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1.
Proc Natl Acad Sci U S A ; 121(28): e2402407121, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38959045

RESUMEN

Trade-offs between evolutionary gain and loss are prevalent in nature, yet their genetic basis is not well resolved. The evolution of insect resistance to insecticide is often associated with strong fitness costs; however, how the fitness trade-offs operates remains poorly understood. Here, we show that the mitogen-activated protein kinase (MAPK) pathway and its upstream and downstream actors underlie the fitness trade-offs associated with insecticide resistance in the whitefly Bemisia tabaci. Specifically, we find a key cytochrome P450 gene CYP6CM1, that confers neonicotinoids resistance to in B. tabaci, is regulated by the MAPKs p38 and ERK through their activation of the transcription factor cAMP-response element binding protein. However, phosphorylation of p38 and ERK also leads to the activation of the transcription repressor Cap "n" collar isoform C (CncC) that negatively regulates exuperantia (Ex), vasa (Va), and benign gonial cell neoplasm (Bg), key genes involved in oogenesis, leading to abnormal ovary growth and a reduction in female fecundity. We further demonstrate that the transmembrane G protein-coupled receptor (GPCR) neuropeptide FF receptor 2 (NPFF2) triggers the p38 and ERK pathways via phosphorylation. Additionally, a positive feedback loop between p38 and NPFF2 leads to the continuous activation of the MAPK pathways, thereby constitutively promoting neonicotinoids resistance but with a significant reproductive cost. Collectively, these findings provide fundamental insights into the role of cis-trans regulatory networks incurred by GPCR-MAPK signaling pathways in evolutionary trade-offs and applied knowledge that can inform the development of strategies for the sustainable pest control.


Asunto(s)
Hemípteros , Proteínas de Insectos , Resistencia a los Insecticidas , Sistema de Señalización de MAP Quinasas , Receptores Acoplados a Proteínas G , Animales , Hemípteros/genética , Hemípteros/metabolismo , Resistencia a los Insecticidas/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Femenino , Insecticidas/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/genética
2.
PLoS Genet ; 20(2): e1011163, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38377137

RESUMEN

Neonicotinoid insecticides, which target insect nicotinic acetylcholine receptors (nAChRs), have been widely and intensively used to control the whitefly, Bemisia tabaci, a highly damaging, globally distributed, crop pest. This has inevitably led to the emergence of populations with resistance to neonicotinoids. However, to date, there have been no reports of target-site resistance involving mutation of B. tabaci nAChR genes. Here we characterize the nAChR subunit gene family of B. tabaci and identify dual mutations (A58T&R79E) in one of these genes (BTß1) that confer resistance to multiple neonicotinoids. Transgenic D. melanogaster, where the native nAChR Dß1 was replaced with BTß1A58T&R79E, were significantly more resistant to neonicotinoids than flies where Dß1 were replaced with the wildtype BTß1 sequence, demonstrating the causal role of the mutations in resistance. The two mutations identified in this study replace two amino acids that are highly conserved in >200 insect species. Three-dimensional modelling suggests a molecular mechanism for this resistance, whereby A58T forms a hydrogen bond with the R79E side chain, which positions its negatively-charged carboxylate group to electrostatically repulse a neonicotinoid at the orthosteric site. Together these findings describe the first case of target-site resistance to neonicotinoids in B. tabaci and provide insight into the molecular determinants of neonicotinoid binding and selectivity.


