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1.
Nature ; 618(7963): 69-73, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37259001

RESUMO

Since the discovery of X-rays by Roentgen in 1895, its use has been ubiquitous, from medical and environmental applications to materials sciences1-5. X-ray characterization requires a large number of atoms and reducing the material quantity is a long-standing goal. Here we show that X-rays can be used to characterize the elemental and chemical state of just one atom. Using a specialized tip as a detector, X-ray-excited currents generated from an iron and a terbium atom coordinated to organic ligands are detected. The fingerprints of a single atom, the L2,3 and M4,5 absorption edge signals for iron and terbium, respectively, are clearly observed in the X-ray absorption spectra. The chemical states of these atoms are characterized by means of near-edge X-ray absorption signals, in which X-ray-excited resonance tunnelling (X-ERT) is dominant for the iron atom. The X-ray signal can be sensed only when the tip is located directly above the atom in extreme proximity, which confirms atomically localized detection in the tunnelling regime. Our work connects synchrotron X-rays with a quantum tunnelling process and opens future X-rays experiments for simultaneous characterizations of elemental and chemical properties of materials at the ultimate single-atom limit.

2.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38673861

RESUMO

Plant-parasitic nematodes (PPNs) are among the most serious phytopathogens and cause widespread and serious damage in major crops. In this study, using a genome mining method, we identified nonribosomal peptide synthetase (NRPS)-like enzymes in genomes of plant-parasitic nematodes, which are conserved with two consecutive reducing domains at the N-terminus (A-T-R1-R2) and homologous to fungal NRPS-like ATRR. We experimentally investigated the roles of the NRPS-like enzyme (MiATRR) in nematode (Meloidogyne incognita) parasitism. Heterologous expression of Miatrr in Saccharomyces cerevisiae can overcome the growth inhibition caused by high concentrations of glycine betaine. RT-qPCR detection shows that Miatrr is significantly upregulated at the early parasitic life stage (J2s in plants) of M. incognita. Host-derived Miatrr RNA interference (RNAi) in Arabidopsis thaliana can significantly decrease the number of galls and egg masses of M. incognita, as well as retard development and reduce the body size of the nematode. Although exogenous glycine betaine and choline have no obvious impact on the survival of free-living M. incognita J2s (pre-parasitic J2s), they impact the performance of the nematode in planta, especially in Miatrr-RNAi plants. Following application of exogenous glycine betaine and choline in the rhizosphere soil of A. thaliana, the numbers of galls and egg masses were obviously reduced by glycine betaine but increased by choline. Based on the knowledge about the function of fungal NRPS-like ATRR and the roles of glycine betaine in host plants and nematodes, we suggest that MiATRR is involved in nematode-plant interaction by acting as a glycine betaine reductase, converting glycine betaine to choline. This may be a universal strategy in plant-parasitic nematodes utilizing NRPS-like ATRR to promote their parasitism on host plants.


Assuntos
Arabidopsis , Betaína , Peptídeo Sintases , Tylenchoidea , Betaína/metabolismo , Animais , Tylenchoidea/metabolismo , Tylenchoidea/genética , Arabidopsis/parasitologia , Arabidopsis/metabolismo , Arabidopsis/genética , Peptídeo Sintases/metabolismo , Peptídeo Sintases/genética , Interações Hospedeiro-Parasita , Doenças das Plantas/parasitologia , Proteínas de Helminto/metabolismo , Proteínas de Helminto/genética , Nematoides/metabolismo , Nematoides/genética
3.
Int J Mol Sci ; 23(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36142347

