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1.
ACS Synth Biol ; 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140342

RESUMO

Outer membrane vesicles (OMVs) of Gram-negative bacteria play an essential role in cellular physiology. The underlying regulatory mechanism of OMV formation and its impact on extracellular electron transfer (EET) in the model exoelectrogenShewanella oneidensis MR-1 remain unclear and have not been reported. To explore the regulatory mechanism of OMV formation, we used the CRISPR-dCas9 gene repression technology to reduce the crosslink between the peptidoglycan (PG) layer and the outer membrane, thus promoting the OMV formation. We screened the target genes that were potentially beneficial to the outer membrane bulge, which were classified into two modules: PG integrity module (Module 1) and outer membrane component module (Module 2). We found that downregulation of the penicillin-binding protein-encoding gene pbpC for peptidoglycan integrity (Module 1) and the N-acetyl-d-mannosamine dehydrogenase-encoding gene wbpP involved in lipopolysaccharide synthesis (Module 2) exhibited the highest production of OMVs and enabled the highest output power density of 331.3 ± 1.2 and 363.8 ± 9.9 mW m-2, 6.33- and 6.96-fold higher than that of the wild-typeS. oneidensis MR-1 (52.3 ± 0.6 mW m-2), respectively. To elucidate the specific impacts of OMV formation on EET, OMVs were isolated and quantified for UV-visible spectroscopy and heme staining characterization. Our study showed that abundant outer membrane c-type cytochromes (c-Cyts) including MtrC and OmcA and periplasmic c-Cyts were exposed on the surface or inside of OMVs, which were the vital constituents responsible for EET. Meanwhile, we found that the overproduction of OMVs could facilitate biofilm formation and increase biofilm conductivity. To the best of our knowledge, this study is the first to explore the mechanism of OMV formation and its correlation with EET of S. oneidensis, which paves the way for further study of OMV-mediated EET.

2.
Phys Chem Chem Phys ; 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37194400

RESUMO

Silver nanowire (AgNW) networks have excellent optoelectronic properties and have important applications in various optoelectronic devices. However, the random distribution of AgNWs coated on the substrate will cause problems such as uneven resistance and high surface roughness, which will affect the properties of the film. In order to solve these problems, this paper adopts the method of directional arrangement of AgNWs to prepare conductive films, by mixing AgNW aqueous solution with hydroxypropyl methyl cellulose (HPMC) to prepare conductive ink, and then the AgNWs are oriented on the flexible substrate by using the shear force generated during the Mayer rod coating process. The multilayer crossed three-dimensional (3D) AgNW conductive network is prepared, achieving a sheet resistance of 12.9 Ω sq-1 and a transmittance of 92.2% (λ = 550 nm). In addition, the roughness RMS value of the layered and ordered AgNW/HPMC composite film is only 6.96 nm, which is much lower than that of the randomly arranged AgNW film (RMS = 19.8 nm), and the composite film also has excellent bending resistance and environmental stability. This adjustable coating method is simple to prepare and can realize the large-scale manufacturing of conductive films, which is important for the future development of flexible transparent conductive films.

3.
Hortic Res ; 10(5): uhad062, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37220556

RESUMO

Prunus pusilliflora is a wild cherry germplasm resource distributed mainly in Southwest China. Despite its ornamental and economic value, a high-quality assembled P. pusilliflora genome is unavailable, hindering our understanding of its genetic background, population diversity, and evolutionary processes. Here, we de novo assembled a chromosome-scale P. pusilliflora genome using Oxford Nanopore, Illumina, and chromosome conformation capture sequencing. The assembled genome size was 309.62 Mb, with 76 scaffolds anchored to eight pseudochromosomes. We predicted 33 035 protein-coding genes, functionally annotated 98.27% of them, and identified repetitive sequences covering 49.08% of the genome. We found that P. pusilliflora is closely related to Prunus serrulata and Prunus yedoensis, having diverged from them ~41.8 million years ago. A comparative genomic analysis revealed that P. pusilliflora has 643 expanded and 1128 contracted gene families. Furthermore, we found that P. pusilliflora is more resistant to Colletotrichum viniferum, Phytophthora capsici, and Pseudomonas syringae pv. tomato (Pst) DC3000 infections than cultivated Prunus avium. P. pusilliflora also has considerably more nucleotide-binding site-type resistance gene analogs than P. avium, which explains its stronger disease resistance. The cytochrome P450 and WRKY families of 263 and 61 proteins were divided into 42 and 8 subfamilies respectively in P. pusilliflora. Furthermore, 81 MADS-box genes were identified in P. pusilliflora, accompanying expansions of the SVP and AGL15 subfamilies and loss of the TM3 subfamily. Our assembly of a high-quality P. pusilliflora genome will be valuable for further research on cherries and molecular breeding.

