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1.
Int J Infect Dis ; : 107084, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38705567

RESUMEN

OBJECTIVES: We investigated how booster interval affects the risks of SARS-CoV-2 infection and Covid-19-related hospitalization and death in different age groups. METHODS: We collected data on booster receipts and Covid-19 outcomes between September 22, 2021 and February 9, 2023 for 5,769,205 North Carolina residents ≥12 years of age who had completed their primary vaccination series. We related Covid-19 outcomes to baseline characteristics and booster doses through Cox regression models. RESULTS: For adults ≥65 years of age, boosting every 9 months was associated with proportionate reductions (compared with no boosting) of 18.9% (95% CI, 18.5 to 19.4) in the cumulative frequency of infection, 37.8% (95% CI, 35.3 to 40.3) in the cumulative risk of hospitalization or death, and 40.9% (95% CI, 37.2 to 44.7) in the cumulative risk of death at two years after completion of primary vaccination. The reductions were lower by boosting every 12 months and higher by boosting every 6 months. The reductions were smaller for individuals 12-64 years of age. CONCLUSION: Boosting at a shorter interval was associated with a greater reduction in Covid-19 outcomes, especially hospitalization and death. Frequent boosting conferred greater benefits for individuals aged ≥65 than for individuals aged 12-64.

2.
Appl Microbiol Biotechnol ; 108(1): 323, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713233

RESUMEN

Ergot alkaloids (EAs) are a diverse group of indole alkaloids known for their complex structures, significant pharmacological effects, and toxicity to plants. The biosynthesis of these compounds begins with chanoclavine-I aldehyde (CC aldehyde, 2), an important intermediate produced by the enzyme EasDaf or its counterpart FgaDH from chanoclavine-I (CC, 1). However, how CC aldehyde 2 is converted to chanoclavine-I acid (CC acid, 3), first isolated from Ipomoea violacea several decades ago, is still unclear. In this study, we provide in vitro biochemical evidence showing that EasDaf not only converts CC 1 to CC aldehyde 2 but also directly transforms CC 1 into CC acid 3 through two sequential oxidations. Molecular docking and site-directed mutagenesis experiments confirmed the crucial role of two amino acids, Y166 and S153, within the active site, which suggests that Y166 acts as a general base for hydride transfer, while S153 facilitates proton transfer, thereby increasing the acidity of the reaction. KEY POINTS: • EAs possess complicated skeletons and are widely used in several clinical diseases • EasDaf belongs to the short-chain dehydrogenases/reductases (SDRs) and converted CC or CC aldehyde to CC acid • The catalytic mechanism of EasDaf for dehydrogenation was analyzed by molecular docking and site mutations.


Asunto(s)
Simulación del Acoplamiento Molecular , Mutagénesis Sitio-Dirigida , Alcaloides de Claviceps/biosíntesis , Alcaloides de Claviceps/química , Alcaloides de Claviceps/metabolismo , Aldehídos/metabolismo , Aldehídos/química , Oxidación-Reducción , Dominio Catalítico , Oxidorreductasas/metabolismo , Oxidorreductasas/genética , Oxidorreductasas/química
3.
Artículo en Inglés | MEDLINE | ID: mdl-38717675

RESUMEN

INTRODUCTION: Parkinson disease (PD) is the second most common neurodegenerative disease. Members of the Black Diaspora (MBD) and Hispanic/Latinx people are less likely to receive a timely diagnosis following the onset of symptoms and more likely to experience greater disease severity due to late diagnosis. Historically marginalized populations (i.e., MBD, Hispanic, and Latinx communities) are not accurately represented in research; this, along with many other barriers, compounds underreporting and lack of recognition of PD. It is important to understand barriers to early diagnosis and healthcare access for these historically marginalized populations from the community's perspective. METHODS: Our team conducted two focus groups to identify barriers and facilitators to PD healthcare-seeking behavior. We sought to identify which barriers are modifiable to ultimately improve engagement in neurological care for MBD and Hispanic individuals affected by PD. RESULTS: We enrolled 15 participants (13 female; African/African American/Black n = 10, Hispanic/Puerto Rican n = 3, other n = 2) for two focus groups. Discussions revealed sources of barriers to healthcare-seeking behavior in three main domains: legacy of racism in the United States, ancestral cultural environment, and healthcare system access. These sources influenced individuals' PD knowledge and familiarity. Additionally, participants expressed a desire to know more about PD and called for increased community-based programming for education and awareness. DISCUSSION: This paper uses a community-based participatory research approach to describe the experiences of MBD, Hispanic, and Latinx people in Manhattan and the surrounding areas in relation to possible sources of healthcare disparities and delayed PD diagnosis. These sources have broad implications and should be addressed through collaborative community programming.

