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1.
J Colloid Interface Sci ; 674: 370-378, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38941931

RESUMO

Membrane technology holds great potential for separation applications and also finds critical needs in biomedical fields, such as blood oxygenation. However, the bottlenecks in gas permeation, plasma leakage, and especially hemocompatibility hamper the development of membrane oxygenation. It remains extremely challenging to design efficient membranes and elucidate underlying principles. In this study, we report biomimetic decoration of asymmetric nanoporous membranes by ultrathin FeIII-tannic acid metal-ligand networks to realize fast gas exchange with on plasma leakage and substantially enhance hemocompatibility. Because the intrinsic nanopores facilitate gas permeability and the FeIII-catechol layers enable superior hydrophilicity and electronegativity to original surfaces, the modified membranes exhibit high transport properties for gases and great resistances to protein adsorption, platelet activation, coagulation, thrombosis, and hemolysis. Molecular docking and density functional theory simulations indicate that more preferential adsorption of metal-ligand networks with water molecules than proteins is critical to anticoagulation. Moreover, benefiting from the better antiaging property gave by biomimetic decoration, the membranes after four-month aging present gas permeances similar to or even larger than those of pristine ones, despite the initial permeation decline. Importantly, for blood oxygenation, the designed membranes after aging show fast O2 and CO2 exchange processes with rates up to 28-17 and 97-47 mL m-2 min-1, respectively, accompanied with no detectable thrombus and plasma leakage. We envisage that the biomimetic decoration of nanoporous membranes provide a feasible route to achieve great biocompatibility and transport capability for various applications.

2.
Nat Commun ; 15(1): 164, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167389

RESUMO

Two-dimensional nanosheets, e.g., graphene oxide (GO), have been widely used to fabricate efficient membranes for molecular separation. However, because of poor transport across nanosheets and high width-to-thickness ratio, the permeation pathway length and tortuosity of these membranes are extremely large, which limit their separation performance. Here we report a facile, scalable, and controllable nanowire electrochemical concept for perforating and modifying nanosheets to shorten permeation pathway and adjust transport property. It is found that confinement effects with locally enhanced charge density, electric field, and hydroxyl radical generation over nanowire tips on anode can be executed under low voltage, thereby inducing confined direct electron loss and indirect oxidation to reform configuration and composition of GO nanosheets. We demonstrate that the porous GO nanosheets with a lot of holes are suitable for assembling separation membranes with tuned accessibility, tortuosity, interlayer space, electronegativity, and hydrophilicity. For molecular separation, the prepared membranes exhibit quadruple water permeance and higher rejections for salts (>91%) and small molecules (>96%) as/than original ones. This nanowire electrochemical perforation concept offers a feasible strategy to reconstruct two-dimensional materials and tune their transport property for separation.

3.
J Diabetes ; 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37864379

RESUMO

BACKGROUND: To compare glycemic control in Chinese patients with type 2 diabetes mellitus (T2DM) whose blood glucose levels were inadequately controlled with oral antidiabetic drugs after beinaglutide alone or combined with insulin glargine (IGlar). METHODS: In this 16-week multicenter, randomized clinical trial, 68 participants randomly received beinaglutide or IGlar for 8 weeks, then the two drugs in combination for 8 weeks. The primary outcomes were the proportion of individuals achieving their glycemic target and the change in glucose variability as measured with a continuous glucose monitoring system from baseline to 8 and 16 weeks. RESULTS: Both the beinaglutide and IGlar groups showed increased proportions achieving their glycemic target at 8 weeks, and the combination augmented the proportion reaching the glycated hemoglobin target from 25.42% at 8 weeks to 40.68% at 16 weeks. The beinaglutide group showed a significant reduction in body weight, body mass index, waist circumference, and systolic blood pressure. Beinaglutide elevated high-density lipoprotein cholesterol by 0.08 mmol/L (95% confidence interval [CI], 0.00-0.16), and diminished low-density lipoprotein cholesterol by 0.21 mmol/L (95% CI, 0.05-0.48), whereas IGlar showed no effect. Though IGlar was more efficient in lowering fasting plasma glucose than beinaglutide at comparable efficacies (to -1.57 mmol/L [95% CI, -2.60 to -0.54]), this difference was abolished in patients whose fasting C-peptide was ≥0.9 ng/mL. CONCLUSION: Beinaglutide exhibited a favorable hypoglycemic effect on patients with T2DM, and in combination with IGlar, glucose level was further decreased. Low fasting C-peptide in patients may reduce the glycemic response to beinaglutide therapy. We recommend that C-peptide levels be evaluated when using or switching to the novel glucagon-like peptide-1 receptor agonists beinaglutide. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03829891.

