OBJECTIVE: To investigate the effects of novel bioactive glasses (BG) including PSC with high phosphorus component and FBG with fluorine-doped element on promoting remineralization of artificial dentin caries. METHODS: (1) BGs were used in this study as follows: PSC (10.8%P₂O₅-54.2%SiO₂-35.0%CaO, mol.%) were synthesized using phytic acid as the phosphorus precursor through sol-gel method. FBG (6.1%P₂O₅-37.0%SiO₂-53.9%CaO-3.0%CaF₂, mol.%) and 45S5(6.0%P₂O₅-45.0%SiO₂-24.5%CaO-24.5%Na₂O, mol.%) were synthesized by traditional melt method. (2) The above BGs were soaked in simulated body fluid (SBF) for 24 hours. Then X-ray diffraction (XRD) was used to analyze the formation of hydroxyapatite (HA) crystals. (3) Prepared 1 mm thick dentin slices were soaked in 17% ethylene diamine tetraacetic acid (EDTA) for 1 week to demineralize the dentin. Then the dentin slices treated by BG were soaked in SBF for 1 week. Field emission scanning electron micro-scopy (FE-SEM) was used to observe the surface morphology of the dentin slices. (4) Four cavities were prepared to 1 mm depth in each 2 mm thick dentin slice, then were treated with lactic acid for 2 weeks to form the artificial dentin caries. Wax, mineral trioxide aggregate (MTA), PSC and FBG were used to fill four cavities as blank control group, MTA group, PSC group and FBG group respectively. Then the spe-cimens were soaked in SBF for 4 weeks. The changes of depth and density of demineralized dentin were analyzed using Micro-CT before filling and after 2 and 4 weeks filling. RESULTS: (1) PSC and FBG promoted mineral formation on the surfaces of the demineralized dentin. And the speed was faster and crystallinity was higher in PSC group than the FBG and 45S5 groups. (2) The increased mineral density of artificial dentin caries in PSC group were (185.98 ± 55.66) mg/cm³ and (213.64 ± 36.01) mg/cm³ 2 and 4 weeks after filling respectively, which were significantly higher than the control group [(20.38 ± 7.55) mg/cm³, P=0.006; (36.46 ± 10.79) mg/cm³, P=0.001]. At meanwhile, PSC group was also higher than MTA group [(57.29 ± 10.09) mg/cm³; (111.02 ± 22.06) mg/cm³], and it had statistical difference (P=0.015; P=0.006). The depth of remineralized dentin in PSC group were (40.0 ± 16.9) μm and (54.5 ± 17.8) μm 2 and 4 weeks respectively, which were also statistically different from the control group (P =0.010;P=0.001). There were no statistical differences between the control group and MTA group. The above effects of FBG group were between PSC and MTA. CONCLUSION PSC has advantages in the speed, quality and depth of mineral deposition in the demineralized layer of artificial dentin caries. It would be expected to be an ideal material to promote the remineralization of dentin caries.
Dentin ; Silicon Dioxide/pharmacology* ; Dental Caries Susceptibility ; Minerals/pharmacology* ; Phosphorus/pharmacology* ; Tooth Remineralization/methods*

1,3,5-Trimethylbenzene (1,3,5-TMB) was used as the pore-enlarging modifier to expand the pore size of MCM-41 (mobil company of matter) mesoporous silica nanoparticles. The solvent impregnation method was adopted to assemble non-water-soluble β-carotene into the pore channel of MCM-41. The MCM-41 and drug assemblies were characterized by TEM, FT-IR, elemental analysis and N2 adsorption-desorption. The results showed that MCM-41 has good sphericity and regular pore structure. The research also investigated the optimal loading time, the drug loading and the vitro stability of the β-carotene. As a drug carrier, the modified MCM-41 showing a shorter drug loading time, the drug loading as high as 85.58% and the stability of β-carotene in drug assemblies has improved. The study of this new formulation provides a new way for β-carotene application.
Drug Carriers ; chemistry ; Drug Delivery Systems ; Drug Stability ; Nanoparticles ; chemistry ; Silicon Dioxide ; chemistry ; beta Carotene ; chemistry ; pharmacology

