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1.
J Colloid Interface Sci ; 652(Pt B): 2042-2053, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37696058

ABSTRACT

The all-solid-state sodium battery has emerged as a promising candidate for energy storage. However, the limited electrochemical stability of the solid electrolyte, particularly in the presence of Na metal at the anode, along with low ionic conductivity, hinders its widespread application. In this work, the design of P and O elements in Na3SbS4 solid electrolyte was investigated through a series of structural tests and characterizations. The electrochemical stability was remarkably improved in the Na/Na3SbP0.16S3.6O0.4/Na battery, exhibiting a stability of 260 h under a current of 0.1 mA cm-2. Additionally, the room temperature conductivity of Na3SbP0.16S3.6O0.4 was enhanced to 3.82 mS cm-1, maintaining a value comparable to commercial standards. The proposed design strategy provides an approach for developing sodium ion solid-state batteries with high energy density and long lifespan. The stability of the solid electrolyte interface at the Na | solid electrolyte interface proves critical for the successful assembly of all-solid-state sodium ion batteries.

2.
Dalton Trans ; 52(23): 7893-7905, 2023 Jun 13.
Article in English | MEDLINE | ID: mdl-37218294

ABSTRACT

The fabrication of all electrolytes from noncombustible ceramic materials offers a superior option for providing safer and higher-capacity batteries to fulfill future energy needs. To achieve a competitive performance with combustible liquid electrolytes used in commercial Li-ion batteries, the creation of ceramic material compositions with a high electrical conductivity is necessary. Here, we report that co-doping with W and halogens results in a superconductivity of 13.78 mS cm-1 in a cubic-phase Na3SbS4 glass ceramic electrolyte. After undergoing high-temperature heat treatments, the W ions in the electrolyte can facilitate the replacement of S atoms with halogens, introducing many Na vacancies. The samples also had a high degree of cycling stability. An excellent glass ceramic electrolyte for Na ion batteries will be constructed for Na3SbW0.25Cl0.25S4.

3.
Opt Express ; 31(4): 5843-5852, 2023 Feb 13.
Article in English | MEDLINE | ID: mdl-36823856

ABSTRACT

Direct femtosecond laser writing of ferroelectric domain structures has been an indispensable technique for engineering the second-order optical nonlinearity of materials in three dimensions. It utilizes localized thermoelectric field motivated by nonlinear absorption at the position of laser focus to manipulate domains. However, the impact of laser wavelengths, which is pivotal in nonlinear absorption, on the inverted domains is still sketchy. Herein, the light-induced ferroelectric domain inversion is experimentally studied. It is shown that the domain inversions can be achieved over a broad spectral range, but the optical threshold for domain inversion varies dramatically with the laser wavelength, which can be explained by considering the physical mechanism of femtosecond laser poling and nonlinear absorption properties of the crystal. Meanwhile, the effects of other laser processing parameters are also experimentally investigated. Our findings are useful to guide the fabrication of high-performance optical and electronic devices based on ferroelectric domains.

