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Numerous studies have demonstrated an association between periodontitis and oral squamous cell carcinoma (OSCC), and periodontal pathogens such as Treponema denticola are implicated in the pathogenesis of OSCC. Previous studies have mainly focused on T. denticola surface proteins—for example, chymotrypsin-like proteinase, which was detected in the majority of orodigestive tumor tissues. T. denticola may influence the development of OSCC. Nevertheless, the potential direct regulatory mechanism of T. denticola in OSCC is still unclear. Therefore, this study aimed to explore the direct effect of T. denticola on OSCC cell proliferation and elucidate potential mechanisms of T. denticola in contributing to cell proliferation. A series of in vitro experiments (e.g., CCK-8, EdU, flow cytometry) were performed to explore the effect of T. denticola on cell proliferation, cell cycle, and apoptosis. Mice experiments were performed to explore the effect of T. denticola on tumor growth. Whole mRNA transcriptome sequencing and quantitative real-time polymerase chain reaction were performed to explore the intracellular signaling pathway. Our study found that T. denticola could invade Cal-27 cells and directly promote cell proliferation, regulate the cell cycle, and inhibit apoptosis. T. denticola could also promote the growth of OSCC tumors in mice, and it upregulated Ki67 expression. Regarding the mechanism, T. denticola could promote the development of OSCC by activating the TGF-β pathway. In conclusion, T. denticola could promote OSCC cell proliferation directly, and the mechanism was associated with intracellular TGF-β pathway activation.

Dental caries is prevalent, and secondary caries causes restoration failures. This article reviews recent studies on developing a new generation of bioactive resins with anticaries properties. Extensive effects were made to develop new antimicrobial composites, bonding agents, and other resins containing quaternary ammonium methacrylates to suppress plaque buildup and bacterial acid production. The effects of alkyl chain length and charge density and the antimicrobial mechanisms for chlorhexidine, nano-silver, quaternary ammonium methacrylates, and protein-repellent agents were discussed. Synergistic effects of contact-killing and protein-repellent properties were shown to yield the greatest biofilm-inhibition effects. The combination of antimicrobial, protein-repellent, and calcium phosphate nanoparticle remineralization was suggested to provide maximal anticaries effects. In addition, for use orally, cytotoxicity and biocompatibility were important considerations for the new bioactive materials. Furthermore, rather than kill all bacteria, it would be more desirable to modulate the oral biofilm compositions via bioactive resins to suppress cariogenic/pathogenic species and promote benign species. For widespread clinical use of the new antimicrobial and therapeutic materials, whether they would induce bacterial drug resistance needs to be determined, which requires further study. Nonetheless, the new generation of bioactive anticaries resins with therapeutic and biofilm acid-inhibiting properties has the potential to substantially benefit oral health.

Carbon nanofibers (CNFs) with different content of surface functional groups which are carboxyl groups (CNF–OX), carbonyl groups (CNF–CO) and hydroxyl groups (CNF–OH) and nitrogen-containing groups (CNF–ON) are synthesized, and their electrocatalytic activities toward oxygen reduction reaction (ORR) in alkaline solution are investigated. The result of X-ray photoelectron spectroscopy (XPS) characterization indicates that a higher concentration of carboxyl groups, carbonyl groups and hydroxyl groups are imported onto the CNF–OX, CNF–CO and CNF–OH, respectively. Cyclic voltammetry shows that both the oxygen- and nitrogen-containing groups can improve the electrocatalytic activity of CNFs for ORR. The CNF–ON/GC electrode, which has nitrogen-containing groups, exhibits the highest current density of ORR. Rotating disk electrode (RDE) characterization shows that the oxygen reduction on CNF–ON/GC electrode proceeds almost entirely through the four-electron reduction pathway, the CNF–OX/GC, CNF–CO/GC and CNF–OH/GC electrodes proceed a two-electron reduction pathway at low potentials (−0.2 V to −0.6 V) followed by a gradual four-electron reduction pathway at more negative potentials, while the untreated carbon nanofiber (CNF–P/GC) electrode proceeds predominantly by a two-electron reduction pathway within the whole range of potential studied.

