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BACKGROUND: Glehnia littoralis is a medicinal and edible plant species having commercial value and has several hundred years of cultivation history. Polyploid breeding is one of the most important and fastest ways to generate novel varieties. To obtain tetraploids of G. littoralis in vitro, colchicine treatment was given to the seeds and then were screened based on morphology, flow cytometry, and root tip pressing assays. Furthermore, transcriptome analysis was performed to identity the differentially expressed genes associated with phenotypic changes in tetraploid G. littoralis. RESULTS: The results showed that 0.05% (w/v) colchicine treatment for 48 h was effective in inducing tetraploids in G. littoralis. The tetraploid G. littoralis (2n = 4x = 44) was superior in leaf area, leaf thickness, petiole diameter, SPAD value (Chl SPAD), stomatal size, epidermal tissues thickness, palisade tissues thickness, and spongy tissues thickness to the diploid ones, while the stomatal density of tetraploids was significantly lower. Transcriptome sequencing revealed, a total of 1336 differentially expressed genes (DEGs) between tetraploids and diploids. Chromosome doubling may lead to DNA content change and gene dosage effect, which directly affects changes in quantitative traits, with changes such as increased chlorophyll content, larger stomata and thicker tissue of leaves. Several up-regulated DEGs were found related to growth and development in tetraploid G. littoralis such as CKI, PPDK, hisD and MDP1. KEGG pathway enrichment analyses showed that most of DEGs were enriched in metabolic pathways. CONCLUSIONS: This is the first report of the successful induction of tetraploids in G. littoralis. The information presented in this study facilitate breeding programs and molecular breeding of G. littoralis varieties.
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Perfilação da Expressão Gênica , Fenótipo , Tetraploidia , Transcriptoma , Colchicina/farmacologia , Caryophyllales/genética , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/anatomia & histologiaRESUMO
BACKGROUND: Chronic pain was associated with a higher risk of mental disorders (e.g., depression and anxiety). However, the role of 24-h movement behaviors in the association remains unclear. METHODS: A total of 72,800 participants with accelerometer data and free of mental disorders from the UK Biobank were analyzed. The compositional mediation model and isotemporal substitution model were used to explore the associations between chronic pain, 24-h movement behaviors, and the incidence of overall mental disorders, depression, and anxiety. RESULTS: With a median follow-up of 13.36 years, participants with chronic pain had a higher rate of incident overall mental disorders (hazard ratio (HR): 1.281, 95% confidence interval (CI): 1.219 to 1.344), anxiety (HR: 1.391, 95% CI: 1.280 to 1.536), and depression (HR: 1.703, 95% CI: 1.551 to 1.871). Increased sedentary behavior (SB) and reduced moderate-to-vigorous physical activity (MVPA) caused by chronic pain both increased the risk of mental disorders. Twenty-four-hour movement behaviors explained the relationship between chronic pain and overall mental disorders, depression, and anxiety by 10.77%, 5.70%, and 6.86%, respectively. Interaction effects were found between MVPA and chronic pain when predicting the incidence of depression and between MVPA, sleep (SLP), and chronic pain when predicting the incidence of mental disorders. People with chronic pain would recommend at least 0.5 h per day of MVPA and 7 h per day of SLP and restricting SB below 11.5 h per day. CONCLUSIONS: Twenty-four-hour movement behaviors played a significant mediating role in the association between chronic pain and mental disorders. Individuals with chronic pain should engage in more MVPA, less sedentary behavior, and have 7-h sleep per day.
