Multiperformance PAM/PVA/CaCO3 Hydrogel for Flexible Sensing and Information Encryption.

Currently, the development of hydrogels with excellent mechanical properties (elasticity, fatigue resistance, etc.) and conductive properties can better meet their needs in the field of flexible sensor device applications. Generally, hydrogels with a denser cross-linking density tend to have better mechanical properties, but the improvement in mechanical properties comes at the expense of reduced electrical conductivity. Directly generating CaCO3 in the hydrogel prepolymer can not only increase the cross-linking density of its network but also introduce additional ions to enhance its internal ionic strength, which is beneficial to improving the conductivity of the hydrogel. It is still a big challenge to directly generate CaCO3 in the static prepolymer solution and ensure its uniform dispersion in the hydrogel. Herein, we adopted an improved preparation method to ensure that the directly generated CaCO3 particles can be evenly dispersed in the static prepolymer solution until the polymerization is completed. Finally, a PAM/PVA/CaCO3 hydrogel with supertensile, compressive, toughness, and fatigue resistance properties was prepared. In addition, the presence of free Na+ and Cl- gives the hydrogel excellent conductivity and sensing performance to monitor daily human activities. On the basis of the application of hydrogels in information communication, we have further deepened this application by combining the characteristics of hydrogels themselves. Combined with ASCII code, the hydrogel can also be applied in information exchange and information encryption and decryption, achieving the antitheft function in smart locks. A variety of excellent performance integrated PAM/PVA/CaCO3 hydrogels have broad application prospects for flexible sensors, highlighting great potential in human-computer interaction and intelligent information protection.

Identification and validation of biomarkers based on cellular senescence in mild cognitive impairment.

Background: Mild cognitive impairment (MCI), a syndrome defined as decline of cognitive function greater than expected for an individual's age and education level, occurs in up to 22.7% of elderly patients in United States, causing the heavy psychological and economic burdens to families and society. Cellular senescence (CS) is a stress response that accompanies permanent cell-cycle arrest, which has been reported to be a fundamental pathological mechanism of many age-related diseases. This study aims to explore biomarkers and potential therapeutic targets in MCI based on CS. Methods: The mRNA expression profiles of peripheral blood samples from patients in MCI and non-MCI group were download from gene expression omnibus (GEO) database (GSE63060 for training and GSE18309 for external validation), CS-related genes were obtained from CellAge database. Weighted gene co-expression network analysis (WGCNA) was conducted to discover the key relationships behind the co-expression modules. The differentially expressed CS-related genes would be obtained through overlapping among the above datasets. Then, pathway and GO enrichment analyses were performed to further elucidate the mechanism of MCI. The protein-protein interaction network was used to extract hub genes and the logistic regression was performed to distinguish the MCI patients from controls. The hub gene-drug network, hub gene-miRNA network as well as transcription factor-gene regulatory network were used to analyze potential therapeutic targets for MCI. Results: Eight CS-related genes were identified as key gene signatures in MCI group, which were mainly enriched in the regulation of response to DNA damage stimulus, Sin3 complex and transcription corepressor activity. The receiver operating characteristic curves of logistic regression diagnostic model were constructed and presented great diagnostic value in both training and validation set. Conclusion: Eight CS-related hub genes - SMARCA4, GAPDH, SMARCB1, RUNX1, SRC, TRIM28, TXN, and PRPF19 - serve as candidate biomarkers for MCI and display the excellent diagnostic value. Furthermore, we also provide a theoretical basis for targeted therapy against MCI through the above hub genes.

Diversification and historical demography of Haloxylon ammodendron in relation to Pleistocene climatic oscillations in northwestern China.

The influence of aridification and climatic oscillations on the genetic diversity and evolutionary processes of organisms during the Quaternary in northwestern China is examined using Haloxylon ammodendron. Based on the variation of two cpDNA regions (trnS-trnG and trnV) and one nDNA sequence (ITS1-ITS4) in 420 individuals from 36 populations, the spatial genetic structure and demographic history of H. ammodendron in arid China is examined. Median-joining network and Bayesian inference trees enabled the identification of three diverged lineages within H. ammodendron from 24 different haplotypes and 16 ribotypes, distributed across western (Xinjiang), eastern (Gansu and Inner Mongolia) and southern (Qinghai) regions. AMOVA analysis demonstrated that more than 80% of observed genetic variation related to lineage split was based on cpDNA and nDNA variation. Allopatric divergence among the three groups was mainly triggered by geographical isolation due to Xingxingxia rock and uplift of the Qilian Mountains during the Quaternary. Local adaptive differentiation among western, eastern and southern groups occurred due to gene flow obstruction resulting from arid landscape fragmentation accompanied by local environmental heterogeneity of different geographical populations. The southern margin of the Junggar Basin and the Tengger Desert possibly served as two independent glacial refugia for H. ammodendron. The distribution of genetic variation, coupled with SDMs and LCP results, indicated that H. ammodendron probably moved northward along the Junggar Basin and westward along Tengger Desert at the end of the last glacial maximum; postglacial re-colonization was probably westward and southward along the Hexi Corridor.

