Search

Interleukin-25 (IL-25) has been recognized as a new member of the IL-17 family and implicated in various inflammatory pathology. We aimed to investigate the effects of IL-25 on the expression of matrix metalloproteinase-2 (MMP-2), MMP-8, and MMP-9 in periodontal fibroblast cells (PFCs), cell migration, cytoskeleton F-actin, and to explore the involved extracellular-regulated protein kinases (ERKs), P38 mitogen-activated protein kinase (P38MAPK) signaling pathways, and IL-17 receptor. To evaluate the expression of MMP-2, MMP-8, MMP-9, and F-actin, PFCs were treated by various doses of IL-25 (0, 20, 50, 100, and 500 ng/ml). Protein expression of extracellular metalloproteinase inducer (EMMPRIN) was also evaluated by western blot. Cell scratches experiment was performed to test the cell migration ability. ERK, P38MAPK, and Jun N-terminal kinase signal pathways and related expression of P-ERK and P-P38MAPK were examined after treatment of different doses of IL-25 and after treatment of inhibitors of ERK and P38MAPK. Immunofluorescence of MMP-2, MMP-9, and F-actin were evaluated after inhibitor treatment. IL-17RB small interfering RNA was used to examine the receptor of IL-25. IL-25 increased the protein expression of MMP-2 and MMP-9. MMP-8 and EMMPRIN expressions were not regulated by IL-25 in PFCs. Positive IF staining extended strongly from the central part to the whole cell. IL-25 mediated MMP-2, MMP-9, F-actin expressions and cell migration were regulated by P38MAPK and ERK pathways, and IL-17RB. SB203580 and U0126 blocked the effects of IL-25 through the inhibition of ERK, P38MAPK, P-ERK, and P-P38MAPK. The data indicate that IL-25 could regulate cell migration, MMP-2, and MMP-9 expression, but not MMP-8 expression, in PFCs. Moreover, the regulation effects were involved in ERK and P38MAPK pathways, and receptor IL-17RB.

The purposes of this study were to construct a novel tissue engineered bone composed of 3D-printed bioactive glass block/chitosan nanoparticles (BD/CSn) composites loaded with Nel-like Type I molecular-1 DNA (pDNA-NELL1) and/or bone marrow mesenchymal stem cells (BMSCs), and study their osteogenic activities by repairing bone defects in rhesus monkeys. CSn with NELL1 gene plasmid and rhesus monkey BMSCs were composited with a BD scaffold to prepare the tissue-engineered bone. Four adult female rhesus monkeys with 10- to 12-years old and 5–7 kg in weight were used in animal experiments. The first and second premolar teeth from four regions of each monkey were removed to form bone defects with size of 10 × 10 × 5 mm, which were then implanted with above-mentioned tissue engineered bone. At 12 weeks after the implantation, gross observations, X-ray and micro-CT observations revealed that the new bone was extremely close to normal bone in mass, density, hardness, and structure. The bony cortex was smooth and closely connected to the surrounding normal bone. Histological observations revealed moderate inflammation in the repair area, and the new bone tissues were similar to normal ones. In conclusion, tissue engineered bone of this study exhibited good osteoconductivity for promoting the formation of new alveolar bone tissue, and NELL1 gene played a promotional role in bone regeneration.

Background and Objective Extracellular matrix metalloproteinase inducer (EMMPRIN) is a transmembrane glycoprotein that may induce activation of matrix metalloproteinases (MMPs) and lead to the destruction of periodontal tissue. The level of EMMPRIN glycosylation might be involved in this process. This study aims to investigate the role of EMMPRIN glycosylation in regulating MMP-2 and MMP-9 during the progression of periodontitis. Material and Methods Gingival tissues were collected from patients with chronic periodontitis and from patients undergoing crown-lengthening procedures (healthy gingival tissue). Tissues were used for immunohistochemistry and double immunofluorescence. A human immortalized oral epithelial cell (HIOEC) line was stably transfected by an N-acetylglucosaminyltransferase-V (GnT-V) RNA interference (RNAi) lentivirus to suppress EMMPRIN glycosylation. Gene silence efficiency was detected by western blot, quantitative real-time PCR and immunofluorescence (IF) staining. An HIOEC/human gingival fibroblast (HGF) co-culture model and an individual culture model were used in this study. After exposure of cells to Porphyromonas gingivalis lipopolysaccharide (Pg. LPS), the expression of EMMPRIN, MMP-2 and MMP-9 were assessed by western blot, quantitative real-time PCR and IF, and the secretion of MMP-2 and MMP-9 were detected by gelatin-degradation assays. Results Compared with the periodontally healthy group, patients with periodontitis showed increased expression of EMMPRIN on the gingival epithelial cell membrane. GnT-V, a key regulator of EMMPRIN glycosylation, was co-expressed with EMMPRIN in gingival epithelial cells in patients with periodontitis. Knockdown of GnT-V reduced the level of EMMPRIN glycosylation in HIOECs. Furthermore, in the HIOEC/HGF co-culture model, stimulation with Pg. LPS (10 μg/mL, 4 hours) promoted EMMPRIN glycosylation and increased the activities of MMP-2 and MMP-9, while suppression of EMMPRIN glycosylation by GnT-V knockdown reduced the synthesis and activities of MMP-2 and MMP-9 under Pg. LPS stimulation. Moreover, the gelatin-degradation assay showed that inhibition of EMMPRIN glycosylation suppressed the Pg. LPS-induced degradation of gelatin in the co-culture model. Conclusion We conclude that EMMPRIN glycosylation participates in the regulation of MMP-2 and MMP-9 production through mediating the interaction of HIOECs and HGFs. Inhibiting EMMPRIN glycosylation can reduce the activation of MMP-2 and MMP-9 and suppress the degradation of extracellular matrix (ECM) in the HIOEC/HGF co-culture model. Therefore, this study suggests that EMMPRIN glycosylation may affect the host immune-inflammatory response by regulating MMPs in periodontitis.

