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1.
J Cell Mol Med ; 28(16): e70003, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39153207

RÉSUMÉ

Pulmonary hypertension (PH) is a chronic progressive vascular disease characterized by abnormal pulmonary vascular resistance and pulmonary artery pressure. The major structural alteration during PH is pulmonary vascular remodelling, which is mainly caused by the imbalance between proliferation and apoptosis of pulmonary vascular cells. Previously, it was thought that apoptosis was the only type of programmed cell death (PCD). Soon afterward, other types of PCD have been identified, including autophagy, pyroptosis, ferroptosis and necroptosis. In this review, we summarize the role of the above five forms of PCD in mediating pulmonary vascular remodelling, and discuss their guiding significance for PH treatment. The current review could provide a better understanding of the correlation between PCD and pulmonary vascular remodelling, contributing to identify new PCD-associated drug targets for PH.


Sujet(s)
Apoptose , Hypertension pulmonaire , Remodelage vasculaire , Humains , Hypertension pulmonaire/anatomopathologie , Hypertension pulmonaire/physiopathologie , Animaux , Nécroptose , Transduction du signal , Autophagie , Ferroptose , Artère pulmonaire/anatomopathologie , Artère pulmonaire/métabolisme , Pyroptose
2.
J Am Chem Soc ; 146(32): 22348-22359, 2024 Aug 14.
Article de Anglais | MEDLINE | ID: mdl-39088418

RÉSUMÉ

Sonopiezoelectric therapy, an ultrasound-activated piezoelectric nanomaterial for tumor treatment, has emerged as a novel alternative modality. However, the limited piezoelectric catalytic efficiency is a serious bottleneck for its practical application. Excellent piezoelectric catalysts with high piezoelectric coefficients, good deformability, large mechanical impact surface area, and abundant catalytically active sites still need to be developed urgently. In this study, the classical ferroelectric material, bismuth titanate (Bi4Ti3O12, BTO), is selected as a sonopiezoelectric sensitizer for tumor therapy. BTO generates electron-hole pairs under ultrasonic irradiation, which can react with the substrates in a sonocatalytic-driven redox reaction. Aiming to further improve the catalytic activity of BTO, modification of surface oxygen vacancies and treatment of corona polarization are envisioned in this study. Notably, modification of the surface oxygen vacancies reduces its bandgap and inhibits electron-hole recombination. Additionally, the corona polarization treatment immobilized the built-in electric field on BTO, further promoting the separation of electrons and holes. Consequently, these modifications greatly improve the sonocatalytic efficiency for in situ generation of cytotoxic ROS and CO, effectively eradicating the tumor.

3.
Turk J Gastroenterol ; 35(6): 440-452, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-39128103

RÉSUMÉ

BACKGROUND/AIMS:  Although endoscopic resection is an effective treatment of rectal neuroendocrine neoplasms (R-NENs) with low malignant potential, there is no consensus on the most recommended endoscopic method. This study aimed to assess the efficacy and acceptability of different endoscopic treatments for R-NENs with low malignant potential. MATERIALS AND METHODS:  We searched databases for studies on treatments of R-NENs using endoscopic resection. These studies comprised techniques such as endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), modified endoscopic mucosal resection (EMRM), modified endoscopic submucosal dissection (ESDM), and transanal endoscopic microsurgery (TEM). The primary outcomes assessed were histological complete resection (HCR). RESULTS:  Overall, 38 retrospective studies (3040 R-NENs) were identified. Endoscopic mucosal resection with a cap (EMRC), endoscopic mucosal resection with ligation (EMRL), ESD, ESDM, and TEM demonstrated higher resectability than did EMR in achieving HCR. Endoscopic mucosal resection, EMRC, EMRL, EMRP, EMRD, and EMRU required shorter operation times than did ESD. Endoscopic mucosal resection, EMRC, ESDM, and TEM incurred lower risks than did ESD. CONCLUSION:  Regarding R-NENs <20 mm with low malignant potential, ESD could be used as the primary treatment. However, TEM may be more effective if supported by economic conditions and hospital facility. With respect to R-NENs <16 mm with low malignant potential, EMRL could be used as the primary treatment. In regard to R-NENs <10 mm with low malignant potential, EMRL, EMRC, and ESD could be used as the primary treatment. However, EMRL and EMRC might be better when operational difficulties and economic conditions were considered.


