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1.
Nature ; 610(7930): 54-60, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36171286

RESUMEN

Integrated photonics has profoundly affected a wide range of technologies underpinning modern society1-4. The ability to fabricate a complete optical system on a chip offers unrivalled scalability, weight, cost and power efficiency5,6. Over the last decade, the progression from pure III-V materials platforms to silicon photonics has significantly broadened the scope of integrated photonics, by combining integrated lasers with the high-volume, advanced fabrication capabilities of the commercial electronics industry7,8. Yet, despite remarkable manufacturing advantages, reliance on silicon-based waveguides currently limits the spectral window available to photonic integrated circuits (PICs). Here, we present a new generation of integrated photonics by directly uniting III-V materials with silicon nitride waveguides on Si wafers. Using this technology, we present a fully integrated PIC at photon energies greater than the bandgap of silicon, demonstrating essential photonic building blocks, including lasers, amplifiers, photodetectors, modulators and passives, all operating at submicrometre wavelengths. Using this platform, we achieve unprecedented coherence and tunability in an integrated laser at short wavelength. Furthermore, by making use of this higher photon energy, we demonstrate superb high-temperature performance and kHz-level fundamental linewidths at elevated temperatures. Given the many potential applications at short wavelengths, the success of this integration strategy unlocks a broad range of new integrated photonics applications.

2.
Proc Natl Acad Sci U S A ; 120(31): e2216543120, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37487096

RESUMEN

Most phenylpropanoid pathway flux is directed toward the production of monolignols, but this pathway also generates multiple bioactive metabolites. The monolignols coniferyl and sinapyl alcohol polymerize to form guaiacyl (G) and syringyl (S) units in lignin, components that are characteristic of plant secondary cell walls. Lignin negatively impacts the saccharification potential of lignocellulosic biomass. Although manipulation of its content and composition through genetic engineering has reduced biomass recalcitrance, in some cases, these genetic manipulations lead to impaired growth. The reduced-growth phenotype is often attributed to poor water transport due to xylem collapse in low-lignin mutants, but alternative models suggest that it could be caused by the hyper- or hypoaccumulation of phenylpropanoid intermediates. In Arabidopsis thaliana, overexpression of FERULATE 5-HYDROXYLASE (F5H) shifts the normal G/S lignin ratio to nearly pure S lignin and does not result in substantial changes to plant growth. In contrast, when we overexpressed F5H in the low-lignin mutants cinnamyl dehydrogenase c and d (cadc cadd), cinnamoyl-CoA reductase 1, and reduced epidermal fluorescence 3, plant growth was severely compromised. In addition, cadc cadd plants overexpressing F5H exhibited defects in lateral root development. Exogenous coniferyl alcohol (CA) and its dimeric coupling product, pinoresinol, rescue these phenotypes. These data suggest that mutations in the phenylpropanoid pathway limit the biosynthesis of pinoresinol, and this effect is exacerbated by overexpression of F5H, which further draws down cellular pools of its precursor, CA. Overall, these genetic manipulations appear to restrict the synthesis of pinoresinol or a downstream metabolite that is necessary for plant growth.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Oxigenasas de Función Mixta/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Lignina/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Fenotipo , Regulación de la Expresión Génica de las Plantas
3.
J Biol Chem ; 299(8): 105035, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37442234

RESUMEN

Neurosteroids, which are steroids synthesized by the nervous system, can exert neuromodulatory and neuroprotective effects via genomic and nongenomic pathways. The neurosteroid and major steroid precursor pregnenolone has therapeutical potential in various diseases, such as psychiatric and pain disorders, and may play important roles in myelination, neuroinflammation, neurotransmission, and neuroplasticity. Although pregnenolone is synthesized by CYP11A1 in peripheral steroidogenic organs, our recent study showed that pregnenolone must be synthesized by another mitochondrial cytochrome P450 (CYP450) enzyme other than CYP11A1 in human glial cells. Therefore, we sought to identify the CYP450 responsible for pregnenolone production in the human brain. Upon screening for CYP450s expressed in the human brain that have mitochondrial localization, we identified three enzyme candidates: CYP27A1, CYP1A1, and CYP1B1. We found that inhibition of CYP27A1 through inhibitors and siRNA knockdown did not negatively affect pregnenolone synthesis in human glial cells. Meanwhile, treatment of human glial cells with CYP1A1/CYP1B1 inhibitors significantly reduced pregnenolone production in the presence of 22(R)-hydroxycholesterol. We performed siRNA knockdown of CYP1A1 or CYP1B1 in human glial cells and found that only CYP1B1 knockdown significantly decreased pregnenolone production. Furthermore, overexpression of mitochondria-targeted CYP1B1 significantly increased pregnenolone production under basal conditions and in the presence of hydroxycholesterols and low-density lipoprotein. Inhibition of CYP1A1 and/or CYP1B1 via inhibitors or siRNA knockdown did not significantly reduce pregnenolone synthesis in human adrenal cortical cells, implying that CYP1B1 is not a major pregnenolone-producing enzyme in the periphery. These data suggest that mitochondrial CYP1B1 is involved in pregnenolone synthesis in human glial cells.


