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1.
Hepatology ; 77(6): 1983-1997, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36645226

RESUMO

BACKGROUND AND AIMS: Interferon (IFN) signaling is critical to the pathogenesis of alcohol-associated hepatitis (AH), yet the mechanisms for activation of this system are elusive. We hypothesize that host-derived 5S rRNA pseudogene (RNA5SP) transcripts regulate IFN production and modify immunity in AH. APPROACH AND RESULTS: Mining of transcriptomic datasets revealed that in patients with severe alcohol-associated hepatitis (sAH), hepatic expression of genes regulated by IFNs was perturbed and gene sets involved in IFN production were enriched. RNA5SP transcripts were also increased and correlated with expression of type I IFNs. Interestingly, inflammatory mediators upregulated in sAH, but not in other liver diseases, were positively correlated with certain RNA5SP transcripts. Real-time quantitative PCR demonstrated that RNA5SP transcripts were upregulated in peripheral blood mononuclear cells (PBMCs) from patients with sAH. In sAH livers, increased 5S rRNA and reduced nuclear MAF1 (MAF1 homolog, negative regulator of RNA polymerase III) protein suggested a higher activity of RNA polymerase III (Pol III); inhibition of Pol III reduced RNA5SP expression in monocytic THP-1 cells. Expression of several RNA5SP transcript-interacting proteins was downregulated in sAH, potentially unmasking transcripts to immunosensors. Indeed, siRNA knockdown of interacting proteins potentiated the immunostimulatory activity of RNA5SP transcripts. Molecular interaction and cell viability assays demonstrated that RNA5SP transcripts adopted Z-conformation and contributed to ZBP1-mediated caspase-independent cell death. CONCLUSIONS: Increased expression and binding availability of RNA5SP transcripts was associated with hepatic IFN production and inflammation in sAH. These data identify RNA5SP transcripts as a potential target to mitigate inflammation and hepatocellular injury in AH.


Assuntos
Técnicas Biossensoriais , Hepatite Alcoólica , Interferon Tipo I , Humanos , RNA Ribossômico 5S/genética , RNA Ribossômico 5S/metabolismo , Pseudogenes , RNA Polimerase III/genética , RNA Polimerase III/metabolismo , Leucócitos Mononucleares , Imunoensaio , Inflamação/genética , Hepatite Alcoólica/genética , Interferon Tipo I/genética
2.
Hepatology ; 77(3): 902-919, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35689613

RESUMO

BACKGROUND AND AIMS: Mixed lineage kinase domain-like pseudokinase (MLKL), a key terminal effector of necroptosis, also plays a role in intracellular vesicle trafficking that is critical for regulating liver inflammation and injury in alcohol-associated liver disease (ALD). Although receptor interacting protein kinase 3 (Rip3)-/- mice are completely protected from ethanol-induced liver injury, Mlkl-/- mice are only partially protected. Therefore, we hypothesized that cell-specific functions of MLKL may contribute to ethanol-induced injury. APPROACH AND RESULTS: Bone marrow transplants between Mlkl-/- mice and littermates were conducted to distinguish the role of myeloid versus nonmyeloid Mlkl in the Gao-binge model of ALD. Ethanol-induced hepatic injury, steatosis, and inflammation were exacerbated in Mlkl-/- →wild-type (WT) mice, whereas Mlkl deficiency in nonmyeloid cells (WT→ Mlkl-/- ) had no effect on Gao-binge ethanol-induced injury. Importantly, Mlkl deficiency in myeloid cells exacerbated ethanol-mediated bacterial burden and accumulation of immune cells in livers. Mechanistically, challenging macrophages with lipopolysaccharide (LPS) induced signal transducer and activator of transcription 1-mediated expression and phosphorylation of MLKL, as well as translocation and oligomerization of MLKL to intracellular compartments, including phagosomes and lysosomes but not plasma membrane. Importantly, pharmacological or genetic inhibition of MLKL suppressed the phagocytic capability of primary mouse Kupffer cells (KCs) at baseline and in response to LPS with/without ethanol as well as peripheral monocytes isolated from both healthy controls and patients with alcohol-associated hepatitis. Further, in vivo studies revealed that KCs of Mlkl-/- mice phagocytosed fewer bioparticles than KCs of WT mice. CONCLUSION: Together, these data indicate that myeloid MLKL restricts ethanol-induced liver inflammation and injury by regulating hepatic immune cell homeostasis and macrophage phagocytosis.


