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1.
J Am Chem Soc ; 146(19): 13247-13257, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38701006

RESUMEN

Horseradish peroxidase (HRP) is an enzyme that oxidizes pollutants from wastewater. A previous report indicated that peroxidases can have an enhancement in initial enzymatic activity in an aqueous solution of 0.26 M 1-ethyl-3-methylimidazolium ethyl sulfate ([EMIm][EtSO4]) at neutral pH. However, the atomistic details remain elusive. In the enzymatic landscape of HRP, compound II (Cpd II) plays a key role and involves a histidine (H42) residue. Cpd II exists as oxoferryl (2a) or hydroxoferryl (2b(FeIV)) forms, where 2a is the predominantly observed form in experimental studies. Intriguingly, the ferric 2b(FeIII) form seen in synthetic complexes has not been observed in HRP. Here, we have investigated the structure and dynamics of HRP in pure water and aqueous [EMIm][EtSO4] (0.26 M), as well as the reaction mechanism of 2a to 2b conversion using polarizable molecular dynamics (MD) simulations and quantum mechanics/molecular mechanics (QM/MM) calculations. When HRP is solvated in aq [EMIm][EtSO4], the catalytic water displaces, and H42 directly orients over the ferryl moiety, allowing a direct proton transfer (PT) with a significant energy barrier reduction. Conversely, in neat water, the reaction of 2a to 2b follows the previously reported mechanism. We further investigated the deprotonated form of H42. Analysis of the electric fields at the active site indicates that the aq [EMIm][EtSO4] medium facilitates the reaction by providing a more favorable environment compared with the system solvated in neat water. Overall, the atomic level supports the previous experimental observations and underscores the importance of favorable electric fields in the active site to promote catalysis.


Asunto(s)
Peroxidasa de Rábano Silvestre , Líquidos Iónicos , Simulación de Dinámica Molecular , Peroxidasa de Rábano Silvestre/química , Peroxidasa de Rábano Silvestre/metabolismo , Líquidos Iónicos/química , Imidazoles/química , Teoría Cuántica , Soluciones , Agua/química
2.
Int J Mol Med ; 53(6)2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38695243

RESUMEN

Numerous studies have attempted to develop biological markers for the response to radiation for broad and straightforward application in the field of radiation. Based on a public database, the present study selected several molecules involved in the DNA damage repair response, cell cycle regulation and cytokine signaling as promising candidates for low­dose radiation­sensitive markers. The HuT 78 and IM­9 cell lines were irradiated in a concentration­dependent manner, and the expression of these molecules was analyzed using western blot analysis. Notably, the activation of ataxia telangiectasia mutated (ATM), checkpoint kinase 2 (CHK2), p53 and H2A histone family member X (H2AX) significantly increased in a concentration­dependent manner, which was also observed in human peripheral blood mononuclear cells. To determine the radioprotective effects of cinobufagin, as an ATM and CHK2 activator, an in vivo model was employed using sub­lethal and lethal doses in irradiated mice. Treatment with cinobufagin increased the number of bone marrow cells in sub­lethal irradiated mice, and slightly elongated the survival of lethally irradiated mice, although the difference was not statistically significant. Therefore, KU60019, BML­277, pifithrin­α, and nutlin­3a were evaluated for their ability to modulate radiation­induced cell death. The use of BML­277 led to a decrease in radiation­induced p­CHK2 and γH2AX levels and mitigated radiation­induced apoptosis. On the whole, the present study provides a novel approach for developing drug candidates based on the profiling of biological radiation­sensitive markers. These markers hold promise for predicting radiation exposure and assessing the associated human risk.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada , Daño del ADN , Radiación Ionizante , Transducción de Señal , Daño del ADN/efectos de la radiación , Daño del ADN/efectos de los fármacos , Humanos , Animales , Transducción de Señal/efectos de los fármacos , Transducción de Señal/efectos de la radiación , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Ratones , Quinasa de Punto de Control 2/metabolismo , Quinasa de Punto de Control 2/genética , Histonas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Masculino , Imidazoles/farmacología , Protectores contra Radiación/farmacología , Línea Celular Tumoral , Relación Dosis-Respuesta en la Radiación
3.
ACS Appl Mater Interfaces ; 16(19): 24398-24409, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38712727

