RESUMO
Bacterial communities in soil and rhizosphere maintain a large collection of antibiotic resistance genes (ARGs). However, few of these ARGs and antibiotic resistant bacteria (ARB) are well-characterized under traditional farming practices. Here we compared the ARG profiles of maize rhizosphere and their bulk soils using metagenomic analysis to identify the ARG dissemination and explored the potential impact of chemical fertilization on ARB. Results showed a relatively lower abundance but higher diversity of ARGs under fertilization than straw-return. Moreover, the abundance and diversity of MGEs were significantly promoted by chemical fertilizer inputs in the rhizosphere compared to bulk soil. Machine learning and bipartite networks identified three bacterial genera (Pseudomonas, Bacillus and Streptomyces) as biomarkers for ARG accumulation. Thus we cultured 509 isolates belonging to these three genera from the rhizosphere and tested their antimicrobial susceptibility, and found that multi-resistance was frequently observed among Pseudomonas isolates. Assembly-based tracking explained that ARGs and four class I integrons (LR134330, LS998783, CP065848, LT883143) were co-occurred among contigs from Pseudomonas sp. Chemical fertilizers may shape the resistomes of maize rhizosphere, highlighting that rhizosphere carried multidrug-resistant Pseudomonas isolates, which may pose a risk to animal and human health. This study adds knowledge of long-term chemical fertilization on ARG dissemination in farmland systems and provides information for decision-making in agricultural production and monitoring.
Assuntos
Agricultura , Fertilizantes , Rizosfera , Microbiologia do Solo , Zea mays , Zea mays/microbiologia , Agricultura/métodos , Bactérias , Resistência Microbiana a Medicamentos/genética , Solo/química , Genes BacterianosRESUMO
The Chinese giant salamander (Andrias davidianus), listed as an endangered species under "secondary protection" in China, faces significant threats due to ecological deterioration and the expansion of human activity. Extensive field investigations are crucial to ascertain the current status in the wild and to implement effective habitat protection measures to safeguard this species and support its population development. Traditional survey methods often fall short due to the elusive nature of the A. davidianus, presenting challenges that are time-consuming and generally ineffective. To overcome these obstacles, this study developed a real-time monitoring method that uses environmental DNA (eDNA) coupled with recombinase polymerase amplification and lateral flow strip (RPA-LFD). We designed five sets of species-specific primers and probes based on mitochondrial genome sequence alignments of A. davidianus and its close relatives. Our results indicated that four of these primer/probe sets accurately identified A. davidianus, distinguishing it from other tested caudata species using both extracted DNA samples and water samples from a tank housing an individual. This method enables the specific detection of A. davidianus genomic DNA at concentrations as low as 0.1 ng/mL within 50 min, without requiring extensive laboratory equipment. Applied in a field survey across four sites in Huangshan City, Anhui Province, where A. davidianus is known to be distributed, the method successfully detected the species at three of the four sites. The development of these primer/probe sets offers a practical tool for field surveying and monitoring, facilitating efforts in population recovery and resource conservation for A. davidianus.
Assuntos
Urodelos , Animais , Urodelos/genética , China , Espécies em Perigo de Extinção , DNA Ambiental/genética , DNA Ambiental/análise , DNA Mitocondrial/genética , Genoma MitocondrialRESUMO
A 64-year-old woman was admitted to the hospital for sudden weakness in one of her left limbs. The patient was diagnosed with acute ischemic stroke (IS) of undetermined cause and received intravenous thrombolysis. Following thrombolysis, the patient's left limb weakness improved, but she subsequently developed recurrent high fever and delirium. Further diagnostic tests revealed that she had been infected with Brucella melitensis. The patient showed significant improvement during anti-infection treatment for Brucellosis and secondary prevention treatment for IS. However, her condition unexpectedly worsened on the 44th day after admission due to a hemorrhagic stroke (HS), which required an urgent craniotomy. Immunohistochemical analysis of the hematoma sample collected during the operation showed the presence of CD4+ and CD8+ T lymphocytes surrounding the blood vessels. This case highlights the unique challenge of managing IS in brucellosis and sheds light on the potential role of T lymphocytes in the immune response related to stroke.
