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1.
Proc Natl Acad Sci U S A ; 120(31): e2301364120, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37487078

RESUMO

In nearly all cases of underwater adhesion, water molecules typically act as a destroyer. Thus, removing interfacial water from the substrate surfaces is essential for forming super-strong underwater adhesion. However, current methods mainly rely on physical means to dislodge interfacial water, such as absorption, hydrophobic repulsion, or extrusion, which are inefficient in removing obstinate hydrated water at contact interface, resulting in poor adhesion. Herein, we present a unique means of reversing the role of water to assist in realizing a self-strengthening liquid underwater adhesive (SLU-adhesive) that can effectively remove water at contact interface. This is achieved through multiscale physical-chemical coupling methods across millimeter to molecular levels and self-adaptive strengthening of the cohesion during underwater operations. As a result, strong adhesion over 1,600 kPa (compared to ~100 to 1,000 kPa in current state of the art) can be achieved on various materials, including inorganic metal and organic plastic materials, without preloading in different environments such as pure water, a wide range of pH solutions (pH = 3 to 11), and seawater. Intriguingly, SLU-adhesive/photothermal nanoparticles (carbon nanotubes) hybrid materials can significantly reduce the time required for complete curing from 24 h to 40 min using near-infrared laser radiation due to unique thermal-response of the chemical reaction rate. The excellent adhesion property and self-adaptive adhesion procedure allow SLU-adhesive materials to demonstrate great potential for broad applications in underwater sand stabilization, underwater repair, and even adhesion failure detection as a self-reporting adhesive. This concept of "water helper" has potential to advance underwater adhesion and manufacturing strategies.

2.
Proc Natl Acad Sci U S A ; 117(21): 11240-11246, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32393646

RESUMO

Ice accumulation causes various problems in our daily life for human society. The daunting challenges in ice prevention and removal call for novel efficient antiicing strategies. Recently, photothermal materials have gained attention for creating icephobic surfaces owing to their merits of energy conservation and environmental friendliness. However, it is always challenging to get an ideal photothermal material which is cheap, easily fabricating, and highly photothermally efficient. Here, we demonstrate a low-cost, high-efficiency superhydrophobic photothermal surface, uniquely based on inexpensive commonly seen candle soot. It consists of three components: candle soot, silica shell, and polydimethylsiloxane (PDMS) brushes. The candle soot provides hierarchical nano/microstructures and photothermal ability, the silica shell strengthens the hierarchical candle soot, and the grafted low-surface-energy PDMS brushes endow the surface with superhydrophobicity. Upon illumination under 1 sun, the surface temperature can increase by 53 °C, so that no ice can form at an environmental temperature as low as -50 °C and it can also rapidly melt the accumulated frost and ice in 300 s. The superhydrophobicity enables the melted water to slide away immediately, leaving a clean and dry surface. The surface can also self-clean, which further enhances its effectiveness by removing dust and other contaminants which absorb and scatter sunlight. In addition, after oxygen plasma treatment, the surface can restore superhydrophobicity with sunlight illumination. The presented icephobic surface shows great potential and broad impacts owing to its inexpensive component materials, simplicity, ecofriendliness, and high energy efficiency.

3.
Sensors (Basel) ; 23(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37960543

RESUMO

The rapid detection of distracted driving behaviors is crucial for enhancing road safety and preventing traffic accidents. Compared with the traditional methods of distracted-driving-behavior detection, the YOLOv8 model has been proven to possess powerful capabilities, enabling it to perceive global information more swiftly. Currently, the successful application of GhostConv in edge computing and embedded systems further validates the advantages of lightweight design in real-time detection using large models. Effectively integrating lightweight strategies into YOLOv8 models and reducing their impact on model performance has become a focal point in the field of real-time distracted driving detection based on deep learning. Inspired by GhostConv, this paper presents an innovative GhostC2f design, aiming to integrate the idea of linear transformation to generate more feature maps without additional computation into YOLOv8 for real-time distracted-driving-detection tasks. The goal is to reduce model parameters and computational load. Additionally, enhancements have been made to the path aggregation network (PAN) to amplify multi-level feature fusion and contextual information propagation. Furthermore, simple attention mechanisms (SimAMs) are introduced to perform self-normalization on each feature map, emphasizing feature maps with valuable information and suppressing redundant information interference in complex backgrounds. Lastly, the nine distinct distracted driving types in the publicly available SFDDD dataset were expanded to 14 categories, and nighttime scenarios were introduced. The results indicate a 5.1% improvement in model accuracy, with model weight size and computational load reduced by 36.7% and 34.6%, respectively. During 30 real vehicle tests, the distracted-driving-detection accuracy reached 91.9% during daylight and 90.3% at night, affirming the exceptional performance of the proposed model in assisting distracted driving detection when driving and contributing to accident-risk reduction.

