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1.
Nano Lett ; 24(17): 5206-5213, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647212

RESUMO

Single Atoms Catalysts (SACs) have emerged as a class of highly promising heterogeneous catalysts, where the traditional bottom-up synthesis approaches often encounter considerable challenges in relation to aggregation issues and poor stability. Consequently, achieving densely dispersed atomic species in a reliable and efficient manner remains a key focus in the field. Herein, we report a new facile electrochemical knock-down strategy for the formation of SACs, whereby the metal Zn clusters are transformed into single atoms. While a defect-rich substrate plays a pivotal role in capturing and stabilizing isolated Zn atoms, the feasibility of this novel strategy is demonstrated through a comprehensive investigation, combining experimental and theoretical studies. Furthermore, when studied in exploring for potential applications, the material prepared shows a remarkable improvement of 58.21% for the Li+ storage and delivers a capacity over 300 Wh kg-1 after 500 cycles upon the transformation of Zn clusters into single atoms.

2.
Nat Commun ; 15(1): 2970, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582759

RESUMO

Photoelectrochemical seawater splitting is a promising route for direct utilization of solar energy and abundant seawater resources for H2 production. However, the complex salinity composition in seawater results in intractable challenges for photoelectrodes. This paper describes the fabrication of a bilayer stack consisting of stainless steel and TiO2 as a cocatalyst and protective layer for Si photoanode. The chromium-incorporated NiFe (oxy)hydroxide converted from stainless steel film serves as a protective cocatalyst for efficient oxygen evolution and retarding the adsorption of corrosive ions from seawater, while the TiO2 is capable of avoiding the plasma damage of the surface layer of Si photoanode during the sputtering of stainless steel catalysts. By implementing this approach, the TiO2 layer effectively shields the vulnerable semiconductor photoelectrode from the harsh plasma sputtering conditions in stainless steel coating, preventing surface damages. Finally, the Si photoanode with the bilayer stack inhibits the adsorption of chloride and realizes 167 h stability in chloride-containing alkaline electrolytes. Furthermore, this photoanode also demonstrates stable performance under alkaline natural seawater for over 50 h with an applied bias photon-to-current efficiency of 2.62%.

3.
JAMA Cardiol ; 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38583091

RESUMO

Importance: High-dose trivalent compared with standard-dose quadrivalent influenza vaccine did not significantly reduce all-cause mortality or cardiopulmonary hospitalizations in patients with high-risk cardiovascular disease in the INVESTED trial. Whether humoral immune response to influenza vaccine is associated with clinical outcomes is unknown. Objective: To examine the antibody response to high-dose trivalent compared with standard-dose quadrivalent inactivated influenza vaccine and its associations with clinical outcomes. Design, Setting, and Participants: This secondary analysis is a prespecified analysis of the immune response substudy of the randomized, double-blind, active-controlled INVESTED trial, which was conducted at 157 sites in the United States and Canada over 3 influenza seasons between September 2016 and January 2019. Antibody titers were determined by hemagglutination inhibition assays at randomization and 4 weeks during the 2017-2018 and 2018-2019 seasons. Eligibility criteria included recent acute myocardial infarction or heart failure hospitalization and at least 1 additional risk factor. Data were analyzed from February 2023 to June 2023. Main Outcomes and Measures: Mean antibody titer change, seroprotection (antibody titer level ≥1:40) and seroconversion (≥4-fold increase in titer) at 4 weeks, and the association between seroconversion status and the risk for adverse clinical outcomes. Interventions: High-dose trivalent or standard-dose quadrivalent inactivated influenza vaccine, with revaccination up to 3 seasons. Results: Antibody data were available for 658 of 5260 randomized participants (12.5%; mean [SD] age, 66.2 [11.4] years; 507 male [77.1%], 151 female [22.9%]; 348 with heart failure [52.9%]). High-dose vaccine was associated with an increased magnitude in antibody titers for A/H1N1, A/H3N2, and B-type antigens compared with standard dose. More than 92% of all participants achieved seroprotection for each of the contained antigens, while seroconversion rates were higher in participants who received high-dose vaccine. Seroconversion for any antigen was not associated with the risk for cardiopulmonary hospitalizations or all-cause mortality (hazard ratio, 1.09; 95% CI, 0.79-1.53; P = .59), irrespective of randomized treatment (P = .38 for interaction). Conclusions and Relevance: High-dose vaccine elicited a more robust humoral response in patients with heart failure or prior myocardial infarction enrolled in the INVESTED trial, with no association between seroconversion status and the risk for cardiopulmonary hospitalizations or all-cause mortality. Vaccination to prevent influenza remains critical in high-risk populations. Trial Registration: ClinicalTrials.gov Identifier: NCT02787044.