Sujet(s)
Mucosectomie endoscopique , Tumeurs neuroendocrines , Tumeurs du rectum , Humains , Tumeurs du rectum/chirurgie , Tumeurs du rectum/anatomopathologie , Mucosectomie endoscopique/méthodes , Tumeurs neuroendocrines/chirurgie , Tumeurs neuroendocrines/anatomopathologie , Résultat thérapeutique , Méta-analyse en réseau , Microchirurgie endoscopique transanale/méthodes , Mâle , Femelle , Études rétrospectives , Adulte d'âge moyen , Durée opératoire , Sujet âgé
4.
Huan Jing Ke Xue ; 45(8): 4904-4914, 2024 Aug 08.
Article de Chinois | MEDLINE | ID: mdl-39168706

RÉSUMÉ

Microbial communities play an important role in water quality regulation and biogeochemical cycles in lakes, and their community structure and function are affected by environmental factors. Therein, antibiotics affect the abundance, diversity, composition, and function of microbial communities. In this study, Baiyangdian Lake was selected as the study area. Sediment samples of 16 sites were collected in August 2018 and April 2019, respectively. Ultra-high performance liquid chromatography-mass spectrometry (HPLC-MS/MS) was used to determine the content of typical antibiotics-quinolones (QNs) in sediment. Through high-throughput sequencing technology, the structure and function of microbial communities was analyzed in the sediments to explore the spatiotemporal variation. Thereinto, redundancy analysis (RDA) was used to identify the key influencing factors of spatiotemporal variation of microbial communities. The results showed that: ① From August to April, the average ω(QNs) showed an increasing trend, and its mean value changed from 3.91 ng·g-1 to 6.34 ng·g-1, with significant seasonal differences in oxolinic acid (OXO) and total QNs content (P < 0.05). ② In terms of temporal variation, the dominant bacteria were Proteobacteria and Chloroflexi. The relative abundance of Proteobacteria showed a decreasing trend, whereas Chloroflexi showed an increasing trend; at the genus level, the dominant bacteria genera in August were norank_ f__Anaerolineaceae and Thiobacilus, and the dominant bacteria genera in April were Acinetobacter and norank_ f_Anaerolineaceae, and the dominant bacteria genera had significant seasonal differences (P < 0.05). ③ In terms of temporal variation, the index of Simpson, Chao, Ace, and OTU number all showed an increasing trend, and the seasonal differences were significant (P < 0.05). ④ In terms of spatial variation, there were no significant spatial differences among functional genes of COG. In terms of temporal variation, there were significant seasonal differences in functional genes of energy production and conversion, carbohydrate transport and metabolism, transcription, cell wall/membrane/envelope biogenesis, and signal transduction mechanisms (P < 0.01 and P < 0.05). ⑤ Microbial community structure and functional genes were significantly correlated with QNs (P < 0.01 and P < 0.05), and QNs were the main influencing factors. Therefore, QNs were the main factor affecting the changes in microbial community structure and functional genes in sediments of Baiyangdian Lake. Thus, comprehensive control of antibiotic pollution in sediments should be further strengthened.