4.
Dev Neurosci ; 44(3): 153-161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35203077

RESUMO

BACKGROUND: Sevoflurane is a volatile anesthetic that is widely used in pediatric anesthesia due to its low toxicity. However, whether neonatal exposure to sevoflurane induces long-lasting cognitive impairment remains unclear. It has been reported that neuronal injury is the main cause of sevoflurane-induced learning and memory disabilities in the development of brain. But, the specific mechanism is not well elucidated. The injury of synapse occurs earlier than that of neuronal cell in brain injury. The synaptic plasticity is involved in learning and memory. METHODS: We compared the learning and memory ability of neonatal mice to sevoflurane for once or three times in vitro and synaptic plasticity as well as neuronal excitability in vivo. In this study, neonatal C57BL/6J mice were exposed to 3% sevoflurane for 2 h on postnatal day 7 (P7) or once daily for 3 consecutive days (P7/8/9). The Morris water maze test was performed to evaluate the cognitive performance on P31 and P61, respectively. Theta burst stimulation-induced long-term potentiation (LTP) was measured in acute hippocampal slices from P38 and P68 mice to assess the synaptic plasticity. Primary hippocampal neurons were isolated from 24-h-old mice and exposed to different doses of sevoflurane (1, 2, and 3 minimum alveolar anesthetic concentration [MAC]) for 6 h to examine the neuronal excitability. RESULTS: The results showed that compared with the control, repeated exposure to sevoflurane resulted in significant cognitive impairment in adolescent mice, while showing no effect on adult mice. Repeated exposure to sevoflurane remarkably attenuated hippocampal LTP of adolescent mice, which turned to normal in adult mice. No significant difference of LTP was observed between control mice and one-dose sevoflurane-treated mice both in adolescent and adult mice. In primary hippocampal neurons, 2 MAC and 3 MAC sevoflurane delayed neuronal excitation and dose-dependently reduced the number of evoked action potentials compared with control. These effects disappeared after a 24-h recovery. CONCLUSIONS: These data suggested that sevoflurane may impair cognitive performance and neuronal plasticity when administered repeatedly or in a high MAC during infancy, which is noticeable during adolescence but alleviates during adulthood.


Assuntos
Hipocampo , Plasticidade Neuronal , Adulto , Animais , Animais Recém-Nascidos , Cognição , Humanos , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Sevoflurano/toxicidade
5.
Small ; 16(11): e1907468, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32068961

RESUMO

Advanced functional materials enable lithium-ion batteries to reach high specific capacity. To achieve this goal, nickel foam (NF), as current collector, is chosen to in situ form aligned nanoarrays composed of CoP3 /carbon polyhedron (CP)/CoO. The CoO nanowire acts as bridge to link NF and CoP3 /CP which not only reinforces the adhesion between active material and NF but also enhances the capacity of whole electrode. Besides, CoP3 is evenly coupled with CP, which can effectively buffer the volume expansion of CoP3 during the charge/discharge process. Moreover, the novel architecture of CoP3 /CP/CoO/NF is beneficial to improve the electronic conductivity. As a result, the CoP3 /CP/CoO/NF anode delivers an ultrahigh specific capacity of 1715 mAh g-1 at 0.5 A g-1 which can remain at 1150 mAh g-1 after 80 cycles, demonstrating the good durability. Thus, this work develops a facile strategy to design self-supporting electrodes for an enhanced energy storage device.

