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1.
Cell ; 170(5): 1028-1043.e19, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28841410

RESUMO

Cis-regulatory elements (CREs) are commonly recognized by correlative chromatin features, yet the molecular composition of the vast majority of CREs in chromatin remains unknown. Here, we describe a CRISPR affinity purification in situ of regulatory elements (CAPTURE) approach to unbiasedly identify locus-specific chromatin-regulating protein complexes and long-range DNA interactions. Using an in vivo biotinylated nuclease-deficient Cas9 protein and sequence-specific guide RNAs, we show high-resolution and selective isolation of chromatin interactions at a single-copy genomic locus. Purification of human telomeres using CAPTURE identifies known and new telomeric factors. In situ capture of individual constituents of the enhancer cluster controlling human ß-globin genes establishes evidence for composition-based hierarchical organization. Furthermore, unbiased analysis of chromatin interactions at disease-associated cis-elements and developmentally regulated super-enhancers reveals spatial features that causally control gene transcription. Thus, comprehensive and unbiased analysis of locus-specific regulatory composition provides mechanistic insight into genome structure and function in development and disease.


Assuntos
Sistemas CRISPR-Cas , Endonucleases/metabolismo , Técnicas Genéticas , Elementos Reguladores de Transcrição , Animais , Biotinilação , Células Cultivadas , Células-Tronco Embrionárias/metabolismo , Endonucleases/genética , Elementos Facilitadores Genéticos , Humanos , Células K562 , Camundongos , RNA Guia de Cinetoplastídeos/metabolismo , Telômero/metabolismo , Globinas beta/genética
2.
Proc Natl Acad Sci U S A ; 120(31): e2305027120, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37490539

RESUMO

Nonlinear disordered systems are not only a model system for fundamental studies but also in high demand for practical applications. However, optical nonlinearity based on intrinsic material response is weak in random scattering systems. Here, we propose and experimentally realize a highly nonlinear mapping between the scattering potential and the emerging light of a reconfigurable multiple-scattering cavity. A quantitative analysis of the degree of nonlinearity reveals its dependence on the number of scattering events. The effective order of nonlinear mapping can be tuned over a wide range at low optical lower. The strong nonlinear mapping enhances output intensity fluctuations and long-range correlations. The flexibility, robustness, and energy efficiency of our approach provides a versatile platform for exploring such nonlinear mappings for various applications.

3.
Proc Natl Acad Sci U S A ; 120(22): e2217735120, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37216557

RESUMO

High-power fiber laser amplifiers have enabled an increasing range of applications in industry, science, and defense. The power scaling for fiber amplifiers is currently limited by transverse mode instability. Most techniques for suppressing the instability are based on single- or few-mode fibers in order to output a clean collimated beam. Here, we study theoretically using a highly multimode fiber amplifier with many-mode excitation for efficient suppression of thermo-optical nonlinearity and instability. We find that the mismatch of characteristic length scales between temperature and optical intensity variations across the fiber generically leads to weaker thermo-optical coupling between fiber modes. Consequently, the transverse mode instability (TMI) threshold power increases linearly with the number of equally excited modes. When the frequency bandwidth of a coherent seed laser is narrower than the spectral correlation width of the multimode fiber, the amplified light maintains high spatial coherence and can be transformed to any target pattern or focused to a diffraction-limited spot by a spatial mask at either the input or output end of the amplifier. Our method simultaneously achieves high average power, narrow spectral width, and good beam quality, which are required for fiber amplifiers in various applications.

