Thrombospondin-4 (TSP4) gene-modified bone marrow stromal cells (BMSCs) promote the effect of therapeutic angiogenesis in critical limb ischemia (CLI) of diabetic rats.

Critical limb ischemia (CLI) is the leading cause of lower limb amputation. Traditional treatments for CLI have limitations. Studies have shown that thrombospondin-4 (TSP4) can promote the growth of neovascularization. In this study, we observed the angiogenesis efficiency of TSP4-overexpressing BMSC transplantation in CLI treatment. The recombinant FT106-tsp4-gfp lentiviral vector plasmid was constructed and transfected into 293FT cells. Primary BMSCs were successfully infected with the tsp4 virus, and TSP4 overexpression was confirmed before TSP4-BMSCs infusion. A rat CLI model was established, and 60 CLI rats were randomly divided into the CLI, BMSC + CLI and TSP4-BMSC + CLI groups. The effect of TSP4-BMSC on angiogenesis was detected by the motor function, immunohistochemistry and immunofluorescence staining assays. Neovascular density was detected by digital subtraction angiography (DSA). Our results demonstrated that TSP4-BMSCs improved the motor function score of the CLI rats and increased MMP2, MMP9, Ang-1, VEGF and vWF protein expression in tissue of the ischaemic area. Meanwhile, new blood vessels can be observed around the ischemic area after TSP4-BMSCs treatment. Our data illustrate that TSP4-BMSCs can promote the recovery of motor function in diabetic hind limb ischaemic rats. TSP4-BMSCs have better therapeutic effects than BMSCs.

Promoting therapeutic angiogenesis of focal cerebral ischemia using thrombospondin-4 (TSP4) gene-modified bone marrow stromal cells (BMSCs) in a rat model.

BACKGROUND: A stroke caused by angiostenosis always has a poor prognosis. Bone marrow stromal cells (BMSC) are widely applied in vascular regeneration. Recently, thrombospondin-4 (TSP4) was reported to promote the regeneration of blood vessels and enhance the function of endothelial cells in angiogenesis. In this work, we observed the therapeutic effect of TSP4-overexpressing BMSCs on angiogenesis post-stroke. METHODS: We subcloned the tsp4 gene into a lentivirus expression vector system and harvested the tsp4 lentivirus using 293FT cells. Primary BMSCs were then successfully infected by the tsp4 virus, and overexpression of GFP-fused TSP4 was confirmed by both western blot and immunofluorescence. In vitro, TSP4-overexpressing BMSCs and wild-type BMSCs were co-cultured with human umbilical vein endothelial cells (HUVECs). The expression level of TSP4, vascular endothelial growth factor (VEGF) and transforming growth factor-ß (TGF-ß) in the supernatant were detected by enzyme-linked immunosorbent assay (ELISA). Wound healing, tube formation and an arterial ring test were performed to estimate the ability of TSP4-overexpressing BMSCs to promote the angiogenesis of endothelial cells. Using a rat permanent middle cerebral artery occlusion (MCAO) model, the effect of TSP4-overexpressing BMSCs on the regeneration of blood vessels was systematically tested by the neurological function score, immunohistochemistry and immunofluorescence staining assays. RESULTS: Our results demonstrated that TSP4-overexpressing BMSCs largely increased the expression of VEGF, angiopoietin-1 (Ang-1), matrix metalloprotein 9 (MMP9), matrix metalloprotein 2 (MMP2) and p-Cdc42/Rac1 in endothelial cells. TSP4-BMSC treatment notably up-regulated the TGF-ß/Smad2/3 signalling pathway in HUVECs. In vivo, the TSP4-BMSC infusion improved the neurological function score of MCAO rats and expanded the expression of the von Willebrand factor (vWF), Ang-1, MMP2 and MMP9 proteins in cerebral ischemic penumbra. CONCLUSIONS: Our data illustrate that TSP4-BMSCs can promote the proliferation and migration of endothelial cells and tube formation. We found that TSP4-BMSC infusion can promote the recovery of neural function post-stroke. The tsp4 gene-modified BMSCs provides a better therapeutic effect than that of wild-type BMSCs.

Zn2SnO4-Reduced Graphene Oxide Nanohybrids for Visible-Light-Driven Photocatalysis.

