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1.
Crit Rev Clin Lab Sci ; : 1-15, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38957015

RESUMO

RNA methylation is a widespread regulatory mechanism that controls gene expression in physiological processes. In recent years, the mechanisms and functions of RNA methylation under diseased conditions have been increasingly unveiled by RNA sequencing technologies with large scale and high resolution. In this review, the fundamental concept of RNA methylation is introduced, and the common types of transcript methylation and their machineries are described. Then, the regulatory roles of RNA methylation, particularly N6-methyladenosine and 5-methylcytosine, in the vascular lesions of ocular and cardiopulmonary diseases are discussed and compared. The ocular diseases include corneal neovascularization, retinopathy of prematurity, diabetic retinopathy, and pathologic myopia; whereas the cardiopulmonary ailments involve atherosclerosis and pulmonary hypertension. This review hopes to shed light on the common regulatory mechanisms underlying the vascular lesions in these ocular and cardiopulmonary diseases, which may be conducive to developing therapeutic strategies in clinical practice.

2.
Int J Biol Macromol ; : 133551, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38997845

RESUMO

In this study, the curcumin was firstly encapsulated in gelatin (GLT) and/or cellulose nanocrystals (CNC) stabilized emulsions, then further mixed with sodium alginate (SA) to form emulsion-filled hydrogel beads loaded with curcumin (Cur). The Cur-loaded emulsions showed a droplet size of 20.3-24.4 µm with a uniform distribution. Introducing CNC and/or SA increased the viscosity of emulsions accompanied by viscoelastic transition, while the modulus was reduced due to destruction of GLT gel. Cur was doubly immobilized in the hydrogel beads with >90 % of encapsulation efficiency. The results of simulated gastrointestinal tract experiments revealed that the beads possessed a good pH sensitivity and controlled release behavior to prolong the retention of Cur in the gastrointestinal tract. After 6 h of UV irradiation, the Cur-loaded emulsion-filled hydrogel beads showed a higher antioxidant activity than that of pure Cur, effectively delaying the photodegradation of Cur. In addition, the beads had better stability in aqueous and acidic environments, which was favorable for prolonging the release of Cur. These results suggest that the emulsion-filled hydrogel beads have great potential for the delivery of lipophilic bioactive molecules.

3.
PeerJ ; 12: e17657, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39011384

RESUMO

Background: Our previous studies have successfully reported the reprogramming of fibroblasts into induced mammary epithelial cells (iMECs). However, the regulatory relationships and functional roles of MicroRNAs (miRNAs) in the progression of fibroblasts achieving the cell fate of iMECs are insufficiently understood. Methods: First, we performed pre-and post-induction miRNAs sequencing analysis by using high-throughput sequencing. Following that, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment studies were used to determine the primary roles of the significantly distinct miRNAs and targeted genes. Finally, the effect of miR-222-3p on iMECs fate reprogramming in vitro by transfecting. Results: As a result goat ear fibroblasts (GEFs) reprogramming into iMECs activates a regulatory program, involving 79 differentially expressed miRNAs. Besides, the programming process involved changes in multiple signaling pathways such as adherens junction, TGF-ß signaling pathway, GnRH secretion and the prolactin signaling pathway, etc. Furthermore, it was discovered that the expression of miR-222-3p downregulation by miR-222-3p inhibitor significantly increase the reprogramming efficiency and promoted lipid accumulation of iMECs.


Assuntos
Reprogramação Celular , Células Epiteliais , Fibroblastos , Cabras , MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Animais , Fibroblastos/metabolismo , Células Epiteliais/metabolismo , Feminino , Reprogramação Celular/genética , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Transdução de Sinais , Células Cultivadas , Regulação para Baixo
4.
Nat Prod Res ; : 1-9, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38824431

RESUMO

A novel cytochalasin named diaporchalasin A (1) bearing a cinnamenyl and an epoxy-macrocycloketone, and a new benzenepropionic acid derivative (2), and two known compounds (3 and 4) were isolated from Conus marmoreus-derived fungus Diaporthe sp. XMA007. Their structures were elucidated through detailed spectroscopic analysis, and the absolute configuration of 1 was determined by conformational analysis and TDDFT-ECD calculation. Their activity evaluation on PDE4 inhibition and breast cancer cell cytotoxicity were conducted, and compound 1 showed moderate inhibition on PDE4.