Asunto(s)
Hemípteros , Insecticidas , Receptores Nicotínicos , Animales , Receptores Nicotínicos/genética , Insecticidas/farmacología , Hemípteros/genética , Drosophila melanogaster , Neonicotinoides/farmacología , Mutación
3.
Proteomics ; : e2300393, 2024 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-38430206

RESUMEN

Prostate cancer (PCa) is one of the leading causes of cancer morbidity and mortality in men. Metastasis is the main cause of PCa-associated death. Recent evidence indicated a significant reduction in PCa mortality associated with higher ω-3 polyunsaturated fatty acids (PUFAs) consumption. However, the underlying mechanisms remained elusive. In this study, we applied global acetylome profiling to study the effect of fatty acids treatment. Results indicated that oleic acid (OA, monounsaturated fatty acid, MUFA, 100 µM) elevates while EPA (eicosapentaenoic acid, 100 µM) reduces the acetyl-CoA level, which alters the global acetylome. After treatment, two crucial cell motility regulators, PFN1 and FLNA, were found with altered acetylation levels. OA increased the acetylation of PFN1 and FLNA, whereas EPA decreased PFN1 acetylation level. Furthermore, OA promotes while EPA inhibits PCa migration and invasion. Immunofluorescence assay indicated that EPA impedes the formation of lamellipodia or filopodia through reduced localization of PFN1 and FLNA to the leading edge of cells. Therefore, perturbed acetylome may be one critical step in fatty acid-affected cancer cell motility. This study provides some new insights into the response of ω-3 PUFAs treatment and a better understanding of cancer cell migration and invasion modulation.

4.
J Biol Chem ; 299(2): 102903, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36642179

RESUMEN

Members of glycosyltransferase family 75 (GT75) not only reversibly catalyze the autoglycosylation of a conserved arginine residue with specific NDP-sugars but also exhibit NDP-pyranose mutase activity that reversibly converts specific NDP-pyranose to NDP-furanose. The latter activity provides valuable NDP-furanosyl donors for glycosyltransferases and requires a divalent cation as a cofactor instead of FAD used by UDP-D-galactopyranose mutase. However, details of the mechanism for NDP-pyranose mutase activity are not clear. Here we report the first crystal structures of GT75 family NDP-pyranose mutases. The novel structures of GT75 member MtdL in complex with Mn2+ and GDP, GDP-D-glucopyranose, GDP-L-fucopyranose, GDP-L-fucofuranose, respectively, combined with site-directed mutagenesis studies, reveal key residues involved in Mn2+ coordination, substrate binding, and catalytic reactions. We also provide a possible catalytic mechanism for this unique type of NDP-pyranose mutase. Taken together, our results highlight key elements of an enzyme family important for furanose biosynthesis.


Asunto(s)
Actinobacteria , Glicosiltransferasas , Transferasas Intramoleculares , Galactosa/metabolismo , Glicosiltransferasas/química , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Transferasas Intramoleculares/química , Transferasas Intramoleculares/genética , Transferasas Intramoleculares/metabolismo , Mutagénesis Sitio-Dirigida , Actinobacteria/enzimología
5.
J Biol Chem ; 299(5): 104695, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37044213

RESUMEN

Pulmonary fibrosis is a progressive lung disease characterized by macrophage activation. Asbestos-induced expression of nicotinamide adenine dinucleotide phosphate hydrogen oxidase 4 (NOX4) in lung macrophages mediates fibrotic progression by the generation of mitochondrial reactive oxygen species (ROS), modulating mitochondrial biogenesis, and promoting apoptosis resistance; however, the mechanism(s) by which NOX4 localizes to mitochondria during fibrosis is not known. Here, we show that NOX4 localized to the mitochondrial matrix following asbestos exposure in lung macrophages via direct interaction with TIM23. TIM23 and NOX4 interaction was found in lung macrophages from human subjects with asbestosis, while it was absent in mice harboring a conditional deletion of NOX4 in lung macrophages. This interaction was localized to the proximal transmembrane region of NOX4. Mechanistically, TIM23 augmented NOX4-induced mitochondrial ROS and metabolic reprogramming to oxidative phosphorylation. Silencing TIM23 decreased mitochondrial ROS and oxidative phosphorylation. These observations highlight the important role of the mitochondrial translocase TIM23 interaction with NOX4. Moreover, this interaction is required for mitochondrial redox signaling and metabolic reprogramming in lung macrophages.


