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1.
Phytomedicine ; 129: 155613, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38703659

RESUMEN

BACKGROUND: Psychological stress is associated with various diseases including liver dysfunction, yet effective intervention strategies remain lacking due to the unrevealed pathogenesis mechanism. PURPOSE: This study aims to explore the relevance between BMAL1-controlled circadian rhythms and lipoxygenase 15 (ALOX15)-mediated phospholipids peroxidation in psychological stress-induced liver injury, and to investigate whether hepatocyte phospholipid peroxidation signaling is involved in the hepatoprotective effects of a Chinese patent medicine, Pien Tze Huang (PZH). METHODS: Restraint stress models were established to investigate the underlying molecular mechanisms of psychological stress-induced liver injury and the hepatoprotective effects of PZH. Redox lipidomics based on liquid chromatography-tandem mass spectrometry was applied for lipid profiling. RESULTS: The present study discovered that acute restraint stress could induce liver injury. Notably, lipidomic analysis confirmed that phospholipid peroxidation was accumulated in the livers of stressed mice. Additionally, the essential core circadian clock gene Brain and Muscle Arnt-like Protein-1 (Bmal1) was altered in stressed mice. Circadian disruption in mice, as well as BMAL1-overexpression in human HepaRG cells, also appeared to have a significant increase in phospholipid peroxidation, suggesting that stress-induced liver injury is closely related to circadian rhythm and phospholipid peroxidation. Subsequently, arachidonate 15-lipoxygenase (ALOX15), a critical enzyme that contributed to phospholipid peroxidation, was screened as a potential regulatory target of BMAL1. Mechanistically, BMAL1 promoted ALOX15 expression via direct binding to an E-box-like motif in the promoter. Finally, this study revealed that PZH treatment significantly relieved pathological symptoms of psychological stress-induced liver injury with a potential mechanism of alleviating ALOX15-mediated phospholipid peroxidation. CONCLUSION: Our findings illustrate the critical role of BMAL1-triggered phospholipid peroxidation in psychological stress-induced liver injury and provide new insight into treating psychological stress-associated liver diseases by TCM intervention.

2.
Proc Natl Acad Sci U S A ; 121(13): e2315584121, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38507453

RESUMEN

The extractant-assisted transport of metal ions from aqueous to organic environments by liquid-liquid extraction has been widely used to separate and recover critical elements on an industrial scale. While current efforts focus on designing better extractants and optimizing process conditions, the mechanism that underlies ionic transport remains poorly understood. Here, we report a nonequilibrium process in the bulk aqueous phase that influences interfacial ion transport: the formation of metastable ion-extractant precipitates away from the liquid-liquid interface, separated from it by a depletion region without precipitates. Although the precipitate is soluble in the organic phase, the depletion region separates the two and ions are sequestered in a long-lived metastable state. Since precipitation removes extractants from the aqueous phase, even extractants that are sparingly soluble in water will continue to be withdrawn from the organic phase to feed the aqueous precipitation process. Solute concentrations in both phases and the aqueous pH influence the temporal evolution of the process and ionic partitioning between the precipitate and organic phase. Aqueous ion-extractant precipitation during liquid-liquid extraction provides a reaction path that can influence the extraction kinetics, which plays an important role in designing advanced processes to separate rare earths and other minerals.

3.
Food Chem ; 447: 139017, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38531304

RESUMEN

Long-term consumption of mixed fraudulent edible oils increases the risk of developing of chronic diseases which has been a threat to the public health globally. The complicated global supply-chain is making the industry malpractices had often gone undetected. In order to restore the confidence of consumers, traceability (and accountability) of every level in the supply chain is vital. In this work, we shown that machine learning (ML) assisted windowed spectroscopy (e.g., visible-band, infra-red band) produces high-throughput, non-destructive, and label-free authentication of edible oils (e.g., olive oils, sunflower oils), offers the feasibility for rapid analysis of large-scale industrial screening. We report achieving high-level of discriminant (AUC > 0.96) in the large-scale (n ≈ 11,500) of adulteration in olive oils. Notably, high clustering fidelity of 'spectral fingerprints' achieved created opportunity for (hypothesis-free) self-sustaining large database compilation which was never possible without machine learning. (137 words).