Zn2SnO4-reduced graphene oxide photocatalysts were synthesized by using SnCl4 5H2O, Zn(NO3)2 · 6H2O and graphene oxide via hydrothermal process. The structure, morphology, specific surface area and photo response of the as-prepared nanocomposites were characterized by X-ray diffraction, Transmission electron microscopy, UV-vis diffuse reflectance spectra, Brunauer-emmett-teller surface area measurement and Photoluminescence emission spectra. Experimental results showed that the Zn2SnO4 nanoparticles, with 20-30 nm a size range, were uniformly dispersed on the surfaces of reduced graphene oxide. Moreover, the as-prepared Zn2SnO4-reduced graphene oxide photocatalysts exhibited enhanced photocatalytic activities for degradation of Rhodamine B compared to those of pure Zn2SnO4. When the amount of reduced graphene oxide was 4 wt%, it showed the highest photocatalytic efficiency of 99.7% for 240 min, and the photocatalytic efficiency was still 98.5% after it was recycled 4 times. It also possessed the band gap of 2.48 eV and specific surface area of 58.1 m2 g-1.

Preparation and Characterization of Nanosized Bi-Doped SnO2/Reduced Graphene Oxide 3D Hybrids for Visible-Light-Driven Photocatalysis.

The nanosized Bi-doped SnO2/reduced graphene oxide 3D hybrids have been synthesized via one-step hydrothermal method. The structures, morphologies, photocatalytic activities of the as-prepared samples were discussed, respectively. The formation mechanism of the as-prepared hybrids was also proposed. Experimental results indicated that the usage amount of Bi2Sn2O7 obviously affected the photocatalytic performance of the as-prepared products. When it was 450 mg, the as-prepared sample possessed the band gap energy of 1.9 eV and the photocatalytic efficiency of 90% in 210 min for degradation of rhodamine B solution. In addition, triethylene tetramine and the as-prepared carbon hydrogel could act as reductant to synergistically reduce Bi2Sn2O7 into Bi-doped SnO2 particles during the formation of the hybrids.

Solvothermal Preparation of Zinc Oxide/Reduced Graphene Oxide Composites for Rapid Removal of Methylene Blue.

Zinc oxide/reduced graphene oxide composites with various morphologies and properties were prepared via a one-step solvothermal process. The formation of zinc oxide and reduction of graphene oxide were simultaneously accomplished. These as-obtained samples showed high performance in removing methylene blue from aqueous solution. Solvent could play an important role in tuning the morphologies of the zinc oxide and the efficiency of the final composites. Composites prepared in acetone showed the highest removal efficiency, compared with those prepared in water and ethanol. Loading content of the reduced graphene oxide could affect the performance as well. With the increase in the content of the reduced graphene oxide, the as-prepared samples showed enhanced performance gradually. The as-prepared composite showed certain stability, with a maximum recyclability of 5 times for efficient removal. The effective removal of target dye turned out to be the result of the combination of physical adsorption and photo-catalysis.

Solvent-Mediated Preparation of Zinc Ferrite-Reduced Graphene Oxide Nanocomposites and Its Application in Removal of Methylene Blue.

Zinc ferrite-reduced graphene oxide composites, which could effectively remove the methylene blue from aqueous solution, were prepared via a facile solvothermal process. These as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, vibration sample magnetometer and UV-vis diffuse reflectance spectroscopy. Experimental results showed that solvents played an important role in the electron structure of the final samples. Moreover, they influenced the photocatalytic performance as well. Among all the samples prepared in different solvents, those composites prepared in N-N-dimethylformamide showed the greatest performance. They could effectively remove more than 90% of the methylene blue from the solution in about 180 min. The efficient removal of target dye turned out to be the result of the combination of physical adsorption and photocatalytic degradation under visible light irritation. These catalysts showed remarkable stability, which could be effectively reused for three times. In addition, all these samples showed a certain magnetic response, which was beneficial to recycle.

Preparation of Reduced-Graphene Nanoribbons via One-Step Solvothermal Process.

Carbon nanotubes were unzipped to become reduced-graphene nanoribbons via one-step solvothermal process in a Teflon-lined autoclave. The samples were characterized by X-ray diffraction, thermo-gravimetric analysis and transmission electrical microscopy, respectively. Results showed that the solvothermal reaction temperature played an important role in the structure of the samples. When it was 75 °C, carbon nanotubes were completely cutted into graphene oxide nanoribbons. Moreover, when it was 155 °C, they were become reduced-graphene nanoribbons. Furthermore, the as-prepared reduced-graphene nanoribbons could improve mechanical strength of the phenolic resin/hollow glass beads foamed composites. When the reduced-graphene nanoribbons loading was 0.4 wt%, the tensile and compressive strength of the composites were increased by 19.7% and 21.3%, respectively.