Assuntos
Hepatite Alcoólica , Hepatopatias Alcoólicas , Camundongos , Animais , Lipopolissacarídeos/metabolismo , Hepatopatias Alcoólicas/metabolismo , Fígado/metabolismo , Etanol/toxicidade , Hepatite Alcoólica/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Fagocitose , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Camundongos Endogâmicos C57BL , Proteínas Quinases/genética , Proteínas Quinases/metabolismo
3.
Plant Cell Environ ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808618

RESUMO

Bursaphelenchus xylophilus is the pathogen of pine wilt disease, which can devastate the pine forest ecosystem. Usually, plant cells generate reactive oxygen species (ROS) as a defensive substance or signalling molecules to resist the infection of nematodes. However, little is known about how B. xylophilus effectors mediate the plant ROS metabolism. Here, we identified a pioneer B. xylophilus Prx3-interacting effector 1 (BxPIE1) expressed in the dorsal gland cells and the intestine. Silencing of the BxPIE1 gene resulted in reduced nematode reproduction and a delay in disease progression during parasitic stages, with the upregulation of pathogenesis-related (PR) genes PtPR-3 (class Ⅳ chitinase) and PtPR-9 (peroxidase). The protein-protein interaction assays further demonstrated that BxPIE1 interacts with a Pinus thunbergii class III peroxidase (PtPrx3), which produces H2O2 under biotic stress. The expression of BxPIE1 and PtPrx3 was upregulated during the infection stage. Furthermore, BxPIE1 effectively inhibited H2O2 generating from class III peroxidase and ascorbate can recover the virulence of siBxPIE1-treated B. xylophilus by scavenging H2O2. Taken together, BxPIE1 is an important virulence factor, revealing a novel mechanism utilized by nematodes to suppress plant immunity.

4.
Environ Sci Technol ; 58(16): 7056-7065, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38608141

RESUMO

The sources and sinks of nitrous oxide, as control emissions to the atmosphere, are generally poorly constrained for most environmental systems. Initial depth-resolved analysis of nitrous oxide flux from observation wells and the proximal surface within a nitrate contaminated aquifer system revealed high subsurface production but little escape from the surface. To better understand the environmental controls of production and emission at this site, we used a combination of isotopic, geochemical, and molecular analyses to show that chemodenitrification and bacterial denitrification are major sources of nitrous oxide in this subsurface, where low DO, low pH, and high nitrate are correlated with significant nitrous oxide production. Depth-resolved metagenomes showed that consumption of nitrous oxide near the surface was correlated with an enrichment of Clade II nitrous oxide reducers, consistent with a growing appreciation of their importance in controlling release of nitrous oxide to the atmosphere. Our work also provides evidence for the reduction of nitrous oxide at a pH of 4, well below the generally accepted limit of pH 5.


Assuntos
Óxido Nitroso , Óxido Nitroso/metabolismo , Bactérias/metabolismo , Oxirredutases/metabolismo , Desnitrificação
5.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791195

RESUMO

Pinus thunbergii Parl. is an economically and medicinally important plant, as well as a world-renowned horticultural species of the Pinus genus. Pine wilt disease is a dangerous condition that affects P. thunbergii. However, understanding of the genetics underlying resistance to this disease is poor. Our findings reveal that P. thunbergii's resistance mechanism is based on differential transcriptome responses generated by the early presence of the pathogen Bursaphelenchus xylophilus, also known as the pine wood nematode. A transcriptome analysis (RNA-seq) was performed to examine gene expression in shoot tissues from resistant and susceptible P. thunbergii trees. RNA samples were collected from the shoots of inoculated pines throughout the infection phases by the virulent Bursaphelenchus xylophilus AMA3 strain. The photosynthesis and plant-pathogen interaction pathways were significantly enriched in the first and third days after infection. Flavonoid biosynthesis was induced in response to late infestation (7 and 14 days post-infestation). Calmodulin, RBOH, HLC protein, RPS, PR1, and genes implicated in phytohormone crosstalk (e.g., SGT1, MYC2, PP2C, and ERF1) showed significant alterations between resistant and susceptible trees. Furthermore, salicylic acid was found to aid pine wood nematodes tolerate adverse conditions and boost reproduction, which may be significant for pine wood nematode colonization within pines. These findings provide new insights into how host defenses overcame pine wood nematode infection in the early stage, which could potentially contribute to the development of novel strategies for the control of pine wilt disease.