4.
J Clin Lab Anal ; 36(10): e24685, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36045604

ABSTRACT

BACKGROUND: Vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) modulate atherosclerosis by promoting leukocyte infiltration, neutrophil recruitment, endothelial cell proliferation, etc., which may directly or indirectly facilitate the occurrence of major adverse cardiac events (MACE). This study intended to investigate the value of VCAM-1 and ICAM-1 for predicting MACE in ST-segment elevation myocardial infarction (STEMI) patients. METHODS: Totally, 373 STEMI patients receiving the percutaneous coronary intervention and 50 health controls (HCs) were included. Serum VCAM-1 and ICAM-1 were detected by ELISA. Meanwhile, MACE was recorded during a median follow-up of 18 (range: 1-46) months in STEMI patients. RESULTS: Vascular cell adhesion molecule-1 and ICAM-1 were raised in STEMI patients compared with HCs (both p < 0.001). VCAM-1 (p = 0.002) and ICAM-1 (p = 0.012) high were linked with raised accumulating MACE rate in STEMI patients. Notably, VCAM-1 high (hazard ratio [HR] = 2.339, p = 0.031), age ≥ 65 years (HR = 2.019, p = 0.039), history of diabetes mellitus (DM) (HR = 2.395, p = 0.011), C-reactive protein (CRP) ≥ 5 mg/L (HR = 2.550, p = 0.012), multivessel disease (HR = 2.561, p = 0.007) independently predicted MACE risk in STEMI patients. Furthermore, a nomogram-based prediction model combining these factors was established, exhibiting an acceptable value for estimating 1, 2, and 3-year MACE risk, with AUC of 0.764, 0.716, and 0.778, respectively, in STEMI patients. CONCLUSION: This study confirms the value of VCAM-1 and ICAM-1 measurement in predicting MACE risk in STEMI patients. Moreover, VCAM-1 plus other traditional prognostic factors (such as age, history of DM, CRP, and multivessel disease) cloud further improve the predictive accuracy of MACE risk in STEMI patients.


Subject(s)
Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction , Aged , C-Reactive Protein/analysis , Humans , Intercellular Adhesion Molecule-1 , Percutaneous Coronary Intervention/adverse effects , Predictive Value of Tests , Risk Factors , Vascular Cell Adhesion Molecule-1
5.
Brief Bioinform ; 23(3)2022 05 13.
Article in English | MEDLINE | ID: mdl-35368077

ABSTRACT

Survival analysis is a technique for identifying prognostic biomarkers and genetic vulnerabilities in cancer studies. Large-scale consortium-based projects have profiled >11 000 adult and >4000 pediatric tumor cases with clinical outcomes and multiomics approaches. This provides a resource for investigating molecular-level cancer etiologies using clinical correlations. Although cancers often arise from multiple genetic vulnerabilities and have deregulated gene sets (GSs), existing survival analysis protocols can report only on individual genes. Additionally, there is no systematic method to connect clinical outcomes with experimental (cell line) data. To address these gaps, we developed cSurvival (https://tau.cmmt.ubc.ca/cSurvival). cSurvival provides a user-adjustable analytical pipeline with a curated, integrated database and offers three main advances: (i) joint analysis with two genomic predictors to identify interacting biomarkers, including new algorithms to identify optimal cutoffs for two continuous predictors; (ii) survival analysis not only at the gene, but also the GS level; and (iii) integration of clinical and experimental cell line studies to generate synergistic biological insights. To demonstrate these advances, we report three case studies. We confirmed findings of autophagy-dependent survival in colorectal cancers and of synergistic negative effects between high expression of SLC7A11 and SLC2A1 on outcomes in several cancers. We further used cSurvival to identify high expression of the Nrf2-antioxidant response element pathway as a main indicator for lung cancer prognosis and for cellular resistance to oxidative stress-inducing drugs. Altogether, these analyses demonstrate cSurvival's ability to support biomarker prognosis and interaction analysis via gene- and GS-level approaches and to integrate clinical and experimental biomedical studies.


Subject(s)
Biomarkers, Tumor , Lung Neoplasms , Adult , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Cell Line , Child , Gene Expression Regulation, Neoplastic , Humans , Lung Neoplasms/genetics , Survival Analysis
6.
Front Surg ; 9: 839157, 2022.
Article in English | MEDLINE | ID: mdl-35223980