4.
J Mater Chem B ; 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37222008

RESUMO

Protein glycosylation and phosphorylation are the two most important post-translational modifications, which play a vital role in physiological and pathological processes. Before the comprehensive characterization of glycoproteome/phosphoproteome through the mass spectrometry (MS) technique, it is necessary to perform a highly specific enrichment procedure because glycoproteins/phosphoproteins inherently occur in low abundances. Herein, we have reported a novel magnetic ß-cyclodextrin-based host-guest Ti-phenolic network material, focusing on the simultaneous enrichment of glycopeptides/phosphopeptides via hydrophilic interaction chromatography and immobilized metal ion chromatography. Ti ions and glutathione-derived adamantine were introduced by metal-phenolic interactions and host-guest interactions. The material possesses biocompatibility, good hydrophilicity, strong magnetic response, metal chelation effect, and demonstrates an excellent enrichment ability towards glycopeptides/phosphopeptides. Combined with MS detection, high sensitivity (0.035/0.01 fmol for IgG/ß-casein) and good reusability (6 times) were achieved. In addition, its outstanding specificity was validated in quantities as low as 500 : 1 : 1 for BSA : IgG : ß-casein (m/m/m). Benefiting from these merits, the adsorbent material was successfully used for the simultaneous enrichment of phosphopeptides/glycopeptides from human serum and HeLa cell lysate and can be expected to exhibit great applicability for precious and small amounts of biosamples in the study of glycoproteomics/phosphoproteomics.

5.
Small ; : e2303108, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37222117

RESUMO

Flexible solid-state Zn-ion batteries (ZIBs) have garnered considerable attention for next-generation power sources, but the corrosion, dendrite growth, and interfacial problems severely hinder their practical applications. Herein, a high-performance flexible solid-state ZIB with a unique heterostructure electrolyte is facilely fabricated through ultraviolet-assisted printing strategy. The solid polymer/hydrogel heterostructure matrix not only isolates water molecules and optimizes electric field distribution for dendrite-free anode, but also facilitates fast and in-depth Zn2+ transport in the cathode. The in situ ultraviolet-assisted printing creates cross-linked and well-bonded interfaces between the electrodes and the electrolyte, enabling low ionic transfer resistance and high mechanical stability. As a result, the heterostructure electrolyte based ZIB outperforms single-electrolyte based cells. It not only delivers a high capacity of 442.2 mAh g-1 with long cycling life of 900 cycles at 2 A g-1 , but also maintains stable operation under mechanical bending and high-pressure compression in a wide temperature range (-20 °C to 100 °C).

6.
Molecules ; 28(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37175112

RESUMO

Ulcerative colitis (UC) has attracted much attention for its negative influence on quality of life and increased risk of colorectal cancer. Chemical and biological drugs are currently the usual treatment for UC. These drugs always induce severe side effects, or patients might become resistant to these therapies. Therefore, new therapeutic options for UC are urgently needed. In this study, we discovered the inhibitory activity of the intestinal tryptophan metabolite indole-3-carboxaldehyde (3-IAld) in dextran sulfate sodium salt (DSS)-induced UC mice by targeting the TLR4/NF-κB/p38 signaling pathway. This compound effectively protected against colon length shortening and damage induced by DSS in the colon, notably reducing the severity of inflammation. The production of inflammatory factors of TNF-α, IL-6, and IL-1ß was significantly attenuated when treating with 3-IAld in vivo and vitro. This might be attributed to inhibition of the TLR4/NF-kB/p38 signaling pathway. Moreover, 3-IAld could up-regulate the expression of ZO-1 and Occludin in vivo and vitro. Meanwhile, liquid chromatography mass spectrometry (LC-MS) results showed that 3-IAld could balance the aspartate and glutamate metabolism and the lysine degradation metabolism in the serum of DSS-induced colitis mice. In conclusion, 3-IAld ameliorated the intestinal barrier dysfunction and inflammatory response in DSS-induced UC mice, balanced amino acid metabolism, and inhibited the activation of the TLR4/NF-kB/p38 signaling pathway, thereby protecting mice with colitis.