Sujet(s)
Antibactériens , Sédiments géologiques , Lacs , Microbiote , Polluants chimiques de l'eau , Lacs/microbiologie , Sédiments géologiques/microbiologie , Microbiote/génétique , Chine , Polluants chimiques de l'eau/analyse , Surveillance de l'environnement , Quinolinone/analyse , Bactéries/classification , Bactéries/génétique
6.
Org Lett ; 26(32): 6819-6824, 2024 Aug 16.
Article de Anglais | MEDLINE | ID: mdl-39106047

RÉSUMÉ

With alanine as a transient directing group, Pd-catalyzed regioselective alkynylation at the indole C4-position was successfully established in a good yield. The total synthesis of the PAF antagonist demonstrated the synthetic utility of this protocol. The regioselectivity was explicitly proven by the prepared C4-selective palladacycle intermediate in the catalytic process and the DFT calculation of the energy barriers of C4- and C2-site-selective C-H activation of indole.

7.
Rev Cardiovasc Med ; 25(6): 226, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-39076311

RÉSUMÉ

Background: Cardiogenic shock (CS) is a critical illness with a high mortality rate in clinical practice. Although some biomarkers have been found to be associated with mortality in patients suffering from CS in previous studies. The albumin-corrected anion gap (ACAG) has not been studied in depth. Our study aimed to explore the relationship between ACAG and mortality in patients with CS. Methods: All baseline data was extracted from Medical Information Mart for Intensive Care-IV version: 2.0 (MIMIC-IV). According to the prognosis at 30 days of follow-up, they were divided into survivors and non-survivors groups. The survival curves between the two groups were drawn using the Kaplan-Meier method and the log-rank test. Valid factors were selected using the least absolute shrinkage and selection operator (LASSO) logistic analysis model. Analysis was performed to investigate the relationship between mortality and all enrolled patients using restricted cubic spline (RCS) and Cox proportional hazards models. Receiver operating characteristic (ROC) curves were used to assess the predictive ability of ACAG. Evaluation of final result stability using sensitivity analysis. Results: 839 cases were selected to meet the inclusion criteria and categorized into survivors and non-survivors groups in the final analysis. The ACAG value measured for the first time at the time of admission was selected as the research object. Kaplan-Meier (K-M) survival curves showed that cumulative 30- and 90-day survival decreased progressively with elevated ACAG (p < 0.001), and multifactorial Cox regression analyses showed ACAG to be an independent risk factor for increased 30- and 90-day mortality in patients suffering from CS (p < 0.05). RCS curves revealed that all-cause mortality in this group of patients increased with increasing ACAG ( χ 2 = 5.830, p = 0.120). The ROC curve showed that the best cutoff value for ACAG for predicting 30-day mortality in patients with CS was 22.625, with a sensitivity of 44.0% and a specificity of 74.7%. The relationship between ACAG and CS short-term mortality remained stable in all sensitivity analyses (All p < 0.05). Conclusions: The ACAG is an independent risk factor for 30- and 90-day mortality in CS patients and predicts poor clinical outcomes in CS patients. According to our study, elevated ACAG at admission, especially when ACAG > 20 mmol/L, was an independent predictor of all-cause mortality in CS.