RESUMEN

Low-molecular weight proteins (LWPs) are important sources of biological information in biomarkers, signaling molecules, and pathology. However, the separation and analysis of LWPs in complex biological samples are challenging, mainly due to their low abundance and the complex sample pretreatment procedure. Herein, trypsin modified by poly(acrylic acid) (PAA) was encapsulated by a zeolitic imidazolate framework (ZIF-L). Mesopores were formed on the ZIF-L with the introduction of PAA. An alternative strategy for separation and pretreatment of LWPs was developed based on the prepared ZIF-L-encapsulated trypsin with adjustable pore size. The mesoporous structure of the prepared materials selectively excluded high-molecular weight proteins from the reaction system, allowing LWPs to enter the pores and react with the internal trypsin, resulting in an improved separation efficiency. The hydrophobicity of the ZIF-L simplified the digestion process by inducing significant structural changes in substrate proteins. In addition, the enzymatic activity was significantly enhanced by the developed encapsulation method that maintained the enzyme conformation, allowed low mass transfer resistance, and possessed a high enzyme-to-substrate ratio. As a result, the ZIF-L-encapsulated trypsin can achieve highly selective separation, valid denaturation, and efficient digestion of LWPs in a short time by simply mixing with substrate proteins, greatly simplifying the separation and pretreatment process of the traditional hydrolysis method. The prepared materials and the developed strategy demonstrated an excellent size-selective assay performance in model protein mixtures, showing great potential in the application of proteomics analysis.


Asunto(s)
Imidazoles , Tripsina , Zeolitas , Tripsina/química , Tripsina/metabolismo , Zeolitas/química , Imidazoles/química , Peso Molecular , Resinas Acrílicas/química , Porosidad , Proteínas/química
4.
Pak J Pharm Sci ; 37(2): 349-356, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38767102

RESUMEN

Evidence suggests that surgical procedures can effect the central nervous system and lead to changes in mood and behavior, rarely understood about the role of acute inflammation in promoting acute anxiety postoperatively. This study was designed to explore the possible mechanism of dexmedetomidine (DEX, a2-adrenergic receptor agonist) for reducing acute postoperative anxiety, which may be related to the activation of nuclear factor kappa B (NF-κB) and downstream signal pathway in the hippocampus. Experiments were conducted with rat, the elevated plus-maze and open field test were performed to evaluate anxiety-like behavior. Inhibit DEX with Atipamezole (AT, α2-adrenergic receptor antagonist) and inhibit NF-κB with Pyrrolidinedithiocarbamate (PDTC, inhibit phosphorylation of IκB, prevent the activation of NF-κB), the level of interleukin-6 (IL-6), IL-1ß, IL-10 and Tumor necrosis factor-α (TNF-α); the nuclear translocation of NF-κB in the hippocampus and anxiety-like behavior were measured. Rats exhibited anxiety-like behavior at 6h and 12h after surgery. Preoperative administration of DEX significantly alleviated postoperative anxiety-like behavior. DEX premedication inhibited the nuclear translocation of NF-κB alleviate acute postoperative anxiety. These findings are the first to show that acute postoperative anxiety may be related to NF-κB nuclear translocation in the hippocampus in rats, which can be alleviated by DEX premedication.


Asunto(s)
Ansiedad , Dexmedetomidina , Hipocampo , FN-kappa B , Ratas Sprague-Dawley , Transducción de Señal , Animales , Dexmedetomidina/farmacología , FN-kappa B/metabolismo , Masculino , Ansiedad/tratamiento farmacológico , Ansiedad/psicología , Transducción de Señal/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Ratas , Agonistas de Receptores Adrenérgicos alfa 2/farmacología , Conducta Animal/efectos de los fármacos , Ansiolíticos/farmacología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Imidazoles
5.
Anal Chim Acta ; 1309: 342701, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38772662

RESUMEN

BACKGROUND: Nanozymes, a new class of nanomaterials, have emerged as promising substitutes for enzymes in biosensor design due to their exceptional stability, affordability, and ready availability. While nanozymes address many limitations of natural enzymes, they still face challenges, particularly in achieving the catalytic activity levels of their natural counterparts. This indicates the need for enhancing the sensitivity of biosensors based on nanozymes. The catalytic activity of nanozyme can be significantly improved by regulating its size, morphology, and surface composition of nanomaterial. RESULTS: In this work, a kind of hollow core-shell structure was designed to enhance the catalytic activity of nanozymes. The hollow core-shell structure material consists of a nanozymes core layer, a hollow layer, and a MOF shell layer. Taking the classic peroxidase like Fe3O4 as an example, the development of a novel nanozyme@MOF, specifically p-Fe3O4@PDA@ZIF-67, is detailed, showcasing its application in enhancing the sensitivity of sensors based on Fe3O4 nanozymes. This innovative nanocomposite, featuring that MOF layer was designed to adsorb the signal molecules of the sensor to improve the utilization rate of reactive oxygen species generated by the nanozymes catalyzed reactions and the hollow layer was designed to prevent the active sites of nanozymes from being cover by the MOF layer. The manuscript emphasizes the nanocomposite's remarkable sensitivity in detecting hydrogen peroxide (H2O2), coupled with high specificity and reproducibility, even in complex environments like milk samples. SIGNIFICANCE AND NOVELTY: This work firstly proposed and proved that Fe3O4 nanozyme@MOF with hollow layer structure was designed to improve the catalytic activity of the Fe3O4 nanozyme and the sensitivity of the sensors based on Fe3O4 nanozyme. This research marks a significant advancement in nanozyme technology, demonstrating the potential of structural innovation in creating high-performance, sensitive, and stable biosensors for various applications.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Técnicas Biosensibles/métodos , Estructuras Metalorgánicas/química , Óxido Ferrosoférrico/química , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/análisis , Indoles/química , Catálisis , Límite de Detección , Nanoestructuras/química , Nanocompuestos/química , Imidazoles , Polímeros , Zeolitas
6.
J Assoc Physicians India ; 72(3): 75-78, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38736121

