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1.
Artigo em Inglês | MEDLINE | ID: mdl-38976648

RESUMO

OBJECTIVES: To investigate the risk factors and prognosis of spinal cord injury (SCI) after surgical procedure in type A aortic dissection (AAD). METHODS: Between January 2013 and December 2021, a total of 1647 patients with AAD underwent surgical procedure. Postoperative SCI occurred in 58 patients, including 24 patients with paraplegia and 34 patients with paraparesis. Factors associated with SCI was identified through comparison between patients with and without SCI. RESULTS: The mean age was 48.8 ± 10.8 years for patients with SCI and 50.1 ± 12.1 years for those without SCI (P = 0.43), with a comparable gender distribution. Median numbers of intercostal and lumbar arteries with involvement were significantly higher in the SCI group (both P < 0.001). The highest (P = 0.033) and lowest (P = 0.001) level of intraoperative mean arterial pressure (MAP) were significantly lower in the SCI group. Multivariable analysis revealed number of segmental arteries involved (odds ratio [OR]=1.14, 95% CI 1.08-1.20, P = 0.000) and duration of hypothermic circulatory arrest (HCA) (OR = 1.04, 95% CI 1.01-1.08, P = 0.042) were positively associated with the occurrence of SCI. Conversely, the lowest level of MAP was negatively associated with SCI (OR = 0.98, 95% CI 0.96-0.99, P = 0.031). During the long-term follow-up, 14 patients with paraplegia needed the wheel chair, while only one patient with paraparesis needed one (P < 0.001). CONCLUSIONS: The risk of postoperative SCI increases when AAD patients experience segmental arteries involved, longer HCA duration, and decreased intraoperative MAP during operation.

3.
Sci Rep ; 14(1): 12134, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802431

RESUMO

Online rumors are widespread and difficult to identify, which bring serious harm to society and individuals. To effectively detect and govern online rumors, it is necessary to conduct in-depth semantic analysis and understand the content features of rumors. This paper proposes a TFI domain ontology construction method, which aims to achieve semantic parsing and reasoning of the rumor text content. This paper starts from the term layer, the frame layer, and the instance layer, and based on the reuse of the top-level ontology, the extraction of core literature content features, and the discovery of new concepts in the real corpus, obtains the core classes (five parent classes and 88 subclasses) of the rumor domain ontology and defines their concept hierarchy. Object properties and data properties are designed to describe relationships between entities or their features, and the instance layer is created according to the real rumor datasets. OWL language is used to encode the ontology, Protégé is used to visualize it, and SWRL rules and pellet reasoner are used to mine and verify implicit knowledge of the ontology, and judge the category of rumor text. This paper constructs a rumor domain ontology with high consistency and reliability.

4.
Analyst ; 147(20): 4500-4509, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36069275

RESUMO

Paper-based microfluidic solution sampling is a viable option for potentiometric sensors to be used for the determination of analytes in samples with high solid-to-liquid ratios. Unfortunately, heavy metal sensitive electrodes cannot be easily integrated with paper-based solution sampling as heavy metals have strong physicochemical adsorption affinity towards paper substrates. In this work, paper substrates were modified with an ion-selective membrane (ISM) cocktail (used for the preparation of Pb2+-ion-selective electrodes (ISEs)) and coupled with model heavy metal Pb2+-ISEs. It was found that the super-Nernstian response of Pb2+-ISEs was eliminated when 10 to 50 mg ml-1 of the ISM cocktail was used for the modification of paper substrates. The modification of the paper substrates by Pb2+-ISM allowed the elimination of adsorption sites. In addition, it resulted in an improvement of sensor performance in terms of their detection limits to be similar to those for conditioned electrodes in standard beaker-based measurements. It is believed that the elimination of super-Nernstian response of the electrodes and improving the potentiometric responses and detection limits of ISEs were attributed to the compatibility improvement of the paper substrates and Pb2+-ISEs to the same type of ISM.