Asunto(s)
Enzima de Desdoblamiento de la Cadena Lateral del Colesterol , Citocromo P-450 CYP1B1 , Pregnenolona , Humanos , Encéfalo/metabolismo , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1B1/metabolismo , Hidroxicolesteroles/metabolismo , Mitocondrias/metabolismo , Neuroglía/metabolismo , Pregnenolona/biosíntesis , ARN Interferente Pequeño/metabolismo , Esteroides/metabolismo
4.
Plant J ; 114(6): 1490-1505, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36971060

RESUMEN

Australian pine (Casuarina spp.) is extensively planted in tropical and subtropical regions for wood production, shelterbelts, environmental protection, and ecological restoration due to their superior biological characteristics, such as rapid growth, wind and salt tolerance, and nitrogen fixation. To analyze the genomic diversity of Casuarina, we sequenced the genomes and constructed de novo genome assemblies of the three most widely planted Casuarina species: C. equisetifolia, C. glauca, and C. cunninghamiana. We generated chromosome-scale genome sequences using both Pacific Biosciences (PacBio) Sequel sequencing and chromosome conformation capture technology (Hi-C). The total genome sizes for C. equisetifolia, C. glauca, and C. cunninghamiana are 268 942 579 bp, 296 631 783 bp, and 293 483 606 bp, respectively, of which 25.91, 27.15, and 27.74% were annotated as repetitive sequences. We annotated 23 162, 24 673, and 24 674 protein-coding genes in C. equisetifolia, C. glauca, and C. cunninghamiana, respectively. We then collected branchlets from male and female individuals for whole-genome bisulfite sequencing (BS-seq) to explore the epigenetic regulation of sex determination in these three species. Transcriptome sequencing (RNA-seq) revealed differential expression of phytohormone-related genes between male and female plants. In summary, we generated three chromosome-level genome assemblies and comprehensive DNA methylation and transcriptome datasets from both male and female material for three Casuarina species, providing a basis for the comprehensive investigation of genomic diversity and functional gene discovery of Casuarina in the future.


Asunto(s)
Cromosomas , Epigénesis Genética , Australia , Secuencia de Bases , Secuencias Repetitivas de Ácidos Nucleicos , Anotación de Secuencia Molecular
5.
Pflugers Arch ; 476(5): 755-767, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38305876

RESUMEN

It has been suggested that the novel selective phosphodiesterase 9 (PDE9) inhibitor may improve cardiac and renal function by blocking 3',5'-cyclic guanosine monophosphate (cGMP) degradation. 5/6 nephrectomized (5/6Nx) rats were used to investigate the effects of the PDE9 inhibitor (BAY 73-6691) on the heart and kidney. Two doses of BAY 73-6691 (1 mg/kg/day and 5 mg/kg/day) were given for 95 days. The 5/6Nx rats developed albuminuria, a decrease in serum creatinine clearance (Ccr), and elevated serum troponin T levels. Echocardiographic data showed that 5/6 nephrectomy resulted in increased fractional shortening (FS), stroke volume (SV), and left ventricular ejection fraction (EF). However, 95 days of PDE9 inhibitor treatment did not improve any cardiac and renal functional parameter. Histopathologically, 5/6 nephrectomy resulted in severe kidney and heart damage, such as renal interstitial fibrosis, glomerulosclerosis, and enlarged cardiomyocytes. Telmisartan attenuated renal interstitial fibrosis and glomerulosclerosis as well as improved cardiomyocyte size. However, except for cardiomyocyte size and renal perivascular fibrosis, BAY 73-6691 had no effect on other cardiac and renal histologic parameters. Pathway enrichment analysis using RNA sequencing data of kidney and heart tissue identified chronic kidney disease pathways, such as phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) signaling pathway, complement and coagulation cascades, and nuclear factor kappa B (NF-κB) signaling pathway. PDE9i did not affect any of these disease-related pathways. Two dosages of the PDE9 inhibitor BAY 73-6691 known to be effective in other rat models have only limited cardio-renal protective effects in 5/6 nephrectomized rats.


