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1.
Proc Natl Acad Sci U S A ; 121(6): e2309096120, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38285934

RESUMEN

Invisibility, a fascinating ability of hiding objects within environments, has attracted broad interest for a long time. However, current invisibility technologies are still restricted to stationary environments and narrow band. Here, we experimentally demonstrate a Chimera metasurface for multiterrain invisibility by synthesizing the natural camouflage traits of various poikilotherms. The metasurface achieves chameleon-like broadband in situ tunable microwave reflection mimicry of realistic water surface, shoal, beach/desert, grassland, and frozen ground from 8 to 12 GHz freely via the circuit-topology-transited mode evolution, while remaining optically transparent as an invisible glass frog. Additionally, the mechanic-driven Chimera metasurface without active electrothermal effect, owning a bearded dragon-like thermal acclimation, can decrease the maximum thermal imaging difference to 3.1 °C in tested realistic terrains, which cannot be recognized by human eyes. Our work transitions camouflage technologies from the constrained scenario to ever-changing terrains and constitutes a big advance toward the new-generation reconfigurable electromagnetics with circuit-topology dynamics.

2.
Mol Cell ; 72(4): 650-660.e8, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30392930

RESUMEN

DNA replication is initiated by assembly of the kinase cell division cycle 7 (CDC7) with its regulatory activation subunit, activator of S-phase kinase (ASK), to activate DNA helicase. However, the mechanism underlying regulation of CDC7-ASK complex is unclear. Here, we show that ADP generated from CDC7-mediated MCM phosphorylation binds to an allosteric region of CDC7, disrupts CDC7-ASK interaction, and inhibits CDC7-ASK activity in a feedback way. EGFR- and ERK-activated casein kinase 2α (CK2α) phosphorylates nuclear phosphoglycerate kinase (PGK) 1 at S256, resulting in interaction of PGK1 with CDC7. CDC7-bound PGK1 converts ADP to ATP, thereby abrogating the inhibitory effect of ADP on CDC7-ASK activity, promoting the recruitment of DNA helicase to replication origins, DNA replication, cell proliferation, and brain tumorigenesis. These findings reveal an instrumental self-regulatory mechanism of CDC7-ASK activity by its kinase reaction product ADP and a nonglycolytic role for PGK1 in abrogating this negative feedback in promoting tumor development.


Asunto(s)
Adenosina Difosfato/metabolismo , Quinasa de la Caseína II/metabolismo , Proteínas de Ciclo Celular/antagonistas & inhibidores , Replicación del ADN , Fosfoglicerato Quinasa/metabolismo , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Animales , Quinasa de la Caseína II/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/fisiología , Línea Celular , Línea Celular Tumoral , ADN Helicasas/genética , ADN Helicasas/metabolismo , Femenino , Xenoinjertos , Humanos , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fosfoglicerato Quinasa/genética , Fosforilación , Unión Proteica , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/fisiología , Origen de Réplica
3.
Mol Cell ; 70(3): 502-515.e8, 2018 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-29727620

RESUMEN

Nutrients are not only organic compounds fueling bioenergetics and biosynthesis, but also key chemical signals controlling growth and metabolism. Nutrients enormously impact the production of reactive oxygen species (ROS), which play essential roles in normal physiology and diseases. How nutrient signaling is integrated with redox regulation is an interesting, but not fully understood, question. Herein, we report that superoxide dismutase 1 (SOD1) is a conserved component of the mechanistic target of rapamycin complex 1 (mTORC1) nutrient signaling. mTORC1 regulates SOD1 activity through reversible phosphorylation at S39 in yeast and T40 in humans in response to nutrients, which moderates ROS level and prevents oxidative DNA damage. We further show that SOD1 activation enhances cancer cell survival and tumor formation in the ischemic tumor microenvironment and protects against the chemotherapeutic agent cisplatin. Collectively, these findings identify a conserved mechanism by which eukaryotes dynamically regulate redox homeostasis in response to changing nutrient conditions.