4.
Blood ; 142(4): 336-351, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-36947815

RESUMO

Structural variants (SVs) involving enhancer hijacking can rewire chromatin topologies to cause oncogene activation in human cancers, including hematologic malignancies; however, because of the lack of tools to assess their effects on gene regulation and chromatin organization, the molecular determinants for the functional output of enhancer hijacking remain poorly understood. Here, we developed a multimodal approach to integrate genome sequencing, chromosome conformation, chromatin state, and transcriptomic alteration for quantitative analysis of transcriptional effects and structural reorganization imposed by SVs in leukemic genomes. We identified known and new pathogenic SVs, including recurrent t(5;14) translocations that cause the hijacking of BCL11B enhancers for the allele-specific activation of TLX3 in a subtype of pediatric leukemia. Epigenetic perturbation of SV-hijacked BCL11B enhancers impairs TLX3 transcription, which are required for the growth of t(5;14) leukemia cells. By CRISPR engineering of patient-derived t(5;14) in isogenic leukemia cells, we uncovered a new mechanism whereby the transcriptional output of SV-induced BCL11B enhancer hijacking is dependent on the loss of DNA hypermethylation at the TLX3 promoter. Our results highlight the importance of the cooperation between genetic alteration and permissive chromatin as a critical determinant of SV-mediated oncogene activation, with implications for understanding aberrant gene transcription after epigenetic therapies in patients with leukemia. Hence, leveraging the interdependency of genetic alteration on chromatin variation may provide new opportunities to reprogram gene regulation as targeted interventions in human disease.


Assuntos
Cromatina , Leucemia , Humanos , Criança , Cromatina/genética , Elementos Facilitadores Genéticos , Cromossomos/metabolismo , Fatores de Transcrição/genética , Leucemia/genética , Proteínas Supressoras de Tumor/genética , Proteínas Repressoras/genética
5.
Plant Cell ; 34(7): 2688-2707, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35435234

RESUMO

Cambial development in the stems of perennial woody species is rigorously regulated by phytohormones. Auxin and gibberellin (GA) play crucial roles in stimulating cambial activity in poplar (Populus spp.). In this study, we show that the DELLA protein REPRESSOR of ga1-3 Like 1 (RGL1), AUXIN RESPONSE FACTOR 7 (ARF7), and Aux/INDOLE-3-ACETIC ACID 9 (IAA9) form a ternary complex that mediates crosstalk between the auxin and GA signaling pathways in poplar stems during cambial development. Biochemical analysis revealed that ARF7 physically interacts with RGL1 and IAA9 through distinct domains. The arf7 loss-of-function mutant showed markedly attenuated responses to auxin and GA, whereas transgenic poplar plants overexpressing ARF7 displayed strongly improved cambial activity. ARF7 directly binds to the promoter region of the cambial stem cell regulator WOX4 to modulate its expression, thus integrating auxin and GA signaling to regulate cambial activity. Furthermore, the direct activation of PIN-FORMED 1 expression by ARF7 in the RGL1-ARF7-IAA9 module increased GA-dependent cambial activity via polar auxin transport. Collectively, these findings reveal that the crosstalk between auxin and GA signaling mediated by the RGL1-ARF7-IAA9 module is crucial for the precise regulation of cambial development in poplar.


Assuntos
Proteínas de Arabidopsis , Populus , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo
6.
Proc Natl Acad Sci U S A ; 119(41): e2207089119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36191199

RESUMO

Remitted waves are used for sensing and imaging in diverse diffusive media from the Earth's crust to the human brain. Separating the source and detector increases the penetration depth of light, but the signal strength decreases rapidly, leading to a poor signal-to-noise ratio. Here, we show, experimentally and numerically, that wavefront shaping a laser beam incident on a diffusive sample enables an enhancement of remission by an order of magnitude at depths of up to 10 transport mean free paths. We develop a theoretical model which predicts the maximal remission enhancement. Our analysis reveals a significant improvement in the sensitivity of remitted waves to local changes of absorption deep inside diffusive media. This work illustrates the potential of coherent wavefront control for noninvasive diffuse wave imaging applications, such as diffuse optical tomography and functional near-infrared spectroscopy.


