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Culture has a profound impact on preventive measures during the COVID-19 pandemic. Previous research has revealed that collectivism is associated with more effective responses to COVID-19 on the national or regional level. However, the impact of different components of collectivist orientation on vaccine attitudes remains insufficiently explored on the individual level. Two survey studies conducted in August 2021 in mainland China consistently found that individual-level horizontal collectivist orientation, rather than vertical collectivist orientation, was linked with more favourable vaccine attitudes. Specifically, Study 1 (N = 731) indicated that horizontal collectivist orientation was positive associated with vaccination intention indirectly via risk perception, and horizontal collectivist orientation was also positively associated with vaccination persuasion both directly and indirectly via risk perception. Study 2 (N = 1481), employing multilevel modelling, demonstrated that the link between horizontal collectivist orientation and confidence in vaccines remained robust regardless of provincial-level variations in socioeconomic development and cultural tightness. These findings convergently suggest that the positive vaccine attitudes among mainland Chinese are primarily driven by an amplified risk perception due to concern for others, rather than submission to authority.
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INTRODUCTION: To compare the real-world effectiveness of a third dose of mRNA-1273 versus a third dose of BNT162b2 against breakthrough COVID-19 hospitalizations among adults aged ≥ 65 years who completed a primary series of an mRNA-based COVID-19 vaccine (regardless of which primary series was received). MATERIALS AND METHODS: This observational comparative vaccine effectiveness (VE) study was conducted using administrative claims data from the US HealthVerity database (September 22, 2021, to August 31, 2022). A third dose of mRNA-1273 versus BNT162b2 was assessed for preventing COVID-19 hospitalizations and medically attended COVID-19 among adults aged ≥ 65 years. Inverse probability of treatment weighting was applied to balance baseline characteristics between vaccine groups. Incidence rates from patient-level data and hazard ratios (HRs) with 95 % confidence intervals (CIs) using weighted Cox proportional hazards models were calculated to estimate relative VE for each outcome. RESULTS: Overall, 94,587 and 92,377 individuals received a third dose of mRNA-1273 and BNT162b2, respectively. Among the weighted population, the median age was 69 years (interquartile range, 66-74), 53 % were female, and 46 % were commercially insured. COVID-19 hospitalization rates per 1000 person-years (PYs) were 5.61 (95 % CI, 5.13-6.09) for mRNA-1273 and 7.06 (95 % CI, 6.54-7.57) for BNT162b2 (HR, 0.82; 0.69-0.98). Medically attended COVID-19 rates per 1000 PYs (95 % CI) were 95.05 (95 % CI, 93.03-97.06) for mRNA-1273 and 106.55 (95 % CI, 104.53-108.57) for BNT162b2 (HR, 0.93; 0.89-0.98). CONCLUSIONS: Results from this observational comparative VE database study provide evidence that among older adults, a third dose of mRNA-1273 was more effective in preventing breakthrough COVID-19 hospitalization and medically attended COVID-19 infection compared with a third dose of BNT162b2.
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INTRODUCTION: Recent data have shown elevated infection rates in several subpopulations at risk of SARS-CoV-2 infection and COVID-19, including immunocompromised (IC) individuals. Previous research suggests that IC persons have reduced risks of hospitalization and medically attended COVID-19 with two doses of mRNA-1273 (SpikeVax; Moderna) compared to two doses of BNT162b2 (Comirnaty; Pfizer/BioNTech). The main objective of this retrospective cohort study was to compare real-world effectiveness of third doses of mRNA-1273 versus BNT162b2 at multiple time points on occurrence of COVID-19 hospitalization and medically attended COVID-19 among IC adults in the United States (US). METHODS: This retrospective, observational comparative effectiveness study identified patients from the US HealthVerity database from December 11, 2020, through August 31, 2022. Medically attended SARS-CoV-2 infections and hospitalizations were assessed following a three-dose mRNA-1273 versus BNT162b2 regimen. Inverse probability weighting was applied to balance baseline confounders between vaccine groups. Relative risk (RR) and risk difference were calculated for subgroup and sensitivity analyses using a non-parametric method. RESULTS: In propensity score-adjusted analyses, receiving mRNA-1273 vs. BNT162b2 as third dose was associated with 32.4% (relative risk 0.676; 95% confidence interval 0.506-0.887), 29.3% (0.707; 0.573-0.858), and 23.4% (0.766; 0.626-0.927) lower risk of COVID-19 hospitalization after 90, 180, and 270 days, respectively. Corresponding reductions in medically attended COVID-19 were 8.4% (0.916; 0.860-0.976), 6.4% (0.936; 0.895-0.978), and 2.4% (0.976; 0.935-1.017), respectively. CONCLUSIONS: Our findings suggest a third dose of mRNA-1273 is more effective than a third dose of BNT162b2 in preventing COVID-19 hospitalization and breakthrough medically attended COVID-19 among IC adults in the US.
