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A stable mesoporous multilamellar silica vesicle (MSV) was developed with a gallery pore size of about 14.0 nm. A simulative enzyme, hemoglobin (Hb), was immobilized on this newly developed MSV and a conventional mesoporous silica material SBA-15. The structures and the immobilization of Hb on the mesoporous supports were characterized with x-ray diffraction, transmission electron microscopy, N2 adsorption-desorption isotherms, Fourier transform infrared, ultraviolet-visible spectroscopy, and so forth. MSV is a promising support for immobilizing Hb due to its large pore size and high Hb immobilization capacity (up to 522 mg/g) compared to SBA-15 (236 mg/g). Less than 5% Hb was leached from Hb/MSV at pH 6.0. The activity study indicated that the immobilized Hb retained most peroxidase activity compared to free Hb. Thermal stability of the immobilized Hb was improved by the proctetive environment of MSV and SBA-15. Such an Hb-mesoporous support with high Hb immobilization capacity, high activity, and enhanced thermal stability will be attractive for practical applications. [ABSTRACT FROM AUTHOR]

The TiO2-hollow spheres with uniform shell and diameter have been synthesized using carbon sphere as template, which has abundant -OH groups in its surface hydrophilic layer, and the titanium source was modified into this layer by the covalent -O-Ti bonding. [ABSTRACT FROM AUTHOR]

A high surface area ruthenium dioxide with partial ordered structure has been replicated by cubic Ia3d mesoporous silica, and the replica shows high catalytic activity for the oxidation of CO to CO2 at relatively low temperature. [ABSTRACT FROM AUTHOR]

The present research aims to explore the potential impact of mobile phone radiation on bone marrow haematopoietic stem cell in mice. 160 male BALB/C mice aged 3–4 weeks were randomly distributed into 4 groups as blank control, control, TD-SCDMA and LTE-Advanced respectively, with 40 mice in each group. Mice were designed to receive cell phone radiation for 2–8 weeks. 10 mice in each group were taken out for examinations given radiation exposure periods were 2, 4, 6 and 8 weeks respectively. Then terminal deoxynuclotidyl transferase-mediated dUTP Nick-end labelling technique was conducted to detect the apoptosis of stem cell, and morphological method was carried out for the examination of micronucleus and subpopulations of bone marrow haematopoietic stem cell, while enzyme immune technique was performed to analyse the subsets of T lymphocyte. As a result, no statistical differences were discovered on issues of apoptosis and micronucleus during the entire experimental period in the 2 sham radiation control groups. Notwithstanding similar results were seen in TD-SCDMA and LTE-Advanced groups after exposed to radiation for 2 or 4 weeks, apoptosis began to be enhanced and micronucleus to be increased given the mice experience longer exposure as 6 or 8 weeks. There were virtually negligible effects on subpopulations of stem cell, as well as on subsets of T lymphocyte of peripheral blood during the entire experimental period in the 4 groups. It could be concluded that long-term radiation from cell phone could induce apoptosis of haematopoietic stem cell in mice; moreover, it seems to stimulate the formation of micronucleus, yet with even negligible effect on the proportions of stem cell subpopulations and peripheral blood T lymphocyte subsets. [ABSTRACT FROM AUTHOR]

Presents an amplified fragment length polymorphism (AFLP) genetic linkage map of the silkworm. Average polymorphic AFLP markers generated by each primer combinations; Total length of the AFLP linkage map; Linkage group where sex-linked gene was located.

