Publications by authors named "Guixin Shi"

Ischemic stroke is the primary cause of mortality for individuals with disability worldwide. Tripartite motif 37 (TRIM37) plays multiple regulatory roles in various cellular processes. Our research aimed to investigate the effects of TRIM37 on the progression of ischemic stroke and its related mechanisms.

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Background: Pyroptosis, inflammation-related programed cell death mediated by NLRP3 inflammasome, is involved in the pathogenesis of cerebral hypoxic-ischemic injury. Our study aims to explore the biological role of growth differentiation factor (GDF)15 in oxygen-glucose deprivation/reoxygenation (OGD/R)-induced neuronal pyroptosis.

Methods: HT22 neurons were subjected to OGD/R to simulate cerebral hypoxic-ischemic injury.

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The resolution of SARS-CoV-2 replication hinges on cell-mediated immunity, wherein CD8 T cells play a vital role. Nonetheless, the characterization of the specificity and TCR composition of CD8 T cells targeting non-spike protein of SARS-CoV-2 before and after infection remains incomplete. Here, we analyzed CD8 T cells recognizing six epitopes from the SARS-CoV-2 nucleocapsid (N) protein and found that SARS-CoV-2 infection slightly increased the frequencies of N-recognizing CD8 T cells but significantly enhanced activation-induced proliferation compared to that of the uninfected donors.

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Stroke known as a neurological disease has significant rates of disability and mortality. Middle cerebral artery occlusion (MCAO) models in rodents is crucial in stroke research to mimic human stroke. Building the mRNA and non-conding RNA network is essential for preventing MCAO-induced ischemic stroke occurrence.

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Background: Cytomegalovirus (CMV) infection leads to effector memory CD8 T cell expansion and is associated with immune dysfunction in older adults. However, the molecular alterations of CMV-specific CD8 T cells in CMV infected healthy young and middle-aged adults has not been fully characterized.

Results: We compared CD8 T cells specific for a CMV epitope (pp65, NLV) and an influenza A virus (IAV) epitope (M1, GIL) from the same young and middle-aged healthy adults with serum positive for anti-CMV IgG.

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Perfluorocarbon gas-filled microbubbles are clinically used as ultrasound contrast agents. We have been developing targeted microbubbles based BACS (buoyancy activated cell sorting) or BUBLES (buoyancy enabled separation) for ex vivo cell isolation from bloods for circulating tumor cell (CTC) detection and hematopoietic cell isolation. Recently, we further applied targeted microbubbles for multimarker cell sorting, and as artificial antigen presenting cells (aAPC) for T cell activation and expansion by taking advantage of a number of interesting properties of lipid-shelled microbubbles.

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Backgrounds: Diabetic nephropathy (DN) is one of the most important clinical complications of diabetes mellitus (DM) and is the most common cause of end-stage renal disease. Currently, there is no highly effective medicine that can prevent, halt, or reverse the progressive course of DN. Initial clinical data showed that Tripterygium glycosides (TGs), a traditional Chinese medicine, can decrease proteinuria in patients with DN.

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Stimulation of human primary T cells with immobilized anti-CD3 and anti-CD28 Abs in vitro provide a system to study T cell activation and proliferation and an avenue for expanding T cells for immunotherapy. Magnetic beads conjugated with anti-CD3 and anti-CD28 Abs (Dynabeads Human T-Activator [D-TCA]) have been a golden standard for stimulating human primary T cells in vitro. In this study, we report that an application using anti-CD3 and anti-CD28 Abs conjugated on lipid microbubbles (microbubble-based human T cell activator [MB-TCA]) to stimulate primary human naive T cells resulted in expansion superior to D-TCA.

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Gas-filled microbubbles attached to cell surfaces can interact with focused ultrasound to create microstreaming of nearby fluid. We directly observed the ultrasound/microbubble interaction and documented that under certain conditions fluorescent particles that were attached to the surface of live cells could be removed. Fluorescently labeled liposomes that were larger than 500 nm in diameter were attached to the surface of endothelial cells using cRGD targeting to αvβ3 integrin.

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Circulating tumor cells (CTCs) are extremely rare cells found in blood of metastatic cancer patients. There is a need for inexpensive technologies for fast enrichment of CTCs from large blood volumes. Previous data showed that antibody-conjugated lipid shell immuno-microbubbles (MBs) bind and isolate cells from biological fluids by flotation.

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The construction of engineered bone mostly focuses on simulating the extracellular matrix (ECM) for proper biological activity. However, the complexity of architecture and the variability of the mechanical properties of natural bones are related to individual differences in age, nutritional state, mechanical loading and disease status. Defect substitutions should be normed with the host natural bone, balancing architectural and mechanical adaption, as well as biological activity.

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Vena cava filter (VCF)has been increasingly applied in clinical to efficiently prevent the pulmonary embolism (PE) with the rapid development of VCF. This article summarized the development of VCF, analyzed the relationship between structure and function, described the clinical behaviour of VCF, and final y forecasted the development trend of VCF products.

