Surface Topography of Titanium Affects Their Osteogenic Potential through DNA Methylation.

It is widely accepted that sandblasted/large-grit/acid-etched (SLA) surfaces of titanium (Ti) have a higher osteogenic potential than machined ones. However, most studies focused on differential gene expression without elucidating the underlying mechanism for this difference. The aim of this study was to evaluate how the surface roughness of dental Ti implants affects their osteogenic potential. Mouse preosteoblast MC3T3-E1 cells were seeded on machined and SLA Ti discs. The cellular activities of the discs were analyzed using confocal laser scanning microscopy, proliferation assays, and real-time polymerase chain reaction (PCR). DNA methylation was evaluated using a methylation-specific PCR. The cell morphology was slightly different between the two types of surfaces. While cellular proliferation was slightly greater on the machined surfaces, the osteogenic response of the SLA surfaces was superior, and they showed increased alkaline phosphatase (Alp) activity and higher bone marker gene expression levels (Type I collagen, Alp, and osteocalcin). The degree of DNA methylation on the Alp gene was lower on the SLA surfaces than on the machined surfaces. DNA methyltransferase inhibitor stimulated the Alp gene expression on the machined surfaces, similar to the SLA surfaces. The superior osteogenic potential of the SLA surfaces can be attributed to a different epigenetic landscape, specifically, the DNA methylation of Alp genes. This finding offers novel insights into epigenetics to supplement genetics and raises the possibility of using epidrugs as potential therapeutic targets to enhance osteogenesis on implant surfaces.

A peptide array-based serological protein kinase A activity assay and its application in cancer diagnosis.

Protein kinase A (PKA) plays a crucial role in several biological processes; however, there is no assay with sufficient sensitivity and specificity to determine serological PKA (sPKA) activity. Here we present an on-chip activity assay that employs cysteine-modified kemptide arrays to determine specific sPKA activity in human sera that eliminates the potential contributions of other kinases with a protein kinase peptide inhibitor. The sensitivity of the on-chip sPKA activity assay was greatly enhanced by Triton X-100, with a 0.01 U mL(-1) detection limit. sPKA activity was determined by subtracting nonspecific sPK activity from total sPK activity. Our assay provided greater sensitivity and specificity and more accurate area under the curve values for gastric cancer compared to the total sPK activity assay. sPKA activities in human sera from patients with hepatic (n = 30), gastric (n = 30), lung (n = 30), and colorectal (n = 30) cancers were significantly higher than those in controls (n = 30, p < 10(-4)), but no significant difference in sPKA activities between normal and inflammation groups was observed. These results demonstrate that the on-chip assay accurately measures sPKA activity in human sera and that the sPKA activity may be a potential biomarker for cancer diagnosis.

Antimicrobial activity of peptides derived from olive flounder lipopolysaccharide binding protein/bactericidal permeability-increasing protein (LBP/BPI).

We describe the antimicrobial function of peptides derived from the C-terminus of the olive flounder LBP BPI precursor protein. The investigated peptides, namely, ofLBP1N, ofLBP2A, ofLBP4N, ofLBP5A, and ofLBP6A, formed α-helical structures, showing significant antimicrobial activity against several Gram-negative bacteria, Gram-positive bacteria, and the yeast Candida albicans, but very limited hemolytic activities. The biological activities of these five analogs were evaluated against biomembranes or artificial membranes for the development of candidate therapeutic agents. Gel retardation studies revealed that peptides bound to DNA and inhibited migration on an agarose gel. In addition, we demonstrated that ofLBP6A inhibited polymerase chain reaction. These results suggested that the ofLBP-derived peptide bactericidal mechanism may be related to the interaction with intracellular components such as DNA or polymerase.

The worldwide patent landscape of dental implant technology.

