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1.
Nature ; 615(7954): 913-919, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36922589

RESUMEN

Chromatin-binding proteins are critical regulators of cell state in haematopoiesis1,2. Acute leukaemias driven by rearrangement of the mixed lineage leukaemia 1 gene (KMT2Ar) or mutation of the nucleophosmin gene (NPM1) require the chromatin adapter protein menin, encoded by the MEN1 gene, to sustain aberrant leukaemogenic gene expression programs3-5. In a phase 1 first-in-human clinical trial, the menin inhibitor revumenib, which is designed to disrupt the menin-MLL1 interaction, induced clinical responses in patients with leukaemia with KMT2Ar or mutated NPM1 (ref. 6). Here we identified somatic mutations in MEN1 at the revumenib-menin interface in patients with acquired resistance to menin inhibition. Consistent with the genetic data in patients, inhibitor-menin interface mutations represent a conserved mechanism of therapeutic resistance in xenograft models and in an unbiased base-editor screen. These mutants attenuate drug-target binding by generating structural perturbations that impact small-molecule binding but not the interaction with the natural ligand MLL1, and prevent inhibitor-induced eviction of menin and MLL1 from chromatin. To our knowledge, this study is the first to demonstrate that a chromatin-targeting therapeutic drug exerts sufficient selection pressure in patients to drive the evolution of escape mutants that lead to sustained chromatin occupancy, suggesting a common mechanism of therapeutic resistance.


Asunto(s)
Resistencia a Antineoplásicos , Leucemia , Mutación , Proteínas Proto-Oncogénicas , Animales , Humanos , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Sitios de Unión/efectos de los fármacos , Sitios de Unión/genética , Cromatina/genética , Cromatina/metabolismo , Resistencia a Antineoplásicos/genética , Leucemia/tratamiento farmacológico , Leucemia/genética , Leucemia/metabolismo , Unión Proteica/efectos de los fármacos , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/química , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo
2.
Plant J ; 119(1): 137-152, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38569053

RESUMEN

Alternative splicing (AS) of pre-mRNAs increases the diversity of transcriptome and proteome and plays fundamental roles in plant development and stress responses. However, the prevalent changes in AS events and the regulating mechanisms of plants in response to pathogens remain largely unknown. Here, we show that AS changes are an important mechanism conferring cotton immunity to Verticillium dahliae (Vd). GauSR45a, encoding a serine/arginine-rich RNA binding protein, was upregulated expression and underwent AS in response to Vd infection in Gossypium australe, a wild diploid cotton species highly resistant to Vd. Silencing GauSR45a substantially reduced the splicing ratio of Vd-induced immune-associated genes, including GauBAK1 (BRI1-associated kinase 1) and GauCERK1 (chitin elicitor receptor kinase 1). GauSR45a binds to the GAAGA motif that is commonly found in the pre-mRNA of genes essential for PTI, ETI, and defense. The binding between GauSR45a and the GAAGA motif in the pre-mRNA of BAK1 was enhanced by two splicing factors of GauU2AF35B and GauU1-70 K, thereby facilitating exon splicing; silencing either AtU2AF35B or AtU1-70 K decreased the resistance to Vd in transgenic GauSR45a Arabidopsis. Overexpressing the short splicing variant of BAK1GauBAK1.1 resulted in enhanced Verticillium wilt resistance rather than the long one GauBAK1.2. Vd-induced far more AS events were in G. barbadense (resistant tetraploid cotton) than those in G. hirsutum (susceptible tetraploid cotton) during Vd infection, indicating resistance divergence in immune responses at a genome-wide scale. We provided evidence showing a fundamental mechanism by which GauSR45a enhances cotton resistance to Vd through global regulation of AS of immunity genes.


