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Humanos , Longevidade , Alvo Mecanístico do Complexo 1 de Rapamicina , Mitocôndrias/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multiproteicos/metabolismo , Neoplasias/tratamento farmacológico , Poro Nuclear/metabolismo , Fosforilação Oxidativa , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fatores de Transcrição/metabolismo
2.
Nature ; 612(7940): 459-464, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36418403

RESUMO

High pressure represents extreme environments and provides opportunities for materials discovery1-8. Thermal transport under high hydrostatic pressure has been investigated for more than 100 years and all measurements of crystals so far have indicated a monotonically increasing lattice thermal conductivity. Here we report in situ thermal transport measurements in the newly discovered semiconductor crystal boron arsenide, and observe an anomalous pressure dependence of the thermal conductivity. We use ultrafast optics, Raman spectroscopy and inelastic X-ray scattering measurements to examine the phonon bandstructure evolution of the optical and acoustic branches, as well as thermal conductivity under varied temperatures and pressures up to 32 gigapascals. Using atomistic theory, we attribute the anomalous high-pressure behaviour to competitive heat conduction channels from interactive high-order anharmonicity physics inherent to the unique phonon bandstructure. Our study verifies ab initio theory calculations and we show that the phonon dynamics-resulting from competing three-phonon and four-phonon scattering processes-are beyond those expected from classical models and seen in common materials. This work uses high-pressure spectroscopy combined with atomistic theory as a powerful approach to probe complex phonon physics and provide fundamental insights for understanding microscopic energy transport in materials of extreme properties.

3.
Plant J ; 118(2): 534-548, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38230828

RESUMO

Citrus bacterial canker (CBC) is a serious bacterial disease caused by Xanthomonas citri subsp. citri (Xcc) that adversely impacts the global citrus industry. In a previous study, we demonstrated that overexpression of an Xcc-inducible apetala 2/ethylene response factor encoded by Citrus sinensis, CsAP2-09, enhances CBC resistance. The mechanism responsible for this effect, however, is not known. In the present study, we showed that CsAP2-09 targeted the promoter of the Xcc-inducible WRKY transcription factor coding gene CsWRKY25 directly, activating its transcription. CsWRKY25 was found to localize to the nucleus and to activate transcriptional activity. Plants overexpressing CsWRKY25 were more resistant to CBC and showed higher expression of the respiratory burst oxidase homolog (RBOH) CsRBOH2, in addition to exhibiting increased RBOH activity. Transient overexpression assays in citrus confirmed that CsWRKY25 and CsRBOH2 participated in the generation of reactive oxygen species (ROS) bursts, which were able to restore the ROS degradation caused by CsAP2-09 knockdown. Moreover, CsWRKY25 was found to bind directly to W-box elements within the CsRBOH2 promoter. Notably, CsRBOH2 knockdown had been reported previously to reduce the CBC resistance, while demonstrated in this study, CsRBOH2 transient overexpression can enhance the CBC resistance. Overall, our results outline a pathway through which CsAP2-09-CsWRKY25 transcriptionally reprograms CsRBOH2-mediated ROS homeostasis in a manner conducive to CBC resistance. These data offer new insight into the mechanisms and regulatory pathways through which CsAP2-09 regulates CBC resistance, highlighting its potential utility as a target for the breeding of CBC-resistant citrus varieties.


Assuntos
Citrus sinensis , Citrus , Xanthomonas , Citrus/genética , Citrus/microbiologia , Espécies Reativas de Oxigênio , Xanthomonas/genética , Melhoramento Vegetal , Citrus sinensis/genética , Citrus sinensis/microbiologia , Homeostase , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
4.
Hepatology ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900411

