Effect of ultrafine poly(ε-caprolactone) fibers on calcium phosphate cement: in vitro degradation and in vivo regeneration.

We incorporated ultrafine polymer fibers into calcium phosphate cement (CPC) to improve the resorption rate of CPC with fiber degradation. Different weight percentages of electrospun poly(ε-caprolactone) fibers (0%, 3%, and 7%, named as ultrafine fiber-incorporated CPC0 [UFICPC0], UFICPC3, and UFICPC7) were included into preset CPC specimens for in vitro immersion in lipase phosphate-buffered solution and long-term in vivo implantation in the femoral condyle of rabbits. The effect of the ultrafine poly(ε-caprolactone) fibers with a diameter ranging from nanometer to micrometer on CPC degradation was evaluated by measuring the pH of the medium, mass loss, porosity, and physiochemical properties.

Bone regeneration and infiltration of an anisotropic composite scaffold: an experimental study of rabbit cranial defect repair.

Tissue formation on scaffold outer edges after implantation may restrict cell infiltration and mass transfer to/from the scaffold center due to insufficient interconnectivity, leading to incidence of a necrotic core. Herein, a nano-hydroxyapatite/polyamide66 (n-HA/PA66) anisotropic scaffold with axially aligned channels was prepared with the aim to enhance pore interconnectivity. Bone tissue regeneration and infiltration inside of scaffold were assessed by rabbit cranial defect repair experiments.

Differential susceptibility of transgenic mice expressing human surfactant protein B genetic variants to Pseudomonas aeruginosa induced pneumonia.

Surfactant protein B (SP-B) is essential for lung function. Previous studies have indicated that a SP-B 1580C/T polymorphism (SNP rs1130866) was associated with lung diseases including pneumonia. The SNP causes an altered N-linked glycosylation modification at Asn129 of proSP-B, e.

Osteogenic potential and synergistic effects of growth factors delivered from a bionic composite system.

Previous research has raised substantial controversy over the synergistic effects of exogenous growth factors, BMP-2 and bFGF, when used together for the treatment of bony defects. Thus, this study evaluated the effects of BMP-2 and bFGF at specified dose ratio composited with n-HA/PU40, a porous scaffold material, for repairing femoral defect in rats. Four weeks after implantation of this composite system, tissue specimens were collected for histological, immunohistochemical examinations, and µ-CT scanning.

Effects of graphene oxide nanosheets on the ultrastructure and biophysical properties of the pulmonary surfactant film.

Graphene oxide (GO) is the most common derivative of graphene and has been used in a large range of biomedical applications. Despite considerable progress in understanding its cytotoxicity, its potential inhalation toxicity is still largely unknown. As the pulmonary surfactant (PS) film is the first line of host defense, interaction with the PS film determines the fate of the inhaled nanomaterials and their potential toxicity.

Hierarchical Structure and Mechanical Improvement of an n-HA/GCO-PU Composite Scaffold for Bone Regeneration.

To improve the mechanical properties of bone tissue and achieve the desired bone tissue regeneration for orthopedic surgery, newly designed hydroxyapatite/polyurethane (HA/PU) porous scaffolds were developed via in situ polymerization. The results showed that the molecular modification of PU soft segments by glyceride of castor oil (GCO) can increase the scaffold compressive strength by 48% and the elastic modulus by 96%. When nano-HA (n-HA) particles were incorporated into the GCO-PU matrix, the compressive strength and elastic modulus further increased by 49 and 74%, from 2.

Crucial Role of Lateral Size for Graphene Oxide in Activating Macrophages and Stimulating Pro-inflammatory Responses in Cells and Animals.

Graphene oxide (GO) is increasingly used in biomedical applications because it possesses not only the unique properties of graphene including large surface area and flexibility but also hydrophilicity and dispersibility in aqueous solutions. However, there are conflicting results on its biocompatibility and biosafety partially due to large variations in physicochemical properties of GO, and the role of these properties including lateral size in the biological or toxicological effects of GO is still unclear. In this study, we focused on the role of lateral size by preparing a panel of GO samples with differential lateral sizes using the same starting material.

Fabrication and Osteogenesis of a Porous Nanohydroxyapatite/Polyamide Scaffold with an Anisotropic Architecture.