ABSTRACT

OBJECTIVE: To explore the influence of CYP2C19 gene combined with platelet function test on clinical prognosis of patients with complex coronary artery disease receiving antiplatelet therapy after PCI. METHODS: A total of 200 patients undergoing PCI in our hospital due to complex coronary artery disease from February 2019 to February 2021 were selected and divided into the control group and the observation group according to whether CYP2C19 gene detection was performed. The control group was treated with dual antiplatelet therapy of classical aspirin combined with clopidogrel, and the observation group was treated with individual antiplatelet therapy. The patients in the two groups were followed up for 1 year after PCI, and their quality of life was assessed using the Seattle Angina Questionnaire (SAQ score). The occurrence of major adverse cardiovascular events (MACE) during the follow-up period was also recorded. RESULTS: The incidence of total MACE events in the observation group was slightly less than that in the control group, and the difference was statistically significant (P = 0.040). In particular, the observation group was superior to the control group in reducing the readmission rate of recurrent unstable angina pectoris, and the difference was statistically significant (P = 0.023). The location of coronary culprit lesions with recurrent ischemic events was commonly seen in non-interventional target lesions (interventional/non-interventional target sites: 12.9%: 77.1%). The SAQ score in the observation group was larger than that in the control group, and the difference was statistically significant (P = 0.012). There was no statistical difference in the incidence of major bleeding between the two groups (P = 0.352). CONCLUSION: Using CYP2C19 genotype combined with platelet function test to guide individualized antiplatelet therapy after complex coronary artery PCI is beneficial to reducing ischemic events in a short period (1 year), mainly due to reducing the risk of readmission for recurrent unstable angina pectoris, and improving the quality of daily life of patients without increasing the risk of massive hemorrhage, which can improve clinical prognosis.

7.
Nucleic Acids Res ; 49(W1): W207-W215, 2021 07 02.
Article in English | MEDLINE | ID: mdl-34019643

ABSTRACT

Transcriptome profiling is essential for gene regulation studies in development and disease. Current web-based tools enable functional characterization of transcriptome data, but most are restricted to applying gene-list-based methods to single datasets, inefficient in leveraging up-to-date and species-specific information, and limited in their visualization options. Additionally, there is no systematic way to explore data stored in the largest transcriptome repository, NCBI GEO. To fill these gaps, we have developed eVITTA (easy Visualization and Inference Toolbox for Transcriptome Analysis; https://tau.cmmt.ubc.ca/eVITTA/). eVITTA provides modules for analysis and exploration of studies published in NCBI GEO (easyGEO), detailed molecular- and systems-level functional profiling (easyGSEA), and customizable comparisons among experimental groups (easyVizR). We tested eVITTA on transcriptomes of SARS-CoV-2 infected human nasopharyngeal swab samples, and identified a downregulation of olfactory signal transducers, in line with the clinical presentation of anosmia in COVID-19 patients. We also analyzed transcriptomes of Caenorhabditis elegans worms with disrupted S-adenosylmethionine metabolism, confirming activation of innate immune responses and feedback induction of one-carbon cycle genes. Collectively, eVITTA streamlines complex computational workflows into an accessible interface, thus filling the gap of an end-to-end platform capable of capturing both broad and granular changes in human and model organism transcriptomes.


Subject(s)
Data Visualization , Databases, Genetic , Gene Expression Profiling/methods , Internet , Transcriptome/genetics , Animals , COVID-19/genetics , COVID-19/virology , Caenorhabditis elegans/genetics , Caenorhabditis elegans/metabolism , Humans , Immunity, Innate , Nasopharynx/virology , S-Adenosylmethionine/metabolism , SARS-CoV-2/genetics , SARS-CoV-2/pathogenicity , Species Specificity , Workflow
8.
Opt Express ; 29(3): 4048-4057, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-33770992

ABSTRACT

We demonstrate a watt-level mid-infrared supercontinuum source, with the spectrum covering the infrared region from 2 to 6.5 µm, in an all-fiber structured laser transmission system. To further improve the SC spectral bandwidth, power and system compactness in the follow-up As2S3 fiber, we theoretically and experimentally explored some knotty problems that would potentially result in the As2S3 fiber end-facet failure and low SC output power during the high-power butt-coupling process and proposed an optimal coupling distance on the premise of the safety of As2S3 fiber end face. In addition, we also built a multi-pulse pumping model for the first time to more precisely estimate the SC spectral evolution in As2S3 fiber. This work will give an important reference to someone who is working on the all-fiber structured, high-power mid- and far-infrared supercontinuum source.

