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1.
Nat Commun ; 15(1): 3520, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664402

RESUMO

The root-associated microbiota plays an important role in the response to environmental stress. However, the underlying mechanisms controlling the interaction between salt-stressed plants and microbiota are poorly understood. Here, by focusing on a salt-tolerant plant wild soybean (Glycine soja), we demonstrate that highly conserved microbes dominated by Pseudomonas are enriched in the root and rhizosphere microbiota of salt-stressed plant. Two corresponding Pseudomonas isolates are confirmed to enhance the salt tolerance of wild soybean. Shotgun metagenomic and metatranscriptomic sequencing reveal that motility-associated genes, mainly chemotaxis and flagellar assembly, are significantly enriched and expressed in salt-treated samples. We further find that roots of salt stressed plants secreted purines, especially xanthine, which induce motility of the Pseudomonas isolates. Moreover, exogenous application for xanthine to non-stressed plants results in Pseudomonas enrichment, reproducing the microbiota shift in salt-stressed root. Finally, Pseudomonas mutant analysis shows that the motility related gene cheW is required for chemotaxis toward xanthine and for enhancing plant salt tolerance. Our study proposes that wild soybean recruits beneficial Pseudomonas species by exudating key metabolites (i.e., purine) against salt stress.


Assuntos
Soja , Raízes de Plantas , Pseudomonas , Rizosfera , Pseudomonas/genética , Pseudomonas/metabolismo , Soja/microbiologia , Soja/metabolismo , Soja/genética , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo , Microbiota/efeitos dos fármacos , Purinas/metabolismo , Purinas/farmacologia , Estresse Salino/genética , Quimiotaxia/genética , Tolerância ao Sal/genética , Microbiologia do Solo , Xantina/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética
2.
MedComm (2020) ; 5(5): e521, 2024 May.
Artigo em Catalão | MEDLINE | ID: mdl-38660687

RESUMO

This study systematically analyzed the molecular mechanism and function of nuclear factor kappa B subunit 2 (NFKB2) in colorectal cancer (CRC) to investigate the potential of NFKB2 as a therapeutic target for CRC. Various experimental techniques, including RNA sequencing, proteome chip assays, and small molecule analysis, were used to obtain a deeper understanding of the regulation of NFKB2 in CRC. The results revealed that NFKB2 was upregulated in a significant proportion of patients with advanced hepatic metastasis of CRC. NFKB2 played an important role in promoting tumor growth through CD8+ T-cell exhaustion. Moreover, NFKB2 directly interacted with signal transducer and activator of transcription 2 (STAT2), leading to increased phosphorylation of STAT2 and the upregulation of programmed death ligand 1 (PD-L1). Applying a small molecule inhibitor of NFKB2 (Rg5) led to a reduction in PD-L1 expression and improved response to programmed death-1 blockade-based immunotherapy. In conclusion, the facilitated NFKB2-STAT2/PD-L1 axis may suppress immune surveillance in CRC and targeting NFKB2 may enhance the efficacy of immunotherapeutic strategies. Our results provide novel insights into the molecular mechanisms underlying the contribution of NFKB2 in CRC immune escape.

3.
Chemosphere ; : 141919, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641291

RESUMO

The global concern surrounding pollution caused by phthalates is escalating, with dimethyl phthalate (DMP) emerging as one of the most prevalent contaminants within the phthalates (PAEs) category. Although the biodegradation of DMP is considered both safe and efficient, its underlying degradation mechanism is not yet fully elucidated, and the degradation performance can be somewhat inconsistent. To address this issue, our study isolated a DMP-degrading bacterium (DNM-S1) from a vegetable greenhouse. The resulting data revealed that DNM-S1 exhibited a remarkable degradation performance, successfully degrading 84.98% of a 2000 mg L-1 DMP solution within 72 h. Remarkably, it achieved complete degradation of a 50 mg L-1 DMP solution within just 3 h. DMP degradation by DNM-S1 was also found to be efficient even under low-temperature conditions (10 °C). Our research further indicates that DNM-S1 is capable of capturing DMP through the ester bond in the bacterium's cell wall fatty acids, forming hydrogen bonds through hydrophobic interactions. The DMP was then transported into the DNM-S1 protoplasm using an active transport mechanism. Interestingly, the secondary metabolites of DNM-S1 contained natural carotenoids, which could potentially counteract the damaging effects of PAEs on cell membrane permeability. In summary, these findings highlight the potential of DNM-S1 in addressing PAEs pollution and provide new insights into the metabolic mechanism of PAEs degradation.