Asunto(s)
Contaminación de Alimentos , Aceites de Plantas , Aceites de Plantas/química , Aceite de Oliva/química , Aceite de Girasol , Análisis Espectral , Contaminación de Alimentos/análisis
4.
Cancer Immunol Immunother ; 73(5): 81, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38554184

RESUMEN

Poliovirus receptor-related immunoglobulin domain-containing protein, or PVRIG, is a newly discovered immune checkpoint that has emerged as a promising target for cancer immunotherapy. It is primarily expressed on activated T and natural killer (NK) cells, and once engaged with its ligand, PVRL2, it induces inhibitory signaling in T cells, thereby promoting the functional exhaustion of tumor-infiltrating lymphocytes (TILs). Here, we characterized IBI352g4a, a novel humanized anti-PVRIG antibody with Fc-competent function, explored the mechanism of its antitumor activity in preclinical models, and systemically evaluated the contribution of FcrR engagement to PVRIG blockade-induced antitumor activity. IBI352g4a binds to the extracellular domain of human PVRIG with high affinity (Kd = 0.53 nM) and specificity, and fully blocks the interaction between PVRIG and its ligand PVRL2. Unlike other immune checkpoints, IBI352g4a significantly induced NK cell activation and degranulation, but had a minimal effect on T-cell activation in in vitro functional assays. IBI352g4a induced strong antitumor effect in several preclinic models, through in vivo mechanism analysis we found that both NK and T cells contribute to the antitumor effect, but NK cells play predominant roles. Specifically, a single dose of IBI352g4a induced significant NK cell activation in TILs, but T-cell activation was observed only after the second dose. Moreover, the Fc effector function is critical for both NK cell activation and treatment efficacy in vitro and in vivo. Our study, for the first time, demonstrates that both NK activation and FcrR engagement are required for antitumor efficacy induced by PVRIG blockade.


Asunto(s)
Células Asesinas Naturales , Neoplasias , Humanos , Ligandos , Inmunoterapia , Linfocitos Infiltrantes de Tumor , Neoplasias/metabolismo
5.
iScience ; 27(2): 108951, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38323007

RESUMEN

Pain is a multi-dimensional phenomenon that encompasses both physical pain experienced physiologically and social pain experienced emotionally. The interactions between them are thought to lead to increased pain load. However, the effect of social pain on physical pain perception during interactions remains unclear. Four experiments were conducted merging physical and social pains to examine the behavioral pattern and neural mechanism of the effect of social pain on physical pain perception. Seemingly paradoxical effects of social pain were observed, which both facilitated and inhibited physical pain perception under different attention orientations. Brain imaging revealed that the posterior insula encoded the facilitatory effect, whereas the frontal pole engaged in the inhibitory effect. At a higher level, the thalamus further modulated both processes, playing a switch-like role under different concern statuses of social pain. These results provide direct evidence for the dual-pathway mechanism of the effect of social pain on physical pain.

6.
Biomed Eng Online ; 23(1): 4, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38191452

RESUMEN

BACKGROUND: In this study, an automatic corneal contour extraction algorithm with a shared model is developed to extract contours from dynamic corneal videos containing noise, which improves the accuracy of corneal biomechanical evaluation and clinical diagnoses. The algorithm does not require manual labeling and completes the unsupervised semantic segmentation of each frame in corneal dynamic deformation videos based on a fully convolutional deep-learning network using corneal geometry and texture information. RESULTS: We included 1027 corneal videos at Tianjin Eye Hospital (Nankai University Affiliated Eye Hospital) from May 2020 to November 2021. The videos were obtained by the ultra-high-speed Scheimpflug camera, and then we used the shared model mechanism to accelerate the segmentation of corneal regions in videos, effectively resist noise, determine corneal regions based on shape factors, and finally achieve automatic and accurate extraction of corneal region contours. The Intersection over Union (IoU) of the extracted and real corneal contours using this algorithm reached 95%, and the average overlap error was 0.05, implying that the extracted corneal contour overlapped almost completely with the real contour. CONCLUSIONS: Compared to other algorithms, the method introduced in this study does not require manual annotation of corneal contour data in advance and can still extract accurate corneal contours from noisy corneal videos with good repeatability.