In an aging society, quality of life improvement is emerging as an important issue, and as implants are accepted as the core of oral rehabilitation treatment, competition for leadership in developing related technologies is intensifying. In this trend, unlike what is evident in the literature, the patent landscape shows the status of industrial-based technology development. A database analysis of a total of 32,237 dental implant patents shows improvements in technology, diverse geographical characteristics, and new advances toward technological convergence in this field. Technologically, dental implant technology has shown a tendency to develop from conventional implant materials and surface treatment technologies to new material technologies making use of substances such as pure zirconium and tantalum or software technologies related to diagnosis and prognosis. Regionally, dental implant technology, which was developed mainly in Europe and the Unites States in the past, is growing explosively in East Asian countries accompanied by the recent growth of the Asian market. In summary, dental implant technology seems to be developing while trying to converge with various technological areas based on the local market environment. Therefore, it is necessary to develop a new dental implant material technology that is highly applicable to the development of hybrid information/communication technology and is suitable for a new manufacturing method. Our study may provide important information to help basic and translational researchers and their financial supporters set their research directions in advancing the development of dental implants.

Nanofibrous topography-driven altered responsiveness to Wnt5a mediates the three-dimensional polarization of odontoblasts.

Cell differentiation with the proper three-dimensional (3-D) structure is critical for cells to carry out their cellular functions in tissues. Odontoblasts derived from neural crest cells are elongated and polarized with the cell process, which is decisive for one directional tubular dentin formation. Here, we report that the fibrous topography of scaffolds directs odontoblast-lineage cells to differentiate to have the 3-D structure of odontoblasts through an altered responsiveness to Wnt family member 5A (Wnt5a). In a pulp-exposure animal model, the scaffolds with the nanofibrous topography supported the regeneration of tubular dentin with odontoblast processes. In cultures of pre-odontoblast cells, the nanofibrous topography heightened the cells on the z-axis. The cells on nanofibrous substrate (FIBER) formed stress fiber cytoskeletons on a conventional tissue culture plate (TCP). Differential activation of Cell division control protein 42 (Cdc42) on FIBER and Ras homolog family member A (RhoA) on TCP led to these differences. The signal from Wnt5a-Cdc42 in the cells on FIBER mediated the phosphorylation of JNK and the polarity growth signaling. Taken together, the nanofibrous topography of the scaffolds led to the 3-D structural differentiation of odontoblasts in vitro and in vivo, implying its application for dentin regeneration. Furthermore, the results on the altered activation of Cdc42 by Wnt5a on FIBER provide evidence that the topography of the scaffolds can cause a distinctive cell responsiveness to their micro-environments.

Comparative analyses of the venom components in the salivary gland transcriptomes and saliva proteomes of some heteropteran insects.

Salivary gland-specific transcriptomes of nine heteropteran insects with distinct feeding strategies (predaceous, hematophagous, and phytophagous) were analyzed and annotated to compare and identify the venom components as well as their expression profiles. The transcriptional abundance of venom genes was verified via quantitative real-time PCR. Hierarchical clustering of 30 representative differentially expressed venom genes from the nine heteropteran species revealed unique groups of salivary gland-specific genes depending on their feeding strategy. The commonly transcribed genes included a paralytic neurotoxin (arginine kinase), digestive enzymes (cathepsin and serine protease), an anti-inflammatory protein (cystatin), hexamerin, and an odorant binding protein. Both predaceous and hematophagous (bed bug) heteropteran species showed relatively higher transcription levels of genes encoding proteins involved in proteolysis and cytolysis, whereas phytophagous heteropterans exhibited little or no expression of these genes, but had a high expression of vitellogenin, a multifunctional allergen. Saliva proteomes from four representative species were also analyzed. All venom proteins identified via saliva proteome analysis were annotated using salivary gland transcriptome data. The proteomic expression profiles of venom proteins were in good agreement with the salivary gland-specific transcriptomic profiles. Our results indicate that profiling of the salivary gland transcriptome provides important information on the composition and evolutionary features of venoms depending on their feeding strategy.