Asunto(s)
Empalme Alternativo , Ascomicetos , Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Gossypium , Enfermedades de las Plantas , Proteínas de Plantas , Gossypium/genética , Gossypium/microbiología , Gossypium/inmunología , Empalme Alternativo/genética , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ascomicetos/fisiología , Inmunidad de la Planta/genética , Verticillium
3.
Blood ; 139(25): 3630-3646, 2022 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-35421216

RESUMEN

Leukemic transformation (LT) of myeloproliferative neoplasm (MPN) has a dismal prognosis and is largely fatal. Mutational inactivation of TP53 is the most common somatic event in LT; however, the mechanisms by which TP53 mutations promote LT remain unresolved. Using an allelic series of mouse models of Jak2/Trp53 mutant MPN, we identify that only biallelic inactivation of Trp53 results in LT (to a pure erythroleukemia [PEL]). This PEL arises from the megakaryocyte-erythroid progenitor population. Importantly, the bone morphogenetic protein 2/SMAD pathway is aberrantly activated during LT and results in abnormal self-renewal of megakaryocyte-erythroid progenitors. Finally, we identify that Jak2/Trp53 mutant PEL is characterized by recurrent copy number alterations and DNA damage. Using a synthetic lethality strategy, by targeting active DNA repair pathways, we show that this PEL is highly sensitive to combination WEE1 and poly(ADP-ribose) polymerase inhibition. These observations yield new mechanistic insights into the process of p53 mutant LT and offer new, clinically translatable therapeutic approaches.


Asunto(s)
Trastornos Mieloproliferativos , Proteína p53 Supresora de Tumor , Animales , Proteína Morfogenética Ósea 2/genética , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Células Progenitoras de Megacariocitos y Eritrocitos/metabolismo , Megacariocitos/metabolismo , Ratones , Mutación , Trastornos Mieloproliferativos/genética , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
4.
J Exp Bot ; 75(1): 468-482, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37776224

RESUMEN

Sessile growing plants are always vulnerable to microbial pathogen attacks throughout their lives. To fend off pathogen invasion, plants have evolved a sophisticated innate immune system that consists of cell surface receptors and intracellular receptors. Somatic embryogenesis receptor kinases (SERKs) belong to a small group of leucine-rich repeat receptor-like kinases (LRR-RLKs) that function as co-receptors regulating diverse physiological processes. GENRAL REGULATORY FACTOR (GRF) proteins play an important role in physiological signalling transduction. However, the function of GRF proteins in plant innate immune signalling remains elusive. Here, we identified a GRF gene, GauGRF7, that is expressed both constitutively and in response to fungal pathogen infection. Intriguingly, silencing of GRF7 compromised plant innate immunity, resulting in susceptibility to Verticillium dahliae infection. Both transgenic GauGRF7 cotton and transgenic GauGRF7 Arabidopsis lines enhanced the innate immune response to V. dahliae infection, leading to high expression of two helper NLRs (hNLR) genes (ADR1 and NRG1) and pathogenesis-related genes, and increased ROS production and salicylic acid level. Moreover, GauGRF7 interacted with GhSERK1, which positively regulated GRF7-mediated innate immune response in cotton and Arabidopsis. Our findings revealed the molecular mechanism of the GRF protein in plant immune signaling and offer potential opportunities for improving plant resistance to V. dahliae infection.


Asunto(s)
Arabidopsis , Verticillium , Resistencia a la Enfermedad/genética , Verticillium/fisiología , Arabidopsis/metabolismo , Proteínas de Plantas/metabolismo , Transducción de Señal , Gossypium/genética , Gossypium/metabolismo , Enfermedades de las Plantas/microbiología , Regulación de la Expresión Génica de las Plantas
5.
Nature ; 623(7989): 920-921, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38012374
6.
J Appl Clin Med Phys ; 25(3): e14298, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38373294