Assuntos
Metais Pesados , Microfluídica , Eletrodos Seletivos de Íons , Chumbo , Potenciometria
5.
Anal Chim Acta ; 1197: 339495, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35168719

RESUMO

Metal modified paper-based substrates were utilized for microfluidic paper-based solution sampling coupled with Pb2+-ion selective electrodes (ISEs) with the aim of controlling the super-Nernstian response which usually occurs when using unmodified paper substrates. Potentiometric responses of Pb2+-ISEs coupled with gold, platinum and palladium coated paper substrates were investigated. Potentiometric response time was found to be predominantly dependent on the thickness of metallic layer deposited at the paper substrates. Paper-based substrates coated on both sides with 38 nm gold layers were found to be the most advantageous in controlling the super-Nernstian response of ISEs at non-equilibrium conditions. Durability studies indicated that the lifetime of Pb2+-ISEs could be doubled when used with paper-based substrates in complex environmental samples with high solid-to-liquid content. Determination of lead in real samples using metal modified paper substrates coupled with Pb2+-ISEs was validated by inductively coupled plasma optical emission spectrometry (ICP-OES). Detailed life cycle assessments were performed for model screen printed potentiometric sensors with and without metal modified paper-based solution sampling substrates. The results confirmed that the use of modified paper substrates demonstrated lower environmental impact per potentiometric measurement of Pb2+-ISE in prepared simulated environmental sample as compared to sensors without the use of paper substrates.


Assuntos
Metais Pesados , Microfluídica , Eletrodos Seletivos de Íons , Potenciometria
6.
Anal Chem ; 93(4): 1880-1888, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33430590

RESUMO

This Feature summarizes recent works in paper-based potentiometry and voltammetry in heavy metal determination. Interactions of paper substrates with heavy metals, influence on the sensing response, and modification methods applied to paper substrates to improve the performance of recently developed electrochemical sensors are discussed. Since the rekindling of interest in paper-based analytical devices, methodologies and electrode designs for heavy metal determinations are highlighted. Promising aspects of the use of these sensors for samples containing solids and the increased versatility of the use of paper in analytics offers the possibility of increased acceptance of these low-cost platforms.


Assuntos
Técnicas Eletroquímicas/métodos , Metais Pesados/química , Papel , Técnicas Eletroquímicas/economia , Técnicas Eletroquímicas/instrumentação , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos
7.
Anal Chim Acta ; 1128: 19-30, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32825902

RESUMO

Nano-layered solid-contact potassium-selective electrodes (K+-ISEs) were explored as model ion-selective electrodes for their practical use in clinical analysis. The ultra-thin ISEs ought to be manufactured in a highly reproducible manner, potentially making them suitable for mass production. Thus, their development is pivotal towards miniaturised sensors with simplified conditioning/calibration protocols for point-of-care diagnostics. To study nano-layered ISEs, the ultra-thin nature of ISEs for the first time enabled to combine potentiometry-quartz crystal microbalance with dissipation (QCM-D) to obtain value-added information on the ISE potentiometric response regarding their physical state such as mass/thickness/viscoelastic properties/structural homogeneity. Specifically, the studies were focused on real-time observations of the ISE potentiometric response in relation to changes of their physicochemical properties during the ISE preparation (conditioning) and operation (including biofouling conditions) to identify the occurring processes that may accordingly be critical for potential instability of the ISEs, impeding their practical application. The K+-ISEs were prepared on a QCM-D gold sensor by electrodepositing poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) layer serving as an ion-to-electron transducer subsequently covered by a spin-coated poly(vinyl chloride) based K+-ion selective membrane (K+-ISM). The studies demonstrated that the performance of the nano-layered design of K+-ISEs is detrimentally affected by such processes as water layer formation accordingly causing the instability of the electrode potential. The changes in the ISE physical state such mass/viscoelastic properties associated with water layer formation and origin of the potential instability was already observed at the ISE conditioning stage. The potential instability of nano-layered ISEs limits their practical applicability, indicating the need of new solutions in designing ISEs, for instance, exploiting new water-resistant materials and modifying preparation protocols.