Assuntos
Encéfalo , Difusão , Humanos , Razão Sinal-Ruído
7.
Anal Chem ; 96(19): 7697-7705, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38697043

RESUMO

Dual/multimodal imaging strategies are increasingly recognized for their potential to provide comprehensive diagnostic insights in cancer imaging by harnessing complementary data. This study presents an innovative probe that capitalizes on the synergistic benefits of afterglow luminescence and magnetic resonance imaging (MRI), effectively eliminating autofluorescence interference and delivering a superior signal-to-noise ratio. Additionally, it facilitates deep tissue penetration and enables noninvasive imaging. Despite the advantages, only a limited number of probes have demonstrated the capability to simultaneously enhance afterglow luminescence and achieve high-resolution MRI and afterglow imaging. Herein, we introduce a cutting-edge imaging platform based on semiconducting polymer nanoparticles (PFODBT) integrated with NaYF4@NaGdF4 (Y@Gd@PFO-SPNs), which can directly amplify afterglow luminescence and generate MRI and afterglow signals in tumor tissues. The proposed mechanism involves lanthanide nanoparticles producing singlet oxygen (1O2) upon white light irradiation, which subsequently oxidizes PFODBT, thereby intensifying afterglow luminescence. This innovative platform paves the way for the development of high signal-to-background ratio imaging modalities, promising noninvasive diagnostics for cancer.


Assuntos
Elementos da Série dos Lantanídeos , Imageamento por Ressonância Magnética , Nanopartículas , Polímeros , Semicondutores , Imageamento por Ressonância Magnética/métodos , Animais , Elementos da Série dos Lantanídeos/química , Polímeros/química , Nanopartículas/química , Camundongos , Humanos , Gadolínio/química , Luminescência , Oxigênio Singlete/química , Ítrio/química , Fluoretos/química , Camundongos Nus
8.
Small ; 20(11): e2304088, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939310

RESUMO

The use of natural cartilage extracellular matrix (ECM) has gained widespread attention in the field of cartilage tissue engineering. However, current approaches for delivering functional scaffolds for osteoarthritis (OA) therapy rely on knee surgery, which is limited by the narrow and complex structure of the articular cavity and carries the risk of injuring surrounding tissues. This work introduces a novel cell microcarrier, magnetized cartilage ECM-derived scaffolds (M-CEDSs), which are derived from decellularized natural porcine cartilage ECM. Human bone marrow mesenchymal stem cells are selected for their therapeutic potential in OA treatments. Owing to their natural composition, M-CEDSs have a biomechanical environment similar to that of human cartilage and can efficiently load functional cells while maintaining high mobility. The cells are released spontaneously at a target location for at least 20 days. Furthermore, cell-seeded M-CEDSs show better knee joint function recovery than control groups 3 weeks after surgery in preclinical experiments, and ex vivo experiments reveal that M-CEDSs can rapidly aggregate inside tissue samples. This work demonstrates the use of decellularized microrobots for cell delivery and their in vivo therapeutic effects in preclinical tests.


Assuntos
Cartilagem Articular , Células-Tronco Mesenquimais , Osteoartrite , Animais , Suínos , Humanos , Cartilagem Articular/fisiologia , Engenharia Tecidual , Matriz Extracelular/química , Fenômenos Magnéticos , Alicerces Teciduais/química
9.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36151775

RESUMO

Biomedical data preprocessing and efficient computing can be as important as the statistical methods used to fit the data; data processing needs to consider application scenarios, data acquisition and individual rights and interests. We review common principles, knowledge and methods of integrated research according to the whole-pipeline processing mechanism diverse, coherent, sharing, auditable and ecological. First, neuromorphic and native algorithms integrate diverse datasets, providing linear scalability and high visualization. Second, the choice mechanism of different preprocessing, analysis and transaction methods from raw to neuromorphic was summarized on the node and coordinator platforms. Third, combination of node, network, cloud, edge, swarm and graph builds an ecosystem of cohort integrated research and clinical diagnosis and treatment. Looking forward, it is vital to simultaneously combine deep computing, mass data storage and massively parallel communication.


