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1.
Cell ; 187(18): 4890-4904.e9, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39013470

RESUMO

Allogeneic chimeric antigen receptor (CAR)-T cells hold great promise for expanding the accessibility of CAR-T therapy, whereas the risks of allograft rejection have hampered its application. Here, we genetically engineered healthy-donor-derived, CD19-targeting CAR-T cells using CRISPR-Cas9 to address the issue of immune rejection and treated one patient with refractory immune-mediated necrotizing myopathy and two patients with diffuse cutaneous systemic sclerosis with these cells. This study was registered at ClinicalTrials.gov (NCT05859997). The infused cells persisted for over 3 months, achieving complete B cell depletion within 2 weeks of treatment. During the 6-month follow-up, we observed deep remission without cytokine release syndrome or other serious adverse events in all three patients, primarily shown by the significant improvement in the clinical response index scores for the two diseases, respectively, and supported by the observations of reversal of inflammation and fibrosis. Our results demonstrate the high safety and promising immune modulatory effect of the off-the-shelf CAR-T cells in treating severe refractory autoimmune diseases.


Assuntos
Antígenos CD19 , Imunoterapia Adotiva , Miosite , Receptores de Antígenos Quiméricos , Escleroderma Sistêmico , Humanos , Antígenos CD19/imunologia , Antígenos CD19/metabolismo , Miosite/terapia , Miosite/imunologia , Escleroderma Sistêmico/terapia , Escleroderma Sistêmico/imunologia , Imunoterapia Adotiva/métodos , Feminino , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Masculino , Pessoa de Meia-Idade , Adulto , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transplante Homólogo
2.
Cell ; 167(2): 397-404.e9, 2016 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-27667683

RESUMO

Antibody blockade of the inhibitory CTLA-4 pathway has led to clinical benefit in a subset of patients with metastatic melanoma. Anti-CTLA-4 enhances T cell responses, including production of IFN-γ, which is a critical cytokine for host immune responses. However, the role of IFN-γ signaling in tumor cells in the setting of anti-CTLA-4 therapy remains unknown. Here, we demonstrate that patients identified as non-responders to anti-CTLA-4 (ipilimumab) have tumors with genomic defects in IFN-γ pathway genes. Furthermore, mice bearing melanoma tumors with knockdown of IFN-γ receptor 1 (IFNGR1) have impaired tumor rejection upon anti-CTLA-4 therapy. These data highlight that loss of the IFN-γ signaling pathway is associated with primary resistance to anti-CTLA-4 therapy. Our findings demonstrate the importance of tumor genomic data, especially IFN-γ related genes, as prognostic information for patients selected to receive treatment with immune checkpoint therapy.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígeno CTLA-4/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/genética , Interferon gama/genética , Melanoma/tratamento farmacológico , Receptores de Interferon/genética , Neoplasias Cutâneas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Citocinas/imunologia , Técnicas de Silenciamento de Genes , Humanos , Ipilimumab , Melanoma/genética , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/genética , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Cutâneas/genética , Linfócitos T/imunologia , Receptor de Interferon gama
3.
Nature ; 621(7977): 75-81, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37673990

RESUMO

Benefiting from high energy density (2,600 Wh kg-1) and low cost, lithium-sulfur (Li-S) batteries are considered promising candidates for advanced energy-storage systems1-4. Despite tremendous efforts in suppressing the long-standing shuttle effect of lithium polysulfides5-7, understanding of the interfacial reactions of lithium polysulfides at the nanoscale remains elusive. This is mainly because of the limitations of in situ characterization tools in tracing the liquid-solid conversion of unstable lithium polysulfides at high temporal-spatial resolution8-10. There is an urgent need to understand the coupled phenomena inside Li-S batteries, specifically, the dynamic distribution, aggregation, deposition and dissolution of lithium polysulfides. Here, by using in situ liquid-cell electrochemical transmission electron microscopy, we directly visualized the transformation of lithium polysulfides over electrode surfaces at the atomic scale. Notably, an unexpected gathering-induced collective charge transfer of lithium polysulfides was captured on the nanocluster active-centre-immobilized surface. It further induced an instantaneous deposition of nonequilibrium Li2S nanocrystals from the dense liquid phase of lithium polysulfides. Without mediation of active centres, the reactions followed a classical single-molecule pathway, lithium polysulfides transforming into Li2S2 and Li2S step by step. Molecular dynamics simulations indicated that the long-range electrostatic interaction between active centres and lithium polysulfides promoted the formation of a dense phase consisting of Li+ and Sn2- (2 < n ≤ 6), and the collective charge transfer in the dense phase was further verified by ab initio molecular dynamics simulations. The collective interfacial reaction pathway unveils a new transformation mechanism and deepens the fundamental understanding of Li-S batteries.