Pt nanoparticles supported on the acid-treated carbon nanofiber (CNF-OX) and LiAlH4-treated carbon nanofiber (CNF-OH) are synthesized via ethylene glycol reduction method. The nature of oxygen-containing surface groups on the CNF-OX and CNF-OH is investigated by potentiometric titration and XPS characterization. Titration of the support materials shows that LiAlH4 can effectively convert the carboxylic acid groups (from 0.21 mmol g−1 to 0.06 mmol g−1) to hydroxyl groups (from 0.09 mmol g−1 to 0.17 mmol g−1), which is agreed well with the results of XPS characterization. High resolution transmission electron microscopy (HRTEM) characterization shows that the Pt nanoparticles are highly dispersed on the two modified CNFs, and the Pt nanoparticles supported on the CNF-OH have a smaller particle size and a more uniform particle size distribution. Rotating disk electrode (RDE) analysis reveals that Pt/CNF-OH exhibits a better activity for ORR than Pt/CNF-OX, and this may be associated with the smaller particle size and better dispersion of Pt nanoparticles on the CNF-OH.

The anti-cariogenic properties of tea have been suggested for decades. Tea polyphenols, especially epigallocatechin gallate (EGCG), have been shown to inhibit dental plaque accumulation, but the exact mechanisms are not clear at present. We hypothesise that EGCG suppresses gtf genes in Streptococcus mutans at the transcriptional level disrupting the initial attachment of S. mutans and thus the formation of mature biofilms.In this study, the effect of EGCG on the sucrose-dependent initial attachment of S. mutans UA159 in a chemically defined medium was monitored over 4 h using a chamber slide model. The effects of EGCG on the aggregation and gtf B, C, D gene expression of S. mutans UA159 were also examined.It was found that EGCG (7.8-31.25 μg/ml) exhibited dose-dependent inhibition of the initial attachment of S. mutans UA159. EGCG did not induce cellular aggregation of S. mutans UA159 at concentrations less than 78.125 μg/ml. Analysis of data obtained from real-time PCR showed that EGCG at sub-MIC level (15.6 μg/ml) significantly suppressed the gtf B, C, D genes of S. mutans UA159 compared with the non-treated control (p0.05).These findings suggest that EGCG may represent a novel, natural anti-plaque agent that inhibits the specific genes associated with bacterial biofilm formation without necessarily affecting the growth of oral bacteria.

Secondary caries is a frequent reason for restoration failure, resulting from acidogenic bacteria and their biofilms. The objectives of this study were to: (1) develop a novel nanocomposite containing nanoparticles of amorphous calcium phosphate (NACP) and quaternary ammonium dimethacrylate (QADM); and (2) investigate its mechanical and antibacterial durability. A spray-drying technique yielded NACP with particle size of 116 nm. The nanocomposite contained NACP and reinforcement glass fillers, with QADM in the resin. Two commercial composites were tested as controls. Composites were inoculated with Streptococcus mutans. After 180-day water-aging, NACP+QADM nanocomposite had flexural strength and elastic modulus matching those of commercial controls (p > 0.1). NACP+QADM nanocomposite reduced the biofilm colony-forming units (CFU) by 3-fold, compared with commercial composites (p < 0.05). Metabolic activity and lactic acid production of biofilms on NACP+QADM were much less than those on commercial composites (p < 0.05). The antibacterial properties of NACP+QADM were maintained after water-aging for 30, 90, and 180 d (p > 0.05). In conclusion, the novel NACP-QADM nanocomposite greatly decreased biofilm metabolic activity, CFU, and lactic acid, while matching the load-bearing capability of commercial composites without antibacterial properties. The NACP-QADM nanocomposite with strong and durable antibacterial properties, together with its previously reported Ca-PO4 release capability, may render it useful for caries-inhibiting restorations.