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Dor Crônica , Transtornos Mentais , Humanos , Dor Crônica/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Transtornos Mentais/epidemiologia , Incidência , Reino Unido/epidemiologia , Adulto , Estudos de Coortes , Idoso , Comportamento Sedentário , Exercício Físico/fisiologia , Ansiedade/epidemiologia , Depressão/epidemiologiaRESUMO
Hydrogen sulfide (H2S) is a gaseous signaling molecule reported to play multiple roles in fruit ripening. However, the molecular mechanisms underlying H2S-mediated delay in fruit ripening remain to be established. Here, the gene encoding a WRKY transcription factor, WRKY71, was identified as substantially upregulated in H2S-treated tomato (Solanum lycopersicum) via transcriptome profiling. The expression of WRKY71 was negatively associated with that of CYANOALANINE SYNTHASE1 (CAS1). Transient and stable genetic modification experiments disclosed that WRKY71 acts as a repressor of the tomato ripening process. CAS1 appears to play an opposite role, based on the finding that the ripening process was delayed in the cas1 mutant and accelerated in CAS1-OE tomatoes. Dual-luciferase reporter assay, yeast one-hybrid, electrophoretic mobility shift assay, and transient transformation experiments showed that WRKY71 bound to the CAS1 promoter and suppressed its activation. Moreover, the persulfidation of WRKY71 enhanced its binding ability to the CAS1 promoter. Data from luciferase complementation and Y2H assays confirmed that WRKY71 interacts with a BOI-related E3 ubiquitin-protein ligase 3 (BRG3) and is ubiquitinated in vitro. Further experiments showed that modification of BRG3 via persulfidation at Cys206 and Cys212 led to reduced ubiquitination activity. Our findings support a model whereby BRG3 undergoes persulfidation at Cys206 and Cys212, leading to reduced ubiquitination activity and decreased interactions with the WRKY71 transcript, with a subsequent increase in binding activity of the persulfidated WRKY71 to the CAS1 promoter, resulting in its transcriptional inhibition and thereby delayed ripening of tomatoes. Our collective findings provide insights into a mechanism of H2S-mediated regulation of tomato fruit ripening.
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Solanum lycopersicum , Solanum lycopersicum/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Frutas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Etilenos/metabolismoRESUMO
The cultivated diploid Brassica oleracea is an important vegetable crop, but the genetic basis of its domestication remains largely unclear in the absence of high-quality reference genomes of wild B. oleracea. Here, we report the first chromosome-level assembly of the wild Brassica oleracea L. W03 genome (total genome size, 630.7 Mb; scaffold N50, 64.6 Mb). Using the newly assembled W03 genome, we constructed a gene-based B. oleracea pangenome and identified 29 744 core genes, 23 306 dispensable genes, and 1896 private genes. We re-sequenced 53 accessions, representing six potential wild B. oleracea progenitor species. The results of the population genomic analysis showed that the wild B. oleracea populations had the highest level of diversity and represents the most closely related population to modern-day horticultural B. oleracea. In addition, the WUSCHEL gene was found to play a decisive role in domestication and to be involved in cauliflower and broccoli curd formation. We also illustrate the loss of disease-resistance genes during selection for domestication. Our results provide new insights into the domestication of B. oleracea and will facilitate the future genetic improvement of Brassica crops.
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Brassica , Produtos Agrícolas , Domesticação , Genoma de Planta , Brassica/genética , Produtos Agrícolas/genética , Cromossomos de Plantas/genéticaRESUMO
BACKGROUND: Fried food has increased in popularity worldwide. However, deep frying can increase the production of peroxidative toxins in food, which might be harmful to fetal development. The antioxidative effect of vitamin D3 (VD3) has been reported previously. OBJECTIVES: This study aimed to explore how maternal VD3 supplementation in an oxidized-oil diet during gestation affects fetal antioxidative ability and development. METHODS: Pregnant mice were randomly assigned into 3 groups: Control group (diet with fresh soybean oil), OSO group [diet with oxidized soybean oil (OSO)], and OSOV group (diet with OSO and 10,000 IU/Kg VD3). Mice were fed with the corresponding diet during gestation. On day 16.5 of gestation, the placenta and fetus were harvested to analyze antioxidative status. RESULTS: Maternal oxidized-oil diet during gestation significantly reduced placental vessel abundance, labyrinth zone area, and fetal body weight. However, dietary VD3 supplementation prevented these negative effects of oxidized-oil diet. Maternal intake of oxidized-oil diet increased serum concentrations of malondialdehyde, total-nitric oxide synthase, and inducible nitric oxide synthase, whereas VD3 supplementation showed a protection effect on it. Additionally, maternal VD3 supplementation increased the levels of antioxidative enzymes and the nuclear translocation of nuclear factor erythroid 2-related factor 2 (NRF2), thereby protecting placenta and fetus from apoptosis and oxidative stress caused by an oxidized-oil diet. The gene expression and protein levels of a fatty acid transporter solute carrier family 27 member 1 in the fetal liver were increased by maternal VD3 supplementation under oxidized-oil diet. Notably, NRF2 could be co-immunoprecipitated with the VD receptor in the placenta. CONCLUSIONS: Maternal VD3 supplementation could protect fetus from oxidized-oil diet induced developmental impairment by alleviating oxidative stress in the placenta and fetus through the VD receptor/NRF2 pathway, at least partially. Thus, ensuring adequate levels of VD3 through supplementation is often critical during pregnancy.
