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1.
Cell ; 160(6): 1196-208, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25728669

RESUMO

Most cell-surface receptors for cytokines and growth factors signal as dimers, but it is unclear whether remodeling receptor dimer topology is a viable strategy to "tune" signaling output. We utilized diabodies (DA) as surrogate ligands in a prototypical dimeric receptor-ligand system, the cytokine Erythropoietin (EPO) and its receptor (EpoR), to dimerize EpoR ectodomains in non-native architectures. Diabody-induced signaling amplitudes varied from full to minimal agonism, and structures of these DA/EpoR complexes differed in EpoR dimer orientation and proximity. Diabodies also elicited biased or differential activation of signaling pathways and gene expression profiles compared to EPO. Non-signaling diabodies inhibited proliferation of erythroid precursors from patients with a myeloproliferative neoplasm due to a constitutively active JAK2V617F mutation. Thus, intracellular oncogenic mutations causing ligand-independent receptor activation can be counteracted by extracellular ligands that re-orient receptors into inactive dimer topologies. This approach has broad applications for tuning signaling output for many dimeric receptor systems.


Assuntos
Receptores da Eritropoetina/química , Receptores da Eritropoetina/metabolismo , Transdução de Sinais , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , Linhagem Celular , Cristalografia por Raios X , Dimerização , Eritropoetina/metabolismo , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Camundongos , Modelos Moleculares , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Mutação Puntual , Engenharia de Proteínas , Receptores da Eritropoetina/agonistas , Receptores da Eritropoetina/antagonistas & inibidores , Alinhamento de Sequência
2.
EMBO J ; 42(23): e114558, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37905571

RESUMO

The Hippo signaling axis is a tumor suppressor pathway that is activated by various extra-pathway factors to regulate cell differentiation and organ development. Recent studies have reported that autophosphorylation of the core kinase cassette stimulates activation of the Hippo signaling cascade. Here, we demonstrate that protein arginine methyltransferase 5 (PRMT5) contributes to inactivation of the Hippo signaling pathway in pancreatic cancer. We show that the Hippo pathway initiator serine/threonine kinase 3 (STK3, also known as MST2) of Hippo signaling pathway can be symmetrically di-methylated by PRMT5 at arginine-461 (R461) and arginine-467 (R467) in its SARAH domain. Methylation suppresses MST2 autophosphorylation and kinase activity by blocking its homodimerization, thereby inactivating Hippo signaling pathway in pancreatic cancer. Moreover, we also show that the specific PRMT5 inhibitor GSK3326595 re-activates the dysregulated Hippo signaling pathway and inhibits the growth of human pancreatic cancer xenografts in immunodeficient mice, thus suggesting potential clinical application of PRMT5 inhibitors in pancreatic cancer.


Assuntos
Via de Sinalização Hippo , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Metilação , Neoplasias Pancreáticas/genética , Arginina/metabolismo , Serina-Treonina Quinase 3 , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Neoplasias Pancreáticas
3.
Plant Cell ; 35(8): 2799-2820, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37132634

RESUMO

Actinomorphic flowers usually orient vertically (relative to the horizon) and possess symmetric nectar guides, while zygomorphic flowers often face horizontally and have asymmetric nectar guides, indicating that floral symmetry, floral orientation, and nectar guide patterning are correlated. The origin of floral zygomorphy is dependent on the dorsoventrally asymmetric expression of CYCLOIDEA (CYC)-like genes. However, how horizontal orientation and asymmetric nectar guides are achieved remains poorly understood. Here, we selected Chirita pumila (Gesneriaceae) as a model plant to explore the molecular bases for these traits. By analyzing gene expression patterns, protein-DNA and protein-protein interactions, and encoded protein functions, we identified multiple roles and functional divergence of 2 CYC-like genes, i.e. CpCYC1 and CpCYC2, in controlling floral symmetry, floral orientation, and nectar guide patterning. CpCYC1 positively regulates its own expression, whereas CpCYC2 does not regulate itself. In addition, CpCYC2 upregulates CpCYC1, while CpCYC1 downregulates CpCYC2. This asymmetric auto-regulation and cross-regulation mechanism might explain the high expression levels of only 1 of these genes. We show that CpCYC1 and CpCYC2 determine asymmetric nectar guide formation, likely by directly repressing the flavonoid synthesis-related gene CpF3'5'H. We further suggest that CYC-like genes play multiple conserved roles in Gesneriaceae. These findings shed light on the repeated origins of zygomorphic flowers in angiosperms.


