Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 740
Filtrar
Más filtros

Base de datos
Tipo del documento
Intervalo de año de publicación
1.
Phys Chem Chem Phys ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39229763

RESUMEN

Despite the important role of the dark 1nπ* state in the photostability of thymidine in aqueous solution, no detailed ultraviolet (UV) wavelength-dependent investigation of the 1nπ* quantum yield (QY) in aqueous thymidine has been experimentally performed. Here, we investigate the wavelength-dependent photoemission spectra of aqueous thymidine from 266.7 to 240 nm using liquid-microjet photoelectron spectroscopy. Two observed ionization channels are assigned to resonant ionizations from 1ππ* to the cationic ground state D0 (π-1) and 1nπ* to the cationic excited state D1 (n-1). The weak 1nπ* → D1 ionization channel appears due to ultrafast 1ππ* → 1nπ* internal conversion within the pulse duration of ∼180 fs. The obtained 1nπ* quantum yields exhibit a strong wavelength dependence, ranging from 0 to 0.27 ± 0.01, suggesting a hitherto uncharacterized 1nπ* feature. The corresponding vertical ionization energies (VIEs) of D0 and D1 of aqueous thymidine are experimentally determined to be 8.47 ± 0.12 eV and 9.22 ± 0.29 eV, respectively. Our UV wavelength-dependent QYs might indicate that different structural critical points to connect the multidimensional 1ππ*/1nπ* conical intersection seam onto the multidimensional potential energy surface of the 1ππ* state might exist and determine the relaxation processes of aqueous thymidine upon UV excitation.

2.
Front Pharmacol ; 15: 1444169, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39234112

RESUMEN

Objectives: Olanzapine is used for treating bipolar disorder (BPD); however, the optimal initial dosing regimen is unclear. The present study aimed to investigate the optimal olanzapine initial dosage in patients with BPD via model-informed precision dosing (MIPD) based on a real-world study. Methods: Thirty-nine patients with BPD from the real-world study were collected to construct the MIPD model. Results: Weight, combined used quetiapine influenced olanzapine clearances in patients with BPD, where the clearance rates were 0.152:1 in patients with or without quetiapine under the same weight. We simulated olanzapine doses once a day or twice a day, of which twice a day was optimal. Without quetiapine, for twice-a-day olanzapine doses, 0.80, 0.70, and 0.60 mg/kg/day were suitable for 40- to 56-kg BPD patients, 56- to 74-kg BPD patients, and 74- to 100-kg BPD patients, respectively. With quetiapine, for twice-a-day olanzapine doses, 0.05 mg/kg/day was suitable for 40- to 100-kg BPD patients. Conclusion: This study was the first to investigate the optimal olanzapine initial dosage in patients with BPD via MIPD based on a real-world study, providing clinical reference for the precision medication of olanzapine in BPD patients.

3.
J Vasc Access ; : 11297298241278384, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39243114

RESUMEN

INTRODUCTION: Mirror people have difficulty with PICC placement due to inversion of organs. Intracavitary electrocardiography (IC-ECG) guided peripherally inserted central catheter (PICC) tip location technique has been widely applied in clinical practice. CASE DESCRIPTION: Herein, we admitted a 59-year-old man diagnosed with esophageal cancer (EC). Chest X-ray and computed tomography (CT) revealed that the patient was with a mirror-image dextrocardia and situs inversus totalis: the heart and stomach located in the right side of the body, whereas the liver located in the left side. Echocardiography suggested that the apex of the heart pointed toward the right, while the left and right chambers were inverted. The relationship of the heart chambers, structure, and function were normal: left ventricular ejection fraction was 0.67, left atrial diameter was 31 mm, and heart output was 4.7 L/min. Surface ECG showed typical features of a dextrocardia: P-wave inverted on lead I. Amplitude of the R-wave and S-wave decreased gradually on lead chest from V1 to V5. Compared with the normal ECG image, the waves completely exchanged on lead II and III, so as on aVR and aVL. METHODS: Column of saline technique can assist operator estimate the tip position in real-time according to P-wave changes. When the height of P-wave reaches to its highest, it means that the tip of catheter has advanced to the target position of cavo-atrial junction (CAJ). OUTCOMES: Patient was inserted catheter and no adverse events were reported. CONCLUSIONS: Measuring the predicted length of catheter is still an indispensible procedure to help precisely adjusting the tip position in IC-ECG guided PICC. Our work provides both supplement for clinical data to facilitate further research and better understanding of special types of PICC to clinicians.