Super-tough and self-healable all-cellulose-based electrolyte for fast degradable quasi-solid-state supercapacitor.

Recyclable and degradable supercapacitors have promising applications for a sustainable energy storage industry. Herein, we prepare a dual-physical crosslinking (DP) carboxymethyl cellulose (CMC) hydrogel with high-toughness, healability, and electric conductivity by integrating abundant ions into the matrix. The prepared hydrogel displays a maximum compressive fracture stress of 4.42 MPa, fast healing in five seconds, and full degradation within eight days. Moreover, the fabricated supercapacitor shows high specific capacitance (309 F g-1) and volumetric capacitance (2.60 F cm-3). The supercapacitor achieves a healing efficiency of 93.9 % after five cuttings, and exhibits a cycling stability of 84.6 % capacitance retention after 1000 cycles. These merits ensure that the all-cellulose-based supercapacitor can operate in case of sudden collision and deformation, which contribute to reducing the environmental hazards from supercapacitor's preparation to its abandonment.

A Lead-Free 0D/2D Cs3Bi2Br9/Bi2WO6 S-Scheme Heterojunction for Efficient Photoreduction of CO2.

Photocatalytic reduction of CO2 into valuable hydrocarbon fuels is one of the green ways to solve the energy problem and achieve carbon neutrality. Exploring photocatalyst with low toxicity and high-efficiency is the key to realize it. Here we report a lead-free halide perovskite-based 0D/2D Cs3Bi2Br9/Bi2WO6 (CBB/BWO) S-scheme heterojunction for CO2 photoreduction, prepared by a facile electrostatic self-assembly approach. The CBB/BWO shows superior photoreduction of CO2 under visible light with CO generation rate of 220.1 µmol·g-1·h-1, which is ∼115.8 and ∼18.5 times higher than that of Cs3Bi2Br9 perovskite quantum dots (CBB PQDS) and Bi2WO6 nanosheets (BWO NS), respectively. The improved photocatalytic activity can be attributed to the tight 0D/2D structure and S-scheme charge transfer pathway between the Cs3Bi2Br9 PQDS and atomic layers of the Bi2WO6 NS, which shortens transmission distance of photogenerated carriers and boosts efficient separation and transfer of the carriers. This work provides insight in manufacturing potential lead-free perovskite-based photocatalysts for achieving carbon neutrality.

Synthesis, characterization and photocatalytic properties of In2.77S4/Ti3C2 composites.

Recently, the problem of water pollution, caused by antibiotics, is becoming more and more serious. Photocatalysis is one of the promising technologies for removing antibiotics from water. Herein, the In2.77S4/Ti3C2 composites were prepared by an in-situ hydrothermal growth method for photocatalytic degradation of tetracycline (TC). The as-developed composites were characterized by various methods. The UV-Vis DRS spectra reveals that the introduction of Ti3C2 makes the bandgap of the as-prepared composites smaller and the visible light absorption ability improved. The photocatalytic degradation efficiency of the as-prepared composite is enhanced under visible light illumination. It is shown as first increasing and then decreasing with increasing the content of Ti3C2 in the composite and reaches to the maximum of 89.3% in 90 min, which is higher than 75.1% of In2.77S4 and 6.7% of Ti3C2. The reason of improvement is the interface between In2.77S4 and Ti3C2 is tightly combined to form a heterojunction. Moreover, the photocurrent intensity of the as-obtained composite is improved, while its Nyquist arc radius is decreased. In addition, holes are the main active species and ·OH and ·O2 - play an auxiliary role during the degradation of TC.

[Effect of chronic psychological stress on vascular endothelial dysfunction rats and intervention tongxinluo on it].

