Ratiometric Fluorescence Probes for In Situ Imaging of Membrane Tension in Live Cells.

Membrane tension is an important physical parameter of describing cellular homeostasis, and it is widely used in the study of cellular processes involving membrane deformation and reorganization, such as cell migration, cell spreading, and cell division. Despite the importance of membrane tension, direct measurement remains difficult. In this work, we developed a ratiometric fluorescent probe sensitive to membrane tension by adjusting the carbon chain structure based on polarity-sensitive fluorophores.

In Situ Quantitative Imaging of Plasma Membrane Stiffness in Live Cells Using a Genetically Encoded FRET Sensor.

Cell membrane stiffness is critical for cellular function, with cholesterol and sphingomyelin as pivot contributors. Current methods for measuring membrane stiffness are often invasive, ex situ, and slow in process, prompting the need for innovative techniques. Here, we present a fluorescence resonance energy transfer (FRET)-based protein sensor designed to address these challenges.

Electrochemiluminescence-Based Single-Particle Tracking of the Biomolecules Moving along Intercellular Membrane Nanotubes between Live Cells.

Electrochemiluminescence (ECL) imaging, a rapidly evolving technology, has attracted significant attention in the field of cellular imaging. However, its primary limitation lies in its inability to analyze the motion behaviors of individual particles in live cellular environments. In this study, we leveraged the exceptional ECL properties of quantum dots (QDs) and the excellent electrochemical properties of carbon dots (CDs) to develop a high-brightness ECL nanoprobe (CDs-QDs) for real-time ECL imaging between living cells.

Accurate Cancer Screening and Prediction of PD-L1-Guided Immunotherapy Efficacy Using Quantum Dot Nanosphere Self-Assembly and Machine Learning.

Accurate quantification of exosomal PD-L1 protein in tumors is closely linked to the response to immunotherapy, but robust methods to achieve high-precision quantitative detection of PD-L1 expression on the surface of circulating exosomes are still lacking. In this work, we developed a signal amplification approach based on aptamer recognition and DNA scaffold hybridization-triggered assembly of quantum dot nanospheres, which enables bicolor phenotyping of exosomes to accurately screen for cancers and predict PD-L1-guided immunotherapeutic effects through machine learning. Through DNA-mediated assembly, we utilized two aptamers for simultaneous ultrasensitive detection of exosomal antigens, which have synergistic roles in tumor diagnosis and treatment prediction, and thus, we achieved better sample classification and prediction through machine-learning algorithms.

[Neuroprotective effect and mechanism of cPLA2 inhibitor increases autophagic flux on spinal cord injury].

Objective: To investigate the mechanism of cytosolic phospholipase A2(cPLA2) inhibitor to improve neurological function after spinal cord injury (SCI).

Methods: Thirty-six 3 months old female SD rats, with body mass (280±20) g, were divided into three groups (=12):sham group, SCI group, and SCI+ arachidonyl trifluoromethyl ketone(AACOCF3) group. Balloon compression SCI model was established in all three groups.

Engineered Lipidic Nanomaterials Inspired by Sphingomyelin Metabolism for Cancer Therapy.

Sphingomyelin (SM) and its metabolites are crucial regulators of tumor cell growth, differentiation, senescence, and programmed cell death. With the rise in lipid-based nanomaterials, engineered lipidic nanomaterials inspired by SM metabolism, corresponding lipid targeting, and signaling activation have made fascinating advances in cancer therapeutic processes. In this review, we first described the specific pathways of SM metabolism and the roles of their associated bioactive molecules in mediating cell survival or death.

Artificial Cells for Cellular Behavior Mimicry Induced by Sphingomyelin Degradation.

Sphingomyelinase (SMase), a hydrolase of sphingomyelin (SM) enriched in the outer leaflet of the plasma membrane of mammalian cells, is closely associated with the onset and development of many diseases, but the specific mechanisms of SMase on the cell structure, function, and behavior are not yet fully understood due to the complexity of the cell structure. Artificial cells are minimal biological systems constructed from various molecular components designed to mimic cellular processes, behaviors, and structures, which are excellent models for studying biochemical reactions and dynamic changes in cell membranes. In this work, we presented an artificial cell model that mimics the lipid composition and content of the outer leaflet of mammalian plasma membranes for studying the effect of SMase on cell behavior.

ADP-Ribosylation Factor Like GTPase 4C (ARL4C) augments stem-like traits of glioblastoma cells by upregulating ALDH1A3.