RESUMEN

PURPOSE: Diagnosing Renal artery stenosis (RAS) presents challenges. This research aimed to develop a deep learning model for the computer-aided diagnosis of RAS, utilizing multimodal fusion technology based on ultrasound scanning images, spectral waveforms, and clinical information. METHODS: A total of 1485 patients received renal artery ultrasonography from Peking Union Medical College Hospital were included and their color doppler sonography (CDS) images were classified according to anatomical site and left-right orientation. The RAS diagnosis was modeled as a process involving feature extraction and multimodal fusion. Three deep learning (DL) models (ResNeSt, ResNet, and XCiT) were trained on a multimodal dataset consisted of CDS images, spectrum waveform images, and individual basic information. Predicted performance of different models were compared with senior physician and evaluated on a test dataset (N = 117 patients) with renal artery angiography results. RESULTS: Sample sizes of training and validation datasets were 3292 and 169 respectively. On test data (N = 676 samples), predicted accuracies of three DL models were more than 80% and the ResNeSt achieved the accuracy 83.49% ± 0.45%, precision 81.89% ± 3.00%, and recall 76.97% ± 3.7%. There was no significant difference between the accuracy of ResNeSt and ResNet (82.84% ± 1.52%), and the ResNeSt was higher than the XCiT (80.71% ± 2.23%, p < 0.05). Compared to the gold standard, renal artery angiography, the accuracy of ResNest model was 78.25% ± 1.62%, which was inferior to the senior physician (90.09%). Besides, compared to the multimodal fusion model, the performance of single-modal model on spectrum waveform images was relatively lower. CONCLUSION: The DL multimodal fusion model shows promising results in assisting RAS diagnosis.


Asunto(s)
Aprendizaje Profundo , Obstrucción de la Arteria Renal , Humanos , Obstrucción de la Arteria Renal/diagnóstico por imagen , Angiografía , Ultrasonografía Doppler en Color/métodos
7.
J Clin Ultrasound ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597807

RESUMEN

Venous ultrasound is the primary, widely accepted diagnostic tool to assess deep vein thrombosis (DVT) in the lower extremities. However, other focal lesions in the lower extremities can be identified on ultrasound. The sonographic appearance of these abnormalities may overlap the thrombosis, which included vascular tumors, Baker's cyst, hematoma, cancer thrombosis, and peripheral nerve tumors. This essay derives from cases diagnosed in our centers and published literature, with images available for illustrations, which may help to improve the clinical management of these findings.

8.
Molecules ; 29(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38930897

RESUMEN

This study investigated the mechanism by which fucoxanthin acts as a novel ferroptosis inducer to inhibit tongue cancer. The MTT assay was used to detect the inhibitory effects of fucoxanthin on SCC-25 human tongue squamous carcinoma cells. The levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), and total iron were measured. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blotting were used to assess glutathione peroxidase 4 (GPX4), nuclear factor erythroid 2-related factor 2 (Nrf2), Keap1, solute carrier family 7 member 11 (SLC7A11), transferrin receptor protein 1 (TFR1), p53, and heme oxygenase 1 (HO-1) expression. Molecular docking was performed to validate interactions. Compared with the control group, the activity of fucoxanthin-treated SCC-25 cells significantly decreased in a dose- and time-dependent manner. The levels of MMP, GSH, and SOD significantly decreased in fucoxanthin-treated SCC-25 cells; the levels of ROS, MDA, and total iron significantly increased. mRNA and protein expression levels of Keap1, GPX4, Nrf2, and HO-1 in fucoxanthin-treated cells were significantly decreased, whereas levels of TFR1 and p53 were significantly increased, in a concentration-dependent manner. Molecular docking analysis revealed that binding free energies of fucoxanthin with p53, SLC7A11, GPX4, Nrf2, Keap1, HO-1, and TFR1 were below -5 kcal/mol, primarily based on active site hydrogen bonding. Our findings suggest that fucoxanthin can induce ferroptosis in SCC-25 cells, highlighting its potential as a treatment for tongue cancer.


