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1.
J Nat Prod ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949068

RESUMEN

Ten undocumented carbazole derivatives (2-11) along with the reported analogue (1) were isolated from the mangrove-derived Streptomyces sp. OUCMDZ-5511, cultured with NaBr-supplemented liquid medium. Compounds 1-7 are brominated carbazoles, and 8, 10, and 11 feature an additional thiazole or 2,3-dihydro-1,4-oxathiine rings, respectively. Their structures were identified through spectroscopic techniques, computational chemistry, and X-ray crystallography. Notably, compounds 6 and 8 effectively inhibited immune cell migration, indicating anti-inflammatory activity in vivo, potentially via Myd88/Nf-κB pathways, as suggested for compound 6.

2.
J Chem Inf Model ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949724

RESUMEN

Ameliorating microglia-mediated neuroinflammation is a crucial strategy in developing new drugs for neurodegenerative diseases. Plant compounds are an important screening target for the discovery of drugs for the treatment of neurodegenerative diseases. However, due to the spatial complexity of phytochemicals, it becomes particularly important to evaluate the effectiveness of compounds while avoiding the mixing of cytotoxic substances in the early stages of compound screening. Traditional high-throughput screening methods suffer from high cost and low efficiency. A computational model based on machine learning provides a novel avenue for cytotoxicity determination. In this study, a microglia cytotoxicity classifier was developed using a machine learning approach. First, we proposed a data splitting strategy based on the molecule murcko generic scaffold, under this condition, three machine learning approaches were coupled with three kinds of molecular representation methods to construct microglia cytotoxicity classifier, which were then compared and assessed by the predictive accuracy, balanced accuracy, F1-score, and Matthews Correlation Coefficient. Then, the recursive feature elimination integrated with support vector machine (RFE-SVC) dimension reduction method was introduced to molecular fingerprints with high dimensions to further improve the model performance. Among all the microglial cytotoxicity classifiers, the SVM coupled with ECFP4 fingerprint after feature selection (ECFP4-RFE-SVM) obtained the most accurate classification for the test set (ACC of 0.99, BA of 0.99, F1-score of 0.99, MCC of 0.97). Finally, the Shapley additive explanations (SHAP) method was used in interpreting the microglia cytotoxicity classifier and key substructure smart identified as structural alerts. Experimental results show that ECFP4-RFE-SVM have reliable classification capability for microglia cytotoxicity, and SHAP can not only provide a rational explanation for microglia cytotoxicity predictions, but also offer a guideline for subsequent molecular cytotoxicity modifications.

4.
Front Neurol ; 15: 1373306, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952470

RESUMEN

Background: Cerebral small vessel disease (CSVD) is a common neurodegenerative condition in the elderly, closely associated with cognitive impairment. Early identification of individuals with CSVD who are at a higher risk of developing cognitive impairment is crucial for timely intervention and improving patient outcomes. Objective: The aim of this study is to construct a predictive model utilizing LASSO regression and binary logistic regression, with the objective of precisely forecasting the risk of cognitive impairment in patients with CSVD. Methods: The study utilized LASSO regression for feature selection and logistic regression for model construction in a cohort of CSVD patients. The model's validity was assessed through calibration curves and decision curve analysis (DCA). Results: A nomogram was developed to predict cognitive impairment, incorporating hypertension, CSVD burden, apolipoprotein A1 (ApoA1) levels, and age. The model exhibited high accuracy with AUC values of 0.866 and 0.852 for the training and validation sets, respectively. Calibration curves confirmed the model's reliability, and DCA highlighted its clinical utility. The model's sensitivity and specificity were 75.3 and 79.7% for the training set, and 76.9 and 74.0% for the validation set. Conclusion: This study successfully demonstrates the application of machine learning in developing a reliable predictive model for cognitive impairment in CSVD. The model's high accuracy and robust predictive capability provide a crucial tool for the early detection and intervention of cognitive impairment in patients with CSVD, potentially improving outcomes for this specific condition.