9.
Sci Bull (Beijing) ; 65(8): 651-657, 2020 Apr 30.
Article in English | MEDLINE | ID: mdl-36659134

ABSTRACT

The direct hydrogenation of CO2 using H2 gas is a one-stone-two-birds route to produce highly value-added hydrocarbon compounds and to lower the CO2 level in the atmosphere. However, the transformation of CO2 and H2 into hydrocarbons has always been a great challenge while ensuring both the activity and selectivity over abundant-element-based nanocatalysts. In this work, we designed a Schottky heterojunction composed of electron-rich MoC nanoparticles embedded inside an optimized nitrogen-doped carbon support (MoC@NC) as the first example of noble-metal-free heterogeneous catalysts to boost the activity of and specific selectivity for CO2 hydrogenation to formic acid (FA) in liquid phase under mild conditions (2 MPa pressure and 70 °C). The MoC@NC catalyst with a high turnover frequency (TOF) of 8.20 molFA molMoC-1 h-1 at 140 °C and an excellent reusability are more favorable for real applications.

10.
Mol Genet Genomic Med ; 7(9): e909, 2019 09.
Article in English | MEDLINE | ID: mdl-31368668

ABSTRACT

BACKGROUND: Patients of coronary artery disease (CAD) with type 2 diabetes mellitus (DM2) show increased mortality risk than CAD patients without DM2, while few biomarkers can be used to discriminate them. METHODS: Fifty-nine patients of CAD with DM2 (DM2-CAD group), 79 patients of CAD without DM2 (CAD group), and 63 healthy control subjects were recruited. Circulating miR-130 (miR-130a and miR-130b) and PPAR-γ (peroxisome proliferator-activated receptor gamma) were measured and their Pearson correlation was analyzed. 3' UTR binding prediction and luciferase assay were used to determine the target relationship between miR-130 and PPAR-γ. Receiver operating characteristics (ROC) analysis was performed to test the discrimination ability of miR-130 between DM2-CAD and CAD groups. RESULTS: miR-130a and miR-130b showed decreased expression in DM2-CAD group when compared with the CAD group and health control. Both bioinformatics and luciferase assays showed that miR-130 could bind the 3' UTR of PPAR-γ. Furthermore, miR-130 negatively correlated with PPAR-γ in both CAD and DM2-CAD group in Pearson's coefficient analysis. Both miR-130a and miR-130b were able to discriminate DM2-CAD group from CAD group and control subjects. CONCLUSION: Circulating miR-130 may regulate the expression of PPAR-γ and can be used as a biomarker to discriminate DM2-CAD from CAD.


Subject(s)
Cell-Free Nucleic Acids/blood , Coronary Artery Disease/blood , Diabetes Complications/blood , Diabetes Mellitus, Type 2/blood , MicroRNAs/blood , PPAR gamma/biosynthesis , Aged , Biomarkers/blood , Female , Gene Expression Regulation , Humans , Male , Middle Aged
11.
J Am Chem Soc ; 141(1): 38-41, 2019 Jan 09.
Article in English | MEDLINE | ID: mdl-30525578

ABSTRACT

Highly efficient fixation of CO2 for the synthesis of useful organic carbonates has drawn much attention. The design of sustainable Lewis acid-base pairs, which has mainly relied on expensive organic ligands, is the key challenge in the activation of the substrate and CO2 molecule. Here, we report the application of Mott-Schottky type nanohybrids composed of electron-deficient Cu and electron-rich N-doped carbon for CO2 fixation. A ligand-free and additive-free method was used to boost the basicity of the carbon supports and the acidity of Cu by increasing the Schottky barrier at their boundary, mimicking the beneficial function of organic ligands acting as the Lewis acid and base in metal-organic frameworks (MOFs) or polymers and simultaneously avoiding the possible deactivation associated with the necessary stability of a heterogeneous catalyst. The optimal Cu/NC-0.5 catalyst exhibited a remarkably high turnover frequency (TOF) value of 615 h-1 at 80 °C, which is 10 times higher than that of the state-of-the-art metal-based heterogeneous catalysts in the literature.