RESUMO

Peptidases are very important to parasites, which have central roles in parasite biology and pathogenesis. In this study, by comparative genome analysis, genome-wide peptidase diversities among plant-parasitic nematodes are estimated. We find that genes encoding cysteine peptidases in family C13 (legumain) are significantly abundant in pine wood nematodes Bursaphelenchus genomes, compared to those in other plant-parasitic nematodes. By phylogenetic analysis, a clade of B. xylophilus-specific legumain is identified. RT-qPCR detection shows that these genes are highly expressed at early stage during the nematode infection process. Utilizing transgene technology, cDNAs of three species-specific legumain were introduced into the Arabidopsis γvpe mutant. Functional complementation assay shows that these B. xylophilus legumains can fully complement the activity of Arabidopsis γVPE to mediate plant cell death triggered by the fungal toxin FB1. Secretory activities of these legumains are experimentally validated. By comparative transcriptome analysis, genes involved in plant cell death mediated by legumains are identified, which enrich in GO terms related to ubiquitin protein transferase activity in category molecular function, and response to stimuli in category biological process. Our results suggest that B. xylophilu-specific legumains have potential as effectors to be involved in nematode-plant interaction and can be related to host cell death.


Assuntos
Arabidopsis , Micotoxinas , Parasitos , Pinus , Rabditídios , Tylenchida , Animais , Arabidopsis/genética , Cisteína/genética , Cisteína Endopeptidases , Peptídeo Hidrolases/genética , Filogenia , Pinus/parasitologia , Doenças das Plantas/parasitologia , Plantas/parasitologia , Transferases/genética , Tylenchida/genética , Ubiquitinas/genética , Virulência , Xylophilus
4.
J Environ Manage ; 323: 116256, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36126592

RESUMO

Defects and vacancies are the essential reasons for the removal of heavy metal ions from wastewater by low-cost biochar materials. This study aimed to use chemically activated hemp stem core alkali extraction residue biochar as an adsorbent to remove nickel (Ni) and copper (Cu) ions from the simulated waste liquid. A large number of defects and vacancies were introduced into the pyrolysis process to study the efficient removal of heavy metal ions Cu and Ni by hemp rod biomass carbon material (HSR-BC) with different carbon base mass ratios and temperatures. The specific surface area of the prepared hemp rod active biochar was highly correlated with the aperture and carbon base ratio and temperature, and reached the maximum value (1429 m2/g) at 600 °C with the ratio of carbon to base (1:3.5). The removal rates of heavy metals Ni(II) and Cu(II) were as high as 94.25% and 99.54%, respectively, and the adsorption capacities were up to 7.85 mg/g and 24.88 mg/g. The adsorption isotherm follows the Langmuir equation and chemo-adsorption was the main adsorption process. Comparing the surface defects and vacancies of biochar materials before and after adsorption showed that the defects of sp-C and oxygen vacancies produced on the edge of the carbon were the main active sites of the biochar material, an amount of carbon defects would become an anchor site for the Lewis acidic groups, the defective acid site strengthened the electron transfer between the functional group and the Ni(II)/Cu(II), promoted the strong cooperation of Ni(II)/Cu(II) ions with -COOH group to enable efficient and rapid adsorption removal. In addition, a large number of carbon-deficient structures could quickly anchor the Ni(II)/Cu(II) due to their local electron deficiency state, which was difficult to desorb. This study provided an in-depth understanding and guidance for the development of low-cost biochar materials with excellent removal performance of heavy metal ions.


Assuntos
Cannabis , Metais Pesados , Poluentes Químicos da Água , Adsorção , Álcalis , Carbono , Carvão Vegetal , Cobre , Íons , Cinética , Metais Pesados/química , Níquel , Oxigênio , Águas Residuárias , Poluentes Químicos da Água/química
5.
Appl Microbiol Biotechnol ; 103(17): 7111-7128, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31273397

