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1.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(4): 610-618, 2024 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-39223026

RESUMO

Immune checkpoint inhibitors have shown remarkable benefits in the treatment of solid tumors,while the occurrence of atypical response patterns and immune-related adverse events during treatment challenges the accuracy of therapeutic evaluation.Medical imaging is crucial for the evaluation of immunotherapy.It enables the assessment of treatment efficacy via both morphological and functional ways and offers unique a predictive value when being combined with artificial intelligence.Here we review the recent research progress in imaging-based evaluation of solid tumors treated with immune checkpoint inhibitors.


Assuntos
Inibidores de Checkpoint Imunológico , Imunoterapia , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos , Inteligência Artificial
2.
Artigo em Inglês | MEDLINE | ID: mdl-39236129

RESUMO

In this paper, we propose an effective plug-and-play module called structural relation network (SRN) to model structural dependencies in 3D point clouds for feature representation. Existing network architectures such as PointNet++ and RS-CNN capture local structures individually and ignore the inner interactions between different sub-clouds. Motivated by the fact that structural relation modeling plays critical roles for humans to understand 3D objects, our SRN exploits local information by modeling structural relations in 3D spaces. For a given sub-cloud of point sets, SRN firstly extracts its geometrical and locational relations with the other sub-clouds and maps them into the embedding space, then aggregates both relational features with the other sub-clouds. As the variation of semantics embedded in different sub-clouds is ignored by SRN, we further extend SRN to enable dynamic message passing between different sub-clouds. We propose a graph-based structural relation network (GSRN) where sub-clouds and their pairwise relations are modeled as nodes and edges respectively, so that the node features are updated by the messages along the edges. Since the node features might not be well preserved when acquiring the global representation, we propose a Combined Entropy Readout (CER) function to adaptively aggregate them into the holistic representation, so that GSRN simultaneously models the local-local and local-global region-wise interaction. The proposed SRN and GSRN modules are simple, interpretable, and do not require any additional supervision signals, which can be easily equipped with the existing networks. Experimental results on the benchmark datasets (ScanObjectNN, ModelNet40, ShapeNet Part, S3DIS, ScanNet and SUN-RGBD) indicate promising boosts on the tasks of 3D point cloud classification, segmentation and object detection.

3.
PhytoKeys ; 246: 27-42, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39239322

RESUMO

A new species of the firmoss from China, Huperziacrassifolia sp. nov., is described and illustrated based on morphological characters and molecular evidence. The new species resembles species associated with the H.javanica complex, in particular H.javanica based on leaf shape and serrations, but can be easily distinguished by elliptic lanceolate and thick coriaceous leaves, well differentiated seasonal constriction zones, and reflexed leaf margins when get dried. Phylogenomic reconstruction using whole chloroplast genome sequences recovered H.crassifolia as sister to H.sutchueniana and only distantly related to morphological similar species H.javanica, H.nanlingensis, and H.serrata. The genome size 2C = 17.2 pg indicated the new species to be a tetraploid, whereas diploid H.javanica had a genome size of 8.7 pg. Morphological characters, distribution, and conservation status of the new species are also presented.