4.
Immunity ; 50(1): 137-151.e6, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30650373

RESUMO

Fever is an evolutionarily conserved response that confers survival benefits during infection. However, the underlying mechanism remains obscure. Here, we report that fever promoted T lymphocyte trafficking through heat shock protein 90 (Hsp90)-induced α4 integrin activation and signaling in T cells. By inducing selective binding of Hsp90 to α4 integrins, but not ß2 integrins, fever increased α4-integrin-mediated T cell adhesion and transmigration. Mechanistically, Hsp90 bound to the α4 tail and activated α4 integrins via inside-out signaling. Moreover, the N and C termini of one Hsp90 molecule simultaneously bound to two α4 tails, leading to dimerization and clustering of α4 integrins on the cell membrane and subsequent activation of the FAK-RhoA pathway. Abolishment of Hsp90-α4 interaction inhibited fever-induced T cell trafficking to draining lymph nodes and impaired the clearance of bacterial infection. Our findings identify the Hsp90-α4-integrin axis as a thermal sensory pathway that promotes T lymphocyte trafficking and enhances immune surveillance during infection.


Assuntos
Febre/imunologia , Proteínas de Choque Térmico HSP90/metabolismo , Integrina alfa4/metabolismo , Infecções por Salmonella/imunologia , Salmonella typhimurium/imunologia , Linfócitos T/imunologia , Animais , Carga Bacteriana , Adesão Celular , Movimento Celular , Dimerização , Quinase 1 de Adesão Focal/metabolismo , Vigilância Imunológica , Integrina alfa4/genética , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ligação Proteica , Transdução de Sinais , Proteína rhoA de Ligação ao GTP/metabolismo
5.
Proc Natl Acad Sci U S A ; 121(38): e2412031121, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39254999

RESUMO

Higher-order topological phases in non-Hermitian photonics revolutionize the understanding of wave propagation and modulation, which lead to hierarchical states in open systems. However, intrinsic insulating properties endorsed by the lattice symmetry of photonic crystals fundamentally confine the robust transport only at explicit system boundaries, letting alone the flexible reconfiguration in hierarchical states at arbitrary positions. Here, we report a dynamic topological platform for creating the reconfigurable hierarchical bound states in heat transport systems and observe the robust and nonlocalized higher-order states in both the real- and imaginary-valued bands. Our experiments showcase that the hierarchical features of zero-dimension corner and nontrivial edge modes occur at tailored positions within the system bulk states instead of the explicit system boundaries. Our findings uncover the mechanism of non-localized hierarchical non-trivial topological states and offer distinct paradigms for diffusive transport field management.

6.
Proc Natl Acad Sci U S A ; 121(35): e2408843121, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39163329

RESUMO

The topological physics has sparked intensive investigations into topological lattices in photonic, acoustic, and mechanical systems, powering counterintuitive effects otherwise inaccessible with usual settings. Following the success of these endeavors in classical wave dynamics, there has been a growing interest in establishing their topological counterparts in diffusion. Here, we propose an additional real-space dimension in diffusion, and the system eigenvalues are transformed from "imaginary" to "real." By judiciously tailoring the effective Hamiltonian with coupling networks, localized and delocalized topological modes are realized in heat transfer. Simulations and experiments in active thermal lattices validate the effectiveness of the proposed theoretical strategy. This approach can be applied to establish various topological lattices in diffusion systems, offering insights into engineering topologically protected edge states in dynamic diffusive scenarios.

