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1.
Cell ; 183(1): 258-268.e12, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32860739

RESUMEN

Plasmodium species, the causative agent of malaria, rely on glucose for energy supply during blood stage. Inhibition of glucose uptake thus represents a potential strategy for the development of antimalarial drugs. Here, we present the crystal structures of PfHT1, the sole hexose transporter in the genome of Plasmodium species, at resolutions of 2.6 Å in complex with D-glucose and 3.7 Å with a moderately selective inhibitor, C3361. Although both structures exhibit occluded conformations, binding of C3361 induces marked rearrangements that result in an additional pocket. This inhibitor-binding-induced pocket presents an opportunity for the rational design of PfHT1-specific inhibitors. Among our designed C3361 derivatives, several exhibited improved inhibition of PfHT1 and cellular potency against P. falciparum, with excellent selectivity to human GLUT1. These findings serve as a proof of concept for the development of the next-generation antimalarial chemotherapeutics by simultaneously targeting the orthosteric and allosteric sites of PfHT1.


Asunto(s)
Proteínas de Transporte de Monosacáridos/ultraestructura , Plasmodium falciparum/metabolismo , Plasmodium falciparum/ultraestructura , Proteínas Protozoarias/ultraestructura , Secuencia de Aminoácidos , Animales , Antimaláricos , Transporte Biológico , Glucosa/metabolismo , Humanos , Malaria , Malaria Falciparum/parasitología , Proteínas de Transporte de Monosacáridos/química , Proteínas de Transporte de Monosacáridos/metabolismo , Parásitos , Plasmodium falciparum/genética , Proteínas Protozoarias/química , Proteínas Protozoarias/metabolismo , Azúcares/metabolismo
2.
Nature ; 610(7930): 182-189, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36131013

RESUMEN

Most current therapies that target plasma membrane receptors function by antagonizing ligand binding or enzymatic activities. However, typical mammalian proteins comprise multiple domains that execute discrete but coordinated activities. Thus, inhibition of one domain often incompletely suppresses the function of a protein. Indeed, targeted protein degradation technologies, including proteolysis-targeting chimeras1 (PROTACs), have highlighted clinically important advantages of target degradation over inhibition2. However, the generation of heterobifunctional compounds binding to two targets with high affinity is complex, particularly when oral bioavailability is required3. Here we describe the development of proteolysis-targeting antibodies (PROTABs) that tether cell-surface E3 ubiquitin ligases to transmembrane proteins, resulting in target degradation both in vitro and in vivo. Focusing on zinc- and ring finger 3 (ZNRF3), a Wnt-responsive ligase, we show that this approach can enable colorectal cancer-specific degradation. Notably, by examining a matrix of additional cell-surface E3 ubiquitin ligases and transmembrane receptors, we demonstrate that this technology is amendable for 'on-demand' degradation. Furthermore, we offer insights on the ground rules governing target degradation by engineering optimized antibody formats. In summary, this work describes a strategy for the rapid development of potent, bioavailable and tissue-selective degraders of cell-surface proteins.


Asunto(s)
Anticuerpos , Especificidad de Anticuerpos , Proteínas de la Membrana , Proteolisis , Ubiquitina-Proteína Ligasas , Animales , Anticuerpos/inmunología , Anticuerpos/metabolismo , Neoplasias Colorrectales/metabolismo , Ligandos , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Receptores de Superficie Celular/inmunología , Receptores de Superficie Celular/metabolismo , Especificidad por Sustrato , Ubiquitina-Proteína Ligasas/inmunología , Ubiquitina-Proteína Ligasas/metabolismo
3.
Mol Cell ; 73(3): 458-473.e7, 2019 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-30581148

RESUMEN

Cholesterol is highly enriched at the plasma membrane (PM), and lipid transfer proteins may deliver cholesterol to the PM in a nonvesicular manner. Here, through a mini-screen, we identified the oxysterol binding protein (OSBP)-related protein 2 (ORP2) as a novel mediator of selective cholesterol delivery to the PM. Interestingly, ORP2-mediated enrichment of PM cholesterol was coupled with the removal of phosphatidylinositol 4, 5-bisphosphate (PI(4,5)P2) from the PM. ORP2 overexpression or deficiency impacted the levels of PM cholesterol and PI(4,5)P2, and ORP2 efficiently transferred both cholesterol and PI(4,5)P2in vitro. We determined the structure of ORP2 in complex with PI(4,5)P2 at 2.7 Å resolution. ORP2 formed a stable tetramer in the presence of PI(4,5)P2, and tetramerization was required for ORP2 to transfer PI(4,5)P2. Our results identify a novel pathway for cholesterol delivery to the PM and establish ORP2 as a key regulator of both cholesterol and PI(4,5)P2 of the PM.