Assuntos
Algoritmos , Ecossistema , Humanos , Conhecimento
10.
BMC Microbiol ; 24(1): 53, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38341527

RESUMO

BACKGROUND: Compared with aerial plant tissues (such as leaf, stem, and flower), root-associated microbiomes play an indisputable role in promoting plant health and productivity. We thus explored the similarities and differences between rhizosphere and root endosphere bacterial community in the grafted apple system. RESULTS: Using pot experiments, three microhabitats (bulk soil, rhizosphere and root endosphere) samples were obtained from two-year-old apple trees grafted on the four different rootstocks. We then investigated the bacterial community composition, diversity, and co-occurrence network in three microhabitats using the Illumina sequencing methods. Only 63 amplicon sequence variants (ASVs) out of a total of 24,485 were shared in the rhizosphere and root endosphere of apple grafted on the four different rootstocks (M9T337, Malus hupehensis Rehd., Malus robusta Rehd., and Malus baccata Borkh.). The core microbiome contained 8 phyla and 25 families. From the bulk soil to the rhizosphere to the root endosphere, the members of the phylum and class levels demonstrated a significant enrichment and depletion pattern. Co-occurrence network analysis showed the network complexity of the rhizosphere was higher than the root endosphere. Most of the keystone nodes in both networks were classified as Proteobacteria, Actinobacteriota and Bacteroidetes and were low abundance species. CONCLUSION: The hierarchical filtration pattern existed not only in the assembly of root endosphere bacteria, but also in the core microbiome. Moreover, most of the core ASVs were high-abundance species, while the keystone ASVs of the network were low-abundance species.


Assuntos
Malus , Rizosfera , Humanos , Pré-Escolar , Microbiologia do Solo , Raízes de Plantas/microbiologia , Bactérias/genética , Solo/química
11.
BMC Microbiol ; 24(1): 34, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38262927

RESUMO

BACKGROUND: Frogs are critical economic animals essential to agricultural ecosystem equilibrium. However, Meningitis-like Infectious Disease (MID) often affects them in agricultural settings. While frog-associated microbiota contribute to elemental cycling and immunity, the effects of frog sex and health on gut bacteria remain understudied, and the relationship between frog habitat and soil microbes is unclear. We aimed to determine how frog sex, health status and habitat influence symbiotic bacteria and community assembly mechanism to provide guidance for sustainable frog farming and conservation. RESULTS: We employed 16S rRNA sequencing to investigate gut microbiota differences in relation to frog sex and health status. We also compared symbiotic communities in frog-aggregation, native and soybean soil on the farm. Results showed that gut bacterial ß-diversity and taxonomy were markedly influenced by frog sex and health. Healthy frogs had more robust gut bacterial metabolism than frogs infected with MID. Cooccurrence network analysis revealed that healthy female frogs had more complex microbial network structure than males; however, diseased males showed the greatest network complexity. The assembly mechanism of gut bacteria in male frogs was dominated by deterministic processes, whereas in female frogs it was dominated by stochastic processes. Among symbiotic bacteria in frog habitat soils, deterministic processes predominantly shaped the community assembly of soybean soil. In particular, soybean soil was enriched in pathogens and nitrogen functions, whereas frog-aggregation soil was markedly increased in sulphur respiration and hydrocarbon degradation. CONCLUSION: Our study reveals that sex mainly alters the interaction network and assembly mechanism of frog intestinal bacteria; MID infection significantly inhibits the metabolic functions of intestinal bacteria. Furthermore, diverse frog habitat soils could shape more symbiotic bacteria to benefit frog farming. Our findings provide new horizons for symbiotic bacteria among frogs, which could contribute to sustainable agriculture and ecological balance.