4.
Front Microbiol ; 15: 1364486, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38699479

RESUMEN

Introduction: The composition of the intestinal microbiome correlates significantly with an animal's health status. Hence, this indicator is highly important and sensitive for protecting endangered animals. However, data regarding the fungal diversity of the wild Budorcas taxicolor (takin) gut remain scarce. Therefore, this study analyzes the fungal diversity, community structure, and pathogen composition in the feces of wild B. taxicolor. Methods: To ensure comprehensive data analyses, we collected 82 fecal samples from five geographical sites. Amplicon sequencing of the internal transcribed spacer (ITS) rRNA was used to assess fecal core microbiota and potential pathogens to determine whether the microflora composition is related to geographical location or diet. We further validated the ITS rRNA sequencing results via amplicon metagenomic sequencing and culturing of fecal fungi. Results and discussion: The fungal diversity in the feces of wild Budorcas taxicolor primarily comprised three phyla (99.69%): Ascomycota (82.19%), Fungi_unclassified (10.37%), and Basidiomycota (7.13%). At the genus level, the predominant fungi included Thelebolus (30.93%), Functional_unclassified (15.35%), and Ascomycota_unclassified (10.37%). Within these genera, certain strains exhibit pathogenic properties, such as Thelebolus, Cryptococcus, Trichosporon, Candida, Zopfiella, and Podospora. Collectively, this study offers valuable information for evaluating the health status of B. taxicolor and formulating protective strategies.

5.
Curr Res Food Sci ; 8: 100732, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38699681

RESUMEN

Camellia oil, recognized as a high-quality edible oil endorsed by the Food and Agriculture Organization, is confronted with authenticity issues arising from fraudulent adulteration practices. These practices not only pose health risks but also lead to economic losses. This study proposes a novel machine learning framework, referred to as a transformer encoder backbone with a support vector machine regressor (TES), coupled with an electronic nose (E-nose), for detecting varying adulteration levels in camellia oil. Experimental results indicate that the proposed TES model exhibits the best performance in identifying the adulterated concentration of camellia oi, compared with five other machine learning models (the support vector machine, random forest, XGBoost, K-nearest neighbors, and backpropagation neural network). The results obtained by E-nose detection are verified by complementary Fourier transform infrared (FTIR) spectroscopy analysis for identifying functional groups, ensuring accuracy and providing a comprehensive assessment of the types of adulterants. The proposed TES model combined with E-nose offers a rapid, effective, and practical tool for detecting camellia oil adulteration. This technique not only safeguards consumer health and economic interests but also promotes the application of E-nose in market supervision.

6.
Anal Chem ; 96(19): 7609-7617, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38687631

RESUMEN

MicroRNAs (miRNAs) play vital roles in biological activities, but their in vivo imaging is still challenging due to the low abundance and the lack of efficient fluorescent tools. RNA aptamers with high affinity and low background emerge for bioimaging yet suffering from low brightness. We introduce a rational design based on target-mediated entropy-driven toehold exchange (EDTE) to induce the release of RNA aptamer and subsequently light up corresponding fluorophore, which achieves selective imaging of miRNAs with good stability in both living cells and tumor-bearing mouse. Through tailoring recognition unit of the EDTE probes, highly sensitive imaging of different miRNAs including miRNA-125b and miRNA-21 is achieved, confirming its universal bioimaging applications. In comparison with the reported "one-to-one" model, the EDTE strategy shows a remarkable 4.6-time improvement in signal/noise ratio for intracellular imaging of the same miRNA. Particularly, it realizes sensitive imaging of miRNA in vivo, providing a promising tool in investigating functions and interactions of disease-associated miRNAs.