4.
Int J Mol Sci ; 25(17)2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39273653

RESUMEN

Mitochondrial damage is an early and key marker of neuronal damage in prion diseases. As a process involved in mitochondrial quality control, mitochondrial biogenesis regulates mitochondrial homeostasis in neurons and promotes neuron health by increasing the number of effective mitochondria in the cytoplasm. Sirtuin 1 (SIRT1) is a NAD+-dependent deacetylase that regulates neuronal mitochondrial biogenesis and quality control in neurodegenerative diseases via deacetylation of a variety of substrates. In a cellular model of prion diseases, we found that both SIRT1 protein levels and deacetylase activity decreased, and SIRT1 overexpression and activation significantly ameliorated mitochondrial morphological damage and dysfunction caused by the neurotoxic peptide PrP106-126. Moreover, we found that mitochondrial biogenesis was impaired, and SIRT1 overexpression and activation alleviated PrP106-126-induced impairment of mitochondrial biogenesis in N2a cells. Further studies in PrP106-126-treated N2a cells revealed that SIRT1 regulates mitochondrial biogenesis through the PGC-1α-TFAM pathway. Finally, we showed that resveratrol resolved PrP106-126-induced mitochondrial dysfunction and cell apoptosis by promoting mitochondrial biogenesis through activation of the SIRT1-dependent PGC-1α/TFAM signaling pathway in N2a cells. Taken together, our findings further describe SIRT1 regulation of mitochondrial biogenesis and improve our understanding of mitochondria-related pathogenesis in prion diseases. Our findings support further investigation of SIRT1 as a potential target for therapeutic intervention of prion diseases.


Asunto(s)
Mitocondrias , Biogénesis de Organelos , Fragmentos de Péptidos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Priones , Sirtuina 1 , Sirtuina 1/metabolismo , Sirtuina 1/genética , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Priones/metabolismo , Animales , Ratones , Fragmentos de Péptidos/metabolismo , Resveratrol/farmacología , Factores de Transcripción/metabolismo , Transducción de Señal/efectos de los fármacos , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Neuronas/metabolismo , Neuronas/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética
5.
J Phys Chem Lett ; 15(37): 9431-9440, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39248415

RESUMEN

Herein, a Y-type compound (67dMeOTPA-FQ) and a T-type compound (58dMeOTPA-FQ) based on furo[2,3-b]quinoxaline were synthesized. The theory calculation shows the S1 and T1 of both compounds own a charge-transfer feature while their T2 states have a local excitation feature. The calculated kRISC(T2-S1) is one to 2 orders of magnitude larger than kRISC(T1-S1). Thus, the nonadiabatic spin-vibronic mechanism involved in the T2 state is suggested to be responsible for the thermally activated delayed fluorescence (TADF) feature. Meanwhile, when 2-methyl-9,10-bis(naphthalen-2-yl)anthracene is selected as host, the maximum luminance of the device based on 67dMeOTPA-FQ is up to 104215 cd·m-2, and the external quantum efficiency (EQE) keeps in the 8.2-8.0% range with the luminance changed from 55.0 cd·m-2 to 90000 cd·m-2, only 2.4% efficiency roll-off. As for 58dMeOTPA-FQ, a slightly lower EQE of 7.1-6.7% with the luminance range of 1-40000 cd·m-2 was achieved for orange-red emission. Both the reverse intersystem crossing (RISC) and triplet-triplet annihilation mechanisms are supposed to concurrently contribute to the utilization of triplet excitons and suppress the notorious efficiency roll-off observed in TADF-based devices.