Assuntos
Resistência à Doença , Regulação da Expressão Gênica de Plantas , Pinus , Doenças das Plantas , Transcriptoma , Pinus/parasitologia , Pinus/genética , Animais , Doenças das Plantas/parasitologia , Doenças das Plantas/genética , Resistência à Doença/genética , Perfilação da Expressão Gênica , Tylenchoidea/fisiologia , Tylenchoidea/patogenicidade
6.
BMC Plant Biol ; 23(1): 195, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37041469

RESUMO

OBJECTIVE: There is a growing need for nematode resistant Pinaceae species plantlets to cope with the global scale degradation of coniferous forests, due to the prevalence of pine wilt disease. One of the bottlenecks that limits the commercialization of Pinaceae species plantlets is regeneration following their transfer from controlled sterile environments to the field while maintaining high survival rates. METHODS: The growth factors of somatic plantlets (SPs), such as sucrose, media, culture substrate, brassinolide and spectrum were investigated to promote the application of somatic nematode-resistant P. thunbergii plants in afforestation. RESULTS: The 1/2 WPM liquid medium, culture substrate (perlite and vermiculite =1:1), and carbohydrate (20 g/L sucrose) were effective in stimulating the growth of rooted SPs. While for unrooted SPs, 1 ug/L of brassinolide enhanced plantlet growth and rooting. And blue light (B) significantly promoted the longitudinal growth of shoots, while red light (R) was beneficial for root growth during the laboratory domestication stage. High quality SPs were obtained at a R/B ratio of 8:2. Following this acclimatization protocol, the P. thunbergii SPs could be directly transplanted to the field with a higher survival rate (85.20 %) in a forcing house. CONCLUSION: this acclimatization protocol extremely improved the survival rate of P. thunbergii SPs. Moreover, this work will contribute to enhancing the possibilities for somatic plant afforestation with Pinus species.


Assuntos
Pinus , Germinação , Taxa de Sobrevida
7.
Appl Environ Microbiol ; 89(6): e0050023, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37272792

RESUMO

Microbial assembly and metabolic potential in the subsurface critical zone (SCZ) are substantially impacted by subsurface geochemistry and hydrogeology, selecting for microbes distinct from those in surficial soils. In this study, we integrated metagenomics and geochemistry to elucidate how microbial composition and metabolic potential are shaped and impacted by vertical variations in geochemistry and hydrogeology in terrestrial subsurface sediment. A sediment core from an uncontaminated, pristine well at Oak Ridge Field Research Center in Oak Ridge, Tennessee, including the shallow subsurface, vadose zone, capillary fringe, and saturated zone, was used in this study. Our results showed that subsurface microbes were highly localized and that communities were rarely interconnected. Microbial community composition as well as metabolic potential in carbon and nitrogen cycling varied even over short vertical distances. Further analyses indicated a strong depth-related covariation of community composition with a subset of 12 environmental variables. An analysis of dissolved organic carbon (DOC) quality via ultrahigh resolution mass spectrometry suggested that the SCZ was generally a low-carbon environment, with the relative portion of labile DOC decreasing and that of recalcitrant DOC increasing along the depth, selecting microbes from copiotrophs to oligotrophs and also impacting the microbial metabolic potential in the carbon cycle. Our study demonstrates that sediment geochemistry and hydrogeology are vital in the selection of distinct microbial populations and metabolism in the SCZ. IMPORTANCE In this study, we explored the links between geochemical parameters, microbial community structure and metabolic potential across the depth of sediment, including the shallow subsurface, vadose zone, capillary fringe, and saturated zone. Our results revealed that microbes in the terrestrial subsurface can be highly localized, with communities rarely being interconnected along the depth. Overall, our research demonstrates that sediment geochemistry and hydrogeology are vital in the selection of distinct microbial populations and metabolic potential in different depths of subsurface terrestrial sediment. Such studies correlating microbial community analyses and geochemistry analyses, including high resolution mass spectrometry analyses of natural organic carbon, will further the fundamental understanding of microbial ecology and biogeochemistry in subsurface terrestrial ecosystems and will benefit the future development of predictive models on nutrient turnover in these environments.