RESUMO

BACKGROUND AND AIMS: Surgical resection serves as the principal curative strategy for HCC, yet the incidence of postoperative recurrence remains alarmingly high. However, the spatial molecular structural alterations contributing to postoperative recurrence in HCC are still poorly understood. APPROACH AND RESULTS: We employed imaging mass cytometry to profile the in situ expression of 33 proteins within 358,729 single cells of 92 clinically annotated surgical specimens from 46 patients who were treated with surgical resections for primary and relapsed tumors. We revealed the recurrence progression of HCC was governed by the dynamic spatial distribution and functional interplay of diverse cell types across adjacent normal, tumor margin, and intratumor regions. Our exhaustive analyses revealed an aggressive, immunosuppression-related spatial ecosystem in relapsed HCC. Additionally, we illustrated the prominent implications of the tumor microenvironment of tumor margins in association with relapse HCC. Moreover, we identified a novel subpopulation of dendritic cells (PDL1 + CD103 + DCs) enriched in the peritumoral area that correlated with early postoperative recurrence, which was further validated in an external cohort. Through the analysis of single-cell RNA sequencing data, we found the interaction of PDL1 + CD103 + DCs with regulatory T cells and exhausted T cells enhanced immunosuppression and immune escape through multiple ligand-receptor pathways. CONCLUSIONS: We comprehensively depicted the spatial landscape of single-cell dynamics and multicellular architecture within primary and relapsed HCC. Our findings highlight spatial organization as a prominent determinant of HCC recurrence and provide valuable insight into the immune evasion mechanisms driving recurrence.

5.
FASEB J ; 38(15): e23850, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39091212

RESUMO

Atherosclerosis is a leading cause of cardiovascular diseases (CVDs), often resulting in major adverse cardiovascular events (MACEs), such as myocardial infarction and stroke due to the rupture or erosion of vulnerable plaques. Ferroptosis, an iron-dependent form of cell death, has been implicated in the development of atherosclerosis. Despite its involvement in CVDs, the specific role of ferroptosis in atherosclerotic plaque stability remains unclear. In this study, we confirmed the presence of ferroptosis in unstable atherosclerotic plaques and demonstrated that the ferroptosis inhibitor ferrostatin-1 (Fer-1) stabilizes atherosclerotic plaques in apolipoprotein E knockout (Apoe-/-) mice. Using bioinformatic analysis combining RNA sequencing (RNA-seq) with single-cell RNA sequencing (scRNA-seq), we identified Yes-associated protein 1 (YAP1) as a potential key regulator of ferroptosis in vascular smooth muscle cells (VSMCs) of unstable plaques. In vitro, we found that YAP1 protects against oxidized low-density lipoprotein (oxLDL)-induced ferroptosis in VSMCs. Mechanistically, YAP1 exerts its anti-ferroptosis effects by regulating the expression of glutaminase 1 (GLS1) to promote the synthesis of glutamate (Glu) and glutathione (GSH). These findings establish a novel mechanism where the inhibition of ferroptosis promotes the stabilization of atherosclerotic plaques through the YAP1/GLS1 axis, attenuating VSMC ferroptosis. Thus, targeting the YAP1/GLS1 axis to suppress VSMC ferroptosis may represent a novel strategy for preventing and treating unstable atherosclerotic plaques.


Assuntos
Ferroptose , Músculo Liso Vascular , Placa Aterosclerótica , Proteínas de Sinalização YAP , Animais , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Camundongos , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Proteínas de Sinalização YAP/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/genética , Camundongos Knockout , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Fenilenodiaminas/farmacologia , Cicloexilaminas/farmacologia , Apolipoproteínas E/metabolismo , Apolipoproteínas E/genética
6.
J Proteome Res ; 23(2): 653-662, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38170682

RESUMO

Cancer cells need a greater supply of glucose mainly due to their aerobic glycolysis, known as the Warburg effect. Glucose transport by glucose transporter 1 (GLUT1) is the rate-limiting step for glucose uptake, making it a potential cancer therapeutic target. However, GLUT1 is widely expressed and performs crucial functions in a variety of cells, and its indiscriminate inhibition will cause serious side effects. In this study, we designed and synthesized a photocaged GLUT1 inhibitor WZB117-PPG to suppress the growth of cancer cells in a spatiotemporally controllable manner. WZB117-PPG exhibited remarkable photolysis efficiency and substantial cytotoxicity toward cancer cells under visible light illumination with minimal side effects, ensuring its safety as a potential cancer therapy. Furthermore, our quantitative proteomics data delineated a comprehensive portrait of responses in cancer cells under glucose deprivation, underlining the mechanism of cell death via necrosis rather than apoptosis. We reason that our study provides a potentially reliable cancer treatment strategy and can be used as a spatiotemporally controllable trigger for studying nutrient deprivation-related stress responses.


