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1.
Cell ; 186(13): 2865-2879.e20, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37301196

RESUMEN

Retroelements are the widespread jumping elements considered as major drivers for genome evolution, which can also be repurposed as gene-editing tools. Here, we determine the cryo-EM structures of eukaryotic R2 retrotransposon with ribosomal DNA target and regulatory RNAs. Combined with biochemical and sequencing analysis, we reveal two essential DNA regions, Drr and Dcr, required for recognition and cleavage. The association of 3' regulatory RNA with R2 protein accelerates the first-strand cleavage, blocks the second-strand cleavage, and initiates the reverse transcription starting from the 3'-tail. Removing 3' regulatory RNA by reverse transcription allows the association of 5' regulatory RNA and initiates the second-strand cleavage. Taken together, our work explains the DNA recognition and RNA supervised sequential retrotransposition mechanisms by R2 machinery, providing insights into the retrotransposon and application reprogramming.


Asunto(s)
ARN , Retroelementos , ARN/metabolismo , División del ADN , ADN Polimerasa Dirigida por ARN/metabolismo , Transcripción Reversa
2.
Cell ; 170(6): 1224-1233.e15, 2017 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-28844692

RESUMEN

CRISPR-Cas9 proteins function within bacterial immune systems to target and destroy invasive DNA and have been harnessed as a robust technology for genome editing. Small bacteriophage-encoded anti-CRISPR proteins (Acrs) can inactivate Cas9, providing an efficient off switch for Cas9-based applications. Here, we show that two Acrs, AcrIIC1 and AcrIIC3, inhibit Cas9 by distinct strategies. AcrIIC1 is a broad-spectrum Cas9 inhibitor that prevents DNA cutting by multiple divergent Cas9 orthologs through direct binding to the conserved HNH catalytic domain of Cas9. A crystal structure of an AcrIIC1-Cas9 HNH domain complex shows how AcrIIC1 traps Cas9 in a DNA-bound but catalytically inactive state. By contrast, AcrIIC3 blocks activity of a single Cas9 ortholog and induces Cas9 dimerization while preventing binding to the target DNA. These two orthogonal mechanisms allow for separate control of Cas9 target binding and cleavage and suggest applications to allow DNA binding while preventing DNA cutting by Cas9.


Asunto(s)
Sistemas CRISPR-Cas , Endonucleasas/antagonistas & inhibidores , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Bacteriófagos/genética , Bacteriófagos/metabolismo , Endonucleasas/química , Endonucleasas/genética , Endonucleasas/metabolismo , Evolución Molecular , Células HEK293 , Humanos , Dominios Proteicos , Alineación de Secuencia
3.
Nature ; 630(8016): 484-492, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38811729

RESUMEN

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacterium species contains a novel ß-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR-Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9-PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and 'growth evolutionary' trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs-such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.


Asunto(s)
Bacterias , Bacteriófagos , Proteína 9 Asociada a CRISPR , Sistemas CRISPR-Cas , Bacterias/virología , Bacterias/genética , Bacterias/inmunología , Bacteriófagos/genética , Bacteriófagos/inmunología , Chryseobacterium/genética , Chryseobacterium/inmunología , Chryseobacterium/virología , Proteína 9 Asociada a CRISPR/química , Proteína 9 Asociada a CRISPR/genética , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/inmunología , División del ADN , Sitios Genéticos/genética , Modelos Moleculares , Dominios Proteicos
4.
Mol Cell ; 82(6): 1199-1209.e6, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35219382

RESUMEN

A compact protein with a size of <1,000 amino acids, the CRISPR-associated protein CasX is a fundamentally distinct RNA-guided nuclease when compared to Cas9 and Cas12a. Although it can induce RNA-guided genome editing in mammalian cells, the activity of CasX is less robust than that of the widely used S. pyogenes Cas9. Here, we show that structural features of two CasX homologs and their guide RNAs affect the R-loop complex assembly and DNA cleavage activity. Cryo-EM-based structural engineering of either the CasX protein or the guide RNA produced two new CasX genome editors (DpbCasX-R3-v2 and PlmCasX-R1-v2) with significantly improved DNA manipulation efficacy. These results advance both the mechanistic understanding of CasX and its application as a genome-editing tool.