Asunto(s)
Membrana Celular/metabolismo , Colesterol/metabolismo , Hepatocitos/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Receptores de Esteroides/metabolismo , Transporte Biológico , Línea Celular Tumoral , Células HEK293 , Humanos , Modelos Moleculares , Multimerización de Proteína , Estructura Cuaternaria de Proteína , Receptores de Esteroides/química , Receptores de Esteroides/genética , Relación Estructura-Actividad
4.
Circ Res ; 134(1): 60-80, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-38084631

RESUMEN

BACKGROUND: Increasing evidence suggests that long noncoding RNAs play significant roles in vascular biology and disease development. One such long noncoding RNA, PSMB8-AS1, has been implicated in the development of tumors. Nevertheless, the precise role of PSMB8-AS1 in cardiovascular diseases, particularly atherosclerosis, has not been thoroughly elucidated. Thus, the primary aim of this investigation is to assess the influence of PSMB8-AS1 on vascular inflammation and the initiation of atherosclerosis. METHODS: We generated PSMB8-AS1 knockin and Apoe (Apolipoprotein E) knockout mice (Apoe-/-PSMB8-AS1KI) and global Apoe and proteasome subunit-ß type-9 (Psmb9) double knockout mice (Apoe-/-Psmb9-/-). To explore the roles of PSMB8-AS1 and Psmb9 in atherosclerosis, we fed the mice with a Western diet for 12 weeks. RESULTS: Long noncoding RNA PSMB8-AS1 is significantly elevated in human atherosclerotic plaques. Strikingly, Apoe-/-PSMB8-AS1KI mice exhibited increased atherosclerosis development, plaque vulnerability, and vascular inflammation compared with Apoe-/- mice. Moreover, the levels of VCAM1 (vascular adhesion molecule 1) and ICAM1 (intracellular adhesion molecule 1) were significantly upregulated in atherosclerotic lesions and serum of Apoe-/-PSMB8-AS1KI mice. Consistently, in vitro gain- and loss-of-function studies demonstrated that PSMB8-AS1 induced monocyte/macrophage adhesion to endothelial cells and increased VCAM1 and ICAM1 levels in a PSMB9-dependent manner. Mechanistic studies revealed that PSMB8-AS1 induced PSMB9 transcription by recruiting the transcription factor NONO (non-POU domain-containing octamer-binding protein) and binding to the PSMB9 promoter. PSMB9 (proteasome subunit-ß type-9) elevated VCAM1 and ICAM1 expression via the upregulation of ZEB1 (zinc finger E-box-binding homeobox 1). Psmb9 deficiency decreased atherosclerotic lesion size, plaque vulnerability, and vascular inflammation in Apoe-/- mice in vivo. Importantly, endothelial overexpression of PSMB8-AS1-increased atherosclerosis and vascular inflammation were attenuated by Psmb9 knockout. CONCLUSIONS: PSMB8-AS1 promotes vascular inflammation and atherosclerosis via the NONO/PSMB9/ZEB1 axis. Our findings support the development of new long noncoding RNA-based strategies to counteract atherosclerotic cardiovascular disease.


Asunto(s)
Aterosclerosis , Placa Aterosclerótica , ARN Largo no Codificante , Animales , Humanos , Ratones , Apolipoproteínas E/genética , Aterosclerosis/metabolismo , Células Endoteliales/metabolismo , Inflamación/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Placa Aterosclerótica/patología , Complejo de la Endopetidasa Proteasomal/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
5.
Proc Natl Acad Sci U S A ; 120(6): e2221637120, 2023 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-36716376