7.
Proc Natl Acad Sci U S A ; 121(6): e2304619121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38289962

RESUMO

Resistance to neoadjuvant chemotherapy leads to poor prognosis of locally advanced rectal cancer (LARC), representing an unmet clinical need that demands further exploration of therapeutic strategies to improve clinical outcomes. Here, we identified a noncanonical role of RB1 for modulating chromatin activity that contributes to oxaliplatin resistance in colorectal cancer (CRC). We demonstrate that oxaliplatin induces RB1 phosphorylation, which is associated with the resistance to neoadjuvant oxaliplatin-based chemotherapy in LARC. Inhibition of RB1 phosphorylation by CDK4/6 inhibitor results in vulnerability to oxaliplatin in both intrinsic and acquired chemoresistant CRC. Mechanistically, we show that RB1 modulates chromatin activity through the TEAD4/HDAC1 complex to epigenetically suppress the expression of DNA repair genes. Antagonizing RB1 phosphorylation through CDK4/6 inhibition enforces RB1/TEAD4/HDAC1 repressor activity, leading to DNA repair defects, thus sensitizing oxaliplatin treatment in LARC. Our study identifies a RB1 function in regulating chromatin activity through TEAD4/HDAC1. It also provides the combination of CDK4/6 inhibitor with oxaliplatin as a potential synthetic lethality strategy to mitigate oxaliplatin resistance in LARC, whereby phosphorylated RB1/TEAD4 can serve as potential biomarkers to guide the patient stratification.


Assuntos
Terapia Neoadjuvante , Neoplasias Retais , Humanos , Oxaliplatina/farmacologia , Terapia Neoadjuvante/métodos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/genética , Quimiorradioterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cromatina , Resultado do Tratamento , Fatores de Transcrição de Domínio TEA , Ubiquitina-Proteína Ligases , Proteínas de Ligação a Retinoblastoma
8.
Nucleic Acids Res ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39228373

RESUMO

As a potent and convenient genome-editing tool, Cas9 has been widely used in biomedical research and evaluated in treating human diseases. Numerous engineered variants of Cas9, dCas9 and other related prokaryotic endonucleases have been identified. However, as these bacterial enzymes are not naturally present in mammalian cells, whether and how bacterial Cas9 proteins are recognized and regulated by mammalian hosts remain poorly understood. Here, we identify Keap1 as a mammalian endogenous E3 ligase that targets Cas9/dCas9/Fanzor for ubiquitination and degradation in an 'ETGE'-like degron-dependent manner. Cas9-'ETGE'-like degron mutants evading Keap1 recognition display enhanced gene editing ability in cells. dCas9-'ETGE'-like degron mutants exert extended protein half-life and protein retention on chromatin, leading to improved CRISPRa and CRISPRi efficacy. Moreover, Cas9 binding to Keap1 also impairs Keap1 function by competing with Keap1 substrates or binding partners for Keap1 binding, while engineered Cas9 mutants show less perturbation of Keap1 biology. Thus, our study reveals a mammalian specific Cas9 regulation and provides new Cas9 designs not only with enhanced gene regulatory capacity but also with minimal effects on disrupting endogenous Keap1 signaling.

9.
Eur Heart J ; 45(37): 3853-3867, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39165142

RESUMO

BACKGROUND AND AIMS: Heart failure (HF) is a leading cause of mortality worldwide and characterized by significant co-morbidities and dismal prognosis. Neutrophil extracellular traps (NETs) aggravate inflammation in various cardiovascular diseases; however, their function and mechanism of action in HF pathogenesis remain underexplored. This study aimed to investigate the involvement of a novel VWF-SLC44A2-NET axis in HF progression. METHODS: NET levels were examined in patients with HF and mouse models of transverse aortic constriction (TAC) HF. PAD4 knockout mice and NET inhibitors (GSK-484, DNase I, NEi) were used to evaluate the role of NETs in HF. RNA sequencing was used to investigate the downstream mechanisms. Recombinant human ADAMTS13 (rhADAMTS13), ADAMTS13, and SLC44A2 knockouts were used to identify novel upstream factors of NETs. RESULTS: Elevated NET levels were observed in patients with HF and TAC mouse models of HF. PAD4 knockout and NET inhibitors improved the cardiac function. Mechanistically, NETs induced mitochondrial dysfunction in cardiomyocytes, inhibiting mitochondrial biogenesis via the NE-TLR4-mediated suppression of PGC-1α. Furthermore, VWF/ADAMTS13 regulated NET formation via SLC44A2. Additionally, sacubitril/valsartan amplifies the cardioprotective effects of the VWF-SLC44A2-NET axis blockade. CONCLUSIONS: This study established the role of a novel VWF-SLC44A2-NET axis in regulating mitochondrial homeostasis and function, leading to cardiac apoptosis and contributing to HF pathogenesis. Targeting this axis may offer a potential therapeutic approach for HF treatment.