5.
J Infect Dev Ctries ; 18(5): 732-741, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38865392

RESUMO

INTRODUCTION: The absence of predictive models for early latent tuberculosis infection (LTBI) progression persists. This study aimed to create a screening model to identify high-risk LTBI patients prome to active tuberculosis (ATB) reactivation. METHODOLOGY: Patients with confirmed ATB were enrolled alongside LTBI individuals as a reference, with relevant clinical data gathered. LASSO regression cross-validation reduced data dimensionality. A nomogram was developed using multiple logistic regression, internally validated with Bootstrap resampling. Evaluation included C-index, receiver operating characteristic (ROC) curve, and calibration curves, with clinical utility assessed through decision curve analysis. RESULTS: The final nomogram incorporated serum albumin (OR = 1.337, p = 0.046), CD4+ (OR = 1.010, p = 0.004), and CD64 index (OR = 0.009, p = 0.020). The model achieved a C-index of 0.964, an area under the ROC curve of 0.962 (95% CI: 0.926-0.997), sensitivity of 0.971, and specificity of 0.910. Internal validation showed a mean absolute error of 0.013 and 86.4% identification accuracy. The decision curve indicated substantial net benefit at a risk threshold exceeding 10% (1: 9). CONCLUSIONS: This study established a biologically-rooted nomogram for high-risk LTBI patients prone to ATB reactivation, offering strong predictability, concordance, and clinical value. It serves as a personalized risk assessment tool, accurately identifying patients necessitating priority prophylactic treatment, complementing existing host risk factors effectively.


Assuntos
Tuberculose Latente , Nomogramas , Humanos , Tuberculose Latente/diagnóstico , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Medição de Risco/métodos , Curva ROC , Tuberculose/diagnóstico , Tuberculose/complicações , Fatores de Risco
7.
bioRxiv ; 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38853924

RESUMO

The design of bioelectronics capable of stably tracking brain-wide, single-cell, and millisecond-resolved neural activities in the developing brain is critical to the study of neuroscience and neurodevelopmental disorders. During development, the three-dimensional (3D) structure of the vertebrate brain arises from a 2D neural plate 1,2 . These large morphological changes previously posed a challenge for implantable bioelectronics to track neural activity throughout brain development 3-9 . Here, we present a tissue-level-soft, sub-micrometer-thick, stretchable mesh microelectrode array capable of integrating into the embryonic neural plate of vertebrates by leveraging the 2D-to-3D reconfiguration process of the tissue itself. Driven by the expansion and folding processes of organogenesis, the stretchable mesh electrode array deforms, stretches, and distributes throughout the entire brain, fully integrating into the 3D tissue structure. Immunostaining, gene expression analysis, and behavioral testing show no discernible impact on brain development or function. The embedded electrode array enables long-term, stable, brain-wide, single-unit-single-spike-resolved electrical mapping throughout brain development, illustrating how neural electrical activities and population dynamics emerge and evolve during brain development.

8.
Chin Med J (Engl) ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945693

RESUMO

ABSTRACT: Chronic hepatitis B virus (HBV) infection is a global public health concern. Existing antiviral drugs, including nucleos(t)ide analogs and interferon-α, can suppress HBV replication and improve the prognosis. However, the persistence of covalently closed circular DNA (cccDNA), the integration of HBV-DNA into the host genome, and compromised immune responses impede the successful treatment of hepatitis B. While achieving a functional cure of HBV remains elusive with the current treatment methods, this is the goal of new therapeutic approaches. Therefore, developing novel antiviral drugs is necessary for achieving a functional or complete cure for chronic hepatitis B. In recent years, substantial progress has been made in drug discovery and development for HBV infection. Direct-acting antiviral agents such as entry inhibitors, capsid assembly modulators, subviral particle release inhibitors, cccDNA silencers, and RNA interference molecules have entered clinical trials. In addition, several immunomodulatory agents, including toll-like receptor agonists, therapeutic vaccines, checkpoint inhibitors, and monoclonal antibodies, are also making their way toward clinical use. In this review, we summarize the recent progress and limitations of chronic hepatitis B treatment and discuss perspectives on approaches to achieving functional cure. Although it will take some time for these new antiviral drugs to be widely used in clinical practice, combination therapy may become a preferable treatment option in the future.