OBJECTIVE: To observe the effect of chronic psychological stress on vascular endothelial dysfunction rats and to explore the intervention and mechanism of Tongxinluo (TXL) on it. METHODS: Forty male Wistar rats were randomly divided into the normal control group (with no modeling), the endothelial dysfunction group (the HCY group), the psychological stress group (the model group), and TXL group, ten in each group. Rats in the latter three groups were fed with 3% high methionine diet to duplicate vascular endothelial dysfunction (VED) model. In addition, chronic psychological stress was applied in VED rats using repeated binding method. TXL at the dose of 1.2 g/kg body weight was given by gastrogavage. The plasma endothelin (ET) and angiotensin II (Ang II), serum cortisone (CORT) were detected by radioimmunoassay. The serum nitric oxide (NO) was detected by nitrate reductase. Ultrastructural changes of aortic endothelial cells were observed by transmission electron microscope. Serum levels of norepinephrine (NE) and epinephrine (E) were detected by enzyme linked immunosorbent assay (ELISA). RESULTS: Compared with the plasma ET level and the serum NO level in the HCY group (161.70 +/- 13.96 pg/mL and 26.82 +/- 13.03 micromol/L), the plasma ET level obviously increased (178.25 +/- 21.85 pg/mL) (P < 0.05) and the serum NO level decreased (24.91 +/- 9.95 micromol/L, P > 0.05), levels of CORT, NE, and E obviously increased in the model group (all P < 0.05). Ultrastructural changes of aortic endothelial cells were obviously injured. Compared with the model group, the plasma ET level (154.74 +/- 13.27 pg/mL), Ang II, CORT, NE, and E obviously decreased (P < 0.05, P < 0.01), the serum NO level obviously increased (34.44 +/- 18.35 micromol/L, P < 0.05). Ultrastructural changes of aortic endothelial cells were obviously improved. CONCLUSIONS: Chronic psychological stress could obviously aggravate endothelial injury in VED rats. TXL showed protection on the vascular endothelial structure and function.

Effect of Cu2+ on Corrosion Behavior of A106B Carbon Steel and 304L Stainless Steels in Seawater.

The corrosion behaviors of A106B carbon steel and 304L stainless steel (SS) in seawater with different Cu2+ concentrations were studied by the immersion test and the potentiodynamic polarization test. The results showed that with the increasing Cu2+ concentration, the mass lot rates of A106B and 304L SS all increased in the immersion test, and compared with A106B, the mass lot rates of 304L SS were all smaller. In the potentiodynamic polarization test, following the concentration of Cu2+ increased, the corrosion potential of A106B firstly shifted negatively; then, when Cu2+ increased to 100 ppm, the polarization curve moved to the upper right direction; namely, both the corrosion potential and corrosion electrical density increased. The corrosion potential of 304L SS increased with the increasing Cu2+, and the passive region was reduced; the pitting sensitivity improved.

[Effects of Tongxinluo on repeated hypoxic tolerance in mice].

OBJECTIVE: To observe the effects of Tongxinluo (TXL) on repeated hypoxic tolerance in mice and explore the underlying mechanisms. METHODS: Mice were randomly divided into groups of repeated hypoxia (control) and TXL according to body weights. The mice in each group were exposed to acute repeated hypoxia for 0 run (H0), 1 run (H1), 3 runs (H3) and 5 runs (H5). The animal's tolerance time of each hypoxic exposure was recorded. Western blot was used to measure the protein levels of hypoxia inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) in cortex tissue. RESULTS: The hypoxic tolerance time in control and TXL groups significantly increased run by run. Both HIF-1alpha and VEGF proteins in two groups increased gradually. Compared with control group, the tolerance time in H1 of TXL group [(18.0 +/- 2.4) minvs (15.6 +/- 2.0) min], H3 [(68.3 +/- 13.2) min vs (41.7 +/- 9.0) min) and H5 (85.9 +/- 7.0) min vs (51.4 +/- 14.4) min] increased (P < 0.05 or P < 0.01); the HIF-1alpha protein expression in H1 of TXL group (0.95 +/- 0.04 vs 0.79 +/- 0.02), H3 (1.01 +/- 0.03 vs 0.85 +/- 0.02), H5 (1.16 +/- 0.02 vs 0.92 +/- 0.03) increased (P < 0.05 or P < 0.01); the VEGF protein expression in H3 of TXL group (1.14 +/- 0.02 vs 0.89 +/- 0.03), H5 (1.34 +/- 0.05 vs 0.99 +/- 0.07) increased (P < 0.05 or P < 0.01). CONCLUSIONS: Under repeated hypoxia, an organism has a strong adaptive ability. The rises of HIF-1alpha and VEGF may be an adaptive mechanism. TXL can increase obviously the adaptive ability of mice to hypoxia.

AgBrO3/Few-Layer g-C3N4 Composites: A Visible-Light-Driven Photocatalyst for Tetracycline Degradation.

