OBJECTIVES: To assess the effect of glazing materials with different sealants on sealant surface roughness and surface hardness. METHODS: Ultraseal XT(TM) sealant (group 1) and 3M Concise(TM) sealant (group 2) were applied on the buccal surfaces of 26 bicuspid teeth per group. The buccal surface of each tooth was then divided into two half surfaces for 52 halves per group. BisCover LV(TM) glaze was applied to one of the two buccal half surfaces of randomly selected 13 teeth per group. For the other remaining 13 teeth per group, we applied Fortify(TM) glaze to one of the two half surfaces. The remaining 26 buccal half surfaces per group covered with sealant only, did not receive any glaze. The surface roughness and hardness of each sample was measured, and the average value of the three measurements from the individual sample was calculated. The sample surfaces were also observed by scanning an electron microscopy. RESULTS: Two-way ANOVA with surface roughness and hardness as the individual dependent variables identified a statistically significant interaction between the sealants and glazing materials. BisCover LV lowered Ultraseal XT surface roughness and application of surface glazing materials on 3M Concise promoted the hardness. Micro-cracks were identified on the surface in no glaze compared to being less in any glaze. CONCLUSIONS: Surface glaze material could improve the surface roughness and hardness of the selected pit and fissure sealant material. Such a sealant-reinforcing procedure, involving surface glazing, may be clinically useful.
Acrylates ; Bicuspid ; Electrons ; Hardness ; Pit and Fissure Sealants ; Resin Cements ; Tooth

Xanthocillin is a unique natural product with an isonitrile group and shows remarkable antibacterial activity. In this study, the genome of an endophytic fungus Penicillium chrysogenum MT-40 isolated from Huperzia serrata was sequenced, and the gene clusters with the potential to synthesize xanthocillin analogues were mined by local BLAST and various bioinformatics analysis tools. As a result, a biosynthetic gene cluster (named for) responsible for the biosynthesis of xanthocillin analogues was identified by further heterologous expression of the key genes in Aspergillus oryzae NSAR1. Specifically, the ForB catalyzes the synthesis of 2-formamido-3-(4-hydroxyphenyl) acrylic acid, and the ForG catalyzes the dimerization of 2-formamido-3-(4-hydroxyphenyl) acrylic acid to produce the xanthocillin analogue N, N'-(1, 4-bis (4-hydroxyphenyl) buta-1, 3-diene-2, 3-diyl) diformamide. The results reported here provide a reference for further discovery of xanthocillin analogues from fungi.
Penicillium chrysogenum/genetics* ; Huperzia/microbiology* ; Acrylates ; Multigene Family

STATEMENT OF PROBLEM: Microleakage at the occlusal and gingival margin of Class V cavities restored with composite resin has traditionally been considered an obstacle to successful restoration. PURPOSE: The aim of this study was to assess the effectiveness of three different surface sealants(Fortify, Permaseal and Biscover LV) on the marginal sealing of Class V light-activated composite resin restorations(Z250). MATERIAL AND METHODS: Forty noncarious human premolars and molars extracted within a three-month period were selected. Class V cavities with the occlusal margin in enamel and gingival margin in cementum were prepared in both buccal and lingual surfaces. The teeth, randomly assigned in four groups with twenty cavities in each group, were restored with composite resin after applying an adhesive system(Clearfil SE bond). After the finishing and polishing procedures, the restorations were covered with a specific surface sealants, except for the control samples, which were not sealed. After placing restorations, the specimens were thermocycled, and immersed in a 2% methylene blue solution for twenty four hours and sectioned longitudinally. The marginal microleakage was evaluated at the occlusal and gingival interfaces using a microscope and compared among the four groups using ANOVA test and Wilcoxon Rank-Sum test(alpha=0.05). RESULTS: Statistical analysis showed that there was significantly less leakage when the surface sealants were used than there was in control group (P < .05). There were no significant differences of microleakage at occlusal and gingival margins among groups. There were no significant differences between microleakage of occlusal and gingival margins in each group. Fortify was not statistically different from control group at the gingival margin (P > .05). CONCLUSION: Application of surface sealants was an effective method of surface coating in reducing microleakage at occlusal and gingival margins of Class V composite resin restorations. However, it is certain that some microleakage still occurred despite the application of surface sealants, especially gingival margins.
Acrylates ; Adhesives ; Bicuspid ; Dental Cementum ; Dental Enamel ; Humans ; Methylene Blue ; Molar ; Resin Cements ; Tooth