6.
Nanotechnology ; 31(9): 095402, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31715593

RESUMO

In this work we propose a facile template-sacrificing method to prepare bowl-like silicon@reduced graphene oxide (Si@rGO) hybrids as a high-performance anode for lithium ion batteries (LIBs). Uniform SiO2 spheres were initially synthesized and wrapped by GO, forming a three-dimensional (3D) skeleton. After reduction and etching, Si nanoparticles were obtained and evenly distributed on the flexible rGO layer, resulting in a bowl-like nanoarchitecture. A benefit of this novel structure is that the volume change of Si can be confined during the charge-discharge process. As a result, the Si@rGO anode exhibited a high first discharge capacity of ∼1890 mAh  g-1 with a Coulombic efficiency of 90.79% at a current density of 0.1 A  g-1. After 100 cycles, a stable specific capacity of 450 mAh  g-1 was achieved, which is twice that of pure Si nanospheres (208 mAh  g-1) and rGO (260 mAh  g-1). Moreover, when the current density increased to 1 A g-1, the specific capacity of Si@rGO was 100 mAh  g-1, whereas it was 34 mAh  g-1 for Si nanospheres, demonstrating the advantage of Si@rGO. By analyzing the electrochemical behavior, it is found that the outstanding LIB performance of Si@rGO can be ascribed to the involvement of rGO which constructs the 3D nanoarchitecture that acts as a buffer layer to stabilize the Si and promotes Li+ diffusion as well as the conductivity of the electrodes. This work highlights the significance of the microstructure for lithium ion storage performance of Si-based nanocomposites.

7.
BMC Anesthesiol ; 20(1): 135, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32487137

RESUMO

BACKGROUND: There is very little published literature and none that discussed care in a neonate regarding anesthetic risk and management of neonate with congenital bronchobiliary fistula during thoracoscopy and thoracotomy. This article analyzes related risk factors and literature review from perioperative ventilation, circulation and other aspects of management. CASE PRESENTATION: A neonate diagnosed as congenital bronchobiliary fistula combined with severe chemical pneumonia, consolidation of the lungs, and infection was facing the risk of anaesthesia under thoracoscopy exploration surgery, who experiened more than 20 days diagnostic period before operation. Many risk factors have led to conversion from minimally invasive surgery to thoracotomy, including persistent hypoxemia, hypercapnia, difficult surgical exposure and extremly difficulty of intraoperative ventilation management. Anesthesia maintenance after conversion to open access remained problematic. Fortunately the patient showed no sign of any adverse CNS effects after 4 months of follow-up. CONCLUSIONS: The most prominent anesthesia challenges are hypoxemia, increased airway resistance, impaired ventilation, and the risk of metabolic acidosis. Close cooperation among the entire neonatal medical team is the key factors in successful management of this rare case.


Assuntos
Anestesia/métodos , Fístula Biliar/cirurgia , Fístula Brônquica/cirurgia , Fístula Biliar/congênito , Fístula Biliar/diagnóstico por imagem , Fístula Brônquica/congênito , Fístula Brônquica/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido
8.
Nanotechnology ; 31(4): 045402, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604344

RESUMO

In this work, quasi-two-dimensional spinel ZnCo2O4 (ZCO) nanosheets comprising ZCO nanoparticles of different grain size were prepared via a facile solvothermal method and followed by post-treatment. It shows that the ZCO with a small grain size can be obtained by a fast cooling post-treatment. To enhance the conductivity of ZCO, uniform and compact ZCO nanosheets were in situ grown on reduced graphene oxide (rGO), which was employed as the template. When used as an anode for lithium ion batteries (LIBs), rGO@ZCO has a highly reversible capacity of 1107.2 mAh · g-1 at 100 mA · g-1 after 100 cycles, which is the highest among all ZCO samples. Moreover, when the current density is from 50 to 500 mA · g-1, the capacity of rGO@ZCO decreased from 1046.5 to 527.6 mAh · g-1, implying superior rate ability. The electrochemical analysis, together with calculations demonstrates that the unique structure is beneficial to promote charge transport and adapt the volume change in the charge-discharge process, resulting in expected LIB performance.

9.
Nanotechnology ; 30(49): 495403, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31469113

RESUMO

Heteroatom doped carbon nanomaterials are often employed as advanced anodes for lithium ion batteries (LIBs) because of their stable structure, high capacity and low cost. In this work, we proposed a novel strategy to synthesize high density (N, Ni, P) tri-doped echinus-like porous carbon spheres (PCS) by carbonizing a metal-organophosphine framework (MOPF) directly. The MOPF employs riboflavin sodium phosphate (C17H20N4NaO9P) as an organic ligand as well as a nitrogen and phosphorus source to conjugate with Ni(NO3)2 · 6H2O. As an anode for LIBs, PCS was demonstrated with discharge capacities that were able to reach 386.5 mAh · g-1 after 100 cycles at a current density of 0.05 A · g-1. Besides, the stable reversible capacities were obtained from ∼459 mAh · g-1 to ∼91.8 mAh · g-1 when the current density was varied from 0.05 to 1 A · g-1. The good anode performance is attributed to the unique structure of PCS and (N, Ni, P) tri-doping which introduces the additional capacities due to the presence of the 'reservoir effect'. Moreover, the electrochemical analysis implied that the surface-limited capacitive behavior dominantly contributes to the lithium ion storage capacity of the PCS anode.

