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Due to their inherent hydrophobic and bioinert nature, synthetic degradable polymer-based membranes show inferior stem cell attachment, proliferation, and even differentiation. To overcome these limitations, bioinspired and osteopromotive polydopamine nanoparticle-incorporated fibrous membranes are developed via a two-step route: pH-induced polymerization of dopamine and co-electrospinning of polycaprolactone (PCL) with polydopamine nanoparticles (PDA NPs). Hybrid membranes with optimized PDA NP content exhibit high quantities of apatite deposition and prominent cytocompatibility (cell attachment, spreading and reproduction) and osteo-differentiation potential (alkaline phosphatase activity, calcium mineralization, and osteogenesis-related genes and protein expression) of human mesenchymal stem cells cultured without any growth factors. Importantly, in vivo assessments using a mouse calvarial critical-sized defect demonstrate that the engineered fibrous membranes remarkably boost bone reconstruction and regeneration. Accordingly, our bioinspired PCL-based hybrid fibrous membranes with robust osteoinductive ability can potentially be utilized as a clinically applicable candidate in guided tissue regeneration applications. Defects introduced into the skulls of mice can be repaired using a new fibrous membrane that expedites stem cell attachment and growth. Polydopamine is a promising compound for tethering biological substances to surfaces, similar to the adhesive proteins found in mussels. Dr. Yi Deng from the Peking University School and Hospital of Stomatology, and Sichuan University School of Chemical Engineering in China, and colleagues now report that coating biocompatible polymer membrane with polydopamine nanoparticles creates surfaces with numerous sites for calcium ions to attach and begin bone regeneration. The team incubated both coated and uncoated membranes with stem cells isolated from bone marrow and placed the membranes on skull bone defects in live mice. Investigations over a two-month period revealed that the sticky membranes could direct stem cells to produce significantly higher quantities of bone than uncoated membranes. To address the inherent hydrophobic and bioinert natures of synthetic polymeric membranes, we design and construct bioinspired and osteopromotive polydopamine nanoparticle-incorporated fibrous membranes through co-electrospinning of polycaprolactone (PCL) with polydopamine nanoparticles (PDA NPs). The multifunctional membranes are demonstrated to possess prominent cytocompatibility and osteo-differentiation potential of human mesenchymal stem cells (hMSCs) without any growth factors, as well as boosted bone regeneration in vivousing a mouse calvarial critical-sized defect. Accordingly, such engineered PDA/PCL fibrous membranes, which are osteoinductive and easy to transplant, have great potential for guided tissue regeneration application.

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To prepare alpha zirconium phosphate (α-ZrP) with high interlayer distance, grafting ratio and thermal stability, 1,2-epoxypropane was used to modify α-ZrP as the epoxy group reacting with P-OH on the external and internal surfaces of α-ZrP to form P-O-C bonds after small amines pre-intercalation. Different characterization techniques were used, including X-ray Powder Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Thermo-Gravimetric Analysis (TGA) and Carbon Mass Nuclear Magnetic Resonance (13C MAS NMR). The results of XRD confirmed the pre-intercalation of amino-propane and the intercalation of 1,2-epoxypropane, as the interlayer distance increased from 7.5 Å to 16.9 Å and 15.3 Å, respectively. FT-IR and 13C MAS NMR results confirmed the formation of P-O-C bonds between 1,2-epoxypropane and α-ZrP. TGA analysis showed that the grafting ratio of 1,2-epoxypropane was 19.44%.

•What is already known on this subject?High-dose dual therapy has acceptable eradication rates in some regions.•What are the new findings?High-dose dual treatments had high eradication rates comparable to quadruple therapy, with better adherence in Hainan Island.•How might it impact on clinical practice in the foreseeable future?. The answer is missing here:High-dose dual treatment is expected to be the first-line therapy to eradicate Helicobacter pylori.

Abstract. The purpose of the paper is study the tunnel air environment adjustment. We built a set-up according to the similarity law. Temperature, air flow velocity, and the humidity in the model tunnel were measured using a measurement system. Experimental data were obtained under the ventilation duct at the top of the tunnel. The results show that adjusting velocity and humidity of the supply air flow can satisfy the Safety Regulation for Metal and No-metal Mines.

Here we describe the clinical features and outcomes of patients with moyamoya disease who were surgically treated at a single institution in China.

A co-precipitation preparation method and the properties of an ultraviolet (UV)-attenuating agent are described in this paper. The composite particles of ultra-fine zinc oxide and titanium oxide are used to attenuate UV radiation. Preparation of TiOSO4, ZnCl2 solution and the co-precipitation of the composite particles by alkali are included during the process. Various types of surfactants have been used to modify the composite particles. Particle sizes are determined by laser particle analyzer, and reflectance and absorption coefficient are determined by UV-VIS spectrophotometer. Results show that particle size of the composite particles as well as total reflectance and absorption coefficient depend on the surfactants, pH value, and carline temperature. The average sizes of zinc oxide and titanium oxide ultra-fine particles range from39 to 65 nm. Attenuation capability of ultraviolet radiation becomes stronger when the particle average sizes becomes smaller. Composites less than 40 nm with titanium oxide of rutile phase attenuate most effectively the ultraviolet radiation ranging from 280 nm to 390 nm.