Asunto(s)
Algoritmos , Córnea , Humanos , Córnea/diagnóstico por imagen , Semántica
7.
Nanoscale ; 15(45): 18415-18422, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37936481

RESUMEN

Colloidal quantum shells are spherical semiconductor quantum wells, which have shown strong promise as optical materials, particularly in classes of experiments requiring multiple excitons. The two-photon properties of CdS/CdSe/CdS quantum shell samples are studied here to demonstrate large non-linear absorption cross-sections while retaining advantageous multiexciton physics conferred by the geometrical structure. The quantum shells have large two-phonon cross sections (0.4-7.9 × 106 GM), which highlights their potential use in upconversion imaging in which large per particle two-photon absorption is critical. Time-resolved measurements confirmed that the quantum shells have long biexciton lifetime (>10 ns in the largest core samples reported here) and large gain bandwidth (>300 meV). The combination of these attributes with large two-photon cross sections makes the CdS/CdSe/CdS quantum shells excellent gain media for two-photon excitation. With a broad gain bandwidth and long gain lifetime, quantum shell solids support multimodal amplified spontaneous emission from excitons, biexcitons, and higher excited states. Thresholds for amplified spontaneous emission and lasing, which are as low as 1 mJ cm-2, are comparable to, or lower than, the thresholds reported for other colloidal materials.

8.
Proc Natl Acad Sci U S A ; 120(44): e2304148120, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37844213

RESUMEN

Premelting of ice, a quasi-liquid layer (QLL) at the surface below the melting temperature, was first postulated by Michael Faraday 160 y ago. Since then, it has been extensively studied theoretically and experimentally through many techniques. Existing work has been performed predominantly on hexagonal ice, at conditions close to the triple point. Whether the same phenomenon can persist at much lower pressure and temperature, where stacking disordered ice sublimates directly into water vapor, remains unclear. Herein, we report direct observations of surface premelting on ice nanocrystals below the sublimation temperature using transmission electron microscopy (TEM). Similar to what has been reported on hexagonal ice, a QLL is found at the solid-vapor interface. It preferentially decorates certain facets, and its thickness increases as the phase transition temperature is approached. In situ TEM reveals strong diffusion of the QLL, while electron energy loss spectroscopy confirms its amorphous nature. More significantly, the premelting observed in this work is thought to be related to the metastable low-density ultraviscous water, instead of ambient liquid water as in the case of hexagonal ice. This opens a route to understand premelting and grassy liquid state, far away from the normal water triple point.

9.
Aging Cell ; 22(10): e13970, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37622525

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disorder associated with α-synuclein aggregation and dopaminergic neuron loss in the midbrain. There is evidence that psychological stress promotes PD progression by enhancing glucocorticoids-related oxidative damage, however, the mechanisms involved are unknown. The present study demonstrated that plasma membrane phospholipid peroxides, as determined by phospholipidomics, triggered ferroptosis in dopaminergic neurons, which in turn contributed to stress exacerbated PD-like motor disorder in mice overexpressing mutant human α-synuclein. Using hormonomics, we identified that stress stimulated corticosteroid release and promoted 15-lipoxygenase-1 (ALOX15)-mediated phospholipid peroxidation. ALOX15 was upregulated by α-synuclein overexpression and acted as a fundamental risk factor in the development of chronic stress-induced parkinsonism and neurodegeneration. Further, we demonstrated the mechanism by which corticosteroids activated the PKC pathway and induced phosphatidylethanolamine-binding protein-1 (PEBP1) to form a complex with ALOX15, thereby facilitating ALOX15 to locate on the plasma membrane phospholipids. A natural product isolated from herbs, leonurine, was screened with activities of inhibiting the ALOX15/PEBP1 interaction and thereby attenuating membrane phospholipid peroxidation. Collectively, our findings demonstrate that stress increases the susceptibility of PD by driving membrane lipid peroxidation of dopaminergic neurons and suggest the ALOX15/PEBP1 complex as a potential intervention target.


