Orthopedic implants containing biodegradable magnesium have been used for fracture repair with considerable efficacy; however, the underlying mechanisms by which these implants improve fracture healing remain elusive. Here we show the formation of abundant new bone at peripheral cortical sites after intramedullary implantation of a pin containing ultrapure magnesium into the intact distal femur in rats. This response was accompanied by substantial increases of neuronal calcitonin gene-related polypeptide-α (CGRP) in both the peripheral cortex of the femur and the ipsilateral dorsal root ganglia (DRG). Surgical removal of the periosteum, capsaicin denervation of sensory nerves or knockdown in vivo of the CGRP-receptor-encoding genes Calcrl or Ramp1 substantially reversed the magnesium-induced osteogenesis that we observed in this model. Overexpression of these genes, however, enhanced magnesium-induced osteogenesis. We further found that an elevation of extracellular magnesium induces magnesium transporter 1 (MAGT1)-dependent and transient receptor potential cation channel, subfamily M, member 7 (TRPM7)-dependent magnesium entry, as well as an increase in intracellular adenosine triphosphate (ATP) and the accumulation of terminal synaptic vesicles in isolated rat DRG neurons. In isolated rat periosteum-derived stem cells, CGRP induces CALCRL-and RAMP1-dependent activation of cAMP-responsive element binding protein 1 (CREB1) and SP7 (also known as osterix), and thus enhances osteogenic differentiation of these stem cells. Furthermore, we have developed an innovative, magnesium-containing intramedullary nail that facilitates femur fracture repair in rats with ovariectomy-induced osteoporosis. Taken together, these findings reveal a previously undefined role of magnesium in promoting CGRP-mediated osteogenic differentiation, which suggests the therapeutic potential of this ion in orthopedics.

Hollow MnCo2O4 nanofibers as efficient oxidase mimics for sensitive detection of sulfite and l-cysteine have been developed.

BackgroundClass III malocclusion is a maxillofacial disorder that is characterised by a concave profile and can be attributed to both genetic inheritance and environmental factors. It is a clinical challenge due to our limited understanding of its aetiology. Revealing its prototypical diversity will contribute to our sequential exploration of the underlying aetiological information. The objective of this study was to characterize phenotypic variations of Class III malocclusion via a lateral cephalometric analysis in a community of Chinese individuals.MethodOne-hundred-and-forty-four individuals (58 males ≥18 and 86 females ≥16) with Class III malocclusion ranging from mild to severe were enrolled in this study. Principal component analysis and cluster analysis were performed using 61 lateral cephalometric measurements.ResultsSix principal components were discovered in the examined population and were responsible for 73.7 % of the variability. Four subtypes were revealed by cluster analysis. Subtype 1 included subjects with mild mandibular prognathism with a steep mandibular plane. Subjects in subtype 2 showed a combination of prognathic mandibular and retrusive maxillary with a flat or normal mandibular plane. Subtype 3 included individuals with purely severe mandibular prognathism and a normal mandibular plane. Individuals in subtype 4 had a mild maxillary deficiency and severe mandibular prognathism with the lowest mandibular plane angle.ConclusionThe six principal components extracted among the 61 variables improve our knowledge of lateral cephalometric analysis for diagnoses. We successfully identified four Class III malocclusion subtypes, indicating that cluster analysis could supplement the classification of Class III malocclusion among a Chinese population and may assist in our on-going genetic study.Electronic supplementary materialThe online version of this article (doi:10.1186/s13005-016-0127-8) contains supplementary material, which is available to authorized users.

A self-templated approach has been developed for the preparation of FeMnO3 nanoparticles filled in the hollow core of polypyrrole (PPy) nanotubes by an in situ polymerization process accompanied by the etching of FeMnO3 nanofibers. The prepared FeMnO3@PPy nanotubes exhibited a superior peroxidase-like activity. The catalytic reaction system has been used for the sensitive colorimetric detection of glutathione with a low detection limit and good selectivity.

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Doping with transition metal ions has been regarded as one of the most effective means to optimize the catalytic efficiency of metal oxides. In this work, a general approach for the fabrication of Mo 6+ -doped Co 3 O 4 (Mo− Co 3 O 4 ) nanotubes for peroxidase mimicking has been demonstrated via an electrospinning method combined with a calcination process. The prepared Mo−Co 3 O 4 nanotubes exhibited a higher peroxidase-like catalytic activity than pure Co 3 O 4 nanotubes, and the highest catalytic activity is achieved when the molar fraction of Mo is 2.0%. The catalytic kinetic of Mo−Co 3 O 4 nanotubes follows a typical Michaelis−Menten mechanism, representing a strong affinity to H 2 O 2 and 3,3′,5,5′-tetramethylbenzidine (TMB) substrates. Because of the high catalytic efficiency of the Mo−Co 3 O 4 nanotubes, we have developed a facile and efficient strategy for the sensitive colorimetric determination of Lcysteine with a low detection limit of 24.2 nM. This detection limit is superior to many previous reported enzyme-like detection systems. Furthermore, a favorable selectivity toward the determination of Lcysteine based on this approach is also achieved, showing bright prospects in environmental monitoring and biomedical analysis.

Carbon dots/Fe3O4 hybrid nanofibers as efficient peroxidase mimics for sensitive detection of H2O2 and ascorbic acid have been developed.

This review provides an overview of emerging ultrafast synthesis technologies for energy and environmental applications. Representative ultrafast methods include Joule heating, plasma, laser, infrared, microwave, and flame-assisted synthesis, etc.