Assuntos
Bactérias , Microbiota , Feminino , Masculino , Animais , RNA Ribossômico 16S , Anuros , Nível de Saúde , Solo , Glycine max
12.
Opt Express ; 32(4): 6232-6240, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439331

RESUMO

We propose what we believe is a novel format conversion scheme using a few-mode fiber Bragg grating (FM-FBG) that can perform multichannel format conversion from carrier-suppressed return-to-zero (CSRZ) to non-return-to-zero (NRZ) for both LP01 and LP11. The multichannel spectral response of FM-FBG is designed according to the algebraic difference between the CSRZ and NRZ spectra outlines. Additionally, the FM-FBG response spectra of LP11 are designed to shift with that of LP01 by the WDM-MDM channel spacing for filtering both modes together. Numerical results demonstrate the successful conversion of both LP01 and LP11 channels, carrying four channels of 200-GHz-spaced CSRZ signals at 40 Gbit/s, into NRZ signals with a high Q-factor (exceeding 14 dB), and the converted NRZ signals exhibit clean and open eye diagrams. Furthermore, the performance analysis also shown that our proposed FM-FBG is robust to central wavelength detuning.

13.
J Vasc Surg ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38777158

RESUMO

OBJECTIVE: Spontaneous carotid artery dissections (sCADs) are the common cause of stroke in middle-aged and young people. There is still a lack of clinical classification to guide the management of sCAD. We reviewed our experience with 179 patients with sCAD and proposed a new classification for sCAD with prognostic and therapeutic significance. METHODS: This is a retrospective review of prospectively collected data from June 2018 to June 2023 of patients with sCAD treated at a large tertiary academic institution in an urban city in China. Based on imaging results, we categorize sCAD into four types: type Ⅰ, intramural hematoma or dissection with <70% luminal narrowing; type Ⅱ, intramural hematoma or dissection with ≥70% luminal narrowing; type Ⅲ, dissecting aneurysm; type ⅣA, extracranial carotid artery occlusion; and type ⅣB, tandem occlusion. We compared the clinical data and prognostic outcomes among various types of sCADs. RESULTS: A total of 179 patients and 197 dissected arteries met the inclusion criteria. The mean age of the 179 patients with sCAD was 49.5 years, 78% were male, and 18 patients (10%) had bilateral sCAD. According to our classification, there were 56 type Ⅰ (28.4%), 50 type Ⅱ (25.4%), 60 type Ⅲ (30.5%), and 31 type Ⅳ (15.7%) dissections. During a mean hospitalization length of 11.4 ± 47.0 days, there were nine recurrent strokes (4.6%) after medical treatment, two type Ⅲ dissections (1.0%), seven type Ⅳ dissections (3.6%), all ipsilateral, and one death. Overall, there were seven (3.6%, 1 type Ⅰ dissection, 3 type Ⅱ dissections, 2 type Ⅲ dissections, and 1 type Ⅳ dissection) recurrent strokes and three (1.5%, all type Ⅲ dissections) recurrent transient ischemic attacks in patients treated with just medical therapy during the follow-up period, all ipsilateral, with a mean follow-up of 26 months (range, 3-59 months). These patients did not undergo further intervention due to the high difficulty associated with endovascular treatment (EVT) or the mild nature of recurrent cerebral ischemic symptoms. Twenty-nine type I dissections (51.8%) were completely recanalized after antithrombotic therapy. A total of 19 type II dissections (38%) and 44 type III dissections (73%) received EVT for persistent flow-limited dissections, enlargement of dissecting aneurysms, or aggravation of neurological symptoms despite antithrombotic therapy. Type Ⅳ dissections are more likely to lead to the occurrence of ischemic stroke and presented with more severe symptoms. Eight type IVB dissections (33%) received acute phase intervention due to distal thromboembolism or aggravation of neurological symptoms after medical treatment. In terms of cerebral ischemic events and mortality, there were no statistically significant differences among the four types of sCAD (all P > .05). Favorable outcome was achieved in 168 patients (93.9%). CONCLUSIONS: This study proposed a novel and more comprehensive classification method and the modern management strategy for sCAD. Antithrombotic therapy is beneficial to reduce the risk of recurrent stroke for stable sCAD. Non-emergent EVT can be an alternative therapeutic approach for patients who meet indications as in type II to IVA dissections. Urgent procedure with neurovascular intervention is necessary for some type IVB dissections. The short-term results of EVT for sCAD are encouraging, and long-term device-related and functional outcomes should undergo further research.