Assuntos
Magnoliopsida , Néctar de Plantas , Néctar de Plantas/genética , Filogenia , Magnoliopsida/genética , Flores/genética , Genes de Plantas/genética
4.
Cereb Cortex ; 34(3)2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38489786

RESUMO

While it is well known that mental fatigue impairs fine motor performance, the investigation into its neural basis remains scant. Here, we investigate the impact of mental fatigue on fine motor performance and explore its underlying neural network connectivity mechanisms. A total of 24 healthy male university students were recruited and randomly divided into two groups: a mental fatigue group (MF) and a control group (Control). Both groups completed 50 dart throws, while electroencephalography (EEG) data were collected. Following the Stroop intervention, participants in the MF group exhibited a decrease in Stroop task accuracy and throwing performance, and an increase in reaction time along with VAS and NASA scores. The EEG data during dart-throwing revealed that the network connectivity strength of theta oscillations in the frontal and left central regions was significantly higher in the MF group compared with the Control group, while the network connectivity strength of alpha oscillations in the left parietal region was significantly enhanced. The interregional connectivity within the theta and alpha rhythm bands, particularly in the frontal-central-parietal network connections, also showed a significant increase in the MF group. Mental fatigue impairs dart throwing performance and is accompanied by increased connectivity in alpha and theta.


Assuntos
Eletroencefalografia , Lobo Parietal , Humanos , Masculino , Tempo de Reação , Ritmo alfa , Fadiga Mental
5.
Nucleic Acids Res ; 51(D1): D1397-D1404, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36134718

RESUMO

Numerous studies have shown that RNA plays an important role in the occurrence and development of diseases, and RNA-disease associations are not limited to noncoding RNAs in mammals but also exist for protein-coding RNAs. Furthermore, RNA-associated diseases are found across species including plants and nonmammals. To better analyze diseases at the RNA level and facilitate researchers in exploring the pathogenic mechanism of diseases, we decided to update and change MNDR v3.0 to RNADisease v4.0, a repository for RNA-disease association (http://www.rnadisease.org/ or http://www.rna-society.org/mndr/). Compared to the previous version, new features include: (i) expanded data sources and categories of species, RNA types, and diseases; (ii) the addition of a comprehensive analysis of RNAs from thousands of high-throughput sequencing data of cancer samples and normal samples; (iii) the addition of an RNA-disease enrichment tool and (iv) the addition of four RNA-disease prediction tools. In summary, RNADisease v4.0 provides a comprehensive and concise data resource of RNA-disease associations which contains a total of 3 428 058 RNA-disease entries covering 18 RNA types, 117 species and 4090 diseases to meet the needs of biological research and lay the foundation for future therapeutic applications of diseases.


Assuntos
Bases de Dados Genéticas , Doença , RNA , Animais , Mamíferos/genética , Neoplasias/genética , RNA/genética , RNA Longo não Codificante/genética , RNA não Traduzido , Doença/genética
6.
Proc Natl Acad Sci U S A ; 119(46): e2214569119, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36343225

RESUMO

Immunocyte infiltration and cytotoxicity play critical roles in both inflammation and immunotherapy. However, current cancer immunotherapy screening methods overlook the capacity of the T cells to penetrate the tumor stroma, thereby significantly limiting the development of effective treatments for solid tumors. Here, we present an automated high-throughput microfluidic platform for simultaneous tracking of the dynamics of T cell infiltration and cytotoxicity within the 3D tumor cultures with a tunable stromal makeup. By recourse to a clinical tumor-infiltrating lymphocyte (TIL) score analyzer, which is based on a clinical data-driven deep learning method, our platform can evaluate the efficacy of each treatment based on the scoring of T cell infiltration patterns. By screening a drug library using this technology, we identified an epigenetic drug (lysine-specific histone demethylase 1 inhibitor, LSD1i) that effectively promoted T cell tumor infiltration and enhanced treatment efficacy in combination with an immune checkpoint inhibitor (anti-PD1) in vivo. We demonstrated an automated system and strategy for screening immunocyte-solid tumor interactions, enabling the discovery of immuno- and combination therapies.


