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1.
Crit Care Med ; 52(3): e121-e131, 2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38156913

RESUMEN

OBJECTIVES: The association between protein intake and the need for mechanical ventilation (MV) is controversial. We aimed to investigate the associations between protein intake and outcomes in ventilated critically ill patients. DESIGN: Analysis of a subset of a large international point prevalence survey of nutritional practice in ICUs. SETTING: A total of 785 international ICUs. PATIENTS: A total of 12,930 patients had been in the ICU for at least 96 hours and required MV by the fourth day after ICU admission at the latest. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We modeled associations between the adjusted hazard rate (aHR) of death in patients requiring MV and successful weaning (competing risks), and three categories of protein intake (low: < 0.8 g/kg/d, standard: 0.8-1.2 g/kg/d, high: > 1.2 g/kg/d). We compared five different hypothetical protein diets (an exclusively low protein intake, a standard protein intake given early (days 1-4) or late (days 5-11) after ICU admission, and an early or late high protein intake). There was no evidence that the level of protein intake was associated with time to weaning. However, compared with an exclusively low protein intake, a standard protein intake was associated with a lower hazard of death in MV: minimum aHR 0.60 (95% CI, 0.45-0.80). With an early high intake, there was a trend to a higher risk of death in patients requiring MV: maximum aHR 1.35 (95% CI, 0.99-1.85) compared with a standard diet. CONCLUSIONS: The duration of MV does not appear to depend on protein intake, whereas mortality in patients requiring MV may be improved by a standard protein intake. Adverse effects of a high protein intake cannot be excluded.


Asunto(s)
Respiración Artificial , Desconexión del Ventilador , Humanos , Enfermedad Crítica/terapia , Unidades de Cuidados Intensivos , Hospitalización
2.
J Org Chem ; 88(21): 15106-15117, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37864558

RESUMEN

A metal-free one-pot oxidative cross-dehydrogenation coupling reaction for the formation of C-N/C-C bonds at the C2,3-positions of indoles with azoles and quinoxalinones has been developed. The proposed method has several notable features, including metal-free catalysis, the use of N-H free indoles as substrates, ease of operation, mild reaction conditions, and compatibility with a wide range of substrates.

3.
Comput Intell Neurosci ; 2022: 1633946, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36313052

RESUMEN

With the development of neuromorphic computing, more and more attention has been paid to a brain-inspired spiking neural network (SNN) because of its ultralow energy consumption and high-performance spatiotemporal information processing. Due to the discontinuity of the spiking neuronal activation function, it is still a difficult problem to train brain-inspired deep SNN directly, so SNN has not yet shown performance comparable to that of an artificial neural network. For this reason, the spike-based approximate backpropagation (SABP) algorithm and a general brain-inspired SNN framework are proposed in this paper. The combination of the two can be used for end-to-end direct training of brain-inspired deep SNN. Experiments show that compared with other spike-based methods of directly training SNN, the classification accuracy of this method is close to the best results on MNIST and CIFAR-10 datasets and achieves the best classification accuracy on sonar image target classification (SITC) of small sample datasets. Further analysis shows that compared with artificial neural networks, our brain-inspired SNN has great advantages in computational complexity and energy consumption in sonar target classification.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Encéfalo/fisiología , Neuronas/fisiología
4.
J Pharm Biomed Anal ; 195: 113869, 2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33401116

RESUMEN

An 1H NMR-based metabolomics approach was conducted to holisticly explore the effect of Xue Fu Zhu Yu (XFZY) capsule (a well-known Chinese herbal medicine) on high-fat diets combined with coronary artery ligation induced coronary heart disease (CHD) model rats. 1H NMR-based metabolomics approach combined with multivariate analysis was performed to explore potential biomarkers, a total of 20 metabolites were confirmed as contributors to the discrimination of model group and sham group. We investigated the dynamic metabolic characteristics of XFZY capsule on CHD rats, lactate, glutamine, pyruvate, citrate, choline and taurine were potential biomarkers of early effect. More potential biomarkers changed after 28 days of medication, XFZY capsules primarily influenced the taurine and hypotaurine metabolism, glycine, serine and threonine metabolism, glyoxylate and dicarboxylate metabolism, purine metabolism, glycolysis/gluconeogenesis, amino sugar and nucleotide sugar metabolism, primary bile acid biosynthesis.


