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1.
PLoS One ; 16(10): e0258972, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34710141

RESUMO

INTRODUCTION: Ultrasound-guided tracheostomy (UGT) and bronchoscope-guided tracheostomy (BGT) have been well compared. However, the differences in benefits between UGT and landmark tracheostomy (LT) have not been addressed and, in particular, lack a detailed meta-analysis. We aimed to compare the first-pass success, complication rate, major bleeding rate, and tracheostomy procedure time between UGT and LT. METHODS: In a systematic review, relevant databases were searched for studies comparing UGT with LT in intubated patients. The primary outcome was the odds ratio (OR) of first-pass success. The secondary outcomes were the OR of complications, OR of major bleeding, and standardized mean difference (SMD) of the total tracheostomy procedure time. RESULTS: The meta-analysis included three randomized controlled studies (RCTs) and one nonrandomized controlled study (NRS), comprising 474 patients in total. Compared with LT, UGT increased first-pass success (OR: 4.287; 95% confidence interval [CI]: 2.308 to 7.964) and decreased complications (OR: 0.422; 95% CI: 0.249 to 0.718). However, compared with LT, UGT did not significantly reduce major bleeding (OR: 0.374; 95% CI: 0.112 to 1.251) or the total tracheostomy placement time (SMD: -0.335; 95% CI: -0.842 to 0.172). CONCLUSIONS: Compared with LT, real-time UGT increases first-pass success and decreases complications. However, UGT was not associated with a significant reduction in the major bleeding rate. The total tracheostomy placement time comparison between UGI and LT was inconclusive.


Assuntos
Broncoscopia/métodos , Traqueostomia/métodos , Ultrassonografia de Intervenção/métodos , Pontos de Referência Anatômicos , Broncoscopia/efeitos adversos , Humanos , Cooperação Internacional , Complicações Pós-Operatórias/etiologia , Traqueostomia/efeitos adversos , Ultrassonografia de Intervenção/efeitos adversos
3.
PLoS One ; 10(12): e0145542, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26713735

RESUMO

Human mesenchymal stem cells (MSCs) modified by targeting DNA hypermethylation of genes in the Salvador/Warts/Hippo pathway were induced to differentiate into neuronal cells in vitro. The differentiated cells secreted a significant level of brain-derived neurotrophy factor (BDNF) and the expression of BDNF receptor tyrosine receptor kinase B (TrkB) correlated well with the secretion of BDNF. In the differentiating cells, CREB was active after the binding of growth factors to induce phosphorylation of ERK in the MAPK/ERK pathway. Downstream of phosphorylated CREB led to the functional maturation of differentiated cells and secretion of BDNF, which contributed to the sustained expression of pERK and pCREB. In summary, both PI3K/Akt and MAPK/ERK signaling pathways play important roles in the neuronal differentiation of MSCs. The main function of the PI3K/Akt pathway is to maintain cell survival during neural differentiation; whereas the role of the MAPK/ERK pathway is probably to promote the maturation of differentiated MSCs. Further, cellular levels of protein kinase C epsilon type (PKC-ε) and kinesin heavy chain (KIF5B) increased with time of induction, whereas the level of NME/NM23 nucleoside diphosphate kinase 1 (Nm23-H1) decreased during the time course of differentiation. The correlation between PKC-ε and TrkB suggested that there is cross-talk between PKC-ε and the PI3K/Akt signaling pathway.


Assuntos
Diferenciação Celular , Metilação de DNA , Regulação da Expressão Gênica , Células-Tronco Mesenquimais/citologia , Neurônios/citologia , Transdução de Sinais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas de Ciclo Celular/metabolismo , Sobrevivência Celular , Via de Sinalização Hippo , Humanos , Neurônios/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo
4.
Rapid Commun Mass Spectrom ; 25(3): 410-4, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21213359

RESUMO

For the first time, we observed a stable and intense ion (m/z 376) of the oxygenated water cluster ion ((H(2)O)(20)O(+)) produced from simply spraying an aqueous solution of iron nanoparticles (Fe NPs) into an electrospray mass spectrometry (ESI-MS) system. Tandem mass spectrometric (MS/MS and MS/MS/MS) results were applied to identify the assignments of the fragment ions of m/z 376 in order to explore the possible structures of this cluster ion. The possible structures of the (H(2)O)(20)O(+) ions are proposed as pentagonal dodecahedron water clathrate cages from the results of tandem mass spectrometry since eliminations of five water molecules were frequently observed in the MS/MS results for many subsequent fragment ions of m/z 376. The formation of this oxygenated water cluster ion ((H(2)O)(20)O(+)) in ESI-MS is attributed to the high surface reactivity and surface energy of Fe NPs during ESI processes (under high temperature and high voltage (5 kV) of ESI spray environment). We believe that the observation of self-assembly formation of oxygenated water clusters is an important issue in nanoscience as well as in the fields of water clusters.


Assuntos
Nanoestruturas/química , Oxigênio/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Água/química , Ferro , Nanopartículas Metálicas
5.
Rapid Commun Mass Spectrom ; 25(2): 307-15, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-21192026

RESUMO

Single drop microextraction (SDME) coupled with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been applied for direct analysis of hydrophobic peptides (valinomycin and gramicidin D) from biological samples (urine and plasma) in high salt solution. The optimal conditions such as selection of extraction solvent, stirring rate, extraction time, effect of salt concentration and matrix-to-analyte ratio were investigated. The limits of detection (LODs) were found to be 73 nM to 170 nM for valinomycin and 96 nM to 5.5 µM for gramicidin D in high salt solution (1.7 M of NaCl) in MALDI-MS. The current approach can enhance the LODs by 11-320-fold for gramicidin D analysis in water, urine and plasma in high salt solution. Furthermore, the current approach has been successfully demonstrated for real-world sample analysis (ß-carotene from carrots) by MALDI-MS. The current approach is a rapid, simple and efficient clean-up platform for direct analysis of hydrophobic molecules in biological samples from high salt solution.


Assuntos
Fracionamento Químico/métodos , Gramicidina/análise , Cloreto de Sódio/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Valinomicina/análise , Gramicidina/sangue , Gramicidina/urina , Interações Hidrofóbicas e Hidrofílicas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Valinomicina/sangue , Valinomicina/urina
6.
Rapid Commun Mass Spectrom ; 20(16): 2511-5, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16862620

RESUMO

This study presents the feasibility of direct coupling of the immersed single-drop microextraction (SDME) technique with atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry (AP-MALDI-MS) for the rapid analysis of a hydrophilic drug (dopamine) from aqueous solution and human urine in an ion trap tandem mass spectrometer through hydrogen-bonding interaction of dopamine with the extraction solvent (octanol). The optimum conditions for the SDME experiments coupled to AP-MALDI/MS were: stirring rate, 240 rpm; extraction time, 5 min; sample pH value, 8; and matrix concentration, 2000 ppm, using alpha-cyano-4-hydroxycinnamic acid (alpha-CHCA) as matrix. The limits of detection (LODs) for the SDME/AP-MALDI-MS experiments were 25 and 40 ppm in water and human urine, respectively. In a comparison of this method with the traditional liquid-liquid extraction (LLE), the SDME method shows better LODs than the LLE (40 ppm) and the same LODs (25 ppm) as the liquid-phase microextraction using a dual gauge microsyringe with a hollow fiber (LPME/DGM-HF). However, the SDME method is more convenient than the LPME/DGM-HF method.


Assuntos
Fracionamento Químico/métodos , Dopamina/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massas em Tandem/métodos , Pressão Atmosférica , Ligação de Hidrogênio
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