Asunto(s)
Corazón , Riñón , Nefrectomía , Animales , Masculino , Ratas , Corazón/efectos de los fármacos , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Miocardio/metabolismo , Miocardio/patología , Nefrectomía/métodos
6.
J Am Chem Soc ; 146(1): 330-341, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38113388

RESUMEN

Implementing dissipative assembly in living systems is meaningful for creation of living materials or even artificial life. However, intracellular dissipative assembly remains scarce and is significantly impeded by the challenges lying in precisely operating chemical reaction cycles under complex physiological conditions. Here, we develop organelle-mediated dissipative self-assembly of peptides in living cells fueled by GSH, via the design of a mitochondrion-targeting and redox-responsive hexapeptide. While the hexapeptide undergoes efficient redox-responsive self-assembly, the addition of GSH into the peptide solution in the presence of mitochondrion-biomimetic liposomes containing hydrogen peroxide allows for transient assembly of peptides. Internalization of the peptide by LPS-stimulated macrophages leads to the self-assembly of the peptide driven by GSH reduction and the association of the peptide assemblies with mitochondria. The association facilitates reversible oxidation of the reduced peptide by mitochondrion-residing ROS and thereby dissociates the peptide from mitochondria to re-enter the cytoplasm for GSH reduction. The metastable peptide-mitochondrion complexes prevent the thermodynamically equilibrated self-assembly, thus establishing dissipative assembly of peptides in stimulated macrophages. The entire dissipative self-assembling process allows for elimination of elevated ROS and decrease of pro-inflammatory cytokine expression. Creating dissipative self-assembling systems assisted by internal structures provides new avenues for the development of living materials or medical agents in the future.


Asunto(s)
Mitocondrias , Péptidos , Especies Reactivas de Oxígeno , Péptidos/química
7.
J Am Chem Soc ; 146(15): 10753-10766, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38578841

RESUMEN

Proteolysis targeting chimera (PROTAC) technology is an innovative strategy for cancer therapy, which, however, suffers from poor targeting delivery and limited capability for protein of interest (POI) degradation. Here, we report a strategy for the in situ formulation of antineoplastic Supra-PROTACs via intracellular sulfatase-responsive assembly of peptides. Coassembling a sulfated peptide with two ligands binding to ubiquitin VHL and Bcl-xL leads to the formation of a pro-Supra-PROTAC, in which the ratio of the two ligands is rationally optimized based on their protein binding affinity. The resulting pro-Supra-PROTAC precisely undergoes enzyme-responsive assembly into nanofibrous Supra-PROTACs in cancer cells overexpressing sulfatase. Mechanistic studies reveal that the pro-Supra-PROTACs selectively cause apparent cytotoxicity to cancer cells through the degradation of Bcl-xL and the activation of caspase-dependent apoptosis, during which the rationally optimized ligand ratio improves the bioactivity for POI degradation and cell death. In vivo studies show that in situ formulation enhanced the tumor accumulation and retention of the pro-Supra-PROTACs, as well as the capability for inhibiting tumor growth with excellent biosafety when coadministrating with chemodrugs. Our findings provide a new approach for enzyme-regulated assembly of peptides in living cells and the development of PROTACs with high targeting delivering and POI degradation efficiency.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Quimera Dirigida a la Proteólisis , Antineoplásicos/farmacología , Sulfatasas , Proteolisis , Péptidos , Ubiquitina-Proteína Ligasas
8.
J Am Chem Soc ; 146(34): 24177-24187, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39140408

RESUMEN

Despite significant progress achieved in artificial self-sorting in solution, operating self-sorting in the body remains a considerable challenge. Here, we report an in vivo self-sorting peptide system via an in situ assembly evolution for combined cancer therapy. The peptide E3C16-SS-EIY consists of two disulfide-connected segments, E3C16SH and SHEIY, capable of independent assembly into twisted or flat nanoribbons. While E3C16-SS-EIY assembles into nanorods, exposure to glutathione (GSH) leads to the conversion of the peptide into E3C16SH and SHEIY, thus promoting in situ evolution from the nanorods into self-sorted nanoribbons. Furthermore, incorporation of two ligand moieties targeting antiapoptotic protein XIAP and organellar endoplasmic reticulum (ER) into the self-sorted nanoribbons allows for simultaneous inhibition of XIAP and accumulation surrounding ER. This leads to the cytotoxicity toward the cancer cells with elevated GSH levels, through activating caspase-dependent apoptosis and inducing ER dysfunction. In vivo self-sorting of E3C16-SS-EIY decorated with ligand moieties is thoroughly validated by tissue studies. Tumor-bearing mouse experiments confirm the therapeutic efficacy of the self-sorted assemblies for inhibiting tumor growth, with excellent biosafety. Our findings demonstrate an efficient approach to develop in vivo self-sorting systems and thereby facilitating in situ formulation of biomedical agents.