Assuntos
Colite Ulcerativa , Colite , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Triptofano/metabolismo , NF-kappa B/metabolismo , Receptor 4 Toll-Like/metabolismo , Qualidade de Vida , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/metabolismo , Colo/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Cloreto de Sódio/farmacologia , Cloreto de Sódio na Dieta , Sulfato de Dextrana/efeitos adversos , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
7.
Biotechnol Adv ; 66: 108170, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37148984

RESUMO

Electroactive biofilms (EABs) are electroactive microorganisms (EAMs) encased in conductive polymers that are secreted by EAMs and formed by the accumulation and cross-linking of extracellular polysaccharides, proteins, nucleic acids, lipids, and other components. EABs are present in the form of multicellular aggregates and play a crucial role in bioelectrochemical systems (BESs) for diverse applications, including biosensors, microbial fuel cells for renewable bioelectricity production and remediation of wastewaters, and microbial electrosynthesis of valuable chemicals. However, naturally occurred EABs are severely limited owing to their low electrical conductivity that seriously restrict the electron transfer efficiency and practical applications. In the recent decade, synthetic biology strategies have been adopted to elucidate the regulatory mechanisms of EABs, and to enhance the formation and electrical conductivity of EABs. Based on the formation of EABs and extracellular electron transfer (EET) mechanisms, the synthetic biology-based engineering strategies of EABs are summarized and reviewed as follows: (i) Engineering the structural components of EABs, including strengthening the synthesis and secretion of structural elements such as polysaccharides, eDNA, and structural proteins, to improve the formation of biofilms; (ii) Enhancing the electron transfer efficiency of EAMs, including optimizing the distribution of c-type cytochromes and conducting nanowire assembly to promote contact-based EET, and enhancing electron shuttles' biosynthesis and secretion to promote shuttle-mediated EET; (iii) Incorporating intracellular signaling molecules in EAMs, including quorum sensing systems, secondary messenger systems, and global regulatory systems, to increase the electron transfer flux in EABs. This review lays a foundation for the design and construction of EABs for diverse BESs applications.

8.
Cell Signal ; 108: 110725, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37230199

RESUMO

BACKGROUND: Both microRNA-21-5p (miR-21) and the tumor microenvironment, including hypoxia and cancer-associated fibroblasts (CAFs), play a vital role in head and neck squamous cell carcinoma (HNSCC), but whether there is an interaction and the specific regulatory mechanism between them in the process of metastasis is still unclear. In this study, we aimed to elucidate the connection and regulatory mechanism of miR-21, hypoxia, and CAFs in HNSCC metastasis. METHODS: The underlying mechanisms of hypoxia inducible factor 1 subunit alpha (HIF1α) regulating miR-21 transcription, promoting exosome secretion, CAFs activation, tumor invasion, and lymph node metastasis were determined through quantitative real-time PCR, immunoblotting, transwell, wound healing, immunofluorescence, ChIP, electron microscopy, nanoparticle tracking analysis, dual-luciferase reporter assay, co-culture model and xenografts experiments. RESULTS: MiR-21 promoted the invasion and metastasis of HNSCC in vitro and in vivo, whereas HIF1α knockdown inhibited these processes. HIF1α upregulated transcription of miR-21 and promoted the release of exosomes from HNSCC cells. Exosomes derived from hypoxic tumor cells were rich in miR-21, which induced NFs activation towards CAFs by targeting YOD1. Knockdown the expression level of miR-21 in CAFs prevented lymph node metastasis in HNSCC. CONCLUSION: Hypoxic tumor cell-derived exosomal miR-21 might be a therapeutic target to prevent or delay HNSCC invasion and metastasis.