6.
Micromachines (Basel) ; 15(9)2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39337761

RESUMEN

Due to their excellent light transmission, heat resistance, corrosion resistance, high mechanical strength, and other characteristics, transparent materials have been widely used in emerging industries such as aviation, aerospace, microelectronics, interconnected communication, etc. Compared with the traditional mechanical processing and chemical processing of transparent materials, laser processing, with such characteristics as a high peak power, high energy density, and non-contact processing, has a lot of obvious advantages in processing efficiency and accuracy. In this paper, some of the recent research advancements concerning the laser processing of transparent materials are introduced in detail. Firstly, the basic mechanism of the interaction between the laser and material is briefly summarized on the time scale. The differences in principle between nanosecond, picosecond, and femtosecond pulse laser processing are analyzed. Then, the main technical means of the nanosecond laser processing of transparent materials are summarized. Next, the main application directions of the ultrafast laser processing of transparent materials are discussed, including the preparation of optical waveguide devices, periodic structure devices, micropores, and microchannels. Finally, this paper summarizes the prospects for the future development of laser processing transparent materials.

7.
Angew Chem Int Ed Engl ; : e202414702, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39320088

RESUMEN

Aqueous Zn-metal batteries are of great interest due to their high material abundance, low production cost, and excellent safety. However, they suffer from severe side reactions and notorious dendrite growth closely related to electrolytes. Here, in-situ generated zwitterionic polymers are used as gel electrolytes to overcome these problems. It is shown that anions and H2O, but not anions and cations, are preferentially immobilized at different sites of zwitterionic polymers, facilitating the free migration of Zn2+ and reducing the side reactions. This immobilization can be associated with the dipole moment of zwitterionic polymers. As a result, poly[3-dimethyl(methacryloyl oxyethyl) ammonium propane sulfonate] (PDMAPS) stands out from a series of zwitterionic polymers and outperforms the other candidates in electrochemical performance. The symmetric cells using PDMAPS smoothly operate ~9000 h at 0.5 mA cm-2 for 0.5 mAh cm-2, much better than the controls. Moreover, PDMAPS enables an Ah-level pouch cell for continuous cycling. These results not only benefit the rational molecular design of advanced electrolytes, but also demonstrate the promising potential of zwitterionic polymers in aqueous Zn-metal batteries.

8.
Angew Chem Int Ed Engl ; : e202414117, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39315791

RESUMEN

Rechargeable aqueous Zn metal batteries (AZMBs) are attractive for stationary energy storage due to their low cost and high safety. However, their practical application is hindered by the excessive use of zinc anodes and poor high-temperature performance, caused by severe side reactions and dendritic growth issues. Here, an electrolyte design strategy is reported based on bidentate coordination of Zn2+ and solvent to tailor the solvation structure. The triethylene glycol (TEG) co-solvent with two-oxygen coordination sites is demonstrated to facilitate the formation of an anions-involved solvation shell, greatly reducing the activity of coordinated H2O molecules. The sequential reduction of OTF- anions and TEG to form an organic-inorganic bilayer SEI (hydrophobic organic layer and high ion conductivity inorganic layer), protecting Zn anodes from side reaction and dendrite growth, thus ensuring an unprecedented Zn reversibility (99.95% over 5000 cycles at 0.5 mA cm-2). More importantly, the full cells of Zn||V2O5 exhibit a record-high cumulative capacity (2552 mAh cm-2) under a lean electrolyte condition (E/C ratio = 15 µL mAh-1), a limited Zn supply (N/P ratio = 1.9) and a high areal capacity (3.0 mAh cm-2).

9.
Heliyon ; 10(18): e37361, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39309925

RESUMEN

Background: The role and molecular mechanisms of collagen type VII (COL7A1) in cholangiocarcinoma (CCA) remain unknown. Methods: We analyzed the expression of COL7A1 in CCA and its relationship with patient prognosis using bioinformatic techniques. Expression levels of COL7A1 in CCA cells and tissues were detected using reverse transcription-quantitative PCR, western blotting, and immunohistochemistry. The effects of COL7A1 expression on the proliferation, migration, and invasion of CCA cells were assessed using CCK-8, colony formation, and Transwell assays. Bioinformatics and luciferase reporter gene assays were performed to examine the binding of KLF4 to COL7A1, and cytological experiments further verified the role of KLF4 in regulating the CCA phenotype through COL7A1. Xenograft mouse models were established to investigate the effects of COL7A1 on CCA tumor growth in vivo. Results: CCA tissues exhibited higher COL7A1 expression than normal bile duct tissues. There was no significant correlation between high or low COL7A1 expression and the survival time of patients with CCA. COL7A1 knockdown inhibited CCA cell proliferation, migration, and invasion. Furthermore, COL7A1 knockdown suppressed the activation of the PI3K/AKT signaling pathway. KLF4 can bind to COL7A1 and regulate COL7A1 expression, which in turn regulates the PI3K/AKT signaling pathway and impacts the proliferation and metastasis of CCA cells. Conclusion: Our findings suggest that KLF4 regulates CCA cell proliferation, migration, and invasion via the COL7A1/PI3K/AKT axis.