4.
Nano Lett ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626333

RESUMO

The performance of blue quantum dot light-emitting diodes (QLEDs) is limited by unbalanced charge injection, resulting from insufficient holes caused by low mobility or significant energy barriers. Here, we introduce an angular-shaped heteroarene based on cyclopentane[b]thiopyran (C8-SS) to modify the hole transport layer poly-N-vinylcarbazole (PVK), in blue QLEDs. C8-SS exhibits high hole mobility and conductivity due to the π···π and S···π interactions. Introducing C8-SS to PVK significantly enhanced hole mobility, increasing it by 2 orders of magnitude from 2.44 × 10-6 to 1.73 × 10-4 cm2 V-1 s-1. Benefiting from high mobility and conductivity, PVK:C8-SS-based QLEDs exhibit a low turn-on voltage (Von) of 3.2 V. More importantly, the optimized QLEDs achieve a high peak power efficiency (PE) of 7.13 lm/W, which is 2.65 times that of the control QLEDs. The as-proposed interface engineering provides a novel and effective strategy for achieving high-performance blue QLEDs in low-energy consumption lighting applications.

5.
bioRxiv ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38562745

RESUMO

Tissue stem cells often exhibit developmental stage-specific and sexually dimorphic properties, but the underlying mechanism remains largely elusive. By characterizing IGF1R signaling in hematopoietic cells, here we report that its disruption exerts sex-specific effects in adult hematopoietic stem and progenitor cells (HSPCs). Loss of IGF1R decreases the HSPC population in females but not in males, in part due to a reduction in HSPC proliferation induced by estrogen. In addition, the adult female microenvironment enhances engraftment of wild-type but not Igf1r-null HSPCs. In contrast, during gestation, when both female and male fetuses are exposed to placental estrogens, loss of IGF1R reduces the numbers of their fetal liver HSPCs regardless of sex. Collectively, these data support the interplay of IGF1R and estrogen pathways in HSPCs and suggest that the proliferation-promoting effect of estrogen on HSPCs is in part mediated via IGF1R signaling.

6.
Free Radic Biol Med ; 218: 26-40, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38570172

RESUMO

Nuclear factor erythroid 2-related factor 2 (Nrf2) plays a crucial role in ferroptosis by regulating the cellular antioxidant response and maintaining redox balance. However, compounds that induce ferroptosis through dual antioxidant pathways based on Nrf2 have not been fully explored. In our study, we investigated the impact of Gambogic acid (GA) on MCF-7 cells and HepG2 cells in vitro. The cytotoxicity, colony formation assay and cell cycle assay demonstrated potent tumor-killing ability of GA, while its effect was rescued by ferroptosis inhibitors. Furthermore, RNA sequencing revealed the enrichment of ferroptosis pathway mediated by GA. In terms of ferroptosis indicators detection, evidences for GA were provided including reactive oxygen species (ROS) accumulation, alteration in mitochondrial membrane potential (MMP), disappearance of mitochondrial cristae, lipid peroxidation induction, malondialdehyde (MDA) accumulation promotion, iron ion accumulation as well as glutathione (GSH)/thioredoxin (Trx) depletion. Notably, Ferrostatin-1 (Fer-1) and Liproxstatin-1 (Lip-1) successfully rescued GA-induced MDA accumulation. In terms of mechanism, Nrf2 was found to play a pivotal role in GA-induced ferroptosis by inducing protein alterations through the iron metabolism pathway and GSH/Trx dual antioxidant pathway. Furthermore, GA exerted good antitumor activity in vivo through GSH/Trx dual antioxidant pathway, and Fer-1 significantly attenuated its efficacy. In conclusion, our findings first provided new evidence for GA as an inducer of ferroptosis, and Nrf2-mediated GSH/Trx dual antioxidant system played an important role in GA-induced ferroptosis.