RESUMEN

Lipids establish the specialized thylakoid membrane of chloroplast in eukaryotic photosynthetic organisms, while the molecular basis of lipid transfer from other organelles to chloroplast remains further elucidation. Here we revealed the structural basis of Arabidopsis Sec14 homology proteins AtSFH5 and AtSFH7 in transferring phosphatidic acid (PA) from endoplasmic reticulum (ER) to chloroplast, and whose function in regulating the lipid composition of chloroplast and thylakoid development. AtSFH5 and AtSFH7 localize at both ER and chloroplast, whose deficiency resulted in an abnormal chloroplast structure and a decreased thickness of stacked thylakoid membranes. We demonstrated that AtSFH5, but not yeast and human Sec14 proteins, could specifically recognize and transfer PA in vitro. Crystal structures of the AtSFH5-Sec14 domain in complex with L-α-phosphatidic acid (L-α-PA) and 1,2-dipalmitoyl-sn-glycero-3-phosphate (DPPA) revealed that two PA ligands nestled in the central cavity with different configurations, elucidating the specific binding mode of PA to AtSFH5, different from the reported phosphatidylethanolamine (PE)/phosphatidylcholine (PC)/phosphatidylinositol (PI) binding modes. Quantitative lipidomic analysis of chloroplast lipids showed that PA and monogalactosyldiacylglycerol (MGDG), particularly the C18 fatty acids at sn-2 position in MGDG were significantly decreased, indicating a disrupted ER-to-plastid (chloroplast) lipid transfer, under deficiency of AtSFH5 and AtSFH7. Our studies identified the role and elucidated the structural basis of plant SFH proteins in transferring PA between organelles, and suggested a model for ER-chloroplast interorganelle phospholipid transport from inherent ER to chloroplast derived from endosymbiosis of a cyanobacteriumproviding a mechanism involved in the adaptive evolution of cellular plastids.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Cloroplastos , Ácidos Fosfatidicos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , Ácidos Fosfatidicos/metabolismo , Tilacoides/metabolismo
6.
Development ; 149(10)2022 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-35502748

RESUMEN

Adventitious roots (ARs) are an important type of plant root and display high phenotypic plasticity in response to different environmental stimuli. It is known that photoreceptors inhibit darkness-induced hypocotyl adventitious root (HAR) formation by directly stabilizing Aux/IAA proteins. In this study, we further report that phytochrome-interacting factors (PIFs) plays a central role in HAR initiation by simultaneously inducing the expression of genes involved in auxin biosynthesis, auxin transport and the transcriptional control of root primordium initiation. We found that, on the basis of their activity downstream of phytochrome, PIFs are required for darkness-induced HAR formation. Specifically, PIFs directly bind to the promoters of some genes involved in root formation, including auxin biosynthesis genes YUCCA2 (YUC2) and YUC6, the auxin influx carrier genes AUX1 and LAX3, and the transcription factors WOX5/7 and LBD16/29, to activate their expression. These findings reveal a previously uncharacterized transcriptional regulatory network underlying HAR formation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Hipocótilo/genética , Hipocótilo/metabolismo , Ácidos Indolacéticos/metabolismo , Fitocromo/genética , Raíces de Plantas/genética , Raíces de Plantas/metabolismo
7.
Plant Physiol ; 195(2): 1642-1659, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38431524

RESUMEN

Maize (Zea mays) smut is a common biotrophic fungal disease caused by Ustilago maydis and leads to low maize yield. Maize resistance to U. maydis is a quantitative trait. However, the molecular mechanism underlying the resistance of maize to U. maydis is poorly understood. Here, we reported that a maize mutant caused by a single gene mutation exhibited defects in both fungal resistance and plant development. maize mutant highly susceptible to U. maydis (mmsu) with a dwarf phenotype forms tumors in the ear. A map-based cloning and allelism test demonstrated that 1 gene encoding a putative arogenate dehydratase/prephenate dehydratase (ADT/PDT) is responsible for the phenotypes of the mmsu and was designated as ZmADT2. Combined transcriptomic and metabolomic analyses revealed that mmsu had substantial differences in multiple metabolic pathways in response to U. maydis infection compared with the wild type. Disruption of ZmADT2 caused damage to the chloroplast ultrastructure and function, metabolic flux redirection, and reduced the amounts of salicylic acid (SA) and lignin, leading to susceptibility to U. maydis and dwarf phenotype. These results suggested that ZmADT2 is required for maintaining metabolic flux, as well as resistance to U. maydis and plant development in maize. Meanwhile, our findings provided insights into the maize response mechanism to U. maydis infection.


Asunto(s)
Resistencia a la Enfermedad , Enfermedades de las Plantas , Zea mays , Zea mays/microbiología , Zea mays/genética , Zea mays/crecimiento & desarrollo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Resistencia a la Enfermedad/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Hidroliasas/genética , Hidroliasas/metabolismo , Basidiomycota/fisiología , Regulación de la Expresión Génica de las Plantas , Fenotipo , Mutación/genética , Ácido Salicílico/metabolismo , Ustilago/genética
8.
EMBO Rep ; 24(1): e55542, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36394374

RESUMEN

The Zn content in cereal seeds is an important trait for crop production as well as for human health. However, little is known about how Zn is loaded to plant seeds. Here, through a genome-wide association study (GWAS), we identify the Zn-NA (nicotianamine) transporter gene ZmYSL2 that is responsible for loading Zn to maize kernels. High promoter sequence variation in ZmYSL2 most likely drives the natural variation in Zn concentrations in maize kernels. ZmYSL2 is specifically localized on the plasma membrane facing the maternal tissue of the basal endosperm transfer cell layer (BETL) and functions in loading Zn-NA into the BETL. Overexpression of ZmYSL2 increases the Zn concentration in the kernels by 31.6%, which achieves the goal of Zn biofortification of maize. These findings resolve the mystery underlying the loading of Zn into plant seeds, providing an efficient strategy for breeding or engineering maize varieties with enriched Zn nutrition.