Assuntos
Aprendizado Profundo , Neoplasias , Humanos , Microfluídica/métodos , Detecção Precoce de Câncer , Imunoterapia/métodos , Linfócitos do Interstício Tumoral , Fatores Imunológicos , Neoplasias/tratamento farmacológico , Microambiente Tumoral
7.
Nano Lett ; 24(29): 8979-8987, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38994924

RESUMO

With the development of miniaturized devices, there is an increasing demand for 2D multifunctional materials. Six ferroelastic semiconductors, Y2Se2XX' (X, X' = I, Br, Cl, or F; X ≠ X') monolayers, are theoretically predicted here. Their in-plane anisotropic band structure, elastic and piezoelectric properties can be switched by ferroelastic strain. Moderate energy barriers can prevent the undesired ferroelastic switching that minor interferences produce. These monolayers exhibit high carrier mobilities (up to 104 cm2 V-1 s-1) with strong in-plane anisotropy. Furthermore, their wide bandgaps and high potential differences make them broad-pH-value and high-performance photocatalysts at pH value of 0-14. Strikingly, Y2Se2BrF possesses outstanding d33 (d33 = -405.97 pm/V), greatly outperforming CuInP2S6 by 4.26 times. Overall, the nano Y2Se2BrF is a hopeful candidate for multifunctional devices to generate a direct current and achieve solar-free photocatalysis. This work provides a new paradigm for the design of multifunctional energy materials.

8.
Nano Lett ; 24(38): 11976-11984, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39270053

RESUMO

Elevated production of extracellular matrix (ECM) in tumor stroma is a critical obstacle for drug penetration. Here we demonstrate that ATP-citrate lyase (ACLY) is significantly upregulated in cancer-associated fibroblasts (CAFs) to produce tumor ECM. Using a self-assembling nanoparticle-design approach, a carrier-free nanoagent (CFNA) is fabricated by simply assembling NDI-091143, a specific ACLY inhibitor, and doxorubicin (DOX) or paclitaxel (PTX), the first-line chemotherapeutic drug, via multiple noncovalent interactions. After arriving at the CAFs-rich tumor site, NDI-091143-mediated ACLY inhibition in CAFs can block the de novo synthesis of fatty acid, thereby dampening the fatty acid-involved energy metabolic process. As the lack of enough energy, the energetic CAFs will be in a dispirited state that is unable to produce abundant ECM, thereby significantly improving drug perfusion in tumors and enhancing the efficacy of chemotherapy. Such a simple drug assembling strategy aimed at CAFs' ACLY-mediated metabolism pathway presents the feasibility of stromal matrix reduction to potentiate chemotherapy.


Assuntos
ATP Citrato (pro-S)-Liase , Fibroblastos Associados a Câncer , Doxorrubicina , Paclitaxel , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Doxorrubicina/farmacologia , Doxorrubicina/química , Humanos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Animais , Camundongos , ATP Citrato (pro-S)-Liase/metabolismo , ATP Citrato (pro-S)-Liase/antagonistas & inibidores , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Microambiente Tumoral/efeitos dos fármacos
9.
Diabetologia ; 67(4): 738-754, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38236410