9.
Anal Chem ; 96(21): 8594-8603, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38718350

RESUMO

Solid-contact ion-selective electrodes (SC-ISEs) with ionophore-based polymer-sensitive membranes have been the major devices in wearable sweat sensors toward electrolyte analysis. However, the toxicity of ionophores in ion-selective membranes (ISMs), for example, valinomycin (K+ ion carrier), is a significant challenge, since the ISM directly contacts the skin during the tests. Herein, we report coating a hydrogel of graphene oxide-poly(vinyl alcohol) (GO-PVA) on the ISM to fabricate hydrogel-based SC-ISEs. The hydrogen bond interaction between GO sheets and PVA chains could enhance the mechanical strength through the formation of a cross-linking network. Comprehensive electrochemical tests have demonstrated that hydrogel-coated K+-SC-ISE maintains Nernstian response sensitivity, high selectivity, and anti-interference ability compared with uncoated K+-SC-ISE. A flexible hydrogel-based K+ sensing device was further fabricated with the integration of a solid-contact reference electrode, which has realized the monitoring of sweat K+ in real time. This work highlights the possibility of hydrogel coating for fabricating biocompatible wearable potentiometric sweat electrolyte sensors.

10.
Stat Theory Relat Fields ; 8(1): 1-14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800501

RESUMO

Missing data is unavoidable in longitudinal clinical trials, and outcomes are not always normally distributed. In the presence of outliers or heavy-tailed distributions, the conventional multiple imputation with the mixed model with repeated measures analysis of the average treatment effect (ATE) based on the multivariate normal assumption may produce bias and power loss. Control-based imputation (CBI) is an approach for evaluating the treatment effect under the assumption that participants in both the test and control groups with missing outcome data have a similar outcome profile as those with an identical history in the control group. We develop a robust framework to handle non-normal outcomes under CBI without imposing any parametric modeling assumptions. Under the proposed framework, sequential weighted robust regressions are applied to protect the constructed imputation model against non-normality in the covariates and the response variables. Accompanied by the subsequent mean imputation and robust model analysis, the resulting ATE estimator has good theoretical properties in terms of consistency and asymptotic normality. Moreover, our proposed method guarantees the analysis model robust-ness of the ATE estimation in the sense that its asymptotic results remain intact even when the analysis model is misspecified. The superiority of the proposed robust method is demonstrated by comprehensive simulation studies and an AIDS clinical trial data application.

11.
Aggress Behav ; 50(3): e22158, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38785112

RESUMO

Green spaces, integral to natural environments, have been extensively studied for their positive impact on mental health, yet their influence on social behavior, particularly aggression, is less explored. While prior research has predominantly emphasized the effects of actively engaging with nature, the significant role of passive nature exposure-a more common daily occurrence-has often been overlooked. We conducted two studies to explore the influence of passive green space exposure on aggression and the mediating effect of the sense of control. Study 1 (N = 240) utilized a cross-sectional survey to assess the relationship between passive green space exposure, sense of control, and aggression. Study 2 (N = 260) employed a single-factor between-subjects experimental design to further explore these relationships in a controlled environment. The results from both studies indicated that passive green space exposure is negatively related to aggression, and that this relationship is partially mediated by an increased sense of control. Specifically, passive green space exposure was found to negatively predict aggression by bolstering individuals' sense of control. These findings underscore the potential of enhancing the sense of control through environmental factors like green spaces as an effective strategy to reduce aggression. This study enriches our understanding of the broader impacts of green spaces, extending beyond mental health to include social behaviors. We discussed both the theoretical and practical implications of our findings, highlighting how urban planning and environmental design can incorporate green spaces to foster community well-being and mitigate aggressive behaviors.


Assuntos
Agressão , Humanos , Agressão/psicologia , Masculino , Feminino , Adulto , Adulto Jovem , Estudos Transversais , Parques Recreativos , Adolescente , Pessoa de Meia-Idade , Controle Interno-Externo
12.
Am J Physiol Cell Physiol ; 326(6): C1563-C1572, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38586879