Recent Advances of Therapeutic Targets for the Treatment of Periodontal Disease.

Periodontal disease is primarily associated with bacterial infection such as dental plaque. Dental plaque, an oral biofilm harboring a complex microbial community, can cause various inflammatory reactions in periodontal tissue. In many cases, the local bacterial invasion and host-mediated immune responses lead to severe alveolar bone destruction. To date, plaque control, non-surgical, and surgical interventions have been the conventional periodontal treatment modalities. Although adjuvant therapies including antibiotics or supplements have accompanied these procedures, their usage has been limited by antibiotic resistance, as well as their partial effectiveness. Therefore, new strategies are needed to control local inflammation in the periodontium and host immune responses. In recent years, target molecules that modulate microbial signaling mechanisms, host inflammatory substances, and bone immune responses have received considerable attention by researchers. In this review, we introduce three approaches that suggest a way forward for the development of new treatments for periodontal disease; (1) quorum quenching using quorum sensing inhibitors, (2) inflammasome targeting, and (3) use of FDA-approved anabolic agents, including Teriparatide and sclerostin antibody.

Patent landscape report on dental implants: A technical analysis.

BACKGROUND AND PURPOSE: Significant research and development (R&D) has been conducted to make the best dental implants while developing various patent applications and registrations. In this study, we evaluated the current status of patents on dental implants and identified the future direction of R&D progress. MATERIALS AND METHODS: A total of 29 711 patents related to dental implants were reviewed. These were published between 1909 and 2020 and retrieved from the Derwent Innovation patent database. The patents were grouped into three categories depending on the implant components: fixture, abutment, and artificial teeth. RESULTS: The category with most patents was "abutment," and the most cited patent was "screw-type dental implant anchor." Global patenting trends over the past 20 years showed that both applicants and applications increased in the early 2010s; however, these have since been on the decline. Currently, the United States holds the largest number of patents, and Nobel Biocare Holding AG is the top assignee. Technic maturation prediction analysis showed that the current dental implant technology is in the "decline stage." CONCLUSION: Trend analysis of the dental implant patent indicates the main contributors of development are profit-oriented companies. Recent reduction in the number of new patent applications suggests the technology is in the mature declining stage. The emergence of new materials or technologies that may close the gap in clinical unmet needs would reverse the trend.

Current advances of epigenetics in periodontology from ENCODE project: a review and future perspectives.

BACKGROUND: The Encyclopedia of DNA Elements (ENCODE) project has advanced our knowledge of the functional elements in the genome and epigenome. The aim of this article was to provide the comprehension about current research trends from ENCODE project and establish the link between epigenetics and periodontal diseases based on epigenome studies and seek the future direction. MAIN BODY: Global epigenome research projects have emphasized the importance of epigenetic research for understanding human health and disease, and current international consortia show an improved interest in the importance of oral health with systemic health. The epigenetic studies in dental field have been mainly conducted in periodontology and have focused on DNA methylation analysis. Advances in sequencing technology have broadened the target for epigenetic studies from specific genes to genome-wide analyses. CONCLUSIONS: In line with global research trends, further extended and advanced epigenetic studies would provide crucial information for the realization of comprehensive dental medicine and expand the scope of ongoing large-scale research projects.

Increased intestinal macromolecular permeability and urine nitrite excretion associated with liver cirrhosis with ascites.