10.
J Affect Disord ; 368: 770-778, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39299590

RESUMEN

The effects of high doses of folic acid (FA) during pregnancy on anxiety- and depression-like behaviors in adolescent offspring mice were determined and the potential underlying mechanisms were elucidated. Pregnant C57BL/6 mice were randomly assigned to Control (2 mg/kg in feed), high FA (20 mg/kg in feed), and ultrahigh FA (40 mg/kg in feed) groups. The physiological development of the offspring, their preweaning neurobehavioral milestones, and adolescent behaviors indicative of anxiety and depression were assessed. High doses of FA during pregnancy delayed key developmental milestones such as pinna detachment, fur appearance, and incisor eruption. Furthermore, it triggered anxiety-like behavior in the passive avoidance test and led to depression-like behavior, as reflected by reduced movement distance in the center zone and decreased shuttling frequency in the light-dark box test and open field test. Additionally, brain tissues of the offspring exhibited increased expression of the microglia marker ionized calcium-binding adaptor molecule 1 and the Nod-like receptor protein 3 inflammasome. These findings suggest that high doses of FA during pregnancy may impair physiological development and increase the susceptibility of the offspring to anxiety- and depression-like behaviors, potentially mediated through the induction of low-grade inflammation in the brain.

11.
Curr Pharm Des ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39129279

RESUMEN

OBJECTIVE: The method of administering the initial doses of tacrolimus in recipients of pediatric lung transplantation, especially in patients with low hematocrit, is not clear. The present study aims to explore whether weight, CYP3A5 genotype, and voriconazole co-administration influence tacrolimus initial dosage in recipients of pediatric lung transplantation with low hematocrit based on safety and efficacy using a simulation model. METHODS: The present study utilized the tacrolimus population pharmacokinetic model, which was employed in lung transplantation recipients with low hematocrit. RESULTS: For pediatric lung transplantation recipients not carrying CYP3A5*1 and without voriconazole, the recommended tacrolimus doses for weights of 10-13, 13-19, 19-22, 22-35, 35-38, and 38-40 kg are 0.03, 0.04, 0.05, 0.06, 0.07, and 0.08 mg/kg/day, which are split into two doses, respectively. For pediatric lung transplantation recipients carrying CYP3A5*1 and without voriconazole, the recommended tacrolimus doses for weights of 10-18, 18-30, and 30-40 kg are 0.06, 0.08, 0.11 mg/kg/day, which are split into two doses, respectively. For pediatric lung transplantation recipients not carrying CYP3A5*1 and with voriconazole, the recommended tacrolimus doses for weights of 10-20 and 20-40 kg are 0.02 and 0.03 mg/kg/day, which are split into two doses, respectively. For pediatric lung transplantation recipients carrying CYP3A5*1 and with voriconazole, the recommended tacrolimus doses for weights of 10-20, 20-33, and 33-40 kg are 0.03, 0.04, and 0.05 mg/kg/day, which are split into two doses, respectively. CONCLUSION: The present study is the first to recommend the initial dosages of tacrolimus in recipients of pediatric lung transplantation with low hematocrit using a simulation model.

12.
ACS Nano ; 18(33): 21779-21803, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39132720

RESUMEN

Aqueous zinc-ion batteries (AZIBs) are widely regarded as desirable energy storage devices due to their inherent safety and low cost. Hydrogel polymer electrolytes (HPEs) are cross-linked polymers filled with water and zinc salts. They are not only widely used in flexible batteries but also represent an ideal electrolyte candidate for addressing the issues associated with the Zn anode, including dendrite formation and side reactions. In HPEs, an abundance of hydrophilic groups can form strong hydrogen bonds with water molecules, reducing water activity and inhibiting water decomposition. At the same time, special Zn2+ transport channels can be constructed in HPEs to homogenize the Zn2+ flux and promote uniform Zn deposition. However, HPEs still face issues in practical applications, including poor ionic conductivity, low mechanical strength, poor interface stability, and narrow electrochemical stability windows. This Review discusses the issues associated with HPEs for advanced AZIBs, and the recent progresses are summarized. Finally, the Review outlines the opportunities and challenges for achieving high performance HPEs, facilitating the utilization of HPEs in AZIBs.