Asunto(s)
Aptámeros de Nucleótidos , Entropía , Colorantes Fluorescentes , MicroARNs , MicroARNs/análisis , MicroARNs/metabolismo , Aptámeros de Nucleótidos/química , Animales , Colorantes Fluorescentes/química , Ratones , Humanos , Imagen Óptica , Ratones Desnudos
7.
J Diabetes ; 16(5): e13564, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38664879

RESUMEN

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) and liver cirrhosis are significant clinical concerns, especially among individuals with type 2 diabetes mellitus (T2DM). However, in China, there is a paucity of reliable evidence detailing the characteristics of NAFLD and liver cirrhosis in T2DM. Furthermore, the relationship between blood glucose levels and NAFLD prevalence remains unclear. METHODS: Data from the Shanghai Suburban Adult Cohort and Biobank were analyzed, including 6621 participants with T2DM. NAFLD was diagnosed by ultrasonography and liver cirrhosis was performed according to the health information systems. Logistic regression and restricted cubic spline analysis were used to explore the potential risk factors for NAFLD and liver cirrhosis. RESULTS: The prevalence of NAFLD was 59.36%, and liver cirrhosis was 1.43% among T2DM patients. In these patients, factors like age, being female, marital status, and obesity significantly increased the risk of NAFLD. Specifically, obesity had a strong positive association with NAFLD (odds ratio [OR] = 4.70, 95% confidence interval [CI]: 4.13-5.34). The higher glycated hemoglobin (HbA1c) quartile was associated with a heightened NAFLD risk compared to the lowest quartile (all p < .001). The HbA1c-NAFLD relationship displayed a linear that mimicked an inverted L-shaped pattern. A significant positive association existed between HbA1c levels and NAFLD for HbA1c <8.00% (OR = 1.59, 95% CI: 1.44-1.75), but this was not observed for HbA1c >8.00% (OR = 1.03, 95% CI: 0.92-1.15). CONCLUSION: Systematic screening for NAFLD is essential in T2DM patients, especially with poor glucose control and obesity in female.


Asunto(s)
Diabetes Mellitus Tipo 2 , Cirrosis Hepática , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/sangre , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/sangre , Femenino , Persona de Mediana Edad , Masculino , China/epidemiología , Cirrosis Hepática/epidemiología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/sangre , Prevalencia , Factores de Riesgo , Adulto , Hemoglobina Glucada/análisis , Hemoglobina Glucada/metabolismo , Anciano , Glucemia/metabolismo , Glucemia/análisis , Obesidad/complicaciones , Obesidad/epidemiología , Pueblos del Este de Asia
8.
Phys Med Biol ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38657628

RESUMEN

Although the U-shaped architecture, represented by UNet, has become a major network model for brain tumor segmentation, the repeated convolution and sampling operations can easily lead to the loss of crucial information. Additionally, directly fusing features from different levels without distinction can easily result in feature misalignment, affecting segmentation accuracy. On the other hand, traditional convolutional blocks used for feature extraction cannot capture the abundant multi-scale information present in brain tumor images. This paper proposes a multi-scale feature-aligned segmentation model called GMAlignNet that fully utilizes Ghost convolution to solve these problems. Ghost Hierarchical Decoupled Fusion Unit and Ghost Hierarchical Decoupled Unit are used instead of standard convolutions in the encoding and decoding paths. This transformation replaces the holistic learning of volume structures by traditional convolutional blocks with multi-level learning on a specific view, facilitating the acquisition of abundant multi-scale contextual information through low-cost operations. Furthermore, a feature alignment unit is proposed that can utilize semantic information flow to guide the recovery of upsampled features. It performs pixel-level semantic information correction on misaligned features due to feature fusion. The proposed method is also employed to optimize three classic networks, namely DMFNet, HDCNet, and 3D UNet, demonstrating its effectiveness in automatic brain tumor segmentation. The proposed network model was applied to the BraTS 2018 dataset, and the results indicate that the proposed GMAlignNet achieved Dice coefficients of 81.65%, 90.07%, and 85.16% for enhancing tumor, whole tumor, and tumor core segmentation, respectively. Moreover, with only 0.29M parameters and 26.88G FLOPs, it demonstrates better potential in terms of computational efficiency and possesses the advantages of lightweight. Extensive experiments on the BraTS 2018, BraTS 2019, and BraTS 2020 datasets suggest that the proposed model exhibits better potential in handling edge details and contour recognition.