4.
J Fungi (Basel) ; 10(3)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38535227

RESUMO

The fungal cell wall plays a critical role in regulating cellular integrity and communication, and serves as a frontline defense against stress. It is also a prime target for the development of antifungal agents. The cell wall is comprised of diverse polysaccharides and proteins and poses a challenging target for high-resolution structural characterization. Recently, the solid-state nuclear magnetic resonance (ssNMR) analysis of intact Aspergillus fumigatus cells has provided atomic-level insights into the structural polymorphism and functional assembly principles of carbohydrate components within the cell wall. This physical perspective, alongside structural information from biochemical assays, offers a renewed understanding of the cell wall as a highly complex and dynamic organelle. Here, we summarize key conceptual advancements in the structural elucidation of A. fumigatus mycelial and conidial cell walls and their responses to stressors. We also highlight underexplored areas and discuss the opportunities facilitated by technical advancements in ssNMR spectroscopy.

5.
Oncol Lett ; 27(5): 206, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38516683

RESUMO

Glioblastoma (GBM) is characterized by significant heterogeneity, leading to poor survival outcomes for patients, despite the implementation of comprehensive treatment strategies. The roles of cyclin A2 (CCNA2) and NIMA related kinase 2 (NEK2) have been extensively studied in numerous cancers, but their specific functions in GBM remain to be elucidated. The present study aimed to investigate the potential molecular mechanisms of CCNA2 and NEK2 in GBM. CCNA2 and NEK2 expression and prognosis in glioma were evaluated by bioinformatics methods. In addition, the distribution of CCNA2 and NEK2 expression in GBM subsets was determined using pseudo-time analysis and tricycle position of single-cell sequencing. Gene Expression Omnibus and Kyoto Encyclopedia of Genes and Genome databases were employed and enrichment analyses were conducted to investigate potential signaling pathways in GBM subsets and a nomogram was established to predict 1-, 2- and 3-year overall survival probability in GBM. CCNA2 and NEK2 expression levels were further validated by western blot analysis and immunohistochemical staining in GBM samples. High expression of CCNA2 and NEK2 in glioma indicates poor clinical outcomes. Single-cell sequencing of GBM revealed that these genes were upregulated in a subset of positive neural progenitor cells (P-NPCs), which showed significant proliferation and progression properties and may activate G2M checkpoint pathways. A comprehensive nomogram predicts 1-, 2- and 3-year overall survival probability in GBM by considering P-NPCs, age, chemotherapy and radiotherapy scores. CCNA2 and NEK2 regulate glioblastoma progression by targeting the cell cycle, thus indicating the potential of novel therapy directed to CCNA2 and NEK2 in GBM.

6.
Appl Radiat Isot ; 208: 111283, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38484590

RESUMO

A retrospective analysis of occupational exposure to ionizing radiation from medical uses and industrial uses in the three provinces of Central China from 2000 to 2021 was conducted. The average annual effective dose in medical uses and industrial uses decreased from 2.042 mSv and 2.334 mSv in 2000-2002 to 0.476 mSv and 0.371 mSv in 2021 respectively; the fraction of monitored workers receiving annual dose not exceeding 1 mSv increased from 60.78% and 74.45% in 2000-2002 to 94.20% and 96.85% in 2021 respectively, while receiving annual doses exceeding 20 mSv declined from 1.35% and 1.91% in 2000-2002 to 0.18% and 0.03% in 2021 respectively. The average annual effective dose and NR20 in the period 2000-2021 were relatively high in professional public health institutions (0.955 mSv and 0.004) and hospitals (0.815 mSv and 0.004). In 2021, the average annual effective dose to monitored workers in different occupational categories in medical uses in the three provinces of Central China were in the range of 0.199-0.692 mSv, with interventional radiology received the highest dose and NR20 (0.692 mSv and 0.005); the average annual effective dose ranged from 0.161 to 0.493 mSv in industrial uses, with industrial radiography received the highest dose and NR20 (0.493 mSv and 0.001). Occupational exposure in medical uses and industrial uses declined obviously in Central China, and the groups receiving higher doses are the radiation workers working in hospitals and professional public health institutions, or engaged in interventional radiology, nuclear medicine and industrial radiography, warranting more effective radiation protection measures.