Asunto(s)
Ferroptosis , Hemo-Oxigenasa 1 , Simulación del Acoplamiento Molecular , Factor 2 Relacionado con NF-E2 , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Xantófilas , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Ferroptosis/efectos de los fármacos , Xantófilas/farmacología , Xantófilas/química , Hemo-Oxigenasa 1/metabolismo , Hemo-Oxigenasa 1/genética , Línea Celular Tumoral , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Neoplasias de la Lengua/tratamiento farmacológico , Neoplasias de la Lengua/metabolismo , Neoplasias de la Lengua/patología , Receptores de Transferrina/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Superóxido Dismutasa/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Antígenos CD
9.
Plant Biotechnol J ; 21(12): 2507-2524, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37553251

RESUMEN

Verticillium dahliae, one of the most destructive fungal pathogens of several crops, challenges the sustainability of cotton productivity worldwide because very few widely-cultivated Upland cotton varieties are resistant to Verticillium wilt (VW). Here, we report that REVEILLE2 (RVE2), the Myb-like transcription factor, confers the novel function in resistance to VW by regulating the jasmonic acid (JA) pathway in cotton. RVE2 expression was essentially required for the activation of JA-mediated disease-resistance response. RVE2 physically interacted with TPL/TPRs and disturbed JAZ proteins to recruit TPL and TPR1 in NINJA-dependent manner, which regulated JA response by relieving inhibited-MYC2 activity. The MYC2 then bound to RVE2 promoter for the activation of its transcription, forming feedback loop. Interestingly, a unique truncated RVE2 widely existing in D-subgenome (GhRVE2D) of natural Upland cotton represses the ability of the MYC2 to activate GhRVE2A promoter but not GausRVE2 or GbRVE2. The result could partially explain why Gossypium barbadense popularly shows higher resistance than Gossypium hirsutum. Furthermore, disturbing the JA-signalling pathway resulted into the loss of RVE2-mediated disease-resistance in various plants (Arabidopsis, tobacco and cotton). RVE2 overexpression significantly enhanced the resistance to VW. Collectively, we conclude that RVE2, a new regulatory factor, plays a pivotal role in fine-tuning JA-signalling, which would improve our understanding the mechanisms underlying the resistance to VW.


Asunto(s)
Verticillium , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Transducción de Señal/genética , Gossypium/metabolismo , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Regulación de la Expresión Génica de las Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
10.
Blood ; 137(10): 1377-1391, 2021 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-32871587

RESUMEN

Plasmacytoid dendritic cells (pDCs) are the principal natural type I interferon-producing dendritic cells. Neoplastic expansion of pDCs and pDC precursors leads to blastic plasmacytoid dendritic cell neoplasm (BPDCN), and clonal expansion of mature pDCs has been described in chronic myelomonocytic leukemia. The role of pDC expansion in acute myeloid leukemia (AML) is poorly studied. Here, we characterize patients with AML with pDC expansion (pDC-AML), which we observe in ∼5% of AML cases. pDC-AMLs often possess cross-lineage antigen expression and have adverse risk stratification with poor outcome. RUNX1 mutations are the most common somatic alterations in pDC-AML (>70%) and are much more common than in AML without pDC expansion and BPDCN. We demonstrate that pDCs are clonally related to, as well as originate from, leukemic blasts in pDC-AML. We further demonstrate that leukemic blasts from RUNX1-mutated AML upregulate a pDC transcriptional program, poising the cells toward pDC differentiation and expansion. Finally, tagraxofusp, a targeted therapy directed to CD123, reduces leukemic burden and eliminates pDCs in a patient-derived xenograft model. In conclusion, pDC-AML is characterized by a high frequency of RUNX1 mutations and increased expression of a pDC transcriptional program. CD123 targeting represents a potential treatment approach for pDC-AML.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Células Dendríticas/patología , Leucemia Mieloide Aguda/genética , Adulto , Anciano , Crisis Blástica/genética , Crisis Blástica/patología , Células Dendríticas/metabolismo , Femenino , Humanos , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Mutación
11.
Am J Hematol ; 98(1): 79-89, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36251406