9.
Bioresour Technol ; 379: 129067, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37080438

RESUMO

Hydrochars are promising sorbents for wastewater treatment. Herein, two acrylate-modified hydrochars (AMHC1 and AMHC2) were obtained by grafting acrylic acid on the surface of two hydrochars (MHC1 and MHC2 hydrothermally carbonized in water and acidic medium respectively) with free radical polymerization. Characterizations show that MHC2 is more prone to free radical polymerization than MHC1 does, and has higher carboxylate content after modification. The adsorption amounts of AMHC2 over methylene blue (MB) and Pb(II) are much higher than those of AMHC1. Pseudo-second-order kinetic and Langmuir isotherm equations well fit the Pb(II) and MB sorption data of AMHC2. The Pb(II) adsorptive mechanism is mainly inner-surface complexation accompanied by ion exchange and cation-π interaction. MB adsorption involves ion exchange, electrostatic interaction, H-bonding and π-π interaction. Hence, the one-step modification method of free radical polymerization under alkaline condition has great potential for preparing carboxylate-modified hydrochars to adsorb cationic pollutants.


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Azul de Metileno/análise , Chumbo , Adsorção , Poluentes Químicos da Água/análise , Acrilatos , Água , Cinética , Ácidos Carboxílicos , Concentração de Íons de Hidrogênio
10.
Proc Natl Acad Sci U S A ; 120(15): e2220704120, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37014860

RESUMO

The analysis of cell-free DNA (cfDNA) from plasma offers great promise for the earlier detection of cancer. At present, changes in DNA sequence, methylation, or copy number are the most sensitive ways to detect the presence of cancer. To further increase the sensitivity of such assays with limited amounts of sample, it would be useful to be able to evaluate the same template molecules for all these changes. Here, we report an approach, called MethylSaferSeqS, that achieves this goal, and can be applied to any standard library preparation method suitable for massively parallel sequencing. The innovative step was to copy both strands of each DNA-barcoded molecule with a primer that allows the subsequent separation of the original strands (retaining their 5-methylcytosine residues) from the copied strands (in which the 5-methylcytosine residues are replaced with unmodified cytosine residues). The epigenetic and genetic alterations present in the DNA molecules can then be obtained from the original and copied strands, respectively. We applied this approach to plasma from 265 individuals, including 198 with cancers of the pancreas, ovary, lung, and colon, and found the expected patterns of mutations, copy number alterations, and methylation. Furthermore, we could determine which original template DNA molecules were methylated and/or mutated. MethylSaferSeqS should be useful for addressing a variety of questions relating genetics and epigenetics.


Assuntos
Variações do Número de Cópias de DNA , Neoplasias , Feminino , Humanos , Metilação , 5-Metilcitosina , DNA/genética , Mutação , Neoplasias/genética , Metilação de DNA
11.
Ying Yong Sheng Tai Xue Bao ; 34(3): 751-760, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37087659

RESUMO

Ecological compensation plays an important role in maintaining ecosystem services and promoting regional green development. We built a regional horizontal ecological compensation model based on water resources pattern and insurance gain, and which was used to solve the problems of single compensation method and low compensation efficiency. Taking the Beijing-Tianjin-Hebei region as an example, we analyzed water footprint and water ecological carrying capacity from 2000 to 2019. The compensation subject and object and water footprint compensation amount were determined according to the input cost of ecological protection and allocation factor. Then, the insurance pricing model was introduced to determine ecological insurance premium rate. We calculated insurance compensation, ecological compensation standard and different types of ecosystem service value. Results showed that the whole region was at a state of water ecological deficit, with the agricultural water footprint accounting for 94.5%. From the perspective of the compensation subject and object, Beijing and Tianjin, as the compensation subject, needed to pay 0.402 billion yuan and 0.396 billion yuan (the amount of compensation) to Hebei Province each year. Hebei Province obtained a total of 0.228 billion yuan of ecological insurance with an insurance premium rate of 1.4%, and should receive an average annual ecological compensation standard of 0.81 billion yuan from Beijing and Tianjin. Hydrological regulation was the core ecosystem service in the region, with an average value of 187.974 billion yuan. It was of strategic significance to introduce ecological insurance mechanism to construct horizontal ecological compensation mechanism, improve ecosystem service function, and enhance the value of ecosystem services in the study area.