8.
Rev Cardiovasc Med ; 25(2): 65, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-39077353

RÉSUMÉ

Background: Cardiac arrest (CA) is a common event in the intensive care unit (ICU), which seriously threatens the prognosis of patients. Therefore, it is crucial to determine a simple and effective clinical indicator to judge the prognosis of patients after a CA for later treatments. The purpose of this study was to investigate the relationship between the lactate dehydrogenase to albumin ratio (LAR) and the prognosis of patients after a CA. Methods: The clinical data of participants was obtained from the Medical Information Mart for Intensive Care IV (MIMIC-IV, v2.0; 2008 to 2019). According to the 30-day prognosis, patients were divided into a survivors group (n = 216) and a non-survivors group (n = 304). The optimal LAR threshold was determined using restricted cubic spline (RCS), which divided patients into a high LAR group ( ≥ 15.50, n = 257) and a low LAR group ( < 15.50, n = 263). The ICU hospitalization and 30-day accumulative survival curves of the two groups were plotted following the Kaplan-Meier survival analysis. Multivariate Cox regression was used to analyze the relationship between the LAR and the prognosis of CA patients. Receiver operating characteristic (ROC) curves were drawn to evaluate the predictive efficacy of the LAR on 30-day all-cause mortality, and sensitivity analysis was used to check the reliability of the findings. Results: A total of 520 patients with CA were enrolled and the 30-day mortality was 58.46%. The LAR in the non-survivors group was higher than in the survivors group. The RCS showed a linear trend relationship between the LAR and the mortality risk in patients during their ICU stay and 30 days; moreover, as the LAR increased, so did the risk of mortality. The Kaplan-Meier survival curve showed that compared with the low LAR group, the cumulative survival rates of ICU hospitalization and 30 days were lower in the high LAR group among CA patients (p < 0.001). Multivariate Cox regression analysis showed that an elevated LAR ( ≥ 15.50) was an independent risk factor for mortality during ICU stay and 30 days (p < 0.005). ROC analysis suggested that the LAR was superior to the sequential organ failure assessment (SOFA) score in predicting the 30-day all-cause mortality in CA patients (area under the curve (AUC) = 0.676, 95% confidence interval [CI]: 0.629-0.723). To verify the reliability of our findings, we performed sensitivity analyses and found that the findings were reliable. Conclusions: An elevated LAR might be a predictor of mortality in patients following a CA during ICU hospitalization and 30 days, thereby it can be used to provide a reference for the clinical management of these patients.

9.
J Colloid Interface Sci ; 676: 783-794, 2024 Jul 22.
Article de Anglais | MEDLINE | ID: mdl-39067214

RÉSUMÉ

In tumor therapy, copper (Cu)-based nanozymes with peroxidase-like activity play a crucial role in converting hydrogen peroxide into hydroxyl radicals (OH). This process induces immunogenic cell death, which in turn activates the body's immune response, enhancing the efficacy of tumor immunotherapy. Nonetheless, the efficiency of this reaction is curtailed due to the oxidation of Cu(I) to Cu(II), leading to the self-depletion of the nanozyme's activity and an insufficient yield of OH for effective immunotherapeutic activation. To surmount this challenge, our research introduces a photocharging self-doped semiconductor nanozyme, copper sulfide (Cu9S8). The photocharging effect enables the nanozyme to convert internal Cu(II) back to Cu(I) through charge transfer induced by near-infrared (NIR)-II photothermal energy, thereby effectively maintaining the enzyme-like activity of the nanozyme. Additionally, Cu9S8 is enhanced with a calcium sulfide (CaS) coating. This coating reacts in the acidic microenvironment of tumors to generate hydrogen sulfide (H2S) gas, which in turn suppresses the catalase activity inherent in tumor cells, ensuring a plentiful supply of H2O2 for the nanozyme's operation. This dual strategy of amplifying enzyme-like activity and substrate availability culminates in the generation of ample OH within tumor cells, leading to significant immunogenic cell death and thereby realizing potent immunotherapy.

10.
iScience ; 27(7): 110163, 2024 Jul 19.
Article de Anglais | MEDLINE | ID: mdl-38974966

RÉSUMÉ

Aging-related cardiac fibrosis represents the principal pathological progression in cardiovascular aging. The Muscleblind-like splicing regulator 2 (MBNL2) has been unequivocally established as being associated with cardiovascular diseases. Nevertheless, its role in aging-related cardiac fibrosis remains unexplored. This investigation revealed an elevation of MBNL2 levels in the aged heart and senescent cardiac fibroblasts. Notably, the inhibition of MBNL2 demonstrated a capacity to mitigate H2O2-induced myofibroblast transformation and aging-related cardiac fibrosis. Further mechanistic exploration unveiled that aging heightened the expression of SENP1 and impeded the SUMO1 binding with KLF4, and SUMOylation of KLF4 effectively increased by the inhibition of MBNL2. Additionally, the inhibition of TGF-ß1/SMAD3 signaling attenuated the impact of over-expression of MBNL2 in inducing senescence and cardiac fibrosis. MBNL2, by orchestrating SUMOylation of KLF4, upregulating the TGF-ß1/SMAD3 signaling pathway, emerges as a significant promoter of aging-related cardiac fibrosis. This discovery identifies a novel regulatory target for managing aging-related cardiac fibrosis.