RESUMEN

Measurable residual disease (MRD) is a powerful prognostic factor in acute myeloid leukemia (AML). However, pre-treatment molecular predictors of immunophenotypic MRD clearance remain unclear. We analyzed a dataset of 211 patients with pre-treatment next-generation sequencing who received induction chemotherapy and had MRD assessed by serial immunophenotypic monitoring after induction, subsequent therapy, and allogeneic stem cell transplant (allo-SCT). Induction chemotherapy led to MRD- remission, MRD+ remission, and persistent disease in 35%, 27%, and 38% of patients, respectively. With subsequent therapy, 34% of patients with MRD+ and 26% of patients with persistent disease converted to MRD-. Mutations in CEBPA, NRAS, KRAS, and NPM1 predicted high rates of MRD- remission, while mutations in TP53, SF3B1, ASXL1, and RUNX1 and karyotypic abnormalities including inv (3), monosomy 5 or 7 predicted low rates of MRD- remission. Patients with fewer individual clones were more likely to achieve MRD- remission. Among 132 patients who underwent allo-SCT, outcomes were favorable whether patients achieved early MRD- after induction or later MRD- after subsequent therapy prior to allo-SCT. As MRD conversion with chemotherapy prior to allo-SCT is rarely achieved in patients with specific baseline mutational patterns and high clone numbers, upfront inclusion of these patients into clinical trials should be considered.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda , Humanos , Pronóstico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Trasplante de Células Madre , Inducción de Remisión , Trasplante Homólogo , Neoplasia Residual/genética
12.
Analyst ; 148(3): 556-561, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36562478

RESUMEN

A novel method for detecting miRNA has been developed using a combination of duplex-specific nuclease signal amplification (DSNSA) and a catalytic hairpin assembly (CHA). In this work, a biotinylated trigger release (BTR) probe with a biotin group at the 3'-end and a CHA reaction sequence trigger as an initiator (catalyst I) at the 5'-end was designed to hybridize target miRNA. The DSN enzyme was introduced to initiate the DSNSA. The miRNA was released to consume more BTR probes and amplify the signals. Subsequently, streptavidin-coated magnetic beads (SA-MBs) were added to the DSNSA reaction solution to remove excess BTR probes that did not hybridize with miRNA, which would then separate BTR probes and catalyst-I, to ensure detection with high selectivity and sensitivity. The catalyst-I remaining in the solution could trigger the CHA reaction to enable signal amplification in the second step. The developed method exhibits a sensitive detection limit and excellent selectivity in identifying a high sequence homology among family members.


Asunto(s)
Técnicas Biosensibles , MicroARNs , Técnicas Biosensibles/métodos , MicroARNs/genética , Catálisis , Biotina , Estreptavidina , Endonucleasas , Límite de Detección
13.
Acta Pharmacol Sin ; 44(7): 1391-1403, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36697976