Asunto(s)
Péptidos , Humanos , Animales , Péptidos/química , Péptidos/farmacología , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proteína Inhibidora de la Apoptosis Ligada a X/antagonistas & inhibidores , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Glutatión/química , Glutatión/metabolismo , Línea Celular Tumoral , Nanotubos/química
9.
BMC Med ; 22(1): 342, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39183296

RESUMEN

BACKGROUND: Early detection and treatment are effective methods for the management of oral squamous cell carcinoma (OSCC), which can be facilitated by the detection of tumor-specific OSCC biomarkers. The epidermal growth factor receptor (EGFR) and programmed death-ligand 1 (PD-L1) are important therapeutic targets for OSCC. Multispectral fluorescence molecular imaging (FMI) can facilitate the detection of tumor multitarget expression with high sensitivity and safety. Hence, we developed Nimotuzumab-ICG and Atezolizumab-Cy5.5 imaging probes, in combination with multispectral FMI, to sensitively and noninvasively identify EGFR and PD-L1 expression for the detection and comprehensive treatment of OSCC. METHODS: The expression of EGFR and PD-L1 was analyzed using bioinformatics data sources and specimens. Nimotuzumab-ICG and Atezolizumab-Cy5.5 imaging probes were developed and tested on preclinical OSCC cell line and orthotopic OSCC mouse model, fresh OSCC patients' biopsied samples, and further clinical mouthwash trials were conducted in OSCC patients. RESULTS: EGFR and PD-L1 were specifically expressed in human OSCC cell lines and tumor xenografts. Nimotuzumab-ICG and Atezolizumab-Cy5.5 imaging probes can specifically target to the tumor sites in an in situ human OSCC mouse model with good safety. The detection sensitivity and specificity of Nimotuzumab-ICG in patients were 96.4% and 100%, and 95.2% and 88.9% for Atezolizumab-Cy5.5. CONCLUSIONS: EGFR and PD-L1 are highly expressed in OSCC, the combination of which is important for a precise prognosis of OSCC. EGFR and PD-L1 expression can be sensitively detected using the newly synthesized multispectral fluorescence imaging probes Nimotuzumab-ICG and Atezolizumab-Cy5.5, which can facilitate the sensitive and specific detection of OSCC and improve treatment outcomes. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2100045738. Registered 23 April 2021, https://www.chictr.org.cn/bin/project/edit?pid=125220.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antígeno B7-H1 , Carcinoma de Células Escamosas , Receptores ErbB , Neoplasias de la Boca , Imagen Óptica , Humanos , Antígeno B7-H1/metabolismo , Animales , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/diagnóstico , Imagen Óptica/métodos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Ratones , Femenino , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/diagnóstico , Masculino , Línea Celular Tumoral , Persona de Mediana Edad , Imagen Molecular/métodos , Biomarcadores de Tumor/metabolismo
10.
Small ; 20(28): e2309328, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38308407

RESUMEN

Chirality is a prevalent characteristic in nature, where biological systems exhibit a significant preference for specific enantiomers of biomolecules. However, there is a limited exploration into utilizing nanomaterials' chirality to modulate their interactions with intracellular substances. In this study, self-assembled copper-cysteine chiral nanoparticles and explore the influence of their charity on cancer chemodynamic therapy (CDT) are fabricated. Experimental and molecular dynamics (MD) simulation results demonstrate that the copper-l-cysteine chiral nanoparticles (Cu-l-Cys NPs) exhibit a stronger affinity toward l-glutathione (l-GSH) that is overproduced in cancer cells, compared to the copper-d-cysteine enantiomer (Cu-d-Cys NPs). The interaction between Cu-l-Cys NPs and l-GSH triggers a redox reaction that depletes l-GSH and converts Cu2+ into Cu+. Subsequently, Cu+ catalyzes a Fenton-like reaction, decomposing H2O2 into highly cytotoxic hydroxyl radicals (•OH) for cancer CDT. In vivo, results confirm that Cu-l-Cys NPs with good biocompatibility elicit a pronounced cancer cell death and effectively inhibit tumor growth. This work proposes a new perspective on chirality-enhanced cancer therapy.