RESUMO

AIMS/HYPOTHESIS: Sodium-glucose co-transporter 2 (SGLT2) inhibitors (SGLT2i) are antihyperglycaemic drugs that protect the kidneys of individuals with type 2 diabetes mellitus. However, the underlying mechanisms mediating the renal benefits of SGLT2i are not fully understood. Considering the fuel switches that occur during therapeutic SGLT2 inhibition, we hypothesised that SGLT2i induce fasting-like and aestivation-like metabolic patterns, both of which contribute to the regulation of metabolic reprogramming in diabetic kidney disease (DKD). METHODS: Untargeted and targeted metabolomics assays were performed on plasma samples from participants with type 2 diabetes and kidney disease (n=35, 11 women) receiving canagliflozin (CANA) 100 mg/day at baseline and 12 week follow-up. Next, a systematic snapshot of the effect of CANA on key metabolites and pathways in the kidney was obtained using db/db mice. Moreover, the effects of glycine supplementation in db/db mice and human proximal tubular epithelial cells (human kidney-2 [HK-2]) cells were studied. RESULTS: Treatment of DKD patients with CANA for 12 weeks significantly reduced HbA1c from a median (interquartile range 25-75%) of 49.0 (44.0-57.0) mmol/mol (7.9%, [7.10-9.20%]) to 42.2 (39.7-47.7) mmol/mol (6.8%, [6.40-7.70%]), and reduced urinary albumin/creatinine ratio from 67.8 (45.9-159.0) mg/mmol to 47.0 (26.0-93.6) mg/mmol. The untargeted metabolomics assay showed downregulated glycolysis and upregulated fatty acid oxidation. The targeted metabolomics assay revealed significant upregulation of glycine. The kidneys of db/db mice undergo significant metabolic reprogramming, with changes in sugar, lipid and amino acid metabolism; CANA regulated the metabolic reprogramming in the kidneys of db/db mice. In particular, the pathways for glycine, serine and threonine metabolism, as well as the metabolite of glycine, were significantly upregulated in CANA-treated kidneys. Glycine supplementation ameliorated renal lesions in db/db mice by inhibiting food intake, improving insulin sensitivity and reducing blood glucose levels. Glycine supplementation improved apoptosis of human proximal tubule cells via the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway. CONCLUSIONS/INTERPRETATION: In conclusion, our study shows that CANA ameliorates DKD by inducing fasting-like and aestivation-like metabolic patterns. Furthermore, DKD was ameliorated by glycine supplementation, and the beneficial effects of glycine were probably due to the activation of the AMPK/mTOR pathway.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Inibidores do Transportador 2 de Sódio-Glicose , Camundongos , Animais , Humanos , Feminino , Canagliflozina/farmacologia , Canagliflozina/uso terapêutico , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/metabolismo , Reprogramação Metabólica , Proteínas Quinases Ativadas por AMP/metabolismo , Transportador 2 de Glucose-Sódio/metabolismo , Estivação , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/metabolismo , Rim/metabolismo , Jejum , Serina-Treonina Quinases TOR/metabolismo , Glicina/metabolismo , Mamíferos/metabolismo
10.
Hum Mol Genet ; 31(8): 1346-1355, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-34964454

RESUMO

Mitochondrial DNA copy number (mtDNAcn) variation has been associated with increased risk of several human diseases in epidemiological studies. The quantification of mtDNAcn performed with real-time PCR is currently considered the de facto standard among several techniques. However, the heterogeneity of the laboratory methods (DNA extraction, storage, processing) used could give rise to results that are difficult to compare and reproduce across different studies. Several lines of evidence suggest that mtDNAcn is influenced by nuclear and mitochondrial genetic variability, however this relation is largely unexplored. The aim of this work was to elucidate the genetic basis of mtDNAcn variation. We performed a genome-wide association study (GWAS) of mtDNAcn in 6836 subjects from the ESTHER prospective cohort, and included, as replication set, the summary statistics of a GWAS that used 295 150 participants from the UK Biobank. We observed two novel associations with mtDNAcn variation on chromosome 19 (rs117176661), and 12 (rs7136238) that reached statistical significance at the genome-wide level. A polygenic score that we called mitoscore including all known single nucleotide polymorphisms explained 1.11% of the variation of mtDNAcn (p = 5.93 × 10-7). In conclusion, we performed a GWAS on mtDNAcn, adding to the evidence of the genetic background of this trait.


Assuntos
Variações do Número de Cópias de DNA , Estudo de Associação Genômica Ampla , Variações do Número de Cópias de DNA/genética , DNA Mitocondrial/genética , Humanos , Mitocôndrias/genética , Estudos Prospectivos
11.
Mol Med ; 30(1): 71, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38797859

RESUMO

Diabetes mellitus, a chronic metabolic disease, often leads to numerous chronic complications, significantly contributing to global morbidity and mortality rates. High glucose levels trigger epigenetic modifications linked to pathophysiological processes like inflammation, immunity, oxidative stress, mitochondrial dysfunction, senescence and various kinds of cell death. Despite glycemic control, transient hyperglycemia can persistently harm organs, tissues, and cells, a latent effect termed "metabolic memory" that contributes to chronic diabetic complications. Understanding metabolic memory's mechanisms could offer a new approach to mitigating these complications. However, key molecules and networks underlying metabolic memory remain incompletely understood. This review traces the history of metabolic memory research, highlights its key features, discusses recent molecules involved in its mechanisms, and summarizes confirmed and potential therapeutic compounds. Additionally, we outline in vitro and in vivo models of metabolic memory. We hope this work will inform future research on metabolic memory's regulatory mechanisms and facilitate the development of effective therapeutic compounds to prevent diabetic complications.