Assuntos
Ecossistema , Recursos Hídricos , Conservação dos Recursos Naturais , Pequim , Água , China
12.
World J Pediatr ; 2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37029331

RESUMO

BACKGROUND: Previous studies have linked gestational diabetes (GDM) with allergies in offspring. However, the effect of specific glucose metabolism metrics was not well characterized, and the role of polyunsaturated fatty acids (PUFAs), a modifier of metabolism and the immune system, was understudied. We aimed to investigate the association between maternal GDM and allergic diseases in children and the interaction between glucose metabolism and PUFAs on allergic outcomes. METHODS: This prospective cohort study included 706 mother-child dyads from Guangzhou, China. Maternal GDM was diagnosed via a 75-g oral glucose tolerance test (OGTT), and dietary PUFAs were assessed using a validated food frequency questionnaire. Allergic disease diagnoses and the age of onset were obtained from medical records of children within three years old. RESULTS: Approximately 19.4% of women had GDM, and 51.3% of children had any allergic diseases. GDM was positively associated with any allergic diseases (hazard ratio [HR] 1.40; 95% confidence interval (CI) 1.05-1.88) and eczema (HR 1.44; 95% CI 1.02-1.97). A unit increase in OGTT after two hours (OGTT-2 h) glucose was associated with an 11% (95% CI 2%-21%) higher risk of any allergic diseases and a 17% (95% CI 1-36%) higher risk of food allergy. The positive associations between OGTT-2 h glucose and any allergic diseases were strengthened with decreased dietary a-linolenic acid (ALA) and increased n-6 PUFAs, linoleic acid (LA), LA/ALA ratio, and n-6/n-3 PUFA ratio. CONCLUSIONS: Maternal GDM was adversely associated with early-life allergic diseases, especially eczema. We were the first to identify OGTT-2 h glucose to be more sensitive in inducing allergy risk and that dietary PUFAs might modify the associations.

13.
Trials ; 24(1): 266, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041561

RESUMO

BACKGROUND: Acute respiratory syndrome distress (ARDS) is a clinical common syndrome with high mortality. Electrical impedance tomography (EIT)-guided positive end-expiratory pressure (PEEP) titration can achieve the compromise between lung overdistension and collapse which may minimize ventilator-induced lung injury in these patients. However, the effect of EIT-guided PEEP titration on the clinical outcomes remains unknown. The objective of this trial is to investigate the effects of EIT-guided PEEP titration on the clinical outcomes for moderate or severe ARDS, compared to the low fraction of inspired oxygen (FiO2)-PEEP table. METHODS: This is a prospective, multicenter, single-blind, parallel-group, adaptive designed, randomized controlled trial (RCT) with intention-to-treat analysis. Adult patients with moderate to severe ARDS less than 72 h after diagnosis will be included in this study. Participants in the intervention group will receive PEEP titrated by EIT with a stepwise decrease PEEP trial, whereas participants in the control group will select PEEP based on the low FiO2-PEEP table. Other ventilator parameters will be set according to the ARDSNet strategy. Participants will be followed up until 28 days after enrollment. Three hundred seventy-six participants will be recruited based on a 15% decrease of 28-day mortality in the intervention group, with an interim analysis for sample size re-estimation and futility assessment being undertaken once 188 participants have been recruited. The primary outcome is 28-day mortality. The secondary outcomes include ventilator-free days and shock-free days at day 28, length of ICU and hospital stay, the rate of successful weaning, proportion requiring rescue therapies, compilations, respiratory variables, and Sequential Organ Failure Assessment (SOFA). DISCUSSION: As a heterogeneous syndrome, ARDS has different responses to treatment and further results in different clinical outcomes. PEEP selection will depend on the properties of patients and can be individually achieved by EIT. This study will be the largest randomized trial to investigate thoroughly the effect of individual PEEP titrated by EIT in moderate to severe ARDS patients to date. TRIAL REGISTRATION: ClinicalTrial.gov NCT05207202. First published on January 26, 2022.


Assuntos
Síndrome do Desconforto Respiratório do Recém-Nascido , Síndrome do Desconforto Respiratório , Adulto , Recém-Nascido , Humanos , Respiração com Pressão Positiva/efeitos adversos , Pulmão , Síndrome do Desconforto Respiratório/terapia , Prognóstico , Tomografia Computadorizada por Raios X , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
14.
Transl Lung Cancer Res ; 12(3): 510-529, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37057124