11.
Proc Natl Acad Sci U S A ; 109(46): 18891-6, 2012 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-23012477

RESUMO

From microbial biofilm communities to multicellular organisms, 3D macroscopic structures develop through poorly understood interplay between cellular processes and mechanical forces. Investigating wrinkled biofilms of Bacillus subtilis, we discovered a pattern of localized cell death that spatially focuses mechanical forces, and thereby initiates wrinkle formation. Deletion of genes implicated in biofilm development, together with mathematical modeling, revealed that ECM production underlies the localization of cell death. Simultaneously with cell death, we quantitatively measured mechanical stiffness and movement in WT and mutant biofilms. Results suggest that localized cell death provides an outlet for lateral compressive forces, thereby promoting vertical mechanical buckling, which subsequently leads to wrinkle formation. Guided by these findings, we were able to generate artificial wrinkle patterns within biofilms. Formation of 3D structures facilitated by cell death may underlie self-organization in other developmental systems, and could enable engineering of macroscopic structures from cell populations.


Assuntos
Bacillus subtilis/fisiologia , Biofilmes/crescimento & desenvolvimento , Deleção de Genes , Genes Bacterianos/fisiologia
12.
J Cardiothorac Vasc Anesth ; 28(3): 682-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24103716

RESUMO

OBJECTIVES: To determine whether remote ischemic preconditioning (RIPC) reduces myocardial injury, mortality, morbidity, and resource utilization in cardiac surgery. DESIGN: Meta-analysis of controlled clinical trials. The primary outcome was cardiac troponin I (cTnI) concentrations. Secondary outcomes included cardiac troponin T (cTnT) concentrations, myocardial infarction, stroke, renal failure requiring hemodialysis, atrial fibrillation, inotropic score, mechanical ventilation time, length of intensive care unit stay, length of hospital stay, and death. SETTING: University hospitals. PATIENTS: Adult and pediatric patients undergoing cardiac surgery, including coronary artery bypass grafting, valve procedures, and correction of congenital cardiac anomalies. INTERVENTIONS: Remote ischemic preconditioning through limb ischemia. MEASUREMENTS AND MAIN RESULTS: Nineteen randomized trials involving 1,235 patients were included in the meta-analysis. The cTnI concentrations at 6 (or 4-8) hours postoperatively and the total cTnI released after surgery showed a statistically significant reduction in the RIPC group compared with a control group (weighted mean difference [WMD] -2.03 ug/L, 95% confidence interval [CI] -3.25 to -0.82 ug/L, p = 0.001; WMD -65.74 ug/L*h, 95% CI -107.88 to -23.61 ug/L*h, p = 0.002, respectively). There were no differences in mortality, morbidity, and resource utilization between groups. CONCLUSIONS: Current evidence suggests that RIPC reduces cardiac troponin I release in patients undergoing cardiac surgery. The clinical significance of these observations merits further investigation.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Precondicionamento Isquêmico Miocárdico/métodos , Troponina I/metabolismo , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
J Cardiothorac Vasc Anesth ; 28(5): 1233-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24447498