In the present study, a kind of solid polymer electrolyte (SPE) based on poly(vinylidene difluoride-co-hexafluoropropylene)/poly(methyl methacrylate) blends was prepared by a casting method to solve the safety problem of lithium secondary batteries. Owing to being plasticized with a room temperature ionic liquid, N-butyl-N′-methyl-imidiazolium hexafluorophosphate, the obtained SPE shows a thermal decomposition temperature over 300°C and an ionic conductivity close to 10−3 S cm−1. The SPE-3 sample, in which the weight of two polymers is equivalent, possesses an ionic conductivity of 0.45 × 10−3 S cm−1 at 25°C and presents an electrochemical window of 4.43 V. The ionic conductivity of the SPE-3 is as high as 1.73 × 10−3 S cm−1 at 75°C approaching to that of liquid electrolyte. The electrochemical performances of the Li/LiFePO4 cells confirmed its feasibility in lithium secondary batteries.

UV laser irradiation induced structural modification in amorphous silica was characterized using Fourier transform infrared and X-ray induced photoelectron spectroscopy. Laser irradiation experiment was conducted using a 3 ω , 355 nm beam from a pulsed Nd-YAG laser with pulse length of 6.8 ns and laser repetition rate of 1 Hz at ambient conditions. The examined laser fluence was controlled at a relatively low level, ranging from 0 to 4 J/cm 2 . The IR spectra revealed that the vibration frequency of the rocking mode of Si O Si covalent bond shifted to lower wave number, while the bending mode and asymmetric stretching mode of Si O Si covalent bond shifted to higher frequency. This result suggested that the length of Si O Si covalent bond was decreased, the bond angle was increased and the irradiation modified material was densified after irradiation. The high resolution XPS spectra of Si 2p and O 1s illustrated the chemical shift of silicon and oxygen ions after irradiation. The XPS chemical shift of the Si 2p peak about 1.1 eV revealed the existence of low valence silicon ions Si 3+ species in silica glass after irradiation. The chemical shift of the O 1s peak about 0.9 eV illustrated the emergence of non-bridging oxygen ions during laser irradiation. The deconvoluted peak area and FWHM value of low valence silicon ions and non-bridging oxygen ions all exhibited exponentially growth as the linearly elevation of laser fluence. UV laser-induced photolysis of Si O covalent bond was suggested to be responsible for the formation and increase of low valence silicon ions and non-bridging oxygen ions. These FT-IR and XPS data revealed that short range structural modifications were important structure alterations in silica glass before the emergence of distinct and large size damage crater.

In this study, we prepare a kind of solid polymer electrolyte (SPE) based on N-ethyl-N′-methyl imidazolium tetrafluoroborate (EMIBF4), LiBF4 and poly(vinylidene difluoride-co-hexafluoropropylene) [P(VdF-HFP)] copolymer. The resultant SPE displays high thermal stability above 300 °C and high room temperature ionic conductivity near to 10−3 S cm−1. Its electrochemical properties are improved with incorporation of a zwitterionic salt 1-(1-methyl-3-imidazolium)propane-3-sulfonate (MIm3S). When the SPE contains 1.0 wt% of the MIm3S, it has a high ionic conductivity of 1.57 × 10−3 S cm−1 at room temperature, the maximum lithium ions transference number of 0.36 and the minimum apparent activation energy for ions transportation of 30.9 kJ mol−1. The charge–discharge performance of a Li4Ti5O12/SPE/LiCoO2 cell indicates the potential application of the as-prepared SPE in lithium ion batteries.

