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1.
Epilepsy Behav ; 158: 109925, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38959743

RESUMEN

PURPOSE: The effects of levetiracetam (LEV) on bone mineral density (BMD) and bone metabolism are currently inconclusive, and this study was designed to answer this question. METHODS: Citations from PubMed, Embase, Cochrane Library, and Web of Science databases (up to February 4, 2024) were reviewed. The effects of LEV on BMD as well as bone metabolism indicators were measured by calculating the standardized mean difference (SMD) with a 95% confidence interval (CI). This study was registered with PROSPERO (CRD42024509560). RESULTS: A total of 612 individuals from 13 studies were included in the present analysis. Of the items related to bone metabolism, LEV was found to be associated significantly with decreased serum calcium with an SMD of -0.47 (95 % CI, -0.77- -0.16; p = 0.04). However, changes in other markers (including serum phosphorus, 25-hydroxyvitamin D, alkaline phosphatase, and parathyroid hormone) were not statistically significantly correlated with the use of LEV (p > 0.05). Also, when compared to the control groups, the changes in BMD of the observation groups were not significant (p > 0.05). CONCLUSIONS: The use of LEV may significantly reduce serum calcium in patients with epilepsy, and regular monitoring of bone metabolism-related indicators is recommended.


Asunto(s)
Anticonvulsivantes , Densidad Ósea , Epilepsia , Levetiracetam , Levetiracetam/uso terapéutico , Levetiracetam/farmacología , Humanos , Densidad Ósea/efectos de los fármacos , Epilepsia/tratamiento farmacológico , Epilepsia/metabolismo , Anticonvulsivantes/uso terapéutico , Anticonvulsivantes/farmacología , Huesos/efectos de los fármacos , Huesos/metabolismo , Calcio/sangre , Calcio/metabolismo
2.
Micromachines (Basel) ; 15(6)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38930744

RESUMEN

As a novel technology for fabricating large-screen OLED devices, OLED inkjet printing places extreme demands on the positioning accuracy of inkjet printing platforms. However, thermal deformation of the connection mechanism often reduces the printing precision of OLED printing equipment, significantly impacting overall print quality. This study introduces a compliant connection mechanism that achieves precise positioning of the inkjet printing platform and can self-eliminate thermal distortion. The design of the mechanism's core component is based on the Freedom and Constraint Topology (FACT) principle. This component is constructed from three distinct compliant sections arranged in series, collectively providing three degrees of freedom. Furthermore, the resistance to deformation caused by gravity and other external forces was evaluated by analyzing both vertical and horizontal stiffness. To validate the mechanism's thermal distortion elimination and gravity resistance capabilities, finite element analysis (FEA) was carried out. The results demonstrate that the mechanism effectively reduces the maximum deformation of the platform by approximately 46% and the average deformation across the entire platform by approximately 59%. These findings confirm that the mechanism has potential in high-precision positioning tasks that need to mitigate thermal distortion.

3.
Micromachines (Basel) ; 15(5)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38793182

RESUMEN

This article presents the design, analysis, and prototype testing of a four-degrees-of-freedom (4-DoFs) spatial pose adjustment system (SPAS) that achieves high-precision positioning with 4-DoFs (Z/Tip/Tilt/Θ). The system employs a piezoelectric-driven amplification mechanism that combines a bridge lever hybrid amplification mechanism, a double four-bar guide mechanism, and a multi-level lever symmetric rotation mechanism. By integrating these mechanisms, the system achieves low coupling, high stiffness, and wide stroke range. Analytical modeling and finite element analysis are employed to optimize geometric parameters. A prototype is fabricated, and its performance is verified through testing. The results indicate that the Z-direction feed microstroke is 327.37 µm, the yaw motion angle around the X and Y axes is 3.462 mrad, and the rotation motion angle around the Z axis is 12.684 mrad. The x-axis and y-axis motion magnification ratio can reach 7.43. Closed-loop decoupling control experiments for multiple-input-multiple-outputs (MIMO) systems using inverse kinematics and proportional-integral-derivative feedback controllers were conducted. The results show that the Z-direction positioning accuracy is ±100 nm, the X and Y axis yaw motion accuracy is ±2 µrad, and the Z-axis rotation accuracy is ±25 µrad. Due to the ZTTΘ mechanism, the design proved to be feasible and advantageous, demonstrating its potential for precision machining and micro-nano manipulation.