7.
Plant Commun ; : 100891, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561965

RESUMO

Plants grown under extreme environments represent unique sources for stress-resistant genes and mechanisms. Ammopiptanthus mongolicus (Leguminosae) is a xerophytic legume shrub with evergreen broadleaves native to the semi-arid and desert regions, however, its drought tolerance mechanisms have not been well understood. Here, we report the assembly of a reference-grade genome, its evolutionary history within the legume family, and examination to its drought tolerance mechanisms. The assembled genome size was 843.07 Mb and 98.7% of the assembly was successfully anchored to the nine chromosomes of the plant. 47,611 genes were predicted to be protein-coding and 70.71% of the genome is composed of repetitive sequences dominated by transposable elements, particularly long-terminal-repeat retrotransposons (LTR-RTs). Evolutionary analyses revealed two whole-genome duplication (WGD) events shared by the genus Ammopiptanthus and other legumes at 130 and 58 million years ago (Mya), whereas no species-specific WGD was found within this genus. Further ancestral genome reconstruction indicated that the A. mongolicus genome had fewer rearrangements within the legume family, confirming it is a "relict plant". Transcriptomic analyses revealed that cuticular wax biosynthesis and transport genes were highly expressed under both normal and polyethylene glycol (PEG)-induced dehydration conditions, and significant induction of ethylene biosynthesis and signaling related genes was also observed in leaves experiencing the dehydration stress, indicating that enhanced ethylene response and formation of thick waxy cuticles are two major mechanisms of drought tolerance in A. mongolicus. Consistently, ectopic expression of AmERF2, an ethylene response factor unique for A. mongolicus, resulted in marked increase of drought tolerance in transgenic Arabidopsis thaliana plants, demonstrating the application potential of A. mongolicus genes in crop improvement.

8.
Environ Sci Technol ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653761

RESUMO

Nitrous oxide (N2O) is a potent greenhouse gas with a high global warming potential, emphasizing the critical need to develop efficient elimination methods. Electrocatalytic N2O reduction reaction (N2ORR) stands out as a promising approach, offering room temperature conversion of N2O to N2 without the production of NOx byproducts. In this study, we present the synthesis of a copper-based single-atom catalyst featuring atomic Cu on nitrogen-doped carbon black (Cu1-NCB). Attributed to the highly dispersed single-atom Cu sites and the effective suppression of the hydrogen evolution reaction, Cu1-NCB demonstrated an optimal N2 faradaic efficiency (82.1%) and yield rate (3.53 mmol h-1 mgmetal-1) at -0.2 and -0.5 V vs RHE, respectively, outperforming previously reported N2ORR electrocatalysts. Further, a gas diffusion electrode cell was employed to improve mass transfer and achieved a 28.6% conversion rate of 30% N2O with only a 14 s residence time, demonstrating the potential for practical application. Density functional theory calculations identified Cu-N4 as the crucial active site for N2ORR, highlighting the significance of the unsaturated coordination and metal-support electronic structure. O-terminal adsorption of N2O was favored, and the dissociative adsorption (*ON2 → *O + N2) was the rate-determining step. These findings reveal the broad prospects of N2O decomposition via electrocatalysis.

9.
Huan Jing Ke Xue ; 45(5): 3088-3097, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629569

RESUMO

Mulching to conserve moisture has become an important agronomic practice in saline soil cultivation, and the effects of the dual stress of salinity and microplastics on soil microbes are receiving increasing attention. In order to investigate the effect of polyethylene microplastics on the microbial community of salinized soils, this study investigated the effects of different types (chloride and sulphate) and concentrations (weak, medium, and strong) of polyethylene (PE) microplastics (1% and 4% of the dry weight mass of the soil sample) on the soil microbial community by simulating microplastic contamination in salinized soil environments indoors. The results showed that:PE microplastics reduced the diversity and abundance of microbial communities in salinized soils and were more strongly affected by sulphate saline soil treatments. The relative abundance of each group of bacteria was more strongly changed in the sulphate saline soil treatment than in the chloride saline soil treatment. At the phylum level, the relative abundance of Proteobacteria was positively correlated with the abundance of fugitive PE microplastics, whereas the relative abundances of Bacteroidota, Actinobacteriota, and Acidobacteria were negatively correlated with the abundance of fugitive PE microplastics. At the family level, the relative abundances of Flavobacteriaceae, Alcanivoracaceae, Halomonadaceae, and Sphingomonasceae increased with increasing abundance of PE microplastics. The KEGG metabolic pathway prediction showed that the relative abundance of microbial metabolism and genetic information functions were reduced by the presence of PE microplastics, and the inhibition of metabolic functions was stronger in sulphate saline soils than in chloride saline soils, whereas the inhibition of genetic information functions was weaker than that in chloride saline soils. The secondary metabolic pathways of amino acid metabolism, carbohydrate metabolism, and energy metabolism were inhibited. It was hypothesized that the reduction in metabolic functions may have been caused by the reduced relative abundance of the above-mentioned secondary metabolic pathways. This study may provide a theoretical basis for the study of the effects of microplastics and salinization on the soil environment under the dual pollution conditions.


