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1.
Plant Cell ; 34(7): 2747-2764, 2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35385118

RESUMO

Many glycine-rich RNA-binding proteins (GR-RBPs) have critical functions in RNA processing and metabolism. Here, we describe a role for the tomato (Solanum lycopersicum) GR-RBP SlRBP1 in regulating mRNA translation. We found that SlRBP1 knockdown mutants (slrbp1) displayed reduced accumulation of total chlorophyll and impaired chloroplast ultrastructure. These phenotypes were accompanied by deregulation of the levels of numerous key transcripts associated with chloroplast functions in slrbp1. Furthermore, native RNA immunoprecipitation-sequencing (nRIP-seq) recovered 61 SlRBP1-associated RNAs, most of which are involved in photosynthesis. SlRBP1 binding to selected target RNAs was validated by nRIP-qPCR. Intriguingly, the accumulation of proteins encoded by SlRBP1-bound transcripts, but not the mRNAs themselves, was reduced in slrbp1 mutants. Polysome profiling followed by RT-qPCR assays indicated that the polysome occupancy of target RNAs was lower in slrbp1 plants than in wild-type. Furthermore, SlRBP1 interacted with the eukaryotic translation initiation factor SleIF4A2. Silencing of SlRBP1 significantly reduced SleIF4A2 binding to SlRBP1-target RNAs. Taking these observations together, we propose that SlRBP1 binds to and channels RNAs onto the SleIF4A2 translation initiation complex and promotes the translation of its target RNAs to regulate chloroplast functions.


Assuntos
Solanum lycopersicum , Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/genética , Fotossíntese/genética , Polirribossomos/metabolismo
2.
Semin Dial ; 37(2): 178-185, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37798864

RESUMO

BACKGROUND: Citrate anticoagulation is an important anticoagulation method in hemodialysis (HD) but cannot completely prevent the occurrence of coagulation in the extracorporeal circulation (ECC) circuit, and the clinical coagulation status can significantly affect the effect of citrate anticoagulation. In this study, the relationships between clinical coagulation status indicators and coagulation in the ECC circuit in HD patients receiving individualized citrate anticoagulant were studied to explore indicators that may predict coagulation in the ECC circuit. METHODS: This study was a single-center, retrospective clinical study, and clinical data and laboratory tests related to the coagulation status of HD patients receiving individualized regional citrate anticoagulation (RCA) were collected. The relationships between indicators commonly used in clinical practice to evaluate clinical coagulation status and coagulation in the ECC circuit were statistically analyzed to find indicators that can predict the occurrence of coagulation in the ECC circuit. RESULTS: The individualized RCA had a good anticoagulation effect, and the actual citrate infusion rate in nearly 80% of the patients was within ±10% of the theoretical infusion rate. The combined diseases or conditions that affect the coagulation status in vivo may increase the incidence of coagulation in the ECC circuit. The clinical D-dimer level is an independent risk factor that affects and can predict coagulation in the ECC circuit, with a cutoff value of 2.03 mg/L, sensitivity of 59%, and specificity of 78%. CONCLUSION: Individualized RCA can meet the needs of most HD treatments. Abnormal coagulation status in HD patients may increase the incidence of coagulation in the ECC circuit during individualized RCA for HD, and the D-dimer level can predict the occurrence of coagulation in the ECC circuit during this treatment.


Assuntos
Ácido Cítrico , Diálise Renal , Humanos , Ácido Cítrico/farmacologia , Ácido Cítrico/uso terapêutico , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Estudos Retrospectivos , Anticoagulantes/uso terapêutico , Citratos/uso terapêutico , Circulação Extracorpórea
3.
J Biochem Mol Toxicol ; 38(10): e23831, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39291620

RESUMO

Helicobacter pylori (HP) is considered a major risk factor for gastric cancer (GC) and during this process, cytotoxin­associated gene A (CagA) plays in essence. The study mainly focused on the molecular mechanism of circular RNA 0046854 (circ_0046854) in HP-induced GC. Clinically, 56 cases of GC and normal tissues were collected, and the GC tissues were divided into HP-negative GC tissues (HP-) and 33 HP-positive GC tissues (HP+). Tissue expression of circ_0046854, microRNA (miR)-511-3p and colony-stimulating factor 1 (CSF1) was tested. BGC-823/Cisplatin (DDP) resistant strain was induced and cell growth and DDP resistance were detected after HP infection. In vivo experiments were performed using a mouse xenograft model. The relationship between circ_0046854, miR-511-3p and CSF1 was confirmed. GC tissues especially HP+ cancer tissues expressed high circ_0046854 and CSF1 and low miR-511-3p. HP-induced circ_0046854 expression in GC cells through CagA. Inhibition of circ_0046854 or miR-511-3p elevation inhibited the growth and DDP resistance in GC cells. Circ_0046854 acted as a sponge for miR-511-3p, which targeted CSF1. Restoring CSF1 could abolish the inhibitory effect of miR-511-3p overexpression on CagA+ HP-induced GC progression in vitro. Circ_0046854 silencing repressed tumor growth and aggrandized the inhibiting effects of DDP on tumorigenesis in vivo. Circ_0046854/miR-511-3p/CSF1 axis may be involved in the development of HP-induced GC, thus providing new ideas for studying the mechanism of HP-related gastric diseases.