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Lipid monolayer coated microbubbles are currently being developed to identify vascular regions that express certain surface proteins as part of the new technique of ultrasound molecular imaging. The microbubbles are functionalized with targeting ligands which bind to the desired cells holding the microbubbles in place as the remaining unbound microbubbles are eliminated from circulation. Subsequent scanning with ultrasound can detect the highly reflectant microbubbles that are left behind.

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There is a great interest in targeting and selective ablation of populations of circulating cells for research or therapeutic purposes. Red blood cells (RBCs) are readily available and fully biocompatible long-circulating intravascular carriers (natural life is 120days) that are amenable to chemical modifications, drug loading and reinjection. Here we demonstrate that using our previously described lipophilic ligand painting strategy, red blood cells (RBCs) could be in one step converted into targeted entities that selectively seek and bind various cells in vitro and in vivo.

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With the emerging interest in personalized medicine, there is strong demand for new technologies for clinical sample interrogation. Exfoliated tumor cells in variety of pathological samples (e.g.

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Red blood cells (RBCs) attract significant interest as carriers of biomolecules, drugs, and nanoparticles. In this regard, versatile technologies to attach molecules and ligands to the RBC surface are of great importance. Reported here is a fast and efficient surface painting strategy to attach ligands to the surface of RBCs, and the factors that control the stability and circulation properties of the modified RBCs in vivo.

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Circulating tumor cells (CTCs) are exfoliated at various stages of cancer, and could provide invaluable information for the diagnosis and prognosis of cancers. There is an urgent need for the development of cost-efficient and scalable technologies for rare CTC enrichment from blood. Here we report a novel method for isolation of rare tumor cells from excess of blood cells using gas-filled buoyant immuno-microbubbles (MBs).

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Electrically conducting polypyrrole (PPy) and its composite materials are useful in interfacing electrical components and cells or living tissue. In recent years, significant efforts have been made to bioactivate PPy by incorporating biomolecules. The main objective of this work was to chemically bioactivate PPy particules by incorporating fibronectin (FN) and bovine serum albumin (BSA).

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Electricity has a long history of being used as an alternative clinical treatment and as an effective approach to modifying cellular behaviours in vitro. It has been difficult, however, to take advantage of this modality in tissue generation because of the lack of suitable conductive, biocompatible scaffolding materials. In this study, in order to electrically regulate cell activities, a largely biodegradable conductor made of 5% conductive polypyrrole and 95% biodegradable poly(L-lactide) (PPy/PLLA) was prepared.

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Polypyrrole (PPy) is a promising conductive polymer for tissue engineering and bioelectrical applications. However, its electrical conductivity deteriorates easily in aqueous conditions. Cell adhesion to PPy is also relatively poor.

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Electrically conductive biodegradable polymer membranes were prepared by mixing conductive polypyrrole particles with poly(L-lactic acid) solution followed by solution casting and solvent evaporation. Multi-well electrical cell culture plates were fabricated to host electrically stimulated cell culture and monitor parameters. Human cutaneous fibroblasts were cultured on conductive membranes with or without electrical stimulation (ES).

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Normal and electrically stimulated PC12 cell cultures and the implantation of nerve guidance channels were performed to evaluate newly developed electrically conductive biodegradable polymer composites. Polypyrrole (PPy) doped by butane sulfonic acid showed a significantly higher number of viable cells compared with PPy doped by polystyrenesulfonate after a 6-day culture. The PC12 cells were left to proliferate for 6 days, and the PPy-coated membranes, showing less initial cell adherence, recorded the same proliferation rate as did the noncoated membranes.

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This study evaluated the in vivo biocompatibility and biodegradation behavior of a novel polypyrrole (PPy)/poly(D,L-lactide) (PDLLA) composite and PPy-coated poly(D,L-lactide-co-glycolide) membranes. Test membranes were implanted subcutaneously in rats for 3-120 days. The biocompatibility was assessed by quantifying the alkaline and acid phosphatase secretion, the immunohistochemical staining of the ED-2-positive macrophages, and the histology at the tissue/material interface.

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A novel electrically conductive biodegradable composite material made of polypyrrole (PPy) nanoparticles and poly(d,l-lactide) (PDLLA) was prepared by emulsion polymerization of pyrrole in a PDLLA solution, followed by precipitation. The composite was characterized by scanning electron microscopy and X-ray photoelectron spectroscopy. The electrical stability of the composite containing 5 wt% PPy was investigated in a cell culture environment for 1000 h with 100 mV DC applied voltage.

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The purpose of this study is to investigate the enzymatic degradation behaviors of porous poly(lactide-co-glycolide) (PLGA) foams in the presence of trypsin, in comparison with their hydrolytic degradation. To inspect the effect of trypsin on the degradation of PLGA, both the hydrolytic and enzymatic degradation of non-porous PLGA samples were also performed. The changes of molecular weight and molecular weight distribution (polydispersity) during the degradation were determined by gel permeation chromatograph.

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