Bioactive composite of apatite-wollastonite(AW)/β-tricalcium phosphate (β-TCP) was prepared. The nucleation and growth of bio-apatite on the surface of AW/β-TCP ceramic in simulated body fluid (SBF) were investigated. The surface morphological structure, phase compositions and microstructure of the materials were characterized by scan electron microscopy (SEM), X-ray diffraction (XRD) and infrared spectroscopy (IR); Results show that the surfaces of the AW/β-TCP composite ceramic are covered with a layer of carbonate hydroxyapatite (HCA) when soaked in SBF, which indicates their bioactivity; Such HCA layer is composed of fine ball-like HA granules. With excellent bioactivity and bio-absorption, AW/β-TCP bioactive composite ceramic is expected to be a good candidate for bone substitutes and bone tissue engineering scaffolds.

Porous biodegradable scaffolds are widely used in bone tissue engineering to provide temporary templates for cellular attachment and matrix synthesis. Ideally, the degradation rate in vivo may be similar or slightly less than that of tissue formation, allowing for the maintenance of the scaffold structure and the mechanical support during early stages of tissue formation. Eventually, the 3-D spaces occupied by the porous scaffolds will be replaced by newly formed tissue. In this work, β-tricalcium phosphate/Poly-L lactide (β-TCP/PLLA) scaffolds with different proportions of β-TCP to PLLA were investigated. The effects of β-TCP proportions on degradation rate and mechanical strengths of the scaffolds were evaluated in simulated body fluid (SBF) at 37℃ up to 42 days. Results show that: different proportions of β-TCP to PLLA have significant influence on degradation behaviors of the scaffolds, and mechanical strengths of the scaffolds with weight proportion of β-TCP to PLLA being 2 to 1 are much higher than those of the others during the degradation period. And in this period, the scaffolds biodegrade slowly, and Hydroxyl Carbonate Apatite (HCA) forms in the surface of the material.

Merwinite powders were synthesized by a sol-gel process. The bioactivity in vitro of merwinite was investigated by soaking the powders in simulated body fluid (SBF), the growth of hydroxyapatite(HAp) on the surface of the powder was evaluated in various time. It was found that hydroxyapatite was formed after soaking for 14 days. The results indicate that merwinite possessed apatite-formation ability might be a potential candidate biomaterial for hard tissue repair.

Degradation of surface modified β-tricalcium phosphate (β-TCP) and poly L lactic acid (PLLA) composite scaffolds were investigated in vitro. Bending and compressive strengths were tested by electromechanical universal material testing machine. Molecular weight changes of lactic acid during degradation were measured by gel permeation chromatography (GPC). Phase composition of the surface after soaking was analyzed by Fourier transform infrared ray (FTIR). The surface and cross section of scaffold samples after degradation were observed by Scanning electron microscope (SEM).The results show that degradation speed can be controlled by adjusting the ratio of β-TCP to PLLA in the composite. PLLA can compound more closely with surface modified β-TCP than with non-modified one. The final compressive strength and bending strength of the scaffolds reach 7.11MPa and 2.20MPa respectively, which satisfies the need for bone tissue engineering scaffolds in clinic applications.

The porous apatite-wollastonite bioactive glass-ceramic (AW-GG) was made from nano-precursor powders derived from sol-gel process, and shaped by dipping method with polymer foam. The physical-chemical properties, bioactivity and biocompatibility of the materials were studied by means of TG, XRD, SEM, TEM and so on. The bioactivity was investigated in simulated body fluid (SBF) and the biocompatibility was evaluated by co-culturing with marrow stromal cells (MSCs). The result shows that: the particle size of the AW precursor powders is 40~100nm; porous AW GC has three-dimensional pored structure with 300~500um macropores and 2~5um micropores; the materials possess high bioactivity and biocompatibility. Porous AW GC may therefore have great potential application as bone tissue engineering scaffold.

Acute meningitis or encephalitis (AME) results from a neurological infection causing high case fatality and severe sequelae. AME lacked comprehensive surveillance in China.

Non pharmaceutical interventions (NPI) including hand washing directives were implemented in China and worldwide to combat the COVID-19 pandemic, which are likely to have had impacted a broad spectrum of enteric pathogen infections.

The purpose of this study was to investigate whether thyroid function and thyroid autoantibodies were associated with the risk of moyamoya disease in pediatric subjects.

Abstract: Spatial scan statistics are commonly used for geographical disease surveillance and cluster detection. While there are multiple clusters coexisting in the study area, they become difficult to detect because of clusters’ shadowing effect to each other. The recently proposed sequential method showed its better power for detecting the second weaker cluster, but did not improve the ability of detecting the first stronger cluster which is more important than the second one. We propose a new extension of the spatial scan statistic which could be used to detect multiple clusters. Through constructing two or more clusters in the alternative hypothesis, our proposed method accounts for other coexisting clusters in the detecting and evaluating process. The performance of the proposed method is compared to the sequential method through an intensive simulation study, in which our proposed method shows better power in terms of both rejecting the null hypothesis and accurately detecting the coexisting clusters. In the real study of hand-foot-mouth disease data in Pingdu city, a true cluster town is successfully detected by our proposed method, which cannot be evaluated to be statistically significant by the standard method due to another cluster’s shadowing effect. [Copyright &y& Elsevier]