RESUMO

Atherosclerosis is an inflammatory disease of blood vessels involving the immune system. Natural killer T (NKT) cells, as crucial components of the innate and acquired immune systems, play critical roles in the development of atherosclerosis. However, the mechanism and clinical relevance of NKT cells in early atherosclerosis are largely unclear. The study investigated the mechanism influencing NKT cell function in apoE deficiency-induced early atherosclerosis. Our findings demonstrated that there were higher populations of NKT cells and interferon-gamma (IFN-γ)-producing NKT cells in the peripheral blood of patients with hyperlipidemia and in the aorta, blood, spleen, and bone marrow of early atherosclerotic mice compared with the control groups. Moreover, we discovered that the infiltration of CD80+ macrophages and CD1d expression on CD80+ macrophages in atherosclerotic mice climbed remarkably. CD1d expression increased in CD80+ macrophages stimulated by oxidized low-density lipoprotein (ox-LDL) ex vivo and in vitro. Ex vivo coculture of macrophages with NKT cells revealed that ox-LDL-induced CD80+ macrophages presented lipid antigen α-Galcer (alpha-galactosylceramide) to NKT cells via CD1d, enabling NKT cells to express more IFN-γ. Furthermore, a greater proportion of CD1d+ monocytes and CD1d+CD80+ monocytes were found in peripheral blood of hyperlipidemic patients compared with that of healthy donors. Positive correlations were found between CD1d+CD80+ monocytes and NKT cells or IFN-γ+ NKT cells in hyperlipidemic patients. Our findings illustrated that CD80+ macrophages stimulated NKT cells to secrete IFN-γ via CD1d-presenting α-Galcer, which may accelerate the progression of early atherosclerosis. Inhibiting lipid antigen presentation by CD80+ macrophages to NKT cells may be a promising immune target for the treatment of early atherosclerosis.NEW & NOTEWORTHY This work proposed the ox-LDL-CD80+ monocyte/macrophage-CD1d-NKT cell-IFN-γ axis in the progression of atherosclerosis. The proinflammatory IFN-γ+ NKT cells are closely related to CD1d+CD80+ monocytes in hyperlipidemic patients. Inhibiting CD80+ macrophages to present lipid antigens to NKT cells through CD1d blocking may be a new therapeutic target for atherosclerosis.


Assuntos
Antígenos CD1d , Aterosclerose , Antígeno B7-1 , Hiperlipidemias , Lipoproteínas LDL , Macrófagos , Células T Matadoras Naturais , Animais , Humanos , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Antígenos CD1d/metabolismo , Antígenos CD1d/imunologia , Antígenos CD1d/genética , Aterosclerose/imunologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Hiperlipidemias/imunologia , Hiperlipidemias/metabolismo , Lipoproteínas LDL/imunologia , Lipoproteínas LDL/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Antígeno B7-1/metabolismo , Antígeno B7-1/imunologia , Interferon gama/metabolismo , Interferon gama/imunologia , Camundongos Endogâmicos C57BL , Feminino , Pessoa de Meia-Idade
13.
Physiol Plant ; 176(2): e14305, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659134

RESUMO

High night temperature stress is one of the main environmental factors affecting rice yield and quality. More and more evidence shows that microRNA (miRNA) plays an important role in various abiotic stresses. However, the molecular network of miRNA regulation on rice tolerance to high night temperatures remains unclear. Here, small RNA, transcriptome and degradome sequencing were integrated to identify differentially expressed miRNAs, genes, and key miRNA-target gene pairs in rice heat-sensitive and heat-tolerant lines at the filling stage suffering from high night temperature stress. It was discovered that there were notable differences in the relative expression of 102 miRNAs between the two rice lines under stress. Meanwhile, 5263 and 5405 mRNAs were differentially expressed in the heat-sensitive line and heat-tolerant line, and functional enrichment analysis revealed that these genes were involved in heat-related processes and pathways. The miRNAs-mRNAs target relationship was further verified by degradome sequencing. Eventually, 49 miRNAs-222 mRNAs target pairs with reverse expression patterns showed significant relative expression changes between the heat-tolerant and the heat-sensitive line, being suggested to be responsible for the heat tolerance difference of these two rice lines. Functional analysis of these 222 mRNA transcripts showed that high night temperature-responsive miRNAs targeted these mRNAs involved in many heat-related biological processes, such as transcription regulation, chloroplast regulation, mitochondrion regulation, protein folding, hormone regulation and redox process. This study identified possible miRNA-mRNA regulation relationships in response to high night temperature stress in rice and potentially contributed to heat resistance breeding of rice in the future.