5.
Front Pharmacol ; 15: 1371811, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38957384

RESUMEN

Objective: The study was designed to develop and validate a new drug clinical trial participation feelings questionnaire (DCTPFQ) for cancer patients. Methods: Data collection and analysis involved a combination of qualitative and quantitative methods. There were two phases to this study. Phase Ⅰ involved developing a questionnaire to establish a list of items to be included in the pool: A theoretical framework was constructed based on the transitions theory and the Roper-Logan-Tierney theory. After incorporating a theoretical framework, interviewing participants, and reviewing the literature, 44 items were generated. After a Delphi consultation and a pilot test, 36 items proceeded to item analysis and exploratory factor analysis (EFA), and a four-factor structure with 21 items was formed. Confirmatory factor analysis (CFA), test-retest reliability, criteria-related validity, and internal consistency tests were conducted in phase II to examine the psychometric properties. Results: There were 21 items on the DCTPFQ, ranging from 1 (fully disagree) through 5 (fully agree). As a result of EFA and CFA, the four factors of DCTPFQ could be verified, including cognitive engagement, subjective experience, medical resources, and relatives and friends' support. Test-retest reliability of the DCTPFQ was 0.840, and Cronbach's alpha was 0.934. DCTPFQ is significantly correlated with the Fear of Progression Questionnaire-short form (r = 0.731, p < 0.05) and the Mishel's Uncertainty in Illness Scale (r = 0.714, p < 0.05). Conclusion: The DCTPFQ is a useful tool for measuring the drug clinical trial participation feelings among cancer patients.

6.
Mol Nutr Food Res ; : e2400010, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958100

RESUMEN

SCOPE: Celiac disease (CD) is an allergic intestinal disease caused mainly by gliadin in wheat, which is widespread in the population and currently lacks effective treatment. α-Gliadin peptides cause cellular damage by substantially increasing cellular reactive oxygen species (ROS) levels. METHODS AND RESULTS: This study investigates the protective effect of 11 pea-derived peptides (PPs) on ɑ-gliadin peptide (P31-43) treated Caco-2 cells. Results show that cells treated with PP2, PP5, and PP6 peptides significantly reduce the cell mortality caused by P31-43. Three PPs significantly reduce the P31-43-induced decrease in ROS levels to control levels, and there is no difference between them and the vitamin C (Vc) group. The results in terms of antioxidant-related enzymes show that PPs significantly decrease superoxide dismutase activity (SOD), glutathione reductases (GR), and glutathione (GSH)/oxidized glutathione (GSSG) levels, thus significantly enhancing the antioxidant level of cells. By studying the key proteins of the Kelch-like ECH-associated protein 1 (Keap1)/NF-E2-related factor 2 (Nrf2) pathway, it is found that PPs activate the Keap1/Nrf2 signaling pathway. CONCLUSION: The study finds that peptides from peas can effectively alleviate ɑ-gliadin peptide-induced cell damage. The discovery of these food-derived peptides provides novel potential solutions for the prevention and treatment of CD.

7.
ACS Appl Mater Interfaces ; 16(26): 33396-33403, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38961570

RESUMEN

Germanium has been recognized as a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity and excellent lithium-ion diffusivity. Nonetheless, it is challenging to enhance both the high-rate performance and long-term cycling stability simultaneously. This study introduces a novel heterostructure composed of germanium nanosheets integrated with graphene (Ge NSs@Gr). These nanosheets undergo an in situ phase transformation from a hydrogen-terminated multilayer germanium compound termed germanane (GeH) derived via topochemical deintercalation from CaGe2. This approach mitigates oxidation and prevents restacking by functionalizing the exfoliated germanane with octadecenoic organic molecules. The resultant germanium nanosheets retain their structural integrity from CaGe2 and present an exposed, active (111) surface that features an open crystal lattice, facilitating swift lithium-ion migration conducive to lithium storage. The composite material delivers a substantial reversible capacity of 1220 mA h g-1 at a current density of 0.2 C and maintains a capacity of 456 mA h g-1 even at an ultrahigh current density of 10 C over extended cycling. Impressively, a capacity of 316 mA h g-1 remains after 5000 cycles. The exceptional high-rate performance and durable cycling stability underscore the Ge NSs@Gr anode's potential as a highly viable option for LIBs.