Asunto(s)
Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Nutrientes/metabolismo , Fosforilación/fisiología , Superóxido Dismutasa-1/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Daño del ADN/fisiología , Metabolismo Energético/fisiología , Femenino , Células HEK293 , Humanos , Células MCF-7 , Ratones Endogámicos BALB C , Ratones Desnudos , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/metabolismo
4.
Mol Cell ; 66(5): 684-697.e9, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28552616

RESUMEN

Overcoming metabolic stress is a critical step in tumor growth. Acetyl coenzyme A (acetyl-CoA) generated from glucose and acetate uptake is important for histone acetylation and gene expression. However, how acetyl-CoA is produced under nutritional stress is unclear. We demonstrate here that glucose deprivation results in AMP-activated protein kinase (AMPK)-mediated acetyl-CoA synthetase 2 (ACSS2) phosphorylation at S659, which exposed the nuclear localization signal of ACSS2 for importin α5 binding and nuclear translocation. In the nucleus, ACSS2 binds to transcription factor EB and translocates to lysosomal and autophagy gene promoter regions, where ACSS2 incorporates acetate generated from histone acetylation turnover to locally produce acetyl-CoA for histone H3 acetylation in these regions and promote lysosomal biogenesis, autophagy, cell survival, and brain tumorigenesis. In addition, ACSS2 S659 phosphorylation positively correlates with AMPK activity in glioma specimens and grades of glioma malignancy. These results underscore the significance of nuclear ACSS2-mediated histone acetylation in maintaining cell homeostasis and tumor development.


Asunto(s)
Acetato CoA Ligasa/metabolismo , Autofagia , Neoplasias Encefálicas/enzimología , Núcleo Celular/enzimología , Glioblastoma/enzimología , Histonas/metabolismo , Lisosomas/metabolismo , Biogénesis de Organelos , Transcripción Genética , Proteínas Quinasas Activadas por AMP/metabolismo , Acetato CoA Ligasa/genética , Acetilcoenzima A/metabolismo , Acetilación , Transporte Activo de Núcleo Celular , Animales , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/genética , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Sitios de Unión , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Núcleo Celular/patología , Supervivencia Celular , Metabolismo Energético , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Glioblastoma/patología , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Fosforilación , Regiones Promotoras Genéticas , Unión Proteica , Procesamiento Proteico-Postraduccional , Interferencia de ARN , Estrés Fisiológico , Transfección , alfa Carioferinas/genética , alfa Carioferinas/metabolismo
5.
J Proteome Res ; 23(7): 2376-2385, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38856018

RESUMEN

Schizophrenia is a severe psychological disorder. The current diagnosis mainly relies on clinical symptoms and lacks laboratory evidence, which makes it very difficult to make an accurate diagnosis especially at an early stage. Plasma protein profiles of schizophrenia patients were obtained and compared with healthy controls using 4D-DIA proteomics technology. Furthermore, 79 DEPs were identified between schizophrenia and healthy controls. GO functional analysis indicated that DEPs were predominantly associated with responses to toxic substances and platelet aggregation, suggesting the presence of metabolic and immune dysregulation in patients with schizophrenia. KEGG pathway enrichment analysis revealed that DEPs were primarily enriched in the chemokine signaling pathway and cytokine receptor interactions. A diagnostic model was ultimately established, comprising three proteins, namely, PFN1, GAPDH and ACTBL2. This model demonstrated an AUC value of 0.972, indicating its effectiveness in accurately identifying schizophrenia. PFN1, GAPDH and ACTBL2 exhibit potential as biomarkers for the early detection of schizophrenia. The findings of our studies provide novel insights into the laboratory-based diagnosis of schizophrenia.


