22 research outputs found
Degradable Nanohydroxyapatite-Reinforced Superglue for Rapid Bone Fixation and Promoted Osteogenesis
Bone glue with robust adhesion is
crucial for treating
complicated
bone fractures, but it remains a formidable challenge to develop a
ātrueā bone glue with high adhesion strength, degradability,
bioactivity, and satisfactory operation time in clinical scenarios.
Herein, inspired by the hydroxyapatite and collagen matrix composition
of natural bone, we constructed a nanohydroxyapatite (nHAP) reinforced
osteogenic backbone-degradable superglue (O-BDSG) by in situ radical ring-opening polymerization. nHAP significantly enhances
adhesive cohesion by synergistically acting as noncovalent connectors
between polymer chains and increasing the molecular weight of the
polymer matrix. Moreover, nHAP endows the glue with bioactivity to
promote osteogenesis. The as-prepared glue presented a 9.79 MPa flexural
adhesion strength for bone, 4.7 times that without nHAP, and significantly
surpassed commercial cyanoacrylate (0.64 MPa). O-BDSG exhibited degradability
with 51% mass loss after 6 months of implantation. In vivo critical defect and tibia fracture models demonstrated the promoted
osteogenesis of the O-BDSG, with a regenerated bone volume of 75%
and mechanical function restoration to 94% of the native tibia after
8 weeks. The glue can be flexibly adapted to clinical scenarios with
a curing time window of about 3 min. This work shows promising prospects
for clinical application in orthopedic surgery and may inspire the
design and development of bone adhesives
Degradable Nanohydroxyapatite-Reinforced Superglue for Rapid Bone Fixation and Promoted Osteogenesis
Bone glue with robust adhesion is
crucial for treating
complicated
bone fractures, but it remains a formidable challenge to develop a
ātrueā bone glue with high adhesion strength, degradability,
bioactivity, and satisfactory operation time in clinical scenarios.
Herein, inspired by the hydroxyapatite and collagen matrix composition
of natural bone, we constructed a nanohydroxyapatite (nHAP) reinforced
osteogenic backbone-degradable superglue (O-BDSG) by in situ radical ring-opening polymerization. nHAP significantly enhances
adhesive cohesion by synergistically acting as noncovalent connectors
between polymer chains and increasing the molecular weight of the
polymer matrix. Moreover, nHAP endows the glue with bioactivity to
promote osteogenesis. The as-prepared glue presented a 9.79 MPa flexural
adhesion strength for bone, 4.7 times that without nHAP, and significantly
surpassed commercial cyanoacrylate (0.64 MPa). O-BDSG exhibited degradability
with 51% mass loss after 6 months of implantation. In vivo critical defect and tibia fracture models demonstrated the promoted
osteogenesis of the O-BDSG, with a regenerated bone volume of 75%
and mechanical function restoration to 94% of the native tibia after
8 weeks. The glue can be flexibly adapted to clinical scenarios with
a curing time window of about 3 min. This work shows promising prospects
for clinical application in orthopedic surgery and may inspire the
design and development of bone adhesives
Media 2: Label-free imaging of zebrafish larvae in vivo by photoacoustic microscopy
Originally published in Biomedical Optics Express on 01 February 2012 (boe-3-2-360
Media 1: Label-free imaging of zebrafish larvae in vivo by photoacoustic microscopy
Originally published in Biomedical Optics Express on 01 February 2012 (boe-3-2-360
RGDC Functionalized Titanium Dioxide Nanoparticles Induce Less Damage to Plasmid DNA but Higher Cytotoxicity to HeLa Cells
In this paper, nano-TiO<sub>2</sub> was functionalized
by different methods, and its genotoxicity and cytotoxicity were studied
in detail. The genotoxicity of nano-TiO<sub>2</sub> was evaluated
by observing its interactions with pUC19 plasmid DNA at a single molecule
level using atomic force microscopy. The results show that with the
assistance of UVA radiation, RGDC functionalized nano-TiO<sub>2</sub> induced less damage to plasmid DNA than unmodified ones. The HeLa
cell-specific PDT effect was investigated by cytotoxicity assay correspondingly.
