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1.
Small ; 20(17): e2307955, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38148312

RESUMO

Unraveling the intricacies between oxygen dynamics and cellular processes in the tumor microenvironment (TME) hinges upon precise monitoring of intracellular and intratumoral oxygen levels, which holds paramount significance. The majority of these reported oxygen nanoprobes suffer compromised lifetime and quantum yield when exposed to the robust ROS activities prevalent in TME, limiting their prolonged in vitro usability. Herein, the ruthenium-embedded oxygen nano polymeric sensor (Ru-ONPS) is proposed for precise oxygen gradient monitoring within the cellular environment and TME. Ru-ONPS (≈64±7 nm) incorporates [Ru(dpp)3]Cl2 dye into F-127 and crosslinks it with urea and paraformaldehyde, ensuring a prolonged lifetime (5.4 µs), high quantum yield (66.65 ± 2.43% in N2 and 49.80 ± 3.14% in O2), superior photostability (>30 min), and excellent stability in diverse environmental conditions. Based on the Stern-Volmer plot, the Ru-ONPS shows complete linearity for a wide dynamic range (0-23 mg L-1), with a detection limit of 10 µg mL-1. Confocal imaging reveals Ru-ONPS cellular uptake and intratumoral distribution. After 72 h, HCT-8 cells show 5.20±1.03% oxygen levels, while NIH3T3 cells have 7.07±1.90%. Co-culture spheroids display declining oxygen levels of 17.90±0.88%, 10.90±0.88%, and 5.10±1.18%, at 48, 120, and 216 h, respectively. Ru-ONPS advances cellular oxygen measurement and facilitates hypoxia-dependent metastatic research and therapeutic target identification.


Assuntos
Oxigênio , Polímeros , Oxigênio/metabolismo , Humanos , Polímeros/química , Microambiente Tumoral , Linhagem Celular Tumoral , Animais , Rutênio/química , Camundongos , Técnicas Biossensoriais/métodos , Espaço Intracelular/metabolismo
2.
Cogn Emot ; 28(5): 834-44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24237485

RESUMO

Cognitive flexibility is proposed to be one of the factors underlying how positive emotions can improve creativity. However, previous works have seldom set up or empirically measured an independent index to demonstrate its mediating effect, nor have they investigated its mediating role on different types of creative performances, which involve distinct processes. In this study, 120 participants were randomly assigned to positive, neutral or negative affect conditions. Their levels of cognitive flexibility were then measured by a switch task. Finally, their creative performances were calibrated by either an open-ended divergent thinking test or a closed-ended insight problem-solving task. The results showed that positive emotional states could reduce switch costs and enhance both types of creative performances. However, cognitive flexibility exhibited a full mediating effect only on the relationship between positive emotion and insight problem solving, but not between positive emotion and divergent thinking. Divergent thinking was instead more associated with arousal level. These results suggest that emotions might influence different creative performances through distinct mechanisms.


Assuntos
Cognição/fisiologia , Criatividade , Emoções/fisiologia , Resolução de Problemas/fisiologia , Adulto , Feminino , Humanos , Masculino , Estudantes/psicologia , Análise e Desempenho de Tarefas , Adulto Jovem
3.
Chem Commun (Camb) ; 60(46): 5948-5951, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38764410

RESUMO

Structurally symmetric dyes using functionalized fluorenes and benzotriazole as the main building moieties have been synthesized and found to exhibit efficient dual-state emission (DSE) and interesting two-wavelength or dual amplified spontaneous emission (dual-ASE) behaviors in the solution phase, which may benefit the development of organic gain materials with dual-wavelength amplification.