Assuntos
Modelos Animais de Doenças , Armadilhas Extracelulares , Insuficiência Cardíaca , Fator de von Willebrand , Animais , Humanos , Masculino , Camundongos , Proteína ADAMTS13/metabolismo , Proteína ADAMTS13/genética , Armadilhas Extracelulares/metabolismo , Insuficiência Cardíaca/metabolismo , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Neutrófilos/metabolismo , Proteína-Arginina Desiminase do Tipo 4/metabolismo , Valsartana/farmacologia , Fator de von Willebrand/metabolismo
10.
Am J Physiol Cell Physiol ; 326(1): C206-C213, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38047298

RESUMO

People with primary focal hyperhidrosis (PFH) usually have an overactive sympathetic nervous system, which can activate the sweat glands through the chemical messenger of acetylcholine. The role of aquaporin 5 (AQP5) and Na-K-2Cl cotransporter 1 (NKCC1) in PFH is still unknown. The relative mRNA and protein levels of AQP5 and NKCC1 in the sweat gland tissues of three subtypes of patients with PFH (primary palmar hyperhidrosis, PPH; primary axillary hyperhidrosis, PAH; and primary craniofacial hyperhidrosis, PCH) were detected with real-time PCR (qPCR) and Western blot. Primary sweat gland cells from healthy controls (NPFH-SG) were incubated with different concentrations of acetylcholine, and the relative mRNA and protein expression of AQP5 and NKCC1 were also detected. NPFH-SG cells were also transfected with si-AQP5 or shNKCC1, and acetylcholine stimulation-induced calcium transients were assayed with Fluo-3 AM calcium assay. Upregulated AQP5 and NKCC1 expression were observed in sweat gland tissues, and AQP5 demonstrated a positive Pearson correlation with NKCC1 in patients with PPH (r = 0.66, P < 0.001), patients with PAH (r = 0.71, P < 0.001), and patients with PCH (r = 0.62, P < 0.001). Upregulated AQP5 and NKCC1 expression were also detected in primary sweat gland cells derived from three subtypes of patients with PFH when compared with primary sweat gland cells derived from healthy control. Acetylcholine stimulation could induce the upregulated AQP5 and NKCC1 expression in NPFH-SG cells, and AQP5 or NKCC1 inhibitions attenuated the calcium transients induced by acetylcholine stimulation in NPFH-SG cells. The dependence of ACh-stimulated calcium transients on AQP5 and NKCC1 expression may be involved in the development of PFH.NEW & NOTEWORTHY The dependence of ACh-stimulated calcium transients on AQP5 and Na-K-2Cl cotransporter 1 (NKCC1) expression may be involved in the development of primary focal hyperhidrosis (PFH).


Assuntos
Aquaporina 5 , Hiperidrose , Humanos , Acetilcolina/farmacologia , Acetilcolina/metabolismo , Aquaporina 5/genética , Aquaporina 5/metabolismo , Cálcio/metabolismo , Técnicas de Cultura de Células , Hiperidrose/metabolismo , RNA Mensageiro/metabolismo , Glândulas Sudoríparas/química , Glândulas Sudoríparas/metabolismo
11.
Biochem Biophys Res Commun ; 711: 149894, 2024 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-38603834

RESUMO

BACKGROUND: Low-grade glioma (LGG) has an extremely poor prognosis, and the mechanism leading to malignant development has not been determined. The aim of our study was to clarify the function and mechanism of anoikis and TIMP1 in the malignant progression of LGG. METHODS: We screened 7 anoikis-related genes from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases to construct a prognostic-predicting model. The study assessed the clinical prognosis, pathological characteristics, and immune cell infiltration in both high- and low-risk groups. Additionally, the potential modulatory effects of TIMP1 on proliferation, migration, and anoikis in LGG were investigated both in vivo and in vitro. RESULTS: In this study, we identified seven critical genes, namely, PTGS2, CCND1, TIMP1, PDK4, LGALS3, CDKN1A, and CDKN2A. Kaplan‒Meier (K‒M) curves demonstrated a significant correlation between clinical features and overall survival (OS), and single-cell analysis and mutation examination emphasized the heterogeneity and pivotal role of hub gene expression imbalances in LGG development. Immune cell infiltration and microenvironment analysis further elucidated the relationships between key genes and immune cells. In addition, TIMP1 promoted the malignant progression of LGG in both in vitro and in vivo models. CONCLUSIONS: This study confirmed that TIMP1 promoted the malignant progression of LGG by inhibiting anoikis, providing insights into LGG pathogenesis and potential therapeutic targets.