9.
J Endod ; 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38642732

RESUMEN

INTRODUCTION: This retrospective cohort study aimed to evaluate long-term healing outcomes (10-17.5 years) following contemporary endodontic microsurgery (EMS) and identify associated prognostic factors. METHODS: Clinical and radiographic data of an EMS cohort (2006-2013) from the electronic data base of Dental Hospital were reviewed retrospectively by two independent examiners to determine their survival and healing outcomes, and potential prognostic factors analyzed by Cox proportional hazards regression and logistic regression (α = 0.05). RESULTS: Through strict inclusion and exclusion criteria, and 721 EMS-treated teeth in the cohort, 309 (42.9%) were included (male, 35.0%; female, 65.0%; age, 45.83 ± 15.53 years) with mean final follow-up of 152.26 ± 26.37 months (range, 120-211; median, 148). Clinical and radiographic assessments found 80.5% of 10 years survival rate with 63.4% of success. Collectively, tooth type, tooth mobility, preoperative lesion size, clinical crown-root ratio, and crown restorations at follow-up were significantly associated with long-term success and survival over 10 years. CONCLUSIONS: The preoperative status and condition of the tooth including its alveolar bone support, and adequate full crown restorations may be relevant prognostic determinants of success and survival following EMS over time.

10.
J Transcult Nurs ; : 10436596241246976, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38634631

RESUMEN

INTRODUCTION: Due to different social and cultural backgrounds, cervical cancer patients' experience of the treatment process and quality of life after treatment will be different. This study sought to gain in-depth understanding of the experiences of Chinese cervical cancer patients as regards their quality of life and physical symptoms. METHODOLOGY: Semi-structured interviews were used to collect data. We recruited 15 women with cervical cancer in eastern China for in-depth interviews. All data were entered into the NVivo 12 software program for analysis. RESULTS: Four themes emerged from the data: (a) uncertainty; (b) physical suffering; (c) psychological pressure; and (d) challenges of marriage and family. DISCUSSION: Cervical cancer patients showed concerns about the disease itself and the physical discomfort it causes, as well as changes in social relations. Health professionals need to talk about these issues and develop strategies to address them accordingly.

11.
Clin Trials ; : 17407745241238443, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38618926

RESUMEN

BACKGROUND: The current endpoints for therapeutic trials of hospitalized COVID-19 patients capture only part of the clinical course of a patient and have limited statistical power and robustness. METHODS: We specify proportional odds models for repeated measures of clinical status, with a common odds ratio of lower severity over time. We also specify the proportional hazards model for time to each level of improvement or deterioration of clinical status, with a common hazard ratio for overall treatment benefit. We apply these methods to Adaptive COVID-19 Treatment Trials. RESULTS: For remdesivir versus placebo, the common odds ratio was 1.48 (95% confidence interval (CI) = 1.23-1.79; p < 0.001), and the common hazard ratio was 1.27 (95% CI = 1.09-1.47; p = 0.002). For baricitinib plus remdesivir versus remdesivir alone, the common odds ratio was 1.32 (95% CI = 1.10-1.57; p = 0.002), and the common hazard ratio was 1.30 (95% CI = 1.13-1.49; p < 0.001). For interferon beta-1a plus remdesivir versus remdesivir alone, the common odds ratio was 0.95 (95% CI = 0.79-1.14; p = 0.56), and the common hazard ratio was 0.98 (95% CI = 0.85-1.12; p = 0.74). CONCLUSIONS: The proposed methods comprehensively characterize the treatment effects on the entire clinical course of a hospitalized COVID-19 patient.

12.
Neurosci Bull ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619694
13.
Cancer Med ; 13(7): e7158, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38572933