4.
Heliyon ; 10(16): e36125, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39229516

RESUMO

Background: Idiopathic pulmonary fibrosis (IPF) is an irreversible lung disease with unclear pathological mechanisms. In this study, we utilized bidirectional Mendelian randomization (MR) to analyze the relationship between serum metabolites and IPF, and conducted metabolic pathway analysis. Aim: To determine the causal relationship between serum metabolites and IPF using MR analysis. Methods: A two-sample MR analysis was conducted to evaluate the causal relationship between 824 serum metabolites and IPF. The inverse variance weighted (IVW) method was used to estimate the causal relationship between exposure and results. Sensitivity analysis was conducted using MR Egger, weighted median, and maximum likelihood to eliminate pleiotropy. Additionally, metabolic pathway analysis was conducted to identify potential metabolic pathways. Results: We identified 12 serum metabolites (6 risks and 6 protective) associated with IPF from 824 metabolites. Among them, 11 were known and 1 was unknown. 1-Eicosatrienoylglycophorophospholine and 1-myristoylglycophorophospholine were bidirectional MR positive factors, with 1-myristoylglycophorophospholine being a risk factor (1.0013, 1.0097) and 1-eicosatrienoylglycophorine being a protective factor (0.9914, 0.9990). The four lipids (1-linoleoylglycerophoethanolamine*, total cholesterol in large high-density lipoprotein [HDL], cholesterol esters in very large HDL, and phospholipids in very large HDL) and one NA metabolite (degree of unsaturation) were included in the known hazardous metabolites. The known protective metabolites included three types of lipids (carnitine, 1-linoleoylglycerophoethanolamine*, and 1-eicosatrienoylglycerophophophorine), one amino acid (hypoxanthine), and two unknown metabolites (the ratio of omega-6 fatty acids to omega-3 fatty acids, and the ratio of photoshopids to total lipids ratio in chylomicrons and extremely large very low-density lipoprotein [VLDL]). Moreover, sn-Glycerol 3-phosphate and 1-Acyl-sn-glycero-3-phosphocline were found to be involved in the pathogenesis of IPF through metabolic pathways such as Glycerolide metabolism and Glycerophospholipid metabolism. Conclusion: Our study identified 6 causal risks and 6 protective serum metabolites associated with IPF. Additionally, 2 metabolites were found to be involved in the pathogenesis of IPF through metabolic pathways, providing a new perspective for further understanding the metabolic pathway and the pathogenesis of IPF.

5.
Vet Comp Oncol ; 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221701

RESUMO

Canine mammary gland tumour (CMT) is the most common spontaneous tumour in intact female dogs and often exhibits metastases. Auranofin (AF) is a gold complex used for treating rheumatism. The excellent anti-tumour ability of AF has been demonstrated in various types of human and canine tumours. In this study, five CMT cell lines (CIPp, CMT-7364, CHMp, CIPm and CTBp) and three CMT primary cells (G7894, L1883 and L6783) were used to explore the anti-tumour effect of AF on CMT. Two CMT cell lines (CIPp and CMT-7364) were used to search the underlying mechanism of the effect of AF on CMT. The results showed that AF inhibited the growth, migration, invasion, and colony formation abilities of CMT cells. Additionally, the growth of CMT in a 3D cell culture model was effectively suppressed by AF. Furthermore, AF induced cell apoptosis of CMT cells via the PI3K/AKT pathway. In conclusion, AF effectively induces CMT apoptosis by regulating the PI3K/AKT pathway, indicating that AF should be explored as a potential CMT treatment in future studies.

6.
Chem Commun (Camb) ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225283

RESUMO

A novel selenium dioxide promoted selenylation/cyclization of leucosceptrane sesterterpenoids was reported. Two types of leucosceptrane derivatives with different valence states of selenium atoms (Se2+ and Se4+) were obtained. The mechanisms of these two processes were proposed, and the selenium-containing derivates may serve as intermediates of Riley oxidation that could be trapped with appropriate substrates. Immunosuppressive activity screening revealed that 10 and 11 had obvious inhibitory effects on IFN-γ production, with IC50 values of 5.29 and 17.60 µM, respectively, which were more active than their precursor leucosceptroid A.

7.
Biotechnol J ; 19(8): e2400203, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39115336

RESUMO

Through iterative rounds of mutation and selection, proteins can be engineered to enhance their desired biological functions. Nevertheless, identifying optimal mutation sites for directed evolution remains challenging due to the vastness of the protein sequence landscape and the epistatic mutational effects across residues. To address this challenge, we introduce MLSmut, a deep learning-based approach that leverages multi-level structural features of proteins. MLSmut extracts salient information from protein co-evolution, sequence semantics, and geometric features to predict the mutational effect. Extensive benchmark evaluations on 10 single-site and two multi-site deep mutation scanning datasets demonstrate that MLSmut surpasses existing methods in predicting mutational outcomes. To overcome the limited training data availability, we employ a two-stage training strategy: initial coarse-tuning on a large corpus of unlabeled protein data followed by fine-tuning on a curated dataset of 40-100 experimental measurements. This approach enables our model to achieve satisfactory performance on downstream protein prediction tasks. Importantly, our model holds the potential to predict the mutational effects of any protein sequence. Collectively, these findings suggest that our approach can substantially reduce the reliance on laborious wet lab experiments and deepen our understanding of the intricate relationships between mutations and protein function.