Scaffolds are used in bone tissue engineering to provide a temporary structural template for cell seeding and extracellular matrix formation. However, tissue formation on scaffold outer edges after implantation due to insufficient interconnectivity may restrict cell infiltration and mass transfer to/from the scaffold center, leading to bone regeneration failure. To address this problem, we prepared nanohydroxyapatite/polyamide66 (n-HA/PA66) anisotropic scaffolds with axially aligned channels (300 μm) with the aim to enhance pore interconnectivity and subsequent cell and tissue infiltration throughout the scaffold.

Long-chain Acylcarnitines Reduce Lung Function by Inhibiting Pulmonary Surfactant.

The role of mitochondrial energy metabolism in maintaining lung function is not understood. We previously observed reduced lung function in mice lacking the fatty acid oxidation enzyme long-chain acyl-CoA dehydrogenase (LCAD). Here, we demonstrate that long-chain acylcarnitines, a class of lipids secreted by mitochondria when metabolism is inhibited, accumulate at the air-fluid interface in LCAD(-/-) lungs.

Complete Genomic Characterization of Porcine Reproductive and Respiratory Syndrome Virus Strain HB-XL.

Porcine reproductive and respiratory syndrome virus (PRRSV) is the causal agent of a serious disease of swine. Here, we report the genome sequence of PRRSV strain HB-XL isolated from a pig farm with a clinical outbreak of porcine reproductive and respiratory syndrome. The genome is 15,323 bp long and has nine open reading frames (GenBank: KP162169).

Device characterization and optimization of small molecule organic solar cells assisted by modelling simulation of the current-voltage characteristics.

In order to understand the photovoltaic performance differences between the recently reported DR3TBTT-HD and DR3TBDT2T based solar cells, a modified two-diode model with Hecht equation was built to simulate the corresponding current-voltage characteristics. The simulation results reveal that the poor device performance of the DR3TBDTT-HD based device mainly originated from its insufficient charge transport ability, where an average current of 5.79 mA cm(-2) was lost through this pathway at the maximum power point for the DR3TBDTT-HD device, nearly three times as large as that of the DR3TBDT2T based device under the same device fabrication conditions.

Biophysical influence of airborne carbon nanomaterials on natural pulmonary surfactant.

Inhalation of nanoparticles (NP), including lightweight airborne carbonaceous nanomaterials (CNM), poses a direct and systemic health threat to those who handle them. Inhaled NP penetrate deep pulmonary structures in which they first interact with the pulmonary surfactant (PS) lining at the alveolar air-water interface. In spite of many research efforts, there is a gap of knowledge between in vitro biophysical study and in vivo inhalation toxicology since all existing biophysical models handle NP-PS interactions in the liquid phase.

Quantitatively predicting bacterial adhesion using surface free energy determined with a spectrophotometric method.

Bacterial adhesion onto solid surfaces is of importance in a wide spectrum of problems, including environmental microbiology, biomedical research, and various industrial applications. Despite many research efforts, present thermodynamic models that rely on the evaluation of the adhesion energy are often elusive in predicting the bacterial adhesion behavior. Here, we developed a new spectrophotometric method to determine the surface free energy (SFE) of bacterial cells.

Development and in vitro characterization of drug delivery system of rifapentine for osteoarticular tuberculosis.

The study was to develop and evaluate the rifapentine-loaded poly(lactic acid-co-glycolic acid) (PLGA) microspheres (RPMs) for the treatment of osteoarticular tuberculosis to avoid critical side effects caused by oral regimens of antibiotics or intravenous antibiotics. The RPMs were spherical with rough surfaces, and elevated amounts of rifapentine in the formulation markedly increased the particle size and drug loading, while decreased the size distribution and entrapment efficiency. The highest drug loading and encapsulation efficiency of RPMs were 23.

Fixed-dose combination treatment after stroke for secondary prevention in China: a national community-based study.

Background And Purpose: There is evidence and international consensus on the advantages and potential of a polypill for established cardiovascular disease patients to improve adherence in the secondary prevention of cardiovascular disease. This study aimed to estimate the numbers of stroke patients who would be eligible for the polypill strategy in China, and the suitable composition of a polypill, based on data of the China National Stroke Prevention Project.

Methods: A total of 717 620 residents aged ≥40 years from 6 Chinese representative provinces were screened for prevalent stroke from 2011 to 2012 with an 84.

Osteogenesis and chondrogenesis of biomimetic integrated porous PVA/gel/V-n-HA/pa6 scaffolds and BMSCs construct in repair of articular osteochondral defect.