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The growing appreciation of immune cell-cell interactions within disease environments has led to extensive efforts to develop immunotherapies. However, characterizing complex cell-cell interfaces in high resolution remains challenging. Thus, technologies leveraging therapeutic-based modalities to profile intercellular environments offer opportunities to study cell-cell interactions with molecular-level insight. We introduce photocatalytic cell tagging (PhoTag) for interrogating cell-cell interactions using single-domain antibodies (VHHs) conjugated to photoactivatable flavin-based cofactors. Following irradiation with visible light, the flavin photocatalyst generates phenoxy radical tags for targeted labeling. Using this technology, we demonstrate selective synaptic labeling across the PD-1/PD-L1 axis in antigen-presenting cell-T cell systems. In combination with multiomics single-cell sequencing, we monitored interactions between peripheral blood mononuclear cells and Raji PD-L1 B cells, revealing differences in transient interactions with specific T cell subtypes. The utility of PhoTag in capturing cell-cell interactions will enable detailed profiling of intercellular communication across different biological systems.
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Antígeno B7-H1 , Leucócitos Mononucleares , Comunicação Celular , Flavinas , ImunoterapiaRESUMO
KEY MESSAGE: Map-based cloning revealed that a mutation in a highly conserved amino acid of the CsGME gene encoding GDP-mannose 3,5-epimerase, causes the phenotype of little and wrinkled leaves in cucumbers. Leaf size is a critical determinant of plant architecture in cucumbers, yet only a few genes associated with this trait have been mapped or cloned. Here, we identified and characterized a mutant with little and wrinkled leaves, named lwl-1. Genetic analysis revealed that the phenotype of the lwl-1 was controlled by a single recessive gene. Through map-based cloning, the lwl-1 locus was narrowed down to a 12.22-kb region exclusively containing one fully annotated gene CsGME (CsaV3_2G004170). CsGME encodes GDP-mannose 3,5-epimerase, which is involved in the synthesis of ascorbic acid (ASA) and one of the components of pectin, RG-II. Whole-length sequencing of the 12.22 kb DNA fragment revealed the presence of only a non-synonymous mutation located in the sixth exon of CsGME in lwl-1, resulting in an amino acid alteration from Pro363 to Leu363. This mutation was unique among 118 inbred lines from cucumber natural populations. CsGME expression significantly reduced in various organs of lwl-1, accompanied by a significant decrease in ASA and pectin content in leaves. Both CsGME and Csgme proteins were localized to the cytoplasm. The mutant phenotype exhibited partial recovery after the application of exogenous boric acid. Silencing CsGME in cucumber through VIGS confirmed its role as the causal gene for lwl-1. Transcriptome profiling revealed that CsGME greatly affected the expression of genes related to the cell division process and cell plate formation. This study represents the first report to characterize and clone the CsGME in cucumber, indicating its crucial role in regulating leaf size and development.