4.
Eur J Pharmacol ; 939: 175437, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36502961

RESUMO

Pimavanserin is a highly selective 5-HT2A inverse agonist in current medical use. Prior studies suggest that 5-HT2A serotonin receptors may play a role in anxiety and emotional memory. Therefore, pimavanserin was tested in a rat model of PTSD to determine whether it might ameliorate PTSD-like symptoms. The lifetime prevalence of PTSD is estimated to be 125% higher in women than men. Consequently, in an effort to create a robust model of PTSD that was more representative of human PTSD prevalence, 20-week old female rats of the emotionally hyperreactive Lewis strain were used for these studies. The rats were single-housed and exposed twice to restraint stress coupled with predator odor or to a sham-stressed condition. Twenty days after the second stress or sham-stress exposure, rats were injected with saline alone or with 0.3 or 1.0 mg/kg pimavanserin, doses that were confirmed to substantially block 5-HT2A receptor activity in this study without causing any non-specific behavioral or adverse effects. One hour later, rats were tested for anxiety through acoustic startle response, the elevated plus-maze and three parameters of open field behavior. Five days later, blood was sampled for plasma corticosterone. The stressed/saline-injected rats had higher anxiety scores and corticosterone levels than sham-stressed/saline-injected rats. Pimavanserin significantly and generally dose-dependently reversed these persistent stress effects, but had no significant effect on the behavioral measures in normal, non-stressed rats. These results, consistent with a role for the 5-HT2A receptor, suggest that pimavanserin might have potential to reduce some consequences of traumatic stress.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Animais , Feminino , Humanos , Masculino , Ratos , Ansiedade/tratamento farmacológico , Ansiedade/etiologia , Corticosterona/farmacologia , Modelos Animais de Doenças , Agonismo Inverso de Drogas , Ratos Endogâmicos Lew , Receptor 5-HT2A de Serotonina , Reflexo de Sobressalto , Serotonina/farmacologia , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Transtornos de Estresse Pós-Traumáticos/etiologia , Estresse Psicológico/complicações , Estresse Psicológico/tratamento farmacológico
5.
3D Print Addit Manuf ; 9(3): 177-188, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36655203

RESUMO

Embedded in a long tradition of craftsmanship, inside or outside building surfaces, is often treated with plaster, which plays both functional and ornamental roles. Today, plasterwork is predominantly produced through rationalized, time-, and cost-efficient processes, used for standardized building elements. These processes have also gained interest in the construction robotics field, and while such approaches target the direct automation of standardized plasterwork, they estrange themselves from the inherent qualities of this malleable material that are well known from the past. This research investigates the design potentials of robotic plaster spraying, proposing an adaptive, thin-layer vertical printing method for plasterwork that aims to introduce a digital craft through additive manufacturing. The presented work is an explorative study of a digitally controlled process that can be applied to broaden the design possibilities for the surfaces of building structures. It involves the spraying of multiple thin layers of plaster onto a vertical surface to create volumetric formations or patterns, without the use of any formwork or support structures. This article describes the experimental setup and the initial results of the data collection method involving systematic studies with physical testing, allowing to develop means to predict and visualize the complex-to-simulate material behavior, which might eventually enable to design with the plasticity of this material in a digital design tool.

6.
Neurosci Lett ; 713: 134524, 2019 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-31585211

RESUMO

Previous work has shown that chronic nicotine administration causes adaptive changes in 5-HT2A receptor expression. Based on this relationship, it was hypothesized that inactivating 5-HT2A receptors with the inverse agonists pimavanserin and volinanserin (MDL100907), would reduce the symptoms of nicotine withdrawal syndrome. Sprague-Dawley rats were rendered nicotine-dependent by subcutaneous infusion of nicotine bitartrate, 9 mg/kg/day for seven days. The infusions were then terminated, and 22 h later, rats were observed under "blind" conditions for somatically expressed behavioral nicotine withdrawal signs. One hour before observations, the nicotine dependent rats were injected i.p. with saline alone, or either 0.3 or 1.0 mg/kg pimavanserin in saline. Total withdrawal signs were reduced in a dose-dependent manner. A one-way ANOVA (total withdrawal signs as a function of dose) was highly significant, as was the descending linear trend of withdrawal signs as a function of dose. The 1.0 mg/kg dose reduced withdrawal signs nearly to the level exhibited by a comparison group of non-dependent rats injected with saline. A second experiment was conducted in a similar manner, which showed that volinanserin at 1.0 mg/kg but not 0.25 mg/kg also reduced nicotine withdrawal signs to nearly the level of non-dependent rats. In vitro experiments demonstrated that both pimavanserin and volinanserin potently antagonize 5-HT2A receptors, with approximately 25-fold, and 300-fold selectivity over 5-HT2C receptors, respectively. The results suggest that the 5-HT2A receptor contributes to mediating nicotine withdrawal syndrome, and thus represents a potential target for interventions to aid smoking cessation.


Assuntos
Fluorbenzenos/farmacologia , Nicotina/efeitos adversos , Piperidinas/farmacologia , Receptor 5-HT2A de Serotonina/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/prevenção & controle , Ureia/análogos & derivados , Animais , Relação Dose-Resposta a Droga , Agonismo Inverso de Drogas , Masculino , Ratos , Receptor 5-HT2C de Serotonina/efeitos dos fármacos , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Ureia/farmacologia
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