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1.
Small ; 20(26): e2306483, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38229561

RESUMO

As a highly promising nanomaterial, exploring the impact of the liver, a vital organ, stands out as a crucial focus in the examination of its biological effects. Kupffer cells (KCs) are one of the first immune cells to contact with exotic-substances in liver. Therefore, this study investigates the immunomodulatory effects and mechanisms of polyethylene glycol-modified graphene oxide (GO-PEG) on KCs. Initial RNA-seq and KEGG pathway analyses reveal the inhibition of the TOLL-like receptor, TNF-α and NOD-like receptor pathways in continually stimulated KCs exposed to GO-PEG. Subsequent biological experiments validate that a 48-hour exposure to GO-PEG alleviates LPS-induced KCs immune activation, characterized by a shift in polarization from M1 to M2. The underlying mechanism involves the absorption of double-stranded RNA/single-stranded RNA, inhibiting the activation of TLR3 and TLR7 in KCs. Employing a Kupffer/AML12 cell co-culture model and animal studies, it is observed that GO-PEG indirectly inhibit oxidative stress, mitochondrial dysfunction, and apoptosis in AML12 cells, partially mitigating systemic inflammation and preserving liver tissue/function. This effect is attributed to the paracrine interaction between KCs and hepatocytes. These findings suggest a meaningful and effective strategy for treating liver inflammation, particularly when combined with anti-inflammatory drugs.


Assuntos
Grafite , Células de Kupffer , Polietilenoglicóis , Células de Kupffer/metabolismo , Células de Kupffer/efeitos dos fármacos , Animais , Grafite/química , Grafite/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Camundongos , Fígado/metabolismo , Fígado/patologia , Fígado/efeitos dos fármacos , Inflamação/patologia , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Masculino , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Progressão da Doença , Polaridade Celular/efeitos dos fármacos , Linhagem Celular
2.
J Appl Toxicol ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837250

RESUMO

In recent years, semiconductor nanomaterials, as one of the most promising and applied classes of engineered nanomaterials, have been widely used in industries such as photovoltaics, electronic devices, and biomedicine. However, occupational exposure is unavoidable during the production, use, and disposal stages of products containing these materials, thus posing potential health risks to workers. The intricacies of the work environment present challenges in obtaining comprehensive data on such exposure. Consequently, there remains a significant gap in understanding the exposure risks and toxic effects associated with semiconductor nanomaterials. This paper provides an overview of the current classification and applications of typical semiconductor nanomaterials. It also delves into the existing state of occupational exposure, methodologies for exposure assessment, and prevailing occupational exposure limits. Furthermore, relevant epidemiological studies are examined. Subsequently, the review scrutinizes the toxicity of semiconductor nanomaterials concerning target organ toxicity, toxicity mechanisms, and influencing factors. The aim of this review is to lay the groundwork for enhancing the assessment of occupational exposure to semiconductor nanomaterials, optimizing occupational exposure limits, and promoting environmentally sustainable development practices in this domain.

3.
Neurosurg Rev ; 47(1): 633, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39292301

RESUMO

Chronic subdural hematoma (CSDH) is a common condition in neurosurgery. With an aging population, there is increasing attention on the prognosis of patients following surgical intervention. We developed a postoperative short-term prognostic prediction model using preoperative clinical indicators, aiming to assist in perioperative medical decision-making and management. The dataset was randomly divided into training and validation cohorts. An mRS score greater than 2 one month after discharge was considered indicative of a poor prognosis. In the training cohort, the least absolute shrinkage and selection operator (LASSO) regression analysis was used for multivariate analysis to identify independent risk factors and construct a prediction nomogram for poor prognosis one month after discharge. The performance of the nomogram was assessed using the Receiver Operating Characteristic (ROC) curve and calibration curve. A Decision Curve Analysis (DCA) was also conducted to determine the net benefit threshold of the prediction model. Among the 505 participants, 18.8% (95/505) had a poor prognosis one month after discharge. The baseline characteristics did not significantly differ between the training cohort and the validation cohort. LASSO regression analysis in the training cohort reduced the predictors to four potential factors. Further multivariate logistic analyses in the training cohort identified four independent predictors: age, admission Glasgow Coma Scale (GCS) score, hemiparesis, and hemoglobin count. These predictors were incorporated into the nomogram prediction model. Internal validation using ROC analysis, calibration curves, and other methods demonstrated a strong correlation between the observed and predicted likelihood of poor prognosis one month after discharge. The visualized nomogram prediction model we developed for short-term postoperative prognosis of chronic subdural hematoma after burr hole drainage aids in predicting short-term outcomes and guiding clinical treatment decisions. Further external validation is needed in the future to confirm its effectiveness.