Asunto(s)
Cobre , Nanopartículas , Neoplasias , Cobre/química , Humanos , Nanopartículas/química , Animales , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neoplasias/metabolismo , Aminoácidos/química , Glutatión/química , Glutatión/metabolismo , Línea Celular Tumoral , Cisteína/química , Simulación de Dinámica Molecular , Ratones , Estereoisomerismo
11.
J Virol ; 97(8): e0070023, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37578239

RESUMEN

Human adenovirus (HAdV) is ubiquitous in the human population, constituting a significant burden of global respiratory diseases. Children and individuals with low immunity are at risk of developing severe infections without approved antiviral treatment for HAdV. Our study demonstrated that TRIM35 inhibited HAdV-C5 early gene transcription, early protein expression, genome replication, and infectious virus progeny production. Furthermore, TRIM35 was found to inhibit HAdV replication by attenuating E1A expression. Mechanistically, TRIM35 interacts with and degrades E1A by promoting its K48-linked ubiquitination. Additionally, K253 and K285 are the key sites necessary for TRIM35 degradation. Moreover, an oncolytic adenovirus carrying shTRIM35 was constructed and observed to exhibit improved oncolysis in vivo, providing new ideas for clinical tumor treatment. Our results expand the broad antiviral activity of TRIM35 and mechanically support its application as a HAdV replication inhibitor. IMPORTANCE E1A is an essential human adenovirus (HAdV) protein responsible for the early replication of adenovirus while interacting with multiple host proteins. Understanding the interaction between HAdV E1A and TRIM35 helps identify effective antiviral therapeutic targets. The viral E1A protein is a crucial activator and regulator of viral transcription during the early infection stages. We first reported that TRIM35 interacts with E1A to resist adenovirus infection. Our study demonstrated that TRIM35 targets E1A to resist adenovirus, indicating the applicability of targeting virus-dependent host factors as a suitable antiviral strategy.


Asunto(s)
Proteínas E1A de Adenovirus , Adenovirus Humanos , Proteínas Reguladoras de la Apoptosis , Replicación Viral , Humanos , Proteínas E1A de Adenovirus/genética , Proteínas E1A de Adenovirus/metabolismo , Adenovirus Humanos/fisiología , Antivirales/farmacología , Proteínas Reguladoras de la Apoptosis/metabolismo
12.
Bioinformatics ; 39(1)2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36342236

RESUMEN

MOTIVATION: Virus mutation is one of the most important research issues which plays a critical role in disease progression and has prompted substantial scientific publications. Mutation extraction from published literature has become an increasingly important task, benefiting many downstream applications such as vaccine design and drug usage. However, most existing approaches have low performances in extracting virus mutation due to both lack of precise virus mutation information and their development based on human gene mutations. RESULTS: We developed ViMRT, a text-mining tool and search engine for automated virus mutation recognition using natural language processing. ViMRT mainly developed 8 optimized rules and 12 regular expressions based on a development dataset comprising 830 papers of 5 human severe disease-related viruses. It achieved higher performance than other tools in a test dataset (1662 papers, 99.17% in F1-score) and has been applied well to two other viruses, influenza virus and severe acute respiratory syndrome coronavirus-2 (212 papers, 96.99% in F1-score). These results indicate that ViMRT is a high-performance method for the extraction of virus mutation from the biomedical literature. Besides, we present a search engine for researchers to quickly find and accurately search virus mutation-related information including virus genes and related diseases. AVAILABILITY AND IMPLEMENTATION: ViMRT software is freely available at http://bmtongji.cn:1225/mutation/index.


Asunto(s)
Minería de Datos , Virus , Minería de Datos/métodos , Mutación , Motor de Búsqueda , Virus/genética
13.
Plant Physiol ; 191(2): 1017-1035, 2023 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-36417282

RESUMEN

The fast growth of Moso bamboo (Phyllostachys edulis) shoots is caused by the rapid elongation of each internode. However, the key underlying cellular processes and epigenetic mechanisms remain largely unexplored. We used microscopy and multi-omics approaches to investigate two regions (bottom and middle) of the 18th internode from shoots of two different heights (2 and 4 m). We observed that internode cells become longer, and that lignin biosynthesis and glycosyltransferase family 43 (GT43) genes are substantially upregulated with shoot height. Nanopore direct RNA sequencing (DRS) revealed a higher N6-methyladenine (m6A) modification rate in 2-m shoots than in 4-m shoots. In addition, different specific m6A modification sites were enriched at different growth stages. Global DNA methylation profiling indicated that DNA methylation levels are higher in 4-m shoots than in 2-m shoots. We also detected shorter poly(A) tail lengths (PALs) in 4-m shoots compared with 2-m shoots. Genes showing differential PAL were mainly enriched in the functional terms of protein translation and vesicle fusion. An association analysis between PALs and DNA methylation strongly suggested that gene body CG methylation levels are positively associated with PAL. This study provides valuable information to better understand post-transcriptional regulations responsible for fast-growing shoots in Moso bamboo.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Poaceae , Brotes de la Planta/metabolismo , Poaceae/genética , ARN/metabolismo , Epigénesis Genética
14.
Ann Surg Oncol ; 31(4): 2451-2460, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38063990

