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2.
Cancer Sci ; 115(7): 2318-2332, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705575

RESUMO

Persistent activation of estrogen receptor alpha (ERα)-mediated estrogen signaling plays a pivotal role in driving the progression of estrogen receptor positive (ER+) breast cancer (BC). In the current study, LINC00173, a long non-coding RNA, was found to bind both ERα and lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNFα) factor (LITAF), then cooperatively to inhibit ERα protein degradation by impeding the nuclear export of ERα. Concurrently, LITAF was found to attenuate TNFα transcription after binding to LINC00173, and this attenuating transcriptional effect was quite significant under lipopolysaccharide stimulation. Distinct functional disparities between estrogen subtypes emerge, with estradiol synergistically promoting ER+ BC cell growth with LINC00173, while estrone (E1) facilitated LITAF-transcriptional activation. In terms of therapeutic significance, silencing LINC00173 alongside moderate addition of E1 heightened TNFα and induced apoptosis, effectively inhibiting ER+ BC progression.


Assuntos
Neoplasias da Mama , Receptor alfa de Estrogênio , Estrona , RNA Longo não Codificante , Fatores de Transcrição , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Receptor alfa de Estrogênio/metabolismo , Receptor alfa de Estrogênio/genética , Feminino , Estrona/metabolismo , Estrona/farmacologia , Estrona/análogos & derivados , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Fator de Necrose Tumoral alfa/metabolismo , Células MCF-7 , Linhagem Celular Tumoral , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Animais , Camundongos , Inativação Gênica
3.
Small ; 20(10): e2307138, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37875766

RESUMO

Covalent organic frameworks (COFs) offer a desirable platform to explore multichoromophoric arrays for photocatalytic conversion. Symmetric arrangement of choromophoric modules over π-extended frameworks enhances exciton delocalization while impairing excitation density and accordingly photochemical reactivity. Herein, a photoisomerization-driven strategy is proposed to break the excited-state symmetry of ketoenamine-linked COFs with multichoromophoric arrays. Incorporating electron-withdrawing benzothiadiazole facilitates the ultrafast excited-state intramolecular proton transfer (ESIPT) from enamine to keto within 140 fs, resulting in partially enolized COF isomers. The hybrid linkages containing imine and enamine bonds at the node of framework alter the symmetry of electronic structure and enforce the photoinduced charge separation. Increasing the imine-to-enamine ratio further promotes the electron transferred number in a long range, thereby affording the optimum photocatalytic hydrogen evolution rate. This work put forward an ESIPT-induced photoisomerization to build a symmetry-breaking COF with weakened exciton effect and enhanced photochemical reactivity.

4.
New Phytol ; 242(5): 2043-2058, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38515251

RESUMO

MicroRNAs are essential in plant development and stress resistance, but their specific roles in drought stress require further investigation. Here, we have uncovered that a Populus-specific microRNAs (miRNA), miR6445, targeting NAC (NAM, ATAF, and CUC) family genes, is involved in regulating drought tolerance of poplar. The expression level of miR6445 was significantly upregulated under drought stress; concomitantly, seven targeted NAC genes showed significant downregulation. Silencing the expression of miR6445 by short tandem target mimic technology significantly decreased the drought tolerance in poplar. Furthermore, 5' RACE experiments confirmed that miR6445 directly targeted NAC029. The overexpression lines of PtrNAC029 (OE-NAC029) showed increased sensitivity to drought compared with knockout lines (Crispr-NAC029), consistent with the drought-sensitive phenotype observed in miR6445-silenced strains. PtrNAC029 was further verified to directly bind to the promoters of glutathione S-transferase U23 (GSTU23) and inhibit its expression. Both Crispr-NAC029 and PtrGSTU23 overexpressing plants showed higher levels of PtrGSTU23 transcript and GST activity while accumulating less reactive oxygen species (ROS). Moreover, poplars overexpressing GSTU23 demonstrated enhanced drought tolerance. Taken together, our research reveals the crucial role of the miR6445-NAC029-GSTU23 module in enhancing poplar drought tolerance by regulating ROS homeostasis. This finding provides new molecular targets for improving the drought resistance of trees.