Phylogeography of Amygdalus mongolica in relation to Quaternary climatic aridification and oscillations in northwestern China.

Quaternary period geological events and climatic oscillations significantly affect the geographic structure and genetic diversity of species distribution in arid northwestern China. Amygdalus mongolica is a relict and endangered shrub that occurs primarily in arid areas of northwestern China. Based on variation patterns present at three cpDNA regions (psbK-psbI, trnL-trnF and trnV) and in one nDNA sequence (ITS1-ITS4) in 174 individuals representing 15 populations, the spatial genetic structure and demographic history of A. mongolica was examined across its entire geographic range. The 17 different haplotypes and 10 ribotypes showed two lineages, distributed across the Western (Mazong Mountains, Hexi Corridor, and Alxa Left Banner) and Eastern regions (Urad Houqi, Yinshan Mountains, Urad Zhongqi, and Daqing Mountains) according to the median-joining network and the BI (Bayesian inference) and ML (Maximum likelihood) trees. AMOVA analysis demonstrated that over 65% of the observed genetic variation was related to this lineage split. The expansions of the Ulanbuhe and Tengger deserts and the eastward extension of the Yinshan Mountains since the Quaternary period likely interrupted gene flow and triggered the observed divergence in the two allopatric regions; arid landscape fragmentation accompanied by local environmental heterogeneity further increased local adaptive differentiation between the Western and Eastern groups. Based on the evidence from phylogeographical patterns and the distribution of genetic variation, A. mongolica distributed in the eastern and western regions are speculated to have experienced eastward migration along the southern slopes of the Lang Mountains and westward migration along the margins of the Ulanbuhe and Tengger deserts to the Hexi Corridor, respectively. For setting a conservation management plan, it is recommended that the south slopes of the Lang Mountains and northern Helan Mountains be identified as the two primary conservation areas, as they have high genetic variation and habitats that are more suitable.

Single network double cross-linker (SNDCL) hydrogels with excellent stretchability, self-recovery, adhesion strength, and conductivity for human motion monitoring.

Hydrogels, as a kind of soft materials, are good candidates for smart skin-like materials. A double network is usually fabricated to improve the mechanical properties of hydrogels, and involves two different kinds of networks. In this work, a novel strategy for preparing single network double cross-linker (SNDCL) hydrogels was proposed and the prepared hydrogels exhibited excellent mechanical properties, including stretchability, compressibility, self-recovery, adhesion, shape memory and mechanical strength. N,N'-Methylenebisacrylamide forms covalent bonds with the network, while citric acid can form multiple weak interactions due to the polycarboxylic structure. This improves the tensile properties (6564%) and compressive properties of the hydrogel, and the hydrogels also exhibit long-lasting self-adhesion ability on various substrates. In addition, the hydrogels with multiple properties can be used as flexible strain sensors, allowing the monitoring of body movements. The hydrogels can hopefully be used in wearable electronic sensor devices and for healthcare monitoring.

Temperature and H2O2-operated nano-valves on mesoporous silica nanoparticles for controlled drug release and kinetics.

Temperature and H2O2 dual-responsive nanoparticles were fabricated from ferrocene modified mesoporous silica (MSN-Fc) and ß-cyclodextrin-poly(N-isopropylacrylamide) (ß-CD-PNIPAM) star-shaped polymer due to the host-guest interactions for controlled drug release. The formation and structure of ß-CD-PNIPAM@MSN-Fc composite nanoparticles was confirmed by FTIR, TGA, TEM and N2 adsorption-desorption isotherms. The size of nanoparticles was about 100-150 nm with well-ordered mesoporous structure and PNIPAM chains coating on the surface as outer shell. The channels of MSNs and hydrophobic cavities of ß-CD were all contributed to the high drug loading capacity for nanoparticles. The release of DOX from nanoparticles was enhanced with the increase of temperature above LCST or adding H2O2 in ambient O2. The release kinetics were studied using different models to explain drug release mechanism. Furthermore, the drug loaded composite nanoparticles exhibited excellent anti-cancer activity.