Assuntos
Aprendizado Profundo , Mutação , Proteínas , Proteínas/genética , Proteínas/química , Biologia Computacional/métodos , Bases de Dados de Proteínas , Engenharia de Proteínas/métodos
8.
J Inflamm Res ; 17: 5177-5195, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104909

RESUMO

Introduction: Both rheumatoid arthritis (RA) and rosacea represent common chronic systemic autoimmune conditions. Recent research indicates a heightened RA risk among individuals with rosacea. However, the molecular mechanisms linking these diseases remain largely unknown. This study aims to uncover shared molecular regulatory networks and immune cell infiltration patterns in both rosacea and RA. Methods: The gene expression profiles of RA (GSE12021, GSE55457), and the rosacea gene expression profile (GSE6591), were downloaded from Gene Expression Omnibus (GEO) databases, and obtained to screen differentially expressed genes (DEGs) by using "limma" package in R software. Various analyses including GO, KEGG, protein-protein interaction (PPI) network, and weighted gene co-expression network analyses (WGCNA) were conducted to explore potential biological functions and signaling pathways. CIBERSORT was used to assess the abundance of immune cells. Pearson coefficients were used to calculate the correlations between overlapped genes and the leukocyte gene signature matrix. Flow cytometry (FCM) analysis confirmed the most abundant immune cells detected in rheumatoid arthritis and rosacea. Receiver operator characteristic (ROC) analysis, enzyme-linked immunosorbent assay (ELISA), and qRT-PCR were used to confirm biomarkers and functions. Results: Two hundred seventy-seven co-expressed DEGs were identified from these datasets. Functional enrichment analysis indicated that these DEGs were associated with immune processes and chemokine-mediated signaling pathways. Fourteen and 17 hub genes overlapped between cytoHubba and WGCNA were identified in RA and rosacea, respectively. Macrophages and dendritic cells were RA and rosacea's most abundant immune cells, respectively. The ROC curves demonstrated potential diagnostic values of CXCL10 and CCL27, showing higher levels in the serum of patients with RA or rosacea, and suggesting possible regulation in the densities and functions of macrophages and dendritic cells from RA and rosacea, which were validated by FCM and qRT-PCR. Conclusion: Importantly, our findings may contribute to the scientific basis for biomarkers and therapeutic targets for patients with RA and rosacea in the future.

9.
CNS Neurosci Ther ; 30(8): e14896, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39107944

RESUMO

PURPOSE: To explore the microstate characteristics and underlying brain network activity of Ménière's disease (MD) patients based on high-density electroencephalography (EEG), elucidate the association between microstate dynamics and clinical manifestation, and explore the potential of EEG microstate features as future neurobiomarkers for MD. METHODS: Thirty-two patients diagnosed with MD and 29 healthy controls (HC) matched for demographic characteristics were included in the study. Dysfunction and subjective symptom severity were assessed by neuropsychological questionnaires, pure tone audiometry, and vestibular function tests. Resting-state EEG recordings were obtained using a 256-channel EEG system, and the electric field topographies were clustered into four dominant microstate classes (A, B, C, and D). The dynamic parameters of each microstate were analyzed and utilized as input for a support vector machine (SVM) classifier to identify significant microstate signatures associated with MD. The clinical significance was further explored through Spearman correlation analysis. RESULTS: MD patients exhibited an increased presence of microstate class C and a decreased frequency of transitions between microstate class A and B, as well as between class A and D. The transitions from microstate class A to C were also elevated. Further analysis revealed a positive correlation between equilibrium scores and the transitions from microstate class A to C under somatosensory challenging conditions. Conversely, transitions between class A and B were negatively correlated with vertigo symptoms. No significant correlations were detected between these characteristics and auditory test results or emotional scores. Utilizing the microstate features identified via sequential backward selection, the linear SVM classifier achieved a sensitivity of 86.21% and a specificity of 90.61% in distinguishing MD patients from HC. CONCLUSIONS: We identified several EEG microstate characteristics in MD patients that facilitate postural control yet exacerbate subjective symptoms, and effectively discriminate MD from HC. The microstate features may offer a new approach for optimizing cognitive compensation strategies and exploring potential neurobiological markers in MD.