Assuntos
Microplásticos , Polietileno , Plásticos , Solo , Cloretos , Halogênios , Sulfatos , Microbiologia do Solo
10.
Int J Nanomedicine ; 19: 3405-3421, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617795

RESUMO

Background: Natural nanoparticles have been found to exist in traditional Chinese medicine (TCM) decoctions. However, whether natural nanoparticles can influence the oral bioavailability of active compounds has not been elucidated. Using Xie-Bai-San decoction (XBSD) as an example, the purpose of this study was to isolate, characterize and elucidate the mechanism of the nanoparticles (N-XBSD) in XBSD, and further to explore whether the bioavailability of the main active compounds could be enhanced by N-XBSD. Methods: N-XBSD were isolated from XBSD, and investigated its characterization and study of its formation mechanism, and evaluation of its ability to enhance bioavailability of active compounds. Results: The N-XBSD was successfully isolated with the average particle size of 104.53 nm, PDI of 0.27 and zeta potential of -5.14 mV. Meanwhile, all the eight active compounds were most presented in N-XBSD. Kukoamine B could self-assemble with mulberroside A or liquiritin to form nanoparticles, respectively. And the FT-IR and HRMS results indicated the possible binding of the ammonium group of kukoamine B with the phenolic hydroxyl group of mulberroside A or liquiritin, respectively. The established UPLC-MS/MS method was accurate and reliable and met the quantitative requirements. The pharmacokinetic behaviors of the N-XBSD and decoction were similar in rats. Most notably, compared to that of free drugs, the Cmax, AUC0-∞, AUC0-t, T1/2 and MRT0-∞ values of index compounds were the higher in N-XBSD, with a slower plasma clearance rate in rats. Conclusion: The major active compounds of XBSD were mainly distributed in N-XBSD, and N-XBSD was formed through self-assembly among active compounds. N-XBSD could obviously promote the bioavailability of active compounds, indicating natural nanoparticles of decoctions play an important role in therapeutic effects.


Assuntos
Ácidos Cafeicos , Dissacarídeos , Nanopartículas , Espermina/análogos & derivados , Estilbenos , Espectrometria de Massas em Tandem , Animais , Ratos , Disponibilidade Biológica , Cromatografia Líquida , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Front Microbiol ; 15: 1335818, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628860

