Electrospun polyvinyl alcohol/carbon dioxide modified polyethyleneimine composite nanofiber scaffolds

A novel biocompatible polyvinyl alcohol/carbon dioxide modified polyethyleneimine (PVA/PEI-CO2) composite nanofiber was fabricated by a green and facile protocol, which reduces the cytotoxicity of PEI through the surface modification of the PEI with CO2. The 13C NMR spectrum, elemental analysis, and TGA show that CO2 has been incorporated in the PEI surface resulting in a relatively stable structure. The resulting PVA/PEI-CO2 composite nanofibers have been characterized by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), contact angle, and scanning electron microscopy (SEM). The results show that the average diameters of the nanofibers range from 265 ± 53 nm to 423 ± 80 nm. The cytotoxicity of PVA/PEI-CO2 composite nanofibers was assessed by cytotoxicity evaluation using the growth and cell proliferation of normal mice Schwann cells. SEM and the MTT assay demonstrated the promotion of cell growth and proliferation on the PVA/PEI-CO2 composite scaffold. It suggests that PEI-CO2 can have tremendous potential applications in biological material research

Biased compensation recursive least squares-based threshold algorithm for time-delay rational models via redundant rule

© 2017, Springer Science+Business Media B.V., part of Springer Nature. This paper develops a biased compensation recursive least squares-based threshold algorithm for a time-delay rational model. The time-delay rational model is transformed into an augmented model by using the redundant rule, and then, a recursive least squares algorithm is proposed to estimate the parameters of the augmented model. Since the output of the augmented model is correlated with the noise, a biased compensation method is derived to eliminate the bias of the parameter estimates. Furthermore, based on the structures of the augmented model parameter vector and the rational model parameter vector, the unknown time delay can be computed by using a threshold given in prior. A simulated example is used to illustrate the efficiency of the proposed algorithm

Experimental Test of Tracking the King Problem

In quantum theory, the retrodiction problem is not as clear as its classical counterpart because of the uncertainty principle of quantum mechanics. In classical physics, the measurement outcomes of the present state can be used directly for predicting the future events and inferring the past events which is known as retrodiction. However, as a probabilistic theory, quantum-mechanical retrodiction is a nontrivial problem that has been investigated for a long time, of which the Mean King Problem is one of the most extensively studied issues. Here, we present the first experimental test of a variant of the Mean King Problem, which has a more stringent regulation and is termed "Tracking the King". We demonstrate that Alice, by harnessing the shared entanglement and controlled-not gate, can successfully retrodict the choice of King's measurement without knowing any measurement outcome. Our results also provide a counterintuitive quantum communication to deliver information hidden in the choice of measurement.Comment: 16 pages, 5 figures, 2 table

Mitigation of chronic unpredictable stress–induced cognitive deficits in mice by Lycium barbarum L (Solanaceae) polysaccharides

Purpose: To investigate the neuroprotective effects of Lycium barbarum polysaccharide (LBP) against concomitant cognitive dysfunction and changes in hippocampal CREB-BDNF signaling pathway in chronically unpredictable stressed mice.Methods: The mice were subjected to different unpredictable stressors for a period of 4 weeks. Behavioral tests, including open field (OFT) and Morris water maze (MWMT) tests were used to evaluate pharmacological effects. Serum corticosterone levels, protein expression level of BDNF and pCREB/CREB in hippocampus were assessed by ELISA, Western blot and immunohistochemistry methods, respectively. Morphological changes in pyramidal neurons in the hippocampus were studied by Nissl staining.Results: LBP improved mice performance in MWMT, indicating that it reversed chronic unpredictable stress (CUS)-induced cognitive deficits. LBP treatment reduced serum corticosterone levels and prevented neuron loss in the hippocampus. It maintained expression levels of BDNF and phosphorylation of CREB in hippocampus during CUS procedure.Conclusion: Lycium barbarum polysaccharide protects CREB-BDNF signaling pathway in hippocampus and relieves CUS-induced cognitive deficits. These results suggest that Lycium barbarum polysaccharides is potentially an alternative neuro-protective agent against stress-induced psychopathological dysfunction.Keywords: Lycium barbarum, Polysaccharide, Chronic unpredictable stress, Cognitive deficits, Brainderived neurotrophic factor, Calcium/cyclic-AMP responsive binding protei

Erythromycin Enhances CD4+Foxp3+ Regulatory T-Cell Responses in a Rat Model of Smoke-Induced Lung Inflammation

Heavy smoking can induce airway inflammation and emphysema. Macrolides can modulate inflammation and effector T-cell response in the lungs. However, there is no information on whether erythromycin can modulate regulatory T-cell (Treg) response. This study is aimed at examining the impact of erythromycin on Treg response in the lungs in a rat model of smoking-induced emphysema. Male Wistar rats were exposed to normal air or cigarette smoking daily for 12 weeks and treated by gavage with 100 mg/kg of erythromycin or saline daily beginning at the forth week for nine weeks. The lung inflammation and the numbers of inflammatory infiltrates in bronchoalveolar lavage fluid (BALF) were characterized. The frequency, the number of Tregs, and the levels of Foxp3 expression in the lungs and IL-8, IL-35, and TNF-α in BALF were determined by flow cytometry, RT-PCR and ELISA, respectively. Treatment with erythromycin reduced smoking-induced inflammatory infiltrates, the levels of IL-8 and TNF-α in the BALF and lung damages but increased the numbers of CD4+Foxp3+ Tregs and the levels of Foxp3 transcription in the lungs, accompanied by increased levels of IL-35 in the BALF of rats. Our novel data indicated that erythromycin enhanced Treg responses, associated with the inhibition of smoking-induced inflammation in the lungs of rats

A Thermostable β-Glucuronidase Obtained by Directed Evolution as a Reporter Gene in Transgenic Plants

A β-glucuronidase variant, GUS-TR3337, that was obtained by directed evolution exhibited higher thermostability than the wild-type enzyme, GUS-WT. In this study, the utility of GUS-TR337 as an improved reporter was evaluated. The corresponding gus-tr3337 and gus-wt genes were independently cloned in a plant expression vector and introduced into Arabidopsis thaliana. With 4-MUG as a substrate, plants containing the gus-wt gene showed no detectable β-glucuronidase activity after exposure to 60°C for 10 min, while those hosting the gus-tr3337 gene retained 70% or 50% activity after exposure to 80°C for 10 min or 30 min, respectively. Similarly, in vivo β-glucuronidase activity could be demonstrated by using X-GLUC as a substrate in transgenic Arabidopsis plants hosting the gus-tr3337 gene that were exposed to 80°C for up to 30 min. Thus, the thermostability of GUS-TR3337 can be exploited to distinguish between endogenous and transgenic β-glucuronidase activity, which is a welcome improvement in its use as a reporter