All-organic polyimide (PI)/poly(vinylidene fluoride) (PVDF) dielectric composites were fabricated via two synthesis methods. The dielectric and thermal properties of the PI/PVDF composites were investigated. The results indicated that the dielectric properties of the composites synthesized by these two methods were enhanced through the introduction of PVDF, and the composites exhibited excellent thermal stability. In addition, the composites prepared by solution blending exhibited superior dielectric properties and thermal properties compared with the composites prepared by in situ polymerization.

Three types of polyacene quinone radical (PAQR) polymers were synthesized by the step-growth polymerization of naphthalene, anthracene, or anthraquinone reacting with pyromellitic dianhydride via solution polymerization under a temperature gradient. Zinc chloride was used as the catalyst, and nitrobenzene was the solvent. The different structures of PAQR polymers were analyzed by infrared, X-ray diffraction, and scanning electron microscopy. The thermal properties of PAQR polymers were described by thermal gravimetric analysis, and the electrical performances were investigated by a precision LCR meter and a digital high insulation meter.

Atorvastatin has been shown to affect cognitive functions in rodents and humans. However, the underlying mechanism is not fully understood. Because hippocampal gamma oscillations (γ, 20-80 Hz) are associated with cognitive functions, we studied the effect of atorvastatin on persistent kainate-induced γ oscillation in the CA3 area of rat hippocampal slices. The involvement of NMDA receptors and multiple kinases was tested before and after administration of atorvastatin. Whole-cell current-clamp and voltage-clamp recordings were made from CA3 pyramidal neurons and interneurons before and after atorvastatin application. Atorvastatin increased γ power by ~ 50% in a concentration-dependent manner, without affecting dominant frequency. Whereas atorvastatin did not affect intrinsic properties of both pyramidal neurons and interneurons, it increased the firing frequency of interneurons but not that of pyramidal neurons. Furthermore, whereas atorvastatin did not affect synaptic current amplitude, it increased the frequency of spontaneous inhibitory post-synaptic currents, but did not affect the frequency of spontaneous excitatory post-synaptic currents. The atorvastatin-induced enhancement of γ oscillations was prevented by pretreatment with the PKA inhibitor H89, the ERK inhibitor U0126, or the PI3K inhibitor wortmanin, but not by the NMDA receptor antagonist D-AP5. Taken together, these results demonstrate that atorvastatin enhanced the kainate-induced γ oscillation by increasing interneuron excitability, with an involvement of multiple intracellular kinase pathways. Our study suggests that the classical cholesterol-lowering agent atorvastatin may improve cognitive functions compromised in disease, via the enhancement of hippocampal γ oscillations.

Background/purpose: Inducing human-periodontal-ligament-stem-cell (hPDLSC) differentiation by DNA transfection is a promising way for periodontal tissue engineering. However, there are only a few studies that focus on the introduction of foreign DNA into hPDLSCs by nonviral methods that are relatively safe. Hence, the major purposes of this study were to compare the transfection efficiency and toxicity of nonviral-gene-transfer methods on hPDLSCs, and to search for the best approach and optimal protocol for transferring genes into hPDLSCs using nonviral vectors. Materials and methods: The hPDLSCs were transfected by (1) Lipofectamine 2000, (2) polyethylenimine, (3) GBfectene-Elite transfection reagent, (4) X-tremeGENE HP DNA Transfection Reagent, and (5) Magnet-Assisted Transfection (MATra), compared to (6) lentiviral vectors harboring a green-fluorescent-protein gene. The transfection efficiency was measured by a fluorescence microscope and flow cytometry. Meanwhile, the cell morphology and growth status were observed to estimate the cytotoxicity. Results: Among these methods, the transfection efficiency of the former four methods was not very satisfactory (< 6%) compared to that of lentiviral vectors (positive control, 95%). However, MATra was the most effective nonviral method (11%). Moreover, the cellular toxicity was lower than that of the former four methods. Conclusion: The transfection efficiency of hPDLSCs with MATra was higher than the other nonviral transfection reagents in this study, but it was far less than the viral vectors. Saving from the interaction between the positive and negative charges, and increasing the opportunity of contact between the plasmid and the cytomembrane might be the key to enhancing the transfection efficiency for hPDLSCs in application of periodontal tissue engineering.

All-organic polyimide (PI)/poly(vinylidene fluoride) (PVDF) composite materials with high dielectric constant and low dielectric loss were fabricated via solution blending followed by the chemical imidization of polyamic acid (PAA, precursor of PI) at a low temperature. The dielectric and thermal properties of the PI/PVDF composites were investigated. Results indicated that the dielectric properties of the composites were significantly increased due to the incorporation of PVDF, and the composites exhibited excellent thermal stability. The dielectric constant of the composites was sharply increased to 7.745 at 1 kHz, which was approximately 2.1 times higher than that of pure PI. The dielectric loss was only 0.0898 when PVDF content was as high as 50 wt.%. Moreover, the dependence of the dielectric constant and dielectric loss on frequency was studied. Within the testing frequency range of 100 Hz–1 MHz, the dielectric constant of the composites slightly decreased and the dielectric loss was less than 0.12. The results demonstrated that the PI/PVDF composites were promising dielectric materials for modern electronic applications.