Asunto(s)
Biomarcadores , Profilinas , Proteómica , Esquizofrenia , Esquizofrenia/metabolismo , Esquizofrenia/diagnóstico , Esquizofrenia/sangre , Humanos , Biomarcadores/sangre , Biomarcadores/metabolismo , Proteómica/métodos , Profilinas/metabolismo , Femenino , Masculino , Adulto , Estudios de Casos y Controles , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/metabolismo , Persona de Mediana Edad , Proteínas Sanguíneas/análisis , Proteoma/análisis
6.
J Am Chem Soc ; 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38597345

RESUMEN

Deubiquitinase-targeting chimeras (DUBTACs) have been recently developed to stabilize proteins of interest, which is in contrast to targeted protein degradation (TPD) approaches that degrade disease-causing proteins. However, to date, only the OTUB1 deubiquitinase has been utilized to develop DUBTACs via an OTUB1 covalent ligand, which could unexpectedly compromise the endogenous function of OTUB1 owing to its covalent nature. Here, we show for the first time that deubiquitinase USP7 can be harnessed for DUBTAC development. Based on a noncovalent ligand of USP7, we developed USP7-based DUBTACs that stabilized the ΔF508-CFTR mutant protein as effectively as the previously reported OTUB1-based DUBTAC. Importantly, using two different noncovalent ligands of USP7, we developed the first AMPK DUBTACs that appear to selectively stabilize different isoforms of AMPKß, leading to elevated AMPK signaling. Overall, these results highlight that, in addition to OTUB1, USP7 can be leveraged to develop DUBTACs, thus significantly expanding the limited toolbox for targeted protein stabilization and the development of novel AMPK DUBTACs as potential therapeutics.

7.
Chemistry ; 30(10): e202303832, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38085495

RESUMEN

A novel method to prepare asymmetric amine ethers is reported. Tertiary amine alcohol hydrogen sulfate intermediates are prepared through a reactive distillation process, followed by the transesterification process to afford eventually asymmetric amine ethers. Experiments and DFT calculations revealed the essential roles the sulfate group plays in the highly selective monoesterification process. This clean method is tolerant towards various functional groups with good yields under mild condition, which is obviously superior compared to the conventional processes.

8.
J Phys Chem A ; 128(4): 792-798, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38239066

RESUMEN

Gas-phase reactions of [OsC2]+ and [IrC2]+ with methane at ambient temperature have been studied using quadrupole-ion trap mass spectrometry combined with quantum chemical calculations. Both [OsC2]+ and [IrC2]+ undergo carbon-atom exchange reactions with methane. The associated mechanisms for the two systems are found to be similar. The differences in the rates of carbon isotope exchange reactions of methane with [MC2]+ (M = Os and Ir) are explained by several factors like the energy barrier for the initial H3C-H bond breaking processes, the molecular dynamics, orbital interactions, and the H-binding energies of the pivotal steps. Besides, the number of participating valence orbitals might be one of the keys to regulate the rate in the key step. The present findings may provide useful ideas and inspiration for designing similar processes.

9.
Cereb Cortex ; 33(6): 3043-3052, 2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35788284

RESUMEN

Electroencephalogram (EEG)-based brain-machine interface (BMI) has the potential to enhance rehabilitation training efficiency, but it still remains elusive regarding how to design BMI training for heterogeneous stroke patients with varied neural reorganization. Here, we hypothesize that tailoring BMI training according to different patterns of neural reorganization can contribute to a personalized rehabilitation trajectory. Thirteen stroke patients were recruited in a 2-week personalized BMI training experiment. Clinical and behavioral measurements, as well as cortical and muscular activities, were assessed before and after training. Following treatment, significant improvements were found in motor function assessment. Three types of brain activation patterns were identified during BMI tasks, namely, bilateral widespread activation, ipsilesional focusing activation, and contralesional recruitment activation. Patients with either ipsilesional dominance or contralesional dominance can achieve recovery through personalized BMI training. Results indicate that personalized BMI training tends to connect the potentially reorganized brain areas with event-contingent proprioceptive feedback. It can also be inferred that personalization plays an important role in establishing the sensorimotor loop in BMI training. With further understanding of neural rehabilitation mechanisms, personalized treatment strategy is a promising way to improve the rehabilitation efficacy and promote the clinical use of rehabilitation robots and other neurotechnologies.