Assuntos
Anoikis , Glioma , Inibidor Tecidual de Metaloproteinase-1 , Humanos , Anoikis/genética , Glioma/genética , Glioma/imunologia , Glioma/patologia , Prognóstico , Inibidor Tecidual de Metaloproteinase-1/genética , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/mortalidade , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Camundongos , Masculino , Proliferação de Células/genética , Feminino , Camundongos Nus , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Gradação de Tumores
12.
Small ; 20(11): e2305889, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939307

RESUMO

The development of highly active and acid-stable electrocatalysts for oxygen evolution reaction (OER) is of great significance for water electrolysis technology. Herein, a highly efficient molybdenum-doped mesoporous ruthenium dioxide sphere (Mo-RuO2 ) catalyst is fabricated by a facile impregnation and post-calcination method using mesoporous carbon spheres to template the mesostructure. The optimal Mo0.15 -RuO2 catalyst with Mo doping amount of 15 mol.% exhibits a significantly low overpotential of 147 mV at 10 mA cm-2 , a small Tafel slope of 38 mV decade-1 , and enhanced electrochemical stability in acidic electrolyte, far superior to the commercial RuO2 catalyst. The experimental results and theoretical analysis reveal that the remarkable electrocatalytic performance can be attributed to the large surface area of the mesoporous spherical structure, the structural robustness of the interconnected mesoporous framework, and the change in the electronic structure of Ru active sites induced by Mo doping. These excellent advantages make Mo-doped mesoporous RuO2 spheres a promising catalyst for highly efficient electrocatalytic OER in acidic media.

13.
Small ; 20(17): e2307283, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38109154

RESUMO

Platinum (Pt)-based alloys have received considerable attention due to their compositional variability and unique electrochemical properties. However, homogeneous element distribution at the nanoscale, which is beneficial to various electrocatalytic reactions, is still a great challenge. Herein, a universal approach is proposed to synthesize homogeneously alloyed and size-tunable Pt-based nanoflowers utilizing high gravity technology. Owing to the significant intensification of micro-mixing and mass transfer in unique high gravity shearing surroundings, five typical binary/ternary Pt-based nanoflowers are instantaneously achieved at room temperature. As a proof-of-concept, as-synthesized Platinum-Silver nanoflowers (PtAg NFs) demonstrate excellent catalytic performance and anti-CO poisoning ability for anodic methanol oxidation reaction with high mass activity of 1830 mA mgPt -1, 3.5 and 3.2 times higher than those of conventional beaker products and commercial Pt/C, respectively. The experiment in combination with theory calculations suggest that the enhanced performance is due to additional electronic transmission and optimized d-band center of Pt caused by high alloying degree.

14.
J Transl Med ; 22(1): 865, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39334185

RESUMO

BACKGROUND: The increasing incidence of diabetes mellitus has established diabetic cataracts (DC) as a significant worldwide public health issue. The mechanisms underlying DC remain unknown, and effective prevention and treatment strategies are lacking. Accordingly, we aimed to explore the role and mechanism behind N6-methyladenosine (m6A) in DC progression. METHODS: Methyltransferase-like 3 (METTL3), p21, Beclin1, LC3, and p62 expression levels were measured in human tissues. This study assessed total m6A levels and common m6A-regulated biomarkers in both in vitro and in vivo DC models. Autophagy flux was detected in vitro through Ad-mCherry-GFP-LC3B and Monodansylcadaverine (MDC) staining. Cellular senescence was assessed utilizing the senescence-associated ß-galactosidase (SA-ß-Gal) assay. Furthermore, the effect of METTL3 on SIRT1 mRNA modification was demonstrated, and its mechanism was elucidated using RT-qPCR, western blot, RNA stability assays, and RIP analysis. RESULTS: METTL3, p21, and p62 expression levels were elevated in lens epithelial cells (LECs) from DC patients, while Beclin1 and LC3 levels were reduced. Silencing METTL3-mediated m6A modifications restored high-glucose-induced autophagy inhibition and prevented premature senescence in LECs. Notably, SIRT1720 and Metformin significantly enhanced autophagosome generation and delayed cellular senescence. The m6A-reading protein YTHDF2 bound to m6A modifications, and YTHDF2 silencing significantly reduced METTL3-mediated SIRT1 inactivation. CONCLUSIONS: METTL3 induces senescence in DC by destabilizing SIRT1 mRNA in an m6A-YTHDF2-dependent manner. The METTL3-YTHDF2-SIRT1 axis is a key target and potential pathogenic mechanism in DC.