Asunto(s)
Edición Génica , ARN Guía de Kinetoplastida , Animales , Sistemas CRISPR-Cas/genética , Endonucleasas/genética , Endonucleasas/metabolismo , Edición Génica/métodos , Mamíferos/metabolismo , ARN/genética , ARN Guía de Kinetoplastida/genética , ARN Guía de Kinetoplastida/metabolismo
5.
Mol Cell ; 73(3): 601-610.e5, 2019 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-30595438

RESUMEN

CRISPR-Cas immune systems utilize RNA-guided nucleases to protect bacteria from bacteriophage infection. Bacteriophages have in turn evolved inhibitory "anti-CRISPR" (Acr) proteins, including six inhibitors (AcrIIA1-AcrIIA6) that can block DNA cutting and genome editing by type II-A CRISPR-Cas9 enzymes. We show here that AcrIIA2 and its more potent homolog, AcrIIA2b, prevent Cas9 binding to DNA by occluding protein residues required for DNA binding. Cryo-EM-determined structures of AcrIIA2 or AcrIIA2b bound to S. pyogenes Cas9 reveal a mode of competitive inhibition of DNA binding that is distinct from other known Acrs. Differences in the temperature dependence of Cas9 inhibition by AcrIIA2 and AcrIIA2b arise from differences in both inhibitor structure and the local inhibitor-binding environment on Cas9. These findings expand the natural toolbox for regulating CRISPR-Cas9 genome editing temporally, spatially, and conditionally.


Asunto(s)
Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas , ADN/metabolismo , Edición Génica/métodos , Fagos Pseudomonas/metabolismo , Pseudomonas aeruginosa/enzimología , ARN Guía de Kinetoplastida/metabolismo , Temperatura , Proteínas Virales/metabolismo , Unión Competitiva , Proteína 9 Asociada a CRISPR/antagonistas & inhibidores , Proteína 9 Asociada a CRISPR/genética , Proteína 9 Asociada a CRISPR/ultraestructura , Microscopía por Crioelectrón , ADN/genética , ADN/ultraestructura , Escherichia coli/enzimología , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica , Modelos Moleculares , Conformación de Ácido Nucleico , Unión Proteica , Conformación Proteica , Fagos Pseudomonas/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/virología , ARN Guía de Kinetoplastida/genética , ARN Guía de Kinetoplastida/ultraestructura , Relación Estructura-Actividad , Proteínas Virales/genética , Proteínas Virales/ultraestructura
6.
Nucleic Acids Res ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38994558

RESUMEN

CasX (also known as Cas12e), a Class 2 CRISPR-Cas system, shows promise in genome editing due to its smaller size compared to the widely used Cas9 and Cas12a. Although the structures of CasX-sgRNA-DNA ternary complexes have been resolved and uncover a distinctive NTSB domain, the dynamic behaviors of CasX are not well characterized. In this study, we employed single-molecule and biochemical assays to investigate the conformational dynamics of two CasX homologs, DpbCasX and PlmCasX, from DNA binding to target cleavage and fragment release. Our results indicate that CasX cleaves the non-target strand and the target strand sequentially with relative irreversible dynamics. The two CasX homologs exhibited different cleavage patterns and specificities. The dynamic characterization of CasX also reveals a PAM-proximal seed region, providing guidance for CasX-based effector design. Further studies elucidate the mechanistic basis for why modification of sgRNA and the NTSB domain can affect its activity. Interestingly, CasX has less effective target search efficiency than Cas9 and Cas12a, potentially accounting for its lower genome editing efficiency. This observation opens a new avenue for future protein engineering.