Asunto(s)
Interfaces Cerebro-Computador , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Rehabilitación de Accidente Cerebrovascular/métodos , Medicina de Precisión , Accidente Cerebrovascular/terapia , Encéfalo
10.
Molecules ; 29(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38792214

RESUMEN

BACKGROUND: Staphylococcus aureus is a common pathogenic microorganism in humans and animals. Type II NADH oxidoreductase (NDH-2) is the only NADH:quinone oxidoreductase present in this organism and represents a promising target for the development of anti-staphylococcal drugs. Recently, myricetin, a natural flavonoid from vegetables and fruits, was found to be a potential inhibitor of NDH-2 of S. aureus. The objective of this study was to evaluate the inhibitory properties of myricetin against NDH-2 and its impact on the growth and expression of virulence factors in S. aureus. RESULTS: A screening method was established to identify effective inhibitors of NDH-2, based on heterologously expressed S. aureus NDH-2. Myricetin was found to be an effective inhibitor of NDH-2 with a half maximal inhibitory concentration (IC50) of 2 µM. In silico predictions and enzyme inhibition kinetics further characterized myricetin as a competitive inhibitor of NDH-2 with respect to the substrate menadione (MK). The minimum inhibitory concentrations (MICs) of myricetin against S. aureus strains ranged from 64 to 128 µg/mL. Time-kill assays showed that myricetin was a bactericidal agent against S. aureus. In line with being a competitive inhibitor of the NDH-2 substrate MK, the anti-staphylococcal activity of myricetin was antagonized by MK-4. In addition, myricetin was found to inhibit the gene expression of enterotoxin SeA and reduce the hemolytic activity induced by S. aureus culture on rabbit erythrocytes in a dose-dependent manner. CONCLUSIONS: Myricetin was newly discovered to be a competitive inhibitor of S. aureus NDH-2 in relation to the substrate MK. This discovery offers a fresh perspective on the anti-staphylococcal activity of myricetin.


Asunto(s)
Flavonoides , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus , Flavonoides/farmacología , Flavonoides/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/enzimología , Antibacterianos/farmacología , Antibacterianos/química , NADH Deshidrogenasa/antagonistas & inhibidores , NADH Deshidrogenasa/metabolismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Animales , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Humanos , Factores de Virulencia/antagonistas & inhibidores , Factores de Virulencia/metabolismo
11.
Immunol Cell Biol ; 101(3): 204-215, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36630591

RESUMEN

There is growing evidence that programmed death ligand-1 (PD-L1) has exciting therapeutic efficacy in hematological malignancy and partial solid tumors. However, many patients still face failure with the treatment of immune checkpoint blockade because of PD-L1 expression regulation during transcription and post-transcription processes, including N6-methyladenosine (m6A). Similar to the epigenetic regulation in DNA and histones, recent research has revealed the essential regulation of m6A modification in RNA nuclear export, metabolism and translation. Recent studies have shown that m6A-induced PD-L1 expression emerges as one of the main reasons for the immunological alteration in this process and contributes to the failure of T cell-induced anti-tumor immunity. The results of preclinical studies demonstrate the potential of m6A-targeted therapy in combination with immune checkpoint blockade. The comprehensive expression of m6A-related genes also provided the possibility to indicate the prognosis and to optimize the treatment for patients of various cancer types. In this review, we focus on the m6A modification in PD-L1 mRNA as well as the regulation of PD-L1 expression in cancer cells and summarize its clinical value in anti-PD-L1 cancer immune therapy.