Asunto(s)
Enfermedad de Parkinson , Ratones , Humanos , Animales , Enfermedad de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Neuronas Dopaminérgicas/metabolismo , Susceptibilidad a Enfermedades/metabolismo , Estrés Psicológico
10.
Atherosclerosis ; 379: 117183, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37549548

RESUMEN

BACKGROUND AND AIMS: The aberrant proliferation and migration of vascular smooth muscle cells (VSMCs) play an essential role in the pathogenesis of atherosclerosis (AS). Long noncoding RNAs (lncRNAs) have been reported as important regulators in a number of diseases. However, very little is known regarding the functional role of lncRNAs in governing proliferation and migration of VSMCs and AS development. METHODS: Both in vitro and in vivo assays were performed to investigate the role of lncRNA in the pathophysiology of AS. Our previous lncRNA arrays revealed that lncRNA RP4-639F20.1 was significantly decreased in atherosclerotic plaques. Lentivirus overexpressing RP4-639F20.1 and lncRNA RP4-639F20.1 silencing vectors (Si-lnc-RP4-639F20.1) were constructed and transfected in VSMCs. The in vitro functions of lncRNA were analyzed by CCK-8 assays, EdU assays, scratch wound assays, transwell assays, qRT-PCR and Western blot analyses. RNA fluorescence in situ hybridization, immunoprecipitation and mRNA microarrays were used to explore the underlying mechanism. Adeno-associated-virus-9 (AAV9) overexpressing RP4-639F20.1 was constructed and injected intravenously into ApoE-/- mice to explore the role of lncRNA in vivo. RESULTS: In vitro experiments showed that lncRNA RP4-639F20.1 interacted with THRAP3 and downregulated c-FOS expression. Both increase of lncRNA RP4-639F20.1 expression and knockdown of c-FOS inhibited the expression of MMP10 and VEGF-α in VSMCs and suppressed VSMCs proliferation and migration. In vivo experiments using ApoE-/- mice fed a high-fat diet demonstrated that lncRNA RP4-639F20.1 overexpression deterred atherosclerosis and decreased lipid levels in atherosclerotic lesions. Patients with coronary artery disease were found to have higher c-FOS levels than healthy individuals and c-FOS expression was positively correlated with the SYNTAX score of patients. CONCLUSIONS: Overall, these data indicated that lncRNA RP4-639F20.1/THRAP3/c-FOS pathway protects against the development of atherosclerosis by suppressing VSMCs proliferation and migration. LncRNA RP4-639F20.1 and c-FOS could represent potential therapeutic targets to ameliorate atherosclerosis-related diseases.


Asunto(s)
Aterosclerosis , Proteínas Proto-Oncogénicas c-fos , ARN Largo no Codificante , Factores de Transcripción , Animales , Ratones , Aterosclerosis/genética , Aterosclerosis/prevención & control , Aterosclerosis/metabolismo , Movimiento Celular , Proliferación Celular , Células Cultivadas , Hibridación Fluorescente in Situ , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratones Noqueados para ApoE
11.
J Phys Chem B ; 127(33): 7408-7415, 2023 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-37560941

RESUMEN

The macroscopic rheological response of a colloidal solution is highly correlated with the local microscopic structure, as revealed by an in situ Rheo-SAXS experiment with a high temporal resolution. Oscillatory shear can induce a strain-controlled ordering-to-disorder transition, resulting in a shear-thickening process that is different from the normal shear-thickening behavior that is driven by hydrodynamics and particle friction. We reveal that there is a complex time-dependent kinetics toward structural ordering under different applied strains. When the strain amplitude reaches a critical value that starts to induce disordering in the system, the pathway toward the dynamic equilibrium can also become highly non-monotonic. Within the same oscillatory cycle, there is a strong correlation of ordering with different phases of the oscillation, with the system oscillating between two dynamic metastable states.