RESUMO

This study was conducted to investigate the effects of dietary energy levels on microorganisms and short-chain fatty acids (SCFAs) of rumen and the expression of tight junction proteins in Honghe Yellow cattle. A total of fifteen male Honghe Yellow cattle were randomly divided into three treatments (five replicates per treatment), consisting of formulated energy concentrations of 5.90 MJ/kg (high-energy diet, group H), 5.60 MJ/kg (medium-energy diet, group M) and 5.30 MJ/kg (low-energy diet, group L). The results showed that compared with group H, the expression of Claudin-1 in rumen epithelium of groups M and L was increased, but the expression of ZO-1 was decreased (p < 0.05). Moreover, compared with group H, group M down-regulated the expression of Occludin and Claudin-1 in the brain (p < 0.05). For rumen bacteria, the dominant phyla included Bacteroidetes and Firmicutes, the abundance of Actinobacteriota in groups M and L was significantly increased compared with group H (p < 0.05). At the genus level, the relative abundance of Corynebacterium, Eubacterium_nodatum_group and Neisseraceae in groups M and L was significantly decreased compared with group H (p < 0.05). For rumen fungi, the dominant phyla included Basidiomycota, Ascomycota and Neocariastigomycota, the relative abundance of Ascomycetes was significantly higher than that of groups M and L compared with group H (p < 0.05). At the genus level, the relative abundance of Neocelimastigaceae and Myceliophthora in groups M and L was significantly reduced compared with group H (p < 0.05). Furthermore, the expression of Claudin-1 in rumen epithelium was significantly positively correlated with Actinobacteriota, Corynebacterium and Neisseriaceae. The expression of ZO-1 in the spinal cord was significantly positively correlated with Myceliophthora. The expression of Occludin in brain was positively correlated with valerate content (p < 0.05). In summary, dietary energy levels affected the rumen microbiota of Honghe Yellow cattle. The expression of Claudin-1 in rumen epithelium and the total SCFAs concentration were increased with decreasing dietary energy levels, but the expression of Claudin-1 in brain and ZO-1 in the spinal cord were reduced with decreasing dietary energy levels. Meanwhile, the rumen microbiota and SCFAs were significantly correlated with the expression of TJP.

12.
Front Public Health ; 12: 1295531, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633228

RESUMO

Objective: The aim of this study was to evaluate the present status of self-management behavior and glycemic control in individuals diagnosed with Type 2 Diabetes Mellitus (T2D), as well as to examine the impact of health quotient (HQ) and time management skills on both self-management behavior and glycemic control. Methods: Between October 2022 and March 2023, a purposive sampling method had been utilized to select 215 participants with type T2D. The survey concluded a general information questionnaire, an HQ scale, a diabetes time management questionnaire and a self-management behavior questionnaire. The health quotient(HQ)encompasses the individuals' knowledge, attitude toward health, and the ability to maintain their own well-being. The diabetes time management questionnaire was reverse-scored, with higher scores indicating an enhanced competence in time management. The path among variables was analyzed using structural equation modeling(SEM). Results: SEM showed that the direct effect of HQ on time management was -0.566 (p < 0.05), the direct effect of time management on the effect of self-management was -0.617 (p < 0.05), the direct effect of HQ on self-management was 0.156, and the indirect effect was 0.349 (p < 0.05); the relationship between health quotient and self-management was partially mediated by time management, with a mediating effect size of 68.8%. In addition, self-management had a direct effect on HbAlc, with a size of -0.394 (p < 0.05); The impacts of both HQ and time management on HbAlc were found to be mediated by self-management, with HQ demonstrating an indirect effect of -0.199 (p < 0.05) and time management showing an indirect effect of 0.244 (p < 0.05). Conclusion: Health quotient and time management in patients with T2D serve as catalysts for self-management behavior. They affect HbAlc level indirectly through self-management practices. The suggestion is to prioritize the cultivation of rational time organization and management skills in T2D patients, as well as enhance their health quotient level. This can facilitate a more effective improvement in patients' self-management behaviors, ultimately achieving the objective of maintaining optimal glycemic control.


Assuntos
Diabetes Mellitus Tipo 2 , Autogestão , Humanos , Autogestão/métodos , Gerenciamento do Tempo , Controle Glicêmico , Glicemia
13.
Front Public Health ; 12: 1332095, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633232

RESUMO

Introduction: Adolescent suicide is a prevalent issue globally, with various factors contributing to this phenomenon. This study aimed to investigate these factors and their interrelationships to better understand the causes of adolescent suicide and provide evidence for its prevention. Methods: This study conducted among middle school students in Liaoning Province, China, from April to May 2016, A cross-sectional survey was administered to 1,028 students aged 10-19, using instruments such as the Behavior Questionnaire-Revised (SBQ-R), Children's Perception of Interparental Conflict Scale (CPIC), and revised version of Inventory of Parent Attachment (IPPA-R). Result: Binary logistic regression analysis revealed that adolescents aged 15-19, adolescents with strong perceptions of parental conflict were at high risk of suicide intention. Adolescents living in rural areas, adolescents with high mother-child attachment, adolescents with high father-child attachment were at low risk of suicide intention. Furthermore, parent-child attachment played a mediating role between two dimensions of parental conflict perception (resolved situations and response effect) and suicide intention. Discussion: The study concludes that adolescents living in urban areas, older adolescents, adolescents with a high level of parental conflict intensity, and those with low levels of parent-child attachment are at high risk of suicide intention. parent-child attachment played a mediating role between two dimensions of parental conflict perception (resolved situations and response effect) and suicide intention. Interventions aimed at reducing family conflicts and improving parent-child relationships are recommended to decrease the incidence of adolescent suicide.