Assuntos
Anti-Infecciosos , Brucella melitensis , Brucelose , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicaçõesRESUMO
The mechanisms through which aging increases heart injury remain partially understood. Protein phosphorylation plays a critical regulatory role in cell survival and death. Using an unbiased phosphoproteomics approach, we aimed to identify the proteins whose phosphorylation could be causatively related to aging-related cardiomyocyte apoptosis and elucidate the underlying mechanisms. Comparative phosphoproteomics was conducted on cardiac tissues obtained from young (8 weeks) and aged (24 months) mice. Our findings revealed that the Mammalian Target of Rapamycin phosphorylation at T1262 (mTORT1262) was reduced in the aging heart. Immunohistochemical and Western blot analyses confirmed these findings in aging myocardia and D-galactose-induced senescent AC16 cardiomyocytes. In hypoxia/reoxygenation cardiomyocytes, mTORT1262 phosphorylation deficiency (mTORT1262A, lentivirus-mediated transfection) inhibited AKT1, suppressed NF-κB, activated FOXO1/3a signaling, and ultimately exacerbated apoptosis. Conversely, mTORT1262 pseudophosphorylation (mTORT1262E) exhibited opposite effects. Through bioinformatics and CO-IP, purinergic receptor P2X4 (P2X4R) was found to be the possible receptor responsible for mTORT1262 phosphorylation. Knockdown of P2X4R increased apoptosis, whereas its overexpression decreased it. In senescent cardiomyocytes, P2X4R expression and mTORT1262 and AKT1S473 phosphorylation were reduced, NF-κB signaling was suppressed, and FOXO1/3a signaling was activated. We demonstrated that P2X4R downregulation and the subsequent reduction of mTORT1262 phosphorylation is a novel mechanism contributing to cardiomyocyte apoptosis in aging hearts. The P2X4R-mTOR-AKT1 signaling pathway represents a potential therapeutic target against accelerated cardiac injury in aging.
Assuntos
Miócitos Cardíacos , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Miócitos Cardíacos/metabolismo , Fosforilação , Serina-Treonina Quinases TOR/metabolismo , Apoptose , Envelhecimento , MamíferosRESUMO
OBJECTIVE: To determine the association of D-dimer to albumin ratio (DAR) with major adverse cardiovascular events (MACE) after percutaneous coronary intervention (PCI) in ischaemic heart failure patients with diabetes mellitus. DESIGN: A retrospective observational cohort study. SETTING: Single centre in Beijing, China, conducted at one of the largest cardiology centres in China. PARTICIPANTS: From June 2017 to June 2019, 3707 patients with heart failure and concomitant multiple vessel disease undergoing elective PCI were screened. A total 1021 of patients were enrolled after exclusion and the follow-up period was up to 36 months. PRIMARY AND SECONDARY OUTCOME MEASURES: The MACE was the primary measured outcome. The secondary outcomes were all-cause mortality, non-fatal myocardial infarction and any revascularisation. METHODS: These participants were grouped according to DAR tertiles. The cumulative incidence functions, Cox regression, restricted cubic spline and receiver operating characteristic curves were used to determine the association between DAR and outcomes. The subgroup analysis was also performed. RESULTS: After follow-up, MACE occurred in 404 (39.6%) participants. The cumulative hazards curve manifested significant differences in MACE, all-cause mortality and any revascularisation (log-rank test: all p<0.001). In adjusted models, DAR was an independent risk factor of MACE (tertile 2: HR 1.82, 95% CI 1.37 to 2.42; tertile 3: HR 1.74, 95% CI 1.28 to 2.36) and all-cause mortality (tertile 2: HR 2.04, 95% CI 1.35 to 3.11; tertile 3: HR 1.89, 95% CI 1.20 to 2.98). The optimal cut-off of DAR was 1.2. In the stratified analysis, sex, age, hypertension, hypercholesterolaemia, total revascularisation and any interfered vessel did not affect the independent predictive ability. CONCLUSION: Higher DAR was independently associated with MACE and all-cause mortality after PCI in ischaemic heart failure patients with diabetes mellitus.