AIM: To determine intestinal permeability, the serum tumor necrosis factor (TNF)-alpha level and urine nitric oxide (NO) metabolites are altered in liver cirrhosis (LC) with or without ascites. METHODS: Fifty-three patients with LC and 26 healthy control subjects were enrolled in the study. The intestinal permeability value is expressed as the percentage of polyethylene glycol (PEG) 400 and 3350 retrieval in 8-h urine samples as determined by high performance liquid chromatography. Serum TNF-alpha concentrations and urine NO metabolites were determined using an enzyme-linked immunosorbent assay (ELISA) and Greiss reaction method, respectively. RESULTS: The intestinal permeability index was significantly higher in patients with LC with ascites than in healthy control subjects or patients with LC without ascites (0.88 +/- 0.12 vs 0.52 +/- 0.05 or 0.53 +/- 0.03, P < 0.05) and correlated with urine nitrite excretion (r = 0.98). Interestingly, the serum TNF-alpha concentration was significantly higher in LC without ascites than in control subjects or in LC with ascites (198.9 +/- 55.8 pg/mL vs 40.9 +/- 12.3 pg/mL or 32.1 +/- 13.3 pg/mL, P < 0.05). Urine nitrite excretion was significantly higher in LC with ascites than in the control subjects or in LC without ascites (1170.9 +/- 28.7 micromol/L vs 903.1 +/- 55.1 micromol/L or 956.7 +/- 47.7 micromol/L, P < 0.05). CONCLUSION: Increased intestinal macromolecular permeability and NO is probably of importance in the pathophysiology and progression of LC with ascites, but the serum TNF-alpha concentration was not related to LC with ascites.

Low-power and low-drug-dose photodynamic chemotherapy via the breakdown of tumor-targeted micelles by reactive oxygen species.

Tumor-targeted delivery of anticancer agents using nanocarriers has been explored to increase the therapeutic index of cancer chemotherapy. However, only a few nanocarriers are clinically available because the physiological complexity often compromises their ability to target, penetrate, and control the release of drugs. Here, we report a method which dramatically increases in vivo therapeutic drug efficacy levels through the photodynamic degradation of tumor-targeted nanocarriers. Folate-decorated poly(ethylene glycol)-polythioketal micelles are prepared to encapsulate paclitaxel and porphyrins. Photo-excitation generates reactive oxygen species within the micelles to cleave the polythioketal backbone efficiently and facilitate drug release only at the illuminated tumor site. Intravenous injection of a murine xenograft model with a low dose of paclitaxel within the micelles, one-milligram drug per kg (mouse), corresponding to an amount less than that of Taxol by one order of magnitude, induces dramatic tumor regression without any acute systemic inflammation responses or organ toxicity under low-power irradiation (55 mW cm-2) at 650 nm.

Retroperitoneoscopic assisted single-site pyeloplasty using EZ access in children: Comparison with open dismembered pyeloplasty.

PURPOSE: The aim of this study was to compare the results of the retroperitoneoscopic assisted pyeloplasty (RASP) using EZ access (silicone rubber cap) with open dismembered pyeloplasty (ODP) in children. METHODS: A retrospective review was performed of patients treated for ureteropelvic junction (UPJ) obstruction with either RASP or ODP from 2010 to 2015. For patients with RASP, two 5-mm trocars were placed in the EZ access. The UPJ was dissected retroperitoneoscopically and dismembered pyeloplasty was performed extracorporeally. Patient demographics and operative outcomes were compared between the groups. RESULTS: A total of 50 children were included, with 25 RASP and 25 ODP. Mean patient age was 49months in the RASP group and 53months in the ODP group. Perioperative outcomes, including operative time (185 vs 188min) and postoperative hospital stay (2.0 vs 2.2days), were similar between the two groups. Mean skin scar length (17 vs 34mm) was significantly smaller in the RASP group. The postoperative success rate (96% vs 100%) was not significantly different between the groups. CONCLUSIONS: The RASP represents a safe and effective single-site procedure in children. This procedure significantly reduces the skin scar length and has equivalent surgical outcomes to ODP. THE TYPE OF STUDY: Retrospective comparative study. LEVELS OF EVIDENCE: III.

Fibroin particle-supported cationic lipid layers for highly efficient intracellular protein delivery.