7.
FASEB J ; 38(13): e23781, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38941212

RESUMEN

Reactive astrocytes are important pathophysiologically and synthesize neurosteroids. We observed that LPS increased immunoreactive TLR4 and key steroidogenic enzymes in cortical astrocytes of rats and investigated whether corticosteroids are produced and mediate astrocytic TLR4-dependent innate immune responses. We found that LPS increased steroidogenic acute regulatory protein (StAR) and StAR-dependent aldosterone production in purified astrocytes. Both increases were blocked by the TLR4 antagonist TAK242. LPS also increased 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) and corticosterone production, and both were prevented by TAK242 and by siRNAs against 11ß-HSD1, StAR, or aldosterone synthase (CYP11B2). Knockdown of 11ß-HSD1, StAR, or CYP11B2 or blocking either mineralocorticoid receptors (MR) or glucocorticoid receptors (GR) prevented dephosphorylation of p-Ser9GSK-3ß, activation of NF-κB, and the GSK-3ß-dependent increases of C3, IL-1ß, and TNF-α caused by LPS. Exogenous aldosterone mimicked the MR- and GSK-3ß-dependent pro-inflammatory effects of LPS in astrocytes, but corticosterone did not. Supernatants from astrocytes treated with LPS reduced MAP2 and viability of cultured neurons except when astrocytic StAR or MR was inhibited. In adrenalectomized rats, intracerebroventricular injection of LPS increased astrocytic TLR4, StAR, CYP11B2, and 11ß-HSD1, NF-κB, C3 and IL-1ß, decreased astrocytic p-Ser9GSK-3ß in the cortex and was neurotoxic, except when spironolactone was co-injected, consistent with the in vitro results. LPS also activated NF-κB in some NeuN+ and CD11b+ cells in the cortex, and these effects were prevented by spironolactone. We conclude that intracrine aldosterone may be involved in the TLR4-dependent innate immune responses of astrocytes and can trigger paracrine effects by activating astrocytic MR/GSK-3ß/NF-κB signaling.


Asunto(s)
Astrocitos , Glucógeno Sintasa Quinasa 3 beta , Inmunidad Innata , Lipopolisacáridos , Receptor Toll-Like 4 , Animales , Astrocitos/metabolismo , Astrocitos/efectos de los fármacos , Receptor Toll-Like 4/metabolismo , Inmunidad Innata/efectos de los fármacos , Ratas , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Lipopolisacáridos/farmacología , Corticoesteroides/farmacología , Ratas Sprague-Dawley , Células Cultivadas , Receptores de Mineralocorticoides/metabolismo , Aldosterona/metabolismo , Aldosterona/farmacología , Masculino , FN-kappa B/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Corticosterona/farmacología
8.
Nature ; 568(7752): E8-E10, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30944483

RESUMEN

In this Article, owing to issues with the first 30 nucleotides of the sgRNA, which run in the opposite direction, corrections have been made to the Protein Data Bank (PDB) accessions in the 'Data availability' section, and this also affects Figs. 3, 4, Extended Data Fig. 6, Supplementary Table 1 and Supplementary Video 1. The original Article has been corrected online. See the accompanying Amendment for further details.

9.
Nature ; 566(7743): 218-223, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30718774

RESUMEN

The RNA-guided CRISPR-associated (Cas) proteins Cas9 and Cas12a provide adaptive immunity against invading nucleic acids, and function as powerful tools for genome editing in a wide range of organisms. Here we reveal the underlying mechanisms of a third, fundamentally distinct RNA-guided genome-editing platform named CRISPR-CasX, which uses unique structures for programmable double-stranded DNA binding and cleavage. Biochemical and in vivo data demonstrate that CasX is active for Escherichia coli and human genome modification. Eight cryo-electron microscopy structures of CasX in different states of assembly with its guide RNA and double-stranded DNA substrates reveal an extensive RNA scaffold and a domain required for DNA unwinding. These data demonstrate how CasX activity arose through convergent evolution to establish an enzyme family that is functionally separate from both Cas9 and Cas12a.


Asunto(s)
Proteínas Asociadas a CRISPR/clasificación , Proteínas Asociadas a CRISPR/ultraestructura , Sistemas CRISPR-Cas/genética , Edición Génica , Proteínas Asociadas a CRISPR/química , Proteínas Asociadas a CRISPR/metabolismo , Microscopía por Crioelectrón , ADN/química , ADN/metabolismo , ADN/ultraestructura , División del ADN , Escherichia coli/genética , Evolución Molecular , Silenciador del Gen , Genoma Bacteriano/genética , Genoma Humano/genética , Humanos , Modelos Moleculares , Conformación de Ácido Nucleico , Dominios Proteicos , ARN Guía de Kinetoplastida/metabolismo
10.
Nano Lett ; 24(20): 6192-6200, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38666542