Assuntos
Diabetes Mellitus , Produtos de Degradação da Fibrina e do Fibrinogênio , Insuficiência Cardíaca , Intervenção Coronária Percutânea , Humanos , Albuminas/análise , Diabetes Mellitus/congênito , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/terapia , Hipertensão , Estudos RetrospectivosRESUMO
Hyperphosphatemia or severe acute respiratory syndrome coronavirus 2 (SARSCoV2) infection can promote cardiovascular adverse events in patients with chronic kidney disease. Hyperphosphatemia is associated with elevated inflammation and sterol regulatory element binding protein 2 (SREBP2) activation, but the underlying mechanisms in SARSCoV2 that are related to cardiovascular disease remain unclear. The present study aimed to elucidate the role of excess inorganic phosphate (PI) in SARSCoV2 N proteininduced NLRP3 inflammasome activation and the underlying mechanisms in vascular smooth muscle cells (VSMCs). The expression levels of SARSCoV2 N protein, SREBP cleavageactivating protein (SCAP), mature Nterminal SREBP2, NLRP3, procaspase1, cleaved caspase1, IL1ß and IL18 were examined by western blotting. The expression levels of SREBP2, HMGCoA reductase, HMGCS1, low density lipoprotein receptor, proprotein convertase subtilisin/kexin type 9 (PCSK9), SREBP1c, fatty acid synthase, stearyl coenzyme A desaturase 1, acetylCoA carboxylase α and ATPcitrate lyase were determined by reverse transcriptionquantitative PCR. The translocation of SCAP or NLRP3 from the endoplasmic reticulum to the Golgi was detected by confocal microscopy. The results showed that excess PI promoted SCAPSREBP and NLRP3 complex translocation to the Golgi, potentially leading to NLRP3 inflammasome activation and lipogenic gene expression. Furthermore, PI amplified SARSCoV2 N proteininduced inflammation via the SCAPSREBP pathway, which facilitates NLRP3 inï¬ammasome assembly and activation. Inhibition of phosphate uptake with phosphonoformate sodium alleviated NLRP3 inflammasome activation and reduced SREBPmediated lipogenic gene expression in VSMCs stimulated with PI and with SARSCoV2 N protein overexpression. Inhibition of SREBP2 or small interfering RNAinduced silencing of SREBP2 effectively suppressed the effect of PI and SARSCoV2 N protein on NLRP3 inflammasome activation and lipogenic gene expression. In conclusion, the present study identified that PI amplified SARSCoV2 N proteininduced NLRP3 inflammasome activation and lipogenic gene expression via the SCAPSREBP signaling pathway.
Assuntos
COVID-19 , Hiperfosfatemia , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pró-Proteína Convertase 9/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , SARS-CoV-2/metabolismo , Fosfatos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Transdução de Sinais , InflamaçãoRESUMO
BACKGROUND: Bacterial membrane vesicles (BMVs) are novel vehicles of antibiotic resistance gene (ARG) transfer in Gram-negative bacteria, but their role in the spread of ARGs in Gram-positive bacteria has not been defined. The purpose of this study was to evaluate the role of MVs in the transmission of antimicrobial resistance in Gram-positive bacteria. METHODS: A linezolid-resistant Enterococcus faecalis CQ20 of swine origin was selected as the donor strain. Linezolid-susceptible E. faecalis SC032 of human origin, Enterococcus faecium BM4105 and Escherichia coli were selected as recipient strains. The presence of plasmids (pCQ20-1 and pCQ20-2) and an optrA-carrying transposon Tn6674 in CQ20, MVs and vesiculants was verified by WGS or PCR. MVs were isolated with density gradient centrifugation, and MV-mediated transformation was performed to assess the horizontal transferability of MVs. The MICs for CQ20 and its vesiculants were determined by the broth microdilution method. RESULTS: CQ20-derived MVs (CQ20-MV) were isolated, and PCR identified the presence of two plasmids and the optrA gene in the CQ20-MVs. MV-mediated transformation to E. faecalis SC032 and E. faecium BM4105 was successfully performed, and the WGS data also showed that both plasmids pCQ20-1 and pCQ20-2 and optrA-carrying transposon Tn6674 were transferred to E. faecalis SC032 and E. faecium BM4105, but failed for E. coli. Additionally, vesiculants that had acquired ARGs still had the ability to spread these genes via MVs. CONCLUSIONS: To our knowledge, this is the first report of MV-mediated co-transfer of ARG-carrying plasmids and transposons in the Gram-positive bacterium E. faecium.
Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Humanos , Animais , Suínos , Antibacterianos/farmacologia , Linezolida , Enterococcus faecalis , Escherichia coli/genética , Farmacorresistência Bacteriana/genética , Plasmídeos/genética , Testes de Sensibilidade Microbiana , Cromossomos , Infecções por Bactérias Gram-Positivas/veterinária , Infecções por Bactérias Gram-Positivas/microbiologiaRESUMO
Effects of microplastics (MPs) and nanoplastics (NPs) on the spread of antibiotic resistance genes (ARGs) in soil-plant systems are still unclear. To investigate the spread and mechanisms of ARGs from soil to lettuce, lettuce was exposed to soil spiked with two environmentally relevant concentrations of polystyrene MPs (100 µm) and NPs (100 nm). Results showed that microorganisms that carried ARGs in soil were increased after exposure to MPs/NPs, which led to an increase in ARGs in roots. NPs were absorbed by roots and can be transported to leaves. Analysis of transcriptomics, proteomics and metabolomics indicated that high concentration of NPs regulated the expression of related genes and proteins and improved the accumulation of flavonoids in the lettuce, therefore decreased the abundance of microorganisms that contained ARGs. Our work emphasizes the size and dose influences of MPs and NPs on the spread of ARGs from soil to plant.
Assuntos
Plásticos , Poliestirenos , Microplásticos , Lactuca , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Solo , Genes BacterianosRESUMO
Engineered nanoparticles (ENPs) and nanoplastics (NPs) are typical nanoparticles in terrestrial environments. Till now, few studies have compared their toxicity and mechanism to plants. Here we investigated the effects of CuO, nZVI ENPs and polystyrene (PS) NPs on lettuce growth, metabolic functions, and microbial community structure. Results showed that low concentrations of nanoparticles decreased root biomass and promoted photosynthetic indicators, whereas increased reactive oxygen species (ROS) were detected in roots exposed to high concentrations of nanoparticles. High-dose CuO ENP exposure significantly raised the MDA content by 124.6 % compared to CK, causing the most severe membrane damage in the roots among the three types of nanoparticles. Although linoleic acid metabolism was down-regulated, the roots alleviated CuO stress by up-regulating galactose metabolism. Uptake of PS by roots similarly caused ROS production and activated the oxidative stress system by altering amino acid and vitamin metabolism. Faster microbial responses to nanoparticles were observed in the nZVI and PS networks. The root toxicity was indirectly mediated by ion release, NP uptake, or ROS generation, ultimately impacting root cell metabolism, rhizospheric microorganism and plant growth. These findings provide theoretical basis for assessing environmental impact of nanoparticles and their possible ecological risks.
Assuntos
Lactuca , Nanopartículas , Lactuca/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Microplásticos/metabolismo , Nanopartículas/toxicidade , Nanopartículas/química , Poliestirenos/toxicidade , Poliestirenos/metabolismoRESUMO
Background: Pseudochironomini is a relatively small and poorly-studied tribe of subfamily Chironominae (Diptera, Chironomidae). New information: Pseudochironomusruthae Andersen & Baranov sp. nov. is described and figured, based on a single male collected in a light trap at Matadero, Dominican Republic. The species can be separated from its congeners by the combination of the following characters: wing without dark bands, dorsocentrals in partly double row and apex of superior volsella rounded. The species is the first Pseudochironomus species to be formally recorded and described from the Caribbean. In addition, a new record of Manoapahayokeensis Jacobsen & Perry, 2002 from the Dominican Republic is given. One specimen was DNA-barcoded and the barcode is given.