A novel bi-layered osteochondral scaffold, including of PVA/Gel/V layer for the cartilage and n-HA/PA6 layer for the subchondral bone, has been proposed to evaluate the potential of the engineered of osteochondral grafts in repairing articular osteochondral defects in rabbits. The two different layers of the scaffolds were seeded with allogenic bone marrow-derived stem cells (BMSCs), which were chondrogenically and osteogenically induced respectively. The critical-size osteochondral defects were created in the knees of adult rabbits.

Antimicrobial and biophysical properties of surfactant supplemented with an antimicrobial peptide for treatment of bacterial pneumonia.

Antibiotic-resistant bacterial infections represent an emerging health concern in clinical settings, and a lack of novel developments in the pharmaceutical pipeline is creating a "perfect storm" for multidrug-resistant bacterial infections. Antimicrobial peptides (AMPs) have been suggested as future therapeutics for these drug-resistant bacteria, since they have potent broad-spectrum activity, with little development of resistance. Due to the unique structure of the lung, bacterial pneumonia has the additional problem of delivering antimicrobials to the site of infection.

A series of simple oligomer-like small molecules based on oligothiophenes for solution-processed solar cells with high efficiency.

A series of acceptor-donor-acceptor simple oligomer-like small molecules based on oligothiophenes, namely, DRCN4T-DRCN9T, were designed and synthesized. Their optical, electrical, and thermal properties and photovoltaic performances were systematically investigated. Except for DRCN4T, excellent performances were obtained for DRCN5T-DRCN9T.

Physicochemical and biological properties of a novel injectable polyurethane system for root canal filling.

A root canal sealer with antibacterial activity can be efficacious in preventing reinfection that results from residual microorganisms and/or the leakage of microorganisms. In the present study, a series of injectable, self-curing polyurethane (PU)-based antibacterial sealers with different concentrations of silver phosphate (Ag3PO4) were fabricated. Subsequently, their physicochemical properties, antibacterial abilities, and preliminary cytocompatibilities were evaluated.

Shape affects the interactions of nanoparticles with pulmonary surfactant.

The interactions with the pulmonary surfactant, the initial biological barrier of respiratory pathway, determine the potential therapeutic applications and toxicological effects of inhaled nanoparticles (NPs). Although much attention has been paid to optimize the physicochemical properties of NPs for improved delivery and targeting, shape effects of the inhaled NPs on their interactions with the pulmonary surfactant are still far from clear. Here, we studied the shape effects of NPs on their penetration abilities and structural disruptions to the dipalmitoyl-phosphatidylcholine (DPPC) monolayer (being model pulmonary surfactant film) using coarse-grained molecular dynamics simulations.

Complete Genome Sequence of Porcine Circovirus Type 2 Strain HB-MC1.

Porcine circovirus type 2 (PCV2) is the primary causative agent of porcine circovirus-associated disease (PCVAD). Here, we report the complete genome sequence of PCV2 strain HB-MC1, which belongs to PCV2d.

Gradient control of the adhesive force between Ti/TiO2 nanotubular arrays fabricated by anodization.

The poor control of the adhesion of TiO2 nanotubes (TNTs) layers to a non-anodized titanium (Ti) substrate has limited their widespread application, because the stripping mechanism has not yet been revealed. Here, we report a novel method to control the detachment of TNTs by post-treatment of the as-fabricated samples in protic and aprotic solvents with different polarities. Post-treatment using an organic solvent of lower polarity increases the adhesion of the tube layer, in contrast to the spontaneous detachment of the TNT layer after treatment using a solvent of higher polarity.

Biological evaluation of porous aliphatic polyurethane/hydroxyapatite composite scaffolds for bone tissue engineering.

Biomaterial scaffolds meant to function as supporting structures to osteogenic cells play a pivotal role in bone tissue engineering. Recently, we synthesized an aliphatic polyurethane (PU) scaffold via a foaming method using non-toxic components. Through this procedure a uniform interconnected porous structure was created.

Development of porous polyurethane/strontium-substituted hydroxyapatite composites for bone regeneration.

Polyurethane (PU) has been widely used for the biomedical applications but its potential for bone regeneration is limited due to its lack of osteoconductive properties. Strontium substituted hydroxyapatite (SrHA) particles, on the other hand, are known to exhibit a positive effect on bone formation. Therefore, the aim of this study was to (i) develop porous polyurethane scaffolds containing strontium SrHA nanoparticles (PU/SrHA) and (ii) compare their in vitro biological performance for applications in bone regeneration to PU scaffolds.