Assuntos
Exposição Ocupacional , Exposição à Radiação , Monitoramento de Radiação , Humanos , Doses de Radiação , Monitoramento de Radiação/métodos , Estudos Retrospectivos , Radiação Ionizante , Exposição Ocupacional/análise , China
7.
Front Endocrinol (Lausanne) ; 15: 1340604, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444589

RESUMO

Aim: This study aimed to examine the association of liver enzymes, including alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl-transferase (GGT), with type 2 diabetes (T2D) risk, particularly their dose-response relationship. Methods: This cross-sectional study enrolled participants aged >20 years old who underwent physical examination at our local hospital from November 2022 to May 2023. A generalized additive model (GAM) was fit to assess the dose-response relationship between liver enzymes and T2D risk. Furthermore, data from the UK Biobank (n=217,533) and National Health and Nutrition Examination Survey (NHANES 2011-2018; n= 15,528) were analyzed to evaluate whether the dose-response relationship between liver enzymes and T2D differed by population differences. Results: A total of 14,100 participants were included (1,155 individuals with T2D and 12,945 individuals without diabetes) in the analysis. GAM revealed a non-linear relationship between liver enzymes and T2D risk (P non-linear < 0.001). Specifically, T2D risk increased with increasing ALT and GGT levels (range, <50 IU/L) and then plateaued when ALT and GGT levels were >50 IU/L. Elevated AST within a certain range (range, <35 IU/L) decreased the risk of T2D, whereas mildly elevated AST (>35 IU/L) became a risk factor for T2D. The UK Biobank and NHANES data analysis also showed a similar non-linear pattern between liver enzymes and T2D incidence. Conclusion: Liver enzymes were non-linearly associated with T2D risk in different populations, including China, the UK, and the US. Elevated ALT and GGT levels, within a certain range, could increase T2D risk. More attention should be given to liver enzyme levels for early lifestyle intervention and early T2D prevention. Further studies are necessary to explore the mechanism of the non-linear association between liver enzymes and T2D risk.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Adulto Jovem , Adulto , Diabetes Mellitus Tipo 2/epidemiologia , Inquéritos Nutricionais , Estudos Transversais , Alanina Transaminase , Fígado
8.
Discov Oncol ; 15(1): 72, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466508

RESUMO

BACKGROUND: GABPB1, the gene that encodes two isoforms of the beta subunit of GABP, has been identified as an oncogene in multiple malignant tumors. However, the role and mode of action of GABPB1 in malignant tumors, especially in lung cancer, are not well understood and need further research. METHODS: Our research focused on examining the biological function of GABPB1 in NSCLC (Non-Small Cell Lung Cancer). We analysed tumor data from public databases to assess the expression of GABPB1 in NSCLC  and its correlation with patient prognosis and investigated GABPB1 expression and methylation patterns in relation to the tumor microenvironment. In parallel, experiments were conducted using short hairpin RNA (shRNA) to suppress the GABPB1 gene in human lung cancer cells to evaluate the effects on cell proliferation, viability, and apoptosis. RESULTS: GABPB1 was widely expressed in various tissues of the human body. Compared to that in normal tissues, the expression of this gene was different in multiple tumor tissues. GABPB1 was highly expressed in lung cancer tissues and cell lines. Its expression was associated with molecular subtype and cellular signalling pathways, and a high level of GABPB1 expression was related to a poor prognosis in lung adenocarcinoma patients. The expression and methylation of GABPB1 affect the tumor microenvironment. After suppressing the expression of GABPB1 in both A549 and H1299 cells, we found a decrease in cell growth and expression, the formation of clones and an increase in the apoptosis rate. CONCLUSIONS: Our research verified that GABPB1 promotes the tumorigenesis of NSCLC and has an inhibitory effect on tumor immunity. The specific role of GABPB1 may vary among different pathological types of NSCLC. This molecule can serve as a prognostic indicator for lung adenocarcinoma, and its methylation may represent a potential breakthrough in treatment by altering the tumor immune microenvironment in lung squamous cell carcinoma. The role and mechanism of action of GABPB1 in NSCLC should be further explored.