RESUMEN

BACKGROUND: Thoracic adenoid cystic carcinoma (ACC) is rare, and the differences between tracheal and lung lesions have not been fully understood. METHODS: Patients were identified from a Chinese cancer center (FUSCC) (2005-2022) and the Surveillance, Epidemiology, and End Results (SEER) database (2000-2019). Incidence was calculated and trends were quantified. Clinicopathological features and overall survival (OS) were analyzed. Nomograms predicting OS were constructed. RESULTS: Totally, 55 tracheal adenoid cystic carcinoma (TACC) and 25 lung and bronchus adenoid cystic carcinoma (LACC) were included in a Chinese cohort, 121 TACC and 162 LACC included in the SEER cohort. There were larger tumor sizes, more lymph nodes and distant metastases for LACC than TACC patients. TACC patients are more likely to get local treatments. Patients with LACC had significantly worse median OS than patients with TACC (SEER cohort: 68.0 months vs. 109.0 months, p = 0.001, Chinese cohort: 62.9 months vs. 124.8 months, p = 0.061). Age, lymph node metastasis, distant metastasis and local treatment were identified as independent prognostic factors for OS of TACC. Distant metastasis and local treatment were identified for LACC. Specifically, surgery alone or in combination with radiotherapy is crucial for improving survival in both TACC and LACC. Only TACC benefits from radiotherapy alone, while chemotherapy does not improve survival for either. The nomograms constructed using these factors revealed good prognostic accuracy. CONCLUSIONS: LACC is more aggressive and has a worse prognosis than TACC. TACC patients have more opportunities for local treatment, which is important for the prognosis of both TACC and LACC. Nomograms were created for TACC and LACC to aid in personalized survival predictions and clinical decisions.


Asunto(s)
Carcinoma Adenoide Quístico , Neoplasias Pulmonares , Humanos , Carcinoma Adenoide Quístico/epidemiología , Carcinoma Adenoide Quístico/terapia , Carcinoma Adenoide Quístico/patología , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patología , Pronóstico , Nomogramas , Pulmón/patología
14.
Indian J Med Microbiol ; 49: 100574, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38561026

RESUMEN

PURPOSE: The Shewanella genus is a rare pathogen of marine origin. In recent years, there has been a continuous increase in infection cases caused by this bacterium, and we have observed the uniqueness of infections caused by this microorganism. MATERIALS AND METHODS: This study conducted a retrospective analysis of the medical history and laboratory examination data of patients infected with the Shewanella genus over the past decade. Additionally, it employed bioinformatics methods to analyze the relevant virulence factors and antibiotic resistance genes associated with the Shewanella genus. RESULTS: Over the past 10 years, we have isolated 51 cases of Shewanella, with 68.82% being Shewanella putrefaciens (35/51 cases) and 31.37% being Shewanella algae (16/51 cases). Infected individuals often had underlying diseases, with 39.22% (20/51) having malignant tumors and 25.49% (13/51) having liver and biliary system diseases primarily characterized by stones. The majority of patients, 62.74% (32/51), exhibited mixed infections, including one case with a combination of infections from three other types of bacteria and five cases with a combination of infections from two other types of bacteria. The identified microorganisms were commonly resistant to ticarcillin-clavulanic acid (23.5%), followed by cefoperazone-sulbactam (19.6%), ciprofloxacin (17.6%), and cefotaxime (17.6%). Bioinformatics analysis indicates that Shewanella can express bile hydrolysis regulators and fatty acid metabolism regulators that aid in adapting to the unique environment of the biliary tract. Additionally, it expresses abundant catalase, superoxide dismutase, and two-component signal transduction system proteins, which may be related to environmental adaptation. Shewanella also expresses various antibiotic resistance genes, including beta-lactamases and aminoglycoside modification enzymes. Iron carriers may be one of its important virulence factors. CONCLUSIONS: We speculate that the Shewanella genus may exist as a specific colonizer in the human body, and under certain conditions, it may act as a pathogen, leading to biliary infections in the host.