Assuntos
Drenagem , Hematoma Subdural Crônico , Humanos , Hematoma Subdural Crônico/cirurgia , Masculino , Feminino , Idoso , Prognóstico , Pessoa de Meia-Idade , Drenagem/métodos , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Nomogramas , Trepanação , Adulto , Estudos de Coortes , Fatores de Risco , Escala de Coma de Glasgow
4.
Altern Ther Health Med ; 30(1): 366-373, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37793334

RESUMO

Objective: The differential gene analysis of ferroptosis inreating allergic rhinitis with Bu-Zhong-Yi-Qi-Decoction based on GEO using network pharmacology and molecular docking . Method: This study used databases such as TCMSP to search for traditional Chinese herbal medicine's active ingredients and targets in Bu-Zhong-Yi-Qi-Decoction in treating allergic rhinitis. GeneCards, OMIM, TTD, and PharmaGkb were used to obtain disease targets for allergic rhinitis, and R language was used to screen Bu-Zhong-Yi-Qi-Decoction as the main target for treating allergic rhinitis. Retrieve the gene dataset of allergic rhinitis using the GEO database, analyze ferroptosis-related genes, and select the intersection of effective targets of Bu-Zhong-Yi-Qi-Decoction for treating allergic rhinitis and ferroptosis-related genes of allergic rhinitis, draw protein interaction networks using the STRING database, use Cytoscape software to construct the target regulatory network of Bu-Zhong-Yi-Qi-Decoction for treating allergic rhinitis and ferroptosis related genes, and then use the CytoNCA plugin to screen key targets. Using R language, Gene ontology, and the biological pathway enrichment analysis were performed on the predicted targets related to the treatment of allergic rhinitis and ferroptosis with Bu-Zhong-Yi-Qi-Decoction. Selecting key targets and active ingredients for molecular docking to explore the potential mechanism of Bu-Zhong-Yi-Qi-Decoction in treating ferroptosis in allergic rhinitis. Result: After searching the TCMSP database, a total of 182 active ingredients were obtained from 8 traditional Chinese medicines of Bu-Zhong-Yi-Qi-Decoction, such as naringenin, kaempferol, Isorhamnetin, corresponding to 3023 targets and 2025 targets related to allergic rhinitis. There are 30 remarkably enriched Go analyses for biological function of potential target genes of Bu-Zhong-Yi-Qi-Decoction in allergic rhinitis, such as regulation of apoptotic signaling pathway, cellular response to peptide, wound healing, etc. Among them, there are 7 key genes related to the treatment of allergic rhinitis and ferroptosis with Bu-Zhong-Yi-Qi-Decoction, namely TP53, MAPK1, MAPK14, HIF1A, AR, CAV1, GSK3B. Conclusion: The treatment of allergic rhinitis with Bu-Zhong-Yi-Qi-Decoction is a process involving multiple divisions, targets, and pathways. These results indicated that oral Bu-Zhong-Yi-Qi-Decoction may effectively treat allergic rhinitis in clinical practice.