RESUMO

OBJECTIVE: Tranexamic acid (TA), a synthetic antifibrinolytic drug, has been shown to reduce postoperative bleeding and the need for allogeneic blood transfusion in cardiac surgery. However, the optimal dose regimen of TA is still under debate. The aim of this study was to evaluate whether a lower-dose TA regimen produced equivalent efficacy to its higher-dose counterpart in reducing postoperative bleeding and transfusion needs. DESIGN: A prospective, randomized, double-blind trial. SETTING: National Center for Cardiovascular Diseases & University Hospital, Beijing, People's Republic of China. PARTICIPANTS: One hundred seventy-five patients undergoing cardiac valve surgery were enrolled in the study. INTERVENTIONS: All patients were divided randomly into 2 groups. The lower-dose TA group received a loading dose of 10 mg/kg, maintenance dose of 2 mg/kg/h, and a cardiopulmonary bypass pump prime dose of 40 mg; the higher-dose TA group received a loading dose of 30 mg/kg, maintenance dose of 16 mg/kg/h, and a pump prime dose of 2 mg/kg. MEASUREMENTS AND MAIN RESULTS: The amount of postoperative bleeding, the amount and frequency of allogeneic transfusion, mortality, and morbidities were recorded. There was no significant difference in the volume of 24-hour postoperative bleeding between the lower-dose group and the higher-dose group. Other measurements also showed no statistical difference between the 2 groups, including the amount and frequency of allogeneic transfusion, mortality, and morbidities. CONCLUSION: Lower-dose TA regimen was as effective as the higher-dose regimen in reducing postoperative bleeding and transfusion needs in patients undergoing cardiac valve surgery.


Assuntos
Antifibrinolíticos/administração & dosagem , Ponte Cardiopulmonar/efeitos adversos , Hemorragia Pós-Operatória/prevenção & controle , Ácido Tranexâmico/administração & dosagem , Adulto , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Hemorragia Pós-Operatória/etiologia , Estudos Prospectivos
14.
J Colloid Interface Sci ; 661: 662-670, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38310772

RESUMO

With the ever-growing demand for high-capacity energy storage technologies, lithium-ion batteries (LIBs) have drawn increasing attention. Ti2B2, a typical two-dimensional MBenes material, has been considered as a strong contender for anode materials of LIBs with significant performance. However, the limited Li storage capacity of MBenes has hindered its wide applications. To address this issue, we have functionalized Janus-structured MBenes, denoted as Ti2B2XaXb (Xa/Xb = N, O, S, Se). Employing first-principles simulations based on density functional theory, we have investigated the geometric characteristics and electrochemical properties of Ti2B2XaXb. Our results reveal that Ti2B2NO exhibits an exceptionally large theoretical specific capacity of 1091.17 mAh·g-1, improved by 2.4 times compared with the pristine Ti2B2 (456 mAh·g-1). Li atoms on the O side of Ti2B2NO possess a low diffusion barrier of 0.33 eV, which is conducive to the rapid charging and discharging of the battery. Moreover, the open-circuit voltage of Ti2B2NO within the safe voltage range of 0-1 V ensures the safety of battery operation. Overall, our study sheds light on understanding the underlying mechanism of surface functionalization on the Li storage properties of Janus-structured MBenes from atomic-scale, laying the groundwork for future design of high-performance anode materials.

15.
Ther Clin Risk Manag ; 20: 207-216, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38524686

RESUMO

Purpose: Despite the implementation of various insulation measures, the incidence of hypothermia during thyroid surgery remains high. This randomized controlled study aimed to evaluate the effects of aggressive thermal management combined with resistive heating mattresses to prevent perioperative hypothermia in patients undergoing thyroid surgery. Patients and Methods: 142 consecutive patients scheduled for elective thyroid surgery were enrolled in the study. They were randomly and equally allocated to the aggressive warming or routine care groups (n = 71). The patients' body temperature was monitored before the induction of anesthesia until they returned to the ward. The primary outcome was the incidence of perioperative hypothermia. Secondary outcomes included postoperative complications, such as mortality, cardiovascular complications, wound infection, shivering, postoperative nausea and vomiting (PONV), visual analog scale (VAS) pain scores, fever, headache and hospital length of stay (LOS). Results: In our study, the results showed that a significantly higher rate of hypothermia was observed in the routine care group compared with the aggressive warming group. The incidence of perioperative hypothermia was 19.72% (14/71) in the aggressive warming group and 35.21% (25/71) in the routine care group (P < 0.05). The incidence of shivering in the aggressive warming group (1.41%) was significantly lower than that in the routine care group (11.27%) (P < 0.05), and a one-day reduction in hospital length of stay was observed in the aggressive warming group (P < 0.05). There was no significant difference in mortality or other postoperative complications, such as cardiovascular complications, wound infection, PONV, pain, fever or headache, between the two groups (P > 0.05). Conclusion: Our results suggest that aggressive thermal management combined with resistive heating mattresses provided improved perioperative body temperature and reduced the incidence of perioperative hypothermia and shivering compared to routine thermal management.