13.
Transl Cancer Res ; 13(7): 3217-3241, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39145093

RESUMEN

Background: Lung adenocarcinoma (LUAD) stands as the most prevalent histological subtype of lung cancer, exhibiting heterogeneity in outcomes and diverse responses to therapy. CD8 T cells are consistently present throughout all stages of tumor development and play a pivotal role within the tumor microenvironment (TME). Our objective was to investigate the expression profiles of CD8 T cell marker genes, establish a prognostic risk model based on these genes in LUAD, and explore its relationship with immunotherapy response. Methods: By leveraging the expression data and clinical records from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) cohorts, we identified 23 consensus prognostic genes. Employing ten machine-learning algorithms, we generated 101 combinations, ultimately selecting the optimal algorithm to construct an artificial intelligence-derived prognostic signature named riskScore. This selection was based on the average concordance index (C-index) across three testing cohorts. Results: RiskScore emerged as an independent risk factor for overall survival (OS), progression-free interval (PFI), disease-free interval (DFI), and disease-specific survival (DSS) in LUAD. Notably, riskScore exhibited notably superior predictive accuracy compared to traditional clinical variables. Furthermore, we observed a positive correlation between the high-risk riskScore group and tumor-promoting biological functions, lower tumor mutational burden (TMB), lower neoantigen (NEO) load, and lower microsatellite instability (MSI) scores, as well as reduced immune cell infiltration and an increased probability of immune evasion within the TME. Of significance, the immunophenoscore (IPS) score displayed significant differences among risk subgroups, and riskScore effectively stratified patients in the IMvigor210 and GSE135222 immunotherapy cohort based on their survival outcomes. Additionally, we identified potential drugs that could target specific risk subgroups. Conclusions: In summary, riskScore demonstrates its potential as a robust and promising tool for guiding clinical management and tailoring individualized treatments for LUAD patients.

14.
Drug Des Devel Ther ; 18: 3629-3641, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39161682

RESUMEN

Purpose: This study aimed to establish the 95% effective dose (ED95) of esketamine in combination with propofol for hysteroscopy and then to evaluate its efficacy and safety profile. Patients and Methods: This prospective, double-blind, randomized controlled trial consisted of two cohorts. In cohort 1, 45 women aged 18-65 years undergoing hysteroscopy were randomly assigned to either group E (esketamine + propofol) or group A (alfentanil + propofol). Dixon's up-and-down method was used to determine the ED95 of esketamine and alfentanil. In cohort 2, 86 patients were randomized to group E and group A, with the calculated ED95 dose of the study drugs used for induction. The success rate of anesthesia using the ED95% dose, along with parameters related to anesthesia induction, recovery, and adverse events were also recorded. Results: The ED95 of esketamine was 0.254 mg/kg (95% CI: 0.214-1.004), while that of alfentanil was 9.121 µg/kg (95% CI: 8.479-13.364). The anesthesia success rate was 93.0% in group E and 95.2% in group A (p = 0.664). After resuscitation, both groups achieved a 100% success rate. The induction time was significantly shorter in group E (60.0 [55.0-70.0] s) compared to group A (67.0 [61.0-79.3] s) (p = 0.006). Group E had lower rates of respiratory depression (p < 0.001), hypoxia (p = 0.006), minimum perioperative SpO2 (p = 0.010), and hypotension (p = 0.001). Esketamine had less effect on respiratory rate, heart rate, mean blood pressure, and end-tidal carbon dioxide compared to alfentanil (all p < 0.001). There were no significant differences in postoperative pain between the two groups. Conclusion: This study determined the ED 95 dose of esketamine for intravenous general anesthesia during hysteroscopy. Esketamine showed less respiratory and hemodynamic depression, as well as fewer adverse effects compared to alfentanil. Esketamine is an ideal anesthetic agent compared to alfentanil for hysteroscopic anesthesia. Trial Registration: www.chictr.org.cn, (ChiCTR2300077283); registered November 3, 2023.