Assuntos
Glucose , Hidroxibenzoatos , Neoplasias , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Preparações de Ação Retardada , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico
7.
Plant J ; 115(3): 742-757, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37095646

RESUMO

Root hair length (RHL) is an important character that affects nutrient acquisition in plants. The regulatory network in soybean controlling RHL is yet to be fully understood. In this study, we identified a quantitative trait locus (QTL) regulating RHL. One candidate causal gene in this QTL (GmbHLH113), preferentially expressed in root hairs, was annotated as encoding a basic helix-loop-helix transcription factor. In wild soybeans, the allelic type of GmbHLH113 with a glycine in the 13th residue, which was associated with a reduction in RHL, was shown to localize in the nucleus and activate gene transcription. Another allelic type with a single nucleotide polymorphism that resulted in a glutamate in the 13th residue is fixed in cultivated soybeans, and it lost the ability to localize to the nucleus or negatively regulate RHL. The ectopic expression of GmbHLH113 from W05 in Arabidopsis root hairs resulted in shorter RHL and reduced phosphorus (P) accumulation in shoots. Hence, a loss-of-function allele in cultivated soybeans might have been selected during domestication due to its association with a longer RHL and improved nutrient acquisition.


Assuntos
Arabidopsis , Glycine max , Glycine max/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Arabidopsis/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
8.
BMC Genomics ; 25(1): 475, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745120

RESUMO

BACKGROUND: Single nucleotide polymorphism (SNP) markers play significant roles in accelerating breeding and basic crop research. Several soybean SNP panels have been developed. However, there is still a lack of SNP panels for differentiating between wild and cultivated populations, as well as for detecting polymorphisms within both wild and cultivated populations. RESULTS: This study utilized publicly available resequencing data from over 3,000 soybean accessions to identify differentiating and highly conserved SNP and insertion/deletion (InDel) markers between wild and cultivated soybean populations. Additionally, a naturally occurring mutant gene library was constructed by analyzing large-effect SNPs and InDels in the population. CONCLUSION: The markers obtained in this study are associated with numerous genes governing agronomic traits, thus facilitating the evaluation of soybean germplasms and the efficient differentiation between wild and cultivated soybeans. The natural mutant gene library permits the quick identification of individuals with natural mutations in functional genes, providing convenience for accelerating soybean breeding using reverse genetics.


Assuntos
Glycine max , Mutação INDEL , Polimorfismo de Nucleotídeo Único , Glycine max/genética , Genoma de Planta , Biblioteca Gênica , Melhoramento Vegetal
9.
J Am Chem Soc ; 146(17): 11801-11810, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38626455

RESUMO

The direct double dehydrogenation from primary amines to nitriles without an oxidant or hydrogen acceptor is both intriguing and challenging. In this paper, we describe a non-noble metal catalyst capable of realizing such a transformation with high efficiency. A cobalt-centered N,N-bidentate complex was designed and employed as a metal-ligand cooperative dehydrogenation catalyst. Detailed kinetic studies, control experiments, and DFT calculations revealed the crucial hydride transfer, proton transfer, and hydrogen evolution processes. Finally, a tandem outer-sphere/inner-sphere mechanism was proposed for the dehydrogenation of amines to nitriles through an imine intermediate.

10.
J Am Chem Soc ; 146(14): 9631-9639, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38530981

RESUMO

The induced structural transformation provides an efficient way to precisely modulate the fine structures and the corresponding performance of gold nanoclusters, thus constituting one of the important research topics in cluster chemistry. However, the driving forces and mechanisms of these processes are still ambiguous in many cases, limiting further applications. In this work, based on the unique coordination mode of the pincer ligand-stabilized gold nanocluster Au8(PNP)4, we revealed the site-recognition mechanism for induced transformations of gold nanoclusters. The "open nitrogen sites" on the surface of the nanocluster interact with different inducers including organic compounds and metals and trigger the conversion of Au8(PNP)4 to Au13 and Au9Ag4 nanoclusters, respectively. Control experiments verified the site-recognition mechanism, and the femtosecond and nanosecond transient absorption spectroscopy revealed the electronic and photoluminescent evolution accompanied by the structural transformation.