Assuntos
Bactérias , Microbiota , Bactérias/metabolismo , Carbono/metabolismo , Tennessee
8.
Analyst ; 148(2): 366-373, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36533731

RESUMO

A 2D Cu-MOF: {[CuL(H2O)]}n (Cu-1, H2L = 3,4-ethylene dioxythiophene-2,5-dicarboxylic acid) was synthesized using the hydrothermal method. Cu-1 showed excellent solvent stability and was used to fabricate a UV ferric ion sensor. An ultra-low limit of detection (LOD) at 14.5 fM was obtained. Furthermore, N,N-dimethylformamide (DMF) as a 'turn-off' switch was introduced into the Cu-1 framework to construct another 2D Cu-MOF: {[CuL(DMF)]}n (Cu-2) by a single crystal to single crystal (SCSC) transformation method. Cu-2 lost the ability to recognize ferric ions and the switching effect of Fe3+ recognition was realized. Cyclic voltammograms (CVs) were employed to investigate this conversion process and provided a way for explaining the interaction mechanism between Cu-1 and ferric ions. We present an approach for designing and synthesizing MOFs that are suitable for ion sensing.


Assuntos
Ácidos Dicarboxílicos , Ferro , Dimetilformamida , Eletrólitos , Íons
9.
Phytopathology ; 113(3): 539-548, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36976314

RESUMO

Pine wilt disease, caused by Bursaphelenchus xylophilus, results in tremendous economic loss in conifer production every year. To disturb the host immune responses, plant pathogens secrete a mass of effector proteins that facilitate the infection process. Although several effectors of B. xylophilus have been identified, detailed mechanisms of their functions remain largely unexplored. Here, we reveal two novel B. xylophilus Kunitz effectors, named BxKU1 and BxKU2, using different infection strategies to suppress immunity in Pinus thunbergii. We found that both BxKU1 and BxKU2 could suppress PsXEG1-triggered cell death and were present in the nucleus and cytoplasm in Nicotiana benthamiana. However, they had different three-dimensional structures and various expression patterns in B. xylophilus infection. In situ hybridization experiments showed that BxKU2 was expressed in the esophageal glands and ovaries, whereas BxKU1 was only expressed in the esophageal glands of females. We further confirmed that the morbidity was significantly decreased in P. thunbergii infected with B. xylophilus when BxKU1 and BxKU2 were silenced. The silenced BxKU2I, but not BxKU1, affected the reproduction and feeding rate of B. xylophilus. Moreover, BxKU1 and BxKU2 targeted to different proteins in P. thunbergii, but they all interacted with thaumatin-like protein 4 (TLP4) according to yeast two-hybrid screening. Collectively, our study showed that B. xylophilus could incorporate two Kunitz effectors in a multilayer strategy to counter immune response in P. thunbergii, which could help us better understand the interaction between plant and B. xylophilus.


Assuntos
Pinus , Tylenchida , Animais , Xylophilus , Doenças das Plantas
10.
Int J Mol Sci ; 24(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37762682

RESUMO

Pine wilt disease (PWD) is a devastating disease that threatens pine forests worldwide, and breeding resistant pines is an important management strategy used to reduce its impact. A batch of resistant seeds of P. thunbergii was introduced from Japan. Based on the resistant materials, we obtained somatic plants through somatic embryogenesis. In this study, we performed transcriptome analysis to further understand the defense response of resistant somatic plants of P. thunbergii to PWD. The results showed that, after pine wood nematode (PWN) infection, resistant P. thunbergii stimulated more differential expression genes (DEGs) and involved more regulatory pathways than did susceptible P. thunbergii. For the first time, the alpha-linolenic acid metabolism and linoleic acid metabolism were intensively observed in pines resisting PWN infection. The related genes disease resistance protein RPS2 (SUMM2) and pathogenesis-related genes (PR1), as well as reactive oxygen species (ROS)-related genes were significantly up-expressed in order to contribute to protection against PWN inoculation in P. thunbergii. In addition, the diterpenoid biosynthesis pathway was significantly enriched only in resistant P. thunbergii. These findings provided valuable genetic information for future breeding of resistant conifers, and could contribute to the development of new diagnostic tools for early screening of resistant pine seedlings based on specific PWN-tolerance-related markers.