Assuntos
Adenosina , Autofagia , Catarata , Senescência Celular , Progressão da Doença , Metiltransferases , RNA Mensageiro , Sirtuína 1 , Humanos , Metiltransferases/metabolismo , Metiltransferases/genética , Catarata/genética , Catarata/patologia , Catarata/metabolismo , Autofagia/genética , Sirtuína 1/metabolismo , Sirtuína 1/genética , RNA Mensageiro/metabolismo , RNA Mensageiro/genética , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Masculino , Complicações do Diabetes/metabolismo , Complicações do Diabetes/genética , Complicações do Diabetes/patologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Cristalino/metabolismo , Cristalino/patologia , Feminino , Camundongos , Pessoa de Meia-Idade
15.
Mol Ecol ; : e17528, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283304

RESUMO

Eutrophication reduces the variability of the community composition of plankton. However, the mechanisms underlying the diversity and restructuring of eukaryotic algal communities remain unknown. This study analysed the diversity and compositional patterns of algal communities in shallow eutrophic lakes. It investigated how these communities were modified by key genera through mediating inter-algal associations under the influence of abiotic factors. Inter-algal associations explained more variance in algal communities than environmental variables, and variation in composition and diversity was primarily derived from Scenedesmus, Desmodesmus and Cryptomonas, rather than nutrients. Scenedesmus and Desmodesmus were positively correlated with the genera of Chlorophyta and formed the hub of the algal association network. When the relative abundance of Scenedesmus and Desmodesmus increased from 0.41% to 13.74%, communities enriched in biomarkers of Bacillariophyta, Chrysophyceae and Cryptophyta transitioned to communities enriched in biomarkers of Chlorophyta. Moreover, negative associations between the Chlorophyta hub genera and other non-Chlorophyta genera increased. High concentrations of total phosphorus altered the composition of algal communities by increasing the abundance of Scenedesmus and Desmodesmus, which in turn had cascading effects through inter-algal associations. Additionally, algal communities with higher abundances of Scenedesmus and Desmodesmus were more susceptible to the effects of total phosphorus. Our study suggested that inter-algal associations, centred on Scenedesmus and Desmodesmus, had a greater influence on algal diversity and community structure than other factors. Nutrient levels were not a direct driver of algal diversity and community structure adjustments, but acted indirectly by enhancing the influence of Scenedesmus and Desmodesmus.