Assuntos
Medicamentos de Ervas Chinesas , Ferroptose , Humanos , Simulação de Acoplamento Molecular , Farmacologia em Rede , Apoptose , Idioma , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
5.
Mikrochim Acta ; 191(8): 481, 2024 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-39046557

RESUMO

It is crucial to accurately and rapidly monitor the levodopa (LD) concentration for accurate classification and treatment of dyskinesia in Parkinson's disease. In this paper, 3D graphene foam (GF) with a highly conductive network is obtained by chemical vapor deposition. 3D GF serves as the substrate for hydrothermal in situ growth of tapered cross-linked ZnO nanowire bundle arrays (ZnO NWBAs), enabling the development of a highly sensitive detection platform for LD. The formation mechanism of a tapered cross-linked ZnO nanowire bundle arrays on 3D GF is put forward. The integration of 3D GF and ZnO NWBAs can accelerate the electron transfer rate and increase the contact area with biomolecules, resulting in high electrochemical properties. The electrode composed of ZnO NWBAs on 3D GF exhibits significant sensitivity (1.66 µA·µM-1·cm-2) for LD detection in the concentration range 0-60 µM. The electrode is able to rapidly and specifically determine LD in mixed AA or UA solution. The selectivity mechanism of the electrode is also explained by the bandgap model. Furthermore, the successful detection of LD in serum demonstrates the practicality of the electrode and its great potential for clinical application.


Assuntos
Técnicas Eletroquímicas , Grafite , Levodopa , Limite de Detecção , Nanofios , Óxido de Zinco , Grafite/química , Óxido de Zinco/química , Nanofios/química , Levodopa/sangue , Levodopa/análise , Levodopa/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Eletrodos , Humanos
6.
J Sci Food Agric ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39180184

RESUMO

BACKGROUND: Fried dough sticks, widely enjoyed in southeast Asia, are made by frying a mixture of wheat flour and water at high-temperature. With the move towards industrial production, there is an increasing demand for healthier versions. Understanding the key properties of fried dough sticks and how the ingredients interact is crucial for meeting these health-focused consumer preferences. RESULTS: In this study, the connections between the dough's rheological and thermal properties, alongside the interactions between gluten proteins and the oil content in fried dough sticks, were examined and analyzed at varying gliadin to glutenin mass ratios (Gli/Glu). The results indicated that a general decrease in the viscoelastic properties of the dough was associated with an increase in the Gli/Glu ratio. Furthermore, a heightened concentration of gliadin was observed to augment the mass loss of gluten proteins, thereby engendering a spatially sparse network structure. Additionally, this excessive presence of gliadin precipitated the thermal instability within the dough, necessitating an augmented chemical force to preserve the stability of the gluten network structure. CONCLUSION: At the Gli/Glu ratio of 5:5, the gluten protein exhibited enhanced thermal stability and minimal mass loss. At this specific ratio, the gluten network was characterized by a comparatively high prevalence of extended gluten films and short-chain structures, which resulted in the production of fried dough sticks possessing minimal structural oil content. The study provided a theoretical basis for identifying the Gli/Glu ratio as an effective approach to modulate the oil content in fried dough sticks. © 2024 Society of Chemical Industry.

7.
Anticancer Drugs ; 34(10): 1112-1121, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36847079

RESUMO

The natural phenolic compound ellagic acid exerts anti-cancer effects, including activity against colorectal cancer (CRC). Previously, we reported that ellagic acid can inhibit the proliferation of CRC, and can induce cell cycle arrest and apoptosis. This study investigated ellagic acid-mediated anticancer effects using the human colon cancer HCT-116 cell line. After 72 h of ellagic acid treatment, a total of 206 long noncoding RNAs (lncRNAs) with differential expression greater than 1.5-fold were identified (115 down-regulated and 91 up-regulated). Furthermore, the co-expression network analysis of differentially expressed lncRNA and mRNA showed that differential expressed lncRNA might be the target of ellagic acid activity in inhibiting CRC.

8.
Environ Res ; 212(Pt C): 113440, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35526583

RESUMO

This study analyzed an ozone pollution episode that occurred in the summer of 2020 in Zhengzhou, the provincial capital of Henan, China, and quantified the contribution of local and surrounding area anthropogenic emissions to this episode based on the Weather Research and Forecasting with Chemistry (WRF/Chem) model. Simulation results showed that the WRF/Chem model is well suited to simulate the ozone concentrations in this area. In addition, four simulation scenarios (removing the emissions from the northern Zhengzhou, southwestern Zhengzhou, Zhengzhou local and southeastern Zhengzhou) were conducted to explore the specific contributions of local emissions and emissions from surrounding areas within Henan to this ozone pollution episode. We found that contributions from the northern, local, southwestern, and southeastern regions were 6.1%, 5.9%, 1.7%, and 1.5%, respectively. The northern and local emissions of Zhengzhou (only emissions from Zhengzhou) were prominent contributors within the simulation areas. In other words, during this episode, most of the ozone pollution in Zhengzhou appeared to be transported in from regions outside Henan Province.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluição do Ar/estatística & dados numéricos , China , Monitoramento Ambiental/métodos , Ozônio/análise , Tempo (Meteorologia)
9.
Drug Dev Res ; 83(5): 1152-1166, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35472101