Assuntos
Pinus , Rabditídios , Animais , Xylophilus , Melhoramento Vegetal , Cycadopsida , Resistência à Doença/genética , Pinus/genética
11.
BMC Plant Biol ; 22(1): 216, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35473472

RESUMO

BACKGROUND: Bursaphelenchus xylophilus is the causal agent of pine wilt disease (PWD) that has caused enormous ecological and economic losses in China. The mechanism in the interaction between nematodes and pine remains unclear. Plant parasitic nematodes (PPNs) secrete effectors into host plant tissues. However, it is poorly studied that role of effector in the infection of pine wood nematode (PWN). RESULTS: We cloned, characterized and functionally validated the B. xylophilus effector BxML1, containing an MD-2-related lipid-recognition (ML) domain. This protein inhibits immune responses triggered by the molecular pattern BxCDP1 of B. xylophilus. An insitu hybridization assay demonstrated that BxML1 was expressed mainly in the dorsal glands and intestine of B. xylophilus. Subcellular localization analysis showed the presence of BxML1 in the cytoplasm and nucleus. Furthermore, number of B. xylophilus and morbidity of pine were significantly reduced in Pinus thunbergii infected with B. xylophilus when BxML was silenced. Using yeast two-hybrid (Y2H) and coimmunoprecipitation (CoIP) assays, we found that the BxML1 interacts with cyclophilin protein PtCyP1 in P. thunbergii. CONCLUSIONS: This study illustrated that BxML1 plays a critical role in the B. xylophilus-plant interaction and virulence of B. xylophilus.


Assuntos
Pinus , Tylenchida , Animais , Ciclofilinas/genética , Pinus/parasitologia , Virulência , Xylophilus
12.
Hepatology ; 74(2): 987-1002, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33619773

RESUMO

BACKGROUND AND AIMS: Acute liver damage causes hepatocyte stress and death, but in chronic liver disease impaired hepatocyte regeneration and immune cell infiltration prevents recovery. While the roles of both impaired liver regeneration and immune infiltration have been studied extensively in chronic liver diseases, the differential contribution of these factors is difficult to assess. APPROACH AND RESULTS: We combined single-cell RNA-sequencing (RNA-seq) data from healthy livers and peripheral immune cells to measure cell proportions in chronic liver diseases. Using bulk RNA-seq data from patients with early alcohol-associated hepatitis, severe AH (sAH), HCV, HCV with cirrhosis, and NAFLD, we performed gene deconvolution to predict the contribution of different cell types in each disease. Patients with sAH had the greatest change in cell composition, with increases in both periportal hepatocytes and cholangiocyte populations. Interestingly, while central vein hepatocytes were decreased, central vein endothelial cells were expanded. Endothelial cells are thought to regulate liver regeneration through WNT signaling. WNT2, important in central vein hepatocyte development, was down in sAH, while multiple other WNTs and WNT receptors were up-regulated. Immunohistochemistry revealed up-regulation of FZD6, a noncanonical WNT receptor, in hepatocytes in sAH. Immune cell populations also differed in disease. In sAH, a specific group of inflammatory macrophages was increased and distinct from the macrophage population in patients with HCV. Network and correlation analyses revealed that changes in the cell types in the liver were highly correlated with clinical liver function tests. CONCLUSIONS: These results identify distinct changes in the liver cell populations in chronic liver disease and illustrate the power of using single-cell RNA-seq data from a limited number of samples in understanding multiple different diseases.


Assuntos
Regulação da Expressão Gênica/imunologia , Hepatite Alcoólica/imunologia , Regeneração Hepática/genética , Fígado/patologia , Estudos de Casos e Controles , Análise por Conglomerados , Células Endoteliais/imunologia , Células Endoteliais/patologia , Voluntários Saudáveis , Hepatite Alcoólica/genética , Hepatite Alcoólica/patologia , Hepatócitos/imunologia , Hepatócitos/patologia , Humanos , Fígado/imunologia , Regeneração Hepática/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , RNA-Seq , Análise de Célula Única , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/imunologia
13.
BMC Neurol ; 22(1): 209, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668360