Background and Objective Puerarin, the most abundant isoflavonoid in kudzu root, shows various bioactivities, including bone-sparing, anti-inflammatory and antiproteinase properties. This study aimed to evaluate the effects of puerarin in a rat model of ligature-induced periodontitis. Material and Methods Rat models of periodontitis were developed by bilaterally placing ligatures around the first mandibular molars. Puerarin was administrated daily by gavage at doses of 100, 200 and 400 mg/kg, starting a day before the placement of ligatures. Rats were humanely killed 7 d after the induction of periodontitis. Micro-computed tomography and sirius red staining were used to evaluate alveolar bone loss and collagen destruction, respectively. Histomorphometrical analysis was used to assess the inflammatory cell infiltration. Immunohistochemistry and tartrate-resistant acid phosphatase were used to detect receptor activator of nuclear factor kappa B ligand and osteoprotegerin expressions, and osteoclast activity in the gingiva and alveolar bone. The activation of nuclear factor-kappa B, production of tumor necrosis factor (TNF)-α and interleukin (IL)-1β, glycosylation of extracellular matrix metalloproteinase inducer, and production of matrix metalloproteinase (MMP)-2 and MMP-9 in the gingiva were assessed by Western blot. Results Puerarin at doses of 200 and 400 mg/kg significantly reduced the alveolar bone loss compared with the vehicle group. Collagen destruction and inflammatory cell infiltration were significantly less in the puerarin-treated group (200 mg/kg) compared with that of the vehicle group. Puerarin (200 mg/kg) also reduced the ratio of receptor activator of nuclear factor kappa B ligand/osteoprotegerin and osteoclast activity. Western blot analysis showed that puerarin (200 mg/kg) inhibited the activation of nuclear factor-kappa B p65, which is associated with lower IL-1β and TNF-α production, and reduced the glycosylation of extracellular matrix metalloproteinase inducer, which is associated with lower levels of MMP-2 and MMP-9. Conclusions Puerarin reduced the alveolar bone loss and collagen destruction in rats with ligature-induced periodontitis by inhibiting the production of RANKL, IL-1β, TNF-α, MMP-2 and MMP-9. Thus, puerarin can be considered a promising agent for adjunctive therapy of periodontitis.

This study aimed to establish a model of synaptic plasticity by the activation of metabotropic glutamate receptor (mGluR) I in rat medial septal diagonal band (MSDB). Electrophysiological experiment was performed to record the theta frequency oscillation activities in rat MSDB slices. The data were recorded and analyzed with Spike 2 (CED, Cambridge, UK). Application of aminocyclopentane-1, 3-dicarboxylic acid (ACPD) to MSDB slices produced theta frequency oscillations (4-12 Hz) which persisted for hours after ACPD washout, suggesting the existence of a form of synaptic plasticity in long-term oscillations (LTOs). Addition of NMDA receptor antagonist AP5 (50 μM) caused no significant change in area power. In contrast, AMPA/Kainate receptor antagonist NBQX administration partially reduced the area power. Infusion of ZD7288, a hyperpolarization-activated channel (Ih) inhibitor, caused additional reduction to control level. Comparable effects were also observed with administration of DHPG (3, 5-dihydroxyphenylglycine) which also elicited LTOs. mGluR I activation induced theta oscillation and this activity maintained hours after drug washout. Both AMPA and hyperpolarization-activated channel make an essential contribution to LTO. Our study herein established a model of synaptic plasticity.

Early detection of cancer often requires time consuming protocols and expensive instrumentation. To address these limitations, a Rose Bengal conjugated gold nanorod (RB-GNR) platform is developed for optical detection of cancer cells. The GNRs are modified by poly(allylamine hydrochloride) and conjugated with RB molecules to produce RB-GNRs which exhibit strong optical absorption in the near-infrared (NIR) region, good stability in aqueous solution, low cytotoxicity, and high specificity to oral cancer cells. The label-free sensing assay utilizes RB-GNRs as the sensing probe and by monitoring the aggregation-induced red-shift in the NIR absorption wavelength, specific and quantitative analysis of the oral cancer cell lysate is accomplished down to a detection limit of 2000 cells/mL. By employing the RB-GNRs as an imaging probe, an imaging assay is established on a home-made NIR absorption imaging system. Based on the NIR absorption by the RB-GNRs specifically conjugated with the oral cancer cells, multi-channel, rapid and quantitative detection of oral cancer cells is demonstrated. The high sensitivity and specificity of the RB-GNR platform as demonstrated by the two complementary assays provide non-invasive optical diagnostics of oral cancer cells enabling convenient screening and monitoring.

Background and Objective Matrix metalloproteinases (MMPs) play important roles in extracellular matrix degradation and may be regulated by extracellular matrix metalloproteinase inducer (EMMPRIN). The aim of this study was to investigate the temporal expression and localization of MMP-8 and MMP-13 during the development of ligature-induced periodontitis in rats, and to analyze the correlations of EMMPRIN with MMP-8 and MMP-13 in periodontitis. Material and Methods Periodontitis was simulated in rats by ligaturing the cervix of the lower first molars, as described in our previous method. The rats were killed 0, 3, 5, 7, 11, 15 and 21 d after ligation. Micro-computed tomography examinations were performed to detect alveolar bone loss. Semiquantitative western blotting was used to assess the temporal changes in the levels of MMP-8, MMP-13 and EMMPRIN proteins in gingival tissue. Immunohistochemistry was applied to detect the expression and locations of MMP-8 and MMP-13 in gingival tissue and alveolar bone. Results Alveolar bone loss showed an exponential increase from days 3 to 11, followed by a slower rate of loss at subsequent study time points. MMP-8 showed a rapid increase of expression from baseline to a peak on day 3, a gradual decrease from days 5 to 7 and then stabilized thereafter. MMP-8 was predominantly located in neutrophil-like cells. Statistically, the expression of MMP-8 was not correlated with the expression of EMMPRIN. The expression of MMP-13 and of EMMRPIN increased from days 3 to 7, and showed a moderate decrease thereafter. The immunoreactivity of MMP-13 was mainly detected in monocytes/macrophages, on the alveolar bone surface, in osteoclasts and in gingival epithelial cells. Statistically, MMP-13 had a strong, positive correlation with EMMPRIN (r = 0.855, p