RESUMEN

BACKGROUND: We compare the application of intravenous indocyanine green (ICG) fluorescence imaging in lung cancer with near-infrared-I (NIR-I) and near-infrared-II (NIR-II) windows. METHODS: From March to December 2022, we enrolled patients who received an intravenous injection of ICG (5 mg/kg) 1 day before the planned lung cancer surgery. The lung cancer nodules were imaged by NIR-I/II fluorescence imaging systems, and the tumor-to-normal-tissue ratio (TNR) was calculated. In addition, the fluorescence intensity and signal-to-background ratio (SBR) of capillary glass tubes containing ICG covered with different thicknesses of lung tissue were measured by NIR-I/II fluorescence imaging systems. RESULTS: In this study, 102 patients were enrolled, and the mean age was 59.9 ± 9.2 years. A total of 96 (94.1%) and 98 (96.1%) lung nodules were successfully imaged with NIR-I and NIR-II fluorescence, and the TNR of NIR-II was significantly higher than that of NIR-I (3.9 ± 1.3 versus 2.4 ± 0.6, P < 0.001). In multiple linear regression, solid nodules (P < 0.001) and squamous cell carcinoma (P < 0.001) were independent predictors of a higher TNR of NIR-I/II. When capillary glass tubes were covered with lung tissue whose thickness was more than 2 mm, the fluorescence intensity and the SBR of NIR-II were significantly higher than those of NIR-I. CONCLUSIONS: We verified the feasibility of NIR-II fluorescence imaging in intravenous ICG lung cancer imaging for the first time. NIR-II fluorescence can improve the TNR and penetration depth of lung cancer with promising clinical prospects.


Asunto(s)
Verde de Indocianina , Neoplasias Pulmonares , Humanos , Persona de Mediana Edad , Anciano , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Imagen Óptica/métodos , Pulmón , Fluorescencia
15.
Acc Chem Res ; 56(21): 2992-2999, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37847868

RESUMEN

The development of various chemical methods has enabled scientists to decipher the distribution features and biological functions of RNA modifications in the past decade. In addition to modifying noncoding RNAs such as tRNAs and rRNAs, N6-methyladenosine (m6A) has been proven to be the most abundant internal chemical modification on mRNAs in eukaryotic cells and is also the most widely studied mRNA modification to date. Extensive studies have repeatedly demonstrated the important functions of m6A in various biological conditions, ranging from embryonic organ development to adult organ function and pathogenesis. Unlike DNA methylation which is relatively stable, the reversible m6A modification on mRNA is highly dynamic and easily influenced by various internal or external factors, such as cell type, developmental stage, nutrient supply, circadian rhythm, and environmental stresses.In this Account, we review our previous findings on the site selectivity mechanisms regulating m6A formation, as well as the physiological roles of m6A modification in cerebellum development and long-term memory consolidation. In our initial efforts to profile m6A in various types of mouse and human cells, we surprisingly found that the sequence motifs surrounding m6A sites were often complementary with the seed sequences of miRNAs. By manipulating the abundance of the miRNA biogenesis enzyme Dicer or individual miRNAs or mutating miRNA sequences, we were able to reveal a new role of nucleus localized miRNAs, which is to guide the m6A methyltransferase METTL3 to bind to mRNAs and to promote m6A formation. As a result, we partially answered the question of why only a small proportion of m6A motifs within an mRNA could have m6A modification at a certain time point. We further explored the functions of m6A modification in regulating brain development and brain functions. We found that cerebellum had the most severe defects when Mettl3 was knocked out in developing mouse embryonic brain and revealed that the underlying mechanisms could be attributed to aberrant mRNA splicing and enhanced cell apoptosis under m6A deficit conditions. On the other hand, knocking out Mettl3 in postnatal hippocampus did not cause morphological defects in the mouse brain but impaired the efficacy of long-term memory consolidation. Under learning stimuli, formation of m6A modifications could be detected on transcripts encoding proteins related to dendrite growth, synapse formation, and other memory related functions. Loss of m6A modifications on these transcripts would result in translation deficiency and reduced protein production, particularly in the translation of early response genes, and therefore would compromise the efficacy of long-term memory consolidation. Interestingly, excessive training sessions or increased training intensity could overcome such m6A deficiency related memory defects, which is likely due to the longer turnover cycle and the cumulative abundance of proteins throughout the training process. In addition to revealing the roles of m6A modification in regulating long-term memory formation, our work also demonstrated an effective method for studying memory formation efficacy. As the lack of an appropriate model for studying memory formation efficacy has been a long-lasting problem in the field of neural science, our hippocampus-specific postnatal m6A knockout model could also be utilized to study other questions related to memory formation efficacy.