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Carboidratos Epimerases , Mapeamento Cromossômico , Cucumis sativus , Folhas de Planta , Ácido Ascórbico/metabolismo , Carboidratos Epimerases/genética , Carboidratos Epimerases/metabolismo , Clonagem Molecular , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/enzimologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genes Recessivos , Mutação , Fenótipo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Oxanthromicin is an anthranone-type natural product isolated from Streptomyces sp. TRM 15522, which exhibits antifungal activity. However, the underlying mechanisms remain unclear. This study, therefore, aimed at investigating the mode of action of oxanthromicin against the phytopathogen Verticillium dahliae. We found that oxanthromicin substantially suppressed spore germination and mycelial growth in V. dahliae. Further, electron microscopy and staining with propidium iodide and Rhodamine 123 indicated that oxanthromicin causes cell membrane damage and induces changes in mitochondrial membrane potential. These findings suggest that oxanthromicin exhibits its antifungal activity by damaging fungal cell membranes. This discovery could potentially facilitate the development of oxanthromicin as a biological pesticide.
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Ascomicetos , Verticillium , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Doenças das Plantas/microbiologia , AntraquinonasRESUMO
GaAs nanowires (NWs) have wide application potential as near-infrared optical devices and the high-pressure strategy has been applied to modulate their crystal and electronic structures. As another typical thermodynamic parameter, temperature can also affect the optical performance of semiconductors. Here we report the excitation-wavelength-dependent photoluminescence (EWDP) in GaAs NWs under high-pressure conditions. The pressure for achieving the maximum photoluminescence (PL) intensity and bandgap transition from direct to indirect of GaAs NWs varies (1.7-2.7 GPa) with the wavelength of the incident lasers (633-473 nm). The Raman peak of GaAs NWs shifts towards higher frequency with increasing excitation wavelengths at the same high-pressure conditions, revealing the stronger heating effect induced by incident laser with the shorter wavelength. The relative temperature difference in GaAs NWs induced by two different lasers can be estimated up to 537 K, and the strong heating effect suppresses the light-emission efficiency in GaAs NWs. With increasing the pressure, the relative temperature difference presents a gradual declining trend and PL intensity presents an opposite trend, which relates to the pressure-induced suppression of nonradiative recombination in GaAs NWs. Our study provides insights into the mechanisms for the EWDP effect and an alternative route to modulate the high-pressure performance of nanodevices.
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BACKGROUND: Myocardial injury after non-cardiac surgery (MINS) is a common and serious complication in older patients. This study investigates the impact of neuromuscular block on the MINS incidence and other cardiovascular complications in the early postoperative stage of older patients undergoing laparoscopic colorectal cancer resection. METHODS: 70 older patients who underwent laparoscopic colorectal cancer resection were separated into the deep neuromuscular block group and moderate neuromuscular block group for 35 cases in each group (n = 1:1). The deep neuromuscular block group maintained train of four (TOF) = 0, post-tetanic count (PTC) 1-2, and the moderate neuromuscular block group maintained TOF = 1-2 during the operation. Sugammadex sodium was used at 2 mg/kg or 4 mg/kg for muscle relaxation antagonism at the end of surgery. The MINS incidence was the primary outcome and compared with Fisher's exact test. About the secondary outcomes, the postoperative pain was analyzed with Man-Whitney U test, the postoperative nausea and vomiting (PONV) and the incidence of cardiovascular complications were analyzed with Chi-square test, intraoperative mean artery pressure (MAP) and cardiac output (CO) ratio to baseline, length of stay and dosage of anesthetics were compared by two independent samples t-test. RESULTS: MINS was not observed in both groups. The highest incidence of postoperative cardiovascular complications was lower limbs deep vein thrombosis (14.3% in deep neuromuscular block group and 8.6% in moderate neuromuscular group). The numeric rating scale (NRS) score in the deep neuromuscular block group was lower than the moderate neuromuscular block group 72 h after surgery (0(1,2) vs 0(1,2), P = 0.018). The operation time in the deep neuromuscular block group was longer (356.7(107.6) vs 294.8 (80.0), min, P = 0.008), the dosage of propofol and remifentanil was less (3.4 (0.7) vs 3.8 (1.0), mg·kg-1·h-1, P = 0.043; 0.2 (0.06) vs 0.3 (0.07), µg·kg-1·min-1, P < 0.001), and the length of hospital stay was shorter than the moderate neuromuscular block group (18.4 (4.9) vs 22.0 (8.3), day, P = 0.028). The differences of other outcomes were not statistically significant. CONCLUSIONS: Maintaining different degrees of the neuromuscular block under TOF guidance did not change the MINS incidence within 7 days after surgery in older patients who underwent laparoscopic colorectal cancer resection. TRIAL REGISTRATION: The present study was registered in the Chinese Clinical Trial Registry (10/02/2021, ChiCTR2100043323).