Asunto(s)
Macrófagos Alveolares , Mitocondrias , NADPH Oxidasa 4 , Animales , Humanos , Ratones , Fibrosis , Macrófagos Alveolares/metabolismo , Mitocondrias/metabolismo , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , Especies Reactivas de Oxígeno/metabolismo
6.
Plant Mol Biol ; 114(3): 49, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38642182

RESUMEN

Rapeseed, an important oil crop, relies on robust seedling emergence for optimal yields. Seedling emergence in the field is vulnerable to various factors, among which inadequate self-supply of energy is crucial to limiting seedling growth in early stage. SUGAR-DEPENDENT1 (SDP1) initiates triacylglycerol (TAG) degradation, yet its detailed function has not been determined in B. napus. Here, we focused on the effects of plant growth during whole growth stages and energy mobilization during seedling establishment by mutation in BnSDP1. Protein sequence alignment and haplotypic analysis revealed the conservation of SDP1 among species, with a favorable haplotype enhancing oil content. Investigation of agronomic traits indicated bnsdp1 had a minor impact on vegetative growth and no obvious developmental defects when compared with wild type (WT) across growth stages. The seed oil content was improved by 2.0-2.37% in bnsdp1 lines, with slight reductions in silique length and seed number per silique. Furthermore, bnsdp1 resulted in lower seedling emergence, characterized by a shrunken hypocotyl and poor photosynthetic capacity in the early stages. Additionally, impaired seedling growth, especially in yellow seedlings, was not fully rescued in medium supplemented with exogenous sucrose. The limited lipid turnover in bnsdp1 was accompanied by induced amino acid degradation and PPDK-dependent gluconeogenesis pathway. Analysis of the metabolites in cotyledons revealed active amino acid metabolism and suppressed lipid degradation, consistent with the RNA-seq results. Finally, we proposed strategies for applying BnSDP1 in molecular breeding. Our study provides theoretical guidance for understanding trade-off between oil accumulation and seedling energy mobilization in B. napus.


Asunto(s)
Brassica napus , Plantones , Plantones/genética , Semillas/genética , Cotiledón/genética , Lípidos , Aminoácidos/metabolismo , Brassica napus/metabolismo
7.
Cancer Sci ; 115(5): 1476-1491, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38475938

RESUMEN

Liver cancer is the sixth most common cancer and the third leading cause of cancer-related death globally. Despite efforts being made in last two decades in cancer diagnosis and treatment, the 5-year survival rate of liver cancer remains extremely low. TRIM21 participates in cancer metabolism, glycolysis, immunity, chemosensitivity and metastasis by targeting various substrates for ubiquitination. TRIM21 serves as a prognosis marker for human hepatocellular carcinoma (HCC), but the mechanism by which TRIM21 regulates HCC tumorigenesis and progression remains elusive. In this study, we demonstrated that TRIM21 protein levels were elevated in human HCC. Elevated TRIM21 expression was associated with HCC progression and poor survival. Knockdown of TRIM21 in HCC cell lines significantly impaired cell growth and metastasis and enhanced sorafenib-induced toxicity. Mechanistically, we found that knockdown of TRIM21 resulted in cytosolic translocation and inactivation of YAP. At the molecular level, we further identified that TRIM21 interacted and induced ubiquitination of MST1, which resulted in MST1 degradation and YAP activation. Knockdown of MST1 or overexpression of YAP reversed TRIM21 knockdown-induced impairment of HCC growth and chemosensitivity. Taken together, the current study demonstrates a novel mechanism that regulates the Hippo pathway and reveals TRM21 as a critical factor that promotes growth and chemoresistance in human HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Ribonucleoproteínas , Transducción de Señal , Animales , Femenino , Humanos , Masculino , Ratones , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Ribonucleoproteínas/metabolismo , Ribonucleoproteínas/genética , Sorafenib/farmacología , Sorafenib/uso terapéutico , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Ubiquitinación , Proteínas Señalizadoras YAP/metabolismo , Proteínas Señalizadoras YAP/genética
8.
Small ; 20(34): e2401464, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38616766