16.
Opt Express ; 32(12): 21102-21120, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859473

RESUMO

This study investigates the macroscopic and optical properties of cirrus clouds in the 32N region from July 2016 to May 2017, leveraging data from ground-based lidar observations and CALIOP to overcome the inconsistencies in detected cirrus cloud samples. Through extensive data analysis, statistical characteristics of cirrus clouds were discerned, revealing lidar ratio values of 28.5 ± 10.8 from ground-based lidar and 27.4 ± 11.2 from CALIOP. Validation with a decade of CALIOP data (2008-2018) confirmed these findings, presenting a consistent lidar ratio of 27.4 ± 12.0. A significant outcome of the analysis was the identification of a positive correlation between the lidar ratio and cloud centroid temperature, indicating a gradual decrease in the lidar ratio as temperatures dropped. The study established a fundamental consistency in their macroscopic properties, including cloud base height, cloud top height, cloud thickness, cloud centroid height, and cloud centroid temperature. The results for ground-based lidar (CALIOP) are: 10.0 ± 2.1 km (10.0 ± 2.2 km), 11.8 ± 2.1 km (11.5 ± 2.3 km), 1.87 ± 0.83 km (1.52 ± 0.71 km), and 10.5 ± 2.2 km, -46.9 ± 9.7°C (-47.1 ± 10.0°C).These properties exhibited seasonal variations, with cirrus clouds reaching higher altitudes in summer and lower in winter, influenced by the height of the tropopause. The optical properties of cirrus clouds were also analyzed, showing an annual average optical depth of 0.31 ± 0.35 for ground-based lidar and 0.32 ± 0.44 for CALIOP. The study highlighted the distribution of subvisible, thin, and thick cirrus clouds, with a notable prevalence of subvisible clouds during summer, suggesting their frequent formation above 14 km. Furthermore, the study observed linear growth in geometric thickness and optical depth up to 2.5 km from CALIOP and 2.9 km from ground-based lidar. Maximum optical depth was observed at cloud centroid temperatures of -35°C for CALIOP and -40°C for ground-based lidar, with optical depth decreasing as temperatures fell. This suggests that fully glaciated cirrus clouds exhibit the highest optical depth at warmer temperatures, within the complete glaciation temperature range of -35°C to -40°C.

17.
Glob Chang Biol ; 30(6): e17348, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38822656

RESUMO

Global climate change intensifies the water cycle and makes freshest waters become fresher and vice-versa. But how this change impacts phytoplankton in coastal, particularly harmful algal blooms (HABs), remains poorly understood. Here, we monitored a coastal bay for a decade and found a significant correlation between salinity decline and the increase of Karenia mikimotoi blooms. To examine the physiological linkage between salinity decreases and K. mikimotoi blooms, we compare chemical, physiological and multi-omic profiles of this species in laboratory cultures under high (33) and low (25) salinities. Under low salinity, photosynthetic efficiency and capacity as well as growth rate and cellular protein content were significantly higher than that under high salinity. More strikingly, the omics data show that low salinity activated the glyoxylate shunt to bypass the decarboxylation reaction in the tricarboxylic acid cycle, hence redirecting carbon from CO2 release to biosynthesis. Furthermore, the enhanced glyoxylate cycle could promote hydrogen peroxide metabolism, consistent with the detected decrease in reactive oxygen species. These findings suggest that salinity declines can reprogram metabolism to enhance cell proliferation, thus promoting bloom formation in HAB species like K. mikimotoi, which has important ecological implications for future climate-driven salinity declines in the coastal ocean with respect to HAB outbreaks.


Assuntos
Mudança Climática , Proliferação Nociva de Algas , Salinidade , Fotossíntese , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/fisiologia , Carbono/metabolismo , Carbono/análise
18.
Langmuir ; 40(31): 16511-16520, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39072506

RESUMO

An intelligent delivery nanoformulation could enhance the utilization efficacy, uptake, and translocation of pesticides in plants. Herein, a redox/pH-triggered and fluorescent smart delivery nanoformulation was designed and constructed by using hollow mesoporous organosilica nanoparticles (HMONs) and ZnO quantum dots as the nanocarrier and capping agent, respectively. Boscalid was further loaded to generate Boscalid@HMONs@ZnO with a loading rate of 9.8% for controlling Botrytis cinerea (B. cinerea). The quantity of boscalid released by Boscalid@HMONs@ZnO in a glutathione environment or at pH 3.0 was 1.3-fold and 1.9-fold higher than that in a neutral condition. Boscalid@HMONs@ZnO has 1.7-fold the toxicity index of boscalid technical against B. cinerea in antifungal experiments. Pot experiments revealed that the efficacy of Boscalid@HMONs@ZnO was significantly enhanced more than 1.27-fold compared to commercially available water-dispersible granules of boscalid. Due to the fluorescence properties of Boscalid@HMONs@ZnO, pesticide transport's real-time monitoring of pesticide translocation in tomato plants could be observed by confocal laser scanning microscopy. Fluorescence images revealed that HMONs@ZnO had been effectively transported via treated leaves or roots in tomato plants. This research showed the successful application of HMONs@ZnO as a nanocarrier for controlling disease and offered an effective avenue to explore the real-time tracking of pesticide translocation in plants.