RESUMEN

For >3 decades now, angiotensin receptor blockers (ARB) have been used in the management of hypertension (HTN) and HTN-related cardiovascular (CV) diseases. Olmesartan medoxomil (OLM) is an angiotensin II type 1 (AT1) receptor antagonist (or blocker) that binds tightly to the AT1 receptor with long-lasting efficacy over the 24-hour period and safety demonstrated in several trials. It is well tolerated and effective in reducing blood pressure (BP) in mono and combination therapy with thiazide diuretics or calcium channel blockers across a wide range of patient subgroups. The effectiveness and safety of OLM-based combination therapies have good and tolerable profiles with high adherence in the fixed single-pill formulation. Consistent antihypertensive efficacy and good tolerability when used as monotherapy or as a combined therapy make OLM a valuable treatment option for adults with HTN. In this review, we discuss the important clinical implications of OLM as an optimal choice as monotherapy and combination therapy in managing patients with HTN.


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II , Antihipertensivos , Presión Sanguínea , Quimioterapia Combinada , Hipertensión , Imidazoles , Humanos , Hipertensión/tratamiento farmacológico , Antihipertensivos/uso terapéutico , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Imidazoles/uso terapéutico , Tetrazoles/uso terapéutico , Olmesartán Medoxomilo/uso terapéutico
7.
Int J Mol Sci ; 25(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38731811

RESUMEN

Recently studied N-(ß-d-glucopyranosyl)-3-aryl-1,2,4-triazole-5-carboxamides have proven to be low micromolar inhibitors of glycogen phosphorylase (GP), a validated target for the treatment of type 2 diabetes mellitus. Since in other settings, the bioisosteric replacement of the 1,2,4-triazole moiety with imidazole resulted in significantly more efficient GP inhibitors, in silico calculations using Glide molecular docking along with unbound state DFT calculations were performed on N-(ß-d-glucopyranosyl)-arylimidazole-carboxamides, revealing their potential for strong GP inhibition. The syntheses of the target compounds involved the formation of an amide bond between per-O-acetylated ß-d-glucopyranosylamine and the corresponding arylimidazole-carboxylic acids. Kinetics experiments on rabbit muscle GPb revealed low micromolar inhibitors, with the best inhibition constants (Kis) of ~3-4 µM obtained for 1- and 2-naphthyl-substituted N-(ß-d-glucopyranosyl)-imidazolecarboxamides, 2b-c. The predicted protein-ligand interactions responsible for the observed potencies are discussed and will facilitate the structure-based design of other inhibitors targeting this important therapeutic target. Meanwhile, the importance of the careful consideration of ligand tautomeric states in binding calculations is highlighted, with the usefulness of DFT calculations in this regard proposed.


Asunto(s)
Inhibidores Enzimáticos , Glucógeno Fosforilasa , Imidazoles , Simulación del Acoplamiento Molecular , Cinética , Conejos , Animales , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Glucógeno Fosforilasa/antagonistas & inhibidores , Glucógeno Fosforilasa/metabolismo , Glucógeno Fosforilasa/química , Imidazoles/química , Imidazoles/síntesis química , Imidazoles/farmacología , Simulación por Computador , Relación Estructura-Actividad , Triazoles/química , Triazoles/farmacología , Triazoles/síntesis química
8.
Cancer Immunol Immunother ; 73(7): 119, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713205

RESUMEN

BACKGROUND: The programmed death 1 inhibitor toripalimab plus the angio-immuno kinase inhibitor surufatinib showed a tolerable safety profile and preliminary efficacy in patients with advanced solid tumors in a phase I study. METHODS: This open-label, multi-cohort study in China enrolled patients with advanced solid tumors who had failed or were intolerable to standard treatment into tumor-specific cohorts. Patients received surufatinib (250 mg orally, once daily) plus toripalimab (240 mg intravenously, once every three weeks). Results for three cohorts (gastric/gastroesophageal junction [GC/GEJ] adenocarcinoma, esophageal squamous cell carcinoma [ESCC], and biliary tract carcinoma [BTC]) are reported here. The primary endpoint was investigator-assessed objective response rate (ORR) per Response Evaluation criteria in Solid Tumors version 1.1. RESULTS: Between December 17, 2019, and January 29, 2021, 60 patients were enrolled (GC/GEJ, n = 20; ESCC, n = 20; BTC, n = 20). At data cutoff (February 28, 2023), ORRs were 31.6%, 30.0%, and 11.1%, respectively. Median progression-free survival was 4.1, 2.7, and 2.9 months, respectively. Median overall survival was 13.7, 10.4, and 7.0 months, respectively. Overall, grade ≥ 3 treatment-related adverse events occurred in 28 (46.7%) patients. CONCLUSIONS: Surufatinib plus toripalimab showed promising antitumor activity and a tolerable safety profile in immunotherapy-naïve patients with GC/GEJ adenocarcinoma, ESCC, or BTC. These findings warrant further study in larger randomized trials comparing surufatinib plus toripalimab with standard therapies in these tumors. CLINICALTRIALS: gov NCT04169672.