8.
Anal Chim Acta ; 1091: 103-111, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31679563

RESUMO

This work demonstrates an application of the new materials, sponges, for the use in microfluidic solution sampling integrated with ion-selective electrodes. The microfluidic sponge-based sampling was developed and studied as novel sampling and sample handling method to serve as alternative for microfluidic paper- and textile-based sampling for ion analysis in various environmental (Cd2+, Pb2+ and pH) and clinically (K+, Na+, Cl-) relevant samples. Three types of polyurethane, cellulose and natural sponges were used as substrates for microfluidic solution sampling. Polyurethane based sponge was found to have low heavy metal sorption capacity thus it was recognized as suitable for microfluidic sampling coupled with solid-state as well as solid-contact ion-selective electrodes. The application of sponge-based microfluidic sampling, contrary to previous findings of paper- and textile-based microfluidic sampling, allowed measurements of heavy metals without prior modification of the sampling substrate. Finally, the determination of potassium, sodium and chloride in wastewater sludge and sweat samples done with sponge-based microfluidic sampling integrated with ISEs was found similar to analysis done by ICP-OES and IC.


Assuntos
Celulose/química , Cloretos/análise , Poliuretanos/química , Potássio/análise , Sódio/análise , Humanos , Eletrodos Seletivos de Íons , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Potenciometria/instrumentação , Potenciometria/métodos , Solo/química , Suor/química , Águas Residuárias/análise
9.
Biomed Pharmacother ; 96: 434-442, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29031202

RESUMO

The low median survival rate of oral squamous cell carcinoma (OSCC) is associated with chemotherapeutic resistance. Niclosamide is an oral anti-helminthic drug, its anti-cancer effect has been reported in recent years. However, the effect of niclosamide on OSCC remains largely unknown. In this study, we, for the first time, investigated the underlying mechanisms from cell cycle arrest and let-7a/STAT3 axis through CCK-8, cell cycle, apoptosis, wound healing, Transwell invasion, generation of stable cell line, real-time PCR, and western blot assays using two OSCC cell lines WSU-HN6 and Tca83. We showed that niclosamide could inhibit OSCC cells proliferation through causing cell cycle arrest in G1 phase and promoting apoptosis, while the cell cycle-related proteins MCM2, MCM7, CDK2 and CDK4 were downregulated and the apoptosis-related proteins p53 and cleaved caspase-3 were upregulated. Furthermore, niclosamide could inhibit migration and invasion of OSCC through upregulation of let-7a expression and downregulation of p-STAT3 expression. What is more, we established the stably expressing let-7a cell line (HN6-let-7a). Like niclosamide, HN6-let-7a could decrease the ability of the cell migration, invasion as well as the expression of p-STAT3. Collectively, our study finds the new mechanisms that niclosamide inhibits OSCC proliferation through causing cell cycle arrest in G1 phase via downregulation of the above cell cycle-related genes; promotes OSCC apoptosis through upregulation of pro-apoptotic genes; decreases migration and invasion of OSCC by let-7a/STAT3 axis, thus providing a preferred therapeutic candidate for OSCC in future.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Ciclo Celular/fisiologia , Movimento Celular/fisiologia , MicroRNAs/metabolismo , Neoplasias Bucais/metabolismo , Fator de Transcrição STAT3/metabolismo , Antinematódeos/administração & dosagem , Carcinoma de Células Escamosas/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos/métodos , Humanos , Neoplasias Bucais/patologia , Niclosamida/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
10.
Connect Tissue Res ; 57(1): 38-43, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26577469