RESUMO

Secoisolariciresinol diglucoside (SDG) is the main component of lignans with various biological activities, including anticancer activity. However, whether SDG has obvious anticancer effects on colorectal cancer (CRC) is unclear. Pyroptosis, a form of programmed cell death, has received increasing attention in cancer-related research. In this study, we aimed to test the anticancer properties and relatecd functional mechanisms of SDG. we found that SDG not only inhibited the cell viability of HCT116 cells, but also induced HCT116 cells to swell with apparent large bubbles, which are typical signs of pyroptosis. Furthermore, SDG induced cell pyroptosis by enhancing cleavage of the N-terminal fragment of gasdermin D (GSDMD) in CRC cells, accompanied by increased caspase-1 cleavage. Consistent with this, SDG-induced GSDMD-N-terminal fragment cleavage and pyroptosis were reduced by siRNA-mediated silencing of caspase-1 or treatment with the specific caspase-1 inhibitor VX-765 treatment, suggesting that active caspase-1 further induces pyroptosis. A mechanistic study showed that SDG induced reactive oxygen species (ROS) accumulation and inhibits phosphatidylinositol 3-kinase (PI3K) phosphorylation and increases pyroptosis, while increasing GSDMD and caspase-1 cleavage and enhancing expression of BCL2-associated X (BAX), which could be rescued by the ROS scavenger (NAC), suggesting that SDG-induced GSDME-dependent pyroptosis is related to the ROS/PI3K/AKT/BAX-mitochondrial apoptotic pathway. In vivo results showed that SDG significantly inhibited tumor growth and induced pyroptosis in the HCT116-CRC nude mouse model. In conclusion, our findings suggest that the anticancer activity of SDG in CRC is associated with the induction of GSDMD-dependent pyroptosis by SDG through the generation of ROS/P13K/AKT/BAK-mitochondrail apoptosis pathway, providing insights into SDG in its potential new application in cancer treatment.


Assuntos
Neoplasias Colorretais , Proteínas de Ligação a Fosfato , Proteínas Citotóxicas Formadoras de Poros , Piroptose , Animais , Butileno Glicóis , Caspase 1/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Glucosídeos , Células HCT116 , Humanos , Camundongos , Proteínas de Ligação a Fosfato/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Proteínas Proto-Oncogênicas c-akt , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2
10.
J Environ Manage ; 324: 116379, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36202037

RESUMO

Ground-level ozone (O3) has negative effects on agricultural crops. Maize is an important grain crop in China. The North China Plain (NCP) serves as the major crops' production area of China and experiences severe ozone pollution. Using the ground-level ozone simulated by an atmospheric chemistry transport model (WRF-Chem), we quantified the yield reduction and economic losses of maize during 2015-2018 over NCP based on exposure-response AOT40 (accumulation of hourly O3 concentration exceed 40 ppb) and flux-response POD6 (phytotoxic dose of ozone over 6 nmol m-2 s-1). Results showed that the ozone concentration, AOT40, and POD6 clearly increased from 2015 to 2018 in growing season of maize over NCP. The four-year annual mean ozone concentration, AOT40, and POD6 were 0.055 ppm, 18.02 ppm h, and 5.02 mmol m-2, respectively. At county level, the relative loss of maize yield (MRYL) based on AOT40 and POD6 had clearly spatio-temporal differences in NCP. The average MRYLs of AOT40 and of POD6 from 2015 to 2018 were 10.4% and 21.4%, respectively, and these reductions were associated with 2399 million and 5637 million US dollars, respectively. This study suggests that surface ozone increased the yield losses of maize, and indicates that further reductions in ozone concentrations can enhance the food security in China.