12.
Med Sci Monit ; 24: 9376-9384, 2018 Dec 24.
Article in English | MEDLINE | ID: mdl-30581189

ABSTRACT

BACKGROUND Vitamin D (VD) deficiency and local inflammation of plaque are potential new risk factors and prevention goals for coronary heart disease (CHD). MATERIAL AND METHODS This study included 135 CHD patients and 45 chest tightness or chest pain patients (control group). Basic clinical data and serum 25-OH-VD, TNF-α, IL-6, IL-8, and IL-1ß of the 2 groups were compared by SPSS 25.0. A CHD rat model was used to explore the potential molecular mechanisms. RESULTS The serum 25-OH-VD level in the control group was significantly higher compared to the CHD group, and decreased with the worsening of the CHD condition. Logistic regression found that serum 25-OH-VD was a protective factor in the occurrence of CHD. In CHD patients, the level of serum 25-OH-VD had a negative correlation with serum TNF-α (r=-0.651, P<0.001), IL-6 (r=-0.457, P<0.001), IL-8 (r=-0.755, P<0.001), and IL-1ß (r=-0.628, P<0.001). In animal experiments, VD deficiency enhanced the level of serum TC, TG, and LDL-C. VD deficiency could increase the inflammatory response by upregulating the expression of p65 protein and reducing SIRT1 protein expression in heart tissue, thereby inducing or aggravating the state of CHD. CONCLUSIONS Serum 25-OH-VD was a protective factor in the occurrence of CHD, and VD deficiency could induce or aggravate the state of CHD by enhancing inflammation through the NF-κB pathway.


Subject(s)
Coronary Disease/complications , Vitamin D Deficiency/physiopathology , Aged , Animals , China , Disease Models, Animal , Female , Humans , Inflammation/physiopathology , Interleukin-1beta/blood , Interleukin-6/blood , Interleukin-8/blood , Male , Middle Aged , NF-kappa B/metabolism , Rats , Rats, Sprague-Dawley , Risk Factors , Sirtuin 1/metabolism , Tumor Necrosis Factor-alpha/blood , Vitamin D/analysis , Vitamin D/blood
13.
Int J Immunopathol Pharmacol ; 30(4): 406-412, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29164959

ABSTRACT

This study aimed to exploit the potential therapeutic value of palmatine in treatment of cardiac hypertrophy and the underlying molecular mechanism. Rat hypertrophy model was established by intraperitoneal isoproterenol (ISO) injection. The hypertrophy was evaluated with cardiac hypertrophic parameters, hemodynamic parameters, lipid profile, and non-specific cardiac markers. The animals were intraperitoneally administrated with either palmatine or vehicle. The relative expressions of ANP, BNP, HDAC2, HDAC5, KLF4, and INPP5F transcripts were determined by real-time polymerase chain reaction (PCR). The relative protein levels of HDAC2, HDAC5, KLF4, and INPP5F were analyzed by immunoblotting. Palmatine treatment significantly attenuated ISO-induced hypertrophy in rats and elicited remarkable repressions in ANP, BNP, and HDAC2 transcriptions but not HDAC5. The downstream effector genes KLF4 and INPP5F were greatly restored in a dose-dependent manner in response to palmatine treatment. Our data demonstrated that palmatine possessed promising therapeutic potential against hypertrophy, which was mediated by modulation of HDAC2-KLF4/INPP5F pathway.