Asunto(s)
Enfermedad Coronaria , Medicamentos Herbarios Chinos , Animales , Cápsulas , Vasos Coronarios , Dieta Alta en Grasa/efectos adversos , Metabolómica , Espectroscopía de Protones por Resonancia Magnética , Ratas
5.
Phys Chem Chem Phys ; 22(3): 1655-1664, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31894788

RESUMEN

Layered double hydroxide-supported Au-Cu alloy nanoparticles (NPs) were found to be highly efficient catalysts for the oxidative esterification of benzyl alcohol with methanol in the presence of molecular oxygen under visible-light irradiation to prepare methyl benzoate. Here, we report that alloying small amounts of copper into gold nanoparticles can increase the ability to activate oxygen molecules to O2˙- radicals and display greater charge heterogeneity to promote the cleavage of the C-H bond of benzyl alcohol molecules by reinforcing the coordination of the intermediate with unsaturated metal active sites due to the LSPR effect of alloy NPs, which is the rate-limiting step of the reaction. Besides the Au-Cu alloy NPs, the support also played a pivotal role in the catalytic process. The support with the presence of acid-base pairs, in which the basic sites served as the reactant molecule adsorption sites to provoke the intermediate formation and the acidic sites promoted the recovery of the support surface, showed better performances by affecting the overall reaction rate completely. Moreover, applying this photocatalyst in the cross-esterification of aromatic alcohols and aliphatic alcohols displayed excellent yields.

6.
Nanomaterials (Basel) ; 10(1)2019 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-31877687

RESUMEN

Sheaf-like CeO2 (CeO2-S) in microscale was prepared by the hydrothermal method, and then etched with KOH aiming to obtain an imperfect fluorite structure (CeO2-SK) with high content of oxygen vacancies and oxygen mobility. With CeO2-S and CeO2-SK as supports respectively, a modified colloidal deposition method was employed to obtain Pd/CeO2 catalysts for being used in lean methane combustion. According to the inductively coupled plasma (ICP), N2 physisorption and scanning electron microscopy (SEM) results, the Pd supported catalysts are very similar in their Pd loading, surface area and morphologies. SEM and transmission electron microscopy (TEM) results revealed various nanorods exposed CeO2 (110) and (100) facets on Pd/CeO2-SK surface after KOH etching. Raman spectra and H2-temperature programmed reduction (H2-TPR) results indicated that Pd/CeO2-SK catalyst has a much higher content of catalytic active PdO species than Pd/CeO2-S catalyst. It was also found that the catalytic performance of Pd/CeO2 in lean methane combustion depends greatly upon the exposing crystal planes and oxygen vacancies content of sheaf-like CeO2, and Pd/CeO2-SK exhibits higher activity than Pd/CeO2-S. The larger amount of CeO2 (110) and (100) planes on Pd/CeO2-SK surface can enhance the formation of oxygen vacancies, active Pd species and migration of lattice oxygen, which all evidently improve the redox ability and catalytic activity of the Pd/CeO2-SK catalysts in lean methane combustion.

7.
Chem Commun (Camb) ; 53(98): 13165-13167, 2017 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-29177297

RESUMEN

A flexible Sb2O3/carbon cloth (CC) composite is synthesized using a simple solvothermal method. The Sb2O3/CC composite exhibits higher capacity and capacity retention of alloying and conversion reactions as an anode for sodium ion batteries, attributed to the good conductivity of CC and strong chemical bonds between Sb2O3 and CC.

8.
J Neuroimmunol ; 301: 41-48, 2016 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-27836178

RESUMEN

HIV infection is persistent in the CNS, to evaluate the compartmentalization of the CNS immune response to HIV, we compared soluble markers of cellular immunity in the blood and CSF among HIV- (n=19) and HIV+ (n=68), as well as among HIV participants with or without CSF pleocytosis. Dysfunction of the blood cerebrospinal fluid barrier (BCSFB) was common in HIV participants. CSF levels of TNFα, IFNγ, IL-2, IL-6, IL-7, IL-10, IP-10, MIP-1α, MIP-1ß, and RANTES were significantly higher in participants with CSF pleocytosis (P<0.05); serum levels of these biomarkers were comparable. The CNS immune response is compartmentalized, and remains so despite the BCSFB dysfunction during HIV infection; it is markedly reduced by virology suppression, although BCSFB dysfunction persists on this subgroup.