9.
Adv Sci (Weinh) ; 11(15): e2304222, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342611

RESUMO

Tumor-associated macrophages (TAMs) play a crucial role in promoting tumor growth and dissemination, motivating a search for key targets to interfere with the activation of TAMs or reprogram TAMs into the tumor-suppressive type. To gain insight into the mechanisms of macrophage polarization, a designed co-culture system is established, allowing for the education of macrophages in a manner that closely mimics the intricacies of TAMs in the tumor immune microenvironment (TIME). Through database mining, exosomal miR-1246 is identified and is then validated. Exosomal miR-1246-driven polarization of TAMs disrupts the infiltration and function of CD8+ T cells. Mechanically, the amassment of exosomal miR-1246 stems from TUT7-mediated degradation of small noncoding RNA, a process stabilized by SNRPB, but not the precursor of miR-1246. Moreover, an Exo-motif is present in the exosomal miR-1246 sequence, enabling it to bind with the exosomal sorting protein hnRNPA2B1. RNA-seq analysis reveals that exogenous miR-1246 modulates the polarization of TAMs at a post-transcriptional level, emphasizing the pivotal role of the NLRP3 in macrophage polarization. In conclusion, the findings underscore the importance of exosomal miR-1246 as a trigger of macrophage reprogramming and uncover a novel mechanism for its enhanced presence in the TIME.


Assuntos
MicroRNAs , Macrófagos Associados a Tumor , Menogaril/metabolismo , Linfócitos T CD8-Positivos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Macrófagos/metabolismo
10.
Nat Commun ; 15(1): 986, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38307857

RESUMO

Microalgae are a renewable and promising biomass for large-scale biofuel, food and nutrient production. However, their efficient exploitation depends on our knowledge of the cell wall composition and organization as it can limit access to high-value molecules. Here we provide an atomic-level model of the non-crystalline and water-insoluble glycoprotein-rich cell wall of Chlamydomonas reinhardtii. Using in situ solid-state and sensitivity-enhanced nuclear magnetic resonance, we reveal unprecedented details on the protein and carbohydrate composition and their nanoscale heterogeneity, as well as the presence of spatially segregated protein- and glycan-rich regions with different dynamics and hydration levels. We show that mannose-rich lower-molecular-weight proteins likely contribute to the cell wall cohesion by binding to high-molecular weight protein components, and that water provides plasticity to the cell-wall architecture. The structural insight exemplifies strategies used by nature to form cell walls devoid of cellulose or other glycan polymers.


Assuntos
Chlamydomonas reinhardtii , Chlamydomonas , Chlamydomonas reinhardtii/metabolismo , Glicoproteínas/metabolismo , Parede Celular/metabolismo , Celulose/metabolismo , Água/metabolismo
11.
Natl Sci Rev ; 11(2): nwad149, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38213529

RESUMO

Gas diffusion electrodes (GDEs) mediate the transport of reactants, products and electrons for the electrocatalytic CO2 reduction reaction (CO2RR) in membrane electrode assemblies. The random distribution of ionomer, added by the traditional physical mixing method, in the catalyst layer of GDEs affects the transport of ions and CO2. Such a phenomenon results in elevated cell voltage and decaying selectivity at high current densities. This paper describes a pre-confinement method to construct GDEs with homogeneously distributed ionomer, which enhances mass transfer locally at the active centers. The optimized GDE exhibited comparatively low cell voltages and high CO Faradaic efficiencies (FE > 90%) at a wide range of current densities. It can also operate stably for over 220 h with the cell voltage staying almost unchanged. This good performance can be preserved even with diluted CO2 feeds, which is essential for pursuing a high single-pass conversion rate. This study provides a new approach to building efficient mass transfer pathways for ions and reactants in GDEs to promote the electrocatalytic CO2RR for practical applications.