Assuntos
Regulação da Expressão Gênica de Plantas , MicroRNAs , Oryza , Oryza/genética , Oryza/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Estresse Fisiológico/genética , Temperatura Alta , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , Transcriptoma/genética , Perfilação da Expressão Gênica , Resposta ao Choque Térmico/genética
14.
mSystems ; 9(4): e0105523, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38501864

RESUMO

Plant-associated diazotrophs strongly relate to plant nitrogen (N) supply and growth. However, our knowledge of diazotrophic community assembly and microbial N metabolism in plant microbiomes is largely limited. Here we examined the assembly and temporal dynamics of diazotrophic communities across multiple compartments (soils, epiphytic and endophytic niches of root and leaf, and grain) of three cereal crops (maize, wheat, and barley) and identified the potential N-cycling pathways in phylloplane microbiomes. Our results demonstrated that the microbial species pool, influenced by site-specific environmental factors (e.g., edaphic factors), had a stronger effect than host selection (i.e., plant species and developmental stage) in shaping diazotrophic communities across the soil-plant continuum. Crop diazotrophic communities were dominated by a few taxa (~0.7% of diazotrophic phylotypes) which were mainly affiliated with Methylobacterium, Azospirillum, Bradyrhizobium, and Rhizobium. Furthermore, eight dominant taxa belonging to Azospirillum and Methylobacterium were identified as keystone diazotrophic taxa for three crops and were potentially associated with microbial network stability and crop yields. Metagenomic binning recovered 58 metagenome-assembled genomes (MAGs) from the phylloplane, and the majority of them were identified as novel species (37 MAGs) and harbored genes potentially related to multiple N metabolism processes (e.g., nitrate reduction). Notably, for the first time, a high-quality MAG harboring genes involved in the complete denitrification process was recovered in the phylloplane and showed high identity to Pseudomonas mendocina. Overall, these findings significantly expand our understanding of ecological drivers of crop diazotrophs and provide new insights into the potential microbial N metabolism in the phyllosphere.IMPORTANCEPlants harbor diverse nitrogen-fixing microorganisms (i.e., diazotrophic communities) in both belowground and aboveground tissues, which play a vital role in plant nitrogen supply and growth promotion. Understanding the assembly and temporal dynamics of crop diazotrophic communities is a prerequisite for harnessing them to promote plant growth. In this study, we show that the site-specific microbial species pool largely shapes the structure of diazotrophic communities in the leaves and roots of three cereal crops. We further identify keystone diazotrophic taxa in crop microbiomes and characterize potential microbial N metabolism pathways in the phyllosphere, which provides essential information for developing microbiome-based tools in future sustainable agricultural production.


Assuntos
Microbiota , Microbiota/genética , Agricultura , Solo/química , Nitrogênio/análise , Produtos Agrícolas/metabolismo , Desenvolvimento Vegetal
15.
JCI Insight ; 9(8)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451736

RESUMO

Accumulation of sphingolipids, especially sphingosines, in the lysosomes is a key driver of several lysosomal storage diseases. The transport mechanism for sphingolipids from the lysosome remains unclear. Here, we identified SPNS1, which shares the highest homology to SPNS2, a sphingosine-1-phosphate (S1P) transporter, functions as a transporter for lysolipids from the lysosome. We generated Spns1-KO cells and mice and employed lipidomic and metabolomic approaches to reveal SPNS1 ligand identity. Global KO of Spns1 caused embryonic lethality between E12.5 and E13.5 and an accumulation of sphingosine, lysophosphatidylcholines (LPC), and lysophosphatidylethanolamines (LPE) in the fetal livers. Similarly, metabolomic analysis of livers from postnatal Spns1-KO mice presented an accumulation of sphingosines and lysoglycerophospholipids including LPC and LPE. Subsequently, biochemical assays showed that SPNS1 is required for LPC and sphingosine release from lysosomes. The accumulation of these lysolipids in the lysosomes of Spns1-KO mice affected liver functions and altered the PI3K/AKT signaling pathway. Furthermore, we identified 3 human siblings with a homozygous variant in the SPNS1 gene. These patients suffer from developmental delay, neurological impairment, intellectual disability, and cerebellar hypoplasia. These results reveal a critical role of SPNS1 as a promiscuous lysolipid transporter in the lysosomes and link its physiological functions with lysosomal storage diseases.