RESUMEN

Creating artificial synapses that can interact with biological neural systems is critical for developing advanced intelligent systems. However, there are still many difficulties, including device morphology and fluid selection. Based on Micro-Electro-Mechanical System technologies, we utilized two immiscible electrolytes to form a liquid/liquid interface at the tip of a funnel nanochannel, effectively enabling a wafer-level fabrication, interactions between multiple information carriers, and electron-to-chemical signal transitions. The distinctive ionic transport properties successfully achieved a hysteresis in ionic transport, resulting in adjustable multistage conductance gradient and synaptic functions. Notably, the device is similar to biological systems in terms of structure and signal carriers, especially for the low operating voltage (200 mV), which matches the biological neural potential (∼110 mV). This work lays the foundation for realizing the function of iontronics neuromorphic computing at ultralow operating voltages and in-memory computing, which can break the limits of information barriers for brain-machine interfaces.


Asunto(s)
Nanotecnología , Sinapsis , Sinapsis/fisiología , Nanotecnología/instrumentación , Electrólitos/química , Nanoestructuras/química , Neuronas/fisiología , Conductividad Eléctrica
11.
Biophys J ; 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38414236

RESUMEN

In recent years, advancements in retinal image analysis, driven by machine learning and deep learning techniques, have enhanced disease detection and diagnosis through automated feature extraction. However, challenges persist, including limited data set diversity due to privacy concerns and imbalanced sample pairs, hindering effective model training. To address these issues, we introduce the vessel and style guided generative adversarial network (VSG-GAN), an innovative algorithm building upon the foundational concept of GAN. In VSG-GAN, a generator and discriminator engage in an adversarial process to produce realistic retinal images. Our approach decouples retinal image generation into distinct modules: the vascular skeleton and background style. Leveraging style transformation and GAN inversion, our proposed hierarchical variational autoencoder module generates retinal images with diverse morphological traits. In addition, the spatially adaptive denormalization module ensures consistency between input and generated images. We evaluate our model on MESSIDOR and RITE data sets using various metrics, including structural similarity index measure, inception score, Fréchet inception distance, and kernel inception distance. Our results demonstrate the superiority of VSG-GAN, outperforming existing methods across all evaluation assessments. This underscores its effectiveness in addressing data set limitations and imbalances. Our algorithm provides a novel solution to challenges in retinal image analysis by offering diverse and realistic retinal image generation. Implementing the VSG-GAN augmentation approach on downstream diabetic retinopathy classification tasks has shown enhanced disease diagnosis accuracy, further advancing the utility of machine learning in this domain.

12.
J Am Chem Soc ; 146(23): 15977-15985, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38713009

RESUMEN

Unveiling innovative mechanisms to design new highly efficient fluorescent materials and, thereby, fabricate high-performance organic light-emitting diodes (OLEDs) is a concerted endeavor in both academic and industrial circles. Polycyclic aromatic hydrocarbons (PAHs) have been widely used as fluorescent emitters in blue OLEDs, but device performances are far from satisfactory. In response, we propose the concept of "nitrogen effects" endowed by doping electron-withdrawing nitrogen atoms into PAH fluorescence emitters. The presence of the n orbital on the imine nitrogen is conducive to promoting electron coupling, which leads to increased molar absorptivity and an accelerated radiative decay rate of emitters, thereby facilitating the Förster energy transfer (FET) process in the OLEDs. Additionally, electronically withdrawing nitrogen atoms enhances host-guest interactions, thereby positively affecting the FET process and the horizontal orientation factor of the emitting layer. To validate the "nitrogen effects" concept, cobalt-catalyzed multiple C-H annulation has been utilized to incorporate alkynes into the imine-based frameworks, which enables various imine-embedded PAH (IE-PAH) fluorescence emitters. The cyclization demonstrates notable regioselectivity, thereby offering a practical tool to precisely introduce peripheral groups at desired positions with bulky alkyl units positioned adjacent to the nitrogen atoms, which were previously beyond reach through the Friedel-Crafts reaction. Blue OLEDs fabricated with IE-PAHs exhibit outstanding performance with a maximum external quantum efficiency (EQEmax) of 32.7%. This achievement sets a groundbreaking record for conventional blue PAH-based fluorescent emitters, which have an EQEmax of 24.0%.