Asunto(s)
Estudio de Asociación del Genoma Completo , Zea mays , Humanos , Zea mays/genética , Zea mays/metabolismo , Zinc/metabolismo , Fitomejoramiento , Semillas/genética , Proteínas de Transporte de Membrana/genética
9.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-37991271

RESUMEN

Neuroimaging markers for risk and protective factors related to type 2 diabetes mellitus are critical for clinical prevention and intervention. In this work, the individual metabolic brain networks were constructed with Jensen-Shannon divergence for 4 groups (elderly type 2 diabetes mellitus and healthy controls, and middle-aged type 2 diabetes mellitus and healthy controls). Regional network properties were used to identify hub regions. Rich-club, feeder, and local connections were subsequently obtained, intergroup differences in connections and correlations between them and age (or fasting plasma glucose) were analyzed. Multinomial logistic regression was performed to explore effects of network changes on the probability of type 2 diabetes mellitus. The elderly had increased rich-club and feeder connections, and decreased local connection than the middle-aged among type 2 diabetes mellitus; type 2 diabetes mellitus had decreased rich-club and feeder connections than healthy controls. Protective factors including glucose metabolism in triangle part of inferior frontal gyrus, metabolic connectivity between triangle of the inferior frontal gyrus and anterior cingulate cortex, degree centrality of putamen, and risk factors including metabolic connectivities between triangle of the inferior frontal gyrus and Heschl's gyri were identified for the probability of type 2 diabetes mellitus. Metabolic interactions among critical brain regions increased in type 2 diabetes mellitus with aging. Individual metabolic network changes co-affected by type 2 diabetes mellitus and aging were identified as protective and risk factors for the likelihood of type 2 diabetes mellitus, providing guiding evidence for clinical interventions.


Asunto(s)
Diabetes Mellitus Tipo 2 , Persona de Mediana Edad , Anciano , Humanos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Factores de Riesgo , Envejecimiento , Redes y Vías Metabólicas
10.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-38037387

RESUMEN

Previous studies have suggested that ischemic stroke can result in white matter fiber injury and modifications in the structural brain network. However, the relationship with balance function scores remains insufficiently explored. Therefore, this study aims to explore the alterations in the microstructural properties of brain white matter and the topological characteristics of the structural brain network in postischemic stroke patients and their potential correlations with balance function. We enrolled 21 postischemic stroke patients and 21 age, sex, and education-matched healthy controls (HC). All participants underwent balance function assessment and brain diffusion tensor imaging. Tract-based spatial statistics (TBSS) were used to compare the fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity of white matter fibers between the two groups. The white matter structural brain network was constructed based on the automated anatomical labeling atlas, and we conducted a graph theory-based analysis of its topological properties, including global network properties and local node properties. Additionally, the correlation between the significant structural differences and balance function score was analyzed. The TBSS results showed that in comparison to the HC, postischemic stroke patients exhibited extensive damage to their whole-brain white matter fiber tracts (P < 0.05). Graph theory analysis showed that in comparison to the HC, postischemic stroke patients exhibited statistically significant reductions in the values of global efficiency, local efficiency, and clustering coefficient, as well as an increase in characteristic path length (P < 0.05). In addition, the degree centrality and nodal efficiency of some nodes in postischemic stroke patients were significantly reduced (P < 0.05). The white matter fibers of the entire brain in postischemic stroke patients are extensively damaged, and the topological properties of the structural brain network are altered, which are closely related to balance function. This study is helpful in further understanding the neural mechanism of balance function after ischemic stroke from the white matter fiber and structural brain network topological properties.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Encéfalo/diagnóstico por imagen , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen
11.
J Mol Cell Cardiol ; 186: 57-70, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37984156