Glioma cells with stem cell-like properties are crucial for tumor initiation, progression and therapeutic resistance. Therefore, identifying specific factors in regulating stem-like traits is critical for the design of novel glioma therapeutics. Herein, we reported that ADP-Ribosylation Factor Like GTPase 4C (ARL4C) was highly expressed in glioma stem-like cells (GSLCs).

[Research of autophagy activity between rat bone marrow mesenchymal stem neural differentiation].

Objective: To study the autophagy activity between rat bone marrow stem cells (BMSCs) neural differentiation in order to explore the mechanism involve in this process.

Methods: BMSCs were passed by 3 generation, then was induced with the revulsant 2% (DMSO) + 200 µmol/L (BHA), NSE expression was detected by immunocytochemical stain, the mRNA expression of autophagy associated genes L3B, Beclinl, Atg5, Atg7, Atg10 were detected by RT-PCR, the autophagy protein LC3B was examined by Western blot and flow cytometry analysis.

Results: BMSCs were passed by 3 generation, the purity of BMSCs could reach more than 90%, the morphology of cells were like fibroblasts, after the revulsant 2% DMSO + 200 µmol/L BRA induced, cells were extended long neurites, like nerve cells, positive rate of NSE staining was (83±5) %, RT-PCR results showed that the expression of autophagy associated genes LC3B, Beclinl, Atg5, Atg7 Atg0 were rised after BMSCs neural differentiation, Western blot analysis showed that the LC3B-II protein expression was increased after neural differentiation and the MFI of L3B was highten by flow cytometry.

[Measurement of Foxp3 and NFAT1 in children with aplastic anemia].

Objective: To study the expression of Foxp3 and NFAT1 protein in peripheral blood (PB) in children with aplastic anemia (AA) and their roles in the pathogenesis of AA.

Methods: The expression levels of Foxp3 and NFAT1 protein of mononuclear cells in PB were measured by Western blot in 68 children with AA before and after treatment and in 60 normal children (control group). The correlation between Foxp3 and NFAT1 protein expression and the correlation of the Foxp3 and NFAT1 protein expression with blood Hb, WBC and platelet levels were analyzed.

[Construction of inducible lentiviral vector containing human Notch1 and EGFP gene and its expression in PC12 cells].

Objective: To construct inducible lentiviral vector containing human Notch1 intracellular domain (NICD) gene and enhanced green fluorescent protein (EGFP), and to study its expression in PC12 cells.

Methods: NICD cDNA was amplified by RT-PCR from human placenta tissue. EGFP gene was amplified by PCR from pEGFP-C1.

[Study on the correlation of the levels of serum IFN-γ and RANTES and rabbit vulnerable atherosclerotic plaque].

Aim: To investigate the correlation between the levels of serum IFN-γ and RANTES (regulated upon on activation on normal T cell expressed and secreted) and rabbit atherosclerotic plaque stability.

Methods: 30 male New Zealand rabbits were randomly divided into three groups: control group, stable atherosclerotic plaque group(AS group) and vulnerable atherosclerotic plaque group(VAP group), with 10 rabbits in a group. The control group was given normal diet while the AS group and the VAP group were given high-fat diet for 12 weeks.

[Abeta(25-35) and ginsenoside Rb1 influence on the expression of GSK-3beta, CDK-5 and PP2A in differentiated neural stem cells of rats].

Objective: To explore the expression of GSK-3beta, CDK-5 and PP2A and the regulation of them by Abeta(25-35) and ginsenoside Rb1 after neural stem cells (NSCs) are transformed into neurons.

Methods: To culture NSCs from the dentate gyrus of newborn rats(24 h) hippocampus in vitro. NSCs of the third passage were induced towards neurons; the expressions of GSK-3beta(pTyr279,216), PP2A and the regulation of them by Abeta(25-35) and ginsenoside Rb1 were tested by the immunofluorescence cytochemical staining after NSCs had been induced for one week; The expressions of GSK-3beta, CDK-5, PP2A and the regulation of them by Abeta(25-35) and ginsenoside Rb1 were detected with RT-PCR.

[Nifedipine regulated expression of bcl-2 in human gingival epithelial cells in vitro].

Purpose: To investigate the effect of nifedipine(NIF) on transcription of bcl-2 in human gingival epithelial cells(HGECs) in vitro and to study the pathogenesis of epithelial thickening in drug-induced gingival overgrowth(DGO).

Methods: The gingival tissues obtained from periodontal surgeries were digested with enzyme and HGECs were cultured in vitro; HGECs were identified by immunohistochemistry; bcl-2 mRNA levels were quantitated by Real-time PCR 24 hours and 48 hours after cells stimulated by NIF with different concentration (0microg/ml, 1microg/ml,2microg/ml,3microg/ml), in which 0microg/ml NIF as blank control. The data was analyzed by one-way ANOVA using SPSS 11.