Assuntos
Pais , Suicídio , Adolescente , Humanos , Estudos Transversais , Relações Pais-Filho , China/epidemiologia , Estudantes
14.
Cardiovasc Diabetol ; 23(1): 121, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38581024

RESUMO

BACKGROUND: This study investigates the relationship between triglyceride-glucose (TyG) index trajectories and the results of ablation in patients with stage 3D atrial fibrillation (AF). METHODS: A retrospective cohort study was carried out on patients who underwent AF Radiofrequency Catheter Ablation (RFCA) at the Cardiology Department of the Fourth Affiliated Hospital of Zhejiang University and Taizhou Hospital of Zhejiang Province from January 2016 to December 2022. The main clinical endpoint was determined as the occurrence of atrial arrhythmia for at least 30 s following a 3-month period after ablation. Using a latent class trajectory model, different trajectory groups were identified based on TyG levels. The relationship between TyG trajectory and the outcome of AF recurrence in patients was assessed through Kaplan-Meier survival curve analysis and multivariable Cox proportional hazards regression model. RESULTS: The study included 997 participants, with an average age of 63.21 ± 9.84 years, of whom 630 were males (63.19%). The mean follow-up period for the participants was 30.43 ± 17.75 months, during which 200 individuals experienced AF recurrence. Utilizing the minimum Bayesian Information Criterion (BIC) and the maximum Entropy principle, TyG levels post-AF RFCA were divided into three groups: Locus 1 low-low group (n = 791), Locus 2 low-high-low group (n = 14), and Locus 3 high-high group (n = 192). Significant differences in survival rates among the different trajectories were observed through the Kaplan-Meier curve (P < 0.001). Multivariate Cox regression analysis showed a significant association between baseline TyG level and AF recurrence outcomes (HR = 1.255, 95% CI: 1.087-1.448). Patients with TyG levels above 9.37 had a higher risk of adverse outcomes compared to those with levels below 8.67 (HR = 2.056, 95% CI: 1.335-3.166). Furthermore, individuals in Locus 3 had a higher incidence of outcomes compared to those in Locus 1 (HR = 1.580, 95% CI: 1.146-2). CONCLUSION: The TyG trajectories in patients with stage 3D AF are significantly linked to the outcomes of AF recurrence. Continuous monitoring of TyG levels during follow-up may help in identifying patients at high risk of AF recurrence, enabling the early application of effective interventions.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/etiologia , Estudos Retrospectivos , Teorema de Bayes , Resultado do Tratamento , Fatores de Risco , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Recidiva
15.
Nat Commun ; 15(1): 3143, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609359

RESUMO

Largely removed from anthropogenic delivery of nitrogen (N), Antarctica has notably low levels of nitrogen. Though our understanding of biological sources of ammonia have been elucidated, the microbial drivers of nitrate (NO3-) cycling in coastal Antarctica remains poorly understood. Here, we explore microbial N cycling in coastal Antarctica, unraveling the biological origin of NO3- via oxygen isotopes in soil and lake sediment, and through the reconstruction of 1968 metagenome-assembled genomes from 29 microbial phyla. Our analysis reveals the metabolic potential for microbial N2 fixation, nitrification, and denitrification, but not for anaerobic ammonium oxidation, signifying a unique microbial N-cycling dynamic. We identify the predominance of complete ammonia oxidizing (comammox) Nitrospira, capable of performing the entire nitrification process. Their adaptive strategies to the Antarctic environment likely include synthesis of trehalose for cold stress, high substrate affinity for resource utilization, and alternate metabolic pathways for nutrient-scarce conditions. We confirm the significant role of comammox Nitrospira in the autotrophic, nitrification process via 13C-DNA-based stable isotope probing. This research highlights the crucial contribution of nitrification to the N budget in coastal Antarctica, identifying comammox Nitrospira clade B as a nitrification driver.