4.
Pharmacol Res ; 161: 105099, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32739427

RESUMEN

As a type of fear relapse, fear renewal compromises the efficacy of fear extinction, which serves as the laboratory analog of exposure therapy (a therapeutic strategy for anxiety disorders). Interventions aiming to prevent fear renewal would thus benefit exposure therapy. To date, it remains unknown whether central adenosine monophosphate (AMP)-activated protein kinase (AMPK) activation could produce inhibitory effects on fear renewal. Here, using pharmacological approach and virus-mediated gene overexpression technique, we demonstrated that activation of AMPK in dorsal hippocampus shortly before fear extinction training completely abolished subsequent fear renewal in male mice without affecting other types of fear relapse, including spontaneous recovery of fear and fear reinstatement. Furthermore, we also found that metformin, a first-line antidiabetic drug, was capable of preventing fear renewal in male mice by stimulating AMPK in dorsal hippocampus. Collectively, our study provides insight into the role of hippocampal AMPK in regulation of fear renewal and indicates that increasing activity of hippocampal AMPK can prevent fear renewal, thus enhancing the potency of exposure therapy.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Conducta Animal/efectos de los fármacos , Activadores de Enzimas/farmacología , Extinción Psicológica , Miedo/efectos de los fármacos , Hipocampo/efectos de los fármacos , Terapia Implosiva , Metformina/farmacología , Proteínas Quinasas Activadas por AMP/genética , Animales , Activación Enzimática , Hipocampo/enzimología , Masculino , Ratones Endogámicos C57BL
5.
Clin Exp Pharmacol Physiol ; 47(1): 95-101, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31494960

RESUMEN

Post-traumatic stress disorder (PTSD) has become a major disease that threatens human health. Neurotransmitters and the amygdala are found to be critical in the development and maintenance of PTSD. We aim to investigate the role of glycyrrhizin in treating PTSD. Contextual fear extinction and elevated plus maze test were applied to evaluate the anxiety and fear memory. Microdialysis and high-performance liquid chromatography were used to analyze the expression of amygdala neurotransmitters in PTSD animal models and to verify the effects of glycyrrhizin on major neurotransmitters. The protein levels of tryptophan hydroxylase 2 (TPH2) were examined by western bolt. Glycyrrhizin treatment significantly reduced anxiety and fear memory after 1 and 7 days of PTSD modelling. In addition, glycyrrhizin treatment restored the circadian rhythm changes of serotonin and TPH2. The present study found a significant circadian rhythm change of serotonin in the amygdala in PTSD rats. Besides, glycyrrhizin treatment restored the altered serotonin diurnal fluctuations, which raises important implications for PTSD treatment.


Asunto(s)
Relojes Circadianos/efectos de los fármacos , Extinción Psicológica/efectos de los fármacos , Ácido Glicirrínico/farmacología , Serotonina/metabolismo , Trastornos por Estrés Postraumático/tratamiento farmacológico , Estrés Psicológico/tratamiento farmacológico , Amígdala del Cerebelo/efectos de los fármacos , Amígdala del Cerebelo/metabolismo , Animales , Ansiedad/metabolismo , Modelos Animales de Enfermedad , Miedo/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Memoria/efectos de los fármacos , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Ratas , Ratas Wistar , Trastornos por Estrés Postraumático/metabolismo , Estrés Psicológico/metabolismo
6.
J Psychopharmacol ; 33(1): 37-50, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30484361