Assuntos
Complicações do Diabetes , Humanos , Animais , Complicações do Diabetes/metabolismo , Diabetes Mellitus/metabolismo , Diabetes Mellitus/etiologia , Epigênese Genética , Estresse Oxidativo , Hiperglicemia/metabolismo
12.
Eur Respir J ; 63(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38514093

RESUMO

RATIONALE: Respiratory virus-induced inflammation is the leading cause of asthma exacerbation, frequently accompanied by induction of interferon-stimulated genes (ISGs). How asthma-susceptibility genes modulate cellular response upon viral infection by fine-tuning ISG induction and subsequent airway inflammation in genetically susceptible asthma patients remains largely unknown. OBJECTIVES: To decipher the functions of gasdermin B (encoded by GSDMB) in respiratory virus-induced lung inflammation. METHODS: In two independent cohorts, we analysed expression correlation between GSDMB and ISG s. In human bronchial epithelial cell line or primary bronchial epithelial cells, we generated GSDMB-overexpressing and GSDMB-deficient cells. A series of quantitative PCR, ELISA and co-immunoprecipitation assays were performed to determine the function and mechanism of GSDMB for ISG induction. We also generated a novel transgenic mouse line with inducible expression of human unique GSDMB gene in airway epithelial cells and infected the mice with respiratory syncytial virus to determine the role of GSDMB in respiratory syncytial virus-induced lung inflammation in vivo. RESULTS: GSDMB is one of the most significant asthma-susceptibility genes at 17q21 and acts as a novel RNA sensor, promoting mitochondrial antiviral-signalling protein (MAVS)-TANK binding kinase 1 (TBK1) signalling and subsequent inflammation. In airway epithelium, GSDMB is induced by respiratory viral infections. Expression of GSDMB and ISGs significantly correlated in respiratory epithelium from two independent asthma cohorts. Notably, inducible expression of human GSDMB in mouse airway epithelium led to enhanced ISGs induction and increased airway inflammation with mucus hypersecretion upon respiratory syncytial virus infection. CONCLUSIONS: GSDMB promotes ISGs expression and airway inflammation upon respiratory virus infection, thereby conferring asthma risk in risk allele carriers.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Asma , Gasderminas , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Animais , Humanos , Asma/metabolismo , Asma/genética , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Camundongos Transgênicos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Predisposição Genética para Doença , Infecções por Vírus Respiratório Sincicial/metabolismo , Infecções por Vírus Respiratório Sincicial/genética , Células Epiteliais/metabolismo , Linhagem Celular , Brônquios/metabolismo , Brônquios/patologia , Pneumonia/metabolismo , Pneumonia/genética , Pneumonia/virologia , Feminino , Pulmão/metabolismo , Pulmão/patologia
13.
Small ; 20(12): e2307685, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37946630

RESUMO

The rational design of metal-organic framework (MOF)-based electrocatalysts plays a key role in achieving high-efficiency oxygen evolution reaction (OER). Herein, a synergetic morphology and electronic structure engineering strategy are proposed to design a Co-MOF nanoflower grown on carbon paper via rare-earth cerium doping (CoCe-MOF/CP). Compared with Co-MOF/CP, the developed CoCe-MOF/CP exhibited superior OER performance with a low overpotential of 267 mV at 10 mA cm-2 and outstanding long-term stability over 100 h. Theoretical calculations show that the unique 4f valence electron structure of Ce induced charge redistribution of the Co-MOF surface through the strong Co 3d-O 2p-Ce 4f orbital electronic coupling below the Fermi level. Ce-doped plays a key role in the engineering of the electronic states of the Co sites to endow them with the optimal free energy landscape for enhanced OER catalytic activity. This work provides new insights into comprehending the RE-enhanced mechanism of electrocatalysis and provides an effective strategy for the design of MOF-based electrocatalysts.

14.
Small ; 20(35): e2401566, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38752437

RESUMO

Ultrathin carbon nitride pioneered a paradigm that facilitates effective charge separation and acceleration of rapid charge migration. Nevertheless, the dissociation process confronts a disruption owing to the proclivity of carbon nitride to reaggregate, thereby impeding the optimal utilization of active sites. In response to this exigency, the adoption of a synthesis methodology featuring alkaline potassium salt-assisted molten salt synthesis is advocated in this work, aiming to craft a nitrogenated graphitic carbon nitride (g-C3N5) photocatalyst characterized by thin layer and hydrophilicity, which not only amplifies the degree of crystallization of g-C3N5 but also introduces a plethora of abundant edge active sites, engendering a quasi-homogeneous photocatalytic system. Under visible light irradiation, the ultra-high H2O2 production rate of this modified high-crystalline g-C3N5 in pure water attains 151.14 µm h-1. This groundbreaking study offers a novel perspective for the innovative design of highly efficient photocatalysts with a quasi-homogeneous photocatalytic system.