RESUMEN

Organic-inorganic hybrid linear and nonlinear optical (NLO) materials have received increasingly wide spread attention in recent years. Herein, the first hybrid noncentrosymmetric (NCS) borophosphate, (C5H6N)2B2O(HPO4)2 (4PBP), is rationally designed and synthesized by a covalent-linkage strategy. 4-pyridyl-boronic acid (4 PB) is considered as a bifunctional unit, which may effectively improve the optical properties and stability of the resultant material. On the one hand, 4 PB units are covalently linked with PO3(OH) groups via strong B-O-P connections, which significantly enhances the thermal stability of 4PBP (decomposition at 321, vs lower 200 °C of most of hybrid materials). On the other hand, the planar π-conjugated C5H6N units and their uniform layered arrangements represent large structural anisotropy and hyperpolarizability, achieving the largest birefringence (0.156 @ 546 nm) in the reported borophosphates and a second-harmonic generation response (0.7 × KDP). 4PBP also exhibits a wide transparency range (0.27-1.50 µm). This work not only provides a promising birefringent material, but also offers a practical covalent-attachment strategy for the rational design of new high-performance optical materials.

9.
Opt Express ; 32(3): 3804-3816, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38297593

RESUMEN

In biomedical studies, Mueller matrix polarimetry is gaining increasing attention because it can comprehensively characterize polarization-related vectorial properties of the sample, which are crucial for microstructural identification and evaluation. For backscattering Mueller matrix polarimetry, there are two photon coordinate selection conventions, which can affect the following Mueller matrix parameters calculation and information acquisition quantitatively. In this study, we systematically analyze the influence of photon coordinate system selection on the backscattering Mueller matrix polarimetry. We compare the Mueller matrix elements in the right-handed-nonunitary and non-right-handed-unitary coordinate systems, and specifically deduce the changes of Mueller matrix polar decomposition, Mueller matrix Cloude decomposition and Mueller matrix transformation parameters widely used in backscattering Mueller matrix imaging as the photon coordinate system varied. Based on the theoretical analysis and phantom experiments, we provide a group of photon coordinate system transformation invariants for backscattering Mueller matrix polarimetry. The findings presented in this study give a crucial criterion of parameters selection for backscattering Mueller matrix imaging under different photon coordinate systems.

10.
Opt Lett ; 49(9): 2273-2276, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691697

RESUMEN

As a complex anisotropic medium, variation in birefringence within biological tissues is closely associated with numerous physiological behaviors and phenomena. In this Letter, we propose a polarization feature fusion method and corresponding polarimetric parameters, which exhibit excellent performance of capturing the birefringence dynamic variation process in complex anisotropic media. By employing the feature fusion method, we combine and transform polarization basis parameters (PBPs) to derive fused polarization feature parameters (FPPs) with explicit expressions. Subsequently, we conduct Monte Carlo (MC) simulation to demonstrate the effectiveness of the proposed FPPs from two variation dimensions of birefringence direction θ and modulus Δn. Leveraging mathematical modeling and linear transformations, we investigate and abstract their response patterns concerning θ and Δn. Finally, the experiments confirm that the FPPs show superior adaptability and interpretability in characterizing the birefringence dynamic process of turbid media. The findings presented in this study provide new, to the best of our knowledge, methodological insights of information extraction for computational polarimetry in biomedical research.

11.
Opt Lett ; 49(18): 5135-5138, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39270248

RESUMEN

Recently, virtual staining techniques have attracted more and more attention, which can help bypass the chemical staining process of traditional histopathological examination, saving time and resources. Meanwhile, as an emerging tool to characterize specific tissue structures in a label-free manner, the Mueller matrix microscopy can supplement more structural information that may not be apparent in bright-field images. In this Letter, we propose the Mueller matrix guided generative adversarial networks (MMG-GAN). By integrating polarization information provided by the Mueller matrix microscopy, the MMG-GAN enables the effective transformation of input H&E-stained images into corresponding Masson trichrome (MT)-stained images. The experimental results demonstrate the accuracy of the generated images by MMG-GAN and reveal the potential for more stain transformation tasks by incorporating the Mueller matrix polarization information, laying the foundation for future polarimetry-assisted digital pathology.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Coloración y Etiquetado , Humanos , Microscopía de Polarización/métodos
12.
Opt Lett ; 49(12): 3356-3359, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38875619