15.
Artículo en Inglés | MEDLINE | ID: mdl-38683555

RESUMEN

Background: This study aims to elucidate the clinical characteristics of Shewanella-related surgical site infections (SSIs) and assess the risk of mortality in patients by establishing a predictive model. Patients and Methods: A retrospective analysis of medical history and laboratory data of Shewanella-related SSI patients over the past decade was conducted via the electronic medical record (EMR) system. A predictive model for mortality risk in Shewanella-related SSI patients was established using plasma interleukin-6 (IL-6) levels combined with the Howell-PIRO scoring system. Results: Over the past 10 years, 45 strains of Shewanella were isolated from specimens such as bile, drainage fluid, and whole blood in patients with digestive tract SSIs. Among them, 21 of 45 (46.67%) patients underwent malignant tumor resection of the digestive system, 14 of 45 (31.11%) underwent endoscopic retrograde cholangiopancreatography (ERCP) common bile duct exploration or the stone removal, and seven of 45 (15.56%) were trauma repair patients with fractures and abdominal injuries. Among the 45 Shewanella-related SSI patients, 10 died within 30 days of infection, six cases involved infections with more than two other types of bacteria. The combined use of IL-6 and Howell-PIRO scores for mortality risk assessment yielded an receiver operating characteristic (ROC) curve with an area under the curve (AUC) of 0.9350, a positive predictive value of 92.71%, a negative predictive value of 94.58%, a diagnostic sensitivity of 95.35%, and a diagnostic specificity of 92.14%-all higher than the model using IL-6 or Howell-PIRO scores alone. Conclusions: We found that residents in coastal areas faced an increased risk of Shewanella-related SSI. Moreover, the higher the number of concurrent microbial infections occurring alongside Shewanella-related SSI, the greater the mortality rate among patients. The combined application of plasma IL-6 levels and the Howell-PIRO scoring system is beneficial for assessing patient mortality risk and guiding timely and proactive clinical interventions.

16.
Brief Bioinform ; 25(3)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38670157

RESUMEN

The interrelation and complementary nature of multi-omics data can provide valuable insights into the intricate molecular mechanisms underlying diseases. However, challenges such as limited sample size, high data dimensionality and differences in omics modalities pose significant obstacles to fully harnessing the potential of these data. The prior knowledge such as gene regulatory network and pathway information harbors useful gene-gene interaction and gene functional module information. To effectively integrate multi-omics data and make full use of the prior knowledge, here, we propose a Multilevel-graph neural network (GNN): a hierarchically designed deep learning algorithm that sequentially leverages multi-omics data, gene regulatory networks and pathway information to extract features and enhance accuracy in predicting survival risk. Our method achieved better accuracy compared with existing methods. Furthermore, key factors nonlinearly associated with the tumor pathogenesis are prioritized by employing two interpretation algorithms (i.e. GNN-Explainer and IGscore) for neural networks, at gene and pathway level, respectively. The top genes and pathways exhibit strong associations with disease in survival analyses, many of which such as SEC61G and CYP27B1 are previously reported in the literature.


Asunto(s)
Algoritmos , Redes Reguladoras de Genes , Neoplasias , Redes Neurales de la Computación , Humanos , Neoplasias/genética , Biología Computacional/métodos , Aprendizaje Profundo , Genómica/métodos , Multiómica
17.
Chem Biodivers ; : e202400519, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38576052

RESUMEN

One new highly degraded steroid, namely 21-nor-4-ene-chaxine A (1) furnishing a 5/6/5-tricyclic, along with one known related analogue (2), were isolated from the South China Sea sponge Spongia officinalis. Their structures including absolute configurations were established by extensive spectroscopic data analysis, TDDFT-ECD calculation, and comparison with the spectral data previously reported in the literature. Compound 1 represent the new member of incisterols family with a highly degradation in ring B. In vitro bioassays revealed compound 2 exhibited significant anti-microglial inflammatory effect on lipopolysaccharide (LPS)-induced inflammation in BV-2 microglial cells.