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Lathyrisone A (1), a diterpene with an undescribed tricyclic 6/6/6 fused carbon skeleton, along with spirolathyrisins B-D (3-5), three diterpenes with a rare [4.5.0] spirocyclic carbon skeleton, and one known compound (2) were isolated from the roots of Euphorbia lathyris. Their chemical structures were characterized by extensive spectroscopic analysis, X-ray crystallography, ECD and quantum chemistry calculation. A plausible biosynthetic pathway for compounds 1-5 was proposed, which suggested it is a competitive pathway for ingenol biosynthesis in the plant. The anti-fungal activities of these compounds were tested, especially, compound 2 showed stronger anti-fungal activities against Fusarium oxysporum and Alternaria alternata than the positive control fungicide thiophanate-methyl. The preliminary structure-activity relationship of compounds 1-5 was also discussed. These results not only expanded the chemical diversities of E. lathyris, but also provided a lead compound for the control of plant pathogens.
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Alternaria , Antifúngicos , Diterpenos , Euphorbia , Fusarium , Pruebas de Sensibilidad Microbiana , Raíces de Plantas , Euphorbia/química , Diterpenos/química , Diterpenos/farmacología , Diterpenos/aislamiento & purificación , Raíces de Plantas/química , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Relación Estructura-Actividad , Fusarium/efectos de los fármacos , Alternaria/efectos de los fármacos , Estructura Molecular , Descubrimiento de Drogas , Cristalografía por Rayos X , Relación Dosis-Respuesta a DrogaRESUMEN
Fusarium head blight caused by Fusarium graminearum is a devastating disease in wheat that seriously endangers food security and human health. Previous studies have found that the secondary metabolite phenazine-1-carboxamide produced by biocontrol bacteria inhibited F. graminearum by binding to and inhibiting the activity of histone acetyltransferase Gcn5 (FgGcn5). However, the detailed mechanism of this inhibition remains unknown. Our structural and biochemical studies revealed that phenazine-1-carboxamide (PCN) binds to the histone acetyltransferase (HAT) domain of FgGcn5 at its cosubstrate acetyl-CoA binding site, thus competitively inhibiting the histone acetylation function of the enzyme. Alanine substitution of the residues in the binding site shared by PCN and acetyl-CoA not only decreased the histone acetylation level of the enzyme but also dramatically impacted the development, mycotoxin synthesis, and virulence of the strain. Taken together, our study elucidated a competitive inhibition mechanism of Fusarium fungus by PCN and provided a structural template for designing more potent phenazine-based fungicides.