RESUMEN

Mueller matrix microscopy can provide comprehensive polarization-related optical and structural information of biomedical samples label-freely. Thus, it is regarded as an emerging powerful tool for pathological diagnosis. However, the staining dyes have different optical properties and staining mechanisms, which can put influence on Mueller matrix microscopic measurement. In this Letter, we quantitatively analyze the polarization enhancement mechanism from hematoxylin and eosin (H&E) staining in multispectral Mueller matrix microscopy. We examine the influence of hematoxylin and eosin dyes on Mueller matrix-derived polarization characteristics of fibrous tissue structures. Combined with Monte Carlo simulations, we explain how the dyes enhance diattenuation and linear retardance as the illumination wavelength changed. In addition, it is demonstrated that by choosing an appropriate incident wavelength, more visual Mueller matrix polarimetric information can be observed of the H&E stained tissue sample. The findings can lay the foundation for the future Mueller matrix-assisted digital pathology.


Asunto(s)
Coloración y Etiquetado , Microscopía de Polarización/métodos , Eosina Amarillenta-(YS)/química , Método de Montecarlo , Hematoxilina , Humanos
13.
Chem Res Toxicol ; 37(1): 42-56, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-38091573

RESUMEN

The chemokine receptor CXCR3 is functionally pleiotropic, not only recruiting immune cells to the inflamed liver but also mediating the pathological process of cholestatic liver injury (CLI). However, the mechanism of its involvement in the CLI remains unclear. Both alpha-naphthylisothiocyanate (ANIT) and triptolide are hepatotoxicants that induce CLI by bile acid (BA) dysregulation, inflammation, and endoplasmic reticulum (ER)/oxidative stress. Through molecular docking, CXCR3 is a potential target of ANIT and triptolide. Therefore, this study aimed to investigate the role of CXCR3 in ANIT- and triptolide-induced CLI and to explore the underlying mechanisms. Wild-type mice and CXCR3-deficient mice were administered with ANIT or triptolide to compare CLI, BA profile, hepatic recruitment of IFN-γ/IL-4/IL-17+CD4+T cells, IFN-γ/IL-4/IL-17+iNKT cells and IFN-γ/IL-4+NK cells, and the expression of ER/oxidative stress pathway. The results showed that CXCR3 deficiency ameliorated ANIT- and triptolide-induced CLI. CXCR3 deficiency alleviated ANIT-induced dysregulated BA metabolism, which decreased the recruitment of IFN-γ+NK cells and IL-4+NK cells to the liver and inhibited ER stress. After triptolide administration, CXCR3 deficiency ameliorated dysregulation of BA metabolism, which reduced the migration of IL-4+iNKT cells and IL-17+iNKT cells and reduced oxidative stress through inhibition of Egr1 expression and AKT phosphorylation. Our findings suggest a detrimental role of CXCR3 in ANIT- and triptolide-induced CLI, providing a promising therapeutic target and introducing novel mechanisms for understanding cholestatic liver diseases.


Asunto(s)
1-Naftilisotiocianato , Colestasis , Diterpenos , Fenantrenos , Animales , Ratones , 1-Naftilisotiocianato/toxicidad , 1-Naftilisotiocianato/metabolismo , Interleucina-17/toxicidad , Interleucina-17/metabolismo , Interleucina-17/uso terapéutico , Interleucina-4/toxicidad , Interleucina-4/metabolismo , Interleucina-4/uso terapéutico , Simulación del Acoplamiento Molecular , Hígado/metabolismo , Colestasis/inducido químicamente , Ácidos y Sales Biliares , Compuestos Epoxi
14.
Faraday Discuss ; 251(0): 509-522, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-38766758