RESUMEN

BACKGROUND: Macrophage-derived foam cells are a hallmark of atherosclerosis. Scavenger receptors, including lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (OLR-1), are the principal receptors responsible for the uptake and modification of LDL, facilitating macrophage lipid load and the uptake of oxidized LDL by arterial wall cells. Krüppel-like factor 15 (KLF15) is a transcription factor that regulates the expression of genes by binding to the promoter during transcription. Therefore, this study aimed to investigate the precise role of macrophage KLF15 in atherogenesis. METHODS: We used two murine models of atherosclerosis: mice injected with an adeno-associated virus (AAV) encoding the Asp374-to-Tyr mutant version of human PCSK9, followed by 12 weeks on a high-fat diet (HFD), and ApoE-/-- mice on a HFD. We subsequently injected mice with AAV-KLF15 and AAV-LacZ to assess the role of KLF15 in the development of atherosclerosis in vivo. Oil Red O, H&E, and Masson's trichome staining were used to evaluate atherosclerotic lesions. Western blots and RT-qPCR were used to assess protein and mRNA levels, respectively. RESULTS: We determined that KLF15 expression was downregulated during atherosclerosis formation, and KLF15 overexpression prevented atherosclerosis progression. KLF15 expression levels did not affect body weight or serum lipid levels in mice. However, KLF15 overexpression in macrophages prevented foam cell formation by reducing OLR-1-meditated lipid uptake. KLF15 directly targeted and transcriptionally downregulated OLR-1 levels. Restoration of OLR-1 reversed the beneficial effects of KLF15 in atherosclerosis. CONCLUSION: Macrophage KLF15 transcriptionally downregulated OLR-1 expression to reduce lipid uptake, thereby preventing foam cell formation and atherosclerosis. Thus, our results suggest that KLF15 is a potential therapeutic target for atherosclerosis.


Asunto(s)
Aterosclerosis , Células Espumosas , Humanos , Ratones , Animales , Células Espumosas/metabolismo , Proproteína Convertasa 9/metabolismo , Macrófagos/metabolismo , Aterosclerosis/patología , Lipoproteínas LDL/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo
12.
Plant Mol Biol ; 114(2): 20, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363403

RESUMEN

SQUAMOSA PROMOTER BINDING PROTEIN-LIKEs (SPLs) encode plant-specific transcription factors that regulate plant growth and development, stress response, and metabolite accumulation. However, there is limited information on Scutellaria baicalensis SPLs. In this study, 14 SbSPLs were identified and divided into 8 groups based on phylogenetic relationships. SbSPLs in the same group had similar structures. Abscisic acid-responsive (ABRE) and MYB binding site (MBS) cis-acting elements were found in the promoters of 8 and 6 SbSPLs. Segmental duplications and transposable duplications were the main causes of SbSPL expansion. Expression analysis based on transcriptional profiling showed that SbSPL1, SbSPL10, and SbSPL13 were highly expressed in roots, stems, and flowers, respectively. Expression analysis based on quantitative real-time polymerase chain reaction (RT‒qPCR) showed that most SbSPLs responded to low temperature, drought, abscisic acid (ABA) and salicylic acid (SA), among which the expression levels of SbSPL7/9/10/12 were significantly upregulated in response to abiotic stress. These results indicate that SbSPLs are involved in the growth, development and stress response of S. baicalensis. In addition, 8 Sba-miR156/157 s were identified, and SbSPL1-5 was a potential target of Sba-miR156/157 s. The results of target gene prediction and coexpression analysis together indicated that SbSPLs may be involved in the regulation of L-phenylalanine (L-Phe), lignin and jasmonic acid (JA) biosynthesis. In summary, the identification and characterization of the SbSPL gene family lays the foundation for functional research and provides a reference for improved breeding of S. baicalensis stress resistance and quality traits.


Asunto(s)
Ácido Abscísico , Scutellaria baicalensis , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Scutellaria baicalensis/genética , Scutellaria baicalensis/metabolismo , Filogenia , Fitomejoramiento , Estrés Fisiológico/genética , Hormonas/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/metabolismo
13.
J Am Chem Soc ; 146(2): 1305-1317, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38169369