RESUMO

BACKGROUND AND PURPOSE: The present strategies regarding poststent management for cerebral venous sinus stenosis (CVSS) are inconsistent. Herein, we compared the safety and efficacy of oral anticoagulants (OACs) plus single antiplatelet therapy and dual antiplatelet therapy for CVSS poststenting. METHODS: A real-world observational study conducted from January 2009 through October 2019 enrolled patients who were diagnosed with CVSS and received stenting. Patients were divided into two groups according to the management they received poststenting. Group 1: OACs plus a single antiplatelet agent (clopidogrel 75 mg or aspirin 100 mg) and Group 2: dual antiplatelet therapy (clopidogrel 75 mg plus aspirin 100 mg). The safety (such as major or minor bleeding or venous thrombosis) and efficacy (the incidences of cerebral venous sinus restenosis, intrastent thrombosis, or stent displacement) of the two groups were compared. RESULTS: There were a total of 110 eligible patients in the final analysis, including 79 females and 31 males with a mean age of 43.42 ± 13.23 years. No major bleeding or venous thrombosis occurred in either of the two groups. Two minor bleeding events occurred in group 2 (one with subcutaneous bleeding points in both lower limbs, another with submucosal bleeding in the mouth), whereas no bleeding events occurred in Group 1. In addition, at the 1-year follow-up, one case of intraluminal restenosis and two cases of in-stent thrombi occurred in Group 2, while none occurred in Group 1. Neither stenosis at stent-adjacent segments nor stent migration was detected in either group during the 1-year following stent placement. CONCLUSION: OACs plus single antiplatelet therapy and dual antiplatelet therapy alone are both safe and efficacious management strategies after CVSS stent placement. The former may have more advantages than the latter for inhibiting intrastent thrombosis. However, further research by larger, multicenter clinical trials is needed.


Assuntos
Inibidores da Agregação Plaquetária , Trombose , Adulto , Anticoagulantes/uso terapêutico , Aspirina/efeitos adversos , Clopidogrel/uso terapêutico , Constrição Patológica/tratamento farmacológico , Quimioterapia Combinada , Feminino , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Trombose/tratamento farmacológico , Resultado do Tratamento
14.
Nanotechnology ; 33(20)2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35108696

RESUMO

Metal nanowires are attractive building blocks for next-generation plasmonic devices with high performance and compact footprint. The complex reflection coefficients of the plasmonic waveguides are crucial for estimation of the resonating, lasing, or sensing performance. By incorporating physics-guided objective functions and constraints, we propose a simple approach to convert the specific reflection problem of nanowires to a universal regression problem. Our approach is able to efficiently and reliably determine both the reflectivity and reflection phase of the metal nanowires with arbitrary geometry parameters, working environments, and terminal shapes, merging the merits of the physics-based modeling and the data-driven modeling. The results may provide valuable reference for building comprehensive datasets of plasmonic architectures, facilitating theoretical investigations and large-scale designs of nanophotonic components and devices.

15.
Environ Sci Technol ; 56(1): 451-459, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34914355

RESUMO

Although hydroxylated polybrominated diphenyl ethers (OH-BDEs) are among the most abundant natural organobromine compounds, the fundamental biological rationale for marine organisms to produce OH-BDEs remains elusive. Herein, we demonstrated that natural OH-BDEs exerted strong antibacterial activities against Escherichia coli by inhibiting enoyl-[acyl-carrier-protein] reductase (FabI), while anthropogenic OH-BDEs were inactive. Distinct from E. coli, OH-BDE-producing marine γ-proteobacteria including Marinomonas mediterranea MMB-1 (MMB-1) and Pseudoalteromonas luteoviolacea 2ta16 (Pl2ta16) exhibited resistance to 6OH-BDE47. An alternative enoyl-[acyl-carrier-protein] (ACP) reductase, FabV, was detected in all three OH-BDE-producing marine γ-proteobacteria. Thermal stability and protein affinity purification studies revealed that 6OH-BDE47 did not bind to recombinant or endogenous FabV of MMB-1 or Pl2ta16, demonstrating that FabV was the primary mechanism for OH-BDE-producing marine γ-proteobacteria to be resistant to 6OH-BDE47. To further confirm if the laboratory results were evidenced in the field, the 16S rRNA sequencing and metagenomics data from seven field-collected marine sponges were analyzed. Notably, the two Clade 4 sponges containing high concentrations of 6OH-BDE47 exhibited a distinct microbiome community structure compared to the other analyzed clades. Correspondingly, FabV was found to be selectively enriched in the same Clade 4 sponges. The merged evidence from the laboratory experiments and field studies demonstrated that 6OH-BDE47 may act as a chemical offense molecule in marine sponges.