13.
J Am Chem Soc ; 146(9): 6240-6251, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38315826

RESUMEN

The inherent benefits of C-H activation have given rise to innovative approaches in designing organic optoelectronic molecules that depart from conventional methods. While theoretical calculations have suggested the suitability of the 2,6-naphthyridine scaffold for electron transport materials (ETMs) in organic light-emitting diodes (OLEDs), the existing synthetic methodologies have proven to be insufficient for the construction of multiple arylated and fully aryl-substituted molecules. Herein, we present a solution for the synthesis of 2,6-naphthyridine derivatives, with the rhodium-catalyzed consecutive C-H activation-annulation process of fumaric acid with alkynes standing as the pivotal step within this strategy. The ETMs, purposefully designed and synthesized based on the 2,6-naphthyridine framework, exhibit an impressively high glass-transition temperature (Tg) of 282 °C and high electron mobility (µe), setting a new benchmark for ETMs in OLEDs with a µe exceeding 10-2 cm2 V-1 s-1. These materials prove to be versatile ETM candidates suitable for red, green, and blue phosphorescent OLED devices.

14.
Small ; 20(22): e2306994, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38098339

RESUMEN

The performances of solid-state polymer electrolytes are urgently required to be further improved for high energy density lithium metal batteries. Herein, a highly reinforced ultrathin composite polymer electrolyte (PLPP) is successfully fabricated in a large scale by densely filling the well-dispersed mixture of polyethylene oxide (PEO), Li-salt (LiTFSI) and a polymer of intrinsic microporosity (PIM-1) into porous poly(tetrafluoroethylene) (PTFE) matrix. Based on the macro-plus-micro synergistic enhancement of the PTFE with excellent mechanical properties and the soluble PIM-1 with suitable functional groups, the PLPP electrolyte exhibits excellent properties including mechanical stress, thermal stability, lithium-ion transference number, voltage window and ionic conductivity, which are all superior to the typical PEO/LiTFSI electrolytes. As a result, the Li/PLPP/Li symmetric cell can stably cycle for > 2000 h, and the LiFePO4/PLPP/Li full cell exhibits excellent rate performance (>10 C) and high cycling stability with an initial capacity of 158.8 mAh g-1 and a capacity retention of 78.8% after 300 cycles. In addition, the excellent mechanical properties as well as the wide voltage window reasonably result in the stable operation of full cells with either high-loading cathode up to 28.1 mg cm-2 or high voltage cathode with high energy density.

15.
Brief Bioinform ; 23(1)2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-34864886

RESUMEN

Gene expression is directly controlled by transcription factors (TFs) in a complex combination manner. It remains a challenging task to systematically infer how the cooperative binding of TFs drives gene activity. Here, we quantitatively analyzed the correlation between TFs and surveyed the TF interaction networks associated with gene expression in GM12878 and K562 cell lines. We identified six TF modules associated with gene expression in each cell line. Furthermore, according to the enrichment characteristics of TFs in these TF modules around a target gene, a convolutional neural network model, called TFCNN, was constructed to identify gene expression level. Results showed that the TFCNN model achieved a good prediction performance for gene expression. The average of the area under receiver operating characteristics curve (AUC) can reach up to 0.975 and 0.976, respectively in GM12878 and K562 cell lines. By comparison, we found that the TFCNN model outperformed the prediction models based on SVM and LDA. This is due to the TFCNN model could better extract the combinatorial interaction among TFs. Further analysis indicated that the abundant binding of regulatory TFs dominates expression of target genes, while the cooperative interaction between TFs has a subtle regulatory effects. And gene expression could be regulated by different TF combinations in a nonlinear way. These results are helpful for deciphering the mechanism of TF combination regulating gene expression.


