Pine Pollen Polysaccharides' and Sulfated Polysaccharides' Effects on UC Mice through Modulation of Cell Tight Junctions and RIPK3-Dependent Necroptosis Pathways.

The purpose of this study is to explore the effects of pine pollen polysaccharides and sulfated polysaccharides on mice with ulcerative colitis and whether they could protect mice from inflammation by regulating the tight junctions of colonic epithelial cells and regulating the RIPK3-dependent necroptosis pathways. Pine pollen polysaccharides were prepared by water boiling and ethanol precipitation. After deproteinedization with trichloroacetic acid, the UV spectrum showed that there were no proteins. One polysaccharide component (PPM60-III) was made by gel filtration chromatography, and then sulfated polysaccharide (SPPM60-III) was derived using the chlorosulfonic acid-pyridine method. After treatment with PPM60-III and SPPM60-III, the body weight of mice with ulcerative colitis induced by dextran sodium sulfate increased, the DAI score decreased, the levels of pro-inflammatory factors and inflammation-related enzymes decreased, and the level of anti-inflammatory factors increased. In addition, after treatment, the expressions levels of tight junction proteins increased, the expressions levels of key proteins of programmed necroptosis decreased, while the level of Caspase-8 increased. The results indicated that pine pollen polysaccharides and sulfated polysaccharides have a certain therapeutic effect on UC mice, and the therapeutic effect may be achieved by regulating the tight junction of colonic epithelial cells and regulating the RIPK3-dependent necroptosis pathways.

Unidirectional cell crawling model guided by extracellular cues.

Cell migration is a highly regulated and complex cellular process to maintain proper homeostasis for various biological processes. Extracellular environment was identified as the main affecting factors determining the direction of cell crawling. It was observed experimentally that the cell prefers migrating to the area with denser or stiffer array of microposts. In this article, an integrated unidirectional cell crawling model was developed to investigate the spatiotemporal dynamics of unidirectional cell migration, which incorporates the dominating intracellular biochemical processes, biomechanical processes and the properties of extracellular micropost arrays. The interpost spacing and the stiffness of microposts are taken into account, respectively, to study the mechanism of unidirectional cell locomotion and the guidance of extracellular influence cues on the direction of unidirectional cell crawling. The model can explain adequately the unidirectional crawling phenomena observed in experiments such as "spatiotaxis" and "durotaxis," which allows us to obtain further insights into cell migration.

Changes of serum Tau, GFAP, TNF-α and malonaldehyde after blast-related traumatic brain injury.

OBJECTIVE: To determine the changes of serum Tau protein, glial fibrillary acidic protein (GFAP), tumor necrosis factor alpha (TNF-α), and malonaldehyde (MDA) in rats after blast-related traumatic brain injury (BTBI) and to provide relative information for further studies on BTBI mechanism and seek specific biomarkers for BTBI. METHODS: Ninety male Sprague-Dawley rats were randomly assigned into three groups: control group, moderate blast injury group, and severe blast injury group (n=30 for each). Rats in the moderate and severe blast injury groups were respectively exposed to corresponding levels of BTBI. After explosion, serum levels of Tau, GFAP, TNF-α, and MDA in each group were determined by Elisa assay at different time points after injury (8 h, 24 h, 3 d, and 6 d). The extent of brain damage was detected by Nissl staining and TUNEL assay. RESULTS: Serum levels of Tau and GFAP rapidly increased and reached the peak at 24 h after either moderate or severe blast injury. All the values were significantly higher than control group at all time points (P<0.05). Serum TNF-α level of both injury groups peaked at 8 h after BTBI and stayed significantly higher than control group at all time points (P<0.05). Serum MDA of two injury groups began to significantly increase at 3 d and the level stayed significantly higher than control group until 6 d (P<0.05). Moreover, unlike the other biomarkers, serum MDA of severe blast injury group was significantly higher than moderate blast injury group at 6 d (P<0.05). CONCLUSION: The changes of serum Tau, GFAP, and TNF-α showed a good sensitivity at the acute phase after BTBI (within 24 h). However, their specificity and correlation with the extent of injury were limited in this experiment. Moreover, although the change of serum MDA showed a poor sensitivity and specificity to the diagnosis of BTBI during the first few days, it can reflect the injury degree at 6 d after injury. Therefore, further studies are needed to improve the methods of detecting more serum markers and investigate the significance of multiple markers in diagnosing BTBI.