Assuntos
Poluentes Atmosféricos , Ozônio , Ozônio/análise , Zea mays , Poluentes Atmosféricos/análise , Produtos Agrícolas/fisiologia , China
11.
Sensors (Basel) ; 19(14)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340511

RESUMO

In the case of space-based space surveillance (SBSS), images of the target space objects captured by space-based imaging sensors usually suffer from low spatial resolution due to the extremely long distance between the target and the imaging sensor. Image super-resolution is an effective data processing operation to get informative high resolution images. In this paper, we comparably study four recent popular models for single image super-resolution based on convolutional neural networks (CNNs) with the purpose of space applications. We specially fine-tune the super-resolution models designed for natural images using simulated images of space objects, and test the performance of different CNN-based models in different conditions that are mainly considered for SBSS. Experimental results show the advantages and drawbacks of these models, which could be helpful for the choice of proper CNN-based super-resolution method to deal with image data of space objects.

12.
J Neurosci ; 37(12): 3364-3377, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28258168

RESUMO

Loss of dopaminergic (DA) neurons leads to Parkinson's disease; however, the mechanism(s) for the vulnerability of DA neurons is(are) not fully understood. We demonstrate that TRPC1 regulates the L-type Ca2+ channel that contributes to the rhythmic activity of adult DA neurons in the substantia nigra region. Store depletion that activates TRPC1, via STIM1, inhibits the frequency and amplitude of the rhythmic activity in DA neurons of wild-type, but not in TRPC1-/-, mice. Similarly, TRPC1-/- substantia nigra neurons showed increased L-type Ca2+ currents, decreased stimulation-dependent STIM1-Cav1.3 interaction, and decreased DA neurons. L-type Ca2+ currents and the open channel probability of Cav1.3 channels were also reduced upon TRPC1 activation, whereas increased Cav1.3 currents were observed upon STIM1 or TRPC1 silencing. Increased interaction between Cav1.3-TRPC1-STIM1 was observed upon store depletion and the loss of either TRPC1 or STIM1 led to DA cell death, which was prevented by inhibiting L-type Ca2+ channels. Neurotoxins that mimic Parkinson's disease increased Cav1.3 function, decreased TRPC1 expression, inhibited Tg-mediated STIM1-Cav1.3 interaction, and induced caspase activation. Importantly, restoration of TRPC1 expression not only inhibited Cav1.3 function but increased cell survival. Together, we provide evidence that TRPC1 suppresses Cav1.3 activity by providing an STIM1-based scaffold, which is essential for DA neuron survival.SIGNIFICANCE STATEMENT Ca2+ entry serves critical cellular functions in virtually every cell type, and appropriate regulation of Ca2+ in neurons is essential for proper function. In Parkinson's disease, DA neurons are specifically degenerated, but the mechanism is not known. Unlike other neurons, DA neurons depend on Cav1.3 channels for their rhythmic activity. Our studies show that, in normal conditions, the pacemaking activity in DA neurons is inhibited by the TRPC1-STIM1 complex. Neurotoxins that mimic Parkinson's disease target TRPC1 expression, which leads to an abnormal increase in Cav1.3 activity, thereby causing degeneration of DA neurons. These findings link TRPC1 to Cav1.3 regulation and provide important indications about how disrupting Ca2+ balance could have a direct implication in the treatment of Parkinson's patients.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Sinalização do Cálcio/fisiologia , Sobrevivência Celular/fisiologia , Neurônios Dopaminérgicos/patologia , Molécula 1 de Interação Estromal/metabolismo , Canais de Cátion TRPC/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Neurônios Dopaminérgicos/citologia , Ativação do Canal Iônico/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
13.
Sensors (Basel) ; 18(4)2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29561828

RESUMO

Automatic component detection of spacecraft can assist in on-orbit operation and space situational awareness. Spacecraft are generally composed of solar panels and cuboidal or cylindrical modules. These components can be simply represented by geometric primitives like plane, cuboid and cylinder. Based on this prior, we propose a robust automatic detection scheme to automatically detect such basic components of spacecraft in three-dimensional (3D) point clouds. In the proposed scheme, cylinders are first detected in the iteration of the energy-based geometric model fitting and cylinder parameter estimation. Then, planes are detected by Hough transform and further described as bounded patches with their minimum bounding rectangles. Finally, the cuboids are detected with pair-wise geometry relations from the detected patches. After successive detection of cylinders, planar patches and cuboids, a mid-level geometry representation of the spacecraft can be delivered. We tested the proposed component detection scheme on spacecraft 3D point clouds synthesized by computer-aided design (CAD) models and those recovered by image-based reconstruction, respectively. Experimental results illustrate that the proposed scheme can detect the basic geometric components effectively and has fine robustness against noise and point distribution density.

14.
Cereb Cortex ; 26(3): 977-90, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25405940

RESUMO

Neurotensin (NT) is a 13-amino acid peptide and serves as a neuromodulator in the brain. Whereas NT has been implicated in learning and memory, the underlying cellular and molecular mechanisms are ill-defined. Because the dentate gyrus receives profound innervation of fibers containing NT and expresses high density of NT receptors, we examined the effects of NT on the excitability of dentate gyrus granule cells (GCs). Our results showed that NT concentration dependently increased action potential (AP) firing frequency of the GCs by the activation of NTS1 receptors resulting in the depolarization of the GCs. NT-induced enhancement of AP firing frequency was not caused indirectly by releasing glutamate, GABA, acetylcholine, or dopamine, but due to the inhibition of TASK-3 K(+) channels. NT-mediated excitation of the GCs was G protein dependent, but independent of phospholipase C, intracellular Ca(2+) release, and protein kinase C. Immunoprecipitation experiment demonstrates that the activation of NTS1 receptors induced the association of Gαq/11 and TASK-3 channels suggesting a direct coupling of Gαq/11 to TASK-3 channels. Endogenously released NT facilitated the excitability of the GCs contributing to the induction of long-term potentiation at the perforant path-GC synapses. Our results provide a cellular mechanism that helps to explain the roles of NT in learning and memory.


Assuntos
Giro Denteado/fisiologia , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Neurônios/fisiologia , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Canais de Potássio/metabolismo , Receptores de Neurotensina/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Giro Denteado/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Células HEK293 , Humanos , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurotensina/metabolismo , Canais de Potássio/genética , Ratos Sprague-Dawley , Receptores de Neurotensina/genética , Técnicas de Cultura de Tecidos
15.
Sensors (Basel) ; 17(7)2017 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-28737675

RESUMO

In this paper, a novel 3D reconstruction framework is proposed to recover the 3D structural model of a space object from its multi-view images captured by a visible sensor. Given an image sequence, this framework first estimates the relative camera poses and recovers the depths of the surface points by the structure from motion (SFM) method, then the patch-based multi-view stereo (PMVS) algorithm is utilized to generate a dense 3D point cloud. To resolve the wrong matches arising from the symmetric structure and repeated textures of space objects, a new strategy is introduced, in which images are added to SFM in imaging order. Meanwhile, a refining process exploiting the structural prior knowledge that most sub-components of artificial space objects are composed of basic geometric shapes is proposed and applied to the recovered point cloud. The proposed reconstruction framework is tested on both simulated image datasets and real image datasets. Experimental results illustrate that the recovered point cloud models of space objects are accurate and have a complete coverage of the surface. Moreover, outliers and points with severe noise are effectively filtered out by the refinement, resulting in an distinct improvement of the structure and visualization of the recovered points.

16.
Hippocampus ; 25(11): 1299-313, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25740117

RESUMO

Whereas the ionotropic glutamate receptors are the major mediator in glutamatergic transmission, the metabotropic glutamate receptors (mGluRs) usually play a modulatory role. Whereas the entorhinal cortex (EC) is an essential structure involved in the generation and propagation of epilepsy, the roles and mechanisms of mGluRs in epilepsy in the EC have not been determined. Here, we studied the effects of activation of group II metabotropic glutamate receptors (mGluRs II) on epileptiform activity induced by picrotoxin or deprivation of extracellular Mg2+ and neuronal excitability in the medial EC. We found that activation of mGluRs II by application of the selective agonist, LY354740, exerted robust inhibition on epileptiform activity. LY354740 hyperpolarized entorhinal neurons via activation of a K+ conductance and inhibition of a Na+ -permeable channel. LY354740-induced hyperpolarization was G protein-dependent, but independent of adenylyl cyclase and protein kinase A. However, the function of Gßγ was involved in mGluRs II-mediated depression of both neuronal excitability and epileptiform activity. Our results provide a novel cellular mechanism to explain the antiepileptic effects of mGluRs II in the treatment of epilepsy.


Assuntos
Córtex Entorrinal/metabolismo , Epilepsia/metabolismo , Magnésio/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Potenciais Sinápticos/fisiologia , Animais , Compostos Bicíclicos com Pontes/farmacologia , Modelos Animais de Doenças , Córtex Entorrinal/efeitos dos fármacos , Epilepsia/tratamento farmacológico , Agonistas de Aminoácidos Excitatórios/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Glutamato Metabotrópico/agonistas , Potenciais Sinápticos/efeitos dos fármacos
17.
Hippocampus ; 24(1): 21-31, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23966303

RESUMO

Bombesin and the bombesin-like peptides including neuromedin B (NMB) and gastrin-releasing peptide (GRP) are important neuromodulators in the brain. We studied their effects on GABAergic transmission and epileptiform activity in the entorhinal cortex (EC). Bath application of bombesin concentration-dependently increased both the frequency and amplitude of sIPSCs recorded from the principal neurons in the EC. Application of NMB and GRP exerted the same effects as bombesin. Bombesin had no effects on mIPSCs recorded in the presence of TTX but slightly depressed the evoked IPSCs. Omission of extracellular Ca(2+) or inclusion of voltage-gated Ca(2+) channel blockers, Cd(2+) and Ni(2+), blocked bombesin-induced increases in sIPSCs suggesting that bombesin increases GABA release via facilitating extracellular Ca(2+) influx. Bombesin induced membrane depolarization and slightly increased the input resistance of GABAergic interneurons recorded from layer III of the EC. The action potential firing frequency of the interneurons was also increased by bombesin. Bombesin-mediated depolarization of interneurons was unlikely to be mediated by the opening of a cationic conductance but due to the inhibition of inward rectifier K(+) channels. Bath application of bombesin, NMB and GRP depressed the frequency of the epileptiform activity elicited by deprivation of Mg(2+) from the extracellular solution suggesting that bombesin and the bombesin-like peptides have antiepileptic effects in the brain.


Assuntos
Anticonvulsivantes/farmacologia , Bombesina/farmacologia , Córtex Entorrinal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Bombesina/metabolismo , Córtex Entorrinal/fisiologia , Epilepsia/metabolismo , Epilepsia/fisiopatologia , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Potenciais Pós-Sinápticos Inibidores/fisiologia , Neurônios/fisiologia , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Convulsões/metabolismo , Convulsões/fisiopatologia , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/metabolismo
18.
Drug Des Devel Ther ; 18: 2837-2845, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006192

RESUMO

Background: To investigate the effects of nalbuphine on emergency agitation (EA), which affects up to 80% of the children following otolaryngology procedures, in children undergoing cochlear implantation. Methods: A prospective double-blinded randomized controlled clinical trial was conducted between November 2020 and October 2022. Eligible children, aged 6 months to 3 years old, were randomly assigned to either 0.1 mg/kg, 0.15 mg/kg, 0.2 mg/kg nalbuphine or 0.9% saline groups. EA was defined by the Pediatric Anesthesia Emergence Delirium (PAED) score ≥10. Extubation time, post-anesthesia care unit (PACU) length of stay, severe EA (PAED ≥ 15), peak PAED score, the Faces, Legs, Activity, Cry, and Consolability (FLACC) scale, Ramsay sedation score, and adverse events were also recorded. Results: A total of 104 children were enrolled, with 26 children in each group. Nalbuphine significantly reduced the EA occurrence from 73.1% in the saline group to 38.5%, 30.8%, and 26.9% in the 0.1 mg/kg, 0.15 mg/kg, and 0.2 mg/kg nalbuphine groups, respectively (P < 0.001), without affecting the extubation time and PACU length of stay. More children (34.6%) in the 0.9% saline group experienced severe EA. Higher dose nalbuphine (0.15 mg/kg, 0.2 mg/kg) showed lower peak PAED score, better analgesia and sedation effect compared with 0.1 mg/kg nalbuphine and saline groups. However, 0.2mg/kg nalbuphine caused undesired over-sedation in two (7.7%) children. No other adverse events were reported. Conclusion: Young children undergoing cochlear implantation surgery were at a high risk of EA and postoperative pain, while 0.2 mg/kg nalbuphine might be an ideal candidate for EA and pain prevention when used under close monitoring. Trial Registration: ChiCTR2000040407.