A macaroni-like Li 1.2 V 3 O 8 nanomaterial was directly prepared through a facile solution route using β-cyclodextrin (β-CD) as a template reagent. Its crystal structure was determined by the X-ray diffraction (XRD) pattern. From the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) micrographs, we observed that the as-prepared Li 1.2 V 3 O 8 material consisted of the aggregated macaroni-like nanoparticles and showed a porous structure. The electrochemical properties of the as-prepared Li 1.2 V 3 O 8 in 1.0 M Li 2 SO 4 aqueous electrolyte were studied through cyclic voltammograms and charge–discharge measurements. The results revealed that the as-prepared Li 1.2 V 3 O 8 could deliver the initial specific capacities of 189, 140, and 101 mAh g −1 at 0.1, 0.5, and 1.0 C, respectively. It suggests that the as-prepared Li 1.2 V 3 O 8 should have an attractive future to be applied in aqueous rechargeable lithium battery (ARLB).

A foaming process was used to prepare porous polymer membranes (PPMs) based on poly(vinylidene diflouride-co-hexafluoropropylene) copolymer for lithium ion batteries. In this simple process, urea, the foaming agent, was decomposed into gases and was removed at an elevated temperature to get the porous structure within the polymer matrix. When the weight ratio of urea to P(VDF-HFP) is 5:6, the PPM presents the highest porosity, 70.2%, and the prepared gelled polymer electrolyte shows an ionic conductivity up to 1.43 × 10 −3 S cm −1 at room temperature. This provides another way to prepare gelled polymer electrolytes easily for application in rechargeable lithium batteries.

A kind of porous nanocomposite polymer membranes (NCPMs) based on poly(vinylidene difluoride-co-hexafluoropropylene) (P(VdF-HFP)) incorporated with different amounts of TiO 2 nanoparticles from in situ hydrolysis of Ti(OC 4 H 9 ) 4 was prepared by a non-solvent induced phase separation (NIPS) technology. The SEM micrographs reveal that a porous structure exists in the NCPMs, which changes with the incorporated amount of TiO 2 . The NCPMs incorporated with 9.0 wt.% of mass fraction of TiO 2 possess the highest porosity, 67.3%, and appear as flexile fracture with an elongation ratio, 74.4%. At this content, the ionic conductivity of the NCPE is up to 0.94 × 10 −3 S cm −1 at room temperature and the activation energy for ions transport reaches the lowest, 18.71 kJ mol −1 . It is of great potential application in lithium ion batteries.

A lotus root-like porous nanocomposite polymer electrolyte (NCPE) based on poly(vinylidene difluoride-co-hexafluoropropylene) [P(VDF-HFP)] copolymer and TiO2 nanoparticles was easily prepared by a non-solvent induced phase separation (NIPS) process. The formation mechanism of the lotus root-like porous structure is explained by a qualitative ternary phase diagram. The resulting NCPE had a high ionic conductivity up to 1.21 × 10−3 S cm−1 at room temperature, and exhibited a high electrochemical stability potential of 5.52 V (vs. Li/Li+), lithium ion transference number of 0.65 and 22.89 kJ mol−1 for the apparent activation energy for transportation of ions. It is of great potential application in polymer lithium ion batteries. Keywords: Lotus root, Nanocomposite polymer, Porous membranes, P(VDF-HFP), Phase separation

Peptides containing 8 repeats of aspartate-serine-serine (8DSS) have been shown to promote the nucleation of calcium phosphate from solution into human enamel. Here we tested the ability of 8DSS to promote the remineralization of demineralized enamel in an in vitro model of artificial early enamel caries. Initial caries lesions were created in bovine enamel blocks, which were then subjected to 12 d of pH cycling in the presence of 25 µM 8DSS, 1 g/L NaF (positive control) or buffer alone (negative control). Absorption of 8DSS was verified by X-ray photoelectron spectroscopy. Mineral loss, lesion depth, and mineral content at the surface layer and at different depths of the lesion body were analyzed before and after pH cycling by polarized light microscopy and transverse microradiography. Mineral loss after pH cycling was significantly lower in the 8DSS samples than in the buffer-only samples, and lesions in the 8DSS samples were significantly less deep. Samples treated with 8DSS showed significantly higher mineral content than buffer-only samples in the region extending from the surface layer (30 µm) to the average lesion depth (110 µm). No significant differences were found between the samples treated with 8DSS and those treated with NaF. These findings suggest that 8DSS has the potential to promote remineralization of demineralized enamel.