Subject(s)
Berberine Alkaloids/pharmacology , Cardiomegaly/genetics , Cardiotonic Agents/pharmacology , Histone Deacetylase Inhibitors/pharmacology , Animals , Atrial Natriuretic Factor/genetics , Berberine Alkaloids/therapeutic use , Cardiomegaly/chemically induced , Cardiomegaly/drug therapy , Cardiomegaly/metabolism , Cardiotonic Agents/therapeutic use , Histone Deacetylase 2/antagonists & inhibitors , Histone Deacetylase 2/genetics , Histone Deacetylase Inhibitors/therapeutic use , Inositol Polyphosphate 5-Phosphatases/genetics , Isoproterenol , Kruppel-Like Factor 4 , Kruppel-Like Transcription Factors/genetics , Male , Natriuretic Peptide, Brain/genetics , RNA, Messenger/metabolism , Rats, Wistar
14.
Sci Rep ; 7(1): 13941, 2017 10 24.
Article in English | MEDLINE | ID: mdl-29066844

ABSTRACT

Each year ~5.4 million children and adolescents in the United States suffer from dental infections, leading to pulp necrosis, arrested tooth-root development and tooth loss. Apical revascularization, adopted by the American Dental Association for its perceived ability to enable postoperative tooth-root growth, is being accepted worldwide. The objective of the present study is to perform a meta-analysis on apical revascularization. Literature search yielded 22 studies following PRISMA with pre-defined inclusion and exclusion criteria. Intraclass correlation coefficient was calculated to account for inter-examiner variation. Following apical revascularization with 6- to 66-month recalls, root apices remained open in 13.9% cases (types I), whereas apical calcification bridge formed in 47.2% (type II) and apical closure (type III) in 38.9% cases. Tooth-root lengths lacked significant postoperative gain among all subjects (p = 0.3472) or in subgroups. Root-dentin area showed significant increases in type III, but not in types I or II cases. Root apices narrowed significantly in types II and III, but not in type I patients. Thus, apical revascularization facilitates tooth-root development but lacks consistency in promoting root lengthening, widening or apical closure. Post-operative tooth-root development in immature permanent teeth represents a generalized challenge to regenerate diseased pediatric tissues that must grow to avoid organ defects.


Subject(s)
Necrosis/therapy , Regenerative Medicine/methods , Tooth/pathology , Humans
15.
Chem Commun (Camb) ; 53(76): 10544-10547, 2017 Sep 21.
Article in English | MEDLINE | ID: mdl-28890982

ABSTRACT

The oxygen evolution reaction (OER) is the rate-limiting process for water splitting, and highly efficient large-area OER photoanodes have been considered as an essential part in photoelectrochemical water splitting reactors. The high hole-electron separation efficiency of photoanodes is highly required for real applications of photoanodes in sufficiently harvesting solar energy. Herein we show that the inactive g-C3N4 nanolayers can be self-assembled with BiVO4 into a highly coupled BV/CN dyad to significantly enhance the charge separation efficiency of BiVO4 photoelectrodes for the OER. The incident photon-to-current conversion efficiency (IPCE) of visible light (400 nm) provided by the scalable BV/CN-5 photoanode was estimated to be 50% at 1.23 V vs. RHE in 0.5 M Na2SO4 solution and significantly increased to 97% at a bias voltage of 1.6 V vs. RHE.