RESUMEN

The exploration of the fundamental formation mechanisms of polycyclic aromatic hydrocarbons (PAHs) is crucial for the understanding of molecular mass growth processes leading to two- and three-dimensional carbonaceous nanostructures (nanosheets, graphenes, nanotubes, buckyballs) in extraterrestrial environments (circumstellar envelopes, planetary nebulae, molecular clouds) and combustion systems. While key studies have been conducted exploiting traditional, high-temperature mechanisms such as the hydrogen abstraction-acetylene addition (HACA) and phenyl addition-dehydrocyclization (PAC) pathways, the complexity of extreme environments highlights the necessity of investigating chemically diverse mass growth reaction mechanisms leading to PAHs. Employing the crossed molecular beams technique coupled with electronic structure calculations, we report on the gas-phase synthesis of phenanthrene (C14H10)-a three-ring, 14π benzenoid PAH-via a phenylethynyl addition-cyclization-aromatization mechanism, featuring bimolecular reactions of the phenylethynyl radical (C6H5CC, X2A1) with benzene (C6H6) under single collision conditions. The dynamics involve a phenylethynyl radical addition to benzene without entrance barrier leading eventually to phenanthrene via indirect scattering dynamics through C14H11 intermediates. The barrierless nature of reaction allows rapid access to phenanthrene in low-temperature environments such as cold molecular clouds which can reach temperatures as low as 10 K. This mechanism constitutes a unique, low-temperature framework for the formation of PAHs as building blocks in molecular mass growth processes to carbonaceous nanostructures in extraterrestrial environments thus affording critical insight into the low-temperature hydrocarbon chemistry in our universe.

15.
Eur J Clin Microbiol Infect Dis ; 43(9): 1721-1730, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39023632

RESUMEN

PURPOSE: Acinetobacter baumannii is emerging as a pathogen that is a focus of global concern due to the frequent occurrence of the strains those are extensively resistant to antibiotics. This study was aimed to analyze the clinical and microbiological characteristics of a cohort of patients with A. baumannii bloodstream infections (BSIs) in western China. METHODS: A retrospective study of the patients at West China Hospital of Sichuan University with A. baumannii BSIs between Jan, 2018 and May, 2023 was conducted. Antimicrobial susceptibility of A. baumannii isolates was tested by microdilution broth method. Whole-genome sequencing and genetic analysis were also performed for these isolates. RESULTS: Among the 117 patients included, longer intensive care unit stay, higher mortality, and more frequent invasive procedures and use of more than 3 classes of antibiotics were observed among the carbapenem-resistant A. baumannii (CRAB)-infected group (n = 76), compared to the carbapenem-susceptible A. baumannii (CSAB)-infected group (n = 41, all P ≤ 0.001). Twenty-four sequence types (STs) were determined for the 117 isolates, and 98.7% (75/76) of CRAB were identified as ST2. Compared to non-ST2 isolates, ST2 isolates exhibited higher antibiotic resistance, and carried more resistance and virulence genes (P < 0.05). In addition, 80 (68.4%) isolates were CRISPR-positive, showed higher antibiotic susceptibility, and harbored less resistance and virulence genes, in comparison to CRISPR-negative ones (P < 0.05). Phylogenetic clustering based on coregenome SNPs indicated a sporadic occurrence of clonal transmission. CONCLUSION: Our findings demonstrate a high frequency of ST2 among A. baumannii causing BSIs, and high antibiotic susceptibility of non-ST2 and CRISPR-positive isolates. It is necessary to strengthen the surveillance of this pathogen.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Antibacterianos , Bacteriemia , Pruebas de Sensibilidad Microbiana , Humanos , Acinetobacter baumannii/genética , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/aislamiento & purificación , Acinetobacter baumannii/clasificación , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/tratamiento farmacológico , Masculino , Estudios Retrospectivos , Femenino , Persona de Mediana Edad , Anciano , China/epidemiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacteriemia/microbiología , Bacteriemia/epidemiología , Secuenciación Completa del Genoma , Farmacorresistencia Bacteriana Múltiple/genética , Adulto , Anciano de 80 o más Años , Carbapenémicos/farmacología
16.
Environ Sci Technol ; 58(17): 7469-7479, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38557082