[Development of a universal primers PCR-coupled liquid bead array to detect biothreat bacteria].

Objective: To develop a fast, high-throughput screening method with suspension array technique for simultaneous detection of biothreat bacteria.

Methods: 16 S rDNA universal primers for Bacillus anthracis, Francisella tularensis, Yersinia pestis, Brucella spp.and Burkholderia pseudomallei were selected to amplify corresponding regions and the genus-specific or species-specific probes were designed.

[Amelogenin expression in cultured human dental pulp and periodontium related cells].

Purpose: To investigate gene expression of amelogenin (Am) in human gingival epithelial cells(HGEC) and also other oral ectomesenchyme cells (human gingival fibroblasts, human periodontal ligament fibroblasts and human pulp cells).

Methods: The amelogenin mRNA expression patterns were determined by the reverse transcription polymerase chain reaction (RT-PCR),and the protein expression was studied with Western blotting.

Results: There was no amelogenin expression detected in any of the cells.

[Development of a multiplex PCR-suspension array for simultaneous detection of five bioterrorism bacteria].

Objective: To develop a rapid, high-throughput screening method of gene suspension array technique to simultaneously detect five bioterrorism bacteria: Bacillus anthracis, Francisella tularensis, Yersinia pestis, Brucella spp. and Burkholderia pseudomallei.

Methods: Highly validated specific primers were used to amplify diagnostic regions unique to each pathogen.

[The change of potassium current of neural stem cells cultured in vitro from newborn rat hippocampus].

Aim: To observe the change of potassium current on cultured neurons differentiated from hippocampus neural stem cells of the newborn rat.

Methods: Neural stem cells from newborn rat hippocampus were cultured in vitro and passaged continuously. Differentiation of the cell was induced by serum and removing mitogens.

[Expression changes of Notch-related genes during the differentiation of human mesenchymal stem cells into neurons].

The Notch signaling pathway has been implicated in the regulation of cell-fate decisions such as differentiation of embryo stem cells and neural stem cells into neurons. We cultured human mesenchymal stem cells (hMSCs) in vitro and induced hMSCs to differentiate into neural cells by beta-mercaptoethanol (beta-ME), DMSO and 3-tert-butyl-4-hydroxyanisole (BHA). Immunocytochemistry was utilized to detect neuron-specific enolase (NSE) and Nissl body, and flow cytometry was used to determine cell growth phases.

[Human bone marrow mesenchymal stem cells differentiated into dopaminergenic neurons in vitro].

Midbrain dopamine (DA) neurons play an essential role in modulating motor control. Defects in central DA neurons affect a wide range of neurological disorders including Parkinson's disease (PD). The greatest motivation in the field has been the potential use of DA neurons for cell transplantation therapy in Parkinsonian patients.

[Expressions of Tau protein during the differentiation process of mesenchymal stem cells into neural cells].

Aim: To observe expressions and changes of Tau protein, pSer202 and Tau protein's contents during the differentiation process of bone-marrow mesenchymal stem cells (MSCs) into neural cells, and discuss Tau's effects on it.

Methods: EGF and bFGF were combined for the induction of 4th, 8th, and 12th-MSCs into neural cells. Expressions of Tau protein and pSer202 were tested by immunocytochemistry.

[Effects of fenofibrate on the proliferation and apoptosis and nitric oxide synthase expression of cultured human umbilical vein endothelial cells induced by lysophosphatidylcholine].

Objective: To investigate the effects of fenofibrate on the proliferation and apoptosis and endothelial nitric oxide synthase (eNOS) mRNA expression of cultured human umbilical vein endothelial cells (HUVECs) induced by lysophosphatidylcholine (LPC).

Methods: HUVECs were cultured in vitro. The study was designated to 5 groups according to fenofibrate concentration: control group, LPC group, LPC + low-concentration fenofibrate (10 micromol/L), LPC + middle-concentration fenofibrate (50 micromol/L), and LPC + high-concentration fenofibrate (100 micromol/L).

Effects of EGF and bFGF on expression of microtubule-associated protein tau and MAP-2 mRNA in human umbilical cord mononuclear cells.

The aim of this study was to explore the regulatory effects of cytokines, such as EGF and bFGF, on expression of the neural-specific molecules tau and MAP2 mRNA in mononuclear cells (MNCs) derived from human umbilical cord blood (UCB). Phenotypic changes were monitored by inverse phase-contrast microscopy. Tau and MAP2 mRNA were determined by reverse-transcriptase polymerase chain reaction (RT-PCR).