11.
Int J Biol Macromol ; : 134151, 2024 Jul 24.
Article de Anglais | MEDLINE | ID: mdl-39059534

RÉSUMÉ

Japanese encephalitis (JE), a mosquito-borne zoonotic disease caused by the Japanese encephalitis virus (JEV), poses a serious threat to global public health. The low viremia levels typical in JEV infections make RNA detection challenging, necessitating early and rapid diagnostic methods for effective control and prevention. This study introduces a novel one-pot detection method that combines recombinant enzyme polymerase isothermal amplification (RPA) with CRISPR/EsCas13d targeting, providing visual fluorescence and lateral flow assay (LFA) results. Our portable one-pot RPA-EsCas13d platform can detect as few as two copies of JEV nucleic acid within 1 h, without cross-reactivity with other pathogens. Validation against clinical samples showed 100 % concordance with real-time PCR results, underscoring the method's simplicity, sensitivity, and specificity. This efficacy confirms the platform's suitability as a novel point-of-care testing (POCT) solution for detecting and monitoring the JE virus in clinical and vector samples, especially valuable in remote and resource-limited settings.

12.
Heliyon ; 10(13): e33785, 2024 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-39044992

RÉSUMÉ

Background and aims: Postoperative atrial fibrillation (POAF) is a frequent complication following cardiac surgery and is associated with adverse clinical outcomes. Our study aimed at determining the clinical and echocardiographic predictors of POAF in patients with cardiac surgery and management of this group of patients may improve their outcome. Methods: We prospectively enrolled patients from the department of cardiovascular surgery in the Second Hospital of Tianjin Medical University from October 23, 2020 to October 30, 2022, without a history of atrial fibrillation. Cox regression was used to identify significant predictors of POAF. Results: A total of 217 patients (79 [36.41 %] were female, 63.96 ± 12.32 years) were included. 88 (40.55 %) patients met the criteria for POAF. Cox regression showed that preoperative left atrial diameter (LAD) (HR: 1.040, 95 % CI 1.008-1.073, p = 0.013) and postoperative QRS/LVEDD (HR: 0.398, 95 % CI 0.193-0.824, p = 0.013) and E/e' (HR: 1.029, 95 % CI 1.002-1.057,p = 0.033) were predictors of POAF. Conclusion: Preoperative LAD and postoperative QRS/LVEDD and E/e' were predictors of POAF in patients undergoing cardiac surgery. Trial registration site: http://www.chictr.org.cn. Registration number: ChiCTR2200063344.

13.
Acta Pharm Sin B ; 14(7): 3125-3139, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39027250

RÉSUMÉ

Zhigancao decoction is a traditional prescription for treating irregular pulse and palpitations in China. As the monarch drug of Zhigancao decoction, the bioactive molecules of licorice against heart diseases remain elusive. We established the HRESIMS-guided method leading to the isolation of three novel bicyclic peptides, glycnsisitins A-C (1-3), with distinctive C-C and C-O-C side-chain-to-side-chain linkages from the roots of Glycyrrhiza uralensis (Licorice). Glycnsisitin A demonstrated stronger cardioprotective activity than glycnsisitins B and C in an in vitro model of doxorubicin (DOX)-induced cardiomyocyte injury. Glycnsisitin A treatment not only reduced the mortality of heart failure (HF) mice in a dose-dependent manner but also significantly attenuated DOX-induced cardiac dysfunction and myocardial fibrosis. Gene set enrichment analysis (GSEA) of the differentially expressed genes indicated that the cardioprotective effect of glycnsisitin A was mainly attributed to its ability to maintain iron homeostasis in the myocardium. Mechanistically, glycnsisitin A interacted with transferrin and facilitated its binding to the transferrin receptor (TFRC), which caused increased uptake of iron in cardiomyocytes. These findings highlight the key role of bicyclic peptides as bioactive molecules of Zhigancao decoction for the treatment of HF, and glycnsisitin A constitutes a promising therapeutic agent for the treatment of HF.