Asunto(s)
Alfentanilo , Histeroscopía , Ketamina , Propofol , Humanos , Alfentanilo/administración & dosificación , Ketamina/administración & dosificación , Ketamina/efectos adversos , Método Doble Ciego , Femenino , Persona de Mediana Edad , Adulto , Estudios Prospectivos , Propofol/administración & dosificación , Propofol/efectos adversos , Propofol/farmacología , Adolescente , Adulto Joven , Anciano , Relación Dosis-Respuesta a Droga , Anestésicos Intravenosos/administración & dosificación , Anestésicos Intravenosos/efectos adversos
15.
J Transl Med ; 22(1): 780, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175050

RESUMEN

BACKGROUND: Mitochondrial tRNA (mt-tRNA) variants have been found to cause disease. Post-transcriptional queuosine (Q) modifications of mt-tRNA can promote efficient mitochondrial mRNA translation. Q modifications of mt-tRNAAsn have recently been identified. Here, the therapeutic effectiveness of queuine was investigated in cells from patients with mt-tRNAAsn variants. METHODS: Six patients (from four families) carrying mt-tRNAAsn variants were included in the study. Queuine levels were quantified by mass spectrometry. Clinical, genetic, histochemical, biochemical, and molecular analysis was performed on muscle tissues and lymphoblastoid cell lines (LCLs) from patients to investigate the pathogenicity of the novel m.5708 C > T variant. The use of queuine in mitigating mitochondrial dysfunction resulting from the mt-tRNAAsn variants was evaluated. RESULTS: The variants included the m.5701 delA, m.5708 C > T, m.5709 C > T, and m.5698 G > A variants in mt-tRNAAsn. The pathogenicity of the novel m.5708 C > T variant was confirmed, as demonstrated by a decreased steady-state level of mt-tRNAAsn, mtDNA-encoded protein levels, oxygen consumption rate (OCR), and the respiratory complex activity. Notably, the serum queuine level was significantly reduced in these patients and in vitro queuine supplementation was found to restore the reductions in mitochondrial protein activities, mitochondrial membrane potential, OCR, and increases in reactive oxygen species. CONCLUSIONS: The study not only confirmed the pathogenicity of the m.5708 C > T variant but also explored the therapeutic potential of queuine in individuals with mt-tRNAAsn variants. The recognition of the novel m.5708 C > T variant's pathogenic nature contributes to our comprehension of mitochondrial disorders. Furthermore, the results emphasize queuine supplementation as a promising approach to enhance the stability of mt-tRNAAsn and rescue mitochondrial dysfunction caused by mt-tRNAAsn variants, indicating potential implications for the development of targeted therapies for patients with mt-tRNAAsn variants.


Asunto(s)
Mitocondrias , Humanos , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Masculino , Femenino , Adulto , Persona de Mediana Edad , ADN Mitocondrial/genética , Variación Genética , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Nucleósido Q/metabolismo , ARN Mitocondrial/genética , ARN Mitocondrial/metabolismo , ARN de Transferencia de Alanina/genética , ARN de Transferencia de Alanina/metabolismo
16.
J Nat Prod ; 87(8): 2014-2020, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39142023

RESUMEN

A high throughput screen performed to identify catalytic inhibitors of the oncogenic fusion form of cAMP-dependent protein kinase A catalytic subunit alpha (J-PKAcα) found an individual fraction from an organic extract of the marine soft coral Acrozoanthus australiae as active. Bioassay-guided isolation led to the identification of a 2-amino adenine alkaloid acroamine A (1), the first secondary metabolite discovered from this genus and previously reported as a synthetic product. As a naturally occurring protein kinase inhibitor, to unambiguously assign its chemical structure using modern spectroscopic and spectrometric techniques, five N-methylated derivatives acroamines A1-A5 (2-6) were semisynthesized. Three additional brominated congeners A6-A8 (7-9) were also semisynthesized to investigate the structure-activity relationship of the nine compounds as J-PKAcα inhibitors. Compounds 1-9 were tested for J-PKAcα and wild-type PKA inhibitory activities, which were observed exclusively in acroamine A (1) and its brominated analogs (7-9) achieving moderate potency (IC50 2-50 µM) while none of the N-methylated analogs exhibited kinase inhibition.