Assuntos
Eletroencefalografia , Doença de Meniere , Humanos , Masculino , Feminino , Eletroencefalografia/métodos , Doença de Meniere/fisiopatologia , Doença de Meniere/diagnóstico , Doença de Meniere/psicologia , Pessoa de Meia-Idade , Adulto , Cognição/fisiologia , Adaptação Fisiológica/fisiologia , Máquina de Vetores de Suporte , Testes Neuropsicológicos , Idoso
10.
J Asian Nat Prod Res ; : 1-10, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120438

RESUMO

Four new homoisoflavonoids, 7-hydroxy-3-[hydroxy(4'-methoxyphenyl)methyl]-benzopyran-4-one (1), (3R)-7, 8-dihydroxy-3-(4'-methoxybenzyl)-chroman-4-one (2), 7-hydroxy-3-(2'-hydroxy-4'-methoxybenzyl)-chroman-4-one (3), and 7-hydroxy-3-(2'-hydroxy-4'-methoxybenzyl)-benzopyran-4-one (4), were isolated from the seeds of Caesalpinia pulcherrima. The structures of new compounds were elucidated by MS and NMR spectra. Their absolute configurations were assigned using electronic circular dichroism spectrum. Compounds 2 and 4 exhibited cytotoxic effects on MCF-7/TAM cells with the IC50 values of 101.4 ± 0.03 and 93.02 ± 0.03 µM, respectively.

11.
Biochim Biophys Acta Bioenerg ; 1865(4): 149503, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39153589

RESUMO

Spectral variations of light-harvesting (LH) proteins of purple photosynthetic bacteria provide insight into the molecular mechanisms underlying spectral tuning of circular bacteriochlorophyll (BChl) arrays, which play crucial roles in photoenergy conversion in these organisms. Here we investigate spectral changes of the Qy band of B850 BChl a in LH2 protein from purple sulfur bacterium Thermochromatium tepidum (tepidum-LH2) by detergents and Ca2+. The tepidum-LH2 solubilized with lauryl dimethylamine N-oxide and n-octyl-ß-D-glucoside (LH2LDAO and LH2OG, respectively) exhibited blue-shift of the B850 Qy band with hypochromism compared with the tepidum-LH2 solubilized with n-dodecyl-ß-D-maltoside (LH2DDM), resulting in the LH3-like spectral features. Resonance Raman spectroscopy indicated that this blue-shift was ascribable to the loss of hydrogen-bonding between the C3-acetyl group in B850 BChl a and the LH2 polypeptides. Ca2+ produced red-shift of the B850 Qy band in LH2LDAO by forming hydrogen-bond for the C3-acetyl group in B850 BChl a, probably due to a change in the microenvironmental structure around B850. Ca2+-induced red-shift was also observed in LH2OG although the B850 acetyl group is still free from hydrogen-bonding. Therefore, the Ca2+-induced B850 red-shift in LH2OG would originate from an electrostatic effect of Ca2+. The current results suggest that the B850 Qy band in tepidum-LH2 is primarily tuned by two mechanisms, namely the hydrogen-bonding of the B850 acetyl group and the electrostatic effect.

12.
Ecotoxicol Environ Saf ; 283: 116822, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39096686

RESUMO

Antimony (Sb) poses a significant ecological threat. This study combines biochemical, pathological, transcriptome, and metabolome analyses to assess the short-term (14-day) toxic impact of two Sb levels (25 mg/kg and 125 mg/kg) on earthworms (Eisenia fetida). Higher Sb concentration caused severe intestinal damage, elevated metallothionein (MT) levels, and reduced antioxidant capacity. Metabolome analysis identifies 404 and 1698 significantly differential metabolites in the two groups. Metabolites such as S(-)-cathinone, N-phenyl-1-naphthylamine, serotonin, 4-hydroxymandelonitrile, and 5-fluoropentylindole contributed to the metabolic responses to Sb stress. Transcriptome analysis shows increased chitin synthesis as a protective response, impacting amino sugar and nucleotide sugar metabolism for cell wall synthesis and damage repair. Integrated analysis indicated that 5 metabolite-gene pairs were found in two Sb levels and 11 enriched pathways were related to signal transduction, carbohydrate metabolism, immune system, amino acid metabolism, digestive system, and nervous system. Therefore, the integration of multiomics approaches enhanced our comprehension of the molecular mechanisms underlying the toxicity of Sb in E. fetida.