Effects of Pine Pollen Polysaccharides and Sulfated Polysaccharides on Ulcerative Colitis and Gut Flora in Mice.

Polysaccharides are important biological macromolecules in all organisms, and have recently been studied as therapeutic agents for ulcerative colitis (UC). However, the effects of Pinus yunnanensis pollen polysaccharides on ulcerative colitis remains unknown. In this study, dextran sodium sulfate (DSS) was used to induce the UC model to investigate the effects of Pinus yunnanensis pollen polysaccharides (PPM60) and sulfated polysaccharides (SPPM60) on UC. We evaluated the improvement of polysaccharides on UC by analyzing the levels of intestinal cytokines, serum metabolites and metabolic pathways, intestinal flora species diversity, and beneficial and harmful bacteria. The results show that purified PPM60 and its sulfated form SPPM60 effectively alleviated the disease progression of weight loss, colon shortening and intestinal injury in UC mice. On the intestinal immunity level, PPM60 and SPPM60 increased the levels of anti-inflammatory cytokines (IL-2, IL-10, and IL-13) and decreased the levels of proinflammatory cytokines (IL-1ß, IL-6, and TNF-α). On the serum metabolism level, PPM60 and SPPM60 mainly regulated the abnormal serum metabolism of UC mice by regulating the energy-related and lipid-related metabolism pathways, respectively. On the intestinal flora level, PPM60 and SPPM60 reduced the abundance of harmful bacteria (such as Akkermansia and Aerococcus) and induced the abundance of beneficial bacteria (such as lactobacillus). In summary, this study is the first to evaluate the effects of PPM60 and SPPM60 on UC from the joint perspectives of intestinal immunity, serum metabolomics, and intestinal flora, which may provide an experimental basis for plant polysaccharides as an adjuvant clinical treatment of UC.

Temperature and Pressure Effects on Unrecoverable Voids in Li Metal Solid-State Batteries.

All-solid-state batteries (ASSB) can potentially achieve high gravimetric and volumetric energy densities (900 Wh/L) if paired with a lithium metal anode and solid electrolyte. However, there is a lack in critical understanding about how to operate lithium metal cells at high capacities and minimize unwanted degradation mechanisms such as dendrites and voids. Herein, we investigate how pressure and temperature influence the formation and annihilation of unrecoverable voids in lithium metal upon stripping. Stack pressure and temperature are effective means to initiate creep-induced void filling and decrease charge transfer resistances. Applying stack pressure enables lithium to deform and creep below the yield stress during stripping at high current densities. Lithium creep is not sufficient to prevent cell shorting during plating. Three-electrode experiments were employed to probe the kinetic and morphological limitations that occur at the anode-solid electrolyte during high-capacity stripping (5 mAh/cm2). The role of cathode-LLZO interface, which dictates cyclability and capacity retention in full cells, was also studied. This work elucidates the important role that temperature (external or in situ generated) has on reversible operation of solid-state batteries.

Privacy Law Protection Based on the Information Security Assurance Algorithm.

With the continuous development of network technology, the production and lifestyle of human beings are also quietly changing. People find that the network makes life faster and more convenient and also makes our life more "transparent." The openness, sharing, and convenience of the network make it easier to infringe on the privacy rights of others, bringing an unprecedented impact on traditional privacy protection. This paper studied information security assurance-related algorithms and built an information security assurance model. Through this model, some privacy violation events existing in the network today were analyzed. Then, a corresponding questionnaire was constructed according to some of the problems of these events. The questionnaire is mainly used for research on people of all age groups, mainly to study their understanding of relevant legal knowledge and their views on the law. A total of 188 valid questionnaires were collected in this survey. Only 37.23% people knew a lot about the law. Most of them learned it from the Internet, and they rarely learned about it from relevant books. About 70% people believe that the law plays a big role in privacy protection, and they will choose legal help if they encounter privacy violations. However, this is inconsistent with some data obtained from the information security assurance model. Through analysis, it can be seen that although they want legal help, they lack the relevant knowledge of the law, and they do not know whether the privacy of individuals has been violated. Therefore, it is necessary to strengthen personal knowledge of privacy protection laws and improve the personal information legal protection and fair use system.