Asunto(s)
Adenocarcinoma , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias del Sistema Biliar , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/patología , Neoplasias del Sistema Biliar/tratamiento farmacológico , Neoplasias del Sistema Biliar/patología , Neoplasias del Sistema Biliar/mortalidad , Adulto , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/patología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/mortalidad , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Unión Esofagogástrica/patología , Imidazoles/administración & dosificación , Imidazoles/uso terapéutico , Imidazoles/efectos adversos , Anciano de 80 o más Años , Estudios de Cohortes
9.
J Nanobiotechnology ; 22(1): 235, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38725031

RESUMEN

Different from most of the conventional platforms with dissatisfactory theranostic capabilities, supramolecular nanotheranostic systems have unparalleled advantages via the artful combination of supramolecular chemistry and nanotechnology. Benefiting from the tunable stimuli-responsiveness and compatible hierarchical organization, host-guest interactions have developed into the most popular mainstay for constructing supramolecular nanoplatforms. Characterized by the strong and diverse complexation property, cucurbit[8]uril (CB[8]) shows great potential as important building blocks for supramolecular theranostic systems. In this review, we summarize the recent progress of CB[8]-based supramolecular theranostics regarding the design, manufacture and theranostic mechanism. Meanwhile, the current limitations and corresponding reasonable solutions as well as the potential future development are also discussed.


Asunto(s)
Hidrocarburos Aromáticos con Puentes , Imidazoles , Nanomedicina Teranóstica , Nanomedicina Teranóstica/métodos , Hidrocarburos Aromáticos con Puentes/química , Imidazoles/química , Humanos , Animales , Nanopartículas/química , Compuestos Heterocíclicos con 2 Anillos , Compuestos Macrocíclicos , Imidazolidinas
10.
Sci Rep ; 14(1): 11388, 2024 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762672

RESUMEN

Capmatinib is a potent selective mesenchymal-epithelial transition inhibitor approved in 2020 for the treatment of metastatic non-small cell lung cancer. As real-world evidence is very limited, this study evaluated capmatinib-induced adverse events through data mining of the FDA Adverse Event Reporting System database. Four disproportionality analysis methods were employed to quantify the signals of capmatinib-related adverse events. The difference in capmatinib-associated adverse event signals was further investigated with respect to sex, age, weight, dose, onset time, continent, and concomitant drug. A total of 1518 reports and 4278 adverse events induced by capmatinib were identified. New significant adverse event signals emerged, such as dysphagia, dehydration, deafness, vocal cord paralysis, muscle disorder, and oesophageal stenosis. Notably, higher risk of alanine aminotransferase and aspartate aminotransferase increases were observed in females, especially when capmatinib was combined with immune checkpoint inhibitors. Compared with Europeans and Asians, Americans were more likely to experience peripheral swelling, especially in people > 65 years of age. Renal impairment and increased blood creatinine were more likely to occur with single doses above 400 mg and in Asians. This study improves the understanding of safety profile of capmatinib.


Asunto(s)
Sistemas de Registro de Reacción Adversa a Medicamentos , Benzamidas , Farmacovigilancia , United States Food and Drug Administration , Humanos , Masculino , Femenino , Estados Unidos , Persona de Mediana Edad , Anciano , Sistemas de Registro de Reacción Adversa a Medicamentos/estadística & datos numéricos , Benzamidas/efectos adversos , Benzamidas/uso terapéutico , Adulto , Triazinas/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Anciano de 80 o más Años , Adulto Joven , Neoplasias Pulmonares/tratamiento farmacológico , Adolescente , Imidazoles
11.
Int J Nanomedicine ; 19: 4253-4261, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38766662