13.
J Chem Theory Comput ; 19(11): 3237-3250, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37272711

RESUMEN

In this study, we report a simplified yet accurate general AMOEBA polarizable force field for combustion-interested molecular species, denoted as Combustion-AMOEBA or cAMOEBA. By eliminating the permanent atomic dipoles and quadrupoles, retaining the explicit polarization and defining the general atom types of each molecule species, including alkanes, alkenes, alkynes, alcohols, peroxides, and aldehydes, a simplified and general cAMOEBA force field was constructed and validated using the benchmark results obtained at the QCISD(T)/CBS level of theory. In this way, the tedious parametrization step for permanent atomic multipoles of each new molecule in the original AMOEBA (Poltype/MP2) force field could be avoided, hence providing the capability of accurate high-throughput calculation for a large number of molecules at lower computational cost. The averaged difference between the calculated transport parameters, σ and ε, for approximately 100 different molecules and four bath gases (He, Ne, Ar, and N2) using cAMOEBA and AMOEBA (Poltype/MP2) are of 0.09% and 1.27%, respectively, showing a good consistence of the general cAMOEBA force field with the original AMOEBA (Poltype/MP2) force field where the multipole force field parameters were obtained from quantum mechanical calculation for each small molecule. Our results also indicated that the Lorentz-Berthelot combination rule was more applicable than Waldman-Hagler for obtaining the molecular Lennard-Jones parameters of pure gases from one bath gas, while the Waldman-Hagler combination rule was better for obtaining such parameters from all four bath gases. The pure gas parameters obtained using cAMOEBA can be applied to develop high quality transport property database for combustion modeling.

14.
Science ; 380(6645): 609-616, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37167381

RESUMEN

Discovery of earth-abundant electrocatalysts to replace iridium for the oxygen evolution reaction (OER) in a proton exchange membrane water electrolyzer (PEMWE) represents a critical step in reducing the cost for green hydrogen production. We report a nanofibrous cobalt spinel catalyst codoped with lanthanum (La) and manganese (Mn) prepared from a zeolitic imidazolate framework embedded in electrospun polymer fiber. The catalyst demonstrated a low overpotential of 353 millivolts at 10 milliamperes per square centimeter and a low degradation for OER over 360 hours in acidic electrolyte. A PEMWE containing this catalyst at the anode demonstrated a current density of 2000 milliamperes per square centimeter at 2.47 volts (Nafion 115 membrane) or 4000 milliamperes per square centimeter at 3.00 volts (Nafion 212 membrane) and low degradation in an accelerated stress test.

15.
J Clin Invest ; 133(10)2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37183824

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the gradual loss of midbrain dopaminergic neurons in association with aggregation of α-synuclein. Oxidative damage has been widely implicated in this disease, though the mechanisms involved remain elusive. Here, we demonstrated that preferential accumulation of peroxidized phospholipids and loss of the antioxidant enzyme glutathione peroxidase 4 (GPX4) were responsible for vulnerability of midbrain dopaminergic neurons and progressive motor dysfunctions in a mouse model of PD. We also established a mechanism wherein iron-induced dopamine oxidation modified GPX4, thereby rendering it amenable to degradation via the ubiquitin-proteasome pathway. In conclusion, this study unraveled what we believe to be a novel pathway for dopaminergic neuron degeneration during PD pathogenesis, driven by dopamine-induced loss of antioxidant GPX4 activity.