RGDC-functionalized nano-TiO<sub>2</sub> shows the highest killing
effect to HeLa cells with the assistance of UVA radiation. The reasons
that cause the contradiction between genotoxicity and cytotoxicity
were analyzed, and the molecular mechanisms of the PDT effects were
discussed. The results show that the genotoxicity of nano-TiO<sub>2</sub> to plasmid DNA and its cytotoxicity to HeLa cells are related
but also different. The RGDC functionalization is an effective method
to increase the cytotoxicity of nano-TiO<sub>2</sub>
Synergistic Effects of the Ni<sub>3</sub>B Cocatalyst and N Vacancy on gāC<sub>3</sub>N<sub>4</sub> for Effectively Enhanced Photocatalytic N<sub>2</sub> Fixation
The photocatalytic fixation of N2 is a promising technology
for sustainable production of ammonia, while the unsatisfactory efficiency
resulting from the low electron-transfer rate, narrow light absorption
range, and limited active sites of the photocatalyst seriously hinder
its application. Herein, we designed a noble metal-free Schottky junction
photocatalyst constructed by g-C3N4 nanosheets
with N vacancies (VN-CN) and metallic Ni3B nanoparticles
(Ni3B/VN-CN) for N2 reduction to
ammonia. The ammonia yield rate over the optimized Ni3B/VN-CN is 7.68 mM gā1 hā1, which is 6.7 times higher than that of pristine CN (1.15 mM gā1 hā1). The superior photocatalytic
N2 fixation performance of Ni3B/VN-CN can be attributed not only to the formation of Schottky junctions
between Ni3B and VN-CN, which facilitates the
migration and separation of photogenerated electrons, but also to
the incorporation of VN into g-C3N4, which enhances visible light absorption and improves electrical
conductivity. More importantly, Ni3B nanoparticles can
act as the cocatalyst, which provide more active sites for the adsorption
and activation of N2, thereby improving the N2 reduction activity. This work provides an effective strategy of
designing noble metal-free-based cocatalyst photocatalyst for sustainable
and economic N2 fixation
SDS-PAGE (A) and Western blotting (B) analysis of HMW-GSs from <i>Ag. intermedium</i> and bacterial expression products.
<p>Lane 1 is HMW-GSs from common wheat variety Chinese Spring, the four expressed HMW-GSs are noted on left; Lane 2 is native HMW-GS from the seed of <i>Ag. intermedium</i> same as the lane 2 in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0087477#pone-0087477-g001" target="_blank">Figure 1</a>, the seven expressed HMW-GSs are marked with triangles; Lane 3, 5, 7, 9, 11, 13 and 15 are total cell proteins from IPTG induced <i>E. coli</i> containing pET-<i>Glu-1Ai1</i>, pET-<i>Glu-1Ai2</i>, pET-<i>Glu-1Ai3</i>, pET-<i>Glu-1Ai4</i>, pET-<i>Glu-1Ai5</i> pET-<i>Glu-1Ai6</i> and pET-<i>Glu-1Ai7</i>, respectively, whereas the dextral lanes for each of them shows the total cell proteins from their bacterial cells without induction of IPTG. The seven expressed target proteins in <i>E. coli</i>, which were detected by SDS-PAGE (marked with arrows in A) and were confirmed by Western blotting (lanes 3, 5, 7, 9, 11, 13 and 15 in B), share comparable electrophoretic mobility with those native HMW-GSs from <i>Ag. intermedium</i> (lane 2).</p
Systematic Characterization of the Metabolism of Acetoin and Its Derivative Ligustrazine in Bacillus subtilis under Micro-Oxygen Conditions
Bacillus subtilis is an important
microorganism for brewing of Chinese Baijiu, which contributes to
the formation of flavor chemicals including acetoin and its derivative
ligustrazine. The first stage of Baijiu brewing process is under micro-oxygen
conditions; however, there are few studies about B.
subtilis metabolism under these conditions. Effects
of various factors on acetoin and ligustrazine metabolism were investigated
under these conditions, including key genes and fermentation conditions.
Mutation of <i>bdhA</i> (encoding acetoin reductase) or
overexpression of <i>glcU</i> (encoding glucose uptake protein)
increased acetoin concentration. Addition of Vigna
angularis powder to the culture medium also promoted
acetoin production. Optimal culture conditions for ligustrazine synthesis
were pH 6.0 and 42 Ā°C. Ammonium phosphate was shown to promote
ligustrazine synthesis in situ. This is the first report of acetoin
and ligustrazine metabolism in B. subtilis under micro-oxygen conditions, which will ultimately promote the
application of B. subtilis for maintaining
Baijiu quality
MALDI-TOF-MS analysis of peptide mass fingerprint of native 1Aiy1 subunit.
<p>Peptide mass is available at <a href="http://www.expasy.org/tools/peptide-mass.html" target="_blank">http://www.expasy.org/tools/peptide-mass.html</a>.</p
SDS-PAGE (A) and Western blotting (B) analysis of HMW-GSs of <i>Ag. intermedium</i>.
<p>Lane 1 shows the named HMW-GSs from common wheat variety Chinese Spring as a control. Lanes 2ā¼7 show the HMW-GSs from six representative seeds of the <i>Ag. intermedium</i> line used in this study. The seven expressed HMW-GSs with distinct electrophoretic mobility comparing with Chinese Spring were detected by SDS-PAGE (A) and were confirmed using Western blotting experiment with polyclonal antibody specific for HMW-GSs (B). Among the seven HMW-GSs from <i>Ag. intermedium</i>, three subunits (marked with solid triangles in lane 2 of B) share comparable electrophoretic mobility with Chinese Spring, the other four subunits (marked with hollow triangles in lane 2 of B) moved faster than those HMW-GSs from Chinese Spring.</p