The AgBrO3/few-layer g-C3N4 composite photocatalyst has been developed via an in-situ synthetic method. The structure, morphology, light response range, separation and migration efficiency of the photogenerated electron-hole pairs and element valence state of the as-obtained samples have been characterized. The tetracycline was used to discuss the photocatalytic activities of the samples. The photocatalytic degradation mechanism of the as-obtained composites was also researched. The analysis results show that the photocatalytic degradation property of the asobtained composite photocatalyst appears to the tendency of first increasing and then decreasing with increasing the amount of AgBrO3 under visible light illumination. When the mass ratio of AgBrO3 to g-C3N4 is 4:3, in 60 min, the photocatalytic degradation efficiency of the as-obtained composites reaches the maximum of 79%. It is 37% and 45% higher than that of pure AgBrO3 and g-C3N4, respectively. Moreover, the separation and migration efficiency of the photogenerated electron-hole pairs of the as-prepared composites are also enhanced. In addition, superoxide radicals and holes are the dominant active species during the photocatalytic degradation process.

Effects of Chinese herbs on multiple ion channels in isolated ventricular myocytes.

BACKGROUND: Shensong Yangxin (SSYX) is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current (I(Na)), L-type calcium current (I(Ca, L)), transient outward potassium current (I(to)), delayed rectifier current (I(K)), and inward rectifier potassium currents (I(K1)) in isolated ventricular myocytes. METHODS: Whole cell patch-clamp technique was used to study ion channel currents in enzymatically isolated guinea pig or rat ventricular myocytes. RESULTS: SSYX decreased peak I(Na) by (44.84 +/- 7.65)% from 27.21 +/- 5.35 to 14.88 +/- 2.75 pA/pF (n = 5, P < 0.05). The medicine significantly inhibited the I(Ca, L). At concentrations of 0.25, 0.50, and 1.00 g/100 ml, the peak I(Ca, L) was reduced by (19.22 +/- 1.10)%, (44.82 +/- 6.50)% and (50.69 +/- 5.64)%, respectively (n = 5, all P < 0.05). SSYX lifted the I - V curve of both I(Na) and I(Ca, L) without changing the threshold, peak and reversal potentials. At the concentration of 0.5%, the drug blocked the transient component of I(to) by 50.60% at membrane voltage of 60 mV and negatively shifted the inactive curve and delayed the recovery from channel inactivation. The tail current density of I(K) was decreased by (30.77 +/- 1.11)% (n = 5, P < 0.05) at membrane voltage of 50 mV after exposure to the medicine and the time-dependent activity of I(K) was also inhibited. Similar to the effect on I(K), the SSYX inhibited I(K1) by 33.10% at the test potential of -100 mV with little effect on reversal potential and the rectification property. CONCLUSIONS: The experiments revealed that SSYX could block multiple ion channels such as I(Na) I(Ca, L), I(k), I(to) and I(K1), which may change the action potential duration and contribute to some of its antiarrhythmic effects.

[Remote postconditioning by brief renal ischemia and reperfusion reduces acute myocardial ischemia and reperfusion induced myocardial apoptosis in rabbits].

OBJECTIVES: To observe the effects of renal ischemic postconditioning (RI-Post) on myocardial apoptosis in rabbits with acute myocardial ischemia and reperfusion. METHODS: All rabbits were subjected to 60 minutes ischemia by left anterior descending coronary artery occlusion (LADO) and 6 hours reperfusion. The rabbits are randomly divided into 3 groups (n = 8 in each group): (1) Ischemia-reperfusion (IR): LADO and reperfusion without additional intervention; (2) RI-Post: after 60 minutes of LADO, the left renal artery was occluded for 30 seconds and reperfused for 30 seconds and repeated 3 times, then the coronary artery was reperfused for 6 hours; (3) Medication intervention (MI): 10 minutes before coronary reperfusion, rabbits were treated with PKC antagonist GF109203X (0.05 mg/kg, IV), followed by RI-Post treatment and 6 hours coronary reperfusion. Myocardial apoptosis was measured by TUNEL and the myocardial Bcl-2 and Bax protein expressions were assessed by immunohistochemistry. RESULTS: Compared with the IR group and the MI group, myocardial apoptosis was significantly reduced (P < 0.05) and the Bcl-2 protein expression increased (P < 0.01) while the Bax protein expression decreased (P < 0.05) in the RI-Post group. CONCLUSIONS: Remote renal postconditioning applied right before the onset of coronary artery reperfusion can reduce the myocardial apoptosis induced by myocardial ischemia and reperfusion and up-regulate Bcl-2 while down-regulate Bax expression possibly by activation of protein kinase C.

Vaccination of adults 65 years of age and older with tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine (Boostrix(®)): results of two randomized trials.