RESUMO

The fungus Isaria javanica is an important entomopathogen that parasitizes various insects and is effective for pest control. In this study, we sequenced and assembled the genomes (IJ1G and IJ2G) of two I. javanica strains isolated from different insects. The genomes were approximately 35 Mb in size with 11,441 and 11,143 protein-coding genes, respectively. Using a phylogenomic approach, we evaluated genome evolution across five entomopathogenic fungi in Cordycipitaceae. By comparative genome analysis, it was found that family S53 serine peptidases were expanded in Cordycipitaceae entomopathogens, particularly in I. javanica. Gene duplication events were identified based on phylogenetic relationships inferred from 82 S53 peptidases within six entomopathogenic fungal genomes. Moreover, we found that carbohydrate-active enzymes and proteinases were the largest secretory protein groups encoded in the I. javanica genome, especially chitinases (GH18), serine and aspartic peptidases (S53, S08, S10, A01). Pathogenesis-related genes and genes for bacterial-like toxins and secondary metabolites were also identified. By comparative transcriptome analysis, differentially expressed genes in response to insect nutrients (in vitro) were identified. Moreover, most S53 peptidases were detected to be significantly upregulated during the initial fungal infection process in insects (in vivo) by RT-qPCR. Our results provide new clues about understanding evolution of pathogenic proteases and may suggest that abundant S53 peptidases in the I. javanica genome may contribute to its effective parasitism on various insects.


Assuntos
Cordyceps/genética , Proteínas Fúngicas/genética , Genoma Fúngico/genética , Insetos/microbiologia , Peptídeo Hidrolases/genética , Animais , Cordyceps/classificação , Proteínas Fúngicas/metabolismo , Duplicação Gênica , Regulação Fúngica da Expressão Gênica , Hypocreales/classificação , Hypocreales/genética , Peptídeo Hidrolases/metabolismo , Filogenia , Transcriptoma
6.
Bioorg Med Chem Lett ; 27(4): 829-833, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28109785

RESUMO

A series of novel 12N-substituted matrinane derivatives were synthesized and evaluated for their activities against coxsackievirus type B3 (CVB3) taking compound 1 as the lead. SAR analysis indicated that the introduction of a suitable heteroaromatic ring on the 12N-atom might be beneficial for the activity. Among them, compound 8a exhibited the highest potency against all CVB serotypes as well as CVA16 with IC50 values ranging from 2.02µM to 7.41µM, indicating a broad-spectrum anti-coxsackieviruse effect. Furthermore, compound 8a demonstrated a good safety profile in vivo. Thus, we consider 12N-substituted matrinanes to be a promising family of anti-coxsackievirus agents, and compound 8a to be a promising drug candidate in the treatment of various diseases related to coxsackievirus infection.


Assuntos
Alcaloides/química , Antivirais/química , Alcaloides/síntese química , Alcaloides/farmacologia , Animais , Antivirais/síntese química , Antivirais/farmacologia , Enterovirus/efeitos dos fármacos , Enterovirus Humano B/efeitos dos fármacos , Dose Letal Mediana , Camundongos , Relação Estrutura-Atividade
7.
Yao Xue Xue Bao ; 51(5): 756-61, 2016 05.
Artigo em Zh | MEDLINE | ID: mdl-29874022

RESUMO

12-N-Benzenesulfonyl-11-matrinic acid derivatives are a new class of anti-CVB3 compounds, but the mechanism of action is still unknown. Therein, two kinds of molecule probes were designed and constructed in this study, including matrinic amines that might be applied to the BIAcore fishing technique and biotin-tagged matrinic derivatives, which could be applied in the biotin affinity chromatography. Moreover, their anti-CVB3 activities were evaluated. Among them,10a displayed a good activity with an IC(50) value of 0.8 µmol·L(-1).This active molecule probe provides a key chemical tool for exploration of the anti-CVB3 mechanism of this type of compounds.


Assuntos
Ácidos Carbocíclicos/química , Sondas Moleculares/química , Cromatografia de Afinidade
8.
Yao Xue Xue Bao ; 51(4): 606-12, 2016 04.
Artigo em Zh | MEDLINE | ID: mdl-29859656

RESUMO

12-N-m-Cyanobenzenesulfonyl matrinic butyl methyl ether is a potent anti-coxsackievirus B3(CVB3) agent bearing a novel structure skeleton. Taking this compound as a lead, totally 15 novel target compounds have been synthesized and evaluated for the anti-CVB3 activities using CPE method. Structure- activity relationship(SAR)demonstrated that the shorten-length of 11-side chain was not helpful for keeping the good anti-virus activity. Among the newly synthesized compounds, compound c1 displayed a good anti-CVB3 activity with the IC(50) of 7.1 µmol·L(-1) and SI of 35.5, similar to that of the lead. The SAR results provided useful information for further optimization of these compounds in the molecular structure.