Asunto(s)
Metiltransferasas , MicroARNs , Animales , Humanos , Ratones , Adenosina/metabolismo , Metilación , Metiltransferasas/metabolismo , MicroARNs/metabolismo , ARN Mensajero/metabolismo
16.
EMBO Rep ; 23(2): e53081, 2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-34866316

RESUMEN

Mouse embryonic stem cells (mESCs) can self-renew indefinitely and maintain pluripotency. Inhibition of mechanistic target of rapamycin (mTOR) by the kinase inhibitor INK128 is known to induce paused pluripotency in mESCs cultured with traditional serum/LIF medium (SL), but the underlying mechanisms remain unclear. In this study, we demonstrate that mTOR complex 1 (mTORC1) but not complex 2 (mTORC2) mediates mTOR inhibition-induced paused pluripotency in cells grown in both SL and 2iL medium (GSK3 and MEK inhibitors and LIF). We also show that mTORC1 regulates self-renewal in both conditions mainly through eIF4F-mediated translation initiation that targets mRNAs of both cytosolic and mitochondrial ribosome subunits. Moreover, inhibition of mitochondrial translation is sufficient to induce paused pluripotency. Interestingly, eIF4F also regulates maintenance of pluripotency in an mTORC1-independent but MEK/ERK-dependent manner in SL, indicating that translation of pluripotency genes is controlled differently in SL and 2iL. Our study reveals a detailed picture of how mTOR governs self-renewal in mESCs and uncovers a context-dependent function of eIF4F in pluripotency regulation.


Asunto(s)
Factor 4F Eucariótico de Iniciación , Diana Mecanicista del Complejo 1 de la Rapamicina , Células Madre Embrionarias de Ratones/citología , Células Madre Pluripotentes/citología , Animales , Factor 4F Eucariótico de Iniciación/genética , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Diana Mecanicista del Complejo 2 de la Rapamicina , Ratones
17.
Inorg Chem ; 63(26): 12231-12239, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38901842

RESUMEN

Keggin-type polyoxometalate (POM) supported single transition metal (TM) atom (TM1/POM) as an efficient soluble redox mediator for Li-O2 batteries is comprehensively investigated by first-principles calculations. Among the pristine POM and four kinds of TM1/POM (TM = Fe, Co, Ni, and Pt), Co1/POM not only maintains good structural and thermodynamic stability in oxidized and reduced states but also exhibits promising electro(chemical) catalytic performance for both oxygen reduction reaction and oxygen evolution reaction (OER) in Li-O2 batteries with the lowest Gibbs free energy barriers. Further investigations demonstrate that the moderate binding strength of Li2-xO2 (x = 0, 1, and 2) intermediates on Co1/POM guarantees favorable Li2O2 formation and decomposition. Electronic structure analyses indicate that the introduced Co single atom as an electron transfer bridge can not only efficiently improve the electronic conductivity of POM but also regulate the bonding/antibonding states around the Fermi level of [Co1/POM-Li2O2]ox. The solvent effect on the OER catalytic performance and the electronic properties of [Co1/POM-Li2O2]ox with and without dimethyl sulfoxide solvent are also investigated.