Assuntos
Adaptação Fisiológica , Secas , Regulação da Expressão Gênica de Plantas , Glutationa Transferase , MicroRNAs , Proteínas de Plantas , Populus , Espécies Reativas de Oxigênio , Populus/genética , Populus/fisiologia , Populus/enzimologia , MicroRNAs/genética , MicroRNAs/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Adaptação Fisiológica/genética , Plantas Geneticamente Modificadas , Estresse Fisiológico/genética , Sequestradores de Radicais Livres/metabolismo , Sequência de Bases , Genes de Plantas , Regiões Promotoras Genéticas/genética , Resistência à Seca
5.
Opt Lett ; 49(11): 2954-2957, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824301

RESUMO

Low-cost nanocomposite metasurfaces have demonstrated attractive potential to replace the equivalent dielectric metasurfaces for light engineering. However, the resonance characteristics of embedded structures in nanocomposite metasurfaces have not been further analyzed beyond the effective refractive index. Herein, we have proposed customizable polarization-selective narrowband meta-filters using ultraviolet-curable (UV) nanocomposites. As an additional degree of freedom, near-field effects between highly concentrated doped nanoparticles can enhance the Mie resonance of the low aspect ratio (AR = 0.2) meta-units. The surface lattice resonances (SLRs) of meta-filters can be coupled with enhanced Mie resonances of individual meta-units to realize tunable narrowband (FWHM ∼0.007λ) reflections with intensities near unity. Meanwhile, the polarization-selective properties of the reflection peaks can be tuned by optimizing the asymmetric lattice. Such proposed new-generation customizable meta-filters will offer, to our knowledge, novel strategies for filtering specific near-infrared polarized fluorescence in the integrated imaging systems.

6.
Langmuir ; 40(20): 10486-10491, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38728233

RESUMO

In view of the excellent prospects of gene therapy and the potential safety and immunogenicity issues challenged by viral vectors, it is of great significance to develop a nonviral vector with low toxicity and low cost. In this work, we report a chitosan nanoparticle (CSNP) to be used as a gene vector prepared through a facile solvent-exchange strategy. Chitosan is first dissolved in ionic liquid 1-ethyl-3-methylimidazolium acetate (EMIM Ac), and then, the solvent is exchanged with water/phosphate-buffered saline (PBS) to remove ionic liquid, forming a final CSNP dispersion after ultrasonication. The prepared CSNP shows a positive surface charge and can condense green fluorescent protein-encoding plasmid (pGFP) at weight ratios (CSNP/pGFP) of 5/1 or higher. Dynamic light scattering size and ζ-potential characterization and gel retardation results confirm the formation of CSNP/pGFP complexes. Compared with plain pGFP, efficient cellular internalization and significantly enhanced green fluorescent protein (GFP) expression are observed by using CSNP as a plasmid vector. Benefitting from the intrinsic biocompatibility, low cost, low immunogenicity, and abundant sources of chitosan, as well as the facile preparation and the efficient gene transfection capacity of CSNP, it is believed that this CSNP could be used as a nonviral gene vector with great clinical translational potentials.


Assuntos
Quitosana , Proteínas de Fluorescência Verde , Nanopartículas , Plasmídeos , Solventes , Quitosana/química , Nanopartículas/química , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Humanos , Solventes/química , Plasmídeos/química , Plasmídeos/genética , Técnicas de Transferência de Genes , Transfecção/métodos , Tamanho da Partícula , Células HeLa
7.
Nature ; 560(7718): 382-386, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089911

RESUMO

Tumour cells evade immune surveillance by upregulating the surface expression of programmed death-ligand 1 (PD-L1), which interacts with programmed death-1 (PD-1) receptor on T cells to elicit the immune checkpoint response1,2. Anti-PD-1 antibodies have shown remarkable promise in treating tumours, including metastatic melanoma2-4. However, the patient response rate is low4,5. A better understanding of PD-L1-mediated immune evasion is needed to predict patient response and improve treatment efficacy. Here we report that metastatic melanomas release extracellular vesicles, mostly in the form of exosomes, that carry PD-L1 on their surface. Stimulation with interferon-γ (IFN-γ) increases the amount of PD-L1 on these vesicles, which suppresses the function of CD8 T cells and facilitates tumour growth. In patients with metastatic melanoma, the level of circulating exosomal PD-L1 positively correlates with that of IFN-γ, and varies during the course of anti-PD-1 therapy. The magnitudes of the increase in circulating exosomal PD-L1 during early stages of treatment, as an indicator of the adaptive response of the tumour cells to T cell reinvigoration, stratifies clinical responders from non-responders. Our study unveils a mechanism by which tumour cells systemically suppress the immune system, and provides a rationale for the application of exosomal PD-L1 as a predictor for anti-PD-1 therapy.