8.
Sci Total Environ ; 946: 174368, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38955273

RESUMEN

The possible contamination routes, environmental adaptation, and genetic basis of Cronobacter spp. in infant and follow-up formula production factories and retailed products in mainland China have been determined by laboratory studies and whole-genome comparative analysis in a 7-year nationwide continuous surveillance spanning from 2012 to 2018. The 2-year continuous multicenter surveillance of the production process (conducted in 2013 and 2014) revealed that the source of Cronobacter spp. in the dry-blending process was the raw dry ingredients and manufacturing environment (particularly in the vibro sieve and vacuum cleaner), while in the combined process, the main contamination source was identified as the packing room. It is important to note that, according to the contamination control knowledge obtained from the production process surveillance, the contamination rate of retail powdered infant formula (PIF) and follow-up formula (FUF) products in China decreased significantly from 2016 onward, after improving the hygiene management practices in factories. The prevalence of Cronobacter spp. in retailed PIF and FUF in China in 2018 was dramatically reduced from 1.55 % (61/3925, in 2012) to an average as low as 0.17 % (13/7655 in 2018). Phenotype determination and genomic analysis were performed on a total of 90 Cronobacter spp. isolates obtained from the surveillance. Of the 90 isolates, only two showed resistance to either cefazolin or cefoxitin. The multilocus sequence typing results revealed that C. sakazakii sequence type 1 (ST1), ST37, and C. malonaticus ST7 were the dominant sequence types (STs) collected from the production factories, while C. sakazakii ST1, ST4, ST64, and ST8 were the main STs detected in the retailed PIF and FUF nationwide. One C. sakazakii ST4 isolate (1.1 %, 1/90) had strong biofilm-forming ability and 13 isolates (14.4 %, 13/90) had weak biofilm-forming ability. Genomic analysis revealed that Cronobacter spp. have a relatively stable core-genome and an increasing pan-genome size. Plasmid IncFIB (pCTU3) was prevalent in this genus and some contained 14 antibacterial biocide- and metal-resistance genes (BMRGs) including copper, silver, and arsenic resistant genes. Plasmid IncN_1 was predicted to contain 6 ARGs. This is the first time that a multi-drug resistance IncN_1 type plasmid has been reported in Cronobacter spp. Genomic variations with respect to BMRGs, virulence genes, antimicrobial resistance genes (ARGs), and genes involved in biofilm formation were observed among strains of this genus. There were apparent differences in copies of bcsG and flgJ between the biofilm-forming group and non-biofilm-forming group, indicating that these two genes play key roles in biofilm formation. The findings of this study have improved our understanding of the contamination characteristics and genetic basis of Cronobacter spp. in PIF and FUF and their production environment in China and provide important guidance to reduce contamination with this pathogen during the production of PIF and FUF.