18.
Phys Chem Chem Phys ; 26(23): 16838-16846, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38832413

RESUMEN

As a key configuration, hard carbon (HC) is widely regarded as a promising cathode for rechargeable aluminum batteries (RABs), because of its enlarged interlayer spacing and well-developed pore structures. However, the trade-off between the pore structure, interlayer spacing and conductivity easily leads to an unsatisfactory electrochemical performance in terms of capacity and cycling stability. Hence, N-doped hard carbon (P-M) is synthesized at a relatively low temperature (700 °C) and anion intercalation associated with the energy storage process is investigated. The results demonstrate that the introduction of a N-doping agent not only expands the layer spacing and creates rich pore structures, but also boosts the conductivity. Compared with HC without N-doping, the expanded interlayer spacing in P-M can increase ion storage ability, and the rich pore channels contribute to electron transfer. Besides, compared with HC annealed at a higher temperature (900 °C), the enhanced conductivity in P-M is conducive to accelerating ion diffusion. Benefiting from these structure merits, the optimized P-M cathode delivers a high capacity (323 mA h g-1 at 500 mA g-1) and a prolonged cycle lifespan over 1000 cycles at 1 A g-1 retaining 109 mA h g-1. This work can provide a guidance for developing other high-performance hard carbon cathodes.

19.
Nucleic Acids Res ; 50(D1): D918-D927, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34500462

RESUMEN

Molecular mechanisms of virus-related diseases involve multiple factors, including viral mutation accumulation and integration of a viral genome into the host DNA. With increasing attention being paid to virus-mediated pathogenesis and the development of many useful technologies to identify virus mutations (VMs) and viral integration sites (VISs), much research on these topics is available in PubMed. However, knowledge of VMs and VISs is widely scattered in numerous published papers which lack standardization, integration and curation. To address these challenges, we built a pilot database of human disease-related Virus Mutations, Integration sites and Cis-effects (ViMIC), which specializes in three features: virus mutation sites, viral integration sites and target genes. In total, the ViMIC provides information on 31 712 VMs entries, 105 624 VISs, 16 310 viral target genes and 1 110 015 virus sequences of eight viruses in 77 human diseases obtained from the public domain. Furthermore, in ViMIC users are allowed to explore the cis-effects of virus-host interactions by surveying 78 histone modifications, binding of 1358 transcription regulators and chromatin accessibility on these VISs. We believe ViMIC will become a valuable resource for the virus research community. The database is available at http://bmtongji.cn/ViMIC/index.php.


Asunto(s)
Bases de Datos Factuales , Genoma Viral , Interacciones Huésped-Patógeno/genética , Programas Informáticos , Proteínas Virales/genética , Virosis/genética , Virus/genética , Cromatina/química , Cromatina/metabolismo , Minería de Datos , Regulación de la Expresión Génica , Histonas/genética , Histonas/metabolismo , Humanos , Internet , Mutación , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Virales/metabolismo , Virosis/metabolismo , Virosis/patología , Virosis/virología , Integración Viral/genética , Virus/metabolismo , Virus/patogenicidad
20.
World J Surg Oncol ; 22(1): 52, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38347606

RESUMEN

BACKGROUND: Endoscopic thyroidectomy has been preliminarily proven effective and safe for thyroid diseases. The cosmetic outcomes and life quality are critical contents of postoperative assessment. This review will primarily focus on the assessment methods and results related to cosmetic outcomes, sensory alteration of surgical area, and quality of life following endoscopic thyroidectomy. METHODS: A comprehensive search of published articles within the last decade was conducted using the terms "endoscopic/robotic thyroidectomy," "patient satisfaction scores," "questionnaire," "quality of life," and "cosmetic" in PubMed. RESULTS: Assessment methods for postoperative cosmetic satisfaction and sensory alterations encompassed verbal/visual analog scales, scar evaluations, Semmes-Weinstein monofilament tests, and more. The evaluation of postoperative quality of life in endoscopic thyroidectomy involved tools such as SF-36, SF-12, thyroid-specific questionnaires, thyroid cancer-specific quality of life questionnaires (THYCA-QOL), as well as assessments related to voice and swallow function. The cosmetic results of endoscopic thyroidectomy generally surpassed those of open thyroidectomy, while the quality of life in endoscopic procedures was either superior or equivalent to that in open thyroidectomy, especially with respect to general health, role emotion, and vitality. CONCLUSIONS: Assessments of cosmetic outcomes and sensory alterations following endoscopic thyroidectomy predominantly relied on patients' subjective feelings. The objective and subjective perspectives of scar assessments remain underutilized. In addition, postoperative laryngoscopy and voice function assessments in endoscopic thyroidectomy procedures require more attention.


Asunto(s)
Endoscopía , Satisfacción del Paciente , Calidad de Vida , Tiroidectomía , Humanos , Tiroidectomía/métodos , Tiroidectomía/efectos adversos , Endoscopía/métodos , Cicatriz/psicología , Cicatriz/etiología , Cicatriz/prevención & control , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/psicología , Complicaciones Posoperatorias , Encuestas y Cuestionarios , Pronóstico
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