Directly delivering therapeutic proteins into cells has promise as an intervention without side effects for protein deficiencies caused by genetic defects. However, as negatively charged macromolecules, proteins require carriers for achieving cellular uptake and maintaining their activity in the cytoplasm. The biodegradable natural polymer silk fibroin has demonstrated outstanding advantages as a protein drug scaffold in vitro and in vivo, but its usage has been limited in the extracellular space because of its negatively charged character. Here, we present an intracellular protein delivery system based on fibroin particles coated with cationic lipid layers, denoted as Fibroplex, the surface charge of which can be modulated. Fibroplex showed higher delivery efficiency than conventional delivery methods as well as long-term cargo release in the cytoplasm without toxicity. Furthermore, in vivo experiments showed that Fibroplex efficiently delivered tyrosinase and horseradish peroxidase, which led to hyper-pigmentation and tumor regression, respectively, suggesting its potential for therapeutic protein applications in hereditary diseases or cancer.

Effects of the polarizability and packing density of transparent oxide films on water vapor permeation.

The tin oxide and silicon oxide films have been deposited on polycarbonate substrates as gas barrier films, using a thermal evaporation and ion beam assisted deposition process. The oxide films deposited by ion beam assisted deposition show a much lower water vapor transmission rate than those by thermal evaporation. The tin oxide films show a similar water vapor transmission rate to the silicon oxide films in thermal evaporation but a lower water vapor transmission rate in IBAD. These results are related to the fact that the permeation of water vapor with a large dipole moment is affected by the chemistry of oxides and the packing density of the oxide films. The permeation mechanism of water vapor through the oxide films is discussed in terms of the chemical interaction with water vapor and the microstructure of the oxide films. The chemical interaction of water vapor with oxide films has been investigated by the refractive index from ellipsometry and the OH group peak from X-ray photoelectron spectroscopy, and the microstructure of the composite oxide films was characterized using atomic force microscopy and a transmission electron microscope. The activation energy for water vapor permeation through the oxide films has also been measured in relation to the permeation mechanism of water vapor. The diffusivity of water vapor for the tin oxide films has been calculated from the time lag plot, and its implications are discussed.

Antibacterial Nanofibrous Mats Composed of Eudragit for pH-Dependent Dissolution.

A pH-responsive nanofibrous mesh was prepared for the controlled release of antibiotics in response to pH changes. Eudragit EPO (EPO) and Eudragit L100 (L100) were injected through inner and outer needle and simultaneously electrospun through coaxial nozzles composed of inner and outer needles. Various amounts of EPO and L100 were coejected with tetracycline through the needle and simultaneously electrospun to the fibrous meshes. The mass erosion rates of the meshes at pH 6.0 gradually decreased as the amounts of EPO increased, whereas those at pH 2.0 showed negligible differences; these differences were confirmed by scanning electron microscopy and monitoring the dry weight changes. At pH 6.0, the fibrous structures of the meshes rapidly disappeared compared to those under acidic conditions because Eudragit L100 is localized to the shell of the nanofiber during the electrospinning process. Both the pH changes and the blend ratio of the two polymers significantly affected the tetracycline release; tetracycline was rapidly released from the meshes at pH 6.0, whereas the release rates were attenuated at pH 2.0. Tetracycline was released faster from the mesh at higher blend ratios of EPO for both pH values. The electrostatic interaction between EPO and L100 is expected to yield different release profiles of tetracycline. Consequently, higher amounts of encapsulated drugs were released from the mesh at neutral pH and successfully inhibited bacterial growth.

Therapeutic applications of electrospun nanofibers for drug delivery systems.

Electrospun nanofiber drug delivery systems have been studied using various techniques. Herein, we describe the fabrication of a drug-incorporating nanofiber. Drugs, such as proteins, peptide, antibodies, and small molecule drugs, can be loaded within or on the surface of nanofibers according to their properties. Hydrophobic drugs are directly dissolved with a polymer in an organic solvent before electrospinning. However, it is preferred to surface-immobilize bioactive molecules on nanofibers by physical absorption or chemical conjugation. Especially, chemically surface-immobilized proteins on a nanofiber mesh stimulate cell differentiation and proliferation. Using a dual electrospinning nozzle to create nanofiber sheet layers, which are stacked on top of one another, the initial burst release is reduced compared with solid nanofibers because of the layers. Furthermore, hybridization of electrospun nanofibers with nanoparticles, microspheres, and hydrogels is indirect drug loading method into the nanofibers. It is also possible to produce multi-drug delivery systems with timed programmed release.