Assuntos
Modelos Animais de Doenças , Doenças por Armazenamento dos Lisossomos , Lisossomos , Camundongos Knockout , Animais , Feminino , Humanos , Masculino , Camundongos , Fígado/metabolismo , Lisofosfolipídeos/metabolismo , Doenças por Armazenamento dos Lisossomos/metabolismo , Doenças por Armazenamento dos Lisossomos/genética , Doenças por Armazenamento dos Lisossomos/patologia , Lisossomos/metabolismo , Esfingolipídeos/metabolismo , Esfingosina/análogos & derivados , Esfingosina/metabolismo
16.
J Exp Child Psychol ; 242: 105907, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38513328

RESUMO

Intuitive statistical inferences refer to making inferences about uncertain events based on limited probabilistic information, which is crucial for both human and non-human species' survival and reproduction. Previous research found that 7- and 8-year-old children failed in intuitive statistical inference tasks after heuristic strategies had been controlled. However, few studies systematically explored children's heuristic strategies of intuitive statistical inferences and their potential numerical underpinnings. In the current research, Experiment 1 (N = 81) examined 7- to 10-year-olds' use of different types of heuristic strategies; results revealed that children relied more on focusing on the absolute number strategy. Experiment 2 (N = 99) and Experiment 3 (N = 94) added continuous-format stimuli to examine whether 7- and 8-year-olds could make genuine intuitive statistical inferences instead of heuristics. Results revealed that both 7- and 8-year-olds and 9- and 10-year-olds performed better in intuitive statistical inference tasks with continuous-format stimuli, even after focusing on the absolute number strategy had been controlled. The results across the three experiments preliminarily hinted that the ratio processing system might rely on the approximate number system. Future research could clarify what specific numerical processing mechanism may be used and how it might support children's statistical intuitions.


Assuntos
Heurística , Intuição , Humanos , Incerteza
17.
J Environ Manage ; 355: 120504, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38447513

RESUMO

Ammonia-oxidation process directly contribute to soil nitrous oxide (N2O) emissions in agricultural soils. However, taxonomy of the key nitrifiers (within ammonia oxidising bacteria (AOB), archaea (AOA) and complete ammonia oxidisers (comammox Nitrospira)) responsible for substantial N2O emissions in agricultural soils is unknown, as is their regulation by soil biotic and abiotic factors. In this study, cumulative N2O emissions, nitrification rates, abundance and community structure of nitrifiers were investigated in 16 agricultural soils from major crop production regions of China using microcosm experiments with amended nitrogen (N) supplemented or not with a nitrification inhibitor (nitrapyrin). Key nitrifier groups involved in N2O emissions were identified by comparative analyses of the different treatments, combining sequencing and random forest analyses. Soil cumulative N2O emissions significantly increased with soil pH in all agricultural soils. However, they decreased with soil organic carbon (SOC) in alkaline soils. Nitrapyrin significantly inhibited soil cumulative N2O emissions and AOB growth, with a significant inhibition of the AOB Nitrosospira cluster 3a.2 (D11) abundance. One Nitrosospira multiformis-like OTU phylotype (OTU34), which was classified within the AOB Nitrosospira cluster 3a.2 (D11), had the greatest importance on cumulative N2O emissions and its growth significantly depended on soil pH and SOC contents, with higher growth at high pH and low SOC conditions. Collectively, our results demonstrate that alkaline soils with low SOC contents have high N2O emissions, which were mainly driven by AOB Nitrosospira cluster 3a.2 (D11). Nitrapyrin can efficiently reduce nitrification-related N2O emissions by inhibiting the activity of AOB Nitrosospira cluster 3a.2 (D11). This study advances our understanding of key nitrifiers responsible for high N2O emissions in agricultural soils and their controlling factors, and provides vital knowledge for N2O emission mitigation in agricultural ecosystems.