Asunto(s)
Barrera Hematoencefálica/patología , Sistema Nervioso Central/patología , Citocinas/sangre , Citocinas/líquido cefalorraquídeo , Infecciones por VIH , Adulto , Estudios Transversales , Femenino , Infecciones por VIH/líquido cefalorraquídeo , Infecciones por VIH/metabolismo , Infecciones por VIH/patología , VIH-1/genética , Humanos , Masculino , Persona de Mediana Edad , ARN/líquido cefalorraquídeo
9.
J Ethnopharmacol ; 185: 60-7, 2016 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-26976764

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Yinchenwuling Powder (YCL) is a traditional Chinese medicine formula originated from Synopsis of Golden Chamber, which is effective in positively modulating lipid levels in clinics. In this study, we utilized proteomic technology to identify the therapeutic targets of YCL on hyperlipidemic rats. METHODS: We established hyperlipidemic model rats and administrated them with different doses of YCL extracts (0.35g/ml, 0.75g/ml and 1.5g/ml). Serum lipid levels were quantified and proteomic analysis was performed on plasma samples at the end of the study. Total plasma proteins were separated by two-dimensional electrophoresis (2-DE), and protein spots with 1.5-fold difference were excised and then analyzed by MALDI-TOF MS. Proteomic results were verified by Western blotting. RESULTS: The results showed that the serum levels of TC, TG, and LDL-C were significantly decreased, while the HDL-C levels were significantly increased in different doses of YCL treatment groups. After being analyzed by 2-DE and MALDI-TOF MS, 12 proteins were identified. Eight proteins (T-kininogen, C3, C4, C4BPA, Igλ-2 chain C, Mbl2, Hpx and FGL1) were up-regulated in hyperlipidemic model rats, while four proteins (ApoE, ALB, TTR and VDBP) were up-regulated in the control and the YCL-treated rats. Two plasma proteins, ApoE and FGL1, involved in lipid metabolism, were confirmed by western blotting, and the results were consistent with the data from the proteomics results. CONCLUSIONS: In this experiment, we identified 12 differentially-expressed plasma proteins associated with therapeutic effects of YCL. The functions of those proteins are related with lipid metabolism, blood coagulation, anti-inflammation and substance transport. This study provided a clue for the mechanism that underlies the therapeutic effect of YCL on lipid metabolism.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Hiperlipidemias/tratamiento farmacológico , Proteómica , Animales , Electroforesis en Gel Bidimensional , Lípidos/sangre , Medicina Tradicional China , Ratas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
10.
Comput Math Methods Med ; 2015: 598415, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26417380

RESUMEN

We study the deformation and haptic feedback of soft tissue in virtual surgery based on a liver model by using a force feedback device named PHANTOM OMNI developed by SensAble Company in USA. Although a significant amount of research efforts have been dedicated to simulating the behaviors of soft tissue and implementing force feedback, it is still a challenging problem. This paper introduces a kind of meshfree method for deformation simulation of soft tissue and force computation based on viscoelastic mechanical model and smoothed particle hydrodynamics (SPH). Firstly, viscoelastic model can present the mechanical characteristics of soft tissue which greatly promotes the realism. Secondly, SPH has features of meshless technique and self-adaption, which supply higher precision than methods based on meshes for force feedback computation. Finally, a SPH method based on dynamic interaction area is proposed to improve the real time performance of simulation. The results reveal that SPH methodology is suitable for simulating soft tissue deformation and force feedback calculation, and SPH based on dynamic local interaction area has a higher computational efficiency significantly compared with usual SPH. Our algorithm has a bright prospect in the area of virtual surgery.


Asunto(s)
Modelos Anatómicos , Procedimientos Quirúrgicos Operativos/educación , Interfaz Usuario-Computador , Animales , Fenómenos Biomecánicos , Simulación por Computador , Elasticidad , Retroalimentación Fisiológica , Análisis de Elementos Finitos , Humanos , Hidrodinámica , Internado y Residencia , Hígado/cirugía , Fantasmas de Imagen , Viscosidad
11.
Chem Commun (Camb) ; 49(74): 8250-2, 2013 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-23925488

RESUMEN

Graphene supported Au-Pd bimetallic nanoparticles exhibit high catalytic activity in methanol selective oxidation, with a methanol conversion of 90.2% and selectivity of 100%, to methyl formate at 70 °C, owing to the synergism of Au and Pd particles as well as the strong interaction between graphene and Au-Pd nanoparticles.

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