Assuntos
Antivirais/farmacologia , Enterovirus Humano B/efeitos dos fármacos , Éteres/farmacologia , Antivirais/síntese química , Éteres/síntese química , Estrutura Molecular , Relação Estrutura-Atividade
9.
BMC Microbiol ; 15: 5, 2015 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-25636983

RESUMO

BACKGROUND: The fungus Pochonia chlamydosporia parasitizes nematode eggs and has become one of the most promising biological control agents (BCAs) for plant-parasitic nematodes, which are major agricultural pests that cause tremendous economic losses worldwide. The complete mitochondrial (mt) genome is expected to open new avenues for understanding the phylogenetic relationships and evolution of the invertebrate-pathogenic fungi in Hypocreales. RESULTS: The complete mitogenome sequence of P. chlamydosporia is 25,615 bp in size, containing the 14 typical protein-coding genes, two ribosomal RNA genes, an intronic ORF coding for a putative ribosomal protein (rps3) and a set of 23 transfer RNA genes (trn) which recognize codons for all amino acids. Sequence similarity studies and syntenic gene analyses show that 87.02% and 58.72% of P. chlamydosporia mitogenome sequences match 90.50% of Metarhizium anisopliae sequences and 61.33% of Lecanicillium muscarium sequences with 92.38% and 86.04% identities, respectively. A phylogenetic tree inferred from 14 mt proteins in Pezizomycotina fungi supports that P. chlamydosporia is most closely related to the entomopathogenic fungus M. anisopliae. The invertebrate-pathogenic fungi in Hypocreales cluster together and clearly separate from a cluster comprising plant-pathogenic fungi (Fusarium spp.) and Hypocrea jecorina. A comparison of mitogenome sizes shows that the length of the intergenic regions or the intronic regions is the major size contributor in most of mitogenomes in Sordariomycetes. Evolutionary analysis shows that rps3 is under positive selection, leading to the display of unique evolutionary characteristics in Hypocreales. Moreover, the variability of trn distribution has a clear impact on gene order in mitogenomes. Gene rearrangement analysis shows that operation of transposition drives the rearrangement events in Pezizomycotina, and most events involve in trn position changes, but no rearrangement was found in Clavicipitaceae. CONCLUSIONS: We present the complete annotated mitogenome sequence of P. chlamydosporia. Based on evolutionary and phylogenetic analyses, we have determined the relationships between the invertebrate-pathogenic fungi in Hypocreales. The invertebrate-pathogenic fungi in Hypocreales referred to in this paper form a monophyletic group sharing a most recent common ancestor. Our rps3 and trn gene order results also establish a foundation for further exploration of the evolutionary trajectory of the fungi in Hypocreales.


Assuntos
DNA Fúngico/genética , DNA Mitocondrial/genética , Genoma Mitocondrial , Hypocreales/classificação , Hypocreales/genética , Análise por Conglomerados , DNA Fúngico/química , DNA Mitocondrial/química , Ordem dos Genes , Genes Fúngicos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Homologia de Sequência , Sintenia
10.
Bioorg Med Chem Lett ; 25(17): 3690-3, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26112440

RESUMO

A novel series of N-benzenesulfonyl matrinic amine/amide and matrinic methyl ether analogues were designed, synthesized and evaluated for their in vitro anti-coxsackievirus B3 (CVB3) activities. The structure-activity relationship (SAR) studies revealed that introduction of a suitable amide substituent on position 4' could greatly enhance the antivirus potency. Compared to the lead compounds, the newly synthesized matrinic amide derivatives 21c-d and 21j exhibited stronger anti-CVB3 activities with lower micromolar IC50 from 2.5 µM to 2.7 µM, and better therapeutic properties with improved selectivity index (SI) from 63 to 67. The SAR results provided powerful information for further strategic optimization, and these top compounds were selected for the next evaluation as novel enterovirus inhibitors.