Pluronic@Fe3O4 nanoparticles with robust incorporation of doxorubicin by thermo-responsiveness.

Doxorubicin was physically incorporated in magnetic nanoparticles by thermo-responsive manners. Magnetic nanoparticles were prepared by oxidizing ferric ions in ammonium solution. Thiolated Pluronic was synthesized by sequential modification of terminal hydroxyl groups of Pluronic to amine groups and thiol groups. Magnetic nanoparticles composed of iron oxide were surface-modified with thiolated Pluronic at different molar ratios of iron to thiol groups. Pluronic decoration on the magnetic nanoparticles was characterized by elemental analysis and transmission electron microscopy. Elemental analysis results on carbon atoms in the magnetic nanoparticles showed that the degree of Pluronic decoration was proportional to the feed ratio of thiolated Pluronic to iron oxide. Doxorubicin was incorporated to the magnetic nanoparticles thermo-responsive manners; a mixture of hydrophobized doxorubicin and the magnetic nanoparticles was incubated at 4°C and the temperature was subsequently increased to 37°C for thermally induced structural changes of the decorated Pluronic moieties. Doxorubicin-incorporated magnetic nanoparticles showed dramatic modulations of size distributions according to temperature changes, which was dependent on the degree of Pluronic decoration. Loading efficiency of doxorubicin was significantly affected by the number of decorated Pluronic on the magnetic nanoparticles; the higher Pluronic moieties the nanoparticles had, the higher loading efficiency they showed. Release profiles of doxorubicin from the nanoparticles showed that doxorubicin was liberated from the nanoparticles in response to reducing conditions of the release medium. Anti-cancer activities of the doxorubicin-incorporated nanoparticles were determined by a MTT-based cytotoxicity assay against A549 cell lines. Compared to native doxorubicin, the doxorubicin incorporated magnetites showed attenuated cytotoxicities due to slow release of doxorubicin from the carriers. Thus, thermally induced incorporation of anti-cancer drugs can be a novel method for multifunctional magnetic nanoparticles with imaging and anti-cancer treatments.

High-throughput analysis of mumps virus and the virus-specific monoclonal antibody on the arrays of a cationic polyelectrolyte with a spectral SPR biosensor.

We investigated the potential use of a spectral surface plasmon resonance (SPR) biosensor in a high-throughput analysis of mumps virus and a mumps virus-specific mAb on the arrays of a cationic polyelectrolyte, poly(diallyldimethylammonium chloride) (PDDA). The PDDA surface was constructed by electrostatic adsorption of the polyelectrolyte onto a monolayer of 11-mercaptoundecanoic acid (MUA). Poly-L-lysine was also adsorbed onto the MUA monolayer and compared with the PDDA surface in the capacity of mumps virus immobilization. The PDDA surface showed a higher adsorption of mumps virus than the poly-L-lysine surface. The SPR signal caused by the virus binding onto the PDDA surface was proportional to the concentration of mumps virus from 0.5 x 10(5) to 14 x 10(5) pfu/mL. The surface structure of the virus arrays was visualized by atomic force microscopy. Then, a dose-dependent increase in the SPR signal was observed when various concentrations of the antimumps virus antibody in buffer or human serum were applied to the virus arrays, and their interaction was specific. Thus, it is likely that the spectral SPR biosensor based on the cationic polyelectrolyte surface may provide an efficient system for a high-throughput analysis of intact virus and serodiagnosis of infectious diseases.