17.
Acta Biomater ; 17: 16-25, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25644451

ABSTRACT

Hydroxyapatite (HA) reinforced collagen scaffolds have shown promise for synthetic bone graft substitutes and tissue engineering scaffolds. Freeze-dried HA-collagen scaffolds are readily fabricated and have exhibited osteogenicity in vivo, but are limited by an inherent scaffold architecture that results in a relatively small pore size and weak mechanical properties. In order to overcome these limitations, HA-collagen scaffolds were prepared by compression molding HA reinforcements and paraffin microspheres within a suspension of concentrated collagen fibrils (∼ 180 mg/mL), cross-linking the collagen matrix, and leaching the paraffin porogen. HA-collagen scaffolds exhibited an architecture with high porosity (85-90%), interconnected pores ∼ 300-400 µm in size, and struts ∼ 3-100 µm in thickness containing 0-80 vol% HA whisker or powder reinforcements. HA reinforcement enabled a compressive modulus of up to ∼ 1 MPa, which was an order of magnitude greater than unreinforced collagen scaffolds. The compressive modulus was also at least one order of magnitude greater than comparable freeze-dried HA-collagen scaffolds and two orders of magnitude greater than absorbable collagen sponges used clinically. Moreover, scaffolds reinforced with up to 60 vol% HA exhibited fully recoverable elastic deformation upon loading to 50% compressive strain for at least 100,000 cycles. Thus, the scaffold mechanical properties were well-suited for surgical handling, fixation, and bearing osteogenic loads during bone regeneration. The scaffold architecture, permeability, and composition were shown to be conducive to the infiltration and differentiation of adipose-derive stromal cells in vitro. Acellular scaffolds were demonstrated to induce angiogenesis and osteogenesis after subcutaneous ectopic implantation by recruiting endogenous cell populations, suggesting that the scaffolds were osteoinductive.


Subject(s)
Biocompatible Materials/chemistry , Collagen/chemistry , Durapatite/chemistry , Tissue Scaffolds , Adipose Tissue/cytology , Adipose Tissue/metabolism , Animals , Bone Transplantation , Cattle , Freezing , Humans , Neovascularization, Physiologic , Osteogenesis , Paraffin/chemistry , Powders , Pressure , Stress, Mechanical , Tissue Engineering/methods
18.
J Biomed Mater Res A ; 103(3): 1053-9, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24889905

ABSTRACT

Native porcine nucleus pulposus (NP) tissue harbors a number of notochordal cells (NCs). Whether the native NP matrix supports the homeostasis of notochordal cells is poorly understood. We hypothesized the NP matrix alone may contain sufficient regulatory factors and can serve as stimuli to generate notochordal cells (NCs) from human pluripotent stem cells. NCs are a promising cell sources for cell-based therapy to treat some types of intervertebral disc (IVD) degeneration. One major limitation of this emerging technique is the lack of available NCs as a potential therapeutic cell source. Human pluripotent stem cells derived from reprogramming or somatic cell nuclear transfer technique may yield stable and unlimited source for therapeutic use. We devised a new method to use porcine NP matrix to direct notochordal differentiation of human induced pluripotent stem cells (hiPSCs). The results showed that hiPSCs successfully differentiated into NC-like cells under the influence of devitalized porcine NP matrix. The NC-like cells expressed typical notochordal marker genes including brachyury (T), cytokeratin-8 (CK-8) and cytokeratin-18 (CK-18), and they displayed the ability to generate NP-like tissue in vitro, which was rich in aggrecan and collagen type II. These findings demonstrated the proof of concept for using native NP matrix to direct notochordal differentiation of hiPSCs. It provides a foundation for further understanding the biology of NCs, and eventually towards regenerative therapies for disc degeneration.


Subject(s)
Cell Differentiation , Extracellular Matrix/chemistry , Induced Pluripotent Stem Cells/metabolism , Intervertebral Disc Degeneration/therapy , Intervertebral Disc/chemistry , Animals , Antigens, Differentiation/biosynthesis , Cell Line , Humans , Induced Pluripotent Stem Cells/cytology , Notochord/cytology , Notochord/metabolism , Swine
19.
Stem Cells Transl Med ; 3(10): 1125-37, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25122686