11.
Mol Med ; 30(1): 124, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138413

RESUMO

BACKGROUND: Obesity is well-established as a significant contributor to the development of insulin resistance (IR) and diabetes, partially due to elevated plasma saturated free fatty acids like palmitic acid (PA). Grb10-interacting GYF Protein 2 (GIGYF2), an RNA-binding protein, is widely expressed in various tissues including the liver, and has been implicated in diabetes-induced cognitive impairment. Whereas, its role in obesity-related IR remains uninvestigated. METHODS: In this study, we employed palmitic acid (PA) exposure to establish an in vitro IR model in the human liver cancer cell line HepG2 with high-dose chronic PA treatment. The cells were stained with fluorescent dye 2-NBDG to evaluate cell glucose uptake. The mRNA expression levels of genes were determined by real-time qRT-PCR (RT-qPCR). Western blotting was employed to examine the protein expression levels. The RNA immunoprecipitation (RIP) was used to investigate the binding between protein and mRNA. Lentivirus-mediated gene knockdown and overexpression were employed for gene manipulation. In mice, an IR model induced by a high-fat diet (HFD) was established to validate the role and action mechanisms of GIGYF2 in the modulation of HFD-induced IR in vivo. RESULTS: In hepatocytes, high levels of PA exposure strongly trigger the occurrence of hepatic IR evidenced by reduced glucose uptake and elevated extracellular glucose content, which is remarkably accompanied by up-regulation of GIGYF2. Silencing GIGYF2 ameliorated PA-induced IR and enhanced glucose uptake. Conversely, GIGYF2 overexpression promoted IR, PTEN upregulation, and AKT inactivation. Additionally, PA-induced hepatic IR caused a notable increase in STAU1, which was prevented by depleting GIGYF2. Notably, silencing STAU1 prevented GIGYF2-induced PTEN upregulation, PI3K/AKT pathway inactivation, and IR. STAU1 was found to stabilize PTEN mRNA by binding to its 3'UTR. In liver cells, tocopherol treatment inhibits GIGYF2 expression and mitigates PA-induced IR. In the in vivo mice model, GIGYF2 knockdown and tocopherol administration alleviate high-fat diet (HFD)-induced glucose intolerance and IR, along with the suppression of STAU1/PTEN and restoration of PI3K/AKT signaling. CONCLUSIONS: Our study discloses that GIGYF2 mediates obesity-related IR by disrupting the PI3K/AKT signaling axis through the up-regulation of STAU1/PTEN. Targeting GIGYF2 may offer a potential strategy for treating obesity-related metabolic diseases, including type 2 diabetes.


Assuntos
Proteínas de Transporte , Resistência à Insulina , Fígado , PTEN Fosfo-Hidrolase , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Proteínas de Ligação a RNA , Transdução de Sinais , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Fosfatidilinositol 3-Quinases/metabolismo , Camundongos , Fígado/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Células Hep G2 , Ácido Palmítico , Masculino , Proteínas do Citoesqueleto/metabolismo , Proteínas do Citoesqueleto/genética , Camundongos Endogâmicos C57BL , Dieta Hiperlipídica/efeitos adversos
12.
Biochem Biophys Res Commun ; 710: 149882, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38583231

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease associated with type 2 diabetes mellitus (T2D). NAFLD can progress to nonalcoholic steatohepatitis (NASH), cirrhosis, and even cancer, all of which have a very poor prognosis. Semaglutide, a novel glucagon-like peptide-1 (GLP-1) receptor agonist, has been recognized as a specific drug for the treatment of diabetes. In this study, we used a gene mutation mouse model (db/db mice) to investigate the potential liver-improving effects of semaglutide. The results showed that semaglutide improved lipid levels and glucose metabolism in db/db mice. HE staining and oil red staining showed alleviation of liver damage and reduction of hepatic lipid deposition after injection of semaglutide. In addition, semaglutide also improved the integrity of gut barrier and altered gut microbiota, especially Alloprevotella, Alistpes, Ligilactobacillus and Lactobacillus. In summary, our findings validate that semaglutide induces modifications in the composition of the gut microbiota and ameliorates NAFLD, positioning it as a promising therapeutic candidate for addressing hepatic steatosis and associated inflammation.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Peptídeos Semelhantes ao Glucagon , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Fígado/metabolismo , Lipídeos/farmacologia , Camundongos Endogâmicos C57BL
13.
BMC Plant Biol ; 24(1): 326, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658809