RESUMEN

Aprotic lithium-oxygen (Li-O2) batteries are considered to be a promising alternative option to lithium-ion batteries for high gravimetric energy storage devices. However, the sluggish electrochemical kinetics, the passivation, and the structural damage to the cathode caused by the solid discharge products have greatly hindered the practical application of Li-O2 batteries. Herein, the nonsolid-state discharge products of the off-stoichiometric Li1-xO2 in the electrolyte solutions are achieved by iridium (Ir) single-atom-based porous organic polymers (termed as Ir/AP-POP) as a homogeneous, soluble electrocatalyst for Li-O2 batteries. In particular, the numerous atomic active sites act as the main nucleation sites of O2-related discharge reactions, which are favorable to interacting with O2-/LiO2 intermediates in the electrolyte solutions, owing to the highly similar lattice-matching effect between the in situ-formed Ir3Li and LiO2, achieving a nonsolid LiO2 as the final discharge product in the electrolyte solutions for Li-O2 batteries. Consequently, the Li-O2 battery with a soluble Ir/AP-POP electrocatalyst exhibits an ultrahigh discharge capacity of 12.8 mAh, an ultralow overpotential of 0.03 V, and a long cyclic life of 700 h with the carbon cloth cathode. The manipulation of nonsolid discharge products in aprotic Li-O2 batteries breaks the traditional growth mode of Li2O2, bringing Li-O2 batteries closer to being a viable technology.

14.
Int J Cancer ; 154(12): 2151-2161, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38429627

RESUMEN

Lung cancer is the first leading cause of cancer-related death in the United States, with lung adenocarcinoma as the major subtype accounting for 40% of all cases. To improve patient survival, image-based prognostic models were developed due to the ready availability of pathological images at diagnosis. However, the application of these models is hampered by two main challenges: the lack of publicly available image datasets with high-quality survival information and the poor interpretability of conventional convolutional neural network models. Here, we integrated matched transcriptomic and H&E staining data from TCGA (The Cancer Genome Atlas) to develop an image-based prognostic model, termed Deep-learning based Cell Graph (DeepCG) model. Instead of survival data, we used a gene signature to predict patient prognostic risks, which was then used as labels for training DeepCG. Importantly, by employing graph structures to capture cell patterns, DeepCG can provide cell-level interpretation, which was more biologically relevant than previous region-level insights. We validated the prognostic values of DeepCG in independent datasets and demonstrated its ability to identify prognostically informative cells in images.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Modelos de Riesgos Proporcionales , Adenocarcinoma del Pulmón/patología , Neoplasias Pulmonares/patología , Pronóstico , Perfilación de la Expresión Génica
15.
Biochem Cell Biol ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38917487

RESUMEN

In atherosclerosis, DNA methylation plays a key regulatory role in the expression of related genes. However, the molecular mechaism of these processes in HUVECs are unclear. Here, using high-throughput sequencing from the Infinium HumanMethylation450 assay, we manifested that the cg19564375 methylation of miR-520e promoter region in the peripheral blood of acute coronary syndrome (ACS) patients was higher than that of healthy controls. As shown by RQ-MSP, the upstream DNA methylation level of the miR-520e promoter region was considerably increased in ACS patients. miR-520e was markedly down-regulated in ACS patients compared with healthy controls. In the ox-LDL-induced HUVECs injury model, DNA methylation of the upstream region of miR-520e was significantly increased. With increasing concentrations of the methylase inhibitor 5-Aza, miR-520e expression was upregulated. The silence of methyltransferase DNMT1, rather than DNMT3a or DNMT3b, abolished the influence of miR-520e expression by ox-LDL treatment in HUVECs. A dual luciferase reporter assay revealed that miR-520e regulated the TGFBR2 3'-UTR region. After silencing TGFBR2, the promoting effect of miR-520e inhibitor on cell proliferation and migration may be attenuated. In conclusion, the expression of miR-520e is modified by its promoter region DNA methylation, and miR520e and its promoter region DNA methylation may be potential biomarkers in atherosclerosis.

16.
Oncologist ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38478404

RESUMEN

BACKGROUND: This study aimed to compare the survival outcomes of patients with initially unresectable hepatocellular carcinoma (HCC) and portal vein tumor thrombus (PVTT) who underwent or did not undergo salvage surgery followed by a triple combination conversion treatment consisted of locoregional treatment (LRT), tyrosine kinase inhibitors (TKIs), and anti-PD-1 antibodies. METHODS: The data from 93 consecutive patients with initially unresectable HCC and PVTT across 4 medical centers were retrospectively reviewed. They were converted successfully by the triple combination treatment and underwent or did not undergo salvage resection. The baseline characteristics, conversion schemes, conversion treatment-related adverse events (CTRAEs), overall survival (OS), and progression-free survival (PFS) of the salvage surgery and non-surgery groups were compared. Multivariate Cox regression analysis was performed to identify independent risk factors for OS and PFS. Additionally, subgroup survival analysis was conducted by stratification of degree of tumor response and type of PVTT. RESULTS: Of the 93 patients, 44 underwent salvage surgery, and 49 did not undergo salvage surgery. The OS and PFS of the salvage surgery and non-surgery groups were not significantly different (P = .370 and .334, respectively). The incidence and severity of CTRAEs of the 2 groups were also comparable. Subgroup analyses revealed that for patients with complete response (CR) or types III-IV PVTT, there was a trend toward better survival in patients who did not undergo salvage surgery. Multivariate analysis showed that baseline α-fetoprotein and best tumor response per mRECIST criteria were independent prognostic factors for OS and PFS. CONCLUSIONS: For patients with initially unresectable HCC and PVTT who were successfully converted by the triple combination therapy, salvage liver resection may not be necessary, especially for the patients with CR or types III-IV PVTT.