RESUMEN

The inflammatory responses involving infiltration and activation of liver macrophages play a vital role in acute liver failure (ALF). In the liver of ALF mice, cannabinoid receptor 2 (CB2R) is significantly upregulated on macrophages, while CB2R agonist GW405833 (GW) could protect against cell death in acute liver damage. In this study, we investigated the molecular mechanisms underlying the protective effects of GW against ALF in vivo and in vitro from a perspective of macrophage glycometabolism. Mice were pretreated with GW (10 mg/kg, i.p.), then were injected with D-GalN (750 mg/kg, i.p.) and LPS (10 mg/kg, i.p.) to induce ALF. We verified the protective effects of GW pretreatment in ALF mice. Furthermore, GW pretreatment significantly reduced liver macrophage infiltration and M1 polarization, and inhibited the release of inflammatory factors TNF-α and IL-1ß in ALF mice. These protective effects were eliminated by CB2R antagonist SR144528 or in CB2R-/- ALF mice. We used LPS-stimulated RAW264.7 cells as an in vitro M1 macrophage-centered model of inflammatory response, and demonstrated that pretreatment with GW (10 µM) significantly reduced glucose metabolism by inhibiting glycolysis, which inhibited LPS-induced macrophage proliferation and inflammatory cytokines release. We verified these results in a stable CB2R-/- RAW264.7 cell line. Moreover, we found that GW significantly inhibited the expression of hypoxia inducible factor 1α (HIF-1α). Using a stable HIF-1α-/- RAW264.7 cell line, we confirmed that GW reduced the release of inflammatory cytokines from macrophages and inhibited glycolysis by downregulating HIF-1α expression. In conclusion, activation of CB2Rs inhibits the proliferation of hepatic macrophages and release of inflammatory factors in ALF mice through downregulating HIF-1α to inhibit glycolysis.


Asunto(s)
Lipopolisacáridos , Fallo Hepático Agudo , Ratones , Animales , Lipopolisacáridos/farmacología , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/tratamiento farmacológico , Macrófagos , Citocinas/metabolismo , Proliferación Celular , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo
14.
Mol Cell ; 60(4): 561-70, 2015 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-26590715

RESUMEN

Chromatin regulatory mechanisms play a major role in the control of gene expression programs during normal development and are disrupted in specific disease states, particularly in cancer. Important mediators of chromatin regulatory processes can broadly be classified into writers, erasers, and readers of covalent chromatin modifications that modulate eukaryotic gene transcription and maintain the integrity of the genome. The reversibility and disease-specific nature of these chromatin states make these regulators attractive therapeutic targets. As such, there is an ever-increasing number of candidate therapies aimed at targeting cancer-associated chromatin states that are in various stages of preclinical and clinical development. In this review, we discuss recent advances that have been made in the rational therapeutic targeting of chromatin regulatory mechanisms and highlight certain cancers where there is a specific rationale to assess these therapeutic approaches.


Asunto(s)
Antineoplásicos/farmacología , Cromatina/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Ensayos Clínicos como Asunto , Epigénesis Genética/efectos de los fármacos , Humanos , Terapia Molecular Dirigida , Neoplasias/genética
15.
Angew Chem Int Ed Engl ; 62(27): e202303871, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37133306

RESUMEN

A novel type of covalent organic frameworks has been developed by assembling definite cobalt-nitrogen-carbon configurations onto carbon nanotubes using linkers that have varying electronic effects. This innovative approach has resulted in an efficient electrocatalyst for oxygen reduction, which is understood by a combination of in situ spectroelectrochemistry and the bond order theorem. The strong interaction between the electron-donating carbon nanotubes and the electron-accepting linker mitigates the trend of charge loss at cobalt sites, while inducing the generation of high spin state. This enhances the adsorption strength and electron transfer between the cobalt center and reactants/intermediates, leading to an improved oxygen reduction capability. This work not only presents an effective strategy for developing efficient non-noble metal electrocatalysts through reticular chemistry, but also provides valuable insights into regulating the electronic configuration and charge behavior of active sites in designing high-performance electrocatalysts.

