Ambient ozone exposure and bone turnover markers in children: Results from the GINIplus and LISA birth cohorts.

Background: Multiple environmental factors can regulate bone metabolism, and it is hypothesized that air pollution may be deleteriously involved in this regulation. However, only a few studies considered bone turnover markers (BTMs) - sensitive and specific markers of bone metabolism - as outcomes, and no study investigated the exposure to ambient ozone. Here, we intended to explore the associations between long-term exposure to ambient ozone and concentrations of two BTMs, osteocalcin and β-isomer of C-terminal telopeptide of type I collagen (CTx), amongst 10-year-old children.

A neurovascular-unit-on-a-chip for the evaluation of the restorative potential of stem cell therapies for ischaemic stroke.

The therapeutic efficacy of stem cells transplanted into an ischaemic brain depends primarily on the responses of the neurovascular unit. Here, we report the development and applicability of a functional neurovascular unit on a microfluidic chip as a microphysiological model of ischaemic stroke that recapitulates the function of the blood-brain barrier as well as interactions between therapeutic stem cells and host cells (human brain microvascular endothelial cells, pericytes, astrocytes, microglia and neurons). We used the model to track the infiltration of a number of candidate stem cells and to characterize the expression levels of genes associated with post-stroke pathologies.

A versatile system to record cell-cell interactions.

Cell-cell interactions influence all aspects of development, homeostasis, and disease. In cancer, interactions between cancer cells and stromal cells play a major role in nearly every step of carcinogenesis. Thus, the ability to record cell-cell interactions would facilitate mechanistic delineation of the role of the cancer microenvironment.

[Bioinformatic analysis of Eftud2 enhancing mouse macrophage function].

Objective To elucidate the mechanisms by which elongation factor Tu GTP binding domain containing 2 (Eftud2) enhances the immune function of murine macrophages by bioinformatics analysis. Methods The bone marrow-derived macrophages (BMDMs) of Eftud2 myeloid cell-specific knockout (MKO) mice (n=10) and wild-type (WT) littermates (n=10) were collected and stimulated by lipopolysaccharide (LPS) (100 ng/mL) for 2 hours. Bioinformatics analysis was conducted to examine the differences in gene expression and mRNA transcription levels.

Epithelial-to-Mesenchymal Transition (EMT) and Drug Response in Dynamic Bioengineered Lung Cancer Microenvironment.

Tumor microenvironment and the interplay of physical and mechanical forces are key determinants of cancer initiation, progression, and response to drug treatment. However, the impact of tumor microenvironment on cancer progression is poorly understood, in large due to the lack of in vitro models that recapitulate the physical aspects of tumor microenvironment. Herein, a simple, dynamic 3D nonsmall cell lung carcinoma culture using a multichannel microfluidic model platform is developed for evaluating the contribution of flow-induced hydrodynamic shear stress on epithelial-to-mesenchymal transition (EMT).

Sulfonate Groups and Saccharides as Essential Structural Elements in Heparin-Mimicking Polymers Used as Surface Modifiers: Optimization of Relative Contents for Antithrombogenic Properties.

Blood compatibility is a long sought-after goal in biomaterials research, but remains an elusive one, and in spite of extensive work in this area, there is still no definitive information on the relationship between material properties and blood responses such as coagulation and thrombus formation. Materials modified with heparin-mimicking polymers have shown promise and indeed may be seen as comparable to materials modified with heparin itself. In this work, heparin was conceptualized as consisting of two major structural elements: saccharide- and sulfonate-containing units, and polymers based on this concept were developed.

Deciphering the Role of Sulfonated Unit in Heparin-Mimicking Polymer to Promote Neural Differentiation of Embryonic Stem Cells.

Glycosaminoglycans (GAGs), especially heparin and heparan sulfate (HS), hold great potential for inducing the neural differentiation of embryonic stem cells (ESCs) and have brought new hope for the treatment of neurological diseases. However, the disadvantages of natural heparin/HS, such as difficulty in isolating them with a sufficient amount, highly heterogeneous structure, and the risk of immune responses, have limited their further therapeutic applications. Thus, there is a great demand for stable, controllable, and well-defined synthetic alternatives of heparin/HS with more effective biological functions.

Intracellular Delivery Platform for "Recalcitrant" Cells: When Polymeric Carrier Marries Photoporation.

The intracellular delivery of exogenous macromolecules is of great interest for both fundamental biological research and clinical applications. Although traditional delivery systems based on either carrier mediation or membrane disruption have some advantages; however, they are generally limited with respect to delivery efficiency and cytotoxicity. Herein, a collaborative intracellular delivery platform with excellent comprehensive performance is developed using polyethylenimine of low molecular weight (LPEI) as a gene carrier in conjunction with a gold nanoparticle layer (GNPL) acting as a photoporation agent.

