[Effect of peroxisome proliferator-activated receptor-γ on endothelial cells oxidative stress induced by Porphyromonas gingivalis].

OBJECTIVE: To detect the degree of oxidative stress in the process when Porphyromonas gingivalis (P. gingivalis) stimulates human vascular endothelium, And to investigate the effect of peroxisome proliferator-activated receptor(PPAR)γ on oxidative stress during this process. METHODS: Human vascular endothelial cells (HVECs) line EA.hy926 (American Type Culture Collection ,United States) was cultured in high glucose Dulbecco's modified eagle medium (DMEM). Four groups were designed: control group, P. gingivalis infected group, PPARγ activated group and PPARγ blocked group. In control group HVECs were cultured with only DMEM. In P. gingivalis infected group, HVECs were time-dependently stimulated by P. gingivalis W83 from 0 to 12 h. In PPARγ activated group or PPARγ blocked group, PPARγ was pre-activated or blocked by a representative PPARγ agonist(15d-PGJ2 10 µmol/L) or antagonist (GW966210 µmol/L) 30 minutes before the cells were stimulated by P. gingivalis. At 0, 0.5, 1, 1.5, 2, 4, 8, and 12 h, the culture medium was collected individually and centrifuged, and the supernatant was stored for assay. Glutathione peroxidase (GSH-PX) and malondialdehyde (MDA) were analysed by enzyme-linked immunosorbent assay. Cellular reactive oxygen species (ROS) were detected through 2',7'-dichlorofluorescin diacetate (DCFA-DA) fluorescent probe at various time points of the different groups. RESULTS: In P. gingivalis infected group, the levels of GSH-PX [(5.56±0.97) µmol/L] and MDA [(0.84±0.18) nmol/L] were significantly higher than those in control group [GSH-PX(4.71±0.64) µmol/L, MDA (0.59±0.18) nmol/L)]. The levels of GSH-PX and MDA in PPARγ activated group [GSH-PX (5.38±0.84) µmol/L, MDA (0.84±0.22) nmol/L] and in PPARγ blocked group [GSH-PX (5.37±0.76) µmol/L, MDA (0.85±0.14) nmol/L] were significantly higher than those in control group (P<0.05). In the PPARγ activated group, the levels of GSH-PX at 0.5 and 8 h were significantly higher than those from 1.5 h to 4 h (P<0.05), while no difference was observed on the MDA levels at different time points. There was no significant difference at various time points for the levels of GSH-PX and MDA in PPARγ blocked group. The level of cellular ROS detected by DCFH-DA in P. gingivalis infected group was significantly higher than that in control group (10 108.65 ± 1 805.18 vs. 6 049.06 ± 1 199.19,P<0.05). No difference was observed between PPARγ activated group (7 120.94±1 447.30) or PPARγ blocked group (6 727.35±1 483.68) and control group. CONCLUSION: Oxidative stress happens when P. gingivalis stimulates human vascular endothelium. PPARγ may involve in modulating oxidative stress during this process.

Rational design and fabrication of monophasic bioceramic microspheres with enhanced mechanical and biological performances in reconstruction of segmental bone defect.

Over the past decades, there has been extensive study on the design of porous bioceramic scaffolds with controlled bioactivity and biodegradation in bone tissue repair. A variety of suggestive models and concepts have been proposed with regard to the role of microstructure and composition of biomaterials which affect new bone tissue growth. However, it is a challenge to fabricate functional scaffolds with the desired physiological properties and osteogenic potentials that is comparable to the bone's natural healing time scale. We demonstrate a one-step versatile fabrication of a single-phase and homogenously mixed bioactive load-bearing scaffolds (Sr-CS, CaSiO3/Ca2SiO4, and CaP) with superior biological properties in a critical size bone defect (Ø ~ 6.0 × 8.0 mm). In vivo study revealed the CaSiO3/Ca2SiO4 scaffold had the best amount of new bone growth and osteogenic repair. The Sr-CS exhibited an adequate pore network for rapid inorganic exchange and moderate mechanical stability; however, the CaSiO3/Ca2SiO4 saw over-fast resorption and mass loss compared to the Sr-CS and CaP. On the other hand, the CaP scaffold saw mechanically outstanding elastroplastine and stability but had limited biodegradation of its constructs which retarded new cancellous bone growth. The CaSiO3/Ca2SiO4 group saw superior acceleration and formation of mineralized new bone tissues in the defect. Moreover, the CaSiO3/Ca2SiO4 showed appreciable decay of the biomaterials beneficial for osteogenic cell activity. The dramatic stimulation of bone repair and angiogenesis with the CaSiO3/Ca2SiO4 suggests a promising application of this novel bioactive scaffold in the repair of skeletal defects. Systemic representation of the fabricated microspheres with in vivo and in vitro study analysis.