RESUMO

BACKGROUND: Salt stress severely inhibits plant growth, and the WRKY family transcription factors play important roles in salt stress resistance. In this study, we aimed to characterize the role of tobacco (Nicotiana tabacum) NtWRKY65 transcription factor gene in salinity tolerance. RESULTS: This study characterized the role of tobacco (Nicotiana tabacum) NtWRKY65 transcription factor gene in salinity tolerance using four NtWRKY65 overexpression lines. NtWRKY65 is localized to the nucleus, has transactivation activity, and is upregulated by NaCl treatment. Salinity treatment resulted in the overexpressing transgenic tobacco lines generating significantly longer roots, with larger leaf area, higher fresh weight, and greater chlorophyll content than those of wild type (WT) plants. Moreover, the overexpressing lines showed elevated antioxidant enzyme activity, reduced malondialdehyde content, and leaf electrolyte leakage. In addition, the Na+ content significantly decreased, and the K+/Na+ ratio was increased in the NtWRKY65 overexpression lines compared to those in the WT. These results suggest that NtWRKY65 overexpression enhances salinity tolerance in transgenic plants. RNA-Seq analysis of the NtWRKY65 overexpressing and WT plants revealed that NtWRKY65 might regulate the expression of genes involved in the salt stress response, including cell wall component metabolism, osmotic stress response, cellular oxidant detoxification, protein phosphorylation, and the auxin signaling pathway. These results were consistent with the morphological and physiological data. These findings indicate that NtWRKY65 overexpression confers enhanced salinity tolerance. CONCLUSIONS: Our results indicated that NtWRKY65 is a critical regulator of salinity tolerance in tobacco plants.


Assuntos
Regulação da Expressão Gênica de Plantas , Nicotiana , Proteínas de Plantas , Plantas Geneticamente Modificadas , Tolerância ao Sal , Fatores de Transcrição , Nicotiana/genética , Nicotiana/fisiologia , Tolerância ao Sal/genética , Plantas Geneticamente Modificadas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
BMC Plant Biol ; 24(1): 749, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39103780

RESUMO

BACKGROUND: Climate change induces perturbation in the global water cycle, profoundly impacting water availability for agriculture and therefore global food security. Water stress encompasses both drought (i.e. water scarcity) that causes the drying of soil and subsequent plant desiccation, and flooding, which results in excess soil water and hypoxia for plant roots. Terrestrial plants have evolved diverse mechanisms to cope with soil water stress, with the root system serving as the first line of defense. The responses of roots to water stress can involve both structural and physiological changes, and their plasticity is a vital feature of these adaptations. Genetic methodologies have been extensively employed to identify numerous genetic loci linked to water stress-responsive root traits. This knowledge is immensely important for developing crops with optimal root systems that enhance yield and guarantee food security under water stress conditions. RESULTS: This review focused on the latest insights into modifications in the root system architecture and anatomical features of legume roots in response to drought and flooding stresses. Special attention was given to recent breakthroughs in understanding the genetic underpinnings of legume root development under water stress. The review also described various root phenotyping techniques and examples of their applications in different legume species. Finally, the prevailing challenges and prospective research avenues in this dynamic field as well as the potential for using root system architecture as a breeding target are discussed. CONCLUSIONS: This review integrated the latest knowledge of the genetic components governing the adaptability of legume roots to water stress, providing a reference for using root traits as the new crop breeding targets.


Assuntos
Mapeamento Cromossômico , Desidratação , Fabaceae , Fenótipo , Raízes de Plantas , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Fabaceae/genética , Fabaceae/fisiologia , Adaptação Fisiológica/genética , Secas , Inundações , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/fisiologia
15.
Small ; 20(9): e2305556, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37849043

RESUMO

Metal nanoclusters with precisely modulated structures at the nanoscale give us the opportunity to synthesize and investigate 1D nanomaterials at the atomic level. Herein, it realizes selective 1D growth of building block nanocluster "Au13 Cd2 " into three structurally different nanoclusters: "hand-in-hand" (Au13 Cd2 )2 O, "head-to-head" Au25 , and "shoulder-to-shoulder" Au33 . Detailed studies further reveals the growth mechanism and the growth-related tunable properties. This work provides new hints for the predictable structural transformation of nanoclusters and atomically precise construction of 1D nanomaterials.