Promoting neural differentiation of embryonic stem cells using β-cyclodextrin sulfonate.

A heparin-mimicking biomolecule, β-cyclodextrin decorated with sulfonate groups (CD-S), was synthesized. CD-S itself exhibited bioactivity similar to that of heparin and can further serve as a carrier for all-trans retinoic acid by forming inclusion complexes that promote neural differentiation of embryonic stem cells more effectively than heparin.

Synthetic Glycopolymers for Highly Efficient Differentiation of Embryonic Stem Cells into Neurons: Lipo- or Not?

To realize the potential application of embryonic stem cells (ESCs) for the treatment of neurodegenerative diseases, it is a prerequisite to develop an effective strategy for the neural differentiation of ESCs so as to obtain adequate amount of neurons. Considering the efficacy of glycosaminoglycans (GAG) and their disadvantages (e.g.

A hemocompatible polyurethane surface having dual fibrinolytic and nitric oxide generating functions.

Thrombus formation remains a serious problem in developing blood compatible materials. Despite continuous, intensive efforts over many years to prepare surfaces that prevent clotting, such surfaces have not been achieved; indeed it seems that surface-induced clotting is inevitable. An alternative approach is to accept that clotting will occur and to design surfaces so that small, nascent clots will be lysed before they can cause harm.

Glycosaminoglycans (GAGs) and GAG mimetics regulate the behavior of stem cell differentiation.

Glycosaminoglycans (GAGs) are linear sulfated polysaccharides that exist in most mammalian cells. By undergoing conjugation with various proteins, GAGs play important roles in a variety of bioactivities, including promoting stem cell differentiation. However, they have their own intrinsic disadvantages that limit their further applications for cell therapy and tissue engineering.

A new avenue to the synthesis of GAG-mimicking polymers highly promoting neural differentiation of embryonic stem cells.

A new strategy for the fabrication of glycosaminoglycan (GAG) analogs was proposed by copolymerizing the sulfonated unit and the glyco unit, 'splitted' from the sulfated saccharide building blocks of GAGs. The synthetic polymers can promote cell proliferation and neural differentiation of embryonic stem cells with the effects even better than those of heparin.

Enzyme-triggered supramolecular self-assembly of platinum prodrug with enhanced tumor-selective accumulation and reduced systemic toxicity.

We report the generation of a novel self-assembled platinum (Pt) prodrug from a short peptide derivative, which acted as a substrate for the phosphatase-catalyzed dephosphorylation reaction, and a Pt(iv) complex, which could undergo supramolecular self-assembly in the presence of alkaline phosphatase, and perform controlled release of the Pt(ii) drug under the reductive conditions of tumor cells. This self-assembled prodrug showed significant antitumor growth effects on a breast cancer xenograft model based on 4T1 cells in vivo, but much lower toxicity towards the kidney, liver, spleen and other major organs than the free cisplatin drug in mice. Such improved antitumor efficacy could be ascribed to the localized and sustained release of the Pt(ii) anticancer drug from the supramolecular self-assembly of the Pt(iv) prodrug, which was triggered by phosphatases in tumor sites.

6-O-sulfated chitosan promoting the neural differentiation of mouse embryonic stem cells.

Embryonic stem cells (ESCs) can be induced to differentiate into nerve cells, endowing them with potential applications in the treatment of neurological diseases and neural repair. In this work, we report for the first time that sulfated chitosan can promote the neural differentiation of ESCs. As a type of sulfated glycosaminoglycan analog, sulfated chitosan with well-defined sulfation sites and a controlled degree of sulfation (DS) were prepared through simple procedures and the influence of sulfated glycosaminoglycan on neural differentiation of ESCs was investigated.

Stimulation of gene transfection by silicon nanowire arrays modified with polyethylenimine.

In this work, a novel gene delivery strategy was proposed based on silicon nanowire arrays modified with high-molecular-weight 25 kDa branched polyethylenimine (SN-PEI). Both the plasmid DNA (pDNA) binding capacity and the in vitro gene transfection efficiency of silicon nanowire arrays (SiNWAs) were significantly enhanced after modification with high-molecular-weight bPEI. Moreover, the transfection efficiency was substantially further increased by the introduction of free pDNA/PEI complexes formed by low-molecular-weight branched PEI (bPEI, 2 kDa).

Maintaining the pluripotency of mouse embryonic stem cells on gold nanoparticle layers with nanoscale but not microscale surface roughness.

Efficient control of the self-renewal and pluripotency maintenance of embryonic stem cell (ESC) is a prerequisite for translating stem cell technologies to clinical applications. Surface topography is one of the most important factors that regulates cell behaviors. In the present study, micro/nano topographical structures composed of a gold nanoparticle layer (GNPL) with nano-, sub-micro-, and microscale surface roughnesses were used to study the roles of these structures in regulating the behaviors of mouse ESCs (mESCs) under feeder-free conditions.