Currently, chemotherapy is one of the main therapy for cancer. But the traditional antitumor drugs are systemic distribution in vivo, they are difficult to achieve an effective drug concentration in the tumor tissue and don't have the ability to distinguish normal cells and tumor cells by themselves, that cause systemic toxicity easily and can not meet the clinical needs. With the research on mesoporous silica nanoparticles (MSNs) deepening, more and more attention in the drug delivery system have been payed to in recent years, because of its unique physicochemical structure characteristics, it has the effect on specific targets, directly inhibits the tumor cell growth, reduces the side effects to normal cells, tissues and organs and can be long-term medication, etc. It is expected to be excellent carriers of antitumor drugs. MSNs application in the field of cancer treatment has now become a hot research field of medicine. In this paper, the latest research about MSNs in antitumor drugs targeting delivery system from 2008 to 2015 is summarized, including the application of MSNs separately in antitumor drug targeting, passive targeting, active targeting, physical or chemical conditions response targeting and other compound targeting drug delivery system. We expect it to provide a reference to the toxicity reducing and efficacy enhancing and further development of chemical medicine, natural medicine and monomeric compound of chinese herbal medicine.
Animals ; Antineoplastic Agents ; chemistry ; pharmacology ; Drug Delivery Systems ; methods ; trends ; Humans ; Nanoparticles ; chemistry ; Neoplasms ; drug therapy ; Silicon Dioxide ; chemistry

Animals ; Inflammation ; chemically induced ; Lung ; drug effects ; Oligodeoxyribonucleotides ; pharmacology ; Pulmonary Alveoli ; drug effects ; pathology ; Silicon Dioxide ; adverse effects

OBJECTIVETo compare the dissolution characteristics of colloidal silica and porous silica as the solid dispersion carrier, with baicalin as the model drug.

METHODThe baicalin solid dispersion was prepared by the solvent method, with colloidal silica and porous silica as the carriers. In the in vitro dissolution experiment, the solid dispersion was identified by scanning electron microscopy, differential scanning and X-ray diffraction.

RESULTThe solid dispersion carriers prepared with both colloidal silica and porous silica could achieve the purpose of rapid release. Along with the increase in the proportion of the carriers, the dissolution rate is accelerated to more than 80% within 60 min. Baicalin existed in the solid dispersion carriers in the non-crystalline form.

CONCLUSIONThe release behaviors of the baicalin solid dispersion prepared with two types of carrier were different. Among the two solid dispersion carriers, porous silica dissolved slowly than colloidal silica within 60 min, and they showed similar dissolutions after 60 min.

Calorimetry, Differential Scanning ; Colloids ; chemistry ; Drug Carriers ; chemistry ; Drug Delivery Systems ; instrumentation ; Flavonoids ; chemistry ; pharmacology ; Porosity ; Silicon Dioxide ; chemistry ; Solubility

This paper is to prepare curcumin (Cur) loaded mesoporous silica nanoparticle (Cur-MSN), evaluate its release behavior and anti-cancer activity in vitro. Mesoporous silica nanoparticle (MSN) was prepared by polymerization method and Cur-MSN was obtained using solvent evaporation method and impregnation centrifugation method. The preparation method was optimized using entrapment efficiency (EE) and loading efficiency (LE) as indexes. Cur-MSN was characterized with scanning electron microscope and its particle size and zeta potential were determined. Finally, in vitro release behavior in 0.2% SDS solution and its cell-killing effect on HeLa cells were also evaluated. The Cur-MSN prepared with process optimization method was round and uniform and exhibited typical mesoporous characterization. The mean particle size and Zeta potential of Cur-MSN were 75.8 nm and -30.1 mV, respectively. EE and LE of three batches of Cur-MSN were (72.55 ± 2.01)% and (16.21 ± 1.12)%, respectively. In vitro release behavior of Cur-MSN showed a sustained release profile with 83.5% cumulative release within 96 h. The killing effect of Cur-MSN on HeLa cells was dose-dependent with IC50 of 19.40 mg x L(-1), which was similar to that of Cur.
Antineoplastic Agents, Phytogenic ; chemistry ; pharmacology ; Curcumin ; chemistry ; pharmacology ; Drug Carriers ; chemistry ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Humans ; Nanoparticles ; chemistry ; Neoplasms ; drug therapy ; Particle Size ; Porosity ; Silicon Dioxide ; chemistry

Animals ; Bronchoalveolar Lavage Fluid ; chemistry ; Curcumin ; pharmacology ; Glycyrrhizic Acid ; pharmacology ; Lung ; drug effects ; metabolism ; Male ; Rats ; Rats, Wistar ; Silicon Dioxide ; toxicity

OBJECTIVETo detect DNA damage in Chinese Hamster Lung Fibroblast(CHLF) exposed to low doses of silica particles(7.5 - 120.0 micrograms/ml).