18.
Int J Mol Sci ; 25(8)2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38674099

RESUMEN

In agriculture, soil-borne fungal pathogens, especially Fusarium oxysporum strains, are posing a serious threat to efforts to achieve global food security. In the search for safer agrochemicals, silica nanoparticles (SiO2NPs) have recently been proposed as a new tool to alleviate pathogen damage including Fusarium wilt. Hollow mesoporous silica nanoparticles (HMSNs), a unique class of SiO2NPs, have been widely accepted as desirable carriers for pesticides. However, their roles in enhancing disease resistance in plants and the specific mechanism remain unknown. In this study, three sizes of HMSNs (19, 96, and 406 nm as HMSNs-19, HMSNs-96, and HMSNs-406, respectively) were synthesized and characterized to determine their effects on seed germination, seedling growth, and Fusarium oxysporum f. sp. phaseoli (FOP) suppression. The three HMSNs exhibited no side effects on cowpea seed germination and seedling growth at concentrations ranging from 100 to 1500 mg/L. The inhibitory effects of the three HMSNs on FOP mycelial growth were very weak, showing inhibition ratios of less than 20% even at 2000 mg/L. Foliar application of HMSNs, however, was demonstrated to reduce the FOP severity in cowpea roots in a size- and concentration-dependent manner. The three HMSNs at a low concentration of 100 mg/L, as well as HMSNs-19 at a high concentration of 1000 mg/L, were observed to have little effect on alleviating the disease incidence. HMSNs-406 were most effective at a concentration of 1000 mg/L, showing an up to 40.00% decline in the disease severity with significant growth-promoting effects on cowpea plants. Moreover, foliar application of HMSNs-406 (1000 mg/L) increased the salicylic acid (SA) content in cowpea roots by 4.3-fold, as well as the expression levels of SA marker genes of PR-1 (by 1.97-fold) and PR-5 (by 9.38-fold), and its receptor gene of NPR-1 (by 1.62-fold), as compared with the FOP infected control plants. Meanwhile, another resistance-related gene of PAL was also upregulated by 8.54-fold. Three defense-responsive enzymes of POD, PAL, and PPO were also involved in the HMSNs-enhanced disease resistance in cowpea roots, with varying degrees of reduction in activity. These results provide substantial evidence that HMSNs exert their Fusarium wilt suppression in cowpea plants by activating SA-dependent SAR (systemic acquired resistance) responses rather than directly suppressing FOP growth. Overall, for the first time, our results indicate a new role of HMSNs as a potent resistance inducer to serve as a low-cost, highly efficient, safe and sustainable alternative for plant disease protection.


Asunto(s)
Resistencia a la Enfermedad , Fusarium , Germinación , Nanopartículas , Enfermedades de las Plantas , Plantones , Dióxido de Silicio , Fusarium/efectos de los fármacos , Dióxido de Silicio/química , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Nanopartículas/química , Germinación/efectos de los fármacos , Resistencia a la Enfermedad/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/efectos de los fármacos , Plantones/microbiología , Vigna/microbiología , Vigna/crecimiento & desarrollo , Vigna/efectos de los fármacos , Porosidad
19.
Artículo en Inglés | MEDLINE | ID: mdl-38603469

RESUMEN

The electrochemical interface formed between an electrode and an electrolyte significantly affects the rate and mechanism of the electrode reaction through its structure and properties, which vary across the interface. The scope of the interface has been expanded, along with the development of energy electrochemistry, where a solid-electrolyte interphase may form on the electrode and the active materials change properties near the surface region. Developing a comprehensive understanding of electrochemical interfaces and interphases necessitates three-dimensional spatial resolution characterization. Atomic force microscopy (AFM) offers advantages of imaging and long-range force measurements. Here we assess the capabilities of AFM by comparing the force curves of different regimes and various imaging modes for in situ characterizing of electrochemical interfaces and interphases. Selected examples of progress on work related to the structures and processes of electrode surfaces, electrical double layers, and lithium battery systems are subsequently illustrated. Finally, this review provides perspectives on the future development of electrochemical AFM.

20.
J Am Chem Soc ; 146(14): 9721-9727, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38556809

RESUMEN

The volumetric density of the metal atomic site is decisive to the operating efficiency of the photosynthetic nanoreactor, yet its rational design and synthesis remain a grand challenge. Herein, we report a shell-regulating approach to enhance the volumetric density of Co atomic sites onto/into multishell ZnxCd1-xS for greatly improving CO2 photoreduction activity. We first establish a quantitative relation between the number of shell layers, specific surface areas, and volumetric density of atomic sites on multishell ZnxCd1-xS and conclude a positive relation between photosynthetic performance and the number of shell layers. The triple-shell ZnxCd1-xS-Co1 achieves the highest CO yield rate of 7629.7 µmol g-1 h-1, superior to those of the double-shell ZnxCd1-xS-Co1 (5882.2 µmol g-1 h-1) and single-shell ZnxCd1-xS-Co1 (4724.2 µmol g-1 h-1). Density functional theory calculations suggest that high-density Co atomic sites can promote the mobility of photogenerated electrons and enhance the adsorption of Co(bpy)32+ to increase CO2 activation (CO2 → CO2* → COOH* → CO* → CO) via the S-Co-bpy interaction, thereby enhancing the efficiency of photocatalytic CO2 reduction.

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