RESUMEN

Trivalent arsenicals such as arsenite (AsIII) and methylarsenite (MAsIII) are thought to be ubiquitous in flooded paddy soils and have higher toxicity than pentavalent forms. Fungi are widely prevalent in the rice rhizosphere, and the latter is considered a hotspot for As uptake. However, few studies have focused on alleviating As toxicity in paddy soils using fungi. In this study, we investigated the mechanism by which the protein TaGlo1, derived from the As-resistant fungal strain Trichoderma asperellum SM-12F1, mitigates AsIII and MAsIII toxicity in paddy soils. Taglo1 gene expression in Escherichia coli BL21 conferred strong resistance to AsIII and MAsIII, while purified TaGlo1 showed a high affinity for AsIII and MAsIII. Three cysteine residues (Cys13, Cys18, and Cys71) play crucial roles in binding with AsIII, while only two (Cys13 and Cys18) play crucial roles for MAsIII binding. TaGlo1 had a stronger binding strength for MAsIII than AsIII. Importantly, up to 90.2% of the homologous TaGlo1 proteins originate from fungi by GenBank searching. In the rhizospheres of 14 Chinese paddy soils, Taglo1 was widely distributed and its gene abundance increased with porewater As. This study highlights the potential of fungi to mitigate As toxicity and availability in the soil-rice continuum and suggests future microbial strategies for bioremediation.


Asunto(s)
Contaminantes del Suelo , Suelo , Suelo/química , Arsenitos , Microbiología del Suelo , Oryza
17.
Phys Chem Chem Phys ; 26(26): 18321-18332, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38912536

RESUMEN

The biphenyl molecule (C12H10) acts as a fundamental molecular backbone in the stereoselective synthesis of organic materials due to its inherent twist angle causing atropisomerism in substituted derivatives and in molecular mass growth processes in circumstellar environments and combustion systems. Here, we reveal an unconventional low-temperature phenylethynyl addition-cyclization-aromatization mechanism for the gas-phase preparation of biphenyl (C12H10) along with ortho-, meta-, and para-substituted methylbiphenyl (C13H12) derivatives through crossed molecular beams and computational studies providing compelling evidence on their formation via bimolecular gas-phase reactions of phenylethynyl radicals (C6H5CC, X2A1) with 1,3-butadiene-d6 (C4D6), isoprene (CH2C(CH3)CHCH2), and 1,3-pentadiene (CH2CHCHCHCH3). The dynamics involve de-facto barrierless phenylethynyl radical additions via submerged barriers followed by facile cyclization and hydrogen shift prior to hydrogen atom emission and aromatization to racemic mixtures (ortho, meta) of biphenyls in overall exoergic reactions. These findings not only challenge our current perception of biphenyls as high temperature markers in combustion systems and astrophysical environments, but also identify biphenyls as fundamental building blocks of complex polycyclic aromatic hydrocarbons (PAHs) such as coronene (C24H12) eventually leading to carbonaceous nanoparticles (soot, grains) in combustion systems and in deep space thus affording critical insight into the low-temperature hydrocarbon chemistry in our universe.