Assuntos
Antivirais/química , Antivirais/farmacologia , Enterovirus Humano B/efeitos dos fármacos , Relação Estrutura-Atividade , Animais , Técnicas de Química Sintética , Chlorocebus aethiops , Avaliação Pré-Clínica de Medicamentos/métodos , Enterovirus Humano B/patogenicidade , Células Vero/efeitos dos fármacos , Células Vero/virologia
11.
Clin Respir J ; 18(8): e13801, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39135128

RESUMO

BACKGROUND: circRNA NFIX has been shown to exist as an oncogene in glioma. But its expression and role in NSCLC (non-small cell lung cancer) are still unclear. This research aimed to discover the expression and function of circRNA NFIX in NSCLC. METHODS: In this research, qRT-PCR was utilized to investigate the expression levels of circRNA NFIX, miRNA-214-3p, and TRIAP1 in NSCLC tissues and cell lines. The binding sites between circRNA NFIX/TRIAP1 and miRNA-214-3p were predicted using the Starbase. These interactions were further validated using a double luciferase reporter assay. Cell proliferation and apoptosis were assessed through MTT and flow cytometry, respectively. The expression of apoptosis-related proteins was measured by western blot assay. RESULTS: miRNA-214-3p could link with circRNA NFIX. circRNA NFIX was upregulated, while miRNA-214-3p was downregulated in NSCLC cell lines and clinical samples. Besides, suppression of circRNA NFIX repressed cell proliferation and induced apoptosis in NSCLC cells by upregulating miRNA-214-3p expression. Besides, the data indicated that TRIAP1 was a target of miRNA-214-3p, and it was negatively regulated by miRNA-214-3p in NSCLC cells. The excessive expression of miRNA-214-3p suppressed NSCLC cell proliferation and increased apoptosis. In addition, overexpression of TRIAP1 significantly reversed the effects on NSCLC cells caused by miRNA-214-3p mimic. CONCLUSION: circRNA NFIX silencing repressed the proliferation of NSCLC cells and induced cell apoptosis by regulating the miR-214-3p/TRIAP1 axis, which was a potential diagnostic and therapeutic target for NSCLC.


Assuntos
Apoptose , Carcinoma Pulmonar de Células não Pequenas , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares , MicroRNAs , Fatores de Transcrição NFI , RNA Circular , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Proliferação de Células/genética , Fatores de Transcrição NFI/genética , Fatores de Transcrição NFI/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Oncogenes/genética , Regulação para Cima , Peptídeos e Proteínas de Sinalização Intracelular
12.
ACS Appl Mater Interfaces ; 16(37): 49337-49348, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39251359

RESUMO

Flexible solid-state supercapacitors (SCs) with hydrogel as an electrolyte and separator combine the advantages of wearability and energy storage and exhibit a broad application prospect in wearable energy textiles. However, irreversible electrolyte damage and unstable electrode-electrolyte interfaces during mechanical deformations remain bottlenecks in realizing truly wearable applications. Herein, poly(acrylic acid) (PAA)-Fe hydrogels were prepared through a simple thermal polymerization strategy. The dynamic reversible metal coordination bonds between Fe3+ and carboxylic acids confers the hydrogels with excellent self-healing properties. As expected, the prepared hydrogels exhibited superior mechanical strength (tensile stress of 45.80 kPa), ionic conductivity (0.076 S cm-1), and self-healing properties. Subsequently, the SCs were constructed using composite hydrogel electrodes (MnO2@CC embedded in the PAA-Fe hydrogels) as symmetrical electrodes (marked as MSCs). The reversible metal coordination bonds between composite hydrogel electrodes formed an ultrastable electrode/electrolyte interface in the all-in-one MSCs, thus revealing excellent mechanical durability. The all-in-one MSCs delivered a remarkable specific capacitance (30.98 F g-1 at 0.2 A g-1), excellent cyclic stability (87.24% after 5000 cycles), outstanding mechanical deformation stability, and impressive electrochemical output stability after self-healing (capacitance retention of 85.34% after five cycles of cutting/self-healing). It is noteworthy that the all-in-one MSCs employed NaCl as an electrolyte, which can be obtained from human sweat. As a proof of the self-charged concept, the all-in-one MSCs can be reused in sweat, whose capacitance was maintained at 90.05% of the initial state after three repetitions. This work is expected to shine light into the design of all-in-one and fabric-based SCs and the development of wearable energy textiles.