Chronic fatigue syndrome, which can occur after acute infection and last for years, is characterized by severe and persistent fatigue. Others have reported decreases in mouse running activity following infection and have suggested this may provide an animal model for studying chronic fatigue. Voluntary running is a highly motivated activity in mice, which will often run 5–7 mi/day in our laboratory. Following 2 weeks of acclimation to running wheels with food and water available ad lib, female BALB/c mice received 0.2-mL tail vein injections of killed Brucella abortus (BA) or saline vehicle. Subsequently the effects on voluntary running and grooming behavior were determined. Injection of BA caused an immediate large decrease in running and a lack of grooming. Vehicle injections produced no changes in behavior. After the first several days of reduced running behavior, levels of running and grooming slowly returned back to normal over the next 2–4 weeks, with substantial individual differences in the rate of recovery. The pattern of running during recovery was intriguing in that BA mice first ran at normal levels just after the lights went out, but they stopped after only 1–2 h. As recovery proceeded, they gradually increased the duration of the running bout during the night. Because this model uses voluntary exertion and the ability to run for longer periods of time characterizes recovery, the model may be a good one for studying the biologic underpinnings of chronic fatigue.

Die Operation des kleinen hepatozellularen Karzinoms (HCC) hat eine neue Phase in der Chirurgie dieser Tumorart eingeleitet, welche gekennzeichnet ist durch hohere Resektabilitat, niedrigere Operation

Streptococcus mutans , the primary etiologic agent of dental caries, possesses a series of virulence factors associated with its cariogenicity. Alternatives to traditional antimicrobial treatment, agents selectively inhibiting the virulence factors without necessarily suppressing the resident oral species, are promising. The anticariogenic properties of tea have been suggested in experimental animals and humans. Tea polyphenols, especially epigallocatechin gallate (EGCg), have been shown to inhibit the growth and glucosyltransferases activity of S. mutans . However, their effects on biofilm and cariogenic virulence factors of oral streptococci other than glucosyltransferases have not been well documented. In this study, we investigated the biological effect of EGCg on the virulence factors of S. mutans associated with its acidogenicity and acidurity. The antimicrobial effects of EGCg on S. mutans biofilm grown in chemically defined medium were also examined. EGCg inhibited growth of S. mutans planktonic cells at an MIC of 31.25 μg/ml and a minimal bactericidal concentration (MBC) of 62.5 μg/ml. EGCg also inhibited S. mutans biofilm formation at 15.6 μg/ml (minimum concentration that showed at least 90% inhibition of biofilm formation) and reduced viability of the preformed biofilm at 625 μg/ml (sessile MIC 80 ). EGCg at sub-MIC levels inhibited acidogenicity and acidurity of S. mutans cells. Analysis of the data obtained from real-time PCR showed that EGCg significantly suppressed the ldh , eno , atpD , and aguD genes of S. mutans UA159. Inhibition of the enzymatic activity of F 1 F o -ATPase and lactate dehydrogenase was also noted (50% inhibitory concentration between 15.6 and 31.25 μg/ml). These findings suggest that EGCg is a natural anticariogenic agent in that it exhibits antimicrobial activity against S. mutans and suppresses the specific virulence factors associated with its cariogenicity.