Assuntos
Antígeno B7-H1/imunologia , Exossomos/metabolismo , Tolerância Imunológica/imunologia , Melanoma/imunologia , Receptor de Morte Celular Programada 1/imunologia , Evasão Tumoral/imunologia , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/sangue , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Humanos , Tolerância Imunológica/efeitos dos fármacos , Interferon gama/sangue , Interferon gama/imunologia , Melanoma/tratamento farmacológico , Melanoma/patologia , Camundongos , Camundongos Nus , Metástase Neoplásica , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Evasão Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Nano Lett ; 23(23): 11193-11202, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38039401

RESUMO

The topically administered glaucoma medications usually encounter serious precorneal drug loss and low corneal penetration, leading to a low bioavailability. In addition, due to the complexity of glaucoma etiology, a single medication is often insufficient. In this work, we report a novel dendritic oligoethylenimine decorated liposome for codelivery of two antiglaucoma drugs, latanoprost and timolol. The liposome showed a uniform nanoscopic particle size, positive surface charge, and excellent dual-drug loading capacity. A prolonged precorneal retention is observed by using this liposomal delivery system. This liposomal delivery system presents increased cellular uptake and tight junctions opening capacity, contributing respectively to the transcellular and paracellular permeation, thereby enhancing the trans-corneal transportation. Following topical administration of one eye drop in brown Norway rats, the dual-drug-loaded liposome formulation resulted in a sustained and effective intraocular pressure reduction as long as 5 days, without inducing ocular inflammation, discomfort, and tissue damage.


Assuntos
Glaucoma , Lipossomos , Ratos , Animais , Lipossomos/uso terapêutico , Agentes Antiglaucoma , Glaucoma/tratamento farmacológico , Timolol/farmacologia , Timolol/uso terapêutico , Administração Tópica , Sistemas de Liberação de Medicamentos
9.
Opt Express ; 31(19): 30092-30107, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37710559

RESUMO

Multicolor two-photon endomicroscopy has become a highly competitive tool for functional imaging in biomedical researches. However, to make the imaging system miniature and applicable for freely behaving animal brain activity, metalenses have received much attention in compact imaging systems. For high resolution multicolor imaging and maximizing fluorescence collection, there is a challenge metalenses faced to achieve large numerical aperture (NA) and focus the NIR excitation and VIS emission lights of multiple fluorophores to the same distance simultaneously because of the limitation of the group delay range of the meta-units. In this paper, we proposed a high NA and polarization-insensitive ultra-broadband achromatic metalens specifically for achromatically focusing the excitation and emission light of multiple fluorophores commonly used in neuroscience studies. TiO2 and Si meta-unit libraries composed of heights, widths and the corresponding phase and group delay were constructed, and the optimal meta-units were selected by particle swarm optimization algorithm to engineer the dispersion of metalens in the VIS band and NIR band, respectively. Combining dispersion engineering with spatial multiplexing, the proposed metalens achieved the maximal effective NA up to 0.8 and large achromatic bandwidth ranging from 500 nm to 1050 nm, which exhibited the coefficient of variation of focal lengths was only 3.41%. The proposed achromatic metalens could successfully achromatically focus different fluorescence with any polarization, which was suitable for most fluorophores. Our results firmly establish that the proposed metalens can open the door to high resolution and minimally invasive multicolor two-photon functional imaging in intravital deep brain.