Asunto(s)
Alcaloides , Antozoos , Proteínas Quinasas Dependientes de AMP Cíclico , Animales , Antozoos/química , Estructura Molecular , Alcaloides/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Relación Estructura-Actividad , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Adenina/farmacología , Adenina/análogos & derivados , Adenina/química , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Dominio Catalítico
17.
J Mater Chem B ; 12(36): 8902-8910, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39206758

RESUMEN

Chemodynamic therapy (CDT) is a tumor-specific intervention methodology, which is based on the upregulation of reactive oxygen species (ROS) content by triggering the Fenton or Fenton-like reaction within the tumor microenvironment (TME). However, there are still challenges in achieving high-efficiency CDT on account of both the limited intracellular hydrogen peroxide (H2O2) and delivery efficiency of Fenton metal ions. Copper-based nanotherapeutic systems have attracted extensive attention and have been widely applied in the construction of nanotherapeutic systems and multimodal synergistic therapy. Herein, we propose a strategy to synergize chemotherapy drugs that upregulate intracellular ROS content with chemodynamic therapy and construct an artemisinin-copper nanoprodrug for proof-of-concept. With the proposed biomimetic self-assembly strategy, we successfully construct an injectable nanoprodrug with suitable size distribution and high drug loading content (68.1 wt%) through the self-assembly of amphiphilic artemisinin prodrug and copper ions. After reaching the TME, both Cu2+ ions and free AH drugs can be released from AHCu nanoprodrugs. Subsequently, the disassembled Cu2+ ions are converted into Cu+ ions by consuming the intracellular GSH. The generated Cu+ ions serve as a highly efficient Fenton-like reagent for robust ROS generation from both AH and tumor-over-produced H2O2. Results show that the nanoprodrug can realize the cascade amplification of ROS generation via artemisinin delivery and subsequent in situ Fenton-like reaction and a high tumor inhibition rate of 62.48% in vivo. This work provides a promising strategy for the design and development of an efficient nanoprodrug for tumor-specific treatment.


Asunto(s)
Antineoplásicos , Artemisininas , Cobre , Profármacos , Especies Reactivas de Oxígeno , Cobre/química , Cobre/farmacología , Especies Reactivas de Oxígeno/metabolismo , Artemisininas/química , Artemisininas/farmacología , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Profármacos/química , Profármacos/farmacología , Ratones , Animales , Ensayos de Selección de Medicamentos Antitumorales , Nanopartículas/química , Proliferación Celular/efectos de los fármacos , Tamaño de la Partícula , Supervivencia Celular/efectos de los fármacos , Línea Celular Tumoral , Microambiente Tumoral/efectos de los fármacos
18.
ACS Appl Mater Interfaces ; 16(36): 47110-47123, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39189050

RESUMEN

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. Research indicates that circulating histones, as pathogenic factors, may represent a therapeutic target for sepsis. However, effectively clearing circulating histones poses a challenge due to their structural similarity to normal blood proteins, their low abundance in the bloodstream, and serious interference from other blood biomacromolecules. Here we design a dodecapeptide-based functional polymer that can selectively adsorb circulating histones from the blood. The peptide, named P1 (HNHHQLALVESY), was discovered through phage display screening and demonstrated a strong affinity for circulating histones while exhibiting negligible affinities for common proteins in the blood, such as human serum albumin (HSA), immunoglobulin G (IgG), and transferrin (TRF). Furthermore, the P1 peptide was incorporated into a functional polymer design, poly(PEGMA-co-P1), which was immobilized onto a silica gel surface through reversible addition-fragmentation chain transfer polymerization. The resulting material was characterized using solid nuclear magnetic resonance, thermogravimetric analysis, and X-ray photoelectron spectroscopy. This material demonstrated the ability to selectively and efficiently capture circulating histones from both model solutions and whole blood samples while also exhibiting satisfactory blood compatibility, good antifouling properties, and resistance to interference. Satisfactory binding affinity and efficient capture capacity toward histone were also observed for the other screened peptide P2 (QMSMDLFGSNFV)-grafted polymer, validating phage display as a reliable ligand screening strategy. These findings present an approach for the specific clearance of circulating histones and hold promise for future clinical applications in blood purification toward sepsis.