16.
BMC Plant Biol ; 22(1): 443, 2022 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-36114469

RESUMEN

BACKGROUND: ATP-citrate lyase (ACL) plays a pivotal role in histone acetylation and aerobic glycolysis. In plant, ACL is a heteromeric enzyme composed of ACLA (45 kD) and ACLB (65 kD). So far, the function of ACL genes in cotton still remains unknown. RESULTS: Here, we identified three ACLA homologous sequences and two ACLB homologous in each genome/sub-genome of cotton species. Silencing ACLB in cotton led to cell death at newly-grown leaves and stem apexes. Simultaneously, in ACLB-silenced plants, transcription factors related to senescence including SGR, WRKY23 and Osl57 were observed to be activated. Further investigation showed that excessive H2O2 was accumulated, salicylic acid-dependent defense response and pathogenesis-related gene expressions were evidently enhanced in ACLB-silenced plants, implying that knockdown of ACLB genes leads to hypersensitive response-like cell death in cotton seedlings. However, as noted, serious cell death happened in newly-grown leaves and stem apexes in ACLB-silenced plants, which led to the failure of subsequent fungal pathogenicity assays. To confirm the role of ACLB gene in regulating plant immune response, the dicotyledonous model plant Arabidopsis was selected for functional verification of ACLB gene. Our results indicate the resistance to Verticillium dahliae infection in the Arabidopsis mutant aclb-2 were enhanced without causing strong cell death. Ectopic expression of GausACLB-2 in Arabidopsis weakened its resistance to V. dahliae either in Col-0 or in aclb-2 background, in which the expression level of ACLB is negatively correlated with the resistance to V. dahliae. CONCLUSIONS: These results indicate that ACLB has a new function in negatively affecting the induction of plant defense response and cell death in cotton, which provides theoretical guidance for developing cotton varieties with resistance against Verticillium wilt.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Verticillium , ATP Citrato (pro-S)-Liasa/metabolismo , Adenosina Trifosfato , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Muerte Celular , Histonas , Peróxido de Hidrógeno/metabolismo , Complejos Multienzimáticos , Oxo-Ácido-Liasas , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Ácido Salicílico/metabolismo , Factores de Transcripción/metabolismo , Verticillium/fisiología
17.
Pharmacol Res ; 177: 106101, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35104632

RESUMEN

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second leading cause of cancer-related deaths in the world. The downregulation of farnesoid X receptor (FXR) is frequently founded in CRC patients. The current study found that the decreased expression of FXR in colorectal cancer leads to disorders of bile acids (BAs) metabolism. The altered BAs profile shaped distinct intestinal flora and positively regulated secretory immunoglobulin A (sIgA). The dual regulation of BAs and sIgA enhanced adhesion and biofilm formation of enterotoxigenic Bacteroides fragilis (ETBF), which has a colorectal tumorigenesis effect. The abundance of ETBF increased significantly in intestinal mucosa of colitis-associated cancer (CAC) mice, and finally promoted the development of colorectal cancer. This study suggests that downregulation of FXR in CRC results in BAs dysregulation, and BAs have strong effects on sIgA and gut flora. The elevated BAs concentration and altered gut microbiome are risk factors for CRC.


Asunto(s)
Infecciones Bacterianas , Neoplasias Colorrectales , Animales , Bacteroides fragilis/metabolismo , Ácidos y Sales Biliares/metabolismo , Carcinogénesis , Transformación Celular Neoplásica , Regulación hacia Abajo , Humanos , Inmunoglobulina A Secretora/metabolismo , Ratones
18.
Analyst ; 147(22): 4986-4990, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36214814

RESUMEN

Polynucleotide kinase (PNK), a bifunctional enzyme with 5'-kinase and 3'-phosphatase activities, plays an important role in DNA repair and is associated with various diseases. Here, we developed a primer-free, sensitive, and isothermal quantitative assay to detect PNK activity. In the presence of PNK, the 3'-phosphate group of the substrate was digested with 3'-OH, initiating the amplification reaction. Elongated dsDNA binds to the dsDNA-specific fluorescent dye EvaGreen, leading to a significant enhancement in fluorescence intensity. The limit of detection (LOD) of this method was 7.7 × 10-7 U µL-1, which is comparable or even superior to that of previously reported methods. This approach also showed good quantitative ability in complex cell lysates, indicating potential for biological sample analysis. Additionally, this facile and sensitive assay can be used to screen for PNK inhibitors. The proposed method provides a promising platform for sensitive PNK activity monitoring and inhibition screening for drug discovery and clinical treatment.