10.
Nature ; 550(7674): 133-136, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28953887

RESUMO

Targeted BRAF inhibition (BRAFi) and combined BRAF and MEK inhibition (BRAFi and MEKi) therapies have markedly improved the clinical outcomes of patients with metastatic melanoma. Unfortunately, the efficacy of these treatments is often countered by the acquisition of drug resistance. Here we investigated the molecular mechanisms that underlie acquired resistance to BRAFi and to the combined therapy. Consistent with previous studies, we show that resistance to BRAFi is mediated by ERK pathway reactivation. Resistance to the combined therapy, however, is mediated by mechanisms independent of reactivation of ERK in many resistant cell lines and clinical samples. p21-activated kinases (PAKs) become activated in cells with acquired drug resistance and have a pivotal role in mediating resistance. Our screening, using a reverse-phase protein array, revealed distinct mechanisms by which PAKs mediate resistance to BRAFi and the combined therapy. In BRAFi-resistant cells, PAKs phosphorylate CRAF and MEK to reactivate ERK. In cells that are resistant to the combined therapy, PAKs regulate JNK and ß-catenin phosphorylation and mTOR pathway activation, and inhibit apoptosis, thereby bypassing ERK. Together, our results provide insights into the molecular mechanisms underlying acquired drug resistance to current targeted therapies, and may help to direct novel drug development efforts to overcome acquired drug resistance.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Melanoma/tratamento farmacológico , Melanoma/genética , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Mutação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/efeitos dos fármacos , Quinases Ativadas por p21/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/química , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/enzimologia , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/química , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-raf/química , Proteínas Proto-Oncogênicas c-raf/metabolismo , Serina-Treonina Quinases TOR/metabolismo , beta Catenina/química , beta Catenina/metabolismo , Quinases Ativadas por p21/antagonistas & inibidores , Quinases Ativadas por p21/genética
11.
Int J Mol Sci ; 24(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36901852

RESUMO

Nuclear Factor-Y (NF-Y), composed of three subunits NF-YA, NF-YB and NF-YC, exists in most of the eukaryotes and is relatively conservative in evolution. As compared to animals and fungi, the number of NF-Y subunits has significantly expanded in higher plants. The NF-Y complex regulates the expression of target genes by directly binding the promoter CCAAT box or by physical interaction and mediating the binding of a transcriptional activator or inhibitor. NF-Y plays an important role at various stages of plant growth and development, especially in response to stress, which attracted many researchers to explore. Herein, we have reviewed the structural characteristics and mechanism of function of NF-Y subunits, summarized the latest research on NF-Y involved in the response to abiotic stresses, including drought, salt, nutrient and temperature, and elaborated the critical role of NF-Y in these different abiotic stresses. Based on the summary above, we have prospected the potential research on NF-Y in response to plant abiotic stresses and discussed the difficulties that may be faced in order to provide a reference for the in-depth analysis of the function of NF-Y transcription factors and an in-depth study of plant responses to abiotic stress.


Assuntos
Regulação da Expressão Gênica , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Regiões Promotoras Genéticas , Estresse Fisiológico/genética , Fator de Ligação a CCAAT/genética
12.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36902250

RESUMO

F-box proteins are important components of eukaryotic SCF E3 ubiquitin ligase complexes, which specifically determine protein substrate proteasomal degradation during plant growth and development, as well as biotic and abiotic stress. It has been found that the FBA (F-box associated) protein family is one of the largest subgroups of the widely prevalent F-box family and plays significant roles in plant development and stress response. However, the FBA gene family in poplar has not been systematically studied to date. In this study, a total of 337 F-box candidate genes were discovered based on the fourth-generation genome resequencing of P. trichocarpa. The domain analysis and classification of candidate genes revealed that 74 of these candidate genes belong to the FBA protein family. The poplar F-box genes have undergone multiple gene replication events, particularly in the FBA subfamily, and their evolution can be attributed to genome-wide duplication (WGD) and tandem duplication (TD). In addition, we investigated the P. trichocarpa FBA subfamily using the PlantGenIE database and quantitative real-time PCR (qRT-PCR); the results showed that they are expressed in the cambium, phloem and mature tissues, but rarely expressed in young leaves and flowers. Moreover, they are also widely involved in the drought stress response. At last, we selected and cloned PtrFBA60 for physiological function analysis and found that it played an important role in coping with drought stress. Taken together, the family analysis of FBA genes in P. trichocarpa provides a new opportunity for the identification of P. trichocarpa candidate FBA genes and elucidation of their functions in growth, development and stress response, thus demonstrating their utility in the improvement of P. trichocarpa.