RESUMEN

Purpose: Recently, Single-atom-loaded carbon-based material is a new environmentally friendly and stable photothermal antibacterial nanomaterial. It is still a great challenge to achieve single-atom loading on carbon materials. Materials and Methods: Herein, We doped single-atom Ag into ZIF-8-derived porous carbon to obtain Ag-doped ZIF-8-derived porous carbon(AgSA-ZDPC). The as-prepared samples were characterized by XRD, XPS, FESEM, EDX, TEM, and HAADF-STEM which confirmed that the single-atom Ag successfully doped into the porous carbon. Further, the photothermal properties and antimicrobial activity of AgSA-ZDPC have been tested. Results: The results showed that the temperature increased by 30 °C after near-infrared light irradiation(1 W/cm2) for 5 min which was better than ZIF-8-derived porous carbon(ZDPC). It also exhibits excellent photothermal stability after the laser was switched on and off 5 times. When the AgSA-ZDPC concentration was greater than 50 µg/mL and the near-infrared irradiation was performed for 5 min, the growth inhibition of S. aureus and E. coli was almost 100%. Conclusion: This work provides a simple method for the preparation of single-atom Ag-doped microporous carbon which has potential antibacterial application.


Asunto(s)
Antibacterianos , Carbono , Escherichia coli , Plata , Staphylococcus aureus , Antibacterianos/química , Antibacterianos/farmacología , Plata/química , Plata/farmacología , Porosidad , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Carbono/química , Carbono/farmacología , Rayos Infrarrojos , Pruebas de Sensibilidad Microbiana , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Zeolitas/química , Zeolitas/farmacología , Imidazoles
12.
J Pharm Biomed Anal ; 245: 116179, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38703749

RESUMEN

A sensitive, reproducible, robust, high-throughput ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous quantification of fexofenadine and olmesartan in human serum. Samples (50 µL) undergo protein precipitation prior to UPLC-MS/MS analysis. The analytes were separated using an Acquity BEH C18 column (2.1 mm × 50 mm, 1.7 µm) at a flow rate of 0.5 mL/min using a gradient elution with a total run time of 4 min. The analytes were detected in positive ion mode and selected reaction monitoring (SRM) was used for quantitation. The standard curve concentration range was 1.0-500.0 ng/mL for both analytes and each analyte showed excellent linearity with correlation coefficients (R2 > 0.99). The intra- and inter-day accuracy and precision were ±15% for each analyte, and excellent recovery was demonstrated (93-98%) for both analytes. The method is well suited for high-throughput quantitative determination of fexofenadine and olmesartan simultaneously and was successfully applied to an in vivo pharmacokinetic and transporter phenotyping study in humans.


Asunto(s)
Imidazoles , Espectrometría de Masas en Tándem , Terfenadina , Tetrazoles , Terfenadina/análogos & derivados , Terfenadina/farmacocinética , Terfenadina/sangre , Espectrometría de Masas en Tándem/métodos , Imidazoles/sangre , Imidazoles/farmacocinética , Humanos , Tetrazoles/sangre , Tetrazoles/farmacocinética , Cromatografía Líquida de Alta Presión/métodos , Reproducibilidad de los Resultados , Cromatografía Líquida con Espectrometría de Masas
13.
J Am Chem Soc ; 146(20): 13875-13885, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38718165

RESUMEN

Bioluminescence is a fascinating natural phenomenon, wherein organisms produce light through specific biochemical reactions. Among these organisms, Renilla luciferase (RLuc) derived from the sea pansy Renilla reniformis is notable for its blue light emission and has potential applications in bioluminescent tagging. Our study focuses on RLuc8, a variant of RLuc with eight amino acid substitutions. Recent studies have shown that the luminescent emitter coelenteramide can adopt multiple protonation states, which may be influenced by nearby residues at the enzyme's active site, demonstrating a complex interplay between protein structure and bioluminescence. Herein, using the quantum mechanical consistent force field method and the semimacroscopic protein dipole-Langevin dipole method with linear response approximation, we show that the phenolate state of coelenteramide in RLuc8 is the primary light-emitting species in agreement with experimental results. Our calculations also suggest that the proton transfer (PT) from neutral coelenteramide to Asp162 plays a crucial role in the bioluminescence process. Additionally, we reproduced the observed emission maximum for the amide anion in RLuc8-D120A and the pyrazine anion in the presence of a Na+ counterion in RLuc8-D162A, suggesting that these are the primary emitters. Furthermore, our calculations on the neutral emitter in the engineered AncFT-D160A enzyme, structurally akin to RLuc8-D162A but with a considerably blue-shifted emission peak, aligned with the observed data, possibly explaining the variance in emission peaks. Overall, this study demonstrates an effective approach to investigate chromophores' bimolecular states while incorporating the PT process in emission spectra calculations, contributing valuable insights for future studies of PT in photoproteins.