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Proteínas Fúngicas , Fungicidas Industriales , Fusarium , Histona Acetiltransferasas , Fenazinas , Enfermedades de las Plantas , Triticum , Fusarium/metabolismo , Fusarium/efectos de los fármacos , Fusarium/genética , Fenazinas/metabolismo , Fenazinas/farmacología , Fenazinas/química , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Fungicidas Industriales/farmacología , Fungicidas Industriales/química , Fungicidas Industriales/metabolismo , Enfermedades de las Plantas/microbiología , Histona Acetiltransferasas/metabolismo , Histona Acetiltransferasas/genética , Histona Acetiltransferasas/química , Histona Acetiltransferasas/antagonistas & inhibidores , Triticum/microbiología , Sitios de Unión , AcetilaciónRESUMEN
INTRODUCTION: This study evaluated the labial and lingual cortical bone remodeling characteristics of mandibular central incisors after retraction, which remain controversial among orthodontists. METHODS: Cortical bone remodeling and central incisor movement of 33 patients (aged 23.64 ± 4.30 years) who underwent mandibular first premolar extraction and incisor retraction at the crestal (S1), midroot (S2), and apical (S3) levels were analyzed using superimposed cone-beam computed tomography images on the basis of voxel-based registration of the mandibular stable region. Multivariate linear regression was used to explore the relationships between labial bone remodeling/tooth movement (BT) ratios and factors such as the ANB angle, mandibular plane angle (Mp-SN), and incisor movement patterns. The patients were divided into 4 groups according to the lingual cortical bone remodeling condition and the relationship between posttreatment incisor roots and the original lingual cortical bone border. At the 3 levels (S1, S2, and S3), the classifications of cortical bone remodeling of the mandibular incisors were calculated; t tests were used to compare the amount of labial and lingual bone remodeling, BT ratios, and lingual bone remodeling/root over the original border (BRo) ratios. RESULTS: The mean labial BT ratios at all 3 levels were close to 1. Multivariate linear regression indicated that the tooth movement pattern negatively correlated with the BT ratio at the S2 and S3 levels (P <0.05). Lingual bone apposition occurs when the root penetrates the original lingual cortical bone border in most patients. BRo ratios can more accurately reflect the inherent remodeling ability of the lingual cortical bone than BT ratios. The mean lingual BRo ratios were (1) S1 level: mandibular left central incisor (T31), 0.87 ± 0.25 and mandibular right incisor (T41), 0.86 ± 0.25; (2) S2 level: T31, 0.81 ± 0.12 and T41, 0.80 ± 0.22; and (3) S3 level: T31, 0.76 ± 0.20 and T41, 0.83 ± 0.26. There was no significant difference between labial BT ratios and lingual BRo ratios at the S2 and S3 levels. CONCLUSIONS: The amount of labial cortical bone resorption caused by mandibular incisor retraction showed varied relationships with the amount of tooth movement. Bodily retraction may decrease the labial BT ratios at the S2 and S3 levels. Active lingual cortical bone apposition occurred when the roots penetrated the original lingual border and exhibited strong remodeling ability.
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Young breast cancer (YBC) patients often face a poor prognosis, hence it's necessary to construct a model that can accurately predict their long-term survival in early stage. To realize this goal, we utilized data from the Surveillance, Epidemiology, and End Results (SEER) databases between January 2010 and December 2020, and meanwhile, enrolled an independent external cohort from Tianjin Medical University Cancer Institute and Hospital. The study aimed to develop and validate a prediction model constructed using the Random Survival Forest (RSF) machine learning algorithm. By applying the Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis, we pinpointed key prognostic factors for YBC patients, which were used to create a prediction model capable of forecasting the 3-year, 5-year, 7-year, and 10-year survival rates of YBC patients. The RSF model constructed in the study demonstrated exceptional performance, achieving C-index values of 0.920 in the training set, 0.789 in the internal validation set, and 0.701 in the external validation set, outperforming the Cox regression model. The model's calibration was confirmed by Brier scores at various time points, showcasing its excellent accuracy in prediction. Decision curve analysis (DCA) underscored the model's importance in clinical application, and the Shapley Additive Explanations (SHAP) plots highlighted the importance of key variables. The RSF model also proved valuable in risk stratification, which has effectively categorized patients based on their survival risks. In summary, this study has constructed a well-performed prediction model for the evaluation of prognostic factors influencing the long-term survival of early-stage YBC patients, which is significant in risk stratification when physicians handle YBC patients in clinical settings.
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In this study, a novel estimation scheme is proposed for identifying extended Wiener-Hammerstein systems with hysteresis nonlinearity subject to quantised measurements. The proposed scheme is established in a self-error learning framework to achieve high-performance parameter estimation compared with classic error feedback learning estimation algorithms. Initially, the useful identification data can be extracted from contaminated system data by introducing an adaptive filter. Then, with the help of the filtered data, the identification error expression used to establish the estimator is derived. Subsequently, an online compensation estimation error variable is proposed to eliminate the effect of the regression vector on the convergence performance. A new adaptive law is designed with adaptive recursive gain, considering the compensation estimation error data and parameter initial error data. Under general persistent excitation (PE) condition, the PE condition of the regressor information is verified online, and the estimator convergence is strictly proven. Finally, the statistical results of two illustrated examples and a real-word example are provided to validate the positive features and effectiveness of the proposed estimation scheme.