15.
Appl Environ Microbiol ; 90(2): e0201623, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38214515

RESUMO

Global warming has led to a high incidence of extreme heat events, and the frequent occurrence of extreme heat events has had extensive and far-reaching impacts on wetland ecosystems. The widespread distribution of plastics in the environment, including polyethylene (PE), polylactic acid (PLA), and tire particles (TPs), has caused various environmental problems. Here, high-throughput sequencing techniques and metabolomics were used for the first time to investigate the effects of three popular microplastic types: PE, PLA, and TP, on the sediment microbiome and the metabolome at both temperatures. The microplastics were incorporated into the sediment at a concentration of 3% by weight of the dry sediment (wt/wt), to reflect environmentally relevant conditions. Sediment enzymatic activity and physicochemical properties were co-regulated by both temperatures and microplastics producing significant differences compared to controls. PE and PLA particles inhibited bacterial diversity at low temperatures and promoted bacterial diversity at high temperatures, and TP particles promoted both at both temperatures. For bacterial richness, only PLA showed inhibition at low temperature; all other treatments showed promotion. PE, PLA, and TP microplastics changed the community structure of sediment bacteria, forming two clusters at low and high temperatures. Furthermore, PE, PLA, and TP changed the sediment metabolic profiles, producing differential metabolites such as lipids and molecules, organic heterocyclic compounds, and organic acids and their derivatives, especially TP had the most significant effect. These findings contribute to a more comprehensive understanding of the potential impact of microplastic contamination.IMPORTANCEIn this study, we added 3% (wt/wt) microplastic particles, including polyethylene, polylactic acid, and tire particles, to natural sediments under simulated laboratory conditions. Subsequently, we simulated the sediment microbial and ecosystem responses under different temperature conditions by incubating them for 60 days at 15°C and 35°C, respectively. After synthesizing these results, our study strongly suggests that the presence of microplastics in sediment ecosystems and exposure under different temperature conditions may have profound effects on soil microbial communities, enzyme activities, and metabolite profiles. This is important for understanding the potential hazards of microplastic contamination on terrestrial ecosystems and for developing relevant environmental management strategies.


Assuntos
Microbiota , Poluentes Químicos da Água , Plásticos , Microplásticos/química , Microplásticos/farmacologia , Polietileno/análise , Polietileno/farmacologia , Ecossistema , Temperatura , Poluentes Químicos da Água/análise , Sedimentos Geológicos/microbiologia , Poliésteres , Metaboloma , Monitoramento Ambiental
16.
New Phytol ; 243(4): 1329-1346, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38898642

RESUMO

Drought-induced xylem embolism is a primary cause of plant mortality. Although c. 70% of cycads are threatened by extinction and extant cycads diversified during a period of increasing aridification, the vulnerability of cycads to embolism spread has been overlooked. We quantified the vulnerability to drought-induced embolism, pressure-volume curves, in situ water potentials, and a suite of xylem anatomical traits of leaf pinnae and rachises for 20 cycad species. We tested whether anatomical traits were linked to hydraulic safety in cycads. Compared with other major vascular plant clades, cycads exhibited similar embolism resistance to angiosperms and pteridophytes but were more vulnerable to embolism than noncycad gymnosperms. All 20 cycads had both tracheids and vessels, the proportions of which were unrelated to embolism resistance. Only vessel pit membrane fraction was positively correlated to embolism resistance, contrary to angiosperms. Water potential at turgor loss was significantly correlated to embolism resistance among cycads. Our results show that cycads exhibit low resistance to xylem embolism and that xylem anatomical traits - particularly vessels - may influence embolism resistance together with tracheids. This study highlights the importance of understanding the mechanisms of drought resistance in evolutionarily unique and threatened lineages like the cycads.