13.
Acta Psychol (Amst) ; 243: 104149, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38245937

RESUMO

Insomnia, which is highly prevalent among college students, has been identified as one of the negative consequences of childhood maltreatment. While prior studies have uncovered distinct correlations between childhood maltreatment, insomnia, and other variables, the potential underlying mechanisms need to be further explored. This study focused on the chain-mediating role of alexithymia and psychological distress in the relationship between childhood maltreatment and insomnia. An online cross-sectional survey was conducted among Chinese college students, yielding 999 valid questionnaires that included demographic information, the Childhood Trauma Questionnaire-Short Form (CTQ-SF), the Toronto Alexithymia Scale (TAS), the 21-item Depression Anxiety Stress Scales (DASS-21), and the Insomnia Severity Index (ISI). A chain-mediating model was then tested. The results revealed significant positive correlations between each pair of the four variables. Alexithymia and psychological distress separately mediated the link between childhood maltreatment and insomnia (effect of alexithymia was 0.06 with 95 % CI [0.03, 0.09]; effect of psychological distress was 0.24 with 95 % CI [0.19, 0.29]). Additionally, a chain-mediating effect of alexithymia and psychological distress was observed (chain-mediating effect was 0.12 with 95 % CI [0.09, 0.15]). The findings suggest that emotional interventions may mitigate the long-term effect of childhood maltreatment on sleep problems among college students, by improving the ability to recognize emotions and decreasing emotional problems.


Assuntos
Maus-Tratos Infantis , Angústia Psicológica , Testes Psicológicos , Autorrelato , Distúrbios do Início e da Manutenção do Sono , Criança , Humanos , Sintomas Afetivos/epidemiologia , Sintomas Afetivos/psicologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Estudos Transversais , Maus-Tratos Infantis/psicologia , Estudantes/psicologia
14.
Ultrason Sonochem ; 108: 106958, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38889569

RESUMO

Fermented skim milk is an ideal food for consumers such as diabetic and obese patients, but its low-fat content affects its texture and viscosity. In this study, we developed an effective pretreatment method for fermented skim milk using low-frequency ultrasound (US), and investigated the molecular mechanism of the corresponding quality improvement. The skim milk samples were treated by optimal ultrasonication conditions (336 W power for 7 min at 3 °C), which improved the viscosity, water-holding capacity, sensory attributes, texture, and microstructure of fermented skim milk (P < 0.05). Further mechanistic analyses revealed that the US treatment enhanced the exposure of fluorescent amino acids within proteins, facilitating the cross-linking between casein and whey. The increased surface hydrophobicity of fermented milk indicates that the US treatment led to the exposure of hydrophobic amino acid residues inside proteins, contributing to the formation of a denser gel network; the average particle size of milk protein was reduced from 24.85 to 18.06 µm, which also contributed to the development of a softer curd texture. This work is the first attempt to explain the effect of a low-frequency ultrasound treatment on the quality of fermented skim milk and discuss the molecular mechanism of its improvement.