10.
Sci Rep ; 14(1): 15150, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956232

RESUMEN

Adjuvant oxaliplatin plus S-1 (SOX) chemotherapy for gastric cancer (GC) after D2 gastrectomy has been proven effective. There has yet to be a study that evaluates adjuvant nanoparticle albumin-bound paclitaxel (nab-paclitaxel) plus S-1. In this single-center, retrospective study, GC patients after D2 gastrectomy received either nab-paclitaxel plus S-1 (AS group) or SOX group were recruited between January 2018 and December 2020 in The First Affiliated Hospital of Zhejiang University. Intravenous nab-paclitaxel 120 mg/m2 or 260 mg/m2 and oxaliplatin 130 mg/m2 were administered as eight 3 week cycle, especially in the AS and SOX group. Patients received S-1 twice daily with a dose of 40 mg/m2 in the two groups on days 1-14 of each cycle. The end points were disease-free survival (DFS) rate at 3 years and adverse events (AEs). There were 56 eligible patients, 28 in the AS group and 35 in the SOX group. The 3 year DFS rate was 78.0% in AS group versus 70.7% in SOX group (p = 0.46). Subgroup analysis showed that the patients with signet-ring positive in the AS group had a prolonged DFS compared with the SOX group (40.0 vs. 13.8 m, p = 0.02). The diffuse-type GC or low differentiation in the AS group was associated with numerically prolonged DFS compared with the SOX group, but the association was not statistically significant (p = 0.27 and p = 0.15 especially). Leukopenia (14.3%) were the most prevalent AEs in the AS group, while thrombocytopenia (28.5%) in the SOX group. Neutropenia (7.1% in AS group) and thrombocytopenia (22.8% in SOX group) were the most common grade 3 or 4 AEs. In this study analyzing past data, a tendency towards a greater 3 year DFS was observed when using AS regimen in signet-ring positive patients. AS group had fewer thrombocytopenia compared to SOX group. More studies should be conducted with larger sample sizes.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Combinación de Medicamentos , Gastrectomía , Oxaliplatino , Ácido Oxónico , Neoplasias Gástricas , Tegafur , Humanos , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Neoplasias Gástricas/mortalidad , Masculino , Femenino , Tegafur/administración & dosificación , Tegafur/efectos adversos , Tegafur/uso terapéutico , Persona de Mediana Edad , Oxaliplatino/administración & dosificación , Oxaliplatino/uso terapéutico , Estudios Retrospectivos , Gastrectomía/métodos , Ácido Oxónico/administración & dosificación , Ácido Oxónico/efectos adversos , Ácido Oxónico/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Anciano , Quimioterapia Adyuvante/métodos , Paclitaxel Unido a Albúmina/administración & dosificación , Paclitaxel Unido a Albúmina/uso terapéutico , Adulto , Supervivencia sin Enfermedad , Paclitaxel/administración & dosificación , Paclitaxel/uso terapéutico , Paclitaxel/efectos adversos , Albúminas/administración & dosificación
11.
medRxiv ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38947082

RESUMEN

Elevated anxiety and uncertainty avoidance are known to exacerbate maladaptive choice in individuals with affective disorders. However, the differential roles of state vs. trait anxiety remain unclear, and underlying computational mechanisms have not been thoroughly characterized. In the present study, we investigated how a somatic (interoceptive) state anxiety induction influences learning and decision-making under uncertainty in individuals with clinically significant levels of trait anxiety. A sample of 58 healthy comparisons (HCs) and 61 individuals with affective disorders (iADs; i.e., depression and/or anxiety) completed a previously validated explore-exploit decision task, with and without an added breathing resistance manipulation designed to induce state anxiety. Computational modeling revealed a pattern in which iADs showed greater information-seeking (i.e., directed exploration; Cohen's d=.39, p=.039) in resting conditions, but that this was reduced by the anxiety induction. The affective disorders group also showed slower learning rates across conditions (Cohen's d=.52, p=.003), suggesting more persistent uncertainty. These findings highlight a complex interplay between trait anxiety and state anxiety. Specifically, while elevated trait anxiety is associated with persistent uncertainty, acute somatic anxiety can paradoxically curtail exploratory behaviors, potentially reinforcing maladaptive decision-making patterns in affective disorders.

12.
Sci Rep ; 14(1): 15519, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969693

RESUMEN

The selection of implants for fixing unstable femoral neck fractures (FNF) remains contentious. This study employs finite element analysis to examine the biomechanics of treating Pauwels type III femoral neck fractures using cannulated compression screws (3CS), biplane double-supported screw fixation (BDSF), and the femoral neck system (FNS). A three-dimensional model of the proximal femur was developed using computed tomography scans. Fracture models of the femoral neck were created with 3CS, BDSF, and FNS fixations. Von Mises stress on the proximal femur, fracture ends, internal fixators, and model displacements were assessed and compared across the three fixation methods (3CS, BDSF, and FNS) during the heel strike of normal walking. The maximum Von Mises stress in the proximal fragment was significantly higher with 3CS fixation compared to BDSF and FNS fixations (120.45 MPa vs. 82.44 MPa and 84.54 MPa, respectively). Regarding Von Mises stress distribution at the fracture ends, the highest stress in the 3CS group was 57.32 MPa, while BDSF and FNS groups showed 51.39 MPa and 49.23 MPa, respectively. Concerning implant stress, the FNS model exhibited greater Von Mises stress compared to the 3CS and BDSF models (236.67 MPa vs. 134.86 MPa and 140.69 MPa, respectively). Moreover, BDSF displayed slightly lower total displacement than 3CS fixation (7.19 mm vs. 7.66 mm), but slightly higher displacement than FNS (7.19 mm vs. 7.03 mm). This study concludes that BDSF outperforms 3CS fixation in terms of biomechanical efficacy and demonstrates similar performance to the FNS approach. As a result, BDSF stands as a dependable alternative for treating Pauwels type III femoral neck fractures.