Assuntos
Amônia , Nitrificação , Regiões Antárticas , Resposta ao Choque Frio , Nitrogênio
16.
Mol Ther ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38584391

RESUMO

The clinical potential of current FDA-approved chimeric antigen receptor (CAR)-engineered T (CAR-T) cell therapy is encumbered by its autologous nature, which presents notable challenges related to manufacturing complexities, heightened costs, and limitations in patient selection. Therefore, there is a growing demand for off-the-shelf universal cell therapies. In this study, we have generated universal CAR-engineered NKT (UCAR-NKT) cells by integrating iNKT TCR engineering and HLA gene editing on hematopoietic stem cells (HSCs), along with an ex vivo, feeder-free HSC differentiation culture. The UCAR-NKT cells are produced with high yield, purity, and robustness, and they display a stable HLA-ablated phenotype that enables resistance to host cell-mediated allorejection. These UCAR-NKT cells exhibit potent antitumor efficacy to blood cancers and solid tumors, both in vitro and in vivo, employing a multifaceted array of tumor-targeting mechanisms. These cells are further capable of altering the tumor microenvironment by selectively depleting immunosuppressive tumor-associated macrophages and myeloid-derived suppressor cells. In addition, UCAR-NKT cells demonstrate a favorable safety profile with low risks of graft-versus-host disease and cytokine release syndrome. Collectively, these preclinical studies underscore the feasibility and significant therapeutic potential of UCAR-NKT cell products and lay a foundation for their translational and clinical development.

17.
Sci Immunol ; 9(94): eadg8817, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640251

RESUMO

CD4+ regulatory T (Treg) cells accumulate in the tumor microenvironment (TME) and suppress the immune system. Whether and how metabolite availability in the TME influences Treg cell differentiation is not understood. Here, we measured 630 metabolites in the TME and found that serine and palmitic acid, substrates required for the synthesis of sphingolipids, were enriched. A serine-free diet or a deficiency in Sptlc2, the rate-limiting enzyme catalyzing sphingolipid synthesis, suppressed Treg cell accumulation and inhibited tumor growth. Sphinganine, an intermediate metabolite in sphingolipid synthesis, physically interacted with the transcription factor c-Fos. Sphinganine c-Fos interactions enhanced the genome-wide recruitment of c-Fos to regions near the transcription start sites of target genes including Pdcd1 (encoding PD-1), which promoted Pdcd1 transcription and increased inducible Treg cell differentiation in vitro in a PD-1-dependent manner. Thus, Sptlc2-mediated sphingolipid synthesis translates the extracellular information of metabolite availability into nuclear signals for Treg cell differentiation and limits antitumor immunity.


Assuntos
Neoplasias , Esfingosina/análogos & derivados , Linfócitos T Reguladores , Humanos , Receptor de Morte Celular Programada 1/metabolismo , Serina/metabolismo , Esfingolipídeos/metabolismo , Microambiente Tumoral
18.
BMC Pregnancy Childbirth ; 24(1): 245, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582906