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Neoplasias Colorretais , Laparoscopia , Bloqueio Neuromuscular , Complicações Pós-Operatórias , Humanos , Masculino , Feminino , Idoso , Laparoscopia/métodos , Laparoscopia/efeitos adversos , Neoplasias Colorretais/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Bloqueio Neuromuscular/métodos , Bloqueio Neuromuscular/efeitos adversos , Incidência , Idoso de 80 Anos ou mais , Traumatismos Cardíacos/epidemiologia , Traumatismos Cardíacos/etiologiaRESUMO
BACKGROUND: Savolitinib, a small molecule inhibitor, has gained approval as the inaugural medication in China that specifically targets MET kinase. Patients with advanced non-small cell lung cancer (NSCLC) who show MET exon 14 skipping now have a new and innovative treatment option available. CASE REPORT: In this case report, we describe a patient who experienced drug-induced liver injury (DILI) due to the administration of savolitinib. After being prescribed with savolitinib (400 mg per day, oral), a 73-year-old male diagnosed with stage IV NSCLC with MET exon 14 skipping mutation experienced an increase in liver enzymes and bilirubin levels according to his laboratory tests conducted one month later. Following a 14-day course of hepatoprotective medication, the liver function reverted back to its normal state. After receiving savolitinib (200 mg per day, oral) for one week, the patient was once again diagnosed with severe liver impairment. Then savolitinib was discontinued and received treatment with hepatoprotective drugs for one week. Following the restoration of normal liver function, another attempt was made to administer a small amount of savolitinib (100 mg per day, oral). Thus far, the patient has been followed up and there has been no recurrence of liver damage. Additionally, the lung CT scan revealed ongoing tumor shrinkage with no apparent indications of spreading or metastasis. The Roussel Uclaf Causality Assessment Method (RUCAM) determined that savolitinib was "highly probable" cause of DILI. Moderate-severe was determined to be the extent of DILI severity. CONCLUSION: To the best of our understanding, this is the initial instance of DILI resulting from the use of savolitinib as a standalone treatment in a real-world setting. During the administration of savolitinib, healthcare professionals should carefully consider the potential occurrence of DILI. Administering the patient with a small amount of savolitinib resulted in a remarkable response against the tumor, leading us to speculate that the effectiveness of savolitinib might be associated with its plasma concentration. Studying the pharmacokinetics and pharmacodynamics (PK/PD) of savolitinib is beneficial for tailoring and accurately prescribing the medication to each individual.