17.
Cancer Immunol Immunother ; 73(3): 55, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38366287

RESUMEN

BACKGROUND: For patients with unresectable locally advanced esophageal squamous cell carcinoma (ESCC), concurrent chemoradiotherapy (CCRT) is the current standard treatment; however, the prognosis remains poor. Immunotherapy combined with chemotherapy has demonstrated improved survival outcomes in advanced ESCC. Nevertheless, there is a lack of reports on the role of induction immunotherapy plus chemotherapy prior to CCRT for unresectable locally advanced ESCC. Therefore, this study aimed to evaluate the efficacy and safety of induction immunotherapy plus chemotherapy followed by definitive chemoradiotherapy in patients with unresectable locally advanced ESCC. METHODS: This study retrospectively collected clinical data of patients diagnosed with locally advanced ESCC who were treated with radical CCRT between 2017 and 2021 at our institution. The patients were divided into two groups: an induction immunotherapy plus chemotherapy group (induction IC group) or a CCRT group. To assess progression-free survival (PFS) and overall survival (OS), we employed the Kaplan-Meier method after conducting propensity score matching (PSM). RESULTS: A total of 132 patients with unresectable locally advanced ESCC were included in this study, with 61 (45.26%) patients in the induction IC group and 71 (54.74%) patients in the CCRT group. With a median follow-up of 37.0 months, median PFS and OS were 25.2 and 39.2 months, respectively. The patients in the induction IC group exhibited a significant improvement in PFS and OS in comparison with those in the CCRT group (median PFS: not reached [NR] versus 15.9 months, hazard ratio [HR] 0.526 [95%CI 0.325-0.851], P = 0.0077; median OS: NR versus 25.2 months, HR 0.412 [95%CI 0.236-0.719], P = 0.0012). After PSM (50 pairs), both PFS and OS remained superior in the induction IC group compared to the CCRT group (HR 0.490 [95%CI 0.280-0.858], P = 0.011; HR 0.454 [95%CI 0.246-0.837], P = 0.0093), with 2-year PFS rates of 67.6 and 42.0%, and the 2-year OS rates of 74.6 and 52.0%, respectively. Multivariate analysis revealed that lower tumor stage, concurrent chemotherapy using double agents, and induction immunotherapy plus chemotherapy before CCRT were associated with better prognosis. CONCLUSIONS: Our results showed for the first time that induction immunotherapy plus chemotherapy followed by CCRT for unresectable locally advanced ESCC provided a survival benefit with manageable safety profile. More prospective clinical studies should be warranted.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/terapia , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/patología , Estudios Retrospectivos , Estudios Prospectivos , Puntaje de Propensión , Quimioradioterapia/métodos , Inmunoterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
18.
Cancer Immunol Immunother ; 73(5): 85, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38554185

RESUMEN

TGF-ß1 and TGF-ßR1 play important roles in immune and inflammatory responses. Genetic variants of TGF-ß1 rs1800470 and TGF-ßR1 rs334348 have emerged as potentially prognostic biomarkers for HPV-related head and neck cancer, while their prognostic effect on survival of smoking-related head and neck cancer remains unknown. This study included 1403 patients with smoking-related head and neck cancer, and all these patients were genotyped for TGF-ß1 rs1800470 and TGF-ßR1 rs334348. Both univariate and multivariate analyses were performed to evaluate associations between the two functional genetic variants in microRNA binding sites of TGF-ß1 and TGF-ßR1 and survivals. Patients with TGF-ß1 rs1800470 CT or CC genotype had 30-35% risk reductions for OS, DSS, and DFS compared to patients with TT genotype among overall patients, ever smokers, and patients administered chemoradiation. Furthermore, patients with TGF-ßR1 rs334348 GA or GG genotype had significant 50-60% risk reductions for OS, DSS, and DFS compared to patients with AA genotype among overall patients and patients administered chemoradiation; among ever smokers, the risk reductions even reached 60-70%. The TCGA dataset was used for validation. These findings suggest that TGF-ß1 rs1800470 and TGF-ßR1 rs334348 significantly affect survival outcomes in patients with smoking-related head and neck cancer, especially in the subgroups of ever smokers and patients treated with chemoradiation. These genetic variants may serve as prognostic indicators for patients with smoking-related head and neck cancer and could play a role in advancing the field of personalized chemoradiation, thereby improving patient survival and quality of life.