Epigallocatechin gallate (EGCg), the main antimicrobial tea catechin, has been reported to inhibit growth and virulence factors of oral pathogens in vitro. Although the mechanism is unclear, the potential of EGCg in reducing halitosis caused by volatile sulfur compounds (VSCs) has been suggested. This study tested the hypothesis that EGCg reduces VSCs by suppressing mgl, the gene encoding L-methionine-α-deamino-γ-mercaptomethane-lyase, responsible for methyl mercaptan (CH3SH) production by oral anaerobes. In this study, the effect of EGCg on in vitro growth, CH3SH production, and mgl gene expression in P. gingivalis W83 was investigated. EGCg inhibited growth of P. gingivalis W83 (MIC = 97.5 µg/mL) and was bactericidal (MBC = 187.5 µg/mL). At sub-MIC levels, EGCg inhibited CH3SH production, and mgl mRNA and protein expression (p < 0.05). We conclude that EGCg may represent a natural and alternative agent to the antimicrobial chemicals currently available for halitosis control.

A computer model (based on the contomintegral technique) is used to predict the scattering panuneten of the microsvip notched-sectorial power divider. The insextion of the notch featwe in the simple sectorial structure introduces an addjltional design parameter that may be used to selectively control some of the component's scattering parameters.

A low frequency pushing wide frequency tuning range radio frequency (RF) voltage-controlled oscillator (VCO) in 0.35 /spl mu/m standard CMOS process for wireless applications is presented. It is different from all conventional designs primarily in the way it is biased. The measurement results show that the proposed structure reduces the frequency pushing to 0.55%/V and increases the frequency tuning range to 516 MHz. It provides a minimum figure of merit for oscillators (FOM) of about -180 dBc/Hz following the optimization method. The main contributions include: (a) the proposed VCO structure, (b) the FOM optimization method and (c) the silicon results.

The stability of superconducting properties of epitaxial Tl2Ba2CaCu2O8 thin films in water has been investigated at room temperature. The measurements of Tc, Jc and XRD θ–θ scans proved that the superconductivity of the completely crystalline film was very stable in water at room temperature. If the film is mixed with amorphous inclusion of BaO and CaO, it can be corroded in water. If the film is polluted by photoresist, silver dag, indium or silver, it is rapidly corroded in water.

A new large signal model of GaAs MESFET is proposed. A commercial packaged high power MESFET (Fujitsu FLC103WG) is adopted for the extraction. Both the hot and cold condition measurements and the pulsed I/V measurement are performed to derive the model. A simple single-stage class-AB amplifier is subsequently built so as to verify the derived model. The simulation and measurement results of the intermodulation distortion of this amplifier are compared.

The characteristic of a novel rectangular air-filled stacked patch with an offset L-shaped probe are experimentally investigated. The top patch and lower U-slot patch are all supported by thin basswoods at the four corners and the height for the lower U-slot patch is approximately 10% of the designed wavelength. An impedance bandwidth of 44.4% and average gain of approximately 15 dB can be achieved.

The temperature distribution of multiple heat-sources in materials with temperature dependent thermal conductivity has been derived. The method involves the application of the Kirchhoff transformation, the method of images, the adaptive method and the inverse Kirchhoff transformation. The agreement between this method and the accurate direct method is within 1%, and the computation time is much less than the traditional method.

Because of recent interest in the effects of physical exercise on immunologic function, we decided to use state-of-the-art methods to evaluate cytokines in the peripheral blood leukocytes (PBLs) of 7 men before and after a maximal treadmill stress test. Change in cytokine gene expression was quantified from PBLs using a reverse transcriptase polymerase chain reaction assay (RT-PCR). In contrast to reports on serum levels or using in vitro testing, direct gene expression of TNF-alpha decreased after the stress test (p < 0.008). However, the 47% decrease was relatively small and of questionable biological significance. Levels of IL-1a, IL-1b, IL-2, IL-4, IL-6, IL-10, and INF-gamma did not change.

The contour-integral procedure is used to analyse the microstrip sectorial n-way power divider. The principal advantage of the present approach is that the resulting model is able to handle arbitrary sector angles, in contrast to the Green's function approach used by other researchers, which is valid only if the sector angle is a submultiple of Φ. Computational and experimental tests indicate that numerical accuracies of better than ± 1% are obtainable from the present model.