14.
Small ; : e2310964, 2024 Jul 19.
Article de Anglais | MEDLINE | ID: mdl-39030863

RÉSUMÉ

Photodynamic therapy (PDT) is long-standing suffered from elevated tumor interstitial fluid pressure (TIFP) and prevalent hypoxic microenvironment within the solid malignancies. Herein, sound-activated flexocatalysis is developed to overcome the dilemma of PDT through both enhancing tumor penetration of photosensitizers by reducing TIFP and establishing an oxygen-rich microenvironment. In detail, a Schottky junction is constructed by flexocatalyst MoSe2 nanoflowers and Pt. Subsequently, the Schottky junction is loaded with the photosensitizer indocyanine green (ICG) and encapsulated within tumor cytomembrane to constitute a bionic-flexocatalytic nanomedicine (MPI@M). After targeting the tumor, MPI@M orchestrates flexocatalytic water splitting in tumor interstitial fluid under acoustic stimulation to lower TIFP, which boosted the tumor penetration of ICG. Concurrently, the oxygen released from the flexocatalytic water splitting overcomes the limitation of hypoxia against PDT. Furthermore, superfluous singlet oxygen generated by PDT can induce mitochondrial dysfunction for further tumor cell apoptosis. After 60 min of flexocatalysis, both the 30% decrease of TIFP and the relieved tumor hypoxia are observed, significantly promoting the therapeutic effect of PDT. Consequently, MoSe2/Pt junction nanoflowers, with the excellent flexocatalytic performance, hold significant potential for future applications in biocatalytic cancer therapies.

15.
Chem Sci ; 15(27): 10625-10637, 2024 Jul 10.
Article de Anglais | MEDLINE | ID: mdl-38994408

RÉSUMÉ

Solar CO2 reduction to renewable hydrocarbon fuels offers a promising pathway to carbon neutrality, but it is retarded by tough CO2 activation, complicated mechanisms, sluggish charge transport kinetics, and a scarcity of strategies for precise tuning of charge transport pathways. Herein, we first conceptually design a novel insulating polymer-mediated electron-tunneling artificial photosystem via progressive interface configuration regulation, wherein tailor-made Ag@citrate nanocrystals (NCs) are controllably self-assembled on transition metal chalcogenides (TMCs) assisted by an ultrathin insulating polymer interim layer, i.e., poly(allylamine hydrochloride) (PAH). In this multilayered nano-architecture, a solid ultra-thin insulating PAH interim layer serves as an unexpected charge tunneling mediator to stimulate smooth electron transfer from the TMC substrate to the terminal electron reservoirs of Ag@citrate NCs, engendering the tandem charge transfer route and significantly boosting the visible-light-driven photocatalytic CO2-to-syngas conversion performances. Furthermore, we have ascertained that such TMC-insulating polymer-metal NC tunneling photosystems are universal. This study would spark new inspiration for unleashing the long-term neglected charge tunneling capability of insulating polymers and diversifying non-conjugated polymer-based artificial photosystems for solar-to-fuel energy conversion.