ABSTRACT

The use of human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) for study and treatment of bone diseases or traumatic bone injuries requires efficient protocols to differentiate hESCs/iPSCs into cells with osteogenic potential and the ability to isolate differentiated osteoblasts for analysis. We have used zinc finger nuclease technology to deliver a construct containing the Col2.3 promoter driving GFPemerald to the AAVS1 site (referred to as a "safe harbor" site), in human embryonic stem cells (H9Zn2.3GFP), with the goal of marking the cells that have become differentiated osteoblasts. In teratomas formed using these cells, we identified green fluorescent protein (GFP)-positive cells specifically associated with in vivo bone formation. We also differentiated the cells into a mesenchymal stem cell population with osteogenic potential and implanted them into a mouse calvarial defect model. We observed GFP-positive cells associated with alizarin complexone-labeled newly formed bone surfaces. The cells were alkaline phosphatase-positive, and immunohistochemistry with human specific bone sialoprotein (BSP) antibody indicates that the GFP-positive cells are also associated with the human BSP-containing matrix, demonstrating that the Col2.3GFP construct marks cells in the osteoblast lineage. Single-cell cloning generated a 100% Col2.3GFP-positive cell population, as demonstrated by fluorescence in situ hybridization using a GFP probe. The karyotype was normal, and pluripotency was demonstrated by Tra1-60 immunostaining, pluripotent low density reverse transcription-polymerase chain reaction array and embryoid body formation. These cells will be useful to develop optimal osteogenic differentiation protocols and to isolate osteoblasts from normal and diseased iPSCs for analysis.


Subject(s)
Embryonic Stem Cells/cytology , Green Fluorescent Proteins , Osteoblasts/cytology , Animals , Bone Matrix/cytology , Cell Differentiation/physiology , Collagen Type I/genetics , Collagen Type I, alpha 1 Chain , Genes, Reporter , Heterografts , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Mice , Pluripotent Stem Cells/cytology , Rats
20.
PLoS One ; 9(7): e100885, 2014.
Article in English | MEDLINE | ID: mdl-25054208

ABSTRACT

Human induced pluripotent stem cells (hiPSCs) can differentiate into notochordal cell (NC)-like cells when cultured in the presence of natural porcine nucleus pulposus (NP) tissue matrix. The method promises massive production of high-quality, functional cells to treat degenerative intervertebral discs (IVDs). Based on our previous work, we further examined the effect of cell-NP matrix contact and culture medium on the differentiation, and further assessed the functional differentiation ability of the generated NC-like. The study showed that direct contact between hiPSCs and NP matrix can promote the differentiation yield, whilst both the contact and non-contact cultures can generate functional NC-like cells. The generated NC-like cells are highly homogenous regarding the expression of notochordal marker genes. A culture medium containing a cocktail of growth factors (FGF, EGF, VEGF and IGF-1) also supported the notochordal differentiation in the presence of NP matrix. The NC-like cells showed excellent functional differentiation ability to generate NP-like tissue which was rich in aggrecan and collagen type II; and particularly, the proteoglycan to collagen content ratio was as high as 12.5-17.5 which represents a phenotype close to NP rather than hyaline cartilage. Collectively, the present study confirmed the effectiveness and flexibility of using natural NP tissue matrix to direct notochordal differentiation of hiPSCs, and the potential of using the generated NC-like cells for treating IVD degeneration.


Subject(s)
Cell Differentiation/physiology , Induced Pluripotent Stem Cells/cytology , Intervertebral Disc/metabolism , Notochord/cytology , Aggrecans/genetics , Aggrecans/metabolism , Animals , Cell Differentiation/drug effects , Cells, Cultured , Collagen Type II/genetics , Collagen Type II/metabolism , Culture Media/pharmacology , Epidermal Growth Factor/pharmacology , Fibroblast Growth Factors/pharmacology , Gene Expression/drug effects , Humans , Immunohistochemistry , Induced Pluripotent Stem Cells/drug effects , Insulin-Like Growth Factor I/pharmacology , Keratin-18/genetics , Keratin-18/metabolism , Keratin-8/genetics , Keratin-8/metabolism , Notochord/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Swine , Tissue Extracts/metabolism , Tissue Extracts/pharmacology , Vascular Endothelial Growth Factor A/pharmacology
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