Asunto(s)
Ferroptosis , Enfermedad de Parkinson , Ratones , Animales , Dopamina/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Neuronas Dopaminérgicas/metabolismo , Antioxidantes , Ferroptosis/genética , Enfermedad de Parkinson/metabolismo , Mesencéfalo/metabolismo , alfa-Sinucleína/metabolismo , Ubiquitinación
16.
Bioorg Chem ; 136: 106526, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37058782

RESUMEN

Two series of novel acridone derivatives were designed and synthesized, with their anticancer activity evaluated. Most of these compounds showed potent antiproliferative activity against cancer cell lines. Among them, compound C4 with dual 1,2,3-triazol moieties exhibited the most potent activity against Hep-G2 cells with IC50 value determined to be 6.29 ± 0.93 µM. Subsequent experiments showed that C4 could bind to and destabilize Kras gene promoter i-motif structure without significant interaction with its corresponding G-quadruplex. C4 could down-regulate Kras expression in Hep-G2 cells, possibly due to its interaction with the Kras i-motif. Further cellular studies indicated that C4 could induce apoptosis of Hep-G2 cells, possibly related to its effect on mitochondrial dysfunction. These results indicated that C4 could be further developed as a promising anticancer agent.


Asunto(s)
Antineoplásicos , Estructura Molecular , Relación Estructura-Actividad , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Antineoplásicos/farmacología , Antineoplásicos/química , Acridonas/farmacología , Proliferación Celular , Apoptosis
17.
Int Arch Allergy Immunol ; 184(7): 668-680, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36996762

RESUMEN

INTRODUCTION: Chicken eggs and cow's milk are two of the most common foods that cause allergic reactions in infants and young children, and there is a lack of precise diagnostic methods to identify the allergic state of these patients. The recently developed food allergen component-resolved diagnosis (CRD) may be a more accurate diagnosis method for food allergies. METHODS: One hundred children sensitized to egg white and milk crude extracts and diagnosed with or suspected allergic disease were included. The specific immunoglobulin E (sIgE) (s) of animal food allergen crude extracts (egg yolk, milk, shrimp, crab, cod, beef) and the main components of egg white and milk were tested. The sensitization characteristics, cross-reactivity, and clinical relevance were analyzed. RESULTS: The results of egg white-sensitized patients showed that ovalbumin (Gal d 2) had the highest positive rate of 100%. Compared with other pairwise combinations of egg allergens, the combination of egg white and Gal d 2 had higher diagnostic accuracy, with an AUC of 0.876 (95% CI: 0.801-0.951), a sensitivity of 88.9%, and a specificity of 75.9%. The positive rates of beta-lactoglobulin (Bos d 5) and alpha-lactoglobulin (Bos d 4) in the milk-sensitized children were comparable, 92% and 91%, respectively. The combination of crude milk extract and Bos d 4 had the highest diagnostic accuracy, with an AUC of 0.969 (95% CI: 0.938-0.999), a sensitivity of 100%, and a specificity of 82.7%. CONCLUSION: Among these subjects, our study found the main allergenic component of egg white was Gal d 2, and the main allergenic components of milk were Bos d 4 and Bos d 5. CRD may help identify egg/milk allergies and non-allergies.


Asunto(s)
Hipersensibilidad al Huevo , Hipersensibilidad a los Alimentos , Hipersensibilidad a la Leche , Animales , Femenino , Bovinos , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad al Huevo/diagnóstico , Hipersensibilidad a la Leche/diagnóstico , Alérgenos , China/epidemiología
18.
Biochim Biophys Acta Gene Regul Mech ; 1866(2): 194912, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36754277