●The incidence of perioperative hypothermia during thyroid surgery was high. ●The use of resistive heating mattresses during thyroid surgery can effectively reduce the occurrence of perioperative hypothermia. ●It is recommended to take aggressive thermal protection during the operation of minor and medium surgeries, and to continuously monitor the temperature.

16.
Ther Clin Risk Manag ; 20: 217-225, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38532744

RESUMO

Purpose: The aim of this study was to determine whether preoperative video distraction reduces the incidence of emergence delirium in preschool children under general anesthesia with sevoflurane. Patients and Methods: In this prospective randomized controlled study, children aged 3-6 years were randomized to receive either video distraction (Group V) or common clinical practice (Group C) from arrival at the holding area to induction of anesthesia. The primary outcome was the incidence of emergence delirium. Preoperative anxiety scores, assessed by the simple modified Yale Perioperative Anxiety Scale, were also collected. Results: A total of 160 patients were included in our study. The children in Group V (n=80) exhibited a significantly lower incidence of emergence delirium than did those in Group C (n=80) (12.5% vs 35.0%; RR 0.36, 95% CI 0.19, 0.69; P =0.0008). The maximum Pediatric Anesthesia Emergence Delirium score in Group V was significantly lower than that in Group C (3.0 vs 5.0; mean difference -2.64, 95% CI: -4.12, -1.16; P=0.0003). The simple modified Yale Perioperative Anxiety Scale scores at separation from parents and the onset of inhalation induction in Group V were significantly lower than those in Group C (36.4 ± 9.9 vs 48.2 ± 16.7; mean difference 11.92, 95% CI 7.25, 16.59; P<0.0001 and 41.5 ± 15.9 vs 59.7 ± 21.5; mean difference 18.11, 95% CI 11.76, 24.47; P<0.0001). Conclusion: Preoperative video distraction reduces the incidence of emergence delirium in preschool children who undergo strabismus surgery under general anesthesia with sevoflurane.

17.
J Psychopharmacol ; 38(5): 489-499, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38680011

RESUMO

BACKGROUND: Psilocybin offers new hope for treating mood disorders due to its rapid and sustained antidepressant effects, as standard medications require weeks or months to exert their effects. However, the mechanisms underlying this action of psilocybin have not been identified. AIMS: To investigate whether psilocybin has rapid and sustained antidepressant-like effects in mice and investigate whether its potential mechanisms of action are related to promoted neuroplasticity. METHODS: We first examined the antidepressant-like effects of psilocybin in normal mice by the forced swimming test and in chronic corticosterone (CORT)-exposed mice by the sucrose preference test and novelty-suppressed feeding test. Furthermore, to explore the role of neuroplasticity in mediating the antidepressant-like effects of psilocybin, we measured structural neuroplasticity and neuroplasticity-associated protein levels in the prefrontal cortex (PFC) and hippocampus. RESULTS: We observed that a single dose of psilocybin had rapid and sustained antidepressant-like effects in both healthy mice and chronic CORT-exposed mice. Moreover, psilocybin ameliorated chronic CORT exposure-induced inhibition of neuroplasticity in the PFC and hippocampus, including by increasing neuroplasticity (total number of dendritic branches and dendritic spine density), synaptic protein (p-GluA1, PSD95 and synapsin-1) levels, BDNF-mTOR signalling pathway activation (BDNF, TrkB and mTOR levels), and promoting neurogenesis (number of DCX-positive cells). CONCLUSIONS: Our results demonstrate that psilocybin elicits robust, rapid and sustained antidepressant-like effects which is accompanied by the promotion of neuroplasticity in the PFC and hippocampus.


Assuntos
Antidepressivos , Fator Neurotrófico Derivado do Encéfalo , Corticosterona , Hipocampo , Plasticidade Neuronal , Córtex Pré-Frontal , Psilocibina , Animais , Plasticidade Neuronal/efeitos dos fármacos , Antidepressivos/farmacologia , Camundongos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Masculino , Psilocibina/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Depressão/tratamento farmacológico , Camundongos Endogâmicos C57BL , Serina-Treonina Quinases TOR/metabolismo , Proteína Duplacortina , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças
18.
Int J Biol Macromol ; 263(Pt 2): 130381, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395291