Asunto(s)
Pirazinas , Teoría Cuántica , Pirazinas/química , Pirazinas/metabolismo , Renilla/enzimología , Luciferasas/química , Luciferasas/metabolismo , Luminiscencia , Animales , Imidazoles/química , Bencenoacetamidas
14.
NPJ Syst Biol Appl ; 10(1): 51, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750040

RESUMEN

In vertical inhibition treatment strategies, multiple components of an intracellular pathway are simultaneously inhibited. Vertical inhibition of the BRAFV600E-MEK-ERK signalling pathway is a standard of care for treating BRAFV600E-mutated melanoma where two targeted cancer drugs, a BRAFV600E-inhibitor, and a MEK inhibitor, are administered in combination. Targeted therapies have been linked to early onsets of drug resistance, and thus treatment strategies of higher complexities and lower doses have been proposed as alternatives to current clinical strategies. However, finding optimal complex, low-dose treatment strategies is a challenge, as it is possible to design more treatment strategies than are feasibly testable in experimental settings. To quantitatively address this challenge, we develop a mathematical model of BRAFV600E-MEK-ERK signalling dynamics in response to combinations of the BRAFV600E-inhibitor dabrafenib (DBF), the MEK inhibitor trametinib (TMT), and the ERK-inhibitor SCH772984 (SCH). From a model of the BRAFV600E-MEK-ERK pathway, and a set of molecular-level drug-protein interactions, we extract a system of chemical reactions that is parameterised by in vitro data and converted to a system of ordinary differential equations (ODEs) using the law of mass action. The ODEs are solved numerically to produce simulations of how pathway-component concentrations change over time in response to different treatment strategies, i.e., inhibitor combinations and doses. The model can thus be used to limit the search space for effective treatment strategies that target the BRAFV600E-MEK-ERK pathway and warrant further experimental investigation. The results demonstrate that DBF and DBF-TMT-SCH therapies show marked sensitivity to BRAFV600E concentrations in silico, whilst TMT and SCH monotherapies do not.


Asunto(s)
Imidazoles , Sistema de Señalización de MAP Quinasas , Melanoma , Inhibidores de Proteínas Quinasas , Proteínas Proto-Oncogénicas B-raf , Piridonas , Pirimidinonas , Proteínas Proto-Oncogénicas B-raf/genética , Humanos , Piridonas/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/genética , Melanoma/tratamiento farmacológico , Melanoma/genética , Imidazoles/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinonas/farmacología , Oximas/farmacología , Simulación por Computador , Modelos Biológicos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Mutación , Antineoplásicos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética
15.
ACS Appl Bio Mater ; 7(5): 3375-3387, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38693867

RESUMEN

Encapsulation of natural polymer pectin (Pec) into a zeolitic imidazolate framework-12 (ZIF-12) matrix via a simple chemical method toward anticancer agent gallic acid (GA) detection is reported in this work. GA, a natural phenol found in many food sources, has gained attention by its biological effects on the human body, such as an antioxidant and anti-inflammatory. Therefore, it is crucial to accurately and rapidly determine the GA level in humans. The encapsulation of Pec inside the ZIF-12 has been successfully confirmed from the physiochemical studies such as XRD, Raman, FTIR, and XPS spectroscopy along with morphological FESEM, BET, and HRTEM characterization. Under optimized conditions, the Pec@ZIF-12 composite exhibits wide linear range of 20 nM-250 µM with a detection limit of 2.2 nM; also, it showed excellent selectivity, stability, and reproducibility. Furthermore, the real sample analysis of food samples including tea, coffee, grape, and pomegranate samples shows exceptional recovery percentage in an unspiked manner. So far, there is little literature for encapsulating proteins, enzymes, metals, etc., that have been reported; here, we successfully encapsulated a natural polymer Pec inside the ZIF-12 cage. This encapsulation significantly enhanced the composite electrochemical performance, which could be seen from the overall results. All of these strongly suggest that the proposed Pec@ZIF-12 composite could be used for miniaturized device fabrication for the evaluation of GA in both home and industrial applications.


Asunto(s)
Antineoplásicos , Técnicas Electroquímicas , Imidazoles , Zeolitas , Zeolitas/química , Antineoplásicos/química , Antineoplásicos/farmacología , Imidazoles/química , Ensayo de Materiales , Ácido Gálico/química , Tamaño de la Partícula , Materiales Biocompatibles/química , Polímeros/química , Pectinas/química , Estructuras Metalorgánicas/química , Humanos
16.
J Appl Oral Sci ; 32: e20230447, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38695448