RESUMEN

BACKGROUND AND AIM: Developing fast-acting antidepressants attracts considerable attention. Anemoside A3, a natural triterpenoid glycoside isolated from Pulsatillae Radix, has been reported to produce antidepressant-like action in the forced swim test. We herein explore the fast-onset antidepressant-like potentials and antidepressant mechanisms of anemoside A3. METHODS: The forced swim test and tail suspension test were used to determine the acute antidepressant-like action of anemoside A3. This action of anemoside A3 was confirmed in chronic mild stress and chronic social defeat stress models. In vitro extracellular field potential recordings were conducted to investigate the impact of anemoside A3 on chronic stress-induced alterations at temporoammonic-CA1 synapses. Western blot, whole-cell patch-clamp recordings, and microinjections of α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor antagonists into the stratum lacunosum-moleculare were performed to unravel the contribution of stratum lacunosum-moleculare α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptors to anemoside A3's antidepressant-like activity. In vivo microdialysis and pharmacological depletion of serotonin were implemented to examine the role of the serotonin system in the antidepressant-like effect of anemoside A3. RESULTS: Anemoside A3 administered intraperitoneally displayed acute antidepressant-like effects in the mouse forced swim test and tail suspension test and anemoside A3 treatment (intraperitoneally) for five days was sufficient to reverse depression-related behaviors of mice subjected to chronic stress. Accordingly, chronic social defeat stress-induced weakening of α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor-mediated neurotransmission in the temporoammonic-CA1 pathway and downregulation of synaptic GluA2-lacking α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor expression in the stratum lacunosum-moleculare could both be normalized by five days of anemoside A3 treatment (intraperitoneally). Moreover, intra-stratum lacunosum-moleculare infusion of GluA2-lacking α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor antagonist abolished anemoside A3's antidepressant-like effect. Lastly, serotonin system was not implicated in anemoside A3's antidepressant-like effect. CONCLUSIONS: Our results suggest that anemoside A3 induces a rapid antidepressant-like response by a stratum lacunosum-moleculare GluA2-lacking α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor-dependent mechanism. In view of this, anemoside A3 represents a promising agent for depression treatment.


Asunto(s)
Antidepresivos/farmacología , Depresión/tratamiento farmacológico , Saponinas/farmacología , Transmisión Sináptica/efectos de los fármacos , Triterpenos/farmacología , Animales , Conducta Animal/efectos de los fármacos , Depresión/fisiopatología , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Estrés Psicológico/tratamiento farmacológico , Natación
7.
Int J Nanomedicine ; 12: 3295-3302, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28458547

RESUMEN

Dendrite-like cobalt selenide nanostructures were synthesized from cobalt and selenium powder precursors by a solvothermal method in anhydrous ethylenediamine. The as-prepared nanocrystalline cobalt selenide was found to possess peroxidase-like activity that could catalyze the reaction of peroxidase substrates in the presence of H2O2. A spectrophotometric method for uric acid (UA) determination was developed based on the nanocrystalline cobalt selenide-catalyzed coupling reaction between N-ethyl-N-(3-sulfopropyl)-3-methylaniline sodium salt and 4-aminoantipyrine (4-AAP) in the presence of H2O2. Under optimum conditions, the absorbance was proportional to the concentration of UA over the range of 2.0-40 µM with a detection limit of 0.5 µM. The applicability of the proposed method has been validated by determination of UA in human serum samples with satisfactory results.


Asunto(s)
Cobalto/química , Nanopartículas del Metal/química , Espectrofotometría/métodos , Ácido Úrico/sangre , Ampirona/química , Análisis Químico de la Sangre/métodos , Catálisis , Humanos , Peróxido de Hidrógeno/química , Límite de Detección , Nanoestructuras/química , Peroxidasa , Peroxidasas/química , Peroxidasas/metabolismo
8.
Front Cell Neurosci ; 11: 391, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29311826

RESUMEN

The spinal cord injury (SCI) is a detrimental neurological disease involving the primary mechanical injury and secondary inflammatory damage. Curtailing the detrimental neuroinflammation would be beneficial for spinal cord function recovery. Microglia reside in the spinal cord and actively participate in the onset, progression and perhaps resolution of post-SCI neuroinflammation. In the current study, we tested the effects of methylene blue on microglia both in vitro and in a rat SCI model. We found that methylene blue inhibited the protein levels of IL-1ß and IL-18 rather than their mRNA levels in activated microglia. Further investigation indicated that methylene blue deceased the activation of NLRP3 inflammasome and NLRC4 inflammasome in microglia in vitro. Moreover, in the rat SCI model, the similar effect of methylene blue on post-SCI microglia was also observed, except that the activation of NLRC4 inflammasome was not seen. The inhibition of microglia NLRP3 inflammasome was associated with down-regulation of intracellular reactive oxygen species (ROS). The administration of methylene blue mitigated the overall post-SCI neuroinflammation, demonstrated by decreased pro-inflammatory cytokine production and leukocyte infiltrates. Consequently, the neuronal apoptosis was partially inhibited and the hind limb locomotor function was ameliorated by methylene blue treatment. Our research highlights the role of methylene blue in inhibiting post-SCI neuroinflammation, and suggests that methylene blue might be used for SCI therapy.

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