12.
China CDC Wkly ; 6(2): 40-44, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38250701

RESUMO

What is already known about this topic?: Kashin-Beck disease (KBD) is a chronic and degenerative osteoarthropathy characterized by cartilage degeneration. It is an endemic disease that is highly prevalent among the Chinese population and poses a significant health risk. What is added by this report?: This is the first national report on the economic burden of KBD in China. According to the data from 2021, KBD has caused significant disease and economic burdens. The most substantial reduction in healthy life expectancy was observed among patients with degree II severity and those aged 60 years and older, resulting in a total indirect economic burden of 112.74 million Chinese Yuan (CNY). What are the implications for public health practice?: The results of this study will contribute to informing the development of tailored prevention and control strategies by the government. These strategies will include targeted policies and recommendations for appropriate healthcare and financial subsidies, which will be based on the demographic characteristics of the endemic areas.

13.
Proc Natl Acad Sci U S A ; 121(4): e2316724121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38232284

RESUMO

Photoelectrochemical (PEC) carbon dioxide (CO2) reduction (CO2R) holds the potential to reduce the costs of solar fuel production by integrating CO2 utilization and light harvesting within one integrated device. However, the CO2R selectivity on the photocathode is limited by the lack of catalytic active sites and competition with the hydrogen evolution reaction. On the other hand, serious parasitic light absorption occurs on the front-side-illuminated photocathode due to the poor light transmittance of CO2R cocatalyst films, resulting in extremely low photocurrent density at the CO2R equilibrium potential. This paper describes the design and fabrication of a photocathode consisting of crystal phase-modulated Ag nanocrystal cocatalysts integrated on illumination-reaction decoupled heterojunction silicon (Si) substrate for the selective and efficient conversion of CO2. Ag nanocrystals containing unconventional hexagonal close-packed phases accelerate the charge transfer process in CO2R reaction, exhibiting excellent catalytic performance. Heterojunction Si substrate decouples light absorption from the CO2R catalyst layer, preventing the parasitic light absorption. The obtained photocathode exhibits a carbon monoxide (CO) Faradaic efficiency (FE) higher than 90% in a wide potential range, with the maximum FE reaching up to 97.4% at -0.2 V vs. reversible hydrogen electrode. At the CO2/CO equilibrium potential, a CO partial photocurrent density of -2.7 mA cm-2 with a CO FE of 96.5% is achieved in 0.1 M KHCO3 electrolyte on this photocathode, surpassing the expensive benchmark Au-based PEC CO2R system.

14.
Stat Med ; 43(2): 216-232, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-37957033

RESUMO

In multi-season clinical trials with a randomize-once strategy, patients enrolled from previous seasons who stay alive and remain in the study will be treated according to the initial randomization in subsequent seasons. To address the potentially selective attrition from earlier seasons for the non-randomized cohorts, we develop an inverse probability of treatment weighting method using season-specific propensity scores to produce unbiased estimates of survival functions or hazard ratios. Bootstrap variance estimators are used to account for the randomness in the estimated weights and the potential correlations in repeated events within each patient from season to season. Simulation studies show that the weighting procedure and bootstrap variance estimator provide unbiased estimates and valid inferences in Kaplan-Meier estimates and Cox proportional hazard models. Finally, data from the INVESTED trial are analyzed to illustrate the proposed method.


Assuntos
Modelos Estatísticos , Humanos , Modelos de Riscos Proporcionais , Simulação por Computador , Pontuação de Propensão , Estimativa de Kaplan-Meier
15.
J Biopharm Stat ; 34(1): 111-126, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37224223

RESUMO

The restricted mean time in favor (RMT-IF) summarizes the treatment effect on a hierarchical composite endpoint with mortality at the top. Its crude decomposition into "stage-wise effects," i.e., the net average time gained by the treatment prior to each component event, does not reveal the patient state in which the extra time is spent. To obtain this information, we break each stage-wise effect into subcomponents according to the specific state to which the reference condition is improved. After re-expressing the subcomponents as functionals of the marginal survival functions of outcome events, we estimate them conveniently by plugging in the Kaplan -- Meier estimators. Their robust variance matrices allow us to construct joint tests on the decomposed units, which are particularly powerful against component-wise differential treatment effects. By reanalyzing a cancer trial and a cardiovascular trial, we acquire new insights into the quality and composition of the extra survival times, as well as the extra time with fewer hospitalizations, gained by the treatment in question. The proposed methods are implemented in the rmt package freely available on the Comprehensive R Archive Network (CRAN).