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Carcinoma Pulmonar de Células não Pequenas , Doença Hepática Induzida por Substâncias e Drogas , Neoplasias Pulmonares , Humanos , Masculino , Idoso , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Acrilamidas/efeitos adversos , Acrilamidas/uso terapêutico , Inibidores de Proteínas Quinases/efeitos adversosRESUMO
BACKGROUND: Given the increased risk of chronic diseases and comorbidity among middle-aged and older adults in China, it is pivotal to identify the disease trajectory of developing chronic multimorbidity and address the temporal correlation among chronic diseases. METHOD: The data of 15895 participants from the China Health and Retirement Longitudinal Study (CHARLS 2011 - 2018) were analyzed in the current study. Binomial tests and the conditional logistic regression model were conducted to estimate the associations among 14 chronic diseases, and the disease trajectory network analysis was adopted to visualize the relationships. RESULTS: The analysis showed that hypertension is the most prevalent disease among the 14 chronic conditions, with the highest cumulative incidence among all chronic diseases. In the disease trajectory network, arthritis was found to be the starting point, and digestive diseases, hypertension, heart diseases, and dyslipidemia were at the center, while memory-related disease (MRD), stroke, and diabetes were at the periphery of the network. CONCLUSIONS: With the chronic disease trajectory network analysis, we found that arthritis was prone to the occurrence and development of various other diseases. In addition, patients of heart diseases/hypertension/digestive disease/dyslipidemia were under higher risk of developing other chronic conditions. For patients with multimorbidity, early prevention can preclude them from developing into poorer conditions, such as stroke, MRD, and diabetes. By identifying the trajectory network of chronic disease, the results provided critical insights for developing early prevention and individualized support services to reduce disease burden and improve patients' quality of life.
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Artrite , Diabetes Mellitus , Doenças do Sistema Digestório , Dislipidemias , Cardiopatias , Hipertensão , Acidente Vascular Cerebral , Pessoa de Meia-Idade , Humanos , Idoso , Estudos Longitudinais , Aposentadoria , Qualidade de Vida , Hipertensão/epidemiologia , Cardiopatias/epidemiologia , Diabetes Mellitus/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Artrite/epidemiologia , Doença Crônica , China/epidemiologiaRESUMO
A 58-year-old woman presented with a 1-day history of abdominal pain. Abdominal CT showed an oval soft tissue density mass in the fundus of the gallbladder (red arrow), approximately 4.0 cm × 3.0 cm in size. The level of cancer antigen 199 was elevated (275.80 U/mL; normal level, 0.0-27.0 U/mL). Other tumor markers were normal including alpha fetoprotein, carcinoembryonic antigen. Abdominal magnetic resonance imaging demonstrated the mass with characteristic of mixed signals, containing marked enhanced ingredient (yellow arrow) and poor blood supply ingredient (blue arrow). Radical cholecystectomy, partial liver resection, and regional lymphadenectomy were performed. Pathological examination indicated mixed adenoneuroendocrine carcinoma, with the following immunohistochemistry results: CD56 (+) (Figure 1F), Syn (+) (Figure 1G), CK19 (+) (Figure 1H), CgA (+), MLHL (+), PMS2 (+), MSH2 (+), MSH6 (+), Ki-67 (60%+).
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Adenocarcinoma , Carcinoma Neuroendócrino , Neoplasias da Vesícula Biliar , Neoplasias Gastrointestinais , Feminino , Humanos , Pessoa de Meia-Idade , Carcinoma Neuroendócrino/diagnóstico por imagem , Carcinoma Neuroendócrino/cirurgia , Neoplasias da Vesícula Biliar/diagnóstico por imagem , Neoplasias da Vesícula Biliar/cirurgia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia , Adenocarcinoma/patologiaRESUMO
Objective To investigate the effect of Lemiancao on insomnia in the patients with depressive disorder. Methods Totally 79 patients diagnosed with both insomnia and depressive disorder from February to August in 2022 in Peking University Sixth Hospital were selected and classified into a control group(n=40) and a Lemiancao group(n=39).The Lemiancao group received routine nursing and medical treatment combined with Lemiancao training in the morning and evening every day,while the control group received routine nursing and medical treatment.The sleep status was evaluated based on the Pittsburgh sleep quality index(PSQI),insomnia severity index(ISI),and 36-item short-form health survey(SF-36) before and after treatment. Results The general information of patients showed no significant difference between the two groups(all P>0.05).After a 2-week intervention with Lemiancao training,the Lemiancao group showed lower PSQI and ISI scores and higher SF-36 score than the control group(all P<0.001). Conclusion Lemiancao training has therapeutic effects on insomnia in the patients with depressive disorder.