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Four new diterpenoids, including three secolathyrane diterpenoids (1-3) and one lathyrane diterpenoid (4), together with seven known diterpenoids, were obtained in the shelled seeds of Euphorbia lathyris. In particular, 1-3 possess a rare split ring structure, and currently only one compound with the same skeleton has been identified in E. lathyris. Compound 4 furnishes an unprecedented oxygen bridge structure. The structures were identified using various spectral techniques, including NMR, HR-ESI-MS, single-crystal X-ray diffraction and calculated electronic circular dichroism (ECD). The biosynthetic pathway of 1-4 was inferred. Furthermore, the cytotoxic activities of all compounds (1-11) were measured on three human tumor cells. New compounds 2 and 3 showed moderate cytotoxic activities against U937 cells with IC50 values of 22.18 and 25.41 µM, respectively.
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Antineoplásicos Fitogénicos , Diterpenos , Euphorbia , Fitoquímicos , Semillas , Euphorbia/química , Diterpenos/aislamiento & purificación , Diterpenos/farmacología , Diterpenos/química , Humanos , Estructura Molecular , Semillas/química , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/aislamiento & purificación , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Línea Celular Tumoral , China , Células U937RESUMEN
A highly efficient and chemoselective approach for the divergent assembling of unsymmetrical hydrazines through an unprecedented intermolecular desulfurdioxidative N-N coupling is developed. This metal free protocol employs readily accessible N-arylhydroxylamines and N-sulfinylanilines to provide highly valuable hydrazine products with good reaction yields and excellent functional group tolerance under simple conditions. Computational studies suggest that the in situ generated O-sulfenylated arylhydroxylamine intermediate undergoes a retro-[2π+2σ] cycloaddition via a stepwise diradical mechanism to form the N-N bond and release SO2.
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Starvation therapy has shown promise as a cancer treatment, but its efficacy is often limited when used alone. In this work, a multifunctional nanoscale cascade enzyme system, named CaCO3@MnO2-NH2@GOx@PVP (CMGP), was fabricated for enhanced starvation/chemodynamic combination cancer therapy. CMGP is composed of CaCO3 nanoparticles wrapped in a MnO2 shell, with glucose oxidase (GOx) adsorbed and modified with polyvinylpyrrolidone (PVP). MnO2 decomposes H2O2 in cancer cells into O2, which enhances the efficiency of GOx-mediated starvation therapy. CaCO3 can be decomposed in the acidic cancer cell environment, causing Ca2+ overload in cancer cells and inhibiting mitochondrial metabolism. This synergizes with GOx to achieve more efficient starvation therapy. Additionally, the H2O2 and gluconic acid produced during glucose consumption by GOx are utilized by MnO2 with catalase-like activity to enhance O2 production and Mn2+ release. This process accelerates glucose consumption, reactive oxygen species (ROS) generation, and CaCO3 decomposition, promoting the Ca2+ release. CMGP can alleviate tumor hypoxia by cycling the enzymatic cascade reaction, which increases enzyme activity and combines with Ca2+ overload to achieve enhanced combined starvation/chemodynamic therapy. In vitro and in vivo studies demonstrate that CMGP has effective anticancer abilities and good biosafety. It represents a new strategy with great potential for combined cancer therapy.