Assuntos
Proteínas F-Box , Família Multigênica , Secas , Genoma de Planta , Genes de Plantas , Proteínas F-Box/genética , Estresse Fisiológico/genética , Filogenia , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas
13.
Angew Chem Int Ed Engl ; 62(52): e202310972, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-37936564

RESUMO

In-plane ionic conduction over two-dimensional (2D) materials is desirable for flexible electronics. Exfoliating 2D covalent organic frameworks (COFs) towards a few layers is highly anticipated, whereas most examples remain robust via π-stacking against the interlayered dislocation. Herein, we synthesize a phosphine-amine-linked 2D COF by a nucleophilic substitution reaction of phosphazene with amines. The synthesized COF is crystalline, and stacks in an AB-staggered fashion, wherein the AB dual layers are interlocked by embedding P-Cl bonds from one to another layer, and the non-interlocked layers are readily delaminated. Therefore, in situ post-quaternization over phosphazene can improve the ionization of backbones, accompanied by layered exfoliation. The ultrathin nanosheets can decouple lithium salts for fast solid-state ion transport, achieving a high conductivity and low activation energy. Our findings explore the P-N substitution reaction for COF crystallization and demonstrate that the staggered stacking 2D COFs are readily exfoliated for designing solid electrolytes.

14.
Small ; 18(24): e2201275, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35585681

RESUMO

Two-dimensional covalent organic frameworks (2D COFs) offer a designable platform to explore porous polyelectrolyte frameworks with periodic ionic skeletons and uniform pore channels. However, the crystallinity of ionized 2D COF is often far from satisfactory as the electrostatic assembly of structures impedes the ordered layered arrangement. Here, a multivariate synthetic strategy to synthesize a highly crystalline squaraine (SQ)-linked zwitterionic 2D COF is proved. A neutral aldehyde monomer copolymerizes with squaric acid (SA) and amines in a controlled manner, resulting in the ionized COF with linkage heterogeneity in one tetragonal framework. Thus, the zwitterions of SQ are spatially isolated to minimize the electrostatic interaction and maintain the highly ordered layered stacking. With the addition of 85%-90% SA (relative to a total of aldehydes and SA), a fully SQ-linked zwitterionic 2D COF is achieved by the in-situ conversion of imine to SQ linkages. Such a highly crystalline SQ-linked COF promotes absorptivity in a full spectrum and photothermal conversion performances, and in turn, it exhibits enhanced solar-to-vapor generation with an efficiency of as high as 92.19%. These results suggest that synthetically regulating charge distribution is desirable to constitute a family of new crystalline polyelectrolyte frameworks.


Assuntos
Estruturas Metalorgânicas , Ciclobutanos , Iminas/química , Fenóis , Polieletrólitos , Porosidade
15.
BMC Neurosci ; 23(1): 54, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-36163017

RESUMO

BACKGROUND: Exercise boosts the health of some brain parts, such as the hippocampus and hypothalamus. Several studies show that long-term exercise improves spatial learning and memory, enhances hypothalamic leptin sensitivity, and regulates energy balance. However, the effect of exercise on the hippocampus and hypothalamus is not fully understood. The study aimed to find epigenetic modifications or changes in gene expression of the hippocampus and hypothalamus due to exercise. METHODS: Male C57BL/6 mice were randomly divided into sedentary and exercise groups. All mice in the exercise group were subjected to treadmill exercise 5 days per week for 1 h each day. After the 12-week exercise intervention, the hippocampus and hypothalamus tissue were used for RNA-sequencing or molecular biology experiments. RESULTS: In both groups, numerous differentially expressed genes of the hippocampus (up-regulated: 53, down-regulated: 49) and hypothalamus (up-regulated: 24, down-regulated: 40) were observed. In the exercise group, increased level of N6-methyladenosine (m6A) was observed in the hippocampus and hypothalamus (p < 0.05). Furthermore, the fat mass and obesity-associated gene (FTO) of the hippocampus and hypothalamus were down-regulated in the exercise group (p < 0.001). In addition, the Fto co-expression genes of the mouse brain were studied and analyzed using database to determine the potential roles of exercise-downregulated FTO in the brain. CONCLUSION: The findings demonstrate that long-term exercise might elevates the levels of m6A-tagged transcripts in the hippocampus and hypothalamus via down-regulation of FTO. Hence, exercise might be an effective intervention for epigenetic modification.