Asunto(s)
Técnicas Biosensibles , Polinucleótido 5'-Hidroxil-Quinasa , Polinucleótido 5'-Hidroxil-Quinasa/análisis , Bacteriófago T4 , Espectrometría de Fluorescencia/métodos , Límite de Detección , Fosfatos , Técnicas Biosensibles/métodos
19.
Bioorg Med Chem ; 56: 116599, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35041998

RESUMEN

The aminobenzamide is selective to class I histone deacetylases (HDACs) and displays unique tight-binding/slow-off HDAC-binding mechanism. Herein, we report a series of 9-substituted purine aminobenzamides that selectively inhibit class I HDACs. The activities in vitro showed compound 9d exhibited 12 folds more potent than MS-275 against HDAC1 isoform and showed excellent inhibitory activity on cancer cells, including HCT-116, MDA-MB-231, K562 cell lines. The metabolic stability of 9d was much better than that of the well-known HDAC inhibitor SAHA. Pulse exposure test of western blot assay demonstrated that 9a, 9d induced histone acetylation in a similar manner to MS-275. Further biological validation demonstrated that 9d prevented cell transition from G1 phase to S phase by reducing Cyclin D1, CDK2 and lifting p21, induced early apoptosis by upregulating BAX and downregulating Bcl-2 in HCT-116 cells.


Asunto(s)
Antineoplásicos/farmacología , Benzamidas/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Purinas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Benzamidas/síntesis química , Benzamidas/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores de Histona Desacetilasas/síntesis química , Inhibidores de Histona Desacetilasas/química , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Purinas/química , Relación Estructura-Actividad
20.
BMC Womens Health ; 22(1): 556, 2022 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-36581918

RESUMEN

PURPOSE: To analyze the diagnostic value of placenta three-dimensional (3D) energy blood flow parameters combined with maternal serum AFP, ß-hCG, sFlt-1 and CK levels for PA. METHODS: 30 pregnant women with PA and 30 pregnant women with normal placenta were randomly selected in the Affiliated Maternal and Child Health Hospital of Nantong University from January 2021 to December 2021. Thereafter, the 3D energy ultrasound was applied to detect the placenta VI, FI and VFI. Moreover, the diagnostic value of different parameters combined with serum AFP, ß-hCG, sFlt-1 and CK levels for PA was analyzed. RESULTS: Multivariate analysis results indicated that, gravidity > 2 and with/without placenta previa were the independent risk factors for PA (P < 0.05). In PA group, the AFP, ß-hCG, CK, placenta VI, FI and VFI values were higher than those in non-PA group, while sFlt-1 was apparently lower than that in non-PA group. With the increase in PA degree, the serum AFP, ß-hCG and CK levels increased. Meanwhile, serum sFlt-1 level was negatively correlated with PA degree. Serum AFP, ß-hCG, sFlt-1, CK and placenta VFI showed prediction potency for PA, and their combined detection attained the optimal diagnostic value for predicting PA. ROC curve analysis suggested that, serum AFP, ß-hCG, sFlt-1, CK and 3D ultrasound VFI value had the greatest AUC values in predicting PA, which might provide reference for the clinical diagnosis and disease evaluation of PA. Conclusion Serum AFP, ß-hCG, sFlt-1, CK and placental VFI can increase the consistency in the diagnosis of PA. Serum markers combined with 3D ultrasound blood flow imaging can improve the sensitivity and specificity of prenatal diagnosis of PA, which provides an important reference for clinical diagnosis and treatment.


Asunto(s)
Placenta Accreta , Placenta , Niño , Embarazo , Humanos , Femenino , Placenta/irrigación sanguínea , Placenta/química , Placenta/diagnóstico por imagen , Placenta Accreta/diagnóstico por imagen , alfa-Fetoproteínas/análisis , Ultrasonografía , Diagnóstico Prenatal/métodos
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