13.
Biochem Biophys Res Commun ; 735: 150487, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39096885

RESUMO

Spinal Cord Injury (SCI) is a significant neurological disorder that can result in severe motor and cognitive impairments. Neuronal regeneration and functional recovery are critical aspects of SCI treatment, with calcium signaling being a crucial indicator of neuronal excitability. In this study, we utilized a murine model to investigate the effects of targeted wireless electrical stimulation (ES) on neuronal activity following SCI. After establishing a complete SCI model in normal mice, flexible electrodes were implanted, and targeted wireless ES was administered to the injury site. We employed fiber-optic photometric in vivo calcium imaging to monitor calcium signals in pyramidal neurons within the CA3 region of the hippocampus and the M1 region of the primary motor cortex. The experimental results demonstrated a significant reduction in calcium signals in CA3 and M1 pyramidal neurons following SCI (reduced by 76 % and 59 %, in peak respectively). However, the application of targeted wireless ES led to a marked increase in calcium signals in these neurons (increased by 118 % and 69 %, in peak respectively), indicating a recovery of calcium activity. These observations suggest that wireless ES has a positive modulatory effect on the excitability of pyramidal neurons post-SCI. Understanding these mechanisms is crucial for developing therapeutic strategies aimed at enhancing neuronal recovery and functional restoration following spinal cord injuries.

14.
Int Immunopharmacol ; 141: 113016, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39182269

RESUMO

The accumulating evidence has made it clear that iron overload is a crucial mechanism in bone loss. Protocatechualdehyde (PCA) has also been used to prevent osteoporosis in recent years. Whether PCA can reverse the harmful effects of iron overload on bone mass in aged rats is still unknown. Therefore, this study aimed to assess the role of PCA in iron overload-induced bone loss in senile rats. In the aged rat model, we observed that iron overload affects bone metabolism and bone remodeling, manifested by bone loss and decreased bone mineral density. The administration of PCA effectively mitigated the detrimental effects caused by iron overload, and concomitant reduction in MDA serum levels and elevation of SOD were noted. In addition, PCA-treated rats were observed to have significantly increased bone mass and elevated expression of SIRT3,BMP2,SOD2 and reduced expression of TNF-α in bone tissue. We also observed that PCA was able to reduce oxidative stress and inflammation and restore the imbalance in bone metabolism. When MC3T3-E1 and RAW264.7 cells induced osteoblast and osteoclasts differentiation, PCA intervention could significantly recover the restriction of osteogenic differentiation and up-regulation of osteoclast differentiation treated by iron overload. Further, by detecting changes in ROS, SOD, MDA, expression of SIRT3 and mitochondrial membrane potentials, we confirm that the damage caused to cells by iron overload is associated with decreased SIRT3 activity, and that 3-TYP have similar effects on oxidative stress caused by FAC. In conclusion, PCA can resist iron overload-induced bone damage by improving SIRT3 activity, anti-inflammatory and anti-oxidative stress.

15.
Int J Mol Sci ; 25(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39125685

RESUMO

Transcription factors (TFs) are crucial pre-transcriptional regulatory mechanisms that can modulate the expression of downstream genes by binding to their promoter regions. DOF (DNA binding with One Finger) proteins are a unique class of TFs with extensive roles in plant growth and development. Our previous research indicated that iron content varies among bamboo leaves of different colors. However, to our knowledge, genes related to iron metabolism pathways in bamboo species have not yet been studied. Therefore, in the current study, we identified iron metabolism related (IMR) genes in bamboo and determined the TFs that significantly influence them. Among these, DOFs were found to have widespread effects and potentially significant impacts on their expression. We identified specific DOF members in Dendrocalamus latiflorus with binding abilities through homology with Arabidopsis DOF proteins, and established connections between some of these members and IMR genes using RNA-seq data. Additionally, molecular docking confirmed the binding interactions between these DlDOFs and the DOF binding sites in the promoter regions of IMR genes. The co-expression relationship between the two gene sets was further validated using q-PCR experiments. This study paves the way for research into iron metabolism pathways in bamboo and lays the foundation for understanding the role of DOF TFs in D. latiflorus.