17.
Medicine (Baltimore) ; 103(28): e38400, 2024 Jul 12.
Article de Anglais | MEDLINE | ID: mdl-38996165

RÉSUMÉ

The study investigated the health care workers' knowledge, attitudes, and practice levels regarding occupational protection against antineoplastic drugs (ADs) via analysis of latent classes and their influencing factors. A convenience sampling method was used to select healthcare workers from 7 hospitals in southern China between April and August 2023. A questionnaire based on literature analysis, brainstorming, and Delphi method was used to investigate the knowledge, practice, and attitudes of healthcare workers exposed to ADs for appropriate occupational protection intervention, followed by latent class analysis. The factors influencing latent classes were identified via single-factor analysis and multiple logistic regression. A total of 322 healthcare workers from departments using ADs were surveyed. The knowledge score associated with occupational protection against ADs was 31.95 ±â€…7.38. The attitude score was 21.08 ±â€…2.729, while the practice score was 36.54 ±â€…9.485. The overall score was 89.57 ±â€…15.497. The healthcare workers were divided into 4 latent classes based on their knowledge, attitude, and practice associated with occupational protection measures against ADs. Healthcare workers in the 4 categories showed significance differences based on professional title, marital status, educational background, and frequency of exposure to ADs (P < .05). The knowledge, attitude, and practice levels of healthcare workers engaged in ADs at work can be divided into 4 latent classes. Despite their increased awareness of the hazards associated with ADs and their attitudes toward protection, the healthcare workers displayed poor knowledge and implementation of occupational protection measures.


Sujet(s)
Antinéoplasiques , Connaissances, attitudes et pratiques en santé , Personnel de santé , Analyse de structure latente , Exposition professionnelle , Humains , Exposition professionnelle/effets indésirables , Exposition professionnelle/statistiques et données numériques , Exposition professionnelle/prévention et contrôle , Études transversales , Femelle , Mâle , Adulte , Antinéoplasiques/effets indésirables , Personnel de santé/statistiques et données numériques , Personnel de santé/psychologie , Facteurs de risque , Chine , Enquêtes et questionnaires , Adulte d'âge moyen , Attitude du personnel soignant
18.
Small ; : e2403850, 2024 Jul 16.
Article de Anglais | MEDLINE | ID: mdl-39011977

RÉSUMÉ

Boosting the biomimetic catalytic activity of nanozyme is important for its potential application. One common strategy to achieve this goal mainly focused on manipulating the electronic state of metal site through the first coordination shell to modulate the adsorption/desorption strength of related reactant, intermediate and/or product, but remained challenging. Taking Cu-based catecholase-mimicking nanozyme for example, this work herein reports a different strategy involving amino-induced modulation of electronic state through the second shell to raise the electron density of Cu site, which further triggers the repulsion effect between neighboring geminal Cu centers to increase the Cu─Cu distance. The resulting nanozyme with electron-rich Cu site (DT-Cu) presents a lower work function and an upshifted d-band center in comparison with its counterpart (i.e., relatively electron-deficient TA-Cu), which promotes the electron transfer and enhances the adsorption strengths of Cu site for O2, catechol and H2O2 intermediate. The longer Cu─Cu distance of DT-Cu accelerated the O─O bond dissociation of H2O2 intermediate. This expedites the oxygen reduction process during catecholase-like catalysis, which together with the enhanced O2/H2O2/catechol adsorption corporately boosts the catecholase-like activity of DT-Cu.