Development and validation of a prokaryotically expressed foot-and-mouth disease virus non-structural protein 2C'3AB-based immunochromatographic strip to differentiate between infected and vaccinated animals.

BACKGROUND: Foot-and-mouth disease (FMD) is an extremely contagious viral disease of cattle, pigs, sheep, goats, and many cloven-hoofed wild animals. FMDV serotypes O and Asia 1 have circulated separately in China during the last fifty years, and eliminating infected animals and vaccination are the main policies to prevent and control FMD. Antibodies to NSPs exist in infected animals, and were utilized to differentiate between infected and vaccinated animals. The reliability of detection of 3AB or 3ABC antibodies is higher than that of other NSPs. The test of 3AB is still credible because 3C protein's immunogenicity is the weakest. The 2C protein, immediately N-terminal of 3AB, was used to differentiate between infected and vaccinated animals. The use of the immunochromatographic strip is facile for clinical laboratories lacking specialized equipment and for rapid field diagnosis. RESULTS: In this study, an immunochromatographic strip with non-structural protein (NSP) 2C'3AB was developed and validated to differentiate foot-and-mouth disease infected from vaccinated animals. A part of N-terminal of 2C protein gene and whole 3AB gene were connected and prokaryotically expressed as the antigens labeled with colloidal gold was used as the detector, the 2C'3AB protein and rabbits anti-2C'3AB antibodies were blotted on the nitrocellulose(NC) membrane for the test and control lines, respectively. 387 serum samples were collected to evaluate the characteristics of the strip in comparison with existing commercial 3ABC antibody ELISA kit. The coincidence rate of pigs negative serum, pigs vaccinated serum, pigs infected serum was 100%, 97.2%, 95.0%, respectively. The coincidence rate of cattle negative serum, cattle vaccinated serum, cattle infected serum was 100%, 96.7%, 98.0%, respectively. The coincidence rate of sheep negative serum, sheep infected serum was 97.6%, 96.3%, respectively. The strip was shown to be of high specificity and sensitivity, good repeatability and stability. CONCLUSION: These data suggest that the immunochromatographic strip is a useful tool for rapid on-site diagnosing animals infected foot-and-mouth disease virus.

Occurrence of Maxillary Central Diastema between Tooth-supported and Implant-supported Prostheses: a 5-year Clinical Follow-up.

A 27-year-old patient with a history of maxillary anterior tooth trauma presented with a maxillary central diastema between tooth- and implant-supported prostheses that had been in use for 5 years. The all-ceramic crowns were placed in 2012 after rigorous occlusal adjustment. Evaluations were carried out at 0, 2, 3, 4 and 5 years post restoration. The central diastema between the natural teeth and the implant-supported prosthesis on teeth 11 and 12 was first observed 2 years after implantation. After 5 years, the distance was found to have increased, with anterior occlusion and esthetic changes having taken place. The following possible causes were discussed: occlusal problems, anterior traumatic effects, the possible impact of guided bone regeneration (GBR) on the adjacent natural teeth and natural movement. More predictive information should be given to patients with implant-supported prostheses and natural teeth so that they are fully informed of the impact of any necessary clinical compromise and are aware of the modifications that may occur to their natural dentition.

Osteogenic potential of human periosteum-derived progenitor cells in PLGA scaffold using allogeneic serum.

The use of periosteum-derived progenitor cells (PCs) combined with bioresorbable materials is an attractive approach for tissue engineering. The aim of this study was to characterize the osteogenic differentiation of PC in 3-dimensional (3D) poly-lactic-co-glycolic acid (PLGA) fleeces cultured in medium containing allogeneic human serum. PCs were isolated and expanded in monolayer culture. Expanded cells of passage 3 were seeded into PLGA constructs and cultured in osteogenic medium for a maximum period of 28 d. Morphological, histological and cell viability analyses of three-dimensionally cultured PCs were performed to elucidate osseous synthesis and deposition of a calcified matrix. Furthermore, the mRNA expression of type I collagen, osteocalcin and osteonectin was semi-quantitively evaluated by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). The fibrin gel immobilization technique provided homogeneous PCs distribution in 3D PLGA constructs. Live-dead staining indicated a high viability rate of PCs inside the PLGA scaffolds. Secreted nodules of neo-bone tissue formation and the presence of matrix mineralization were confirmed by positive von Kossa staining. The osteogenic differentiation of PCs was further demonstrated by the detection of type I collagen, osteocalcin and osteonectin gene expression. The results of this study support the concept that this tissue engineering method presents a promising method for creation of new bone in vivo.

Development of oral dispersible tablets containing prednisolone nanoparticles for the management of pediatric asthma.

The purpose of the present study was to develop oral dispersible tablets containing prednisolone (PDS)-loaded chitosan nanoparticles using microcrystalline cellulose (MCC 101), lactose, and croscarmellose sodium (CCS). The PDS-loaded chitosan nanoparticles were formulated by ionotropic external gelation technique in order to enhance the solubility of PDS in salivary pH. Prepared nanoparticles were used for the development of oral fast disintegrating tablets by direct compression method. The prepared tablets were evaluated for disintegration time (DT), in vitro drug release (DR), thickness, weight variation, drug content uniformity, friability, and hardness. The effect of concentrations of the dependent variables (MCC, lactose, CCS) on DT and in vitro DR was studied. Fast disintegrating tablets of PDS can be prepared by using MCC, CCS, and lactose with enhanced solubility of PDS. The minimum DT was found to be 15 seconds, and the maximum DR within 30 minutes was 98.50%. All independent variables selected for the study were statistically significant. Oral fast disintegrating tablets containing PDS nanoparticles could be the better choice for the pediatric patients that would result in better patient compliance. From this study, it can be concluded that fast disintegrating tablets could be a potential drug delivery technology for the management of asthma in pediatrics.

Development and validation of a lateral flow immunoassay using colloidal gold for the identification of serotype-specific foot-and-mouth disease virus O, A and Asia 1.

A lateral flow immunoassay (LFI) was developed to identify and diagnose foot-and-mouth disease virus (FMDV) serotypes O, A and Asia 1. Antibodies obtained from rabbits and guinea pigs immunized with cell-culture-adapted virus strains (O/CHA/99, A/GS/LX/66, Asia 1/CHN/05) and suckling-mouse adapted virus strains (O/AV99(L), A/AV88(L), Asia 1/YNBS/58) were used as capture antibodies. The diagnostic kit included three immunochromatographic strips of types O, A and Asia 1, and the type-specific results were confirmed by color on the test lines of the three strips. The LFI was evaluated using epithelial and vesicular samples (n=396) prepared from current and historical field samples (provide by the National Foot-and-Mouth Disease Reference Laboratory of China at Lanzhou Veterinary Research Institute). Negative samples (n=95) were collected from healthy animals. The diagnostic sensitivity of the LFI for FMDV serotypes O, A and Asia 1 was 88.3% compared to 89.7% obtained by the reference method of indirect-sandwich ELISA. The sensitivity of the LFI for FMDV type Asia 1 was higher at 92.1% compared to 90.5% for the ELISA. The specificity of the LFI was 97.1% compared with 97.4%.

A simple and rapid colloidal gold-based immunochromatogarpic strip test for detection of FMDV serotype A.