Mesoporous bioactive glass nanospheres (SiO 2 -CaO-P 2 O 5 , MBG) with remarkable mono-dispersity were successfully synthesized using Pluronic P123 and cetyltrimethylammonium bromide (CTAB) mixed surfactants under neutral condition. The characterizations revealed that MBG NPs had uniform spherical morphology with a homogeneous diameter around 100 nm and mesopores sized at 3.7 nm. The synthesized nanospheres also have excellent bone-like apatite formation ability and much faster degradation rate compared to pure silica nanoparticles. In addition, MBG NPs showed drug storage/release property demonstrated for dexamethasone drug. [ABSTRACT FROM AUTHOR]

The magnetic Fe-MBG/C composite scaffolds with enhanced mechanical strength and multifunctionality have been successfully prepared. The study showed that the Fe-MBG/C composite scaffolds with the porosity of ca. 80% had interconnected macropores (200-500 µm) and mesopores (3.7-4.4 nm) and significantly enhanced the compressive strength compared to the pure MBG scaffolds. Importantly, the Fe-MBG/C composite scaffolds exhibited good bioactivity and sustained drug release property. At the same time, the Fe-MBG/C composite scaffolds could generate heat to raise the temperature of surrounding environment in an alternating magnetic field due to their superparamagnetic behavior. Therefore, the magnetic Fe-MBG/C composite scaffolds could form a multifunctional platform with bone regeneration, magnetic hyperthermia, and local drug delivery and have more potential for use in the regeneration of the critical-sized bone defects caused by bone tumors. [ABSTRACT FROM AUTHOR]

We have prepared multifunctional magnetic mesoporous Fe–CaSiO3 materials using triblock copolymer (P123) as a structure-directing agent. The effects of Fe substitution on the mesoporous structure, in vitro bioactivity, magnetic heating ability and drug delivery property of mesoporous CaSiO3 materials were investigated. Mesoporous Fe–CaSiO3 materials had similar mesoporous channels (5–6 nm) with different Fe substitution. When 5 and 10% Fe were substituted for Ca in mesoporous CaSiO3 materials, mesoporous Fe–CaSiO3 materials still showed good apatite-formation ability and had no cytotoxic effect on osteoblast-like MC3T3-E1 cells evaluated by the elution cell culture assay. On the other hand, mesoporous Fe–CaSiO3 materials could generate heat to raise the temperature of the surrounding environment in an alternating magnetic field due to their superparamagnetic property. When we use gentamicin (GS) as a model drug, mesoporous Fe–CaSiO3 materials release GS in a sustained manner. Therefore, magnetic mesoporous Fe–CaSiO3 materials would be a promising multifunctional platform with bone regeneration, local drug delivery and magnetic hyperthermia.

We have developed composite hydrogels of chitosan (CS) and mesoporous silica nanoparticles (MSNs) in this study. The gelation rate, gel strength, drug delivery behavior and chondrocyte proliferation properties were investigated. The introduction of MSNs into CS accelerated the gelation process at body temperature and also increased the elastic modulus G' from 1000 to 1800 Pa. When we used gentamicin (GS) and bovine serum albumin (BSA) as model small chemical drugs and biomacromolecules, respectively, the CS/MSN hydrogels released GS and BSA in a sustained manner simultaneously, but the CS hydrogels only showed sustained BSA release. Furthermore, in vitro chondrocyte culture showed that the CS/MSN composite hydrogels indeed performed much better in supporting chondrocyte growth and maintaining chondrocytic phenotype compared to the CS hydrogels. Therefore, the results suggest that the CS/MSN composite hydrogels can be potentially very useful for cartilage regeneration.

Deep brain stimulation (DBS) has been used as a treatment of brain diseases such as Parkinson's disease and is a promising therapy for epilepsy. But the mechanisms of high frequency stimulation (HFS) used by DBS are still uncertain. In order to investigate the changes of action penitential firings of individual neurons (single unit activity, SUA) during the period of HFS, a new algorithm based on window detection was designed to detect spikes in broadband-frequency recording signals. The results show that orthodromic-HFS (O-HFS) could excite the neurons in CA1 regions, and the firing rate of interneurons and pyramidal neurons increased significantly. In particular, a decrease in spike amplitude for both interneurons and pyramidal neurons was observed during the period of O-HFS. The amplitude decrease of unit spikes was most remarkable with the presence of HFS-induced population spike (PS). These results suggest that the stimulation pulses of O-HFS could activate the downstream neurons continuously, leading to the downstream neurons being unable to repolarize completely. The results are important for tracking individual neuron activity during HFS and for further understanding of DBS mechanisms.