Multi-Responsive Nanocarriers Based on ß-CD-PNIPAM Star Polymer Coated MSN-SS-Fc Composite Particles.

A temperature, glutathione (GSH), and H2O2 multi-responsive composite nanocarrier (MSN-SS-Fc@ß-CD-PNIPAM) based on ß-cyclodextrin-poly(N-isopropylacrylamide) (ß-CD-PNIPAM) star polymer capped ferrocene modified mesoporous silica nanoparticles (MSN-SS-Fc) was successfully prepared. The surface of the mesoporous silica was first modified by ferrocene (Fc) via a disulfide bond (-SS-) to form an oxidizing and reducing site and then complexed with a ß-CD-PNIPAM star shaped polymer through host-guest interactions as a nano-valve to provide temperature responsive characteristics. The structure and properties of the complex nanoparticles were studied by FTIR, TGA, EDS, Zeta potential, and elemental analysis. Doxorubicin (DOX) and Naproxen (NAP), as model drugs, were loaded into nanocarriers to assess drug loading and release behaviour. The release of drugs from nanocarriers was enhanced with an increase of the GSH, H2O2 concentration, or temperatures of the solution. The kinetics of the release process were studied using different models. This nanocarrier presents successful multi-stimuli responsive drug delivery in optimal stimuli and provides potential applications for clinical treatment.

Stimuli-sensitive hollow spheres from chitosan-graft-ß-cyclodextrin for controlled drug release.

In this paper, sensitive polymeric hollow spheres self-assembled from chitosan-grafted-ß-cyclodextrin (CS-g-CD) and sodium tripolyphosphate (TPP) were prepared for controlled release of doxorubicin (DOX). The assemblies were formed by electrostatic interactions between positively charged amino group in CS-g-CD and negatively charged phosphate in TPP. The hollow spheres with diameters about 100nm were confirmed by transmission electron microscopy (TEM) and laser particle analyzer. The microspheres with hollow cavity were beneficial to improve the drug loading capacity for DOX with entrapment efficiency above 60%. The cumulative release of DOX from CS-g-CD/TPP hollow microspheres increased with the decrease of pH and the increase of temperature or ionic strength. At 37 °C and pH 5.2, the maximum drug release was above 90% with a continuous release rate. In-vitro cytotoxicity tests indicate that drug loaded hollow spheres exhibited evidently inhibition against cancer cells. These sensitive polymeric hollow spheres are expected to be used in biomedical field as potential carrier.

Neuroprotective Effect of Ulinastatin on Spinal Cord Ischemia-Reperfusion Injury in Rabbits.

Ulinastatin (UTI), a trypsin inhibitor, is isolated and purified from human urine and has been shown to exert protective effect on myocardial ischemia reperfusion injury in patients. The present study was aimed at investigating the effect of ulinastatin on neurologic functions after spinal cord ischemia reperfusion injury and the underlying mechanism. The spinal cord IR model was achieved by occluding the aorta just caudal to the left renal artery with a bulldog clamp. The drugs were administered immediately after the clamp was removed. The animals were terminated 48 hours after reperfusion. Neuronal function was evaluated with the Tarlov Scoring System. Spinal cord segments between L2 and L5 were harvested for pathological and biochemical analysis. Ulinastatin administration significantly improved postischemic neurologic function with concomitant reduction of apoptotic cell death. In addition, ulinastatin treatment increased SOD activity and decreased MDA content in the spinal cord tissue. Also, ulinastatin treatment suppressed the protein expressions of Bax and caspase-3 but enhanced Bcl-2 protein expression. These results suggest that ulinastatin significantly attenuates spinal cord ischemia-reperfusion injury and improves postischemic neuronal function and that this protection might be attributable to its antioxidant and antiapoptotic properties.

The effect of safflower yellow on spinal cord ischemia reperfusion injury in rabbits.

Safflower yellow (SY) is the safflower extract and is the one of traditional Chinese medicine. The aim of the present work was to investigate the effect of SY on spinal cord ischemia reperfusion injury (SCIRI) in rabbits. The models of spinal cord ischemia reperfusion (SI/R) were constructed, and the degree of the post-ischemic injury was assessed by means of the neurological deficit scores and plasma levels of lipid peroxidation reactioin and neuronal morphologic changes. SCIRI remarkably affected the functional activities of the hind limbs and activated lipid peroxidation reaction. SY could attenuate apoptosis and SCIRI by enhancing Bcl-2 expression and inhibiting Bax and caspase-3 activation.