OBJECTIVE: To prepare ion exchange doxorubicin-loaded poly (acrylic acid) microspheres (DPMs) and evaluate the properties of these chemoembolic agents. METHODS: Poly (acrylic acid) microspheres (PMs) without drug were prepared by inverse suspension polymerization method and then doxorubicin was loaded by ion exchange mechanism to prepare DPMs. Optical microscope was used to investigate the morphology and particle size distribution of PMs and DPMs; fluorescence microscope and confocal microscope were used to observe the distribution of doxorubicin after drug loading. Elasticities of both the microspheres were evaluated by texture analyzer. High performance liquid chromatography (HPLC) method was established to determine the drug loading behavior of PMs and releasing behavior of DPMs. The in vivo embolic property was evaluated by embolizing the hepatic artery of a rabbit with 0.1 mL of DPMs. RESULTS: PMs and DPMs were both spherical in shape, smooth in surface and dispersed well. Doxorubicin was mainly in the outer area inside of DPMs and distributed evenly. The average particle size of PMs and DPMs were (283±136) μm and (248±149) μm, respectively. PMs and DPMs both had good compression ability with the Young's modulus of (62.63±1.65) kPa and (93.94±1.10) kPa separately. PMs reached the drug loading balance at 12 h, and the entrapment efficiency was greater than 99%. Drug loading of PMs in doxorubicin solution at the concentration of 5.0 g/L and 12.5 g/L was (19.78±0.27) g/L and (49.45±0.37) g/L, respectively. Doxorubicin released slowly from DPMs in PBS and the accumulative release percentages of DPMs with corresponding drug loading were 6.82%±0.02% and 2.83%±0.10% after 24 h, respectively. Arterial angiograms showed that the hepatic artery of the rabbit was successfully embolized with DPMs. CONCLUSION DPMs with good performance of loading doxorubicin could be a potential embolic agent for transcatheter arterial chemoembolization.
Acrylates ; Animals ; Doxorubicin/administration & dosage* ; Embolization, Therapeutic/methods* ; Microspheres ; Particle Size ; Rabbits

OBJECTIVETo investigate the preparation method of polystyrene core-poly (acrylamide-acrylic acid) shell fluorescent microspheres.

METHODSThe polystyrene core-poly (acrylamide-acrylic acid) shell (P-(St-co-AAM)) fluorescent microspheres were prepared using fluorescent microspheres as the core and acrylamide/acrylic as polymerization monomer. Reaction conditions affecting the morphology of core-shell structure including feeding mode, initiator, cross linker, pH, concentration and swelling were studied.

RESULTFluorescent microscopy showed that the relatively uniform particle sizes were distributed in a range of 7-8 μm. Fourier transform infra-red spectroscopy (FT-IR) proved the existence of poly (acrylamide-acrylic acid) shell and amide group on the surface. The optimal conditions for seeding polymerization: azobisisobutyronitrile was used as the initiator in the absence of cross linker, after a 40 h swelling treatment by using alcohol with the appropriate reaction temperature (70 degree), reaction time (3 h) and pH(6-7). The average dispersion and stability were 25.14 % and 90.21%, respectively. The fluorescein release percentage was kept stable at approximately 30% after 40 h.

CONCLUSIONThe fluorescent microspheres prepared by this method have core-shell structure and satisfactory fluorescence properties with good dispersion and stability.