Assuntos
Ecossistema , Solo , Solo/química , Amônia/química , Carbono , Oxirredução , Archaea , Nitrificação , Microbiologia do Solo
18.
Microb Biotechnol ; 17(3): e14435, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38465781

RESUMO

The use of microbial inoculant is a promising strategy to improve plant health, but their efficiency often faces challenges due to difficulties in successful microbial colonization in soil environments. To this end, the application of biostimulation products derived from microbes is expected to resolve these barriers via direct interactions with plants or soil pathogens. However, their effectiveness and mechanisms for promoting plant growth and disease resistance remain elusive. In this study, we showed that root irrigation with the extracts of Streptomyces ahygroscopicus strain 769 (S769) solid fermentation products significantly reduced watermelon Fusarium wilt disease incidence by 30% and increased the plant biomass by 150% at a fruiting stage in a continuous cropping field. S769 treatment led to substantial changes in both bacterial and fungal community compositions, and induced a highly interconnected microbial association network in the rhizosphere. The root transcriptome analysis further suggested that S769 treatment significantly improved the expression of the MAPK signalling pathway, plant hormone signal transduction and plant-pathogen interactions, particular those genes related to PR-1 and ethylene, as well as genes associated with auxin production and reception. Together, our study provides mechanistic and empirical evidences for the biostimulation products benefiting plant health through coordinating plant and rhizosphere microbiome interaction.


Assuntos
Citrullus , Fusarium , Microbiota , Citrullus/genética , Citrullus/microbiologia , Rizosfera , Transcriptoma , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Microbiologia do Solo , Solo , Raízes de Plantas/microbiologia
19.
J Med Virol ; 96(3): e29544, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38511577

RESUMO

The impact of SARS-CoV-2 infection shortly after vaccination on vaccine-induced immunity is unknown, which is also one of the concerns for some vaccinees during the pandemic. Here, based on a cohort of individuals who encountered BA.5 infection within 8 days after receiving the fourth dose of a bivalent mRNA vaccine, preceded by three doses of inactivated vaccines, we show that booster mRNA vaccination provided 48% protection efficacy against symptomatic infections. At Day 7 postvaccination, the level of neutralizing antibodies (Nabs) against WT and BA.5 strains in the uninfected group trended higher than those in the symptomatic infection group. Moreover, there were greater variations in Nabs levels and a significant decrease in virus-specific CD4+ T cell response observed in the symptomatic infection group. However, symptomatic BA.5 infection significantly increased Nab levels against XBB.1.9.1 and BA.5 (symptomatic > asymptomatic > uninfected group) at Day 10 and resulted in a more gradual decrease in Nabs against BA.5 compared to the uninfected group at Day 90. Our data suggest that BA.5 infection might hinder the early generation of Nabs and the recall of the CD4+ T cell response but strengthens the Nab and virus-specific T cell response in the later phase. Our data confirmed that infection can enhance host immunity regardless of the short interval between vaccination and infection and alleviate concerns about infections shortly after vaccination, which provides valuable guidance for developing future vaccine administration strategies.


Assuntos
Anticorpos Neutralizantes , Vacinação , Humanos , Imunização Secundária , RNA Mensageiro/genética , Vacinas Combinadas , Anticorpos Antivirais
20.
Hum Cell ; 37(3): 752-767, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38536633

RESUMO

In recent years, abnormal m6A alteration in hepatocellular carcinoma (HCC) has been a focus on investigating the biological implications. In this study, our objective is to determine whether m6A modification contributes to the progression of HBV-related HCC. To achieve this, we employed a random forest model to screen top 8 characteristic m6A regulators from 19 candidate genes. Subsequently, we developed a nomogram model that utilizes these 8 characteristic m6A regulators to predict the prevalence of HBV-related HCC. According to decision curve analysis, patients may benefit from the nomogram model. The clinical impact curves exhibited a robust predictive capability of the nomogram models. Additionally, consensus molecular subtyping was employed to identify m6A modification patterns and m6A-related gene signature. The quantification of immune cell subsets was accomplished through the implementation of ssGSEA algorithms. PCA algorithms were developed to compute the m6A score for individual tumors. Two distinct m6A modification patterns, namely cluster A and cluster B, exhibited significant correlations with distinct immune infiltration patterns and biological pathways. Notably, patients belonging to cluster B demonstrated higher m6A scores compared to those in cluster A, as determined by the m6A score metric. Furthermore, the expression of IGFBP3 proteins was validated through immunofluorescence, revealing their pronounced lower expression in tumor tissues. In summary, our study underscores the importance of m6A modification in the advancement of HBV-related HCC. This research has the potential to yield novel prognostic biomarkers and therapeutic targets for the identification of HBV-related HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Vírus da Hepatite B/genética , Metilação de RNA , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Algoritmos
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