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Transtorno Depressivo , Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/complicações , Sono , Inquéritos Epidemiológicos , Transtorno Depressivo/complicaçõesRESUMO
Due to the accelerated appearance of antimicrobial-resistant (AMR) pathogens in clinical infections, new first-in-class antibiotics, operating via novel modes of action, are desperately needed. Brevicidine, a bacterial nonribosomally produced cyclic lipopeptide, has shown potent and selective antimicrobial activity against Gram-negative pathogens. However, before our investigations, little was known about how brevicidine exerts its potent bactericidal effect against Gram-negative pathogens. In this study, we find that brevicidine has potent antimicrobial activity against AMR Enterobacteriaceae pathogens, with MIC values ranging between 0.5 µM (0.8 mg/L) and 2 µM (3.0 mg/L). In addition, brevicidine showed potent antibiofilm activity against the Enterobacteriaceae pathogens, with the same 100% inhibition and 100% eradication concentration of 4 µM (6.1 mg/L). Further mechanistic studies showed that brevicidine exerts its potent bactericidal activity by interacting with lipopolysaccharide in the outer membrane, targeting phosphatidylglycerol and cardiolipin in the inner membrane, and dissipating the proton motive force of bacteria. This results in metabolic perturbation, including the inhibition of ATP synthesis; the inhibition of the dehydrogenation of NADH; the accumulation of reactive oxygen species in bacteria; and the inhibition of protein synthesis. Finally, brevicidine showed a good therapeutic effect in a mouse peritonitis-sepsis model. Our findings pave the way for further research on the clinical applications of brevicidine to combat prevalent infections caused by AMR Gram-negative pathogens worldwide.
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Antibacterianos , Enterobacteriaceae , Animais , Camundongos , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Bactérias , Lipopeptídeos/farmacologia , Testes de Sensibilidade Microbiana , Bactérias Gram-NegativasRESUMO
Temporally heterogeneous environments is hypothesized to correlate with greater plasticity of plants, which has rarely been supported by direct evidence. To address this issue, we subjected three species from different ranges of habitats to a first round of alternating full light and heavy shading (temporally heterogeneous light experience), constant moderate shading and full light conditions (temporally homogeneous light experiences, control) and a second round of light-gradient treatments. We measured plant performance in a series of morphological, biomass, physiological and biochemical traits at the end of each round. Compared to constant full light experience, temporally heterogeneous light conditions induced immediate active biochemical responses (in the first round) with improved late growth in biomass (during the second round); constant moderate shading experience increased photosynthetic physiological and biomass performances of plants in early response, and decreased their late growth in biomass. The karst endemic species of Kmeria septentrionalis showed greater improvement in late growth of biomass and lower decrease in biochemical performance, due to early heterogeneous experience, compared to the non-karst species of Lithocarpus glaber and the karst adaptable species of Celtis sinensis. Results suggested plants will prefer to produce morphological and physiological responses that are less reversible and more costly in the face of more reliable environmental cues at early stage in spite of decreased future growth potential, but to produce immediate biochemical responses for higher late growth potential when early environmental cues are less reliable, to avoid the loss of high costs and low profits. Typical karst species should be more able to benefit from early temporally heterogeneous experience, due to long-term adaptation to karst habitats of high environmental heterogeneity and low resource availability.
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Ecossistema , Plantas , Biomassa , Fotossíntese , Adaptação Fisiológica , Folhas de Planta/fisiologiaRESUMO
OBJECTIVES: To describe the pharmacokinetics of vancomycin in a large Chinese paediatric cohort with varying degrees of renal function and ages and to develop practical dosing guidelines. PATIENTS AND METHODS: We conducted a retrospective population pharmacokinetic study using data from paediatric patients who received vancomycin between June 2013 and June 2022. A non-linear mixed-effect modelling approach with a one-compartment model structure was applied. Monte Carlo simulations were used to stimulate an optimal dosage regimen to achieve the target of AUC24/MIC between 400 and 650. RESULTS: We analysed a total of 673 paediatric patients and 1547 vancomycin serum concentrations. Covariate analysis revealed that physiological maturation, renal function, albumin and cardiothoracic surgery (CTS) significantly affected vancomycin pharmacokinetics. The typical clearance and volume of distribution, standardized to 70 kg, were 7.75 L/h (2.3% relative standard error, RSE) and 36.2 L (1.7% RSE), respectively. Based on the model, we proposed an optimal dosing regimen that considers the patient's age and estimate glomerular filtration rate (eGFR) to achieve a target AUC24/MIC for CTS and non-CTS patients. We also found that a loading dose of 20 mg/kg can help patients with an eGFR of <60 mL/min/1.73 m2 achieve the target AUC on the first day of treatment. CONCLUSIONS: We established vancomycin pharmacokinetic parameters in Chinese paediatric patients and proposed a dosing guideline integrating eGFR, age and CTS status, potentially improving clinical outcomes and reducing nephrotoxicity risk.