16.
Environ Toxicol ; 39(1): 106-119, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37665165

RESUMO

BACKGROUND: Total flavonoids of Rhizoma drynariae (TFRD) is broadly used in the treatment of orthopedic diseases. Nevertheless, the effects and underlying mechanism of TFRD on tendon-bone healing after anterior cruciate ligament reconstruction (ACLR) remain unclear. METHODS: The ACLR mouse model was established. Hematoxylin and Eosin (HE) staining was used for histological analysis of tendon-bone healing. Western blot was utilized to detect the levels of osteogenic related factors (ALP, OCN, RUNX2). The viability and alkaline phosphatase (ALP) activity of bone mesenchymal stem cells (BMSCs) were determined by Cell Counting Kit-8 (CCK-8) and ALP assays. The interaction of estrogen related receptor alpha (ESRRA), estrogen related receptor beta (ESRRB), and golgi-localized γ-ear containing ADP ribosylation factor-binding protein 1 (Gga1) was detected by luciferase reporter assays. The levels of important proteins on the TGF-ß/MAPK pathway were measured by western blot. RESULTS: TFRD improved tendon-bone healing, restored biomechanics of ACLR mice and activated the TGF-ß/MAPK pathway. TFRD treatment also enhanced the viability and osteogenic differentiation of BMSCs in vitro. Then, we demonstrated that TFRD targeted ESRRA and ESRRB to transcriptionally activate Gga1 expression. Knockdown of ESRRA, ESRRB, or Gga1 suppressed the viability and osteogenic differentiation of TFRD-induced BMSCs, which was revealed to be restored by Gga1 overexpression. The overexpression of ESRRA, ESRRB, or Gga1 was demonstrated to promote the BMSC viability and osteogenic differentiation. TGF-ß1 treatment can reverse the impact of Gga1 inhibition on osteogenic differentiation in TFRD-induced BMSCs. CONCLUSION: TFRD improves tendon-bone healing in ACLR mouse models and facilitates the osteogenic differentiation of BMSCs through the ERR1/2-Gga1-TGF-ß/MAPK pathway, which might deepen our understanding of the underlying mechanism of TFRD in tendon-bone healing.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Células-Tronco Mesenquimais , Polypodiaceae , Camundongos , Animais , Fator de Crescimento Transformador beta/metabolismo , Osteogênese , Polypodiaceae/metabolismo , Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Tendões/metabolismo , Células Cultivadas
17.
Magn Reson Chem ; 62(4): 298-309, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37724740

RESUMO

Solid-state nuclear magnetic resonance (ssNMR) measurements of intact cell walls and cellular samples often generate spectra that are difficult to interpret due to the presence of many coexisting glycans and the structural polymorphism observed in native conditions. To overcome this analytical challenge, we present a statistical approach for analyzing carbohydrate signals using high-resolution ssNMR data indexed in a carbohydrate database. We generate simulated spectra to demonstrate the chemical shift dispersion and compare this with experimental data to facilitate the identification of important fungal and plant polysaccharides, such as chitin and glucans in fungi and cellulose, hemicellulose, and pectic polymers in plants. We also demonstrate that chemically distinct carbohydrates from different organisms may produce almost identical signals, highlighting the need for high-resolution spectra and validation of resonance assignments. Our study provides a means to differentiate the characteristic signals of major carbohydrates and allows us to summarize currently undetected polysaccharides in plants and fungi, which may inspire future investigations.


Assuntos
Celulose , Polissacarídeos , Polissacarídeos/análise , Polissacarídeos/química , Espectroscopia de Ressonância Magnética , Celulose/análise , Celulose/química , Pectinas/análise , Pectinas/química , Imageamento por Ressonância Magnética , Parede Celular/química
18.
CNS Neurosci Ther ; 30(2): e14396, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37551838

RESUMO

Increasing evidence has revealed a strong connection between the aldehyde dehydrogenase family member ALDH1A3 and tumorigenesis, therapy resistance, and prognosis in diverse types of cancer. However, the specific miRNA involved in the pathways that regulate ALDH1A3-mediated glioblastoma (GBM) radioresistance remains to be elucidated. In this study, we demonstrated a high expression of ALDH1A3 in GBM cells, which plays a critical role in their proliferation and radioresistance. We also identified miR-4524b-5p, which is downregulated in GBM, as the ALDH1A3 upstream regulator. Overexpression of miR-4524b-5p reduced proliferation and radioresistance in GBM cells. Moreover, silencing ALDH1A3 reduced PI3K/AKT/mTOR signaling and glycolytic activity in GBM cells, whereas inhibiting mTOR reversed the radioresistance effects of ALDH1A3 on these cells. In vivo experiments have evidenced that ALDH1A3 silencing and miR-4524b-5p overexpression significantly reduced tumor growth and GBM cells radioresistance. In summary, targeting the miR-4524b-5p and ALDH1A3 axis is a promising therapeutic strategy for treating GBM.