14.
Insect Mol Biol ; 33(3): 259-269, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38335442

RESUMO

The RNA interference pathway mediated by microRNAs (miRNAs) is one of the methods to defend against viruses in insects. Recent studies showed that miRNAs participate in viral infection by binding to target genes to regulate their expression. Here, we found that the Bombyx mori miRNA, miR-6498-5p was down-regulated, whereas its predicted target gene pyridoxal phosphate phosphatase PHOSPHO2 (BmPLPP2) was up-regulated upon Bombyx mori nucleopolyhedrovirus (BmNPV) infection. Both in vivo and in vitro experiments showed that miR-6498-5p targets BmPLPP2 and suppresses its expression. Furthermore, we found miR-6498-5p inhibits BmNPV genomic DNA (gDNA) replication, whereas BmPLPP2 promotes BmNPV gDNA replication. As a pyridoxal phosphate (PLP) phosphatase (PLPP), the overexpression of BmPLPP2 results in a reduction of PLP content, whereas the knockdown of BmPLPP2 leads to an increase in PLP content. In addition, exogenous PLP suppresses the replication of BmNPV gDNA; in contrast, the PLP inhibitor 4-deoxypyridoxine facilitates BmNPV gDNA replication. Taken together, we concluded that miR-6498-5p has a potential anti-BmNPV role by down-regulating BmPLPP2 to modulate PLP content, but BmNPV induces miR-6498-5p down-regulation to promote its proliferation. Our findings provide valuable insights into the role of host miRNA in B. mori-BmNPV interaction. Furthermore, the identification of the antiviral molecule PLP offers a novel perspective on strategies for preventing and managing viral infection in sericulture.


Assuntos
Bombyx , MicroRNAs , Nucleopoliedrovírus , Animais , Bombyx/virologia , Bombyx/genética , Bombyx/metabolismo , Regulação para Baixo , Proteínas de Insetos/metabolismo , Proteínas de Insetos/genética , Larva/metabolismo , Larva/virologia , Larva/genética , Larva/crescimento & desenvolvimento , MicroRNAs/metabolismo , MicroRNAs/genética , Nucleopoliedrovírus/fisiologia , Fosfato de Piridoxal/metabolismo , Replicação Viral
15.
Diabetes Obes Metab ; 26(6): 2257-2266, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38497233

RESUMO

AIM: Non-alcoholic fatty liver is the most common cause of chronic liver disease. GPR40 is a potential therapeutic target for energy metabolic disorders. GPR40 is a potential therapeutic target for energy metabolic disorders. SZZ15-11 is a newly synthesized GPR40 agonist. In this study, we estimate the potency of SZZ15-11 in fatty liver treatment. METHODS: In vivo, diet-induced obese (DIO) mice received SZZ15-11 (50 mg/kg) and TAK875 (50 mg/kg) for 6 weeks. Blood glucose and lipid, hepatocyte lipid and liver morphology were analysed. In vitro, HepG2 cells and GPR40-knockdown HepG2 cells induced with 0.3 mM oleic acid were treated with SZZ15-11. Triglyceride and total cholesterol of cells were measured. At the same time, the AMPK pathway regulating triglycerides and cholesterol esters synthesis was investigated via western blot and quantitative polymerase chain reaction in both liver tissue and HepG2 cells. RESULTS: SZZ15-11 was found to not only attenuate hyperglycaemia and hyperlipidaemia but also ameliorate fatty liver disease in DIO mice. At the same time, SZZ15-11 decreased triglyceride and total cholesterol content in HepG2 cells. Whether examined in the liver of DIO mice or in HepG2 cells, SZZ15-11 upregulated AMPKα phosphorylation and then downregulated the expression of the cholesterogenic key enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase and inhibited acetyl-CoA carboxylase activity. Furthermore, SZZ15-11 promotes AMPK activity via [cAMP]i accumulation. CONCLUSION: This study confirmed that SZZ15-11, a novel GPR40 agonist, improves hyperlipidaemia and fatty liver, partially via Gs signalling and the AMPK pathway in hepatocytes.