Assuntos
Escherichia coli , Oxirredutases , Antibacterianos , Éteres Difenil Halogenados/química , RNA Ribossômico 16S
16.
Phytopathology ; 112(9): 1867-1876, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35263163

RESUMO

Phytophthora cinnamomi is an important plant pathogen that is widely distributed worldwide and has caused serious ecological damage and significant economic losses in forests and plantations in many countries. The use of plant growth-promoting rhizobacteria is an effective and environmentally friendly strategy for controlling diseases caused by P. cinnamomi. In this study, we investigated the antagonistic mechanism of Pseudomonas aurantiaca ST-TJ4 against P. cinnamomi through different antagonistic approaches, observations of mycelial morphology, study of mycelial metabolism, and identification of antagonistic substances. The results showed that Pseudomonas aurantiaca ST-TJ4 was able to significantly inhibit mycelial growth, causing mycelial deformation and disrupting internal cell structures. Additionally, pathogen cell membranes were damaged by ST-TJ4, and mycelial cell content synthesis was disrupted. Ultraperformance liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry analyses showed that phenazine compounds and 2-undecanone were the main antagonistic components. The ammonia produced by the ST-TJ4 strain also contributed to the inhibition of the growth of P. cinnamomi. In conclusion, our results confirm that Pseudomonas aurantiaca ST-TJ4 can inhibit P. cinnamomi through multiple mechanisms and can be used as a biological control agent for various plant diseases caused by P. cinnamomi.


Assuntos
Phytophthora , Compostos Orgânicos Voláteis , Fenazinas/metabolismo , Fenazinas/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Pseudomonas , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/farmacologia
17.
Phytopathology ; 112(6): 1226-1234, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35476587

RESUMO

Ectomycorrhizal fungi (EMFs) form symbioses with plant roots to promote nutrient uptake by plants but it is controversial as to whether they induce disease resistance in plants. Here, we inoculated pine seedlings with Sphaeropsis sapinea, which was presymbiotic with the EMF Hymenochaete sp. Rl, and the mycorrhizal helper bacterium (MHB) Bacillus pumilus HR10, which promotes the formation of Pinus thunbergia-Hymenochaete sp. Rl mycorrhizae. The results showed that inoculation with Hymenochaete sp. Rl, B. pumilus HR10, and the consortium significantly reduced pine shoot blight disease caused by S. sapinea. After inoculation with pathogenic fungi, callose deposition was significantly increased in needles of pine seedlings inoculated with Hymenochaete sp. Rl, B. pumilus HR10, and the consortium, together with an increase in enzymatic and nonenzymatic systemic antioxidant activity as well as early priming for upregulated expression of PR3 and PR5 genes. Our findings suggest that ectomycorrhizal colonization enhances the resistance of pine seedlings to Sphaeropsis shoot blight by triggering a systemic defense response and that interactions between EMFs and MHBs are essential for mycorrhizal-induced disease resistance.


Assuntos
Bacillus pumilus , Basidiomycota , Micorrizas , Pinus , Bactérias , Basidiomycota/fisiologia , Resistência à Doença , Micorrizas/fisiologia , Pinus/microbiologia , Doenças das Plantas , Raízes de Plantas/microbiologia , Plântula/microbiologia
18.
J Thromb Thrombolysis ; 53(4): 911-925, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34985685