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Carbonato de Calcio , Glucosa Oxidasa , Compuestos de Manganeso , Óxidos , Glucosa Oxidasa/metabolismo , Glucosa Oxidasa/química , Glucosa Oxidasa/farmacología , Compuestos de Manganeso/química , Compuestos de Manganeso/farmacología , Óxidos/química , Óxidos/farmacología , Humanos , Animales , Carbonato de Calcio/química , Carbonato de Calcio/farmacología , Carbonato de Calcio/metabolismo , Ratones , Antineoplásicos/farmacología , Antineoplásicos/química , Nanopartículas/química , Povidona/química , Povidona/farmacología , Hipoxia Tumoral/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Supervivencia Celular/efectos de los fármacos , Tamaño de la Partícula , Línea Celular Tumoral , Peróxido de Hidrógeno/metabolismo , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Propiedades de Superficie , Ratones Endogámicos BALB CRESUMEN
Neuroblastoma is the most common extracranial solid tumor of childhood. While MYCN and mutant anaplastic lymphoma kinase (ALKF1174L) cooperate in tumorigenesis, how ALK contributes to tumor formation remains unclear. Here, we used a human stem cell-based model of neuroblastoma. Mis-expression of ALKF1174L and MYCN resulted in shorter latency compared to MYCN alone. MYCN tumors resembled adrenergic, while ALK/MYCN tumors resembled mesenchymal, neuroblastoma. Transcriptomic analysis revealed enrichment in focal adhesion signaling, particularly the extracellular matrix genes POSTN and FN1 in ALK/MYCN tumors. Patients with ALK-mutant tumors similarly demonstrated elevated levels of POSTN and FN1. Knockdown of POSTN, but not FN1, delayed adhesion and suppressed proliferation of ALK/MYCN tumors. Furthermore, loss of POSTN reduced ALK-dependent activation of WNT signaling. Reciprocally, inhibition of the WNT pathway reduced expression of POSTN and growth of ALK/MYCN tumor cells. Thus, ALK drives neuroblastoma in part through a feedforward loop between POSTN and WNT signaling.
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Neuroblastoma , Proteínas Tirosina Quinasas Receptoras , Humanos , Quinasa de Linfoma Anaplásico/genética , Moléculas de Adhesión Celular , Línea Celular Tumoral , Proteína Proto-Oncogénica N-Myc/genética , Proteína Proto-Oncogénica N-Myc/metabolismo , Neuroblastoma/patología , Proteínas Tirosina Quinasas Receptoras/metabolismo , Vía de Señalización WntRESUMEN
Hematoporphyrin injection (HpD) mediated photodynamic therapy (PDT) has demonstrated efficacy in treating various types of Bowen's disease, including basal-cell carcinoma, squamous cell carcinoma, extramammary Paget's disease, and actinic keratosis. We present a case of a male patient who developed squamous cell carcinoma as a result of repeated instances of arsenic-induced keratosis on both his hands and feet. Due to the involvement of the joint in both hands, the patient declined the conventional surgical resection treatment since it could potentially impact normal physiological function. Instead, the patient chose to undergo hemoporphyrin photodynamic therapy. After the treatment, the rash was entirely eliminated and there were no restrictions in the movement of the joint. Nevertheless, a local recurrence was detected throughout the two-year monitoring period. Arsenical keratosis carries a substantial likelihood of recurring. However, we believe that hemoporphyrin photodynamic therapy is effective in treating this condition.
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Carcinoma de Células Escamosas , Hematoporfirinas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Neoplasias Cutáneas , Humanos , Masculino , Fotoquimioterapia/métodos , Carcinoma de Células Escamosas/tratamiento farmacológico , Fármacos Fotosensibilizantes/uso terapéutico , Hematoporfirinas/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Queratosis/tratamiento farmacológico , Queratosis/inducido químicamente , AncianoRESUMEN
BACKGROUND: Low-dose ionizing radiation-induced protection and damage are of great significance among radiation workers. We aimed to study the role of glutathione S-transferase Pi (GSTP1) in low-dose ionizing radiation damage and clarify the impact of ionizing radiation on the biological activities of cells. RESULTS: In this study, we collected peripheral blood samples from healthy adults and workers engaged in radiation and radiotherapy and detected the expression of GSTP1 by qPCR. We utilized γ-rays emitted from uranium tailings as a radiation source, with a dose rate of 14 µGy/h. GM12878 cells subjected to this radiation for 7, 14, 21, and 28 days received total doses of 2.4, 4.7, 7.1, and 9.4â¯mGy, respectively. Subsequent analyses, including flow cytometry, MTS, and other assays, were performed to assess the ionizing radiation's effects on cellular biological functions. In peripheral blood samples collected from healthy adults and radiologic technologist working in a hospital, we observed a decreased expression of GSTP1 mRNA in radiation personnel compared to the healthy controls. In cultured GM12878 cells exposed to low-dose ionizing radiation from uranium tailings, we noted significant changes in cell morphology, suppression of proliferation, delay in cell cycle progression, and increased apoptosis. These effects were partially reversed by overexpression of GSTP1. Moreover, low-dose ionizing radiation increased GSTP1 gene methylation and downregulated GSTP1 expression. Furthermore, low-dose ionizing radiation affected the expression of GSTP1-related signaling molecules. CONCLUSIONS: This study shows that low-dose ionizing radiation damages GM12878 cells and affects their proliferation, cell cycle progression, and apoptosis. In addition, GSTP1 plays a modulating role under low-dose ionizing radiation damage conditions. Low-dose ionizing radiation affects the expression of Nrf2, JNK, and other signaling molecules through GSTP1.