Assuntos
Proteínas Quinases Ativadas por AMP , Homeostase , Hepatopatia Gordurosa não Alcoólica , Obesidade , Receptores Acoplados a Proteínas G , Transdução de Sinais , Animais , Humanos , Masculino , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Dieta Hiperlipídica , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triglicerídeos/metabolismo
16.
Nature ; 562(7726): 249-253, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30305742

RESUMO

Light-emitting diodes (LEDs), which convert electricity to light, are widely used in modern society-for example, in lighting, flat-panel displays, medical devices and many other situations. Generally, the efficiency of LEDs is limited by nonradiative recombination (whereby charge carriers recombine without releasing photons) and light trapping1-3. In planar LEDs, such as organic LEDs, around 70 to 80 per cent of the light generated from the emitters is trapped in the device4,5, leaving considerable opportunity for improvements in efficiency. Many methods, including the use of diffraction gratings, low-index grids and buckling patterns, have been used to extract the light trapped in LEDs6-9. However, these methods usually involve complicated fabrication processes and can distort the light-output spectrum and directionality6,7. Here we demonstrate efficient and high-brightness electroluminescence from solution-processed perovskites that spontaneously form submicrometre-scale structures, which can efficiently extract light from the device and retain wavelength- and viewing-angle-independent electroluminescence. These perovskites are formed simply by introducing amino-acid additives into the perovskite precursor solutions. Moreover, the additives can effectively passivate perovskite surface defects and reduce nonradiative recombination. Perovskite LEDs with a peak external quantum efficiency of 20.7 per cent (at a current density of 18 milliamperes per square centimetre) and an energy-conversion efficiency of 12 per cent (at a high current density of 100 milliamperes per square centimetre) can be achieved-values that approach those of the best-performing organic LEDs.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38845151

RESUMO

Cellulases play an important role in the bioconversion of lignocellulose. Microorganisms found in extreme environments are a potentially rich source of cellulases with unique properties. Due to the uniqueness of the environment, the abundant microbial resources in the Qinghai-Tibet Plateau (QTP) are worth being explored. The aim of this study was to isolate and characterize an acidic, mesophilic cellulase-producing microorganism from QTP. Moreover, the fermentation conditions for cellulase production were optimized for future application of cellulase in the development of lignocellulose biomass. A novel cellulase-producing strain, Penicillium oxalicum XC10, was isolated from the soil of QTP. The cellulase produced by XC10 was a mesophilic cellulase that exhibited good acid resistance and some cold-adaptation properties, with maximum activity at pH 4.0 and 40°C. Cellulase activity was significantly enhanced by Na+ (p < 0.05) and inhibited by Mg2+, Ca2+, Cu2+, and Fe3+ (p < 0.05). After optimization, maximum cellulase activity (8.56 U/mL) was increased nearly 10-fold. Optimal fermentation conditions included an inoculum size of 3% (v/v) in a mixture of corn straw (40 g/L), peptone (5 g/L), and Mg2+ (4 g/L), at pH 4.0, 33°C, and shaking at 200 rpm. The specific properties of the P. oxalicum XC10 cellulase suggest the enzyme may serve as an excellent candidate for the bioconversion and utilization of lignocellulose biomass generated as agricultural and food-processing wastes.