Determining Dynamic Mechanical Properties for Elastic Concrete Material Based on the Inversion of Spherical Wave.

The paper presents a new method to study the dynamic mechanical properties of concrete under low pressure and a high strain rate via the inversion of spherical wave propagation. The dynamic parameters of rate-dependent constitutive relation of elastic concrete are determined by measured velocity histories of spherical waves. Firstly, the particle velocity time history profiles in the low stress elastic region at the radii of 100.6 mm, 120.6 mm, 140.6 mm, 160 mm, and 180.6 mm are measured in the semi-infinite space of concrete by using the mini-explosive ball and electromagnetic velocity measurement technology. Then, based on the universal spherical wave conservation equation and the fact that the accommodation relationship in state equation satisfies linear elastic law, the inverse problem analysis of spherical waves in concrete (called "NV + T0/SW") is proposed, which can obtain the dynamic numerical constitutive behavior of concrete in three-dimensional stress by measuring the velocity histories. The numerical constitutive relation is expressed in the form of distortion, and it is found that the distortion law has an obvious rate effect. Finally, the rate-dependent dynamic parameters in concrete are determined by the standard linear solid model. The results show that the strain rate effect of concrete cannot be ignored with the strain rate range of 102 1/s. This study can provide a feasible method to determine the dynamic parameters of rate-dependent constitutive relation of concretes. This method has good applicability, especially in the study of the dynamic behavior of multicomponent composite materials with large-size particle filler.

Review of cellular mechanotransduction on micropost substrates.

As physical entities, living cells can sense and respond to various stimulations within and outside the body through cellular mechanotransduction. Any deviation in cellular mechanotransduction will not only undermine the orchestrated regulation of mechanical responses, but also lead to the breakdown of their physiological function. Therefore, a quantitative study of cellular mechanotransduction needs to be conducted both in experiments and in computational simulations to investigate the underlying mechanisms of cellular mechanotransduction. In this review, we present an overview of the current knowledge and significant progress in cellular mechanotransduction via micropost substrates. In the aspect of experimental studies, we summarize significant experimental progress and place an emphasis on the coupled relationship among cellular spreading, focal adhesion and contractility as well as the influence of substrate properties on force-involved cellular behaviors. In the other aspect of computational investigations, we outline a coupled framework including the biochemically motivated stress fiber model and thermodynamically motivated adhesion model and present their predicted biomechanical responses and then compare predicted simulation results with experimental observations to further explore the mechanisms of cellular mechanotransduction. At last, we discuss the future perspectives both in experimental technologies and in computational models, as well as facing challenges in the area of cellular mechanotransduction.

A novel rat model of blast-induced traumatic brain injury simulating different damage degree: implications for morphological, neurological, and biomarker changes.

In current military conflicts and civilian terrorism, blast-induced traumatic brain injury (bTBI) is the primary cause of neurotrauma. However, the effects and mechanisms of bTBI are poorly understood. Although previous researchers have made significant contributions to establishing animal models for the simulation of bTBI, the precision and controllability of blast-induced injury in animal models must be improved. Therefore, we established a novel rat model to simulate blast-wave injury to the brain. To simulate different extents of bTBI injury, the animals were divided into moderate and severe injury groups. The miniature spherical explosives (pentaerythritol tetranitrate) used in each group were of different sizes (2.5 mm diameter in the moderate injury group and 3.0 mm diameter in the severe injury group). A specially designed apparatus was able to precisely adjust the positions of the miniature explosives and create eight rats with bTBI simultaneously, using a single electric detonator. Neurological functions, gross pathologies, histopathological changes and the expression levels of various biomarkers were examined after the explosion. Compared with the moderate injury group, there were significantly more neurological dysfunctions, cortical contusions, intraparenchymal hemorrhages, cortical expression of S-100ß, myelin basic protein, neuron-specific enolase, IL-8, IL-10, inducible nitric oxide synthase, and HIF-1α in the severe injury group. These results demonstrate that we have created a reliable and reproducible bTBI model in rats. This model will be helpful for studying the mechanisms of bTBI and developing strategies for clinical bTBI treatment.