Assuntos
Glioblastoma , MicroRNAs , Humanos , Glioblastoma/genética , Glioblastoma/radioterapia , Glioblastoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Regulação Neoplásica da Expressão Gênica
19.
Injury ; 55(2): 111212, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37984013

RESUMO

BACKGROUND: Rotator cuff tear (RCT) is the most common type of shoulder joint injury, platelet-rich plasma-derived exosomes (PRP-exos) are highly promising in tissue repair and regeneration. The purpose of this study was to determine the function of PRP-exos in rotator cuff tendon-bone healing. METHODS: PRP-exos were isolated from the rabbit whole blood by differential ultracentrifugation and characterized through transmission electron microscopy assay, nanoparticle tracking analysis, and western blotting. Alkaline phosphatase and Von Kossa staining were used to show tendon-derived stem cell (TDSC) differentiation. RT-qPCR and western blotting were performed to detect COL II, SOX-9, and TIMP-1. To determine the therapeutic effects of PRP-exos in vivo. Thirty New Zealand white rabbits were divided into control, model, and PRP-exos groups. The RCT animal model was constructed. The changes in tendon-bone tissue were determined by HE staining. Contents of COL-II, SOX-9, and TIMP-1 were determined by immunohistochemistry staining. RESULTS: PRP-exos were successfully isolated from rabbit blood. PRP-exos promoted TDSC proliferation and differentiation and also induced tendon-specific markers COL II, SOX-9, and TIMP-1 production. In vivo study revealed that PRP-exos promoted early healing of injured tendons. Rabbits treated with PRP-exos had better tissue arrangement in the tear site. Additionally, the contents of COL II, SOX-9, and TIMP-1 were also increased in the RCT rabbit model after PRP-exos treatment. CONCLUSIONS: PRP-exos enhanced tendon-bone healing by promoting TDSC proliferation and differentiation. This finding indicates that PRP-exos can serve as a promising strategy to treat rotator cuff tendon-bone healing.


Assuntos
Exossomos , Plasma Rico em Plaquetas , Lesões do Manguito Rotador , Lesões do Ombro , Coelhos , Animais , Manguito Rotador , Inibidor Tecidual de Metaloproteinase-1/análise , Tendões , Lesões do Manguito Rotador/terapia
20.
Adv Mater ; 36(8): e2307741, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37813568

RESUMO

Efficient catalyst design is crucial for addressing the sluggish multi-step sulfur redox reaction (SRR) in lithium-sulfur batteries (LiSBs), which are among the promising candidates for the next-generation high-energy-density storage systems. However, the limited understanding of the underlying catalytic kinetic mechanisms and the lack of precise control over catalyst structures pose challenges in designing highly efficient catalysts, which hinder the LiSBs' practical application. Here, drawing inspiration from the theoretical calculations, the concept of precisely controlled pre-lithiation SRR electrocatalysts is proposed. The dual roles of channel and surface lithium in pre-lithiated 1T'-MoS2 are revealed, referred to as the "electronic modulation effect" and "drifting effect", respectively, both of which contribute to accelerating the SRR kinetics. As a result, the thus-designed 1T'-Lix MoS2 /CS cathode obtained by epitaxial growth of pre-lithiated 1T'-MoS2 on cubic Co9 S8 exhibits impressive performance with a high initial specific capacity of 1049.8 mAh g-1 , excellent rate-capability, and remarkable long-term cycling stability with a decay rate of only 0.019% per cycle over 1000 cycles at 3 C. This work highlights the importance of precise control in pre-lithiation parameters and the synergistic effects of channel and surface lithium, providing new valuable insights into the design and optimization of SRR electrocatalysts for high-performance LiSBs.

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