RESUMO

PURPOSE OF THE STUDY: Follicular dendritic cell-secreted protein (FDC-SP) has been found to be expressed in periodontal ligament (PDL), a layer of soft connective tissue between tooth root and alveolar bone, and involved in immunoreaction. This study was performed to explore the potential role of FDC-SP in periodontal disease. MATERIALS AND METHODS: The human periodontal ligament cells (hPDLCs) were stimulated with Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide (LPS) and FDC-SP expression was examined by real-time PCR and western blot. Then this molecule was overexpressed or silenced in hPDLCs by transfection of FDC-SP expression plasmids or its small-interfering (si) RNA, respectively, and the effects of FDC-SP on expression of osteogenesis- and osteoclastogenesis-related genes in hPDLCs were analyzed by real-time PCR and western blot. RESULTS: Our results showed that P. gingivalis LPS upregulated FDC-SP expression in hPDLCs. Overexpression of FDC-SP could decrease the expression of osteogenesis-related genes, increase the expression of osteoclastogenesis-related genes and RANKL/OPG ratio in hPDLCs. Meanwhile, silence of FDC-SP expression in hPDLCs remarkably inversed the above results. CONCLUSIONS: LPS-induced upregulation of FDC-SP expression in hPDLCs may enhance osteoclastogenesis in periodontal disease.


Assuntos
Osteoclastos/metabolismo , Osteogênese , Doenças Periodontais/metabolismo , Ligamento Periodontal/metabolismo , Proteínas/metabolismo , Adulto , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Osteoclastos/patologia , Doenças Periodontais/patologia , Ligamento Periodontal/patologia , Porphyromonas gingivalis/química
11.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 22(6): 474-6, 2004 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-15656524

RESUMO

OBJECTIVE: To evaluate the possibility for removal of resinifying agent, time required for removal and the working length loss by Resosolv or Chloroform. METHODS: 40 human teeth (80 root canals) obturated with FR phenolaldehyde agent were divided into four groups, 20 root canals per group. Group A: Resosolv with K file; group B: chloroform with K file; group C: Resosolv with Ultrasonic K file; group D: Chloroform with ultrasonic K file. Calculating the pereentage for removal of resinifying agent, time required for removal and the working length loss. RESULTS: The effectiveness of Resosolv for removing resinifying agent was better than chloroform. 87.5% of canals could be negotiated by Resosolv; 45% of canals be negotiated by chloroform. CONCLUSION: Resosolv is an effective solvent for canals obturated with resinifying agent.


Assuntos
Clorofórmio/química , Materiais Restauradores do Canal Radicular/química , Solventes/química , Humanos , Retratamento , Obturação do Canal Radicular/métodos
12.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 38(2): 86-8, 2003 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-12839636

RESUMO

OBJECTIVE: To investigate prevalence, location, negotiation and the effect of operating microscope (OM) in the treatment of the second mesiobuccal canal (MB2) in maxillary molars. METHODS: 113 maxillary molars were studied. The crowns of the teeth were removed 1 mm above the chamber bottom for searching MB2 canal. Initially location and negotiation of MB2 canal were attempted without OM. Teeth in which MB2 canal were not located or negotiated were further explored under OM. Canal orifices including MB orifice, MB2 orifice and palatal orifice were filled by red gutta-percha cones, then the teeth were scanned by scanner. The images were analyzed by Image-Proplus 4.0 software to measure the relationship between MB2 canal and other canals. RESULTS: The MB-MB2 distance is (1.47 +/- 0.54) mm, MB-P distance is (5.77 +/- 0.66) mm, the vertical distance from MB2 to MB-P line is (0.53 +/- 0.28) mm, the angle between MB-P line and MB-MB2 line is 23.07 degrees +/- 13.08 degrees. MB2 orifices were located in 70 teeth (61.9%) and negotiated in 53 teeth (46.9%) without OM. With OM, additional MB2 orifices were located in other 6 teeth, 4 were negotiated; and 2 were negotiated in which MB2 canal were not negotiated without OM. CONCLUSIONS: MB2 canal can be located in 67.3% and negotiated in 52.2% of maxillary molars. Ability to locate and negotiate MB2 canal is facilitated by OM. The MB2 canal was located less than 1 mm mesially to the MB-P line and 2 mm palatally from the MB orifice.


Assuntos
Cavidade Pulpar/anatomia & histologia , Dente Molar/anatomia & histologia , Humanos , Maxila , Microscopia
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