Asunto(s)
Tornillos Óseos , Fracturas del Cuello Femoral , Análisis de Elementos Finitos , Fijación Interna de Fracturas , Fracturas del Cuello Femoral/cirugía , Fracturas del Cuello Femoral/fisiopatología , Fijación Interna de Fracturas/métodos , Humanos , Fenómenos Biomecánicos , Estrés Mecánico , Tomografía Computarizada por Rayos X
13.
BMC Cancer ; 24(1): 800, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965506

RESUMEN

Drug resistance remains a significant challenge in the treatment of pancreatic cancer. The development of drug-resistant cell lines is crucial to understanding the underlying mechanisms of resistance and developing novel drugs to improve clinical outcomes. Here, a novel pancreatic cancer cell line, PDAC-X1, derived from Chinese patients has been established. PDAC-X1 was characterized by the immune phenotype, biology, genetics, molecular characteristics, and tumorigenicity. In vitro analysis revealed that PDAC-X1 cells exhibited epithelial morphology and cell markers (CK7 and CK19), expressed cancer-associated markers (E-cadherin, Vimentin, Ki-67, CEA, CA19-9), and produced pancreatic cancer-like organs in suspension culture. In vivo analysis showed that PDAC-X1 cells maintained tumorigenicity with a 100% tumor formation rate. This cell line exhibited a complex karyotype, dominated by subtriploid karyotypes. In addition, PDAC-X1 cells exhibited intrinsic multidrug resistance to multiple drugs, including gemcitabine, paclitaxel, 5-fluorouracil, and oxaliplatin. In conclusion, the PDAC-X1 cell line has been established and characterized, representing a useful and valuable preclinical model to study the underlying mechanisms of drug resistance and develop novel drug therapeutics to improve patient outcomes.


Asunto(s)
Carcinoma Ductal Pancreático , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Neoplasias Pancreáticas , Humanos , Línea Celular Tumoral , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Animales , Ratones , Resistencia a Múltiples Medicamentos/genética , Ensayos Antitumor por Modelo de Xenoinjerto , Masculino , Femenino , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Gemcitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Desoxicitidina/uso terapéutico
14.
J Colloid Interface Sci ; 675: 251-262, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38970911

RESUMEN

Li-rich Mn-based (LMR) layered oxides are considered promising cathode materials for high energy-density Li-ion batteries. Nevertheless, challenges such as irreversible oxygen loss at the surface during the initial charge, alteration of the bulk structure, and poor rate performance impede their path to commercialisation. Most modification methods focus on specific layers, making the overall impact of modifications at various depths on the properties of materials unclear. This research presents an approach by using doping to adjust both surface and bulk properties; the materials with surface and bulk fluoride anion doping are synthesised to explore the connection between doping depth, structural and electrochemical stability. The surface-doped material significantly improves the initial Coulombic efficiency (ICE) from 77.85% to 85.12% and limits phase transitions, yet it does not enhance rate performance. Conversely, doping in bulk stands out by improving both rate performance and cyclic stability: it increases the specific discharge capacity by around 60 mAh g-1 and enhances capacity retention from 57.69% to 82.26% after 300 cycles at 5C. These results highlight a notable dependence of material properties on depth, providing essential insights into the mechanisms of surface and bulk modifications.