Asunto(s)
Aprendizaje Profundo , Factores de Transcripción , Expresión Génica , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
16.
Appl Environ Microbiol ; 90(4): e0235523, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38535171

RESUMEN

Halophyte-based remediation emerges as a novel strategy for ameliorating saline soils, offering a sustainable alternative to conventional leaching methods. While bioremediation is recognized for its ability to energize soil fertility and structure, the complex interplays among plant traits, soil functions, and soil microbial diversity remain greatly unknown. Here, we conducted a 5-year field experiment involving the continuous cultivation of the annual halophyte Suaeda salsa in saline soils to explore soil microbial diversity and their relationships with plant traits and soil functions. Our findings demonstrate that a decline in soil salinity corresponded with increases in the biomass and seed yield of S. salsa, which sustained a consistent seed oil content of approximately 22% across various salinity levels. Significantly, prolonged cultivation of halophytes substantially augmented soil microbial diversity, particularly from the third year of cultivation. Moreover, we identified positive associations between soil multifunctionality, seed yield, and taxonomic richness within a pivotal microbial network module. Soils enriched with taxa from this module showed enhanced multifunctionality and greater seed yields, correlating with the presence of functional genes implicated in nitrogen fixation and nitrification. Genomic analysis suggests that these taxa have elevated gene copy numbers of crucial functional genes related to nutrient cycling. Overall, our study emphasizes that the continuous cultivation of S. salsa enhances soil microbial diversity and recovers soil multifunctionality, expanding the understanding of plant-soil-microbe feedback in bioremediation.IMPORTANCEThe restoration of saline soils utilizing euhalophytes offers a viable alternative to conventional irrigation techniques for salt abatement and soil quality enhancement. The ongoing cultivation of the annual Suaeda salsa and its associated plant traits, soil microbial diversity, and functionalities are, however, largely underexplored. Our investigation sheds light on these dynamics, revealing that cultivation of S. salsa sustains robust plant productivity while fostering soil microbial diversity and multifunctionality. Notably, the links between enhanced soil multifunctionality, increased seed yield, and network-dependent taxa were found, emphasizing the importance of key microbial taxa linked with functional genes vital to nitrogen fixation and nitrification. These findings introduce a novel understanding of the role of soil microbes in bioremediation and advance our knowledge of the ecological processes that are vital for the rehabilitation of saline environments.


Asunto(s)
Chenopodiaceae , Suelo , Suelo/química , Solución Salina , Cloruro de Sodio , Nitrificación , Plantas Tolerantes a la Sal
17.
BMC Cancer ; 24(1): 139, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287300

RESUMEN

BACKGROUND: Identifying lymph node metastasis areas during surgery for early invasive lung adenocarcinoma remains challenging. The aim of this study was to develop a nomogram mathematical model before the end of surgery for predicting lymph node metastasis in patients with early invasive lung adenocarcinoma. METHODS: In this study, we included patients with invasive lung adenocarcinoma measuring ≤ 2 cm who underwent pulmonary resection with definite pathology at Qilu Hospital of Shandong University from January 2020 to January 2022. Preoperative biomarker results, clinical features, and computed tomography characteristics were collected. The enrolled patients were randomized into a training cohort and a validation cohort in a 7:3 ratio. The training cohort was used to construct the predictive model, while the validation cohort was used to test the model independently. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors. The prediction model and nomogram were established based on the independent risk factors. Recipient operating characteristic (ROC) curves were used to assess the discrimination ability of the model. Calibration capability was assessed using the Hosmer-Lemeshow test and calibration curves. The clinical utility of the nomogram was assessed using decision curve analysis (DCA). RESULTS: The overall incidence of lymph node metastasis was 13.23% (61/461). Six indicators were finally determined to be independently associated with lymph node metastasis. These six indicators were: age (P < 0.001), serum amyloid (SA) (P = 0.008); carcinoma antigen 125 (CA125) (P = 0. 042); mucus composition (P = 0.003); novel aspartic proteinase of the pepsin family A (Napsin A) (P = 0.007); and cytokeratin 5/6 (CK5/6) (P = 0.042). The area under the ROC curve (AUC) was 0.843 (95% CI: 0.779-0.908) in the training cohort and 0.838 (95% CI: 0.748-0.927) in the validation cohort. the P-value of the Hosmer-Lemeshow test was 0.0613 in the training cohort and 0.8628 in the validation cohort. the bias of the training cohort corrected C-index was 0.8444 and the bias-corrected C-index for the validation cohort was 0.8375. demonstrating that the prediction model has good discriminative power and good calibration. CONCLUSIONS: The column line graphs created showed excellent discrimination and calibration to predict lymph node status in patients with ≤ 2 cm invasive lung adenocarcinoma. In addition, the predictive model has predictive potential before the end of surgery and can inform clinical decision making.