16.
J Exp Bot ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820225

RESUMO

Citrus bacterial canker (CBC) is a disease that poses a major threat to global citrus production and is caused by infection with Xanthomonas citri subsp. citri (Xcc). Wall-associated receptor-like kinase (WAKL) proteins play an important role in shaping plant resistance to various bacterial and fungal pathogens. In a prior report, CsWAKL01 was identified as a candidate Xcc-inducible gene found to be upregulated in CBC-resistant citrus plants. However, the functional role of CsWAKL01 and the mechanisms whereby it may influence resistance to CBC have yet to be clarified. Here, CsWAKL01 was found to localize to the plasma membrane, and the overexpression of the corresponding gene in transgenic sweet oranges resulted in the pronounced enhancement of CBC resistance, whereas its knockdown had the opposite effect. Mechanistically, the ability of CsWAKL01 was linked to its ability to reprogram jasmonic acid, salicylic acid, and abscisic acid signaling activity. CsWRKY53 was further identified as a transcription factor capable of directly binding the CsWAKL01 promoter and inducing its transcriptional upregulation. CsWRKY53 silencing conferred greater CBC susceptibility to infected plants. Overall, these data support a model wherein CsWRKY53 functions as a positive regulator of CsWAKL01 to enhance resistance to CBC via the reprogramming of phytohormone signaling. Together these results offer new insight into the mechanisms whereby WAKLs shape phytopathogen resistance while underscoring the potential value of targeting the CsWRKY53-CsWAKL01 axis when seeking to breed CBC-resistant citrus plant varieties.

17.
Osteoporos Int ; 35(1): 117-128, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37670164

RESUMO

This study utilized deep learning to classify osteoporosis and predict bone density using opportunistic CT scans and independently tested the models on data from different hospitals and equipment. Results showed high accuracy and strong correlation with QCT results, showing promise for expanding osteoporosis screening and reducing unnecessary radiation and costs. PURPOSE: To explore the feasibility of using deep learning to establish a model for osteoporosis classification and bone density value prediction based on opportunistic CT scans and to verify its generalization and diagnostic ability using an independent test set. METHODS: A total of 1219 cases of opportunistic CT scans were included in this study, with QCT results as the reference standard. The training set: test set: independent test set ratio was 703: 176: 340, and the independent test set data of 340 cases were from 3 different hospitals and 4 different CT scanners. The VB-Net structure automatic segmentation model was used to segment the trabecular bone, and DenseNet was used to establish a three-classification model and bone density value prediction regression model. The performance parameters of the models were calculated and evaluated. RESULTS: The ROC curves showed that the mean AUCs of the three-category classification model for categorizing cases into "normal," "osteopenia," and "osteoporosis" for the training set, test set, and independent test set were 0.999, 0.970, and 0.933, respectively. The F1 score, accuracy, precision, recall, precision, and specificity of the test set were 0.903, 0.909, 0.899, 0.908, and 0.956, respectively, and those of the independent test set were 0.798, 0.815, 0.792, 0.81, and 0.899, respectively. The MAEs of the bone density prediction regression model in the training set, test set, and independent test set were 3.15, 6.303, and 10.257, respectively, and the RMSEs were 4.127, 8.561, and 13.507, respectively. The R-squared values were 0.991, 0.962, and 0.878, respectively. The Pearson correlation coefficients were 0.996, 0.981, and 0.94, respectively, and the p values were all < 0.001. The predicted values and bone density values were highly positively correlated, and there was a significant linear relationship. CONCLUSION: Using deep learning neural networks to process opportunistic CT scan images of the body can accurately predict bone density values and perform bone density three-classification diagnosis, which can reduce the radiation risk, economic consumption, and time consumption brought by specialized bone density measurement, expand the scope of osteoporosis screening, and have broad application prospects.


Assuntos
Doenças Ósseas Metabólicas , Aprendizado Profundo , Osteoporose , Humanos , Densidade Óssea , Osteoporose/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos
18.
Exp Dermatol ; 33(7): e15142, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39032085

RESUMO

Frequent itching and incessant scratching are commonly observed in various chronic inflammatory skin conditions, including atopic dermatitis and psoriasis. The persistent and prolonged nature of pruritus can worsen one's quality of life. Keratinocytes (KCs), the predominant cells of the epidermis, have been confirmed to interact with sensory neurons and immune cells and be involved in chronic skin inflammatory diseases associated with pruritus. Initially, KCs and sensory neurons form a unique synapse-like connection within the epidermis, serving as the structural foundation for their interaction. Additionally, several receptors, including toll-like receptors and protease-activated receptor 2, expressed on KCs, become activated in an inflammatory milieu. On the one hand, activated KCs are sources of pro-inflammatory cytokines and neurotrophic factors, such as adenosine triphosphate, thymic stromal lymphopoietin, and nerve growth factor, which directly or indirectly participate in stimulating sensory neurons, thereby contributing to the itch sensations. On the other hand, KCs also function as primary transducers alongside intraepidermal nerve endings, directly initiating pruritic responses. This review summarizes the current literature and highlights the critical role of KCs in the development and persistence of chronic itch in inflammatory skin disorders.