15.
J Cardiothorac Surg ; 19(1): 411, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956670

RESUMEN

BACKGROUND: Tricuspid regurgitation (TR) is a common valvular heart disease worldwide, and current guidelines for TR treatment are relatively conservative, as well as with detrimental outcomes. Restoration of sinus rhythm was reported to improve the TR severity in those TR patients with atrial fibrillation (AF). However, relevant research was limited. The aim of this meta-analysis was to evaluate the clinical outcomes of restoration of sinus rhythm in TR patients with AF. METHODS: In this study, PubMed, Web of Science, and Scopus databases were searched for study enrollment until July 2023. This study was designed under the guidance of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. These studies containing the patient's baseline characteristics, surgical procedure, and at least one of the clinical outcomes were included. The primary endpoint was TR grade during follow-up after restoration of sinus rhythm. RESULTS: Out of 1074 records, 6 were enrolled. Restoration of sinus rhythm is associated with a reduction of TR severity (TR grade, odds ratio 0.11, 95% confidence interval (CI): 0.01 to 1.28, P = 0.08, I2 = 83%; TR area, mean difference (MD) -2.19 cm2, 95% CI: -4.17 to -0.21 cm2, P = 0.03, I2 = 96%). Additionally, remolding of right heart with a significant reduction of tricuspid valve annulus diameter (MD -0.36 cm, 95%CI: -0.47 to -0.26 cm, P < 0.00001, I2 = 29%) and right atrium volume index (MD -11.10 mL/m2, 95%CI: -16.81 to -5.39 mL/m2, P = 0.0001, I2 = 79%) was observed during follow-up. CONCLUSIONS: In conclusion, rhythm-control therapy could reduce TR severity in AF patients with TR and is associated with right heart remodeling.


Asunto(s)
Fibrilación Atrial , Insuficiencia de la Válvula Tricúspide , Fibrilación Atrial/cirugía , Fibrilación Atrial/fisiopatología , Humanos , Insuficiencia de la Válvula Tricúspide/cirugía , Insuficiencia de la Válvula Tricúspide/fisiopatología , Frecuencia Cardíaca/fisiología
16.
Inorg Chem ; 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973094

RESUMEN

Metal nanozymes have offered attractive opportunities for biocatalysis and biomedicine. However, fabricating nanozymes simultaneously possessing highly catalytic selectivity and activity remains a great challenge due to the lack of three-dimensional (3D) architecture of the catalytic pocket in natural enzymes. Here, we integrate rhodium nanocluster (RhNC), reduced graphene oxide (rGO), and protamine (PRTM, a typical arginine-rich peptide) into a composite facilely based on the single peptide. Remarkably, the PRTM-RhNC@rGO composite displays outstanding selectivity, activity, and stability for the catalytic degradation of uric acid. The reaction rate constant of the uric acid oxidation catalyzed by the PRTM-RhNC@rGO composite is about 1.88 × 10-3 s-1 (4 µg/mL), which is 37.6 times higher than that of reported RhNP (k = 5 × 10-5 s-1, 20 µg/mL). Enzyme kinetic studies reveal that the PRTM-RhNC@rGO composite exhibits a similar affinity for uric acid as natural uricase. Furthermore, the uricase-like activity of PRTM-RhNC@rGO nanozymes remains in the presence of sulfur substances and halide ions, displaying incredibly well antipoisoning abilities. The analysis of the structure-function relationship indicates the PRTM-RhNC@rGO composite features the substrate binding site near the catalytic site in a confined space contributed by 2D rGO and PRTM, resulting in the high-performance of the composite nanozyme. Based on the outstanding uricase-like activity and the interaction of PRTM and uric acid, the PRTM-RhNC@rGO composite can retard the urate crystallization significantly. The present work provides new insights into the design of metal nanozymes with suitable binding sites near catalytic sites by mimicking pocket-like structures in natural enzymes based on simple peptides, conducing to broadening the practical application of high-performance nanozymes in biomedical fields.