A sandwich format immunochromatographic assay for detecting foot-and-mouth disease virus (FMDV) serotypes was developed. In this rapid test, affinity purified polyclonal antibodies from Guinea pigs which were immunized with sucking-mouse adapted FMD virus (A/AV88(L) strain) were conjugated to colloidal gold beads and used as the capture antibody, and affinity purified polyclonal antibodies from rabbits which were immunized with cell-culture adapted FMD virus (A/CHA/09 strain) were used as detector antibody. On the nitrocellulose membrane of the immunochromatographic strip, the capture antibody was laid on a sample pad, the detector antibody was printed at the test line(T) and goat anti-guinea pigs IgG antibodies were immobilized to the control line(C). The lower detection limit of the test for a FMDV 146S antigen is 11.7 ng/ml as determined in serial tests after the strip device was assembled and the assay condition optimization. No cross reactions were found with FMDV serotype C, Swine vesicular disease (SVD), Vesicular stomatitis virus (VSV) and vesicular exanthema of swine virus (VES) viral antigens with this rapid test. Clinically, the diagnostic sensitivity of this test for FMDV serotypes A was 88.7% which is as same as an indirect-sandwich ELISA. The specificity of this strip test was 98.2% and is comparable to the 98.7% obtained with indirect-sandwich ELISA. This rapid strip test is simple, easy and fast for clinical testing on field sites; no special instruments and skills are required, and the result can be obtained within 15 min. To our knowledge, this is the first rapid immunochromatogarpic assay for serotype A of FMDV.

[Investigation of oral health status in freshmen of university students].

OBJECTIVE: To investigate the oral health status of freshmen of university students and to guide their oral hygiene behaviors. METHODS: 6,575 freshmen of Peking University students were investigated in this study according to the criterion issued by World Health Organization (WHO) on the basic methods of oral health investigation and China oral health epidemiology survey protocol. The inspection item included caries, gingivitis, malocclusions and impacted teeth. RESULTS: In 6,575 freshmen of university students, the prevalence rate of caries, gingivitis, malocclusions and impacted teeth were 35.47%, 60.87%, 19.70% and 24.62%, respectively. There were statistical significance between the prevalence rate of caries, gingivitis, malocclusions and impacted teeth of male and female (chi2=131.94, P<0.001: chi2=216.85, P<0.001; chi2=14.54, P<0.01; chi2=23.56, P<0.001). There were statistical significance between the prevalence rate of caries, gingivitis and impacted teeth of postgraduate and undergraduate (chi2=4.62, P<0.05: chi2=129.56, P<0.001; chi2=178.05, P<0.001), while there was no statistical significance between the prevalence rate of malocclusions of postgraduate and undergraduate (chi2=0.61, P>0.05). CONCLUSION: The oral health status of freshmen of university students are not ideal. It is necessary to strengthen the propaganda education of prevention and protect to freshmen of university students.

[Establishment of a colloid gold-immunochromatography assay for detection of type Asia I foot-and-mouth disease virus].

AIM: To establish a colloid gold-immunochromatography assay (GICA) for detecting type Asia I foot-and-mouth disease virus (FMDV). METHODS: Colloidal gold was obtained by reducing the gold chloride with sodium citrate and then it was coupled with the purified anti-FMDV type Asia I antibody.The purified anti-FMDV type Asia I antibody and the goat anti-Guinea pig IgG were wrapped onto the nitrocellulose membrane as test line (T line) and control line (C line). The GICA strip was assembled with the purified antibody labelled with colloidal gold and the nitrocellulose containing antibody. The sensitivity, specificity and stability of GICA strip were evaluated in the diagnosis of FMD viral antigen from clinical samples. RESULTS: The strip was highly sensitive to FMDV type Asia I(0.116 mg/L) and it had the same result for positive specimens tested thrice. Cross tests proved no cross reaction was found with other serotype FMDV and Swine vesicular disease (SVD) antigen.The corresponding rate of GICA with RIHA was 96.87% for detecting the field sample. The stably test found the strip could be stored for 12 months. CONCLUSION: The GICA strip is a simple and rapid immunochromatographic test strip for the detection of FMDV type Asia I with high sensitivity and specificity.

[Using fenestration and decompression technique to treat enormous odontogenic keratocyst].

3 cases of enormous odontogenic keratocyst were treated with the technique of fenestration and decompression other than removal of jaws. After a follow-up period of two years, radiographic assessment showed that the image of keratocyst disappeared basically, neogenetic bone had been found and the defect of jaws had been restored. The teeth had no dysfunction, the lower lip had no numbness and the keratocyst epithelium was modulated histologically to mucosa after decompression. Fenestration and decompression are satisfied conservative approaches to treat enormous keratocyst which usually is treated by removal of jaws and extraction of teeth.