19.
Elife ; 122024 Jul 26.
Article de Anglais | MEDLINE | ID: mdl-39056282

RÉSUMÉ

The evolutionary conservation of non-core RAG regions suggests significant roles that might involve quantitative or qualitative alterations in RAG activity. Off-target V(D)J recombination contributes to lymphomagenesis and is exacerbated by RAG2' C-terminus absence in Tp53-/- mice thymic lymphomas. However, the genomic stability effects of non-core regions from both Rag1c/c and Rag2c/c in BCR-ABL1+ B-lymphoblastic leukemia (BCR-ABL1+ B-ALL), the characteristics, and mechanisms of non-core regions in suppressing off-target V(D)J recombination remain unclear. Here, we established three mouse models of BCR-ABL1+ B-ALL in mice expressing full-length RAG (Ragf/f), core RAG1 (Rag1c/c), and core RAG2 (Rag2c/c). The Ragc/c (Rag1c/c and Rag2c/c) leukemia cells exhibited greater malignant tumor characteristics compared to Ragf/f cells. Additionally, Ragc/c cells showed higher frequency of off-target V(D)J recombination and oncogenic mutations than Ragf/f. We also revealed decreased RAG cleavage accuracy in Ragc/c cells and a smaller recombinant size in Rag1c/c cells, which could potentially exacerbate off-target V(D)J recombination in Ragc/c cells. In conclusion, these findings indicate that the non-core RAG regions, particularly the non-core region of RAG1, play a significant role in preserving V(D)J recombination precision and genomic stability in BCR-ABL1+ B-ALL.


Sujet(s)
Protéines de liaison à l'ADN , Protéines de fusion bcr-abl , Protéines à homéodomaine , Recombinaison V(D)J , Animaux , Protéines à homéodomaine/génétique , Protéines à homéodomaine/métabolisme , Recombinaison V(D)J/génétique , Protéines de fusion bcr-abl/génétique , Protéines de fusion bcr-abl/métabolisme , Souris , Protéines de liaison à l'ADN/génétique , Protéines de liaison à l'ADN/métabolisme , Modèles animaux de maladie humaine , Carcinogenèse/génétique , Humains , Leucémie-lymphome lymphoblastique à précurseurs B/génétique , Leucémie-lymphome lymphoblastique à précurseurs B/anatomopathologie , Leucémie-lymphome lymphoblastique à précurseurs B/métabolisme
20.
Biosens Bioelectron ; 261: 116495, 2024 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-38878699

RÉSUMÉ

In this study, we have for the first time constructed a ratiometric ECL biosensor for the ultrasensitive detection of microRNAs (miRNAs) using gold nanoparticles (Au NPs) to trigger both the low-potential emission from conjugated polymer poly(9,9-dioctylfluorene-2,7-diyl) dots (PFO Pdots) and the LSPR-ECL effect with sulfur-doped boron nitride quantum dots (S-BN QDs). PFO Pdots were first applied to the Au NPs-modified electrode, followed by covalent binding to capture the hairpin H1. Immediately thereafter, a small amount of miRNA-141 was able to generate a large amount of output DNA (OP) by traversing the target cycle. OP, H3-S-BN QDs, and H4-glucose oxidase (H4-GOD) were then added sequentially to the Au NPs-modified electrode surface, and the hybridization chain reaction (HCR) was initiated. This resulted in the introduction of a large amount of GOD into the system, which catalyzed the in situ formation of the co-reactant hydrogen peroxide (H2O2) from the substrate glucose. Due to the electron transfer effect, the production of H2O2 led to the ECL quenching of PFO Pdots. Meanwhile, H2O2 served as a co-reactant of S-BN QDs, resulting in strong ECL emission of S-BN QDs at the cathode. Furthermore, the cathodic ECL intensity of S-BN QDs was further enhanced by an LSPR-ECL mechanism between Au NPs and S-BN QDs. By measuring the ratio of ECL intensities at two excitation potentials, this approach could provide sensitive and reliable detection of miRNA-141 in the range of 0.1 fM ∼10 nM, with a detection limit of 0.1 fM.


Sujet(s)
Techniques de biocapteur , Techniques électrochimiques , Or , Limite de détection , Mesures de luminescence , Nanoparticules métalliques , microARN , Boîtes quantiques , Techniques de biocapteur/méthodes , Or/composition chimique , microARN/analyse , Nanoparticules métalliques/composition chimique , Boîtes quantiques/composition chimique , Techniques électrochimiques/méthodes , Humains , Mesures de luminescence/méthodes , Fluorènes/composition chimique , Glucose oxidase/composition chimique , Peroxyde d'hydrogène/composition chimique
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