Assuntos
Regulação da Expressão Gênica de Plantas , Ferro , Folhas de Planta , Proteínas de Plantas , Fatores de Transcrição , Folhas de Planta/metabolismo , Folhas de Planta/genética , Ferro/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas , Simulação de Acoplamento Molecular , Poaceae/genética , Poaceae/metabolismo
16.
Nanomedicine (Lond) ; : 1-12, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109508

RESUMO

Aim: We synthesized MgO NPs via sol-gel reaction and investigated them as carriers to deliver Mg2+ to the affected joint for osteoarthritis (OA). Materials & methods: The physicochemical properties of samples were characterized by transmission electron microscope (TEM), dynamic light scattering (DLS) and x-ray diffraction (XRD). The release of Mg2+ was monitored by ICP-MS. The potential cytotoxicity was evaluated using MTT assay. The efficacy and biosafety were evaluated in a rabbit OA model. Results: MgO NPs can prolong the Mg2+ release time from 0.5 h to 12 h. No significant cytotoxicity was observed when concentrations below 250 µg/ml. Intra-articular samples could effectively alleviate the degeneration and destruction of the cartilage. Conclusion: this study demonstrates the potential of MgO NPs as a safe and effective treatment of OA. Simultaneously, the size of the particles may play a significant role in influencing the therapeutic outcome.


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17.
BMC Microbiol ; 24(1): 294, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107680

RESUMO

The colonization of alien plants in new habitats is typically facilitated by microorganisms present in the soil environment. However, the diversity and structure of the archaeal, bacterial, and fungal communities in the latitudinal spread of alien plants remain unclear. In this study, the rhizosphere and bulk soil of Chromolaena odorata were collected from five latitudes in Pu' er city, Yunnan Province, followed by amplicon sequencing of the soil archaeal, bacterial, and fungal communities. Alpha and beta diversity results revealed that the richness indices and the structures of the archaeal, bacterial, and fungal communities significantly differed along the latitudinal gradient. Additionally, significant differences were observed in the bacterial Shannon index, as well as in the structures of the bacterial and fungal communities between the rhizosphere and bulk soils. Due to the small spatial scale, trends of latitudinal variation in the archaeal, bacterial, and fungal communities were not pronounced. Total potassium, total phosphorus, available nitrogen, available potassium and total nitrogen were the important driving factors affecting the soil microbial community structure. Compared with those in bulk soil, co-occurrence networks in rhizosphere microbial networks presented lower complexity but greater modularity and positive connections. Among the main functional fungi, arbuscular mycorrhizae and soil saprotrophs were more abundant in the bulk soil. The significant differences in the soil microbes between rhizosphere and bulk soils further underscore the impact of C. odorata invasion on soil environments. The significant differences in the soil microbiota along latitudinal gradients, along with specific driving factors, demonstrate distinct nutrient preferences among archaea, bacteria, and fungi and indicate complex microbial responses to soil nutrient elements following the invasion of C. odorata.


Assuntos
Archaea , Bactérias , Chromolaena , Fungos , Microbiota , Rizosfera , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Chromolaena/microbiologia , Archaea/classificação , Archaea/genética , Archaea/isolamento & purificação , China , Espécies Introduzidas , Biodiversidade , Solo/química , Raízes de Plantas/microbiologia , Filogenia
18.
Food Chem ; 460(Pt 2): 140646, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39089018

RESUMO

The study aimed to mine and characterize novel antimicrobial peptides (AMPs) from the Shanxi aged vinegar microbiome. Utilizing machine learning techniques, AlphaFold2 structure prediction and molecular dynamics simulations, six novel AMPs were innovatively mined from 98,539 peptides based on metagenomic data, of which one peptide secreted by Lactobacillus (named La-AMP) was experimentally validated to have remarkable bactericidal effects against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) with high stability and no hemolytic activity. Scanning electron microscopy revealed that La-AMP caused irreversible damage to cell membranes of S. aureus and E. coli, a finding further confirmed by calcein-AM/propidium iodide staining. Additionally, La-AMP induced nucleic acid leakage and reactive oxygen species accumulation in bacterial cells. It was found to bind to DNA gyrase through salt bridges, hydrogen bonds, and hydrophobic interactions, ultimately inducing apoptosis. Thus, La-AMP exhibited encouraging promise as a valuable bioactive component for the development of natural preservatives.