METHODSComet assay was used to detect DNA damage. The cells were divided into various groups by doses and incubation time of silica particles to observe silica-induced DNA damage; and the influence of hydroxyl radicals and calcium ion in DNA damage by using deferoxamine and verapamil was also studied. The tail lengths of comet were used to measure DNA damage.

RESULTSThe tail lengths were significantly longer in exposed cells, compared to matched controls(P < 0.01), and were increased in a dose-dependent manner from 7.5-120.0 micrograms/ml. The tail lengths of two-hour group were longer than one-hour group. When exposed to 90 micrograms/ml silica particles, 0.5-2.0 mmol/L deferoxamine and 2.5-20.0 micrograms/ml verapamil could attenuate silica-induced DNA damage effectively, their protective effects were increased in a concentration-dependent manner.

CONCLUSIONSmall dose of SiO2 could induce CHLF DNA damage. Calcium ion and hydroxyl radical may take part in this process, antioxidant and calcium antagonate may protect SiO2 induced DNA damage.

Animals ; Calcium ; physiology ; Comet Assay ; Cricetinae ; Cricetulus ; DNA Damage ; Deferoxamine ; pharmacology ; Dose-Response Relationship, Drug ; Hydroxyl Radical ; Silicon Dioxide ; toxicity ; Verapamil ; pharmacology

OBJECTIVETo characterize the role of Toll-like receptor 4 (TLR4) in silica-induced production of tumor necrosis factor alpha (TNFalpha) from macrophage cell line.

METHODSThe human macrophage cell line THP-1 was incubated with silica suspension. Cell media were collected and TNFalpha levels in the supernatants measured with ELISA. To examine the involvement of TLR4 in silica-induced TNFalpha release, the neutralizing antibody (HTA125) against human TLR4 receptor was employed to pretreat THP-1 cells prior to silica treatment. Moreover, murine macrophages expressing wild type or mutated TLR4 were also treated with silica to verify the effect of TLR4 in silica-induced TNFalpha release.

RESULTSCompared with the control group [(3.18 +/- 0.41) pg/ml], the TNFalpha release in cells exposed to 100 microg/ml silica for 4 h and 8 h [(4.71 +/- 0.84), (6.22 +/- 0.58) pg/ml, respectively] increased 1.48 and 1.96 fold, respectively. Pretreatment of THP-1 cells with 20 microg/ml HTA125 antibody significantly blocked silica-induced TNFalpha release by 27%. Furthermore, the TNFalpha content released from cells expressing mutated TLR4 reduced by 30% in compared with that from the cells expressing wild type TLR4 after silica stimulation.

CONCLUSIONTLR4 mediates silica-induced TNFalpha release from macrophages.

Antibodies ; pharmacology ; Cell Line ; Humans ; Macrophages ; drug effects ; metabolism ; Silicon Dioxide ; toxicity ; Toll-Like Receptor 4 ; immunology ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo investigate the protein expression of transforming growth factor-beta(1) (TGF-beta(1)) in lung tissues of silica-treated mice.

METHODSThe experimental mice were divided into control and silica groups. 0.2 g/kg body weight of silica was injected intratracheally in mice of silica group. Samples of lung tissue were collected 1, 3, 5, 7, 14 and 28 d after injection. The immunohistochemical method was used to analyze the protein expression of TGF-beta(1).

RESULTSIn control mice, the expression of TGF-beta(1) in lung tissue was slightly positive while it was markedly increased in silica-treated mice. The expression was significantly elevated from the 7th day to 14th day. The expression in alveolar macrophages reached the peak on the 5th day [(93.4% +/- 2.8%) vs (42.2% +/- 12.0%), P < 0.01].

CONCLUSIONTGF-beta(1) may play an important role in early development of silicosis.

Animals ; Immunohistochemistry ; methods ; Lung ; chemistry ; drug effects ; pathology ; Male ; Mice ; Pulmonary Fibrosis ; etiology ; pathology ; Silicon Dioxide ; pharmacology ; toxicity ; Silicosis ; etiology ; pathology ; Time Factors ; Transforming Growth Factor beta ; analysis