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Antibacterianos , Vancomicina , Humanos , Criança , Estudos Retrospectivos , População do Leste Asiático , Testes de Sensibilidade Microbiana , Método de Monte Carlo , Rim/fisiologiaRESUMO
Magneto-plasmon sensors based on the transverse magneto-optical Kerr effect (TMOKE) have been extensively studied in recent years. In this paper, we theoretically propose a hybrid structure composed of a one-dimensional bismuth iron garnet: yttrium iron garnet (BIG: YIG) nanowire arrays and thin film stack, which is grown on an infinite thick silicon wafer. The thin film stack, from top to bottom, consists of the following layers: BIG: YIG, SiO2, and Au. By exciting the magnetic dipole resonance mode between the cylindrical nanowires and the SPP mode on the surface of the Au film, dual-channel sensing has been achieved in both visible and infrared spectra. The results demonstrate that the TMOKE response spectrum of the structure supports ultra-narrow linewidths of 0.03â nm in the visible light range and 1.54â nm in the infrared range. By changing the refractive index of the analyte, the detected sensitivity of the sensor system in visible and infrared bands is 553â nm RIU-1 and 285â nm RIU-1, and the Figure of merit (FOM) can reach up to 69125 RIU-1 and 303 RIU-1, respectively. This work provides a theoretical basis and a feasible approach for the design of dual channel gas sensors.
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Monolayer direct-band gap transition metal dichalcogenides (TMDCs) have been extensively investigated in the context of light-matter interactions. To reach strong coupling, these studies make use of external optical cavities supporting well-defined resonant modes. However, use of an external cavity might limit the scope of possible applications of such systems. Here, we demonstrate that thin films of TMDCs can themselves serve as high-quality-factor cavities due to the guided optical modes they sustain in the visible and near-infrared ranges. Making use of the prism coupling, we achieve the strong coupling between excitons and guided-mode resonances lying below the light line, and show that the thickness of TMDC membranes can be used to tune and promote photon-exciton interactions within the strong-coupling regime. Additionally, we demonstrate narrowband perfect absorption in thin TMDC films through critical coupling with guided-mode resonances. Our work not only provides a simple and intuitive picture to tame interaction of light and matter in thin TMDC films, but also suggests that these simple systems are a promising platform for realizing polaritonic and optoelectronic devices.
RESUMO
The concept of symmetry-protected bound states in the continuum (BICs) offers a simple approach to engineer metasurfaces with high-quality (Q) factors. However, traditional designs driven by symmetry-protected BICs require an extremely small perturbation parameter to obtain very large Q factors, complicating fabrication and limiting practical applications. Here, we demonstrate a BIC-driven structure composed of two coupled all-dielectric metasurfaces that enables ultrahigh-Q resonances even at large perturbations. The underlying mechanism enabling this is to merge the symmetry-protected BIC and Fabry-Pérot BIC in the parameter space by tuning the distance between the two metasurfaces, thereby altering the intrinsic radiation behavior of the isolated symmetry-protected BIC. It is found that this simple strategy results in Q factors that are three orders of magnitude higher than those with isolated-BIC configurations. Our approach provides a promising route for designing high-Q BIC nanostructures promising in exciting device applications as sensors and filters.