Assuntos
Botrytis , Nanopartículas , Oxirredução , Óxido de Zinco , Botrytis/efeitos dos fármacos , Nanopartículas/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Concentração de Íons de Hidrogênio , Corantes Fluorescentes/química , Compostos de Bifenilo/química , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Solanum lycopersicum/química , Praguicidas/química , Praguicidas/toxicidade , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Compostos de Organossilício/química , Compostos de Organossilício/farmacologia , Liberação Controlada de Fármacos , Fungicidas Industriais/química , Fungicidas Industriais/farmacologia , Niacinamida/análogos & derivados
19.
Langmuir ; 40(26): 13688-13698, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38902198

RESUMO

The structure-property relationship of poly(vinyl chloride) (PVC)/CaCO3 nanocomposites is investigated by all-atom molecular dynamics (MD) simulations. MD simulation results indicate that the dispersity of nanofillers, interfacial bonding, and chain mobility are imperative factors to improve the mechanical performance of nanocomposites, especially toughness. The tensile behavior and dissipated work of the PVC/CaCO3 model demonstrate that 12 wt % CaCO3 modified with oleate anion and dodecylbenzenesulfonate can impart high toughness to PVC due to its good dispersion, favorable interface interaction, and weak migration of PVC chains. Under the guidance of MD simulation, we experimentally prepared a transparent PVC/CaCO3 nanocomposite with good mechanical properties by in situ polymerization of monodispersed CaCO3 in vinyl chloride monomers. Interestingly, experimental tests indicate that the optimum toughness of a nanocomposite (a 368% increase in the elongation at break and 204% improvement of the impact strength) can be indeed realized by adding 12 wt % CaCO3 modified with oleic acid and dodecylbenzenesulfonic acid, which is remarkably consistent with the MD simulation prediction. In short, this work provides a proof-of-concept of using MD simulation to guide the experimental synthesis of PVC/CaCO3 nanocomposites, which can be considered as an example to develop other functional nanocomposites.

20.
Circ Res ; 131(11): 893-908, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36268709

RESUMO

BACKGROUND: Inflammation resolution and cardiac repair initiation after myocardial infarction (MI) require timely activation of reparative signals. Histone lactylation confers macrophage homeostatic gene expression signatures via transcriptional regulation. However, the role of histone lactylation in the repair response post-MI remains unclear. We aimed to investigate whether histone lactylation induces reparative gene expression in monocytes early and remotely post-MI. METHODS: Single-cell transcriptome data indicated that reparative genes were activated early and remotely in bone marrow and circulating monocytes before cardiac recruitment. Western blotting and immunofluorescence staining revealed increases in histone lactylation levels, including the previously identified histone H3K18 lactylation in monocyte-macrophages early post-MI. Through joint CUT&Tag and RNA-sequencing analyses, we identified Lrg1, Vegf-a, and IL-10 as histone H3K18 lactylation target genes. The increased modification and expression levels of these target genes post-MI were verified by chromatin immunoprecipitation-qPCR and reverse transcription-qPCR. RESULTS: We demonstrated that histone lactylation regulates the anti-inflammatory and pro-angiogenic dual activities of monocyte-macrophages by facilitating reparative gene transcription and confirmed that histone lactylation favors a reparative environment and improves cardiac function post-MI. Furthermore, we explored the potential positive role of monocyte histone lactylation in reperfused MI. Mechanistically, we provided new evidence that monocytes undergo metabolic reprogramming in the early stage of MI and demonstrated that dysregulated glycolysis and MCT1 (monocarboxylate transporter 1)-mediated lactate transport promote histone lactylation. Finally, we revealed the catalytic effect of IL (interleukin)-1ß-dependent GCN5 (general control non-depressible 5) recruitment on histone H3K18 lactylation and elucidated its potential role as an upstream regulatory element in the regulation of monocyte histone lactylation and downstream reparative gene expression post-MI. CONCLUSIONS: Histone lactylation promotes early remote activation of the reparative transcriptional response in monocytes, which is essential for the establishment of immune homeostasis and timely activation of the cardiac repair process post-MI.


Assuntos
Histonas , Infarto do Miocárdio , Humanos , Histonas/metabolismo , Ativação Transcricional , Infarto do Miocárdio/metabolismo , Macrófagos/metabolismo , Monócitos/metabolismo
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