18.
Environ Res ; 252(Pt 2): 118919, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38631468

RESUMEN

The escalation of global water pollution due to emerging pollutants has gained significant attention. To address this issue, catalytic peroxymonosulfate (PMS) activation technology has emerged as a promising treatment approach for effectively decontaminating a wide range of pollutants. Recently, modified biochar has become an increasingly attractive as PMS activator. Metal-heteroatom-co-doped biochar (MH-BC) has emerged as a promising catalyst that can provide enhanced performance over heteroatom-doped and metal-doped biochar due to the synergism between metal and heteroatom in promoting PMS activation. Therefore, this review aims to discuss the fabrication pathways (i.e., internal vs external doping and pre-vs post-modification) and key parameters (i.e., source of precursors, synthesis methods, and synthesis conditions) affecting the performance of MH-BC as PMS activator. Subsequently, an overview of all the possible PMS activation pathways by MH-BC is provided. Subsequently, Also, the detection, identification, and quantification of several reactive species (such as, •OH, SO4•-, O2•-, 1O2, and high valent oxo species) generated in the catalytic PMS system by MH-BC are also evaluated. Lastly, the underlying challenges associated with poor stability, the lack of understanding regarding the interaction between metal and heteroatom during PMS activation and quantification of radicals in multi-ROS system are also deliberated.


Asunto(s)
Carbón Orgánico , Restauración y Remediación Ambiental , Peróxidos , Carbón Orgánico/química , Peróxidos/química , Restauración y Remediación Ambiental/métodos , Catálisis , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Metales/química
19.
Environ Res ; 252(Pt 4): 119055, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38710429

RESUMEN

Application of biochar and inoculation with specific microbial strains offer promising approaches for addressing atrazine contamination in agricultural soils. However, determining the optimal method necessitates a comprehensive understanding of their effects under similar conditions. This study aimed to evaluate the effectiveness of biochar and Paenarthrobacter sp. AT5, a bacterial strain known for its ability to degrade atrazine, in reducing atrazine-related risks to soybean crops and influencing bacterial communities. Both biochar and strain AT5 significantly improved atrazine degradation in both planted and unplanted soils, with the most substantial reduction observed in soils treated with strain AT5. Furthermore, bioaugmentation with strain AT5 outperformed biochar in enhancing soybean growth, photosynthetic pigments, and antioxidant defenses. While biochar promoted higher soil bacterial diversity compared to strain AT5, the latter selectively enriched specific bacterial populations. Additionally, soil inoculated with strain AT5 displayed a notable increase in the abundance of key genes associated with atrazine degradation (trzN, atzB, and atzC), surpassing the effects observed with biochar addition, thus highlighting its effectiveness in mitigating atrazine risks in soil.


Asunto(s)
Atrazina , Biodegradación Ambiental , Carbón Orgánico , Glycine max , Herbicidas , Microbiología del Suelo , Contaminantes del Suelo , Atrazina/toxicidad , Glycine max/microbiología , Glycine max/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Herbicidas/toxicidad , Suelo/química , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/metabolismo
20.
Surg Endosc ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138685

RESUMEN

BACKGROUND: The prognosis comparison between endoscopic therapy + partial splenic embolization (PSE) and Hassab's operation is unclear in the treatment of esophageal variceal bleeding in patients with liver cirrhosis. This study aimed to compare the outcome of endoscopic therapy + PSE (EP) with a combination of splenectomy + pericardial devascularization procedure, known as Hassab's operation (SH) for esophageal variceal bleeding in patients with liver cirrhosis with hypersplenism. METHODS: We enrolled 328 patients, including 125 and 203 patients who underwent EP and SH, respectively. Each group consisted of 110 patients after propensity score matching (PSM). Subsequently, we recorded and analyzed bleeding episodes and mortality in 6 months and 1, 2, and 5 years after therapies. RESULTS: The median follow-up time in the EP and SH groups was 53 and 64 months, respectively. Bleeding incidence 6 months after therapies in the EP group was lower than that in the SH group (1.8% vs. 10.0%, P = 0.010). Additionally, complications in the perioperative period were not significantly different (0% vs. 3.6%, P = 0.008). However, the bleeding rate between the two groups was not significantly different at 1, 2, and 5 years after therapies (7.3% vs. 12.7%, P = 0.157; 10.9% vs. 16.4%, P = 0.205; 30.6% vs. 31.8%, P = 0.801), as well as mortality rate (4.5% vs 7.3%, P = 0.571). CONCLUSION: Compared with SH therapy, the bleeding rate 6 months after EP therapy was lower, but the long-term bleeding rate was similar.

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