Assuntos
Leptina , Animais , Epigênese Genética , Hipocampo/metabolismo , Hipotálamo/metabolismo , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA/metabolismo
16.
J Clin Pharm Ther ; 47(11): 1811-1819, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36101489

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Olanzapine is an atypical antipsychotic drug used for mental disorders. There are limited studies providing sufficient pharmacokinetic data, thus the variability of concentrations of olanzapine used in Chinese paediatric patients aged 10 to 17 years remains to be evaluated. METHODS: Therapeutic drug monitoring data were collected from 151 paediatric patients aged 10 to 17 years who received olanzapine. The model was developed with a NONMEM software program. The final model validation and evaluation were assessed by bootstrap, diagnostic scatter plots, and normalized prediction distribution error (NPDE). Regimens of different dosages were simulated to reach the target concentration levels of 20 ng/ml, by using the final model with typical parameters. RESULTS: The one-compartment model was considered the best fit for the data. Typical estimates of the absorption rate constant (Ka), apparent clearance (CL/F), and apparent distribution volume (V/F) in the final model were 0.142 h-1 , 15.4 L/h, and 322 L, respectively. Sex and concomitant valproate (VPA) were included as significant predictors of olanzapine clearance, which was described by the following equation: CL/F = 15.4 × (1 + 0.546 × SEX) × (1 + 0.264 × VPA). Results of Monte-Carlo simulation suggested that male paediatric patients with concomitant VPA were advised to take no less than 15 mg per day of olanzapine orally, and in female paediatric patients with concomitant VPA, a dosing regimen of 10 mg may be sufficient to achieve the therapeutic range of olanzapine. WHAT IS NEW AND CONCLUSION: Our results identified concomitant valproate and sex as significant covariates in olanzapine population pharmacokinetics. Our model may be a useful tool for recommending dosage adjustments for physicians. The pharmacokinetics of olanzapine in patients aged 10 to 17 years was generally similar to that of adults and the elderly.


Assuntos
Antipsicóticos , Ácido Valproico , Adulto , Criança , Humanos , Masculino , Feminino , Idoso , Olanzapina , Antipsicóticos/uso terapêutico , Cinética , China , Modelos Biológicos
17.
Lab Invest ; 101(3): 369-380, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33268842

RESUMO

NLRP3 inflammasome activation, which can be triggered by reactive oxygen species (ROS), contributes to nonalcoholic steatohepatitis (NASH) progression. Exercise is an effective therapeutic strategy for NASH. However, whether exercise prevents NLRP3 activation in NASH has not been investigated. Here, we investigated the effect of exercise on NLRP3 inflammasome in mice with high-fat diet (HFD)-induced or methionine and choine-deficient (MCD) diet-induced NASH and explored whether adropin, a metabolic peptide hormone shown to inhibit inflammation, mediates an exercise-induced benefit against NLRP3 inflammasome activation. Exercise alleviated diet-induced hepatic steatosis, inflammation, and fibrosis. Importantly, exercise significantly reduced the expression of NLRP3 inflammasome components, decreased Caspase-1 enzymatic activity, normalized IL-1ß production, and suppressed ROS overproduction in HFD-fed and MCD diet-fed mice. The exercise-elicited NLRP3 inflammasome inhibition was accompanied by increased adropin levels. Moreover, serum adropin levels were negatively correlated with serum IL-1ß levels. We further explored the effect of adropin on the NLRP3 inflammasome in palmitic acid (PA)-treated hepatocytes and Kupffer cells. Although adropin treatment did not significantly decrease the levels of all inflammasome components, it reduced the active Caspase-1 level, decreased Caspase-1 activity and downregulated IL-1ß expression in hepatocytes and Kupffer cells (KCs) treated with PA. Moreover, ROS levels in PA-stimulated hepatocytes and Kupffer cells were reduced upon adropin treatment. In summary, we demonstrated that the inhibitory effect of exercise on NLRP3 inflammasome activation was associated with adropin induction, resulting in NASH improvement.