Assuntos
Queratinócitos , Prurido , Humanos , Prurido/etiologia , Prurido/fisiopatologia , Queratinócitos/metabolismo , Doença Crônica , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/fisiologia , Dermatite Atópica/complicações , Animais , Citocinas/metabolismo , Psoríase/complicações
19.
Int Arch Allergy Immunol ; 185(7): 718-728, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38513629

RESUMO

INTRODUCTION: The purpose of this study was to assess the clinical effectiveness and safety profile of omalizumab as a therapeutic intervention for chronic urticaria (CU). METHODS: From March 1, 2023, to September 30, 2023, data on a cohort comprising 96 patients with CU, who underwent treatment with omalizumab at our medical institution's allergy clinic, were systematically compiled. Subsequent to the administration of omalizumab, the therapeutic efficacy was assessed utilizing the 7-day urticaria activity score and the urticaria control test. RESULTS: Based on the statistical analysis, the mean duration of therapeutic intervention was 2.4 ± 1.3 months, with a corresponding mean cumulative dosage of 765 ± 450 mg. Of the subset of 42 patients with CU who were subjected to a follow-up period exceeding 3 months, it was observed that the treatment led to complete symptom remission, and no instances of recurrence were documented. Notably, there were statistically significant differences in the treatment duration and the cumulative dosage between patients who experienced co-morbid conditions and those who did not (p < 0.01, 95% CI: 0.280-1.326; p < 0.01, 95% CI: 0.597-2.997). Furthermore, there were significant differences in the treatment duration and cumulative dosage between patients in the combined allergic rhinitis group and those in the non-combined allergic rhinitis group (p < 0.01, 95% CI: 0.204-1.305; p = 0.01, 95% CI: 0.326-2.860). CONCLUSION: Omalizumab demonstrates efficacy in the management of CU among Chinese patients by exerting effective symptom control and facilitating the regression of skin lesions. The assessment of its therapeutic efficacy typically requires a 12-week treatment period. Moreover, the co-occurrence of CU with other allergic disorders serves as a pertinent consideration for the adjustment of omalizumab dosing regimens.


Assuntos
Antialérgicos , Urticária Crônica , Omalizumab , Humanos , Omalizumab/uso terapêutico , Urticária Crônica/tratamento farmacológico , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Resultado do Tratamento , Antialérgicos/uso terapêutico , Adulto Jovem
20.
Synapse ; 78(4): e22304, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38896000

RESUMO

The goal of this report is to explore how K2P channels modulate axonal excitability by using the crayfish ventral superficial flexor preparation. This preparation allows for simultaneous recording of motor nerve extracellular action potentials (eAP) and intracellular excitatory junctional potential (EJP) from a muscle fiber. Previous pharmacological studies have demonstrated the presence of K2P-like channels in crayfish. Fluoxetine (50 µM) was used to block K2P channels in this study. The blocker caused a gradual decline, and eventually complete block, of motor axon action potentials. At an intermediate stage of the block, when the peak-to-peak amplitude of eAP decreased to ∼60%-80% of the control value, the amplitude of the initial positive component of eAP declined at a faster rate than that of the negative peak representing sodium influx. Furthermore, the second positive peak following this sodium influx, which corresponds to the after-hyperpolarizing phase of intracellularly recorded action potentials (iAP), became larger during the intermediate stage of eAP block. Finally, EJP recorded simultaneously with eAP showed no change in amplitude, but did show a significant increase in synaptic delay. These changes in eAP shape and EJP delay are interpreted as the consequence of depolarized resting membrane potential after K2P channel block. In addition to providing insights to possible functions of K2P channels in unmyelinated axons, results presented here also serve as an example of how changes in eAP shape contain information that can be used to infer alterations in intracellular events. This type of eAP-iAP cross-inference is valuable for gaining mechanistic insights here and may also be applicable to other model systems.


Assuntos
Potenciais de Ação , Astacoidea , Axônios , Fluoxetina , Neurônios Motores , Animais , Astacoidea/efeitos dos fármacos , Astacoidea/fisiologia , Fluoxetina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Axônios/efeitos dos fármacos , Axônios/fisiologia
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