RESUMO

Enzyme immobilization usually make use of nanomaterials to hold up biocatalysis stability in various unamiable reaction conditions, but also lead large discount on enzyme activity. Thus, there are abundant researches focus on how to deal with the relation of enzyme molecules and supports. In this work, a new state of highly active enzymes has been established through facile and novel in situ immobilization and soft template removal method to construct enzyme contained hollow silica nanosphere (catalase@HSN) biocatalysts where enzymes in the cavity exhibit "immobilized but not rigid state". The obtained catalase@HSN was characterized by transmission electron microscopy, scanning electron microscopy and confocal laser scanning microscopy et al. Catalase@HSN exhibits excellent activity (about 80 % activity recovery rate) and stability suffers from extreme pH, temperature, and organic solvents. Moreover, the reusability and storage stability of catalase@HSN also are satisfactory. This proposed strategy provides a facile method for preparing biocatalysts under mild conditions, facilitating the applications of immobilized enzyme in the fields of real biocatalytic industry with high apparent activity and passable stability.


Assuntos
Nanosferas , Dióxido de Silício , Catalase/metabolismo , Dióxido de Silício/química , Nanosferas/química , Enzimas Imobilizadas/química , Biocatálise , Estabilidade Enzimática
19.
Opt Express ; 21(10): 11808-18, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23736402

RESUMO

Recently, mechanobiology has received increased attention. For investigation of biofilm and cellular tissue, measurements of the surface topography and deformation in real-time are a pre-requisite for understanding the growth mechanisms. In this paper, a novel three-dimensional (3D) fluorescent microscopic method for surface profilometry and deformation measurements is developed. In this technique a pair of cameras are connected to a binocular fluorescent microscope to acquire micrographs from two different viewing angles of a sample surface doped or sprayed with fluorescent microparticles. Digital image correlation technique is used to search for matching points in the pairing fluorescence micrographs. After calibration of the system, the 3D surface topography is reconstructed from the pair of planar images. When the deformed surface topography is compared with undeformed topography using fluorescent microparticles for movement tracking of individual material points, the full field deformation of the surface is determined. The technique is demonstrated on topography measurement of a biofilm, and also on surface deformation measurement of the biofilm during growth. The use of 3D imaging of the fluorescent microparticles eliminates the formation of bright parts in an image caused by specular reflections. The technique is appropriate for non-contact, full-field and real-time 3D surface profilometry and deformation measurements of materials and structures at the microscale.


Assuntos
Biofilmes/crescimento & desenvolvimento , Aumento da Imagem/instrumentação , Imageamento Tridimensional/instrumentação , Microscopia de Fluorescência/instrumentação , Fotogrametria/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
20.
Acta Biochim Pol ; 70(2): 401-405, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37307593

RESUMO

Myocardial fibrosis and inflammation cause cardiac hypertrophy, arrhythmias, and heart failure in diabetics, a leading cause of mortality. Since it's complicated, no drug treats diabetic cardiomyopathy. This research examined the effects of artemisinin and allicin on heart function, myocardial fibrosis, and the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway in diabetic cardiomyopathy rats. A total of 50 rats were separated into 5 groups, 10 of which were the control group. 40 rats received 65 µg/g streptozotocin intraperitoneally. 37 of 40 animals fit the investigation. The artemisinin, allicin, and artemisinin/allicin groups each included nine animals. The artemisinin group received 75 mg/kg of artemisinin, the allicin group received 40 mg/kg of allicin, and the combination group received equal dosages of artemisinin and allicin gavage for four weeks. After the intervention, in each group cardiac functions, myocardial fibrosis, and NF-κB signaling pathway protein expression were assessed. All of the examined groups had greater levels of LVEDD, LVESD, LVEF, FS, E/A, and the NF-κB pathway proteins: NF-κB p65 and p-NF-κB p65 than the normal group, except for the combination group. Artemisinin and allicin did not vary statistically. Compared to the model group, the artemisinin, allicin, and combined groups showed various degrees of improvement from the pathological pattern, with more intact muscle fibers, neater arrangement, more normal cell morphology, artemisinin and allicin alleviated cardiac dysfunction and decreased myocardium fibrosis in diabetic cardiomyopathy rats by inactivating the NF-κB signaling cascade.


Assuntos
Artemisininas , Diabetes Mellitus , Cardiomiopatias Diabéticas , Ratos , Animais , NF-kappa B/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Ratos Sprague-Dawley , Transdução de Sinais , Artemisininas/farmacologia , Fibrose , Diabetes Mellitus/tratamento farmacológico
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