RESUMEN

BACKGROUND: c-Kit protein is a signal transduction protein involved in multiple signal pathways, which play an important role in a variety of cellular events such as cell proliferation, apoptosis and differentiation. Special DNA secondary structures on the promoter of c-Kit gene, including G-quadruplex and i-motif structures, could act as "molecular switch" for gene transcriptional regulation, which are potentially important target for development of new anti-cancer drugs. METHODS: We screened and evaluated the effect of compounds on c-Kit through several experiments, including SPR, FRET, CD, MST, NMR, dual-luciferase reporter assay, Western blot, qPCR, immunofluorescence, MTT assay, colony formation, cell scrape, cell apoptosis, cell cycle analysis, and transwell assay. RESULTS: After extensive screening, we found that bisacridine derivative B05 had selective binding and stabilization to dual i-motif structures on c-Kit gene promoter, which could down-regulate c-Kit gene transcription and translation, resulting in inhibition of cell proliferation and metastasis. B05 exhibited potent anti-tumor activity on HGC-27 cells, and strongly suppressed tumor growth in HGC-27 xenograft mice model. CONCLUSIONS: B05 could interact with c-Kit promoter dual i-motif structures with excellent selectivity, which make it possible for selective regulation of gene transcription and translation. B05 could be further developed for selective anti-cancer agent targeting c-Kit promoter i-motifs. GENERAL SIGNIFICANCE: i-Motifs on different proto-oncogene promoters are diversified, and especially binding of dual i-motifs on the same promoter simultaneously could significantly down-regulate gene transcription with decreased dosage, and therefore increasing the selectivity. This new strategy shed bight light on development of selective DNA-targeting ligands.


Asunto(s)
Regulación de la Expresión Génica , Neoplasias , Humanos , Ratones , Animales , Regiones Promotoras Genéticas , Neoplasias/genética , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , ADN/genética , Transcripción Genética
19.
Plant Sci ; 331: 111661, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36813243

RESUMEN

For cereal crops, such as rice, the grain yield mainly comes from the accumulation of carbohydrates in the seed, which depends ultimately on photosynthesis during the growth period. To create early ripen variety, higher efficiency of photosynthesis is thus necessary to get higher grain yield with shorter growth period. In this study, flowering early was observed in the hybrid rice with overexpression of OsNF-YB4. Along with the flowering early, the hybrid rice also was shorter in plant height with less of leaves and internodes, but no changes of panicle length and leaf emergence. The grain yield was kept or even increased in the hybrid rice with shorter growth period. Transcription analysis revealed that Ghd7-Ehd1-Hd3a/RFT1 was activated early to promote the flowering transition in the overexpression hybrids. RNA-Seq study further showed that carbohydrate-related pathways were significantly altered in addition to circadian pathway. Notably, up-regulation of three pathways related to plant photosynthesis was observed, as well. Increased carbon assimilation with alteration of chlorophyll contents was subsequently detected in the following physiological experiments. All these results demonstrate that overexpression of OsNF-YB4 in the hybrid rice activates flowering early and improves photosynthesis resulting in better grain yield with shorter growth period.


Asunto(s)
Oryza , Oryza/metabolismo , Grano Comestible/genética , Fotosíntesis/genética , Hojas de la Planta/metabolismo , Clorofila/metabolismo , Regulación de la Expresión Génica de las Plantas
20.
Behav Res Ther ; 161: 104252, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36645948

RESUMEN

Patients with depression not only have to cope with depressive and physical symptoms but also face stigmatization due to mental illness. Pain is a clinical symptom of many patients with depression. However, it is unclear whether stigmatized experience associated with mental illness directly affects depressed patients' pain perception. Here, using the event reflection task, Study 1 (N = 95) examined whether stigmatized experiences due to depression would affect patients' self-reported pain assessment. Study 2 (N = 43) further employed thermal stimuli at different intensities to examine whether stigmatization would affect patients' evoked pain. We found that patients with depression who experienced stigmatization based on mental illness reported higher pain catastrophizing and performed increased pain perception for noxious stimuli than those who did not. Our studies provide first-hand experimental evidence of the effect of stigmatized experiences on depressed patients' pain perception. The findings contribute insights for improving clinical treatment, suggesting that interventions should minimize stigmatization associated with mental illness to help patients maintain healthier physical and psychological states.


Asunto(s)
Trastornos Mentales , Humanos , Percepción del Dolor , Dolor/psicología , Estado de Salud , Autoinforme , Depresión/psicología
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