Asunto(s)
Epigénesis Genética , Inhibidores de Puntos de Control Inmunológico , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Histonas , Adenosina
12.
Chemphyschem ; 24(11): e202200949, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36815463

RESUMEN

The performance of heteronuclear clusters [AlXO3 ]+ (X=Al, AlO4 , AlMg2 O2 , AlZnO, AlAu2 , Mg, Y, VO, NbO, TaO) in activating methane has been explored by a combination of high-level quantum calculations with reported and supplementary gas-phase experiments. With different dopants in [AlXO3 ]+ , the mechanism, reactivity and selectivity towards methane activation varies accordingly. The classic HAT competes with PCET, depending on the composition of intramolecular interactions. Although the existence of terminal oxygen radical is beneficial for classic HAT, the Alt -C interaction in the [AlXO3 ]+ clusters as enhanced by the strongly electronegative doping groups (X=Al, AlZnO, Mg, Zn, VO, NbO, TaO) favors the PCET process, facilitating C-H bond breaking. In addition, with different dopants, the destiny of the split methyl group varies accordingly. While strong interaction between Alt and CH3 results in the formation of the Alt -C bond, dopants with variable valance may promote the formation of deep-oxidation products like formaldehyde. It has been discussed in detail how to regulate the activity and selectivity of the active center of the catalyst via rational doping.

13.
Chemphyschem ; 24(24): e202300603, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-37814927

RESUMEN

The performance of heteronuclear cluster [AlFeO3 ]+ in activating methane has been explored by a combination of high-level quantum chemical calculations with gas-phase experiments. At room temperature, [AlFeO3 ]+ is a mixture of 7 [AlFeO3 ]+ and 5 [AlFeO3 ]+ , in which two states lead to different reactivity and chemoselectivity for methane activation. While hydrogen extracted from methane is the only product channel for the 7 [AlFeO3 ]+ /CH4 couple, 5 [AlFeO3 ]+ is able to convert this substrate to formaldehyde. In addition, the introduction of an external electric field may regulate the reactivity and product selectivity. The interesting doping effect of Fe and the associated electronic origins are discussed, which may guide one on the design of Fe-involved catalyst for methane conversion.

14.
Phys Chem Chem Phys ; 25(36): 24287-24292, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37665250

RESUMEN

Gas-phase reactions of [MC]+ (M = Os and Ru) with methane at ambient temperature have been studied by using quadrupole-ion trap (Q-IT) mass spectrometry combined with quantum chemical calculations. Theoretical calculations reveal the influence of electronic signatures and that it is the energy gap of the associated frontier molecular orbitals that dominates the ability of the cluster in the initial H3C-H bond breaking. By extension, a theoretical consideration upon changing the ligand from carbide to carbyne and eventually to carbene reveals that the reactivities of the M-complex (M = Os, Ru and Fe) are determined by the energy gap of the involved orbitals. In addition, a few factors like the dipole moment, spin density and charge distributions influence the orbital energy gap to different extents. Thus, altering the local structure of the active center to modulate the orbital distribution may be a possible means of regulation of the activity.