Asunto(s)
Adenocarcinoma del Pulmón , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Adenocarcinoma/cirugía , Inmunohistoquímica , Metástasis Linfática , Nomogramas , Estudios Retrospectivos
18.
Cancer Control ; 31: 10732748241250208, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38716756

RESUMEN

Nasopharyngeal Carcinoma (NC) refers to the malignant tumor that occurs at the top and side walls of the nasopharyngeal cavity. The NC incidence rate always dominates the first among the malignant tumors of the ear, nose and throat, and mainly occurs in Asia. NC cases are mainly concentrated in southern provinces in China, with about 4 million existing NC. With the pollution of environment and pickled diet, and the increase of life pressure, the domestic NC incidence rate has reached 4.5-6.5/100000 and is increasing year by year. It was reported that the known main causes of NC include hereditary factor, genetic mutations, and EB virus infection, common clinical symptoms of NC include nasal congestion, bloody mucus, etc. About 90% of NC is highly sensitive to radiotherapy which is regard as the preferred treatment method; However, for NC with lower differentiation, larger volume, and recurrence after treatment, surgical resection and local protons and heavy ions therapy are also indispensable means. According to reports, the subtle heterogeneity and diversity exists in some NC, with about 80% of NC undergone radiotherapy and about 25% experienced recurrence and death within five years after radiotherapy in China. Therefore, screening the NC population with suspected recurrence after concurrent chemoradiotherapy may improve survival rates in current clinical decision-making.


NC is one of the prevalent malignancies of the head and neck region with poor prognosis. The aim of this study is to establish a predictive model for assessing NC prognosis using clinical and MR radiomics data.


Asunto(s)
Quimioradioterapia , Imagen por Resonancia Magnética , Neoplasias Nasofaríngeas , Recurrencia Local de Neoplasia , Humanos , Neoplasias Nasofaríngeas/terapia , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/diagnóstico por imagen , Quimioradioterapia/métodos , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/patología , Estudios Retrospectivos , Masculino , Persona de Mediana Edad , Imagen por Resonancia Magnética/métodos , Femenino , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/diagnóstico por imagen , Adulto , China/epidemiología , Metástasis de la Neoplasia , Anciano , Radiómica
19.
J Org Chem ; 89(11): 7780-7789, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38752832

RESUMEN

Methods for regioselective N-trideuteromethylation of tautomeric polyaza heterocycles are highly sought-after. Disclosed herein is an N-trideuterated methylation reaction of imidazoles and pyrazoles with high regioselectivity and deuterium purity using easily available CF3SO3CD3 as the -CD3 source. This method enables the easy synthesis of important deuterium-labeled azoles, including dimetridazole-d3, ipronidazole-d3, hydroxy dimetridazole-d3, and ronidazole-d3.

20.
Macromol Rapid Commun ; : e2400251, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38813898

RESUMEN

Core-shell tecto dendrimers (CSTDs) with excellent physicochemical properties and good tumor penetration and gene transfection efficiency have been demonstrated to have the potential to replace high-generation dendrimers in biomedical applications. However, their characterization and related biological properties of CSTDs for enhanced tumor penetration and gene delivery still lack in-depth investigation. Herein, three types of dual-responsive CSTDs are designed for thorough physicochemical characterization and investigation of their tumor penetration and gene delivery efficiency. Three types of CSTDs are prepared through phenylborate ester bonds of phenylboronic acid (PBA)-decorated generation 5 (G5) poly(amidoamine) (PAMAM) dendrimers as cores and monose (galactose, glucose, or mannose)-conjugated G3 PAMAM dendrimers as shells and thoroughly characterized via NMR and other techniques. It is shown that the produced CSTDs display strong correlation signals between the PBA and monose protons, similar hydrodynamic diameters, and dual reactive oxygen species- and pH-responsivenesses. The dual-responsive CSTDs are proven to have structure-dependent tumor penetration property and gene delivery efficiency in terms of small interference RNA for gene silencing and plasmid DNA for gene editing, thus revealing a great potential for different biomedical applications.

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