Assuntos
Cycadopsida , Secas , Folhas de Planta , Água , Xilema , Xilema/fisiologia , Xilema/anatomia & histologia , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Cycadopsida/fisiologia , Cycadopsida/anatomia & histologia , Especificidade da Espécie
17.
Opt Express ; 32(2): 2271-2280, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297761

RESUMO

In this article, we report a Si/Ge waveguide phototransistor with high responsivity and low dark current under low bias voltages, due to an engineered electric field distribution. The photodetector consists of n-i-p-i-n doping regions and shows a responsivity of 606 A/W at 1 V bias, and 1032 A/W at 2.8V bias with an input optical power of -50 dBm, and dark current of 4 µA and 42 µA respectively. This is achieved by placing two p+-doped regions in the silicon slab region beneath the Ge epitaxial layer. A measured small signal -3 dB bandwidth of 1.5 GHz with a -80 dBc/Hz phase noise response at 1 KHz frequency offset were demonstrated experimentally.

18.
Crit Rev Biotechnol ; : 1-17, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503543

RESUMO

As an important cell factory, industrial yeast has been widely used for the production of compounds ranging from bulk chemicals to complex natural products. However, various adverse conditions including toxic products, extreme pH, and hyperosmosis etc., severely restrict microbial growth and metabolic performance, limiting the fermentation efficiency and diminishing its competitiveness. Therefore, enhancing the tolerance and robustness of yeasts is critical to ensure reliable and sustainable production of metabolites in complex industrial production processes. In this review, we provide a comprehensive review of various strategies for improving the tolerance of yeast cells, including random mutagenesis, system metabolic engineering, and material-mediated immobilization cell technology. It is expected that this review will provide a new perspective to realize the response and intelligent regulation of yeast cells to environmental stresses.

19.
FASEB J ; 37(6): e22938, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37130011

RESUMO

Diabetic kidney disease (DKD) develops in ~40% of patients with diabetes and is the leading cause of chronic kidney disease worldwide. We used single-cell RNA-sequencing and spatial transcriptomic analyses of kidney specimens from patients with DKD. Unsupervised clustering revealed distinct cell clusters, including epithelial cells and fibroblasts. We also identified differentially expressed genes (DEGs) and assessed enrichment, and cell-cell interactions. Specific enrichment of DKD was evident in venous endothelial cells (VECs) and fibroblasts with elevated CCL19 expression. The DEGs in most kidney parenchymal cells in DKD were primarily enriched in inflammatory signaling pathways. Intercellular crosstalk revealed that most cell interactions in DKD are associated with chemokines. Spatial transcriptomics revealed that VECs co-localized with fibroblasts, with most immune cells being enriched in areas of renal fibrosis. These results provided insight into the cell populations, intercellular interactions, and signaling pathways underlying the pathogenesis and potential targets for treating DKD.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Humanos , Nefropatias Diabéticas/metabolismo , Células Endoteliais/metabolismo , Transcriptoma , Análise da Expressão Gênica de Célula Única , Rim/metabolismo , Diabetes Mellitus/metabolismo
20.
Gastrointest Endosc ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38692516

RESUMO

BACKGROUND AND AIMS: Lymph node metastasis significantly affects the prognosis of early gastric cancer patients. EUS plays a crucial role in the preoperative assessment of early gastric cancer. This study evaluated the efficacy of EUS in identifying lymph node metastasis in early gastric cancer patients and developed a risk score model to aid in choosing the best treatment options. METHODS: We retrospectively analyzed the effectiveness of EUS for detecting lymph node metastasis in early gastric cancer patients. A risk score model for predicting lymph node metastasis preoperatively was created using independent risk factors identified through binary logistic regression analysis and subsequently validated. Receiver operating characteristic curves were generated for both the development and validation cohorts. RESULTS: The overall accuracy of EUS in identifying lymph node metastasis was 85.3%, although its sensitivity (29.2%) and positive predictive value (38.7%) were relatively low. Patients were categorized based on preoperative risk factors for lymph node metastasis, including tumor size of ≥20 mm, lymph nodes of ≥10 mm, body mass index of ≥24 kg/m2, and lymph node metastasis on CT scans. A 7-point risk score model was developed to assess the likelihood of lymph node metastasis. The areas under the receiver operating characteristic curve for the development and validation sets were 0.842 and 0.837, respectively, with sensitivities of 64% and 79%, respectively. CONCLUSIONS: We developed a practical risk score model based on preoperative factors to help EUS predict lymph node metastasis in early gastric cancer patients, guiding the selection of optimal treatment approaches for these patients.

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