15.
Clin Lab ; 69(9)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37702668

RESUMEN

BACKGROUND: We aimed to analyze the infection characteristics of multidrug-resistant organisms (MDROs) and their resistance to antibiotics in patients with diabetic foot and provide guidance for the use of antibiotics in clinical practice. METHODS: The clinical data of 737 patients with diabetic foot who were hospitalized at our institution from February 2020 to January 2023 were retrospectively analyzed. Purulent secretions were collected from the patient's ulcers and bacterial culture, identification, and drug susceptibility tests were performed. The multidrug resistance (MDR) rate of different bacteria, composition ratio of MDROs, drug resistance characteristics of the main MDROs, distribution characteristics of multidrug-resistant gram-positive cocci and gram-negative bacilli in patients with different Wagner Grades, MDR in patients with different Wagner Grades, bacterial infection rate, and other indicators were analyzed. RESULTS: Pathogenic bacteria from wound secretions of 505 patients were cultured, and 509 pathogenic bacteria were obtained. Among the pathogenic bacteria, 225 strains were gram-positive cocci, of which 172 (76.44%) were MDROs, and 284 were gram-negative bacilli, of which 232 (81.69%) were MDROs. Among the 404 multidrug-resistant strains, gram-positive cocci and gram-negative bacilli accounted for 42.57% and 57.43%, respectively. The top five dominant MDROs were Staphylococcus aureus (18.56%), coagulase-negative Staphylococcus (10.89%), Escherichia coli (10.15%), Proteus mirabilis (8.17%), Proteus vulgaris (6.19%), and Pseudomonas aeruginosa (6.19%). Staphylococcus aureus and coagulase-negative Staphylococcus were more resistant to penicillin, oxacillin, erythromycin, azithromycin, and clarithromycin, with resistance rates of 50.0 - 95.0%. The resistance rates of E. coli to ampicillin, cefazolin, cefuroxime, ceftriaxone, and cefepime were > 75%. With an increase in Wagner Grade, the proportion of gram-negative bacilli among the pathogenic bacteria of MDROs increased significantly (p < 0.05), as did the infection rate of MDROs in patients with diabetic foot (χ2 = 14.045, p < 0.05). CONCLUSIONS: MDROs in patients with diabetic foot are mainly gram-negative bacilli, followed by gram-positive cocci. The drug resistance of various MDROs varies greatly. With the increase in Wagner Grade and MDR of diabetic foot patients, the infection rate of drug-resistant bacteria has increased significantly. Therefore, clinicians should use drugs rationally according to drug sensitivity results.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Infecciones Estafilocócicas , Humanos , Farmacorresistencia Bacteriana Múltiple , Pie Diabético/tratamiento farmacológico , Coagulasa , Escherichia coli , Estudios Retrospectivos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Oxacilina , Staphylococcus
16.
Environ Toxicol ; 38(5): 1196-1210, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36880448

RESUMEN

One of the important monitoring indicators of the air pollution is atmospheric fine particulate matter (PM2.5 ), which can induce lung inflammation after inhalation. Coelonin can alleviate PM2.5 -induced macrophage damage through anti-inflammation. However, its molecular mechanism remains unclear. We hypothesized that macrophage damage may involve the release of inflammatory cytokines, activation of inflammatory pathways, and pyrosis induced by inflammasome. In this study, we evaluated the anti-inflammation activity of coelonin in PM2.5 -induced macrophage and its mechanism of action. Nitric oxide (NO) and reactive oxygen species (ROS) production were measured by NO Assay kit and dichlorofluorescein-diacetate (DCFH-DA), and apoptosis were measured by Flow cytometry and TUNEL staining. The concentration of inflammatory cytokines production was measured with cytometric bead arrays and ELISA kits. The activation of NF-κB signaling pathway and NLRP3 inflammasome were measured by immunofluorescence, quantitative reverse transcription-polymerase chain reaction and western blot. As expected, coelonin pretreatment reduced NO production significantly as well as alleviated cell damage by decreasing ROS and apoptosis. It decreased generation of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in PM2.5 -induced RAW264.7 and J774A.1 cells. Moreover, coelonin markedly inhibited upregulating the expression of toll-like receptor (TLR)4 and cyclo-oxygenase (COX)-2, blocked activation of p-nuclear factor-kappa B (NF-κB) signaling pathway, and suppressed expression of NLRP3 inflammasome, ASC, GSDMD, IL-18 and IL-1ß. In conclusion, the results showed that coelonin could protect against PM2.5 -induced macrophage damage via suppressing TLR4/NF-κB/COX-2 signaling pathway and NLRP3 inflammasome activation in vitro.