Asunto(s)
Neoplasias de Cabeza y Cuello , MicroARNs , Humanos , MicroARNs/genética , Factor de Crecimiento Transformador beta1/genética , Calidad de Vida , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/terapia , Fumar/efectos adversos
19.
BMC Plant Biol ; 24(1): 458, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38797860

RESUMEN

BACKGROUND: The endosperm serves as the primary source of nutrients for maize (Zea mays L.) kernel embryo development and germination. Positioned at the base of the endosperm, the transfer cells (TCs) of the basal endosperm transfer layer (BETL) generate cell wall ingrowths, which enhance the connectivity between the maternal plant and the developing kernels. These TCs play a crucial role in nutrient transport and defense against pathogens. The molecular mechanism underlying BETL development in maize remains unraveled. RESULTS: This study demonstrated that the MYB-related transcription factor ZmMYBR29, exhibited specific expression in the basal cellularized endosperm, as evidenced by in situ hybridization analysis. Utilizing the CRISPR/Cas9 system, we successfully generated a loss-of-function homozygous zmmybr29 mutant, which presented with smaller kernel size. Observation of histological sections revealed abnormal development and disrupted morphology of the cell wall ingrowths in the BETL. The average grain filling rate decreased significantly by 26.7% in zmmybr29 mutant in comparison to the wild type, which impacted the dry matter accumulation within the kernels and ultimately led to a decrease in grain weight. Analysis of RNA-seq data revealed downregulated expression of genes associated with starch synthesis and carbohydrate metabolism in the mutant. Furthermore, transcriptomic profiling identified 23 genes that expressed specifically in BETL, and the majority of these genes exhibited altered expression patterns in zmmybr29 mutant. CONCLUSIONS: In summary, ZmMYBR29 encodes a MYB-related transcription factor that is expressed specifically in BETL, resulting in the downregulation of genes associated with kernel development. Furthermore, ZmMYBR29 influences kernels weight by affecting the grain filling rate, providing a new perspective for the complementation of the molecular regulatory network in maize endosperm development.


Asunto(s)
Grano Comestible , Endospermo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Factores de Transcripción , Zea mays , Zea mays/genética , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Grano Comestible/genética , Grano Comestible/crecimiento & desarrollo , Grano Comestible/metabolismo , Endospermo/genética , Endospermo/crecimiento & desarrollo , Endospermo/metabolismo , Pared Celular/metabolismo , Pared Celular/genética , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Sistemas CRISPR-Cas
20.
Am J Gastroenterol ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38775310

RESUMEN

INTRODUCTION: Concerns regarding bleeding remain in cold snare polypectomy (CSP) for small pedunculated (0-Ip) polyps. The aim of this study was to compare the risk of CSP and hot snare polypectomy (HSP) for such lesions. METHODS: Data on 0-Ip colorectal polyps ≤10 mm were extracted from a large, pragmatic, randomized trial. Immediate postpolypectomy bleeding (IPPB), defined as the perioperative use of a clip for bleeding, was evaluated through polyp-level analysis. Delayed postpolypectomy bleeding (DPPB), defined as bleeding occurring within 2 weeks postoperatively, was assessed at the patient-level among patients whose polyps were all ≤10 mm, including at least one 0-Ip polyp. RESULTS: A total of 647 0-Ip polyps (CSP: 306; HSP: 341) were included for IPPB analysis and 386 patients (CSP: 192; HSP: 194) for DPPB analysis. CSP was associated with a higher incidence of IPPB (10.8% vs 3.2%, P < 0.001) but no adverse clinical events. The procedure time of all polypectomies was shorter for CSP than for HSP (123.0 ± 117.8 vs 166.0 ± 237.7 seconds, P = 0.003), while the procedure time of polypectomies with IPPB were similar (249.8 ± 140.2 vs 227.4 ± 125.9 seconds, P = 0.64). DPPB was observed in 3 patients (1.5%) in the HSP group, including one patient (0.5%) with severe bleeding, but not in the CSP group. DISCUSSION: Despite CSP being associated with more IPPB events, it could be timely treated without adverse outcomes. Notably, no delayed bleeding occurred in the CSP group. Our findings support the use of CSP for 0-Ip polyps ≤ 10 mm.

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