Assuntos
Fermentação , Leite , Leite/química , Animais , Manipulação de Alimentos/métodos , Ondas Ultrassônicas , Sonicação , Interações Hidrofóbicas e Hidrofílicas , Qualidade dos Alimentos , Viscosidade
15.
Transl Stroke Res ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39322815

RESUMO

Disruption of the blood-brain barrier (BBB) is an important pathological hallmark of ischemic stroke. Blood-brain barrier disruption (BBBD) is a consequence of ischemia and may also exacerbate damage to brain parenchyma. Therefore, maintaining BBB integrity is critical for the central nervous system (CNS) homeostasis. This review offers a concise overview of BBB structure and function, along with the mechanisms underlying its impairment following a stroke. In addition, we review the recent imaging techniques employed to study blood-brain barrier permeability (BBBP) in the context of ischemic brain injury with the goal of providing imaging guidance for stroke diagnosis and treatment from the perspective of the BBBD. This knowledge is vital for developing strategies to safeguard the BBB during cerebral ischemia.

16.
J Fungi (Basel) ; 10(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38248977

RESUMO

The endoparasitic fungus Hirsutella rhossiliensis is an important biocontrol agent of cyst nematodes in nature. To determine the potential parasitism of the fungus on a non-natural host, the pinewood nematode (Bursaphelenchus xylophilus) living in pine trees and the endophytic ability of the fungus on plants, in this paper, we first constructed and utilized a green fluorescent protein (GFP)-tagged H. rhossiliensis HR02 transformant to observe the fungal infection process on B. xylophilus and its colonization on Arabidopsis roots. Then, we compared the fungal parasitism on three species of nematodes with different lifestyles, and we found that the fungal parasitism is correlated with nematode species and stages. The parasitic effect of H. rhossiliensis on adults of B. xylophilus is similar to that on second-stage juveniles (J2) of the root-knot nematode Meloidogyne incognita after 24 h of inoculation, although the virulence of the fungus to second-stage juveniles of M. incognita is stronger than that to those of B. xylophilus and Caenorhabditis elegans. Moreover, the endophytism of H. rhossiliensis was confirmed. By applying an appropriate concentration of H. rhossiliensis conidial suspension (5 × 106 spores/mL) in rhizosphere soil, it was found that the endophytic fungus can promote A. thaliana growth and reproduction, as well as improve host resistance against M. incognita. Our results provide a deeper understanding of the fungus H. rhossiliensis as a promising biocontrol agent against plant-parasitic nematodes.

17.
Adv Sci (Weinh) ; 11(17): e2400557, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38419378

RESUMO

In nature, spider web is an interwoven network with high stability and elasticity from silk threads secreted by spider. Inspired by the structure of spider webs, light-driven liquid crystal elastomer (LCE) active yarn is designed with super-contractile and robust weavability. Herein, a novel biomimetic gold nanorods (AuNRs) @LCE yarn soft actuator with hierarchical structure is fabricated by a facile electrospinning and subsequent photocrosslinking strategies. Meanwhile, the inherent mechanism and actuation performances of the as-prepared yarn actuator with interleaving network are systematically analyzed. Results demonstrate that thanks to the unique "like-spider webs" structure between fibers, high molecular orientation within the LCE microfibers and good flexibility, they can generate super actuation strain (≈81%) and stable actuation performances. Importantly, benefit from the robust covalent bonding at the organic-inorganic interface, photopolymerizable AuNRs molecules are uniformly introduced into the polymer backbone of electrospun LCE yarn to achieve tailorable shape-morphing under different light intensity stimulation. As a proof-of-concept illustration, light-driven artificial muscles, micro swimmers, and hemostatic bandages are successfully constructed. The research disclosed herein can offer new insights into continuous production and development of LCE-derived yarn actuator that are of paramount significance for many applications from smart fabrics to flexible wearable devices.

18.
Adv Sci (Weinh) ; 11(13): e2308813, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38268161

RESUMO

Rare-earth complexes are vital for separation chemistry and useful in many advanced applications including emission and energy upconversion. Here, 2D rare-earth clusters having net charges are formed on a metal surface, enabling investigations of their structural and electronic properties on a one-cluster-at-a-time basis using scanning tunneling microscopy. While these ionic complexes are highly mobile on the surface at ≈100 K, their mobility is greatly reduced at 5 K and reveals stable and self-limiting clusters. In each cluster, a pair of charged rare-earth complexes formed by electrostatic and dispersive interactions act as a basic unit, and the clusters are chiral. Unlike other non-ionic molecular clusters formed on the surfaces, these rare-earth clusters show mechanical stability. Moreover, their high mobility on the surface suggests that they are in a 2D liquid-like state.