17.
Phytother Res ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38973314

RESUMEN

Tamarixetin, a natural dietary flavone, exhibits remarkable potential for the treatment of ischemic stroke. The present article aimed to explore the impact of tamarixetin on ischemic stroke and elucidate the underlying mechanisms. Effects of tamarixetin on ischemic stroke were evaluated in rats using the middle cerebral artery occlusion and reperfusion (MCAO/R) model, by assessing the neurological deficit scores, brain water content, brain infraction, and neuronal damage. The levels of proinflammatory cytokines, NLRP3 inflammasome activation, reactive oxygen species (ROS) production, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression were measured in MCAO/R rats and lipopolysaccharide-stimulated cells. Tamarixetin administration improved the neurological dysfunction and neuronal loss in MCAO/R rats. In addition, tamarixetin reduced microglial hyperactivation and proinflammatory cytokines expression in vivo and in vitro. Tamarixetin attenuated NF-κB p65 phosphorylation and promoter activity, reduced NLRP3 expression and caspase-1 cleavage, and downregulated IL-1ß and IL-18 secretions to suppress NLRP3 inflammasome activation. The levels of superoxide anion, hydrogen peroxide, and ROS were also suppressed by tamarixetin. The downregulation of NADP+ and NADPH levels, and gp91phox expression indicated the ameliorative effects of tamarixetin on NADPH oxidase activation. In the gp91phox knockdown cells treated with lipopolysaccharide, the effects of tamarixetin on NADPH oxidase activation, ROS generation, and NLRP3 inflammasome activation were diminished. Moreover, tamarixetin protects neurons against microglial hyperactivation in vitro. Our findings support the potential of tamarixetin as a therapeutic agent for ischemic stroke, and its mechanism of action involves the inhibition of NADPH oxidase-NLRP3 inflammasome signaling.

18.
Diabetes Metab Syndr Obes ; 17: 2619-2625, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974951

RESUMEN

Purpose: To examine the risk of type 2 diabetes mellitus in non-obese patients with pancreatic fatty infiltration through abdominal computed tomography (CT) quantitation. Patients and Methods: We carried out a retrospective analysis of abdominal CT and inpatient medical records of 238 inpatients from July 2019 to April 2021. The patients were divided into a normal non-obese group (BMI < 25, n = 135) and diabetic non-obese group (BMI < 25, n = 103). Abdominal CT-related parameters included body width; mean CT values of the pancreas, liver, and spleen; difference between pancreas and spleen CT values (P-S); pancreas-to-spleen attenuation ratio (P/S); and liver-to-spleen attenuation ratio (L/S). Logistic regression was used to estimate the risk factors for comorbid diabetes in a non-obese population. Results: The P-values of the pancreas CT value, P-S, P/S, body width, and L/S were all <0.05 and correlated to comorbid diabetes in non-obese patients. Worsening pancreatic fatty infiltration increased the risk of developing diabetes. Using a P/S of 1.0 as reference, every successive decrease in this ratio by 0.1 increases patient risk by 3.981, 4.452, 6.037, and 12.937 times. Conclusion: The risk of developing type 2 diabetes mellitus in non-obese patients increases with the degree of pancreatic fatty infiltration as assessed by CT.

19.
World J Stem Cells ; 16(6): 728-738, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38948093

RESUMEN

BACKGROUND: Necrotizing enterocolitis (NEC) is a severe gastrointestinal disease that affects premature infants. Although mounting evidence supports the therapeutic effect of exosomes on NEC, the underlying mechanisms remain unclear. AIM: To investigate the mechanisms underlying the regulation of inflammatory response and intestinal barrier function by umbilical cord mesenchymal stem cell (UCMSCs) exosomes, as well as their potential in alleviating NEC in neonatal mice. METHODS: NEC was induced in 5-d-old C57BL/6 pups through hypoxia and gavage feeding of formula containing lipopolysaccharide (LPS), after which the mice received human UCMSC exosomes (hUCMSC-exos). The control mice were allowed to breastfeed with their dams. Ileal tissues were collected from the mice and analyzed by histopathology and immunoblotting. Colon tissues were collected from NEC neonates and analyzed by immunofluorescence. Molecular biology and cell culture approaches were employed to study the related mechanisms in intestinal epithelial cells. RESULTS: We found that autophagy is overactivated in intestinal epithelial cells during NEC, resulting in reduced expression of tight junction proteins and an increased inflammatory response. The ability of hUCMSC-exos to ameliorate NEC in a mouse model was dependent on decreased intestinal autophagy. We also showed that hUCMSC-exos alleviate the inflammatory response and increase migration ability in intestinal epithelial cells induced by LPS. CONCLUSION: These results contribute to a better understanding of the protective mechanisms of hUCMSC-exos against NEC and provide a new theoretical and experimental foundation for NEC treatment. These findings also enhance our understanding of the role of the autophagy mechanism in NEC, offering potential avenues for identifying new therapeutic targets.

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