RESUMO

Background: Only a fraction of lung adenocarcinoma (LUAD) patients are eligible for immunotherapy. The identification of biomarkers for immunotherapy is crucial to improve patient outcomes. This study aims to systemically analyze LRP1B mutation and its association with the tumor immune microenvironment (TIME) and immunotherapy. Methods: A cohort of immune checkpoint inhibitors (ICIs)-treated LUAD patients was analyzed to assess the association of LRP1B mutation with immunotherapy prognosis. Another cohort of LUAD patients with genetic and transcriptomic data was also obtained from The Cancer Genome Atlas (TCGA). By investigating the ICIs and the TCGA-LUAD cohorts, we compared the differences in mutation profiles, immunogenicity, TIME, and DNA damage repair (DDR) mutations between the LRP1B-mutated and LRP1B wild-type groups. Additionally, we performed multiplex immunohistochemistry (mIHC) to validate the differences in the tumor microenvironment. Results: Our results revealed that LRP1B mutation is associated with multiple immune-related pathways. Analysis of TIME indicated that LUAD patients with LRP1B mutation expressed significant levels of genes involved in antigen presentation, cytotoxicity, chemokines, and pro-inflammatory mediators, whereas a few immune checkpoint genes were highly expressed in the LRP1B-mutated group as well. Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) analysis indicated that LRP1B-mutated LUAD patients had higher infiltration of active immune cells. Multiplex IHC analysis showed that LRP1B-mutated LUAD patients had elevated programmed death ligand-1 (PD-L1) expression and immune cell infiltration. Patients with LRP1B mutation had higher tumor mutation burden, neoantigens, as well as more mutated genes in the DDR-related pathways. Finally, LRP1B-mutated LUAD patients showed a significant prolongation of progression-free survival (PFS) in the ICIs cohort and could be effectively predicted by our constructed nomogram. Conclusions: Our study suggests that LRP1B mutation is associated with higher immune cell infiltration and elevated immune gene expression in TIME and potentially serves as a prognostic biomarker for LUAD patients treated with ICIs.

16.
Nat Mater ; 22(5): 583-590, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36894774

RESUMO

Using circularly polarized light to control quantum matter is a highly intriguing topic in physics, chemistry and biology. Previous studies have demonstrated helicity-dependent optical control of chirality and magnetization, with important implications in asymmetric synthesis in chemistry; homochirality in biomolecules; and ferromagnetic spintronics. We report the surprising observation of helicity-dependent optical control of fully compensated antiferromagnetic order in two-dimensional even-layered MnBi2Te4, a topological axion insulator with neither chirality nor magnetization. To understand this control, we study an antiferromagnetic circular dichroism, which appears only in reflection but is absent in transmission. We show that the optical control and circular dichroism both arise from the optical axion electrodynamics. Our axion induction provides the possibility to optically control a family of [Formula: see text]-symmetric antiferromagnets ([Formula: see text], inversion; [Formula: see text], time-reversal) such as Cr2O3, even-layered CrI3 and possibly the pseudo-gap state in cuprates. In MnBi2Te4, this further opens the door for optical writing of a dissipationless circuit formed by topological edge states.

17.
Sci Rep ; 13(1): 4338, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36927890

RESUMO

Mobile pastoralism was a key lifeway in the Late Bronze and Iron Age of Northwest China and played a crucial role in the regional socio-cultural development, as well as the formation of transregional networks. In this paper we analyse the complete faunal assemblage from House F2 in Shirenzigou, on the Eastern Tianshan Mountains, in combination with radiocarbon dating and spatial analysis, to explore local animal resources exploitation strategies and related socio-economic implications. Our results show an intensive multipurpose caprine management, while the exploitation of other domestic taxa, cattle, horses and dogs, was limited. This pastoral economy was supplemented with some hunting. The differentiated use of space in F2 indicates that basic domestic tasks were carried out in the structure, however its position within the landscape and the predominance of bone tools related to warfare and socialization activities, suggests that it was not an ordinary dwelling, it may also have served as a watch post for the summer encampment within the gully. Our findings constitute an important contribution on the discussion on animal resources exploitation strategies and their relationship with evolving socio-economic complexity in the Eastern Tianshan region in the late first millennium BCE.


