ABSTRACT
Dental caries, a chronic infectious disease characterized by tooth mineral loss caused by plaque, is one of the major global public health problems. Silver diamine fluoride (SDF) has been proven to be a highly effective anti-caries drug due to its high bacterial inhibition and remineralization ability. However, the SDF solution is unstable, which immensely limits its clinical application. Therefore, new silver-load clay named AgF@Hec was designed by replacing the NH3with hectorite in this study. Fourier transform infrared spectroscopy and x-ray diffraction spectroscopy were employed to confirm the structure of AgF@Hec. Dynamic light scattering analysis was used to reveal the effect of different hectorite concentrations on the stability of AgF@Hec. Moreover, AgF@Hec exhibits significant remineralization and hardness recovery of the initial carious lesions. Bacteriostatic experiments also proved that it has a significant inhibitory effect onA. Viscosus, S. mutans, S. sanguinis, S. salivarius, Lactobacillus sp.and both gram-positive and gram-negative bacteria. We therefore believed that AgF@Hec should be a promising biomaterial that can be applied in the prevention of dental caries.
Subject(s)
Clay , Dental Caries , Quaternary Ammonium Compounds , Silver Compounds , Silver , X-Ray Diffraction , Dental Caries/prevention & control , Clay/chemistry , Silver Compounds/chemistry , Silver Compounds/pharmacology , Spectroscopy, Fourier Transform Infrared , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/pharmacology , Silver/chemistry , Silver/pharmacology , Fluorides/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Tooth Remineralization/methods , Streptococcus mutans/drug effects , Humans , Hardness , Materials Testing , Animals , Microbial Sensitivity Tests , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Fluorides, TopicalABSTRACT
Osteoarthritis (OA) is the most prevalent musculoskeletal disorder and the leading cause of joint disability in elderly patients. In this study, we fabricated strontium chondroitin sulfate (SrCS), a new polysaccharide-metal ion complex that is the combination of chondroitin sulfate and strontium, which are two widely adopted chemicals in OA clinical management. The structural, chemical compositions and morphology of as-fabricated SrCS were systematically investigated. Cell proliferation test, RT-PCR and preliminary animal studies were conducted to evaluate the clinical potential of SrCS on OA treatment. The materials characterization results verified that the Sr was successfully integrated into CS by replacing sodium in the original structure and formed a new polysaccharide-metal ion complex. The cell proliferation results indicated that the SrCS has excellent biocompatibility for both chondrocyte and osteoblast. The RT-PCR results showed that the SrCS can significantly increase the expression of COLII and ACAN, decrease MMP1 and MMP13 in chondrocyte and decrease the IL-6 and IL-1ß in both chondrocyte and osteoblast. Preliminary animal studies demonstrated that SrCS can effectively simulate the articular cartilage formation in SD-rats after modified Hulth's OA modeling surgery. We therefore believed that the SrCS should be a rather effective chemical for OA clinical management as well as a beneficial component for various biomaterials in cartilage tissue engineering.
Subject(s)
Chondrocytes/drug effects , Chondroitin Sulfates/chemical synthesis , Chondroitin Sulfates/pharmacology , Osteoarthritis/physiopathology , Strontium/chemistry , Animals , Cartilage, Articular/drug effects , Humans , RatsABSTRACT
The TRAMO/SEATS program, combined with the Hodrick-Prescott (HP) filter, was used to detect trends and potential change points in time series of dissolved inorganic nitrogen (DIN) at three stations along the Yangtze River. The trend components were extracted, and two change points were successfully detected. The components revealed that DIN has been increasing at all the stations since the 1990s, although variations exist. Changes visible before 2002 illustrate the differences in agriculture development among regions upstream from the stations. The Three-Gorges Dam (TGD), which began to impound in 2003, led to years of different trends. The DIN concentration, which had been trending upward prior to that date, began a slightly downward trend because of NH4(+) depletion. Readings at the Yichang station revealed this trend most strongly; those at the Hankou station less so. The Datong station was far enough away from the TGD so that no obvious effects were seen.
Subject(s)
Environmental Monitoring , Nitrogen/analysis , Rivers/chemistry , Water Pollutants, Chemical/analysis , Water Pollution, Chemical/statistics & numerical data , ChinaABSTRACT
Comprehensively, this paper evaluated the actual vaccination coverage rates in Jiangsu province, using geometric averages to weigh vaccination coverage rates through a) regular and irregular investigation b) conventional report rates and c) registration rates of children at the right age of vaccination. Results showed that the comprehensive method of using vaccination coverage rates for evaluation was better than the conventioned index which had been used before.
Subject(s)
Communicable Disease Control , Vaccination/statistics & numerical data , Child , Child, Preschool , China , Female , Humans , Immunization Schedule , Infant , MaleABSTRACT
Effect of procainamide on platelet adhesion in rats was studied with the improved rotating glass sphere method. Procainamide of 136.0, 34.0, 8.5 mumol.L-1 in vitro and 10 mg.kg-1 in vivo inhibited significantly the platelet adhesion with the inhibitory rates of 56%, 28%, 8%, and 24%, respectively. It showed that procainamide given in vitro or in vivo produced an inhibition on platelet adhesion.