19.
Medicine (Baltimore) ; 102(36): e35023, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37682183

RESUMO

Stroke patients may have dysphagia and frequent aspiration increasing exposure to antibiotics and the chance of multidrug-resistant (MDR) bacteria infection. This study investigated clinical risk factors and related antibiotic use of MDR bacteria infection in stroke patients in the rehabilitation ward, hoping that it can help prevent and reduce the condition of MDR bacteria. A retrospective cohort study was conducted using the database of stroke patients with pneumonia admitted to the rehabilitation ward from January 1, 2020, to June 30, 2022. The selected stroke patients were divided into the MDR and non-MDR groups. Analyze the infection bacteria of the 2 groups. Forward logistic regression was applied to identify possible independent MDR bacteria infection risk factors. A total of 323 patients were included. The top 3 common MDR pathogens were Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii. Almost all Pseudomonas aeruginosa and Acinetobacter baumannii are resistant to ertapenem. National Institute of Health stroke scale at admission was associated with MDR bacteria infection pneumonia (OR [odds ratio] = 1.078, 95%CI [1.017, 1.142]). Long-term tracheotomy (OR = 2.695, 95%CI [1.232, 5.897]), hypoalbuminemia (OR = 473, 95%CI [1.318, 4.642]), and bilateral cerebral hemisphere stroke (OR = 4.021, 95%CI [2.009, 8.048]) were significant clinical risk factors of MDR pneumonia after stroke. The detection rate of MDR bacteria has increased. Understanding the distribution and drug resistance of MDR bacteria in stroke patients with pneumonia in the neurological rehabilitation ward and the related susceptibility of MDR bacteria infection is necessary. This way, the treatment plan can be adjusted more timely, avoiding the abuse of antibiotics.


Assuntos
Acinetobacter baumannii , Pneumonia , Humanos , Estudos Retrospectivos , Centros de Reabilitação , Pneumonia/tratamento farmacológico , Pneumonia/epidemiologia , Antibacterianos/uso terapêutico , Bactérias
20.
Artigo em Inglês | MEDLINE | ID: mdl-37908058

RESUMO

Fiber-based supercapacitors (FSCs) exhibit desirable application potential and development prospects in wearable energy storage devices because of their flexibility and wearability. However, the low capacity in the unit volume and insufficient fiber strength hinder their further development in practical application. Herein, the MnO2 nanomaterials with regulatable crystalline structure were synthesized by one-step hydrothermal strategy. The formation of the MnO2 crystalline structure involved the "crimp-phase transition" process. Among them, the 2 × 2 tunnel type α-MnO2 nanowires exhibited excellent electrochemical capacitance (43.8 F g-1), high rate performance (61%, 0.25 to 6 A g-1), and remarkable cyclic stability (99%), which can be attributed to their good symmetry in space and high shared vertices proportion. On this basis, the α-MnO2 nanowires were coblended with GO to construct MnO2/rGO hybrid fibers by scalable continuous wet spinning and in situ acid reduction. Noteworthily, in MnO2/rGO hybrid fibers, the doping amount of MnO2 nanowires as high as 50 wt % could be achieved, while the strength reached 11.73 MPa, which can be ascribed to the superior surface morphology of MnO2 nanowires and the unique cement wall structure of hybrid fibers. Finally, the obtained hybrid fiber electrodes were assembled into symmetrical FSCs. Notably, the FSCs delivered remarkable volume specific capacitance (129.5 F cm-3) and impressive energy density (18 mWh cm-3) at 1.75 A cm-3. In addition, the assembled all-solid-state FSCs indicated excellent deformability and application potential. This work offers some insight for promoting the continuous preparation of fiber electrodes, the development of FSCs, and practical application in wearable energy textile.

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