Assuntos
Arqueologia , Cabras , Animais , Cavalos , Bovinos , Cães , Arqueologia/métodos , China , Osso e Ossos , Datação Radiométrica
18.
Stem Cells Int ; 2023: 5671809, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910334

RESUMO

Periodontal ligament stem cells (PDLSCs) are considered ideal cell sources for the regeneration of periodontal and alveolar bone tissue. Cytoskeleton Regulator RNA (CYTOR), a newly discovered long noncoding RNA, has been reported to function as competing endogenous RNA (ceRNA) and to be involved in many biological processes. However, its roles in PDLSC osteogenic differentiation remain unclear. Here, we firstly found CYTOR was mainly sublocalized in the cytoplasm of PDLSCs and CYTOR expression was increased during osteogenic differentiation of PDLSCs. By employing gain- and loss-of-function approaches, we then identified CYTOR overexpression promoted osteogenic differentiation of PDLSCs while CYTOR knockdown inhibited this process. Furthermore, bioinformatics analysis was utilized to show that both CYTOR and SOX11 mRNA contained the same seed sites for miR-6512-3p, which was further confirmed by dual luciferase reporter assay and RNA-binding protein immunoprecipitation. Notably, CYTOR conferred its functions by directly binding to miR-6512-3p and an inverse correlation between CYTOR and miR-6512-3p on the level on SOX11 and osteogenic differentiation of PDLSCs was obtained. Additionally, miR-6512-3p could bind to SOX11 mRNA 3' UTR and repressed SOX11 expression. Moreover, level of SOX11 was significantly increased during osteogenic differentiation of PDLSCs. Knockdown of SOX11 attenuated the increasing effect of CYTOR overexpression on osteogenic differentiation of PDLSCs. Collectively, these data supported that CYTOR positively modulated the expression of SOX11 through competitively binding to miR-6512-3p, thus promoting osteogenic differentiation of PDLSCs. The CYTOR/miR-6512-3p/SOX11 axis could be a novel therapeutic target for periodontal regeneration medicine.

19.
Microorganisms ; 11(3)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36985120

RESUMO

Lung adenocarcinoma (LADC) is a prevalent type of lung cancer that is associated with lung and gut microbiota. However, the interactions between these microbiota and cancer development remain unclear. In this study, a microbiome study was performed on paired fecal and bronchoalveolar lavage fluid (BALF) samples from 42 patients with LADC and 64 healthy controls using 16S rRNA gene amplicon and shotgun metagenome sequencing, aiming to correlate the lung and gut microbiota with LADC. Patients with LADC had reduced α-diversity in the gut microbiome and altered ß-diversity compared with healthy controls, and the abundances of Flavonifractor, Eggerthella, and Clostridium were higher in the gut microbiome of LADC patients. The increased abundance of microbial species, such as Flavonifractor plautii, was associated with advanced-stage LADC and a higher metastasis rate. Phylogenetically, Haemophilus parainfluenzae was the most frequently shared taxon in the lung and gut microbiota of LADC patients. Gut microbiome functional pathways involving leucine, propanoate, and fatty acids were associated with LADC progression. In conclusion, the low diversity of the gut microbiota and the presence of H. parainfluenzae in gut and lung microbiota were linked to LADC development, while an increased abundance of F. plautii and the enriched metabolic pathways could be associated with the progression of LADC.

20.
Bioorg Chem ; 134: 106447, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36889198

RESUMO

Fifteen new chromones, sadivamones A-E (1-5), cimifugin monoacetate (6), sadivamones F-N (7-15), together with fifteen known chromones (16-30), were isolated from the ethyl acetate portions of 70% ethanol extract of Saposhnikovia divaricata (Turcz.) Schischk roots. The structures of the isolates were determined using 1D/2D NMR data and electron circular dichroism (ECD) calculations. Meanwhile, LPS induced RAW264.7 inflammatory cell model was used to determine the potential anti-inflammatory activity of all the isolated compounds in vitro. The results showed that compounds 2, 8, 12-13, 18, 20-22, 24, and 27 significantly inhibited the production of lipopolysaccharide (LPS)-induced NO in macrophages. To determine the signaling pathways involved in the suppression of NO production by compounds 8, 12 and 13, we investigated ERK and c-Jun N-terminal protein kinase (JNK) expression by western blot analysis. Further mechanistic studies demonstrated that compounds 12 and 13 inhibited the phosphorylation of ERK and the activation of ERK and JNK signaling in RAW264.7 cells via MAPK signaling pathways. Taken together, compounds 12 and 13 may be valuable candidates for the treatment of inflammatory diseases.


Assuntos
Apiaceae , Medicamentos de Ervas Chinesas , Lipopolissacarídeos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Apiaceae/química , Cromonas/farmacologia , Cromonas/química , Anti-Inflamatórios/farmacologia
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