4.
Research (Wash D C) ; 6: 0151, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37214199

RESUMO

Membrane technology has attracted considerable attention for chemical and medical applications, among others. Artificial organs play important roles in medical science. A membrane oxygenator, also known as artificial lung, can replenish O2 and remove CO2 of blood to maintain the metabolism of patients with cardiopulmonary failure. However, the membrane, a key component, is subjected to inferior gas transport property, leakage propensity, and insufficient hemocompatibility. In this study, we report efficient blood oxygenation by using an asymmetric nanoporous membrane that is fabricated using the classic nonsolvent-induced phase separation method for polymer of intrinsic microporosity-1. The intrinsic superhydrophobic nanopores and asymmetric configuration endow the membrane with water impermeability and gas ultrapermeability, up to 3,500 and 1,100 gas permeation units for CO2 and O2, respectively. Moreover, the rational hydrophobic-hydrophilic nature, electronegativity, and smoothness of the surface enable the substantially restricted protein adsorption, platelet adhesion and activation, hemolysis, and thrombosis for the membrane. Importantly, during blood oxygenation, the asymmetric nanoporous membrane shows no thrombus formation and plasma leakage and exhibits fast O2 and CO2 transport processes with exchange rates of 20 to 60 and 100 to 350 ml m-2 min-1, respectively, which are 2 to 6 times higher than those of conventional membranes. The concepts reported here offer an alternative route to fabricate high-performance membranes and expand the possibilities of nanoporous materials for membrane-based artificial organs.

5.
Huan Jing Ke Xue ; 41(8): 3591-3600, 2020 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124332

RESUMO

Unmanned aerial vehicle (UAV) multispectral remote sensing can be used to monitor multiple water quality parameters, such as suspended solids, turbidity, total phosphorus, and chlorophyll. Establishing a stable and accurate water quality parameter inversion model is a prerequisite for this work. The matching pixel-by-pixel (MPP) algorithm is an inversion algorithm for high resolution features of UAV images; however, it is associated with problems of excessive computation and over-fitting. To overcome these problems, the optimize-MPP (OPT-MPP) algorithm is proposed. In this study, Qingshan Lake in Hangzhou City, Zhejiang Province, was used as the research area. Forty-five samples were collected to construct the OPT-MPP algorithm inversion model for two water quality parameters:the suspended sediments concentration (SS) and turbidity (TU). The results showed that the optimal suspended sediment concentration inversion model had a determination coefficient (R2) of 0.7870 and a comprehensive error of 0.1308. The optimal turbidity inversion model had a R2 of 0.8043 and a comprehensive error of 0.1503. Hence, the inversion of the spatial distribution information for water quality parameters in each experimental area of QingShan Lake was realized by using the optimal models of the two established parameters.


Assuntos
Tecnologia de Sensoriamento Remoto , Qualidade da Água , Algoritmos , Clorofila , Lagos
6.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(8): 750-756, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31638573

RESUMO

Objective To prepare and characterize the somatostatin (SS) anti-idiotypic antibody of yolk (SS yolk Ab2 ) on the basis of successful preparation of neutralizing SS mAb1 2E7, and then to further probe the application of SS yolk Ab2 in promoting animal growth. Methods The egg-laying hens were immunized with the neutralizing SS mAb1 2E7. The eggs containing a high titer of SS yolk Ab2 were collected and the egg yolk was separated from the egg white. The SS yolk Ab2 in yolk solution was extracted by water dilution and acidification, and was purified by precipitating with cool ethanol. The titer, concentration and specificity of SS yolk Ab2 was determined by ELISA. The Ab2ß property of SS yolk Ab2 was determined by ELISA of competitive inhibition. The effect of SS yolk Ab2 on animal growth was experimented in the mice, chickens and fish. Results The SS yolk Ab2 had a titer of 1×10-5 and a concentration of 8 mg/mL. The SS yolk Ab2 could react with the rabbit antibody against SS, but not react with the rabbit antibody against growth hormone, insulin and gastrin. The immunoreaction between the SS yolk Ab2 and rabbit antibody against SS was inhibited by SS competitively. The SS yolk Ab2 could induce the mouse to produce SS Ab3 and the SS Ab3 could react with SS, which suggest that the SS yolk Ab2 was an Ab2ß. The SS yolk Ab2 was used to immunize the mice in different doses of 0.8 µg or 3.2 µg each mouse by subcutaneous injection, and to immunize the chickens in different doses of 0.8 µg or 3.2 µg each chicken through intramuscular injection, and to immunize the Doppelfish in doses of 3.2 µg each Doppelfish by immersing fishes in 2 L of sea water containing Ab2. The control animals were immunized with the same volume of physiological saline and by the same methods. One month later, the SS yolk Ab2 vaccine could increase body weight 33.5% and 37.0% in the mice, 25.6% and 34.1% in chickens, and 24.8% in the Doppelfish compared with the corresponding controls. Conclusion The SS yolk Ab2 was prepared successfully. It had a high titer, concentration and specificity. It is an Ab2ß as a vaccine can increase body weight of animals significantly by small-dose immunization only once.


Assuntos
Anticorpos Anti-Idiotípicos , Galinhas , Gema de Ovo , Somatostatina , Animais , Anticorpos Anti-Idiotípicos/análise , Anticorpos Anti-Idiotípicos/metabolismo , Gema de Ovo/química , Ensaio de Imunoadsorção Enzimática , Feminino , Peixes , Crescimento/fisiologia , Imunização , Camundongos
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