Asunto(s)
Inflamasomas , FN-kappa B , FN-kappa B/metabolismo , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Ciclooxigenasa 2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptor Toll-Like 4/metabolismo , Transducción de Señal , Macrófagos/metabolismo , Citocinas/metabolismo , Interleucina-6 , Antiinflamatorios/farmacología , Material Particulado/toxicidad
17.
Drug Dev Res ; 84(7): 1468-1481, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37534761

RESUMEN

Distant metastasis is the primary reason for treatment failure in patients with nasopharyngeal carcinoma (NPC). In this study, we investigated the effect of ulinastatin (UTI) on NPC metastasis and its underlying mechanism. Highly-metastatic NPC cell lines S18 and 58F were treated with UTI and the effect on cell proliferation, migration, and invasion were determined by MTS and Transwell assays. S18 cells with luciferase-expressing (S18-1C3) were injected into the left hind footpad of nude mice to establish a model of spontaneous metastasis from the footpad to popliteal lymph node (LN). The luciferase messenger RNA (mRNA) was measured by quantitative polymerase chain reaction (qPCR), and the metastasis inhibition rate was calculated. Key molecular members of the UTI-related uPA, uPAR, and JAT/STAT3 signaling pathways were detected by qPCR and immunoblotting. UTI suppressed the migration and infiltration of S18 and 5-8F cells and suppressed the metastasis of S18 cells in vivo without affecting cell proliferation. uPAR expression decreased from 24 to 48 h after UTI treatment. The antimetastatic effect of UTI is partly due to the suppression of uPA and uPAR. UTI partially suppresses NPC metastasis by downregulating the expression of uPA and uPAR.


Asunto(s)
Neoplasias Nasofaríngeas , Animales , Ratones , Humanos , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patología , Ratones Desnudos , Línea Celular Tumoral , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/patología , Luciferasas , Movimiento Celular , Invasividad Neoplásica , Metástasis de la Neoplasia
18.
Int J Mol Sci ; 24(9)2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37176043

RESUMEN

Doxorubicin is one of the most widely used antitumor drugs and is currently produced via the chemical conversion method, which suffers from high production costs, complex product separation processes, and serious environmental pollution. Biocatalysis is considered a more efficient and environment-friendly method for drug production. The cytochrome daunorubicin C-14 hydroxylase (DoxA) is the essential enzyme catalyzing the conversion of daunorubicin to doxorubicin. Herein, the DoxA from Streptomyces peucetius subsp. caesius ATCC 27952 was expressed in Escherichia coli, and the rational design strategy was further applied to improve the enzyme activity. Eight amino acid residues were identified as the key sites via molecular docking. Using a constructed screening library, we obtained the mutant DoxA(P88Y) with a more rational protein conformation, and a 56% increase in bioconversion efficiency was achieved by the mutant compared to the wild-type DoxA. Molecular dynamics simulation was applied to understand the relationship between the enzyme's structural property and its substrate-binding efficiency. It was demonstrated that the mutant DoxA(P88Y) formed a new hydrophobic interaction with the substrate daunorubicin, which might have enhanced the binding stability and thus improved the catalytic activity. Our work lays a foundation for further exploration of DoxA and facilitates the industrial process of bio-production of doxorubicin.


Asunto(s)
Sistema Enzimático del Citocromo P-450 , Daunorrubicina , Daunorrubicina/metabolismo , Simulación del Acoplamiento Molecular , Sistema Enzimático del Citocromo P-450/metabolismo , Doxorrubicina/química , Conformación Proteica
19.
J Prosthet Dent ; 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-36966099