Asunto(s)
Histonas , Sepsis , Sepsis/sangre , Humanos , Histonas/química , Histonas/sangre , Péptidos/química , Adsorción , Polímeros/química , Albúmina Sérica Humana/química
19.
Bioorg Chem ; 151: 107701, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39154520

RESUMEN

Four new diterpenoid tropolones, salvirrddones A-D (1-4), and four new icetexanes, salvirrddices A-D (9-12), along with thirteen new 11,12-seco-norabietane diterpenoids, salvirrddnor A-M (14-24, 31, 32) and sixteen known compounds (5-8, 13, 25-30, 33-37), were isolated from the roots and rhizomes of Salvia castanea Diels f. tomentosa Stib. Their structures were elucidated by comprehensive spectroscopic analyses, quantum chemical calculations, and X-ray crystallography. Structurally, compounds 1-8 represent a class of rare natural products featuring a unique cyclohepta-2,4,6-trienone moiety with diterpenoid skeletons. Bioassays showed that only diterpenoid tropolones 3, 5, 6, and 7 exhibited significant activity against several human cancer cell lines with IC50 values ranging from 3.01 to 11.63 µM. Additionally, 3 was shown to inhibit Hep3B cell proliferation, block the G0/G1 phase of the cell cycle, induce mitochondrial dysfunction and oxidative stress, promote apoptosis, as well as inhibit migration and invasion in vitro. Meanwhile, 3 demonstrated anti-proliferative, pro-apoptotic, and migration-inhibitory effects in the Hep3B xenograft zebrafish model in vivo. Network pharmacological analysis and molecular docking results suggested that 3 may treat hepatocellular carcinoma (HCC) through the PI3K-Akt signaling pathway, as well as by binding PARP1 and CDK2 targets. Overall, the present results extremely expand the repertoire of diterpenoids from natural products and may provide a novel chemical scaffold for the discovery of new antitumor drugs.


Asunto(s)
Antineoplásicos Fitogénicos , Apoptosis , Proliferación Celular , Diterpenos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Salvia , Pez Cebra , Humanos , Salvia/química , Proliferación Celular/efectos de los fármacos , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Relación Estructura-Actividad , Animales , Estructura Molecular , Diterpenos/farmacología , Diterpenos/química , Diterpenos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Línea Celular Tumoral
20.
Environ Pollut ; 359: 124757, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39153537

RESUMEN

In the troposphere, ozone (O3) formation can be limited by NOx, VOCs, or both, complicating efforts to reduce O3 by controlling its precursors. This study used formaldehyde (HCHO) data and nitrogen dioxide (NO2) data from the Ozone Monitoring Instrument (OMI) to analyze O3 formation sensitivity in Fujian from 2012 to 2021. Over the past decade, an 8.7% reduction in NO2 VCDs and a 9.91% increase in HCHO VCDs were observed. Due to differences in the primary driving factors, HCHO VCDs exhibit a characteristic seasonal pattern with higher in summer and lower in winter, whereas NO2 VCDs show the opposite trend. O3 formation chemistry was accurately diagnosed by combining satellite-based data and ground-based O3 data. A new threshold value (3.3-4.6) was derived to determine the transition from VOC-limited to NOx-limited O3 formation regimes. Results showed that O3 sensitivity exhibited pronounced seasonal variations. The VOC-limited regime predominates throughout the entire Fujian region in winter, whereas it occupies only 5% of the area in summer. A VOC-limited region was found widely across Fujian on an annual average, but it decreased by 24% over 10 years. Transitional areas experienced a 19% increase. In two natural emission reduction cases (reductions during the Chinese Lunar New Year holiday and reductions in weekend traffic emissions compared to weekdays), ground-level O3 effectively captured the impacts of sensitivity changes. The impact suggests that when Fujian is in the VOC control region, a significant reduction in NOx, without effective VOC control, might lead to an O3 increase. The importance of controlling VOC emissions is highlighted in Fujian. This study enhances the understanding of O3 formation regimes in southeastern China, which is crucial for developing O3 prevention and control strategies.


Asunto(s)
Contaminantes Atmosféricos , Monitoreo del Ambiente , Ozono , Estaciones del Año , Compuestos Orgánicos Volátiles , China , Ozono/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Compuestos Orgánicos Volátiles/análisis , Dióxido de Nitrógeno/análisis , Contaminación del Aire/estadística & datos numéricos , Formaldehído/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA