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1.
Eur J Radiol ; 169: 111135, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37918090

RESUMO

PURPOSE: To investigate the effect of sub-satisfactory stenting recanalization of severe vascular stenosis of the posterior circulation on cerebral hemodynamic perfusion. MATERIALS AND METHODS: Patients with severe vascular stenosis of the posterior circulation who had undergone three-dimensional cerebral angiography before and after stenting were retrospectively enrolled. Computational fluid dynamic (CFD) analysis of hemodynamic parameters at the stenosis, perforating branch, and normal arterial segments proximal and distal to the stenosis were performed. RESULTS: Sixty-two patients with basilar artery stenosis aged 60.9 ±â€¯9.6 years were enrolled, and stent angioplasty resulted in the reduction of stenosis degree from 85.3 ±â€¯7.2% before to 18.6 ±â€¯6.4% after stenting. After stenting, at the proximal normal artery, the total pressures had significantly (P < 0.05) decreased, whereas all the other parameters (WSS, cell Reynolds number, velocity, vorticity, turbulence intensity, turbulence kinetic energy and dissipation rate) had significantly (P < 0.05) increased. At the stenosis, all hemodynamic parameters had significantly decreased. At the stenosis perforating branch, the WSS, cell Reynolds number, velocity, and vorticity were all significantly decreased, and the total pressure, turbulence intensity, kinetic energy, and dissipation rate were all significantly increased. At the distal normal artery, the total flow pressure (perfusion pressure) and velocity were both significantly (P < 0.05) increased, and the total pressure, WSS, cell Reynolds number, vorticity, turbulence intensity, kinetic energy, and dissipation rate were all significantly (P < 0.05) decreased. The hemodynamic parameters after stenting were closer to those after virtual stenosis repair at all measurements. CONCLUSION: Sub-satisfactory recanalization has significantly restored the stenosis and improved the hemodynamic parameters near the stenosis and at the root of the perforating branch, thus significantly improving the cerebral perfusion, similar to the changes of hemodynamic status and cerebral perfusion after virtual removal of the vascular stenosis. This may indicate the good effect of sub-satisfactory stenting recanalization of the vascular stenosis at the posterior circulation.


Assuntos
Estenose das Carótidas , Hemodinâmica , Humanos , Constrição Patológica/cirurgia , Estudos Retrospectivos , Circulação Cerebrovascular , Perfusão , Stents
2.
Eur J Med Res ; 28(1): 286, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37592323

RESUMO

PURPOSE: To investigate the safety and efficacy of Enterprise stent angioplasty and risk factors for the prognoses in treating symptomatic severe posterior circulation atherosclerotic stenosis (SSPCAS). MATERIALS AND METHODS: Patients with SSPCAS who were treated with the Enterprise stent angioplasty were retrospectively enrolled. The clinical data, peri-procedural complications, postoperative residual stenosis, in-stent restenosis and recurrent stroke at follow-up were analyzed. RESULTS: 262 patients with 275 stenotic lesions treated with the Enterprise stent angioplasty were enrolled. The stenosis degree was reduced from 86.3 ± 6.2% before to 19.3 ± 5.4% after stenting. Complications occurred in 14 (5.3%) patients. Clinical follow-up was performed in 245 (93.51%) patients for 16.5 ± 7.3 months. During 1 year follow-up, 7 patients (2.9%) had recurrent symptoms, including 4 patients with stenting in the intracranial vertebral artery and 3 in the basilar artery. Imaging follow-up was conducted in 223 (85.11%) patients. In-stent restenosis was present in 35 patients (15.7%), with the restenosis rate of 26.4% (n = 23) in the intracranial vertebral artery, which was significantly (P < 0.001) greater than in the basilar artery (8.8%). Six patients (17.1%) with in-stent restenosis were symptomatic. The stenotic length was the only significant (P = 0.026 and 0.024, respectively) independent risk factor for 1 year stroke or death events and in-stent restenosis. CONCLUSION: The Enterprise stent can be safely and efficaciously applied in the treatment of symptomatic severe posterior circulation atherosclerotic stenosis, with a relatively low rate of in-stent restenosis and recurrent stroke within 1 year. The stenotic length was the only significant independent risk factor for 1 year stroke or death events and in-stent restenosis.


Assuntos
Reestenose Coronária , Acidente Vascular Cerebral , Humanos , Constrição Patológica/cirurgia , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Artérias
3.
Psychol Med ; 51(1): 90-101, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-31685046

RESUMO

BACKGROUND: The microbiota-gut-brain axis, especially the microbial tryptophan (Trp) biosynthesis and metabolism pathway (MiTBamp), may play a critical role in the pathogenesis of major depressive disorder (MDD). However, studies on the MiTBamp in MDD are lacking. The aim of the present study was to analyze the gut microbiota composition and the MiTBamp in MDD patients. METHODS: We performed shotgun metagenomic sequencing of stool samples from 26 MDD patients and 29 healthy controls (HCs). In addition to the microbiota community and the MiTBamp analyses, we also built a classification based on the Random Forests (RF) and Boruta algorithm to identify the gut microbiota as biomarkers for MDD. RESULTS: The Bacteroidetes abundance was strongly reduced whereas that of Actinobacteria was significantly increased in the MDD patients compared with the abundance in the HCs. Most noteworthy, the MDD patients had increased levels of Bifidobacterium, which is commonly used as a probiotic. Four Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K01817, K11358, K01626, K01667) abundances in the MiTBamp were significantly lower in the MDD group. Furthermore, we found a negative correlation between the K01626 abundance and the HAMD scores in the MDD group. Finally, RF classification at the genus level can achieve an area under the receiver operating characteristic curve of 0.890. CONCLUSIONS: The present findings enabled a better understanding of the changes in gut microbiota and the related Trp pathway in MDD. Alterations of the gut microbiota may have the potential as biomarkers for distinguishing MDD patients form HCs.


Assuntos
Transtorno Depressivo Maior/fisiopatologia , Microbioma Gastrointestinal , Triptofano/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade
4.
J Affect Disord ; 278: 311-319, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979562

RESUMO

BACKGROUND: The microbiome-gut-brain axis, especially the microbial tryptophan biosynthesis and metabolism pathway (MiTBamp), is closely connected to bipolar disorder with current major depressive episode (BPD). METHODS: We performed shotgun metagenomics sequencing (SMS) of faecal samples from 25 BPD patients and 28 healthy controls (HCs). Except for the microbiota taxa and MiTBamp analyses, we also built a classification model using the Random Forests (RF) and Boruta algorithm to find the microbial biomarkers for BPD. RESULTS: Compared to HCs, the phylum Bacteroidetes abundance was significantly reduced, whereas that of the Actinobacteria and Firmicutes were significantly increased in BPD patients. We also identified 38 species increased and 6 species decreased significantly in the BPD group. In the MiTBamp, we identified that two Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologies (KOs) (K00658 and K00837) were significantly lower in the BPD, and five KOs (K01696, K00382, K00626, K01667, and K03781) were significantly higher in the BPD group. We also identified significant genera and species which were closely related to these KOs. Finally, RF classification based on gut microbiota at the genus level can achieve an area under the receiver operating characteristic curve of 0.997. LIMITATIONS: The features of cross-sectional design, limited sample size, the heterogeneity of bipolar disorders, and a lack of serum/plasma tryptophan concentration measurements. CONCLUSIONS: The present findings enable a better understanding of changes in gastrointestinal microbiome and MiTBamp in BPD. Alterations of microbes may have potential as biomarkers for distinguishing the BPD patients form HCs.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Microbioma Gastrointestinal , Transtorno Bipolar/genética , Estudos Transversais , Transtorno Depressivo Maior/genética , Microbioma Gastrointestinal/genética , Humanos , Metagenômica , Triptofano
5.
Int J Psychiatry Clin Pract ; 23(3): 164-170, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31035798

RESUMO

Introduction: In recent years, evidence has accumulated to suggest that patients with bipolar disorder show altered processing of emotionally relevant information. However, only a few studies have examined manic patients' eye movements when processing facial expressions. Method: A free viewing task and anti-saccade task were used separately to investigate attentional bias and response inhibition while processing emotional stimuli. Data were drawn from matched samples of manic patients (n = 25) and healthy controls (n = 20). Results: The analyses of eye-movement data revealed that there was a significant difference between manic patients and healthy controls in the total duration of fixations but not in the orientation or duration of the first fixation. However, no significant differences between manic patients and healthy controls in response inhibition were detected. Conclusion: These results demonstrate that compared to healthy controls, manic patients show a deficiency in processing speed. The patients showed no attentional vigilance to happy or sad expressions but did showed avoidance of the sad expression and focused more on the happy expression in later emotion processing. There were no impairments of response inhibition detected in manic patients. Key points Abnormal processing of emotional information and having aberrant inner-experiences of emotion is a feature of bipolar disorders. Processing speed is slow in manic patients versus healthy controls. Manic patients focused lesser on sad expression than healthy controls, which suggesting an avoidance of sad expressions. The findings show that psychotherapies like CBT may be applicable to manic patients.


Assuntos
Viés de Atenção/fisiologia , Transtorno Bipolar/fisiopatologia , Movimentos Oculares/fisiologia , Expressão Facial , Inibição Psicológica , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
6.
J Psychiatr Res ; 113: 90-99, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30927646

RESUMO

BACKGROUND: To probe the differences of gut microbiota among major depressive disorder (MDD), bipolar disorder with current major depressive episode (BPD) and health participants. METHODS: Thirty one MDD patients, thirty BPD patients, and thirty healthy controls (HCs) were recruited. All the faecal samples were analyzed by shotgun metagenomics sequencing. Except for routine analyses of alpha diversity, we specially designed a new indicator, the Gm coefficient, to evaluate the inequality of relative abundances of microbiota for each participant. RESULTS: The Gm coefficients are significant decreased in both MDD and BPD groups. The relative abundances of increased phyla Firmicutes and Actinobacteria and decreased Bacteroidetes were significantly in the MDD and BPD groups. At genus level, four of top five enriched genera (Bacteroides, Clostridium, Bifidobacterium, Oscillibacter and Streptococcus) were found increased significantly in the MDD and BPD groups compared with HCs. The genera Escherichia and Klebsiella showed significant changes in abundances only between the BPD and HC groups. At the species level, compared with BPD patients, MDD patients had a higher abundance of Prevotellaceae including Prevotella denticola F0289, Prevotella intermedia 17, Prevotella ruminicola, and Prevotella intermedia. Furthermore, the abundance of Fusobacteriaceae, Escherichia blattae DSM 4481 and Klebsiella oxytoca were significantly increased, whereas the Bifidobacterium longum subsp. infantis ATCC 15697 = JCM 1222 was significantly reduced in BPD group compared with MDD group. CONCLUSIONS: Our study suggested that gut microbiota may be involved in the pathogenesis of both MDD and BPD patients, and the nuances of bacteria may have the potentiality of being the biomarkers of MDD and BPD.


Assuntos
Transtorno Bipolar/microbiologia , Transtorno Depressivo Maior/microbiologia , Microbioma Gastrointestinal/fisiologia , Metagenômica/métodos , Adulto , Fezes/microbiologia , Feminino , Humanos , Masculino , Metagenômica/estatística & dados numéricos
7.
ACS Appl Mater Interfaces ; 8(33): 21770-5, 2016 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-27471861

RESUMO

Ion-conducting materials have received considerable attention for their applications in fuel cells, electrochemical devices, and sensors. Here, flexible indium zinc oxide (InZnO) synaptic transistors with multiple presynaptic inputs gated by proton-conducting phosphorosilicate glass-based electrolyte films are fabricated on ultrathin Si membranes. Transient characteristics of the proton gated InZnO synaptic transistors are investigated, indicating stable proton-gating behaviors. Short-term synaptic plasticities are mimicked on the proposed proton-gated synaptic transistors. Furthermore, synaptic integration regulations are mimicked on the proposed synaptic transistor networks. Spiking logic modulations are realized based on the transition between superlinear and sublinear synaptic integration. The multigates coupled flexible proton-gated oxide synaptic transistors may be interesting for neuroinspired platforms with sophisticated spatiotemporal information processing.

8.
Adv Mater ; 28(28): 5878-85, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27159546

RESUMO

Flexible metal oxide/graphene oxide hybrid multi-gate neuromorphic transistors are fabricated on flexible conducting graphene substrates. Dendritic integrations in both spatial and temporal modes are emulated, and spatiotemporal correlated logics are obtained. A proof-of-principle visual system model for emulating Lobula Giant Motion Detector neuron is also investigated. The results are of great significance for flexible sensors and neuromorphic cognitive systems.

9.
Adv Mater ; 28(18): 3557-63, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26972820

RESUMO

Proton-conducting graphene oxide electrolyte films with very high electric-double-layer capacitance are used as the gate dielectrics for oxide-based neuron transistor fabrication. Paired-pulse facilitation, dendritic integration, and orientation tuning are successfully emulated. Additionally, neuronal gain controls (arithmetic) are also experimentally demonstrated. The results provide a new-concept approach for building brain-inspired cognitive systems.


Assuntos
Neurônios , Encéfalo , Cognição , Grafite , Óxidos , Prótons , Transistores Eletrônicos
10.
ACS Appl Mater Interfaces ; 8(15): 9762-8, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27007748

RESUMO

In the biological nervous system, synaptic plasticity regulation is based on the modulation of ionic fluxes, and such regulation was regarded as the fundamental mechanism underlying memory and learning. Inspired by such biological strategies, indium-gallium-zinc-oxide (IGZO) electric-double-layer (EDL) transistors gated by aqueous solutions were proposed for synaptic behavior emulations. Short-term synaptic plasticity, such as paired-pulse facilitation, high-pass filtering, and orientation tuning, was experimentally emulated in these EDL transistors. Most importantly, we found that such short-term synaptic plasticity can be effectively regulated by alcohol (ethyl alcohol) and salt (potassium chloride) additives. Our results suggest that solution gated oxide-based EDL transistors could act as the platforms for short-term synaptic plasticity emulation.


Assuntos
Eletricidade , Gálio/farmacologia , Índio/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Transistores Eletrônicos , Óxido de Zinco/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Soluções
11.
Sci Rep ; 5: 18082, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-26656113

RESUMO

Inspired by the dendritic integration and spiking operation of a biological neuron, flexible oxide-based neuromorphic transistors with multiple input gates are fabricated on flexible plastic substrates for pH sensor applications. When such device is operated in a quasi-static dual-gate synergic sensing mode, it shows a high pH sensitivity of ~105 mV/pH. Our results also demonstrate that single-spike dynamic mode can remarkably improve pH sensitivity and reduce response/recover time and power consumption. Moreover, we find that an appropriate negative bias applied on the sensing gate electrode can further enhance the pH sensitivity and reduce the power consumption. Our flexible neuromorphic transistors provide a new-concept sensory platform for biochemical detection with high sensitivity, rapid response and ultralow power consumption.


Assuntos
Técnicas Biossensoriais/métodos , Neurofisiologia/métodos , Óxidos/química , Transistores Eletrônicos , Animais , Técnicas Biossensoriais/instrumentação , Dendritos/fisiologia , Capacitância Elétrica , Desenho de Equipamento , Humanos , Concentração de Íons de Hidrogênio , Índio/química , Neurônios/fisiologia , Neurofisiologia/instrumentação , Reprodutibilidade dos Testes , Dióxido de Silício/química , Sinapses/fisiologia , Óxido de Zinco/química
12.
Adv Mater ; 27(37): 5599-604, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26426725

RESUMO

Freestanding synaptic transistors are fabricated on solution-processed chitosan membranes. A short-term memory to long-term memory transition is observed due to proton-related electrochemical doping under repeated pulse stimulus. Moreover, freestanding artificial synaptic devices with multiple presynaptic inputs are investigated, and spiking logic operation and logic modulation are realized.