RESUMEN

OBJECTIVE: To evaluate whether antimicrobial photodynamic therapy (aPDT) repairs bisphosphonate-related osteonecrosis of the jaw (BRONJ) modulated by the reduction of NF-kB protein in a murine model. METHODOLOGY: Male Wistar rats (N=30) were divided into the following groups (n=6/group): negative control (NC); experimental osteonecrosis (ONE); ONE + photosensitizer (PS); ONE + photobiomodulation (PBM); and ONE + aPDT. Over 8 weeks, ONE was induced by zoledronic acid 250 µg/kg injections, except in the NC group, which received sterile 0.9% saline, followed by extraction of the lower left first molar. Red light laser irradiation (wavelength ~660 nm, power 50 mW, energy of 2 J, energy dose of 66.67 J/cm2 for 40 s) was performed once a week for 4 weeks. Methylene blue 0.3% was used as PS. The animals were euthanized and examined macroscopically for the presence of exposed bone and epithelial repair and microscopically by histochemical (hematoxylin-eosin and Masson's trichrome staining) and immunohistochemical (anti-NF-kB) methods. Macroscopic and histomorphometric data were analyzed by one-way ANOVA and Tukey's post-test (p<0.05). RESULTS: Mucosal repair, viable osteocytes, and NF-kB immunostaining were observed in the NC, ONE+PS, ONE+PBM, and ONE+aPDT groups. The ONE group showed no mucosal repair, showing empty lacunae and multifocal immunostaining for NF-kB. The ONE+PBM and ONE+aPDT groups had greater deposition of extracellular matrix and less necrotic bone tissue (p<0.05). CONCLUSION: PBM and aPDT treatments for BRONJ were effective for bone and epithelial repair, in addition to reducing inflammation mediated by the decrease of NF-kB protein in the irradiated regions.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos , Modelos Animales de Enfermedad , Inmunohistoquímica , FN-kappa B , Fotoquimioterapia , Fármacos Fotosensibilizantes , Ratas Wistar , Animales , Masculino , Fotoquimioterapia/métodos , Osteonecrosis de los Maxilares Asociada a Difosfonatos/patología , FN-kappa B/análisis , Fármacos Fotosensibilizantes/farmacología , Factores de Tiempo , Reproducibilidad de los Resultados , Ácido Zoledrónico/farmacología , Resultado del Tratamiento , Imidazoles/farmacología , Difosfonatos/farmacología , Terapia por Luz de Baja Intensidad/métodos , Azul de Metileno/farmacología , Azul de Metileno/uso terapéutico , Análisis de Varianza , Distribución Aleatoria , Conservadores de la Densidad Ósea/farmacología
17.
Nat Commun ; 15(1): 3882, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719809

RESUMEN

In this randomized phase II clinical trial, we evaluated the effectiveness of adding the TLR agonists, poly-ICLC or resiquimod, to autologous tumor lysate-pulsed dendritic cell (ATL-DC) vaccination in patients with newly-diagnosed or recurrent WHO Grade III-IV malignant gliomas. The primary endpoints were to assess the most effective combination of vaccine and adjuvant in order to enhance the immune potency, along with safety. The combination of ATL-DC vaccination and TLR agonist was safe and found to enhance systemic immune responses, as indicated by increased interferon gene expression and changes in immune cell activation. Specifically, PD-1 expression increases on CD4+ T-cells, while CD38 and CD39 expression are reduced on CD8+ T cells, alongside an increase in monocytes. Poly-ICLC treatment amplifies the induction of interferon-induced genes in monocytes and T lymphocytes. Patients that exhibit higher interferon response gene expression demonstrate prolonged survival and delayed disease progression. These findings suggest that combining ATL-DC with poly-ICLC can induce a polarized interferon response in circulating monocytes and CD8+ T cells, which may represent an important blood biomarker for immunotherapy in this patient population.Trial Registration: ClinicalTrials.gov Identifier: NCT01204684.


Asunto(s)
Linfocitos T CD8-positivos , Vacunas contra el Cáncer , Carboximetilcelulosa de Sodio/análogos & derivados , Células Dendríticas , Glioma , Interferones , Poli I-C , Polilisina/análogos & derivados , Humanos , Células Dendríticas/inmunología , Células Dendríticas/efectos de los fármacos , Glioma/inmunología , Glioma/terapia , Femenino , Masculino , Persona de Mediana Edad , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/administración & dosificación , Vacunas contra el Cáncer/uso terapéutico , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/efectos de los fármacos , Poli I-C/administración & dosificación , Poli I-C/farmacología , Adulto , Receptores Toll-Like/agonistas , Imidazoles/farmacología , Imidazoles/uso terapéutico , Anciano , Vacunación , Monocitos/inmunología , Monocitos/efectos de los fármacos , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/tratamiento farmacológico , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/efectos de los fármacos , Inmunoterapia/métodos , Agonistas de los Receptores Toll-Like
18.
BMJ Case Rep ; 17(5)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719253

RESUMEN

The combination therapy of v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) and mitogen-activated protein kinase kinase (MEK) inhibitors is approved for treating patients with BRAF V600E-positive tumours, including melanoma and lung cancer. Several case reports indicated autoimmune side effects associated with the use of BRAF and MEK inhibitors. Still, the effects of these drugs on the immune system were not fully elucidated. Here, we report a patient with large-vessel vasculitis diagnosed after initiation of treatment with dabrafenib and trametinib for BRAF V600E-positive metastatic lung adenocarcinoma. She was a never-smoker woman in her early 70s who presented with a chronic cough and was diagnosed with BRAF V600E-positive metastatic lung adenocarcinoma by transbronchial lung biopsy. She was successfully treated with prednisolone and methotrexate while BRAF and MEK inhibitors were continued. We should be careful about autoimmune diseases using BRAF and MEK inhibitors.