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Gutatión-S-Transferasa pi , Uranio , Adulto , Humanos , Gutatión-S-Transferasa pi/genética , Radiación Ionizante , Rayos gamma/efectos adversos , ApoptosisRESUMEN
RNA modification, especially N6-methyladenosine, 5-methylcytosine, and N7-methylguanosine methylation, participates in the occurrence and progression of cancer through multiple pathways. The function and expression of these epigenetic regulators have gradually become a hot topic in cancer research. Mutation and regulation of noncoding RNA, especially lncRNA, play a major role in cancer. Generally, lncRNAs exert tumor-suppressive or oncogenic functions and its dysregulation can promote tumor occurrence and metastasis. In this review, we summarize N6-methyladenosine, 5-methylcytosine, and N7-methylguanosine modifications in lncRNAs. Furthermore, we discuss the relationship between epigenetic RNA modification and lncRNA interaction and cancer progression in various cancers. Therefore, this review gives a comprehensive understanding of the mechanisms by which RNA modification affects the progression of various cancers by regulating lncRNAs, which may shed new light on cancer research and provide new insights into cancer therapy.
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Neoplasias , ARN Largo no Codificante , Humanos , Neoplasias/genética , Neoplasias/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/genética , Animales , Procesamiento Postranscripcional del ARNRESUMEN
BACKGROUND: Bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most serious diseases of rice, and there is a lack of bactericides for controlling this disease. We previously found parthenolide (PTL) is a potential lead for developing bactericides against Xoo, and subunit F of respiratory chain complex I (NuoF) is an important target protein of PTL. However, the binding modes of PTL with NuoF need further elucidation. RESULTS: In this study, we obtained the crystal structure of Xoo NuoEF (complex of subunit E and F of respiratory chain complex I) with a resolution of 2.36 Å, which is the first report on the protein structure of NuoEF in plant-pathogenic bacteria. The possible binding sites of PTL with NuoF (Cys105 and Cys187) were predicted with molecular docking and mutated into alanine using a base mismatch method. The mutated proteins were expressed in Escherichia coli and purified with affinity chromatography. The binding abilities of PTL with mutated proteins were investigated via pull-down assay and BIAcore analysis, which revealed that double mutation of Cys105 and Cys187 in NuoF severely affected the binding ability of PTL with NuoF. In addition, the binding modes were further simulated with combined quantum mechanical/molecular mechanical calculations, and the results indicated that PTL may have a stronger binding with Cys105 than Cys187. CONCLUSION: NuoEF protein structure of Xoo was resolved, and Cys105 and Cys187 in NuoF are important binding sites of PTL. This study further clarified the action mechanism of PTL against Xoo, and will promote the innovation of bactericides targeting Xoo complex I. © 2024 Society of Chemical Industry.