Assuntos
Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Dieta Hiperlipídica/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Espécies Reativas de Oxigênio/metabolismo
18.
New Phytol ; 229(4): 2238-2250, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33091182

RESUMO

Heat-stressed Arabidopsis plants release heterochromatin-associated transposable element (TE) silencing, yet it is not accompanied by major reductions of epigenetic repressive modifications. In this study, we explored the functional role of histone H1 in repressing heterochromatic TEs in response to heat stress. We generated and analyzed RNA and bisulfite-sequencing data of wild-type and h1 mutant seedlings before and after heat stress. Loss of H1 caused activation of pericentromeric Gypsy elements upon heat treatment, despite these elements remaining highly methylated. By contrast, nonpericentromeric Copia elements became activated concomitantly with loss of DNA methylation. The same Copia elements became activated in heat-treated chromomethylase 2 (cmt2) mutants, indicating that H1 represses Copia elements through maintaining DNA methylation under heat. We discovered that H1 is required for TE repression in response to heat stress, but its functional role differs depending on TE location. Strikingly, H1-deficient plants treated with the DNA methyltransferase inhibitor zebularine were highly tolerant to heat stress, suggesting that both H1 and DNA methylation redundantly suppress the plant response to heat stress.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/fisiologia , Elementos de DNA Transponíveis , Resposta ao Choque Térmico , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Metilação de DNA , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/genética , Histonas/metabolismo
19.
New Phytol ; 230(5): 1868-1882, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33629353

RESUMO

Drought is one of the primary abiotic stresses, seriously implicating plant growth and productivity. Stomata play a crucial role in regulating drought tolerance. However, the molecular mechanism on stomatal movement-mediated drought tolerance remains unclear. Using genetic, molecular and biochemical techniques, we identified that the PdGNC directly activating the promoter of PdHXK1 by binding the GATC element, a hexokinase (HXK) synthesis key gene. Here, PdGNC, a member of the GATA transcription factor family, was greatly induced by abscisic acid and dehydration. Overexpressing PdGNC in poplar (Populus clone 717) resulted in reduced stomatal aperture with greater water-use efficiency and increased water deficit tolerance. By contrast, CRISPR/Cas9-mediated poplar mutant gnc exhibited increased stomatal aperture and water loss with reducing drought resistance. PdGNC activates PdHXK1 (a hexokinase synthesis key gene), resulting in a remarkable increase in hexokinase activity in poplars subjected to water deficit. Furthermore, hexokinase promoted nitric oxide (NO) and hydrogen peroxide (H2 O2 ) production in guard cells, which ultimately reduced stomatal aperture and increased drought resistance. Together, PdGNC confers drought stress tolerance by reducing stomatal aperture caused by NO and H2 O2 production via the direct regulation of PdHXK1 expression in poplars.


Assuntos
Populus , Ácido Abscísico , Secas , Regulação da Expressão Gênica de Plantas , Óxido Nítrico , Estômatos de Plantas , Populus/genética
20.
Opt Express ; 29(3): 3795-3807, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33770972

RESUMO

With the novel capabilities of engineering the optical wavefront at the nanoscale, the dielectric metalens has been utilized for fluorescence microscopy imaging system. However, the main technical difficulty is how to realize the achromatic focusing and light modulation simultaneously by a single-layer metalens in the two-photon excitation STED (TPE-STED) endomicroscopy imaging system. Herein, by combining the spatial multiplexing technology and vortex phase modulation, a single-layer multitasking vortex-metalens as a miniature microscopy objective on the end of fiber was proposed. The multitasking vortex-metalens with 36-sectors interleaving (diameter of 100 µm) could focus the excitation beam (1050 nm) and depletion beam (599 nm) to the same focal distance, modulate a doughnut-shaped depletion spot with vortex phase and reshape the focal spots to further make improvement in the quality and symmetry. According to the TPE-STED theory, a symmetrical effective fluorescent spot with the lateral resolution of 30 nm was obtained by the proposed metalens. Thus, with the advantage of ultra-compact and lightweight, we prospect that the subminiature multitasking metalens will help guide future developments in high-performance metalenses toward high-resolution and real-time images for deep biological tissue in vivo and enable scientific high-end miniature endomicroscopy imaging system.

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