Assuntos
Ácido Acético , Escherichia coli , Metagenômica , Simulação de Dinâmica Molecular , Staphylococcus aureus , Staphylococcus aureus/efeitos dos fármacos , Ácido Acético/química , Ácido Acético/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/metabolismo , Peptídeos Antimicrobianos/química , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/metabolismo , Peptídeos Antimicrobianos/genética , Antibacterianos/farmacologia , Antibacterianos/química , Microbiota , Testes de Sensibilidade Microbiana , Humanos , Lactobacillus/química , Lactobacillus/metabolismo
19.
RSC Adv ; 14(36): 26166-26175, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39161453

RESUMO

Promoting the Curie temperature (T C) and tunning the magnetocrystalline anisotropy energy (MAE) have been key issues with two-dimensional (2D) ferromagnetic (FM) materials. Here, the structural and magnetic properties of MnTe2/X (X = As, Sb and Bi) heterostructures are investigated through first-principles calculations. We reveal that monolayer MnTe2 weakly interacts with monolayer As or Sb through van der Waals (vdW) forces, but has strong covalent bonds with monolayer Bi, indicated by Bi-Te bond formation. The coupling of MnTe2 with these ß-phase group-VA semiconductor monolayers substantially modulates MAE, with MnTe2/As showing a shift to in-plane easy magnetization, and MnTe2/Sb exhibiting a large perpendicular MAE of 4.13 meV per cell. The formation of vdW heterostructures influence on Te spin-orbit coupling matrix elements markedly governs MAE. MnTe2/Bi also has an in-plane MAE, contributed by both Te and Bi atoms. Additionally, coupling MnTe2 with X significantly affects magnetic interactions. It is worth noting that the T C of MnTe2/Sb reaches 233.2 K, significantly larger than that of pure MnTe2. A large perpendicular MAE and a heightened T C makes MnTe2/Sb desired candidates for next-generation spintronic applications. Our work provides a way to modulate the magnetic properties of 2D FM materials.

20.
J Mol Neurosci ; 74(3): 79, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39162890

RESUMO

Diabetic neuropathic pain (DNP) is a diabetic complication that causes severe pain and deeply impacts the quality of the sufferer's daily life. Currently, contemporary clinical treatments for DNP generally exhibit a deficiency in effectiveness. Electroacupuncture (EA) is recognized as a highly effective and safe treatment for DNP with few side effects. Regrettably, the processes via which EA alleviates DNP are still poorly characterized. Transient receptor potential vanilloid 1 (TRPV1) and phosphorylated calcium/calmodulin-dependent protein kinase II (p-CaMKII) are overexpressed on spinal cord dorsal horn (SCDH) in DNP rats, and co-localization is observed between them. Capsazepine, a TRPV1 antagonist, effectively reduced nociceptive hypersensitivity and downregulated the overexpression of phosphorylated CaMKIIα in rats with DNP. Conversely, the CaMKII inhibitor KN-93 did not have any impact on TRPV1. EA alleviated heightened sensitivity to pain caused by nociceptive stimuli and downregulated the level of TRPV1, p-CaMKIIα, and phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB) in DNP rats. Intrathecal injection of capsaicin, on the other hand, reversed the above effects of EA. These findings indicated that the CaMKII/CREB pathway on SCDH is located downstream of TRPV1 and is affected by TRPV1. EA alleviates DNP through the TRPV1-mediated CaMKII/CREB pathway.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Neuropatias Diabéticas , Eletroacupuntura , Ratos Sprague-Dawley , Canais de Cátion TRPV , Animais , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/antagonistas & inibidores , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Eletroacupuntura/métodos , Ratos , Masculino , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Neuropatias Diabéticas/terapia , Neuropatias Diabéticas/metabolismo , Capsaicina/farmacologia , Capsaicina/análogos & derivados , Transdução de Sinais , Corno Dorsal da Medula Espinal/metabolismo , Benzenossulfonamidas , Benzilaminas
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