18.
Cell Biochem Funct ; 42(4): e4078, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38898665

RESUMO

Zinc finger proteins (ZNFs) play a significant role in the initiation and progression of tumors. Nevertheless, the specific contribution of ZNF610 to lung adenocarcinoma (LUAD) remains poorly understood. This study sought is to elucidate the role of ZNF610 in LUAD. Transcript data of LUAD were obtained from The Cancer Genome Atlas Program (TCGA) database and processed via R program. The expression of ZNF610 was assessed in various cell lines. To compare the proliferative capacity of cells with or without ZNF610 silencing, CCK8, cell colony formation assay, and Celigo label-free cell counting assay were employed. Furthermore, transwell migration and invasion assays were conducted to evaluate the migratory and invasive abilities of the cells. The expression levels of genes and proteins were assessed using quantitative real-time polymerase chain reaction (qRT-PCR) and western blot techniques. In different LUAD cells, the expression level of ZNF610 was found to be significantly higher in LUAD cells compared to MRC-5 and BASE-2B cells. Moreover, the silencing of ZNF610 resulted in a decrease in cell proliferation and migration abilities. Additionally, the apoptosis rate of cells increased upon silencing ZNF610. Notably, the proportion of cells in the G0/G1 phase increased, while the proportion of cells in the S phase decreased following ZNF610 silencing. Finally, ß-catenin and snail were identified as downstream targets of ZNF610 in cells. Our findings suggest that silencing ZNF610 could inhibit LUAD cell proliferation and migration, possibly through the downregulation of ß-catenin and snail.


Assuntos
Adenocarcinoma de Pulmão , Movimento Celular , Proliferação de Células , Neoplasias Pulmonares , Humanos , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Inativação Gênica , Linhagem Celular Tumoral , Apoptose
19.
J Sep Sci ; 47(11): e2400127, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38819762

RESUMO

Hua-ju-hong (HJH) is a Chinese medicinal material obtained from Citrus grandis 'Tomentosa' (CGT) and Citrus grandis (L.) Osbeck (CG) with various commercial specifications. It is known for relieving cough and dispelling phlegm. To reveal the quality marker for distinguishing the various HJH, 215 batches of commercial HJH were studied systematically using multidimensional chemical analysis. Ten major components were identified by high-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry and quantified via high-performance liquid chromatography coupled with diode array detection. In this study, a rapid, efficient, and low-cost chromatographic method was established. Total coumarin-hemiterpene and total coumarin-monoterpene were first classified and analyzed in HJH. The result indicated that the main component, naringin, was not the quality marker for differentiating CGT from CG. For reflecting the unique medicinal and food value of HJH, coumarins should be the more potential quality markers. Flavonoids were the possible quality markers for distinguishing two growth stages of fruit-exocarp and young fruit. For the first time, two chemotypes of HJH were identified in CG. This study provides a convenient yet reliant chromatographic method and novel yet systematic strategies for overall quality control of commercial HJH.


Assuntos
Citrus , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Citrus/química , Cumarínicos/análise , Cumarínicos/química , Espectrometria de Massas , Controle de Qualidade , Estrutura Molecular
20.
Lipids Health Dis ; 23(1): 88, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528544

RESUMO

The accumulation of reactive oxygen species (ROS) within the bone marrow microenvironment leads to diminished osteogenic differentiation and heightened lipogenic differentiation of mesenchymal stem cells residing in the bone marrow, ultimately playing a role in the development of osteoporosis (OP). Mitigating ROS levels is a promising approach to counteracting OP. In this study, a nanozyme composed of magnesium-based zeolitic imidazolate frameworks (Mg-ZIF) was engineered to effectively scavenge ROS and alleviate OP. The results of this study indicate that Mg-ZIF exhibits significant potential in scavenging ROS and effectively promoting osteogenic differentiation of bone mesenchymal stem cells (BMSCs). Additionally, Mg-ZIF was found to inhibit the differentiation of BMSCs into adipose cells. In vivo experiments further confirmed the ability of Mg-ZIF to mitigate OP by reducing ROS levels. Mechanistically, Mg-ZIF enhances the differentiation of BMSCs into osteoblasts by upregulating lipid metabolic pathways through ROS scavenging. The results indicate that Mg-ZIF has potential as an effective therapeutic approach for the treatment of osteoporosis.


Assuntos
Células-Tronco Mesenquimais , Osteoporose , Humanos , Osteogênese/genética , Magnésio , Metabolismo dos Lipídeos/genética , Espécies Reativas de Oxigênio/metabolismo , Células Cultivadas , Diferenciação Celular , Osteoporose/tratamento farmacológico , Osteoporose/genética , Osteoporose/metabolismo , Células da Medula Óssea
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