RESUMO

BACKGROUND AND AIMS: To investigate the impact of intrahepatic cholestasis of pregnancy (ICP) with hepatitis B virus (HBV) infection on pregnancy outcomes. METHODS: We selected 512 pregnant women, collected the data including maternal demographics, main adverse pregnancy outcomes and maternal HBV infected markers HBeAg and HBV-DNA loads status, then have a comparative analysis. RESULTS: There were 319 solitary ICP patients without HBV infection (Group I) and 193 ICP patients with HBV infection. Of the latter, there were 118 cases with abnormal liver function(Group II) and 80 cases with normal liver function(Group III). All HBV-infected pregnant women with ICP were divided into hepatitis Be antigen (HBeAg)-positive group (102 cases) and HBeAg-negative group (91 cases), according to the level of the serum HBeAg status; and into high viral load group (92 cases), moderate viral load group (46 cases) and low viral load group (55 cases) according to the maternal HBV-DNA level. Group II had a higher level of serum total bile acids, transaminase, bilirubin as well as a higher percentage of premature delivery, neonatal intensive care unit (NICU) admission and meconium-stained amniotic fluid (MSAF) compared with the other two groups(P < 0.05), but there were no significant differences in the above indicators between the Group I and Group III. Among the HBV-infected patients with ICP, HBeAg-positive group had a higher level of serum transaminase, bilirubin and bile acid as well as earlier gestational weeks of delivery, lower birth weight of new-borns and a higher rate of NICU admission than HBeAg-negative group (P < 0.05). Those with a high viral load (HBV-DNA > 106 IU/ml) had a higher level of transaminase, bilirubin, and bile acid as well as shorter gestational weeks of delivery, lower birth weight of new-borns and a higher rate of NICU admission compared with those with a low or moderate viral load (P < 0.05). CONCLUSION: HBV-infected pregnant women with ICP combined with abnormal liver function have more severe liver damage, a higher percentage of preterm birth and NICU admission. HBeAg-positive status and a high HBV-DNA load will increase the severity of conditions in HBV-infected pregnant women with ICP. HBV-infected patients with ICP who have abnormal liver function, HBeAg-positive or a high viral load should be treated more actively.


Assuntos
Colestase Intra-Hepática , Hepatite B , Complicações Infecciosas na Gravidez , Complicações na Gravidez , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Vírus da Hepatite B , Estudos Retrospectivos , Antígenos E da Hepatite B , Peso ao Nascer , DNA Viral , Antígenos de Superfície da Hepatite B , Nascimento Prematuro/epidemiologia , Hepatite B/complicações , Resultado da Gravidez/epidemiologia , Transaminases , Ácidos e Sais Biliares , Bilirrubina
19.
Chem Sci ; 15(9): 3262-3272, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38425519

RESUMO

The precisely engineered structures of materials greatly influence the manifestation of their properties. For example, in the process of alkali metal ion storage, a carefully designed structure capable of accommodating inserted and extracted ions will improve the stability of material cycling. The present study explores the uniform distribution of self-grown carbon nanotubes to provide structural support for the conductive and elastic MXene layers of Ti3C2Tx-Co@NCNTs. Furthermore, a compatible electrolyte system has been optimized by analyzing the solvation structure and carefully regulating the component in the solid electrolyte interphase (SEI) layer. Mechanistic studies demonstrate that the decomposition predominantly controlled by FSI- leads to the formation of a robust inorganic SEI layer enriched with KF, thus effectively inhibiting irreversible side reactions and major structural deterioration. Confirming our expectations, Ti3C2Tx-Co@NCNTs exhibits an impressive reversible capacity of 260 mA h g-1, even after 2000 cycles at 500 mA g-1 in 1 M KFSI (DME), surpassing most MXene-based anodes reported for PIBs. Additionally, density functional theory (DFT) calculations verify the superior electronic conductivity and lower K+ diffusion energy barriers of the novel superstructure of Ti3C2Tx-Co@NCNTs, thereby affirming the improved electrochemical kinetics. This study presents systematic evaluation methodologies for future research on MXene-based anodes in PIBs.

20.
Sci Rep ; 14(1): 1388, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438385

RESUMO

Aircraft icing deteriorates aerodynamic performance and reduces stall angle of attack, the fast convergence rate of tracking error is required to stabilize the aircraft when aircraft icing occurs. The state-of-the-art control methods for icing aircraft mostly assume that the icing of aircraft is instantaneous. Aiming at these issues, a fixed-time angle of attack-constrained control strategy is designed considering dynamic icing process. In order to explore the variation of aerodynamic coefficients in the process of dynamic icing, an ice wind tunnel experiment is implemented, and the relationship between lift coefficient, drag coefficient and pitching moment coefficient with angle of attack and icing intensity is obtained by fitting method. In order to prevent the stalling problem caused by the decrease of the stalling angle of attack in the process of dynamic icing, a method to determine the stalling angle of attack based on deep neural network is proposed. Considering the asymmetric and time-varying angle of attack constraint, a fixed-time convergent angle of attack-constrained robust control method is designed. The ice wind tunnel experiment shows the process of dynamic icing of the airfoil, and the simulation results verify the effectiveness of the proposed control method.

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