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Proteínas Bacterianas , Simulación del Acoplamiento Molecular , Sesquiterpenos , Xanthomonas , Xanthomonas/efectos de los fármacos , Xanthomonas/genética , Xanthomonas/enzimología , Xanthomonas/metabolismo , Sesquiterpenos/farmacología , Sesquiterpenos/metabolismo , Sesquiterpenos/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Complejo I de Transporte de Electrón/metabolismo , Complejo I de Transporte de Electrón/química , Complejo I de Transporte de Electrón/antagonistas & inhibidores , Complejo I de Transporte de Electrón/genética , Sitios de UniónRESUMEN
The plateau-type sodium titanate with suitable sodiation potential is a promising anode candidate for high safe and high energy density of sodium-ion batteries (SIBs). However, the poor initial Coulombic efficiency (ICE) and cyclic instability of sodium titanate are attributed to the unstable interfacial structure along with the decomposition of electrolytes, resulting in the continuous formation of solid electrolyte interface (SEI) film. To address this issue, a chemical grafting method is developed to fabricate a highly stable interface layer of inert Al2O3 on the sodium titanate anode, rendering the high ICE and excellent cycling stability. Based on theoretical calculations, NaPF6 are more likely adsorption on the Al2O3 surface and produce sodium fluoride. The formation of a thin and dense SEI film with rich sodium fluoride achieves the low interfacial resistances and charge-transfer resistances. Benefitting from our design, the obtained sodium titanate exhibits a high ICE from 67.7 % to 79.4 % and an enhanced reversible capacity from 151â mAh g-1 to 181â mAh g-1 at 20â mA g-1, along with an increase in capacity retention from 56.5 % to 80.6 % after 500 cycles. This work heralds a promising paradigm for rational regulation of interfacial stability to achieve high-performance anodes for SIBs.
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Flavonoids are ubiquitous polyphenolic compounds that play a vital role in plants' defense response and medicinal efficacy. UV-B radiation is a vital environmental regulator governing flavonoid biosynthesis in plants. Many plants rapidly biosynthesize flavonoids as a response to UV-B stress conditions. Here, we investigated the effects of flavonoid biosynthesis via UV-B irradiation in Euphorbia lathyris. We found that exposure of the E. lathyris callus to UV-B radiation sharply increased the level of one O-methyltransferase (ElOMT1) transcript and led to the biosynthesis of several methylated flavonoids. The methyltransferase ElOMT1 was expressed heterologously in E. coli, and we tested the catalytic activity of recombinant ElOMT1 with possible substrates, including caffeic acid, baicalin, and luteolin, in vitro. ElOMT1 could efficiently methylate when the hydroxyl groups were contained in the core nucleus of the flavonoid. This molecular characterization identifies a methyltransferase responsible for the chemical modification of the core flavonoid structure through methylation and helps reveal the mechanism of methylated flavonoid biosynthesis in Euphorbiaceae. This study identifies the O-methyltransferase that responds to UV-B irradiation and helps shed light on the mechanism of flavonoid biosynthesis in Euphorbia lathyris.
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Euphorbia , Euphorbia/genética , Escherichia coli/genética , Flavonoides/genética , Luteolina , Metiltransferasas/genéticaRESUMEN
BACKGROUND: Phytophthora capsici is an extremely destructive phytopathogenic oomycete that causes huge economic losses. However, due to the drug resistance risk and environmental threat of chemical fungicides, it is necessary to develop environmentally friendly biocontrol alternatives. Rhein is a major medicinal ingredient of traditional Chinese herbs, and it is widely used in the medical field. However, its inhibitory effect against phytopathogens is unknown. Herein, the antifungal spectrum of rhein and its possible action mechanism against P. capsici were investigated. RESULTS: Rhein possessed broad-spectrum antifungal activity against phytopathogens, particularly P. capsici, Phytophthora infestans, Helminthosporium maydis, and Rhizoctonia solani. Rhein inhibited the mycelial growth as well as the spore germination of P. capsici with mean 50% effective concentration (EC50 ) values of 4.68 µg mL-1 and 6.57 µg mL-1 against 117 P. capsici isolates, respectively. Rhein effectively suppressed the occurrence and spread of Phytophthora blight and significantly destroyed the cell membrane permeability and integrity of P. capsici, corroded its cell wall integrity, and damaged its morphology and ultrastructure. Moreover, rhein caused a considerable reduction in the phospholipid and cellulose contents. Genome-wide transcriptional profiling of P. capsici in response to rhein indicated significant reduction in the expression levels of genes participating in glycerolipid metabolism and starch and sucrose metabolism. Additionally, rhein strengthened the disease defense system of pepper by enhancing related enzyme activities. CONCLUSION: This study demonstrated that rhein could effectively inhibit P. capsici using multiple mechanisms of action. Rhein has the potential to be an efficient alternative to control diseases caused by P. capsici. © 2023 Society of Chemical Industry.