A novel in vivo fluorescence spectroscopic diagnostic method has been developed in an animal model to make a quantified precancer diagnosis. In the study, 40 golden hamsters were randomly divided into four groups (groups A, B, C, and D), with group A being the control group and the other three groups being inducted at different precancer stages. A 1% Rose Bengal (RB) solution was used for the fluorescence spectroscopic diagnosis. A parameter K defined as K = I(RB)/I(auto) was introduced to reflect the amount of RB in the tissue, where I(RB) and I(auto) represent the fluorescence peak intensity of the RB in the tissue and the autofluorescence intensity of tissue at 580 nm, respectively. The average K values of the four groups were calculated and statistically analyzed by analysis of variance (ANOVA), which revealed statistically significant differences within each group as well as between groups (p0.001). After analysis by Clementine 11.1 CR Tree modeling (CART), the following diagnostic criteria were set: normal, K ≤ 8.91; simple hyperplasia, 8.91K ≤ 41.92; mild dysplasia, 41.92K ≤ 70.79; moderate and severe dysplasia, K70.79. The sensitivity and specificity to detect precancerous lesions compared with scalpel biopsy were calculated. The results of this study showed that the spectrofluorometric method mediated by RB could accurately discriminate different precancer stages.

Background and Objective: Extracellular matrix metalloproteinase inducer (EMMPRIN), an immunoglobulin-like cell surface glycoprotein, could promote collagenolytic balance in favor of the expression and activation of matrix metalloproteinases (MMPs). This study was to investigate the expression of EMMPRIN in gingival tissues from different periodontal conditions and to correlate it with the production of MMP-1 and MMP-2. Material and Methods: Gingival biopsies were collected from 15 patients with untreated advanced chronic periodontitis and 15 patients with aggressive periodontitis (AgP). The control group consisted of 12 subjects diagnosed either as periodontally healthy individuals or as individuals with a gingival index of one (H/G1). The peptides and mRNA of EMMPRIN, MMP-1 and MMP-2 were detected by immunohistochemistry and semi-quantitative reverse transcriptase-polymerase chain reaction, respectively. Results: The expression of EMMPRIN, MMP-1 and MMP-2 peptides in periodontally healthy tissues was mainly confined to the gingival epithelium. The EMMPRIN was strongly expressed in the cell membrane of the basal layer. Immunoreactivity for EMMPRIN was more intensive and more widespread in periodontitis, extended from the epithelial layers to the underlying connective tissues, and was essential in both inflammatory and fibroblast-like cells. In addition, MMP-1 and MMP-2 showed the same localized expression. The chronic periodontitis group had a significantly higher mRNA expression of EMMPRIN and MMP-2 compared with the H/G1 subjects (p

Early detection of oral precancerous and malignant lesions is still a diagnostic challenge for most of clinicians, and ideal adjuncts for detection of these lesions are currently unavailable. Our preliminary study has indicated that rose bengal (RB) staining might have the potency as a diagnostic aid; however, its clinical significance and reliability in hospital-based population are still not clear. In the present study, we investigated the efficacy of RB staining in detection of oral precancerous and malignant lesions. RB staining was conducted in 132 patients, and staining results were determined by a 4-graded shade guide, which had been quantitatively measured in the 1976 CIEL*a*b* space by instrumental colorimetry. Histological examination was performed in 128 of 132 patients after RB staining. The sensitivity and specificity to detect epithelial dysplasia (DP) and oral squamous cell carcinoma were 93.9 and 73.7%, respectively. The positive and negative likelihood ratios were 3.570 and 0.082, respectively. Moreover, RB staining seemed promising to detect DP in oral leukoplakia, lichen planus and leukokeratosis. In this study, 5 of 6 DP or oral squamous cell carcinoma were identified by RB staining before histological examination. In conclusion, RB staining may be a valuable diagnostic test in detection of oral precancerous and malignant lesions.

Background and Objective Paeoniflorin is the main active ingredient in Radix Paeoniae and has been reported to exhibit obvious anti-inflammatory and immune-regulatory activities. This study aimed to investigate the protective effects of paeoniflorin on alveolar bone destruction and soft-tissue breakdown in experimental periodontitis. As supplementary evidence, we evaluated the related expression of MMP-2, MMP-9, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Material and Methods Twenty-eight rats were randomly placed into the following four groups: healthy group; periodontitis group; periodontitis plus 30 mg/kg of paeoniflorin (P30) group; and periodontitis plus 60 mg/kg of paeoniflorin (P60) group. Periodontitis was induced in rats by placing ligatures around the lower first molars. The body weight of each rat was measured and recorded before and after the experiment. Bone resorption was evaluated using micro-computed tomography. Soft-tissue destruction and collagen fiber degradation were assessed by histologic analysis and picrosirius red staining. The expression levels of MMP-2, MMP-9, iNOS and COX-2 in gingiva were detected by western blotting. Results Periodontal tissues were intact in the healthy group. Alveolar bone level was significantly reduced, and evident inflammation of soft tissues was observed in the periodontitis group. Paeoniflorin significantly prevented alveolar bone loss and inflammatory infiltration in a dose-dependent manner. The collagen fiber fractions were significantly higher in the P30 and P60 groups than in the periodontitis group. The results of the western blot analyses revealed that both 30 and 60 mg/kg of paeoniflorin significantly down-regulated the levels of MMP-2, MMP-9, iNOS and COX-2. Conclusion This study provides the first evidence that paeoniflorin significantly down-regulates inflammatory infiltration and prevents alveolar bone loss and soft-tissue destruction in experimental periodontitis. The anti-inflammatory mechanism of paeoniflorin was further supported, in part, by its inhibitory effect on MMP-2, MMP-9, iNOS and COX-2.