RESUMO

None of studies are available on the predictive ability of white matter lesions (WMLs) among patent foramen ovale (PFO), atherosclerotic cerebral small vessel disease (aCSVD) and cerebral venous thrombosis (CVT). Herein, we aimed to uncover the difference of the WML patterns among the three disease entities in a real-world setting to provide clinical references for predicting probable WML etiologies. We retrospectively reviewed data from consecutive patients with imaging-confirmed PFO, aCSVD, or CVT enrolled from 2014 through 2020. WMLs presented on fluid-attenuated inversion recovery (FLAIR) maps were compared among the three groups based on visual evaluation, Fazekas and modified Scheltens scales. Propensity score matching (PSM) was implemented to correct age and hypertension differences among groups. A total of 401 patients were entered into final analysis, including PFO (n = 112, 46.5 ± 12.8 years), aCSVD (n = 177, 61.6 ± 11.8 years) and CVT (n = 112, 37.4 ± 11.4 years) groups. In this study, WMLs occurred in all of the involved patients in the three groups (100%), which were independent to age, symptom onset and disease durations. On visual evaluation, PFO-WMLs were multiple spots distributed asymmetrically around bilateral subcortex and peri-ventricles. aCSVD-WMLs were dots or sheets distributed symmetrically in subcortex and peri-ventricles, and often coexisted with lacunar infarctions. CVT-WMLs were cloud-like around bilateral peri-ventricles, and enabled to attenuate after recanalization. Fazekas and modified Scheltens scores of PFO-WML vs. aCSVD-WML were significantly different even after being matched by 1:2 PSM (all p < 0.05), meaning that the WML burden in aCSVD was considerably heavier than that in PFO. WML patterns induced by PFO, aCSVD and CVT were obviously different, and were therefore of great clinical significance to preliminarily predict and differentiate the three diseases entities.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Forame Oval Patente , Trombose Intracraniana , Trombose Venosa , Substância Branca , Encéfalo , Doenças de Pequenos Vasos Cerebrais/patologia , Forame Oval Patente/complicações , Forame Oval Patente/diagnóstico por imagem , Humanos , Estudos Retrospectivos , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
19.
Neurol Sci ; 43(2): 1087-1096, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34106367

RESUMO

PURPOSE: To analyze the characteristics of acute ischemic stroke (AIS) resulting from moyamoya disease (MMD) and intracranial large artery atherosclerotic stenosis (LAS). METHOD: This real-world case control study enrolled imaging-confirmed AIS patients owing to MMD or LAS hospitalized from January 2015 through September 2020 consecutively. The features of risk factors, peripheral blood, and imaging presentations were compared between the two cohorts. RESULTS: A total of 191 eligible patients entered into final analysis, including 70 cases with MMD stroke and 121 with LAS stroke. LAS stroke vs. MMD stroke, the ratios of hyperlipidemia, hypertension, diabetes, and hyperhomocysteinemia were higher in the former (65.3 vs.12.9%, 65.3% vs. 4.3%, 39.7% vs. 2.9%, and 43.8% vs.12.9%; all p < 0.01) as well as baseline plasma arachidonic acid (AA) and adenosine diphosphate (ADP)-stimulated maximum platelet aggregation rates (75.3% vs. 60.8% and 73.1% vs.64.9%, respectively, all p < 0.01), which were positively correlated with triglycerides and cholesterol levels, blood glucose, age, and platelet counts (all p < 0.01). Classical watershed infarction (WSI) accounted for 87.14% in MMD stroke and 40.49% in LAS stroke, respectively (p < 0.01). Almost all of the patients with LAS showed plaques in arterial walls on CTA maps and non-homogeneous thickening with irregular luminal narrowing on HRMRI, while plaques were seldom found in MMD besides homogeneous thickening with regular luminal narrowing. CONCLUSIONS: Differing from LAS stroke, MMD stroke mainly presents with WSI and does not feature with platelet hyper-aggregation and fragmentation of ulcer plaque. Whereby, focusing on perfusion improvement rather than antiplatelets and statins may be the predominant step in MMD-stroke correction.


Assuntos
Aterosclerose , Isquemia Encefálica , AVC Isquêmico , Doença de Moyamoya , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Estudos de Casos e Controles , Constrição Patológica , Humanos , Doença de Moyamoya/complicações , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem
20.
Appl Opt ; 61(20): 5916-5925, 2022 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-36255830

RESUMO

An optical imaging system often has problems of high complexity and low energy transmittance to compensate for aberrations. Here we propose a method to correct aberrations by coupling an optical subsystem with a digital subsystem. Specifically, in the global optimization process, the two subsystems correct their respective, easily handled aberrations so that the final imaging aberration is minimized. We design simple lenses with this method and assess imaging quality. In addition, we conduct a tolerance analysis for the proposed method and verify the effectiveness of deconvolution using a spatially varying point spread function (SVPSF) in the actual imaging process. Simulation results show the superiority of the proposed method compared with the conventional design and the feasibility of simplifying the optical system. Experimental results prove the effectiveness of deconvolution using SVPSF.

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