Assuntos
Quitosana/química , Membranas Artificiais , Modelos Neurológicos , Prótons , Sinapses/química , Transistores Eletrônicos , Potenciais de Ação , Elasticidade , Potenciais Pós-Sinápticos Excitadores , Teste de Materiais , Plasticidade Neuronal , Soluções
13.
ACS Appl Mater Interfaces ; 7(11): 6205-10, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25741771

RESUMO

The control and detection over processing, transport and delivery of chemical species is of great importance in sensors and biological systems. The transient characteristics of the migration of chemical species reflect the basic properties in the processings of chemical species. Here, we observed the field-configurable proton effects in a laterally coupled transistor gated by phosphorosilicate glass (PSG). The bias on the lateral gate would modulate the interplay between protons and electrons at the PSG/indium-zinc-oxide (IZO) channel interface. Due to the modulation of protons flux within the PSG films, the IZO channel current would be modified correspondingly. The characteristic time for the proton gating is estimated to be on the order of 20 ms. Such laterally coupled oxide based transistors with proton gating are promising for low-cost portable biosensors and neuromorphic system applications.


Assuntos
Eletrodos , Índio/química , Transistores Eletrônicos , Óxido de Zinco/química , Transporte de Elétrons , Desenho de Equipamento , Análise de Falha de Equipamento , Prótons , Processamento de Sinais Assistido por Computador/instrumentação
14.
Int J Mol Med ; 31(2): 400-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23229094

RESUMO

The activation of endothelial cells by oxidized low-density lipoprotein (ox-LDL) with subsequent increases in endothelial permeability occurs in the early stage of atherosclerosis. Cathepsin L (CATL) is one of the cysteine proteases and has been implicated in advanced atherosclerotic lesions and plaque instability. This study aimed to explore the role of CATL in ox-LDL-induced early atherosclerotic events and to delineate the underlying mechanism. Results showed that ox-LDL upregulated CATL protein levels and activation in human umbilical vein endothelial cells (ECs) in a concentration-dependent manner and stimulated EC autophagy and apoptosis and increased EC monolayer permeability. Concomitantly, VE-cadherin expression was decreased. When ECs were pretreated with a CATL inhibitor, ox-LDL-induced autophagy was inhibited while apoptosis was further increased. In addition, the VE-cadherin protein level was increased, and the EC monolayer permeability was reduced. Taken together, the present study showed that the upregulated expression and activation of CATL induced by ox-LDL, increased EC autophagy and antagonized EC apoptosis, which partly neutralized the effect of increased EC monolayer permeability mediated by the downregulation of VE-cadherin. Thus, the proatherogenic effect of CATL was partly neutralized by inducing autophagy and inhibiting apoptosis in early stages of atherosclerosis.


Assuntos
Catepsina L/metabolismo , Células Endoteliais/enzimologia , Lipoproteínas LDL/metabolismo , Antígenos CD/metabolismo , Apoptose/efeitos dos fármacos , Aterosclerose/tratamento farmacológico , Aterosclerose/enzimologia , Aterosclerose/genética , Aterosclerose/patologia , Autofagia/efeitos dos fármacos , Caderinas/metabolismo , Catepsina L/antagonistas & inibidores , Catepsina L/genética , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Ativação Enzimática , Células Endoteliais da Veia Umbilical Humana , Humanos , Permeabilidade/efeitos dos fármacos , Inibidores de Proteases/farmacologia , RNA Mensageiro/genética , Regulação para Cima
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