Assuntos
Cisplatino , Resistencia a Medicamentos Antineoplásicos , Infecções por Helicobacter , Helicobacter pylori , Fator Estimulador de Colônias de Macrófagos , MicroRNAs , RNA Circular , Neoplasias Gástricas , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/tratamento farmacológico , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Cisplatino/farmacologia , Animais , Fator Estimulador de Colônias de Macrófagos/metabolismo , Fator Estimulador de Colônias de Macrófagos/genética , Camundongos , RNA Circular/genética , RNA Circular/metabolismo , Infecções por Helicobacter/genética , Infecções por Helicobacter/metabolismo , Linhagem Celular Tumoral , Masculino , Feminino , Camundongos Nus , Camundongos Endogâmicos BALB C , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Pessoa de Meia-Idade , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
4.
Psychol Res ; 86(3): 757-768, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34009467

RESUMO

In complex interactive scenarios, action understanding lies at the heart of social interactions. Nevertheless, the ability to understand action intention may differ among people. The current study distinguished two groups of participants with different social intention-understanding abilities (high and low) based on a perspective-taking task to investigate the influence of social intention on object affordance under conditions of individual and cooperative action intention. In the affordance perception experiment, participants were shown a video with the presenter reaching to grasp an object in different grips and asked to classify objects into kitchen or non-kitchen items by pressing the left- or right-hand button under the two intention conditions. The results showed that the object affordance effects were modulated by the participants' understanding of social intention in the interactive scenarios. Specifically, the object affordance effects were observed only in the high perspective-taking ability group under the condition of cooperative action intention. However, under the condition of individual action intention, object affordance effects were shown in both the high and low perspective-taking ability groups, and the difference between the two groups was not significant. This study suggests that processing of object affordance depends greatly on the contextual correspondence of perception and action and that the understanding of cooperative action intention can affect the activation of object affordance.


Assuntos
Intenção , Desempenho Psicomotor , Mãos/fisiologia , Força da Mão , Humanos , Desempenho Psicomotor/fisiologia
5.
Opt Express ; 29(6): 8698-8709, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33820312

RESUMO

In this investigation, we propose a strip segmentation phase (SSP) method for a spatial light modulator (SLM) to generate independent multifocal spots when the beam passes through a high numerical aperture (NA) lens. With the SSP method, multifocal spots can be generated with each spot independently, flexibly and uniformly distributed. The performance of the SSP method is first validated with numerical simulation. Then, by applying the modulation method with SLM and importing the beams into an inverted fluorescence microscopy system with a high-NA lens, the spot distribution and their shapes can be observed by fluorescent image. The fluorescent image exhibits high uniformity and high consistency with the aforementioned numerical simulations. Finally, we dynamically load a series of phase maps on SLM to realize continuous and independent spot movement in a multifocal array. By laser direct writing on photoresist, a complex NWU-shape structure can be realized flexibly with multi-task fabrication capability. The SSP method can significantly improve the efficiency and flexibility of laser direct writing. It is also compatible with most recent techniques, e.g., multiphoton absorption, stimulated emission depletion and photo-induced depolymerization etc., to realize parallel super-resolution imaging and fabrications.

6.
Bull Environ Contam Toxicol ; 102(5): 721-729, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30756128

RESUMO

Mercury contamination in soil and water has become a major concern to environmental quality and human health. Among the existing remediation technologies for mercury pollution control, sorption via iron-based materials has received wide attention as they are environmental friendly and economic, and their reactivity is high and controllable through modulating the morphology and surface properties of particulate materials. This paper aimed to provide a comprehensive overview on environmental application of a variety of iron-based sorbents, namely, zero valent iron, iron oxides, and iron sulfides, for mercury remediation. Techniques to improve the stability of these materials while enhancing mercury sequestration, such as nano-scale size control, surface functionalization, and mechanical support, were summarized. Mechanisms and factors affecting the interaction between mercury and iron-based materials were also discussed. Current knowledge gaps and future research needs are identified to facilitate a better understanding of molecular-level reaction mechanisms between iron-based materials and mercury and the long-term stability of the immobilized mercury.


Assuntos
Recuperação e Remediação Ambiental/métodos , Ferro/química , Mercúrio/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Solo
7.
Conscious Cogn ; 57: 84-93, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29190489

RESUMO

The present study investigated the roles of bottom-up mask-triggered inhibition and top-down inhibition in semantic categorization using the single negative priming (NP) paradigm. The masking (bottom-up) and ignore instructions (top-down, i.e., instructing participants to ignore the primes) were manipulated in Experiments 1-3 and Experiment 4, respectively. No priming was observed when only the masking was manipulated (Experiments 2 and 3), but NP was observed when a possible top-down ignore strategy (Experiment 1) or an ignore instruction (Experiment 4) was added. The results indicate that bottom-up mask-triggered inhibition cannot elicit semantic single NP by itself. However, top-down inhibition from an ignore instruction or ignore strategy is critical for triggering reliable semantic single NP. The findings suggest that semantic single NP originates from a push-pull mechanism by facilitating responses to unrelated trials and inhibiting responses to related trials. The experimental evidence also suggests that unconscious processes can be modulated by top-down control.