Objective: Photodynamic therapy (PDT) triggers various cellular responses and induces cell death via necrosis and/or apoptosis. This study evaluated the feasibility of using O2 and Ca2+ fluxes as indicators of apoptosis induced by rose bengal (RB)-mediated PDT in human oral squamous carcinoma cells (Cal27 cells). Methods: Intracellular reactive oxygen species (ROS) generation was assessed by the dichloro-dihydro-fluorescein diacetate (DCFH-DA) method. Real-time O2 and Ca2+ flux measurements were performed using the noninvasive micro-test technique (NMT). Apoptosis of the PDT-treated cells was confirmed by 4′6-diamidino-2-phenylindole-dilactate staining. The activation of apoptosis-related molecules was examined using Western blot. We assayed the effects of the fluctuation of O2 and Ca2+ flux in response to PDT and the apoptotic mechanism, by which ROS, O2, and Ca2+ synergistically may trigger apoptosis in PDT-treated cells. Results: Real-time O2 and Ca2+ flux measurements revealed that these indicators were involved in the timely regulation of apoptosis in the PDT-treated cells and were activated 2 h after PDT treatment. RB-mediated PDT significantly elicited the generation of ROS by approximately threefold, which was critical for PDT-induced apoptosis. Cytochrome c and cleaved caspase-3, caspase-9 and poly ADP ribose polymerase (PARP) were overexpressed, and the data provided evidence that 2 h was considered to be the key observation time in RB-mediated PDT-induced apoptosis in Cal27 cells. Conclusions: Our collective results indicated that the effects of O2 and Ca2+ fluxes may act as a real-time biomonitoring system of apoptosis in the RB-PDT-treated cells. Also, RB-mediated PDT can be a potential and effective therapeutic modality in oral squamous cell carcinoma.

In the current work, we succeeded in incorporation of Pt ions into sisal fiber (SF) – a biological matrix with a characteristic morphology of microtube array, and in subsequent in situ synthesis of Pt nanoparticles of ca. 3.6 nm. Carbonization of the SF with Pt nanopaticles at 400°C produced Pt-nanoparticle/carbon-fiber composite, preserving the initial microtube-array morphology of SF. It is interesting that the walls of neighboring microtubes and the middle lamella between these microtubes were fused by carbonization, and a homogeneous wall was formed. Although the size of Pt nanoparticles was enhanced to ca. 5.3 nm after carbonization, the solid matrices (from cellulose to carbon) acted as effective barriers against the growth of Pt nanoparticles. The Pt-nanoparticle/carbon-fiber composite combines several important aspects, including the morphologies of fiber and microtube-array, carbon matrix, and Pt nanoparticles. Thus it might be a novel type of catalyst and have potential applications in many fields.

Hierarchically ordered porous alumina was prepared via a facile immersion-fuming-calcination process using Pueraria lobata as template. The as-prepared alumina inherited nearly all morphological features of the template, as shown by SEM observations. It also contains abundant mesopores based on nitrogen adsorption-desorption measurements. The crystalline phase of the as-prepared alumina was ascertained to be gamma-alumina by analyzing its XRD pattern. Pt nanoparticles were in situ synthesized in the gamma-alumina matrix and annealed at different temperatures in N(2) atmosphere. TEM observations showed that Pt nanoparticles supported by the as-prepared alumina have significantly high thermal stability.

Background and Objective Piperine exhibits anti-inflammatory activity, and has a long history of medicinal use. The objective of this study was to investigate the protective effects of piperine on inflammation, alveolar bone and collagen fibers in experimental periodontitis. We evaluated the related expression of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, matrix metalloproteinase (MMP)-8 and MMP-13 to enhance insight into these effects. Material and Methods Thirty-two Wistar rats were divided into four groups of eight animals each: control group, periodontitis group, periodontitis plus 50 mg/kg piperine group and periodontitis plus 100 mg/kg piperine group. Histopathologic changes were detected by hematoxylin and eosin staining. Alveolar bone loss and trabecula microstructures were evaluated by micro-computed tomography. Changes in collagen fibers were assessed by picrosirius red staining. Western blot analysis was conducted to determine the levels of IL-1β, TNF-α, MMP-8 and MMP-13. Results Piperine clearly inhibited alveolar bone loss and reformed trabecula microstructures in a dose-dependent manner. Histological staining showed that piperine significantly reduced the infiltration of inflammation in soft tissues. Both doses of piperine limited the fractions of degraded areas in collagen fibers. Piperine (100 mg/kg) significantly downregulated the expressions of IL-1β, MMP-8 and MMP-13 in periodontitis, but not that of TNF-α. Conclusion Piperine displays significantly protective effects on inflammation, alveolar bone loss, bone microstructures and collagen fiber degradation in experimental periodontitis. The effects may be ascribed to its inhibitory activity on the expressions of IL-1β, MMP-8 and MMP-13.

Gold nanorods (GNRs) conjugated with rose bengal (RB) molecules exhibit efficient singlet oxygen generation when illuminated by 532 nm green light and high photothermal efficiency under 810 nm near-infrared (NIR) irradiation. In vitro experiments show that reactive oxygen species generated by green light and hyperthermia produced by NIR light constitute two different mechanisms for cancer cell death. The RB-GNRs also exhibit improved photodynamic efficacy by enhancing the uptake of RB by cancer cells. In vivo experiments are conducted on hamster cheek pouches to resemble the human oral cancer conditions more accurately to assess the therapeutic effectiveness. Compared to the single photodynamic therapy (PDT) or photothermal therapy (PTT), the RB-GNRs with combined PDT-PTT capabilities provide better therapeutic effects against oral cancer and have large potential in cancer treatment.

Background and Objective Glycosylated extracellular matrix metalloproteinase inducer (EMMPRIN) is specifically associated with caveolin-1 and influences its ability to induce matrix metalloproteinases (MMPs) production. This study investigated EMMPRIN glycosylation and caveolin-1 expression in healthy and inflamed human gingival tissues, analyzed the relationship between EMMPRIN glycosylation and caveolin-1 expression, and assessed how this interaction influenced MMP-1 production. Material and Methods Gingival tissues were collected from 10 healthy subjects and 15 chronic periodontitis (chronic periodontitis) subjects. EMMPRIN, caveolin-1 and MMP-1 expressions were analyzed by immunohistochemistry. EMMPRIN and caveolin-1 co-localization was detected by immunofluorescence. EMMPRIN glycosylation, caveolin-1, active MMP-1 and proMMP-1 expression was assessed by Western blot. Results EMMPRIN was expressed in gingival epithelial cells, inflammatory cells, endothelial and fibroblast-like cells. Strong caveolin-1 immunoreactivity was detected in gingival epithelial and endothelial cells. Double immunofluorescence studies revealed EMMPRIN and caveolin-1 co-localization in gingival epithelium, endothelial and fibroblast-like cells. Compared with healthy subjects, the chronic periodontitis group had increased high-glycoform EMMPRIN (HG-EMMPRIN) and active MMP-1 expression (p

Cyclic stretch increases Na(+)/K(+)-ATPase activity and abundance in several tissues, including skeletal muscle cells. The present study was undertaken to investigate whether Na(+)/K(+)-ATPase undergoes acute changes in its catalytic activity in response to cyclic stretch. Na(+)/K(+)-ATPase activity increased after continuously stretched for 6 h, and reached the maximum at 24 h. The inhibition of gene transcription (actinomycin D) had no effect on stretch-induced Na(+)/K(+)-ATPase activity. Cyclic stretch also increases the plasma membrane content of α(1)- and α(2)-subunit of Na(+)/K(+)-ATPase. Brefeldin A could completely abolished the stretch-induced recruitment of α-subunits to the plasma membrane and Na(+)/K(+)-ATPase activity. In conclusion, cyclic stretch directly stimulates Na(+)/K(+)-ATPase activity in skeletal muscle cells through post-transcriptional activation, likely by increasing translocation of Na(+)/K(+)-ATPase molecules to plasma membrane.

This paper investigates the design optimization of an electrostatically actuated microcantilever resonator that operates in air. The nonlinear effects of electrostatic actuation and air damping make the structural dynamics modeling more complex. There is a need for an efficient way to simulate the system behavior so that the design can be more readily optimized. This paper describes an efficient analytical approach for determining the optimum design for a microcantilever resonant mass sensor. One simple case is described. The sensor design is a square plate that is coated with a functional polymer and attached to the substrate with folded leg springs. The plate has a square hole in the middle to reduce the effect of squeeze film damping. With the analytical approach, the optimum hole size for maximum sensitivity is found.Copyright © 2009 by ASME

Liu L, Li C, Cai X, Xiang J, Cao Z, Dong W. The temporal expression and localization of extracellular matrix metalloproteinase inducer (EMMPRIN) during the development of periodontitis in an animal model. J Periodont Res 2010; 45: 541–549. © 2010 John Wiley & Sons A/S Background and Objective: We previously demonstrated extracellular matrix metalloproteinase inducer (EMMPRIN) was associated with the matrix metalloproteinases production of human periodontitis. The aim of this study was to investigate the temporal expression and localization of EMMPRIN during ligature-induced periodontitis in rats. Material and Methods: Periodontitis was inducd in rats by placing a thread around the cervix of the first mandibular molar. Animals were killed 3, 7, 11, 15 or 21 d after ligation. Mandibles were processed for paraffin sections and stained with hematoxylin and eosin or picrosirius red. The distance from the amelocemental junction to the alveolar crest (ACJ–AC) and the area fraction (Area%) of collagen fibers were measured. EMMPRIN was examined by immunohistochemistry and quantified by positive cell counting. Correlation analyses were then performed. Results: Histologically, alveolar bone was gradually destroyed from day 3 to 11 and then stabilized. Collagen fibers were slightly dissociated on day 3 and extensively broken on day 7. They were reconstructed from day 11 to 21. EMMPRIN was localized predominantly in infiltrating cells and adjacent fibroblasts in interdental gingiva. The number of EMMPRIN-positive cells increased on day 3, peaked on day 7 and then gradually subsided from day 11 to 21. Statistically, there was a moderate positive correlation regarding the ACJ–AC distance (r = 0.552, p

Our previous research has proved that baicalin can inhibit the expression of Matrix metalloproteinases (MMPs) in periodontal ligament cells (PDLC) by cell immunocytochemistry. Therefore, the purpose of this study was to address the effects of baicalin on the total protein amount and Collagen I mRNA expression in PDLC, and the regulatory effects on Matrix metalloproteinase-1/ tissue inhibitors of metalloproteinase-1( MMP-1/ TIMP-1 ) expression. PDLC were incubated with 0-1000 ng/ml baicalin for 1, 3 and 5 days. Coomassie Brilliant Blue staining was used to detect the synthesis of the total protein, and the collagen I mRNA expression was analyzed by reverse transcription-polymerase chain reaction (RT-PCR). PDLC were treated with phorbol 12-myristate 13-acetate (PMA) or interleukin-1beta (IL-1beta) with or without 100 ng/ml baicalin and then mRNA levels for MMP-1 and TIMP-1 were detected. Enzyme linked immunosorbent assay (ELISA) was used to assess the MMP-1 protein. The range of 1-1000 ng/ml baicalin can enhance the amount of the total protein of PDL cells and the response had a dose-dependent manner in the range of 1-100 ng/ml baicalin. And 0-1000 ng/ml baicalin also significantly increased the Collagen I mRNA expression of PDLC. 1-100 pmol/ml PMA and 0.01-1 ng/ml IL-1beta significantly (p

Supporting and enhancing the regeneration and stability of alveolar bone at dental implant sites is necessary to improve implant integration and stability. In this study chitosan/collagen scaffolds combined with adenoviruses expressing either bone morphogenetic protein 7 (BMP-7), platelet-derived growth factor B (PDGF-B), or a combination of both BMP-7 and PDGF-B, were prepared by a freeze-drying method. The cytotoxicity of the resulting biomaterials, and their potential effects on cell proliferation and differentiation towards an osteoblast phenotype, were studied in an initial in vitro study using human periodontal ligament cells (HPLCs). These in vitro results indicate that the scaffold materials are not cytotoxic, and moreover that scaffolds expressing PDGF-B show a higher proliferation rate, while scaffolds expressing BMP-7 show a stronger differentiation towards the osteoblast phenotype. In a subsequent in vivo study, scaffolds were implanted into surgically induced defects on both sides of the dog mandible. Bone formation, which was evaluated histomorphometrically at 4 and 8 weeks and after sacrificing the animals at 12 weeks, revealed a significant increase in bone formation in scaffolds expressing only BMP-7 and also the combined growth factors, with the highest increase occurring for the scaffold expressing both BMP-7 and PDGF-B. This study demonstrates the promising potential of biomaterial expression of combinations of growth factors such as BMP-7 and PDGF-B for bone regeneration in tissue engineering applications.

A novel class of 2-(2'-hydroxyphenyl)benzothiazole-based (HBT-based) excited-state intramolecular proton-transfer (ESIPT) compounds, N,N'-di[3-Hydroxy-4-(2'-benzothiazole)phenyl]isophthalic amide (DHIA) and N,N'-di[3-Hydroxy-4-(2'-benzothiazole)phenyl]5-tert-butyl-isophthalic amide (DHBIA) has been feasibly synthesized and the properties of their nanoparticles in THF/H2O mixed solvent were investigated. Both compounds were found to exhibit aggregation-induced emission enhancement (AIEE) due to restricted intramolecular motion and easier intramolecular proton transfer in solid state. On identical experimental conditions, the emission of DHBIA aggregates increased more remarkably than that of DHIA. Different aggregation forms of these two organic compounds, due to the steric hindrance of a single tert-butyl group, could be responsible for the notably different degrees of the fluorescence enhancement. Their aggregation modes were investigated on the basis of time-dependent absorption, scanning electron microscope (SEM) images, and molecular modeling with theoretical calculation. The photophysical dynamics were also depicted based on the extremely fast ESIPT four-level cycle.

Baicalin is a flavonoid compound purified from the medicinal plant Scutellaria baicalensis Georgi and has been reported to possess anti-inflammatory activity through its ability to complex with chemokines and thus reduces the capacity of chemokines to bind and activate their receptors. In the present study, we investigated whether baicalin could block polymorphonuclear leukocytes (PMNs) degranulation induced by interleukin (IL)-8, a CXC chemokine. Human PMNs were isolated from the peripheral blood of periodontal healthy donors and incubated with various concentrations of IL-8 (preincubated with or without baicalin). The morphology of PMNs was examined by transmission electron microscopy and extracellular concentration of granule component matrix metalloproteinase-8 (MMP-8) was detected by enzyme-linked immunosorbent assay (ELISA). Results showed that IL-8 could significantly induce MMP-8 release from PMNs when compared to control, and its inductive activity was concentration-dependent. But when preincubated with various concentrations of baicalin, the amount of MMP-8 release from PMNs decreased significantly. The present study concludes that baicalin could block MMP-8 release from PMNs induced by IL-8, which suggests that it may play an important role in the prevention and treatment of periodontal disease.

An easy approach to synthesis of silica nanofibers and nanotubes via wrapping sacrificial Cd(OH)2 nanostrands was developed, and a plausible formation mechanism was proposed.

Background and Objective: Baicalin is a flavonoid compound purified from the medicinal plant, Scutellaria baicalensis Georgi, and has been reported to possess anti-inflammatory and antioxidant activities. The purpose of this study was to test the ability of baicalin to influence the progression of experimental periodontitis in rats, as well as the expression of cyclooxygenase-2 and inducible nitric oxide synthase. Material and Methods: Adult male Sprague–Dawley rats were subjected to placement of a nylon thread around the bilateral lower first molars and killed after 7 d. Baicalin (50, 100 or 200 mg/kg) was supplied to the animals by oral gavage, starting 1 d before the induction of periodontitis. The ligature group consisted of rats subjected to periodontitis and receiving vehicle (0.5% carboxymethylcellulose) alone. The alveolar bone loss and the area fraction occupied by collagen fibers were assessed. The expression of cyclooxygenase-2 and inducible nitric oxide synthase protein in the gingiva were detected by immunohistochemistry and western blotting. Results: Baicalin-treated groups presented with lower alveolar bone loss than that of the ligature group, reaching statistical significance at the dose of 200 mg/kg (p = 0.009). The area fraction of collagen fibers was significantly higher in the baicalin (200 mg/kg)-treated group than in the ligature group (p = 0.047). Baicalin treatment significantly down-regulated the protein expression for cyclooxygenase-2 (p = 0.000) and inducible nitric oxide synthase (p = 0.003), compared with the ligature group. Conclusion: Baicalin protects against tissue damage in ligature-induced periodontitis in rats, which might be mediated, in part, by its inhibitory effect on the expression of cyclooxygenase-2 and inducible nitric oxide synthase. These activities could support the continued investigation of baicalin as a potential therapeutic agent in periodontal disease.

Matrix metalloproteinases (MMPs), produced by both infiltrating and resident cells of the periodontium, play important roles in physiologic and pathologic events. Both interleukin-1 beta and extracellular MMP inducer can stimulate the expression of MMPs, which in turn leads to breakdown of the periodontium. However, it is currently unknown whether interleukin-1 beta up-regulates MMPs through stimulating the expression of extracellular MMP inducer. The aims of this study were to investigate the effect of interleukin-1 beta on the expression of MMP-1, MMP-2 and extracellular MMP inducer in human periodontal ligament cells and to evaluate whether the regulation of MMP-1 and MMP-2 by this cytokine occurred through an effect on extracellular MMP inducer expression.Cultured human periodontal ligament cells were treated with varying concentrations (0.01-10 ng/mL) of interleukin-1 beta at for 6, 12 and 24 h. Reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, gelatin zymography and western blotting were performed to measure the mRNA and protein levels of MMP-1, MMP-2 and extracellular MMP inducer.Basal levels of mRNA and protein for MMP-1, MMP-2 and extracellular MMP inducer were detected in untreated human periodontal ligament cells. Interleukin-1 beta significantly up-regulated the expression of MMP-1 and MMP-2 mRNA and protein (p0.05); however, the levels of mRNA and protein for extracellular MMP inducer were not significantly different (p0.05). In the culture medium, the concentration of MMP-1 was also increased significantly, but the concentration of MMP-1 was not related to the concentration of extracellular MMP inducer (R(2) = 0.2538, p0.05).Interleukin-1 beta up-regulated the levels of MMP-1 and MMP-2, but it did not alter the expression of extracellular MMP inducer. Expression of MMP-1 and MMP-2 might be elevated by interleukin-1 beta and extracellular MMP inducer via two different signal pathways.

Background and objective: CypA is able to regulate inflammatory responses and MMPs production via interaction with its cell surface receptor, EMMPRIN. This study aimed to address the possible association of CypA with pathological inflammation and destruction of periodontal tissues, and whether CypA-EMMPRIN interaction exists in periodontitis. Materials and methods: Experimental periodontitis was induced by ligation according to our previous method. Histological and radiographic examinations were performed. Western blot was used to detect CypA and EMMPRIN expressions in gingival tissues. Immunohistochemistry was applied for CypA, EMMPRIN, MMP-1, MMP-2, MMP-9, as well as cell markers of macrophage, lymphocyte and neutrophil. CypA expression, alveolar bone loss, and inflammatory infiltrations were quantified followed by correlation analyses. Results: Western blot revealed that CypA and EMMRPIN expressions were dramatically elevated in inflamed gingival tissues (ligature group) as compared to healthy gingival tissues (control group). The enhanced CypA and EMMPRIN expressions were highly consistent in cell localization on seriate sections. They were permanently co-localized in infiltrating macrophages and lymphocytes, as well as osteoclasts and osteoblasts in interradicular bone, but rarely expressed by infiltrating neutrophils. MMP-1, MMP-2, and MMP-9 expressions were also sharply increased in inflamed gingiva. MMP-2 and MMP-9 were mainly over-expressed by macrophages, while MMP-1 wasmore » over-produced by fibroblasts and infiltrating cells. The number of CypA-positive cells was strongly correlated with the ACJ-AC distance (r = 0.839, p = 0.000), the number of macrophages (r = 0.972, p = 0.000), and the number of lymphocytes (r = 0.951, p = 0.000). Conclusion: CypA is associated with the inflammatory infiltration and alveolar bone destruction of periodontitis. CypA-EMMPRIN interaction may exist in these pathological processes.« less

Periodontitis are characterized by the destruction of the extracellular matrix (ECM) of periodontal tissues. Matrix metalloproteinases (MMPs) play an important role in the degradation of ECM. But until now, it is not clear about the regulation of MMPs expression level in periodontitis. EMMPRIN is a 58 kDa, highly glycosylated, transmembrane molecule belonging to the immunoglobin superfamily, which interacts with fibroblasts to stimulate the expression of MMPs. It is logical to postulate that EMMPRIN may play a critical role in the regulation of MMPs participating the destruction of periodontal ECM in periodontitis. The hypothesis will provide the brand-new direction that we may prevent and treat the periodontitis by regulating the expression of EMMPRIN in host aspect.