Assuntos
Analgésicos Opioides , Implante Coclear , Delírio do Despertar , Nalbufina , Humanos , Nalbufina/administração & dosagem , Nalbufina/uso terapêutico , Pré-Escolar , Masculino , Método Duplo-Cego , Feminino , Estudos Prospectivos , Lactente , Delírio do Despertar/prevenção & controle , Delírio do Despertar/tratamento farmacológico , Implante Coclear/efeitos adversos , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Relação Dose-Resposta a Droga , Agitação Psicomotora/tratamento farmacológico , Agitação Psicomotora/prevenção & controle
19.
Curr Drug Metab ; 25(1): 81-90, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38468514

RESUMO

BACKGROUND: Propofol is an intravenous agent for clinical anesthesia. As the influence of the hypobaric-hypoxic environment (Qinghai-Tibetan region, altitude: 2800-4300 m, PaO2: 15.1-12.4 kPa) on the metabolism of Propofol is complex, the research results on the metabolic characteristics of Propofol in high-altitude areas remain unclear. This study aimed to investigate the pharmacokinetic characteristics of Propofol in a high-altitude hypoxic environment using animal experiments. METHODS: Rats were randomly divided into three groups: high-altitude, medium-altitude, and plain groups. The time of disappearance and recovery of the rat righting reflex was recorded as the time of anesthesia induction and awakening, respectively. The plasma concentration of Propofol was determined by gas chromatography-mass spectrometry. A pharmacokinetic analysis software was used to analyze the blood-drug concentrations and obtain the pharmacokinetic parameters. RESULTS: We observed that when Propofol anesthetizes rats, the anesthesia induction time was shortened, and the recovery time was prolonged with increased altitude. Compared with the plain group, the clearance of Propofol decreased, whereas the half-life, area under the concentration-time curve, peak plasma concentration, and average residence time extension increased. CONCLUSION: The pharmacokinetic characteristics of Propofol are significantly altered in high-altitude hypoxic environments.


Assuntos
Altitude , Anestésicos Intravenosos , Propofol , Ratos Sprague-Dawley , Animais , Propofol/farmacocinética , Propofol/sangue , Masculino , Anestésicos Intravenosos/farmacocinética , Anestésicos Intravenosos/sangue , Ratos , Hipóxia
20.
J Colloid Interface Sci ; 675: 1130-1148, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39180811

RESUMO

This study investigates the corrosion inhibition effect and adsorption process of two imidazoline corrosion inhibitors, HEIE and TDEI, on pre-eroded X65 steel surfaces. Analysis of weight loss and electrochemical measurements suggests that the irregular structure of pre-eroded surfaces may impede the uniform adsorption of corrosion inhibitors, resulting in reduced effectiveness pre-erosion. Particularly, at a 30° angle of pre-erosion, corrosion inhibition efficacy is observed to be at its lowest. The corrosion inhibition rates of HEIE and TDEI on X65 steel surfaces are found to be 11.9 % lower under pre-eroded conditions at a 30° angle compared to non-eroded surfaces at the same angle. Molecular dynamics (MD) simulations support these findings, indicating that TDEI exhibits lower energy bandgap values and more negative adsorption energies (Eads) compared to HEIE, aligning with experimental results. Moreover, TDEI demonstrates a smaller diffusion coefficient for corrosive agents than HEIE, suggesting stronger adsorption efficiency and a more pronounced protective effect. Study of the corrosion inhibition effect on pre-eroded surfaces provides new ideas and methods for improving protective measures.

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