RESUMEN

STATEMENT OF PROBLEM: Stereolithography has been used to print zirconia ceramic crowns with acceptable dimensional accuracy and fracture force. However, studies that compared the fatigue resistance of zirconia crowns fabricated by stereolithography are lacking. PURPOSE: The purpose of this in vitro study was to compare the fracture and fatigue resistance of monolithic zirconia crowns printed by stereolithography apparatus (SLA) and digital light processing (DLP) with those of zirconia crowns milled by computer numerical control (CNC). MATERIAL AND METHODS: A total of 120 crowns were fabricated (n=40/material) and underwent 0, 104, 105, or 106 dynamic loading cycles of 30 to 300 N in artificial saliva, followed by a static fracture loading test (n=10). After fracture, 1 crown from each group was selected for fractography analysis by scanning electron microscopy (SEM). Data were statistically analyzed through 2-way ANOVA and post hoc analysis for multiple comparisons (α=.05). RESULTS: The 2-way ANOVA results showed that the mean ±standard deviation force at fracture was the highest for CNC (before fatigue loading: 5154 ±568 N, 104: 5735 ±1231 N, 105: 5523 ±797 N, and 106: 6007 ±1258 N), followed by DLP (before fatigue loading: 3381 ±612 N, 104: 4046 ±1146 N, 105: 2929 ±559 N, and 106: 3223 ±739 N), and the lowest for SLA (before fatigue loading: 2956 ±598 N, 104: 2757 ±421 N, 105: 3326 ±391 N, and 106: 3103 ±246 N) (P<.01). The fracture force of the crowns was not significantly affected by the number of fatigue cycles (P>.05). Fractography analysis showed that the number of arrest lines increased for crowns of all 3 materials. SEM images also showed the steps of SLA and DLP from their layer-by-layer printing and small cracks between layers of SLA after 106 loading cycles. CONCLUSIONS: The fracture force of monolithic zirconia crowns milled by CNC was significantly higher than that of zirconia crowns printed by stereolithography. Zirconia crowns printed by SLA and DLP could withstand typical clinical conditions, and their fracture and fatigue resistance exceeded the clinically estimated average occlusal forces.

20.
Prostate ; 82(15): 1438-1446, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35915875

RESUMEN

BACKGROUND: Stereotactic body radiation therapy (SBRT) has gradually been recognized as favorable curative treatment for localized prostate cancer (PC). However, the high rate of erectile dysfunction (ED) after traditional photon-based SBRT remains an ongoing challenge that greatly impacts the quality of life of PC survivors. Modern proton therapy allows higher conformal SBRT delivery and has the potential to reduce ED occurrence but its cost-effectiveness remains uninvestigated. METHODS: A Markov decision model was designed to evaluate the cost-effectiveness of proton SBRT versus photon SBRT in reducing irradiation-related ED. Base-case evaluation was performed on a 66-year-old (median age of PC) localized PC patient with normal pretreatment erectile function. Further, stratified analyses were performed for different age groups (50, 55, 60, 65, 70, and 75 years) and threshold analyses were conducted to estimate cost-effective scenarios. A Chinese societal willingness-to-pay (WTP) threshold (37,653 US dollars [$])/quality-adjusted life-year [QALY]) was adopted. RESULTS: For the base case, protons provided an additional 0.152 QALY at an additional cost of $7233.4, and the incremental cost-effectiveness ratio was $47,456.5/QALY. Protons was cost-effective for patients ≤62-year-old at the WTP of China (≤66-year-old at a WTP of $50,000/QALY; ≤73-year-old at a WTP of $100,000/QALY). For patients at median age, once the current proton cost ($18,000) was reduced to ≤$16,505.7 or the patient had a life expectancy ≥88 years, protons were cost-effective at the WTP of China. CONCLUSIONS: Upon assumption-based modeling, the results of current study support the use of proton SBRT in younger localized PC patients who are previously potent, for better preservation of erectile function. The findings await further validation using data from future comparative clinical trials.


Asunto(s)
Disfunción Eréctil , Neoplasias de la Próstata , Terapia de Protones , Anciano , Análisis Costo-Beneficio , Disfunción Eréctil/etiología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Próstata/radioterapia , Terapia de Protones/efectos adversos , Protones , Calidad de Vida
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