Assuntos
Função Executiva/fisiologia , Inibição Psicológica , Reconhecimento Visual de Modelos/fisiologia , Mascaramento Perceptivo/fisiologia , Semântica , Adolescente , Adulto , Estado de Consciência/fisiologia , Feminino , Humanos , Masculino , Leitura , Adulto Jovem
8.
J Environ Sci (China) ; 67: 378-386, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29778171

RESUMO

The importance of enhancing sludge dewaterability is increasing due to the considerable impact of excess sludge volume on disposal costs and on overall sludge management. This study presents an innovative approach to enhance dewaterability of anaerobic digestate (AD) harvested from a wastewater treatment plant. The combination of zero valent iron (ZVI, 0-4.0g/g total solids (TS)) and hydrogen peroxide (HP, 0-90mg/g TS) under pH3.0 significantly enhanced the AD dewaterability. The largest enhancement of AD dewaterability was achieved at 18mg HP/g TS and 2.0g ZVI/g TS, with the capillary suction time reduced by up to 90%. Economic analysis suggested that the proposed HP and ZVI treatment has more economic benefits in comparison with the classical Fenton reaction process. The destruction of extracellular polymeric substances and cells as well as the decrease of particle size were supposed to contribute to the enhanced AD dewaterability by HP+ZVI conditioning.


Assuntos
Peróxido de Hidrogênio/química , Ferro/química , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Esgotos , Águas Residuárias/química
9.
Environ Sci Technol ; 48(7): 3986-94, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24568693

RESUMO

Iron sulfide (FeS) nanoparticles were prepared with sodium carboxymethyl cellulose (CMC) as a stabilizer, and tested for enhanced removal of aqueous mercury (Hg(2+)). CMC at ≥0.03 wt % fully stabilized 0.5 g/L of FeS (i.e., CMC-to-FeS molar ratio ≥0.0006). FTIR spectra suggested that CMC molecules were attached to the nanoparticles through bidentate bridging and hydrogen bonding. Increasing the CMC-to-FeS molar ratio from 0 to 0.0006 enhanced mercury sorption capacity by 20%; yet, increasing the ratio from 0.0010 to 0.0025 diminished the sorption by 14%. FTIR and XRD analyses suggested that precipitation (formation of cinnabar and metacinnabar), ion exchange (formation of Hg0.89Fe0.11S), and surface complexation were important mechanisms for mercury removal. A pseudo-second-order kinetic model was able to interpret the sorption kinetics, whereas a dual-mode isotherm model was proposed to simulate the isotherms, which considers precipitation and adsorption. High mercury uptake was observed over the pH range of 6.5-10.5, whereas significant capacity loss was observed at pH < 6. High concentrations of Cl(-) (>106 mg/L) and organic matter (5 mg/L as TOC) modestly inhibited mercury uptake. The immobilized mercury remained stable when preserved for 2.5 years at pH above neutral.


Assuntos
Carboximetilcelulose Sódica/química , Ferro/química , Mercúrio/química , Nanopartículas/química , Sulfetos/química , Água/química , Adsorção , Cloretos/química , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Cinética , Pós , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo
10.
Environ Sci Technol ; 48(24): 14392-9, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25420231

RESUMO

This work explored the formation mechanism of marine oil snow (MOS) and the associated transport of oil hydrocarbons in the presence of a stereotype oil dispersant, Corexit EC9500A. Roller table experiments were carried out to simulate natural marine processes that lead to formation of marine snow. We found that both oil and the dispersant greatly promoted the formation of MOS, and MOS flocs as large as 1.6-2.1 mm (mean diameter) were developed within 3-6 days. Natural suspended solids and indigenous microorganisms play critical roles in the MOS formation. The addition of oil and the dispersant greatly enhanced the bacterial growth and extracellular polymeric substance (EPS) content, resulting in increased flocculation and formation of MOS. The dispersant not only enhanced dissolution of n-alkanes (C9-C40) from oil slicks into the aqueous phase, but facilitated sorption of more oil components onto MOS. The incorporation of oil droplets in MOS resulted in a two-way (rising and sinking) transport of the MOS particles. More lower-molecular-weight (LMW) n-alkanes (C9-C18) were partitioned in MOS than in the aqueous phase in the presence of the dispersant. The information can aid in our understanding of dispersant effects on MOS formation and oil transport following an oil spill event.


Assuntos
Hidrocarbonetos/química , Lipídeos/química , Poluição por Petróleo , Petróleo , Poluentes Químicos da Água/química , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Biopolímeros/química , Biopolímeros/metabolismo , Floculação
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