Asunto(s)
Adenocarcinoma del Pulmón , Imidazoles , Neoplasias Pulmonares , Oximas , Inhibidores de Proteínas Quinasas , Proteínas Proto-Oncogénicas B-raf , Piridonas , Pirimidinonas , Vasculitis , Humanos , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas B-raf/genética , Femenino , Piridonas/efectos adversos , Piridonas/uso terapéutico , Pirimidinonas/uso terapéutico , Pirimidinonas/efectos adversos , Neoplasias Pulmonares/tratamiento farmacológico , Anciano , Adenocarcinoma del Pulmón/tratamiento farmacológico , Imidazoles/efectos adversos , Imidazoles/uso terapéutico , Oximas/efectos adversos , Oximas/uso terapéutico , Vasculitis/inducido químicamente , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/uso terapéutico , Prednisolona/uso terapéutico , Metotrexato/uso terapéutico , Metotrexato/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
19.
BMJ Case Rep ; 17(5)2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38719261

RESUMEN

Olmesartan is an angiotensin II receptor blocker licensed for the treatment of hypertension. It can cause a sprue-like enteropathy (SLE), characterised by chronic diarrhoea, weight loss and villous atrophy. Transiently raised anti-tissue transglutaminase (ATTG) antibody has also been rarely reported in the literature.We describe the case of a woman in her mid-50s, who presented with a history of intermittent loose stools over 1 year, associated with significant weight loss. She had two marginally raised serum ATTG antibody tests during her work-up.After extensive investigations, she was diagnosed with olmesartan-induced enteropathy. On subsequent follow-up, her symptoms had resolved with cessation of her olmesartan therapy.This case adds to existing literature, highlighting the importance of considering olmesartan as a possible differential diagnosis for SLE. It also reports the presence of a raised ATTG antibody which is infrequently reported in this context.


Asunto(s)
Diarrea , Imidazoles , Tetrazoles , Transglutaminasas , Pérdida de Peso , Humanos , Femenino , Imidazoles/efectos adversos , Diarrea/inducido químicamente , Tetrazoles/efectos adversos , Persona de Mediana Edad , Transglutaminasas/inmunología , Diagnóstico Diferencial , Bloqueadores del Receptor Tipo 1 de Angiotensina II/efectos adversos , Autoanticuerpos/sangre , Proteína Glutamina Gamma Glutamiltransferasa 2 , Enfermedad Crónica , Enfermedad Celíaca/diagnóstico , Proteínas de Unión al GTP/inmunología , Proteínas de Unión al GTP/antagonistas & inhibidores
20.
Sci Rep ; 14(1): 9983, 2024 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693143

RESUMEN

The need for tumor postoperative treatments aimed at recurrence prevention and tissue regeneration have raised wide considerations in the context of the design and functionalization of implants. Herein, an injectable hydrogel system encapsulated with anti-tumor, anti-oxidant dual functional nanoparticles has been developed in order to prevent tumor relapse after surgery and promote wound repair. The utilization of biocompatible gelatin methacryloyl (GelMA) was geared towards localized therapeutic intervention. Zeolitic imidazolate framework-8@ceric oxide (ZIF-8@CeO2, ZC) nanoparticles (NPs) were purposefully devised for their proficiency as reactive oxygen species (ROS) scavengers. Furthermore, injectable GelMA hydrogels loaded with ZC NPs carrying doxorubicin (ZC-DOX@GEL) were tailored as multifunctional postoperative implants, ensuring the efficacious eradication of residual tumor cells and alleviation of oxidative stress. In vitro and in vivo experiments were conducted to substantiate the efficacy in cancer cell elimination and the prevention of tumor recurrence through the synergistic chemotherapy approach employed with ZC-DOX@GEL. The acceleration of tissue regeneration and in vitro ROS scavenging attributes of ZC@GEL were corroborated using rat models of wound healing. The results underscore the potential of the multifaceted hydrogels presented herein for their promising application in tumor postoperative treatments.


Asunto(s)
Doxorrubicina , Hidrogeles , Estructuras Metalorgánicas , Metacrilatos , Nanopartículas , Cicatrización de Heridas , Animales , Doxorrubicina/farmacología , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Cicatrización de Heridas/efectos de los fármacos , Nanopartículas/química , Hidrogeles/química , Ratas , Humanos , Especies Reactivas de Oxígeno/metabolismo , Gelatina/química , Cerio/química , Cerio/farmacología , Zeolitas/química , Zeolitas/farmacología , Línea Celular Tumoral , Masculino , Imidazoles/química , Imidazoles/administración & dosificación , Imidazoles/farmacología , Ratas Sprague-Dawley
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