BACKGROUND: Pertussis can cause significant morbidity in elderly patients, who can also transmit this disease to infants and young children. There is little data available on the use of acellular pertussis vaccines in recipients ≥65 years of age. METHODS: Two studies examined the safety and immunogenicity of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccine (Boostrix(®)) in healthy ≥65 year olds. In Study A subjects received single doses of Tdap and seasonal influenza vaccine either co-administered or given one month apart. In Study B subjects received either Tdap or tetanus-diphtheria (Td) vaccine. Antibodies were measured before and one month after vaccination. Reactogenicity and safety were actively assessed using diary cards. RESULTS: A total of 1104 subjects 65 years of age and older received a Tdap vaccination in the two studies. In study A, no differences in immune responses to Tdap or influenza vaccine were observed between co-administered or sequentially administered vaccines. In study B, Tdap was non-inferior to Td with respect to diphtheria and tetanus seroprotection, and anti-pertussis GMCs were non-inferior to those observed in infants following a 3-dose diphtheria, tetanus and acellular pertussis (DTaP) primary vaccination series, in whom efficacy against pertussis was demonstrated. Reports of adverse events were similar between Tdap and Td groups. CONCLUSIONS: Tdap was found to be immunogenic in subjects ≥65 years, with a safety profile comparable to US-licensed Td vaccine. Tdap and influenza vaccine may be co-administered without compromise of either the reactogenicity or immunogenicity profiles of the two vaccines.

Persistence of antibodies 3 years after booster vaccination of adults with combined acellular pertussis, diphtheria and tetanus toxoids vaccine.

The duration of protection after vaccination with reduced antigen content diphtheria, tetanus and acellular pertussis vaccines (Tdap) is not known. Long-term post-vaccination serological data will help to improve understanding of the duration of humoral immunity and guide vaccination policy for the timing of repeat dose administration. The persistence of antibodies to Tdap antigens was measured 3 years after vaccination of adults 19-64 years of age with one of 2 Tdap vaccines (Boostrix(®), GlaxoSmithKline Biologicals; Tdap-B: or Adacel(®), Sanofi Pasteur; Tdap-A). In both groups, geometric mean concentrations for antibodies to diphtheria, tetanus, and pertussis vaccine antigens were decreased at year 3 relative to levels observed 1 month and 1 year following vaccination, but remained higher than pre-vaccination levels. Seroprotection rates for diphtheria and tetanus remained high for both Tdap vaccines (for diphtheria, 96.9% and 97.8% for the Tdap-B and Tdap-A groups, respectively; for tetanus, 98.1% and 99.6%, respectively).

Evaluation of magnesium ions release, biocorrosion, and hemocompatibility of MAO/PLLA-modified magnesium alloy WE42.

Magnesium alloys may potentially be applied as biodegradable metallic materials in cardiovascular stent. However, the high corrosion rate hinders its clinical application. In this study, a new approach was adopted to control the corrosion rate by fabricating a biocompatible micro-arc oxidation/poly-L-lactic acid (MAO/PLLA) composite coating on the magnesium alloy WE42 substrate and the biocompatibility of the modified samples was investigated. The scanning electronic microscope (SEM) images were used to demonstrate the morphology of the samples before and after being submerged in hanks solution for 4 weeks. The degradation was evaluated through the magnesium ions release rate and electrochemical impedance spectroscopy (EIS) test. The biocompatibility of the samples was demonstrated by coagulation time and hemolysis behavior. The result shows that the poly-L-lactic acid (PLLA) effectively improved the corrosion resistance by sealing the microcracks and microholes on the surface of the MAO coating. The modified samples had good compatibility.

Immunogenicity and reactogenicity of co-administered tetanus-diphtheria-acellular pertussis (Tdap) and tetravalent meningococcal conjugate (MCV4) vaccines compared to their separate administration.

In the United States, co-administration of tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccine and tetravalent meningococcal conjugate vaccine (MCV4) is recommended in adolescents. In this clinical study, 1341 adolescents received Tdap (Boostrix® GlaxoSmithKline) and MCV4 (Menactra®, Sanofi-Pasteur) simultaneously or sequentially one month apart. Co-administration of Tdap+MCV4 was well tolerated and immunogenic, resulting in high levels of antibodies against diphtheria, tetanus, pertussis and meningococcal serogroup A,C,W-135 and Y antigens. The data provide support for current recommendations for co-administration of Tdap and MCV4 vaccines at the same office visit.