Acrylates ; chemistry ; Acrylic Resins ; chemistry ; Fluorescein ; chemistry ; Microspheres ; Polymerization ; Polystyrenes ; chemistry

OBJECTIVE: The aim of this study was to investigate the experimental brush wear pattern of a light cured surface sealant, Biscover (Bisco, Schaumburg, IL), and to evaluate its cariostatic effect. METHODS: Caries- free human premolars were used for the Biscover coating group (n = 90) and the control group (n = 10). The Biscover coating group was randomly assigned to nine subgroups of 10 each and the control group was assigned to two subgroups of 5 each according to the number of brushing strokes. An experimental 3-body wear test was conducted under different strokes of wear test. Tooth-brushing was accomplished with movement of each brush head set at a frequency of 100 rpm under a force of 1.5 N. Surface roughness was tested before, and after Biscover coating, and after brushing. Then, each of the 10 teeth of both groups were placed in artificial caries inducing solution for 7 days. All tooth surfaces were assessed using scanning electron microscopy. RESULTS: Biscover coated surfaces showed a smoother texture than enamel surfaces. The roughness was increased after experimental brushing and after 10,800 brushing strokes, the whole layer of Biscover wore out. However, teeth in the Biscover coating group had a cariostatic effect in cariogenic conditions. CONCLUSIONS: We suggest that white lesions in orthodontic patients can be suppressed by topical applications of Biscover.
Acrylates ; Bicuspid ; Cariostatic Agents ; Dental Enamel ; Head ; Humans ; Light ; Microscopy, Electron, Scanning ; Resin Cements ; Stroke ; Tooth

During a composite resin restoration, an anticipating contraction gap is usually tried to seal with low-viscosity resin after successive polishing, etching, rinsing and drying steps, which as a whole is called rebonding procedure. However, the gap might already have been filled with water or debris before applying the sealing resin. We hypothesized that microleakage would decrease if the rebonding agent was applied before the polishing step, i.e., immediately after curing composite resin. On the buccal and lingual surfaces of 35 extracted human molar teeth, class V cavities were prepared withthe occlusal margin in enamel and the gingival margin in dentin. They were restored with a hybrid composite resin Z250 (3M ESPE, USA) using an adhesive AdperTM Single Bond 2 (3M ESPE). As rebonding agents, BisCover LV (Bisco, USA), ScotchBond Multi-Purpose adhesive (3M ESPE) and an experimental adhesive were applied on the restoration margins before polishing step or after successive polishing and etching steps. The infiltration depth of 2% methylene blue into the margin was measured using an optical stereomicroscope. The correlation between viscosity of rebonding agents and mciroleakage was also evaluated. There were no statistically significant differences in the microleakage within the rebonding procedures, within the rebonding agents, and within the margins. However, when the restorations were not rebonded, the microleakage at gingival margin was significantly higher than those groups rebonded with 3 agents (p < 0.05). The difference was not observed at the occlusal margin. No significant correlation was found between viscosity of rebonding agents and microleakage, except very weak correlation in case of rebonding after polishing and etching at gingival margin (r = -0.326, p = 0.041).
Acrylates ; Adhesives ; Bisphenol A-Glycidyl Methacrylate ; Chimera ; Contracts ; Dental Enamel ; Dentin ; Humans ; Methylene Blue ; Molar ; Resin Cements ; Tooth ; Viscosity

BACKGROUND: Insulin-mediated glucose uptake in insulin target tissues is correlated with interstitial insulin concentration, rather than plasma insulin concentration. Therefore, insulin delivery to the interstitium of target tissues is very important, and the endothelium may also play an important role in the development of insulin resistance. METHODS: After treating bovine aortic endothelial cells with angiotensin II (ATII), we observed the changes in insulin binding capacity and the amounts of insulin receptor (IR) on the cell membranes and in the cytosol. RESULTS: After treatment of 10(-7)M ATII, insulin binding was decreased progressively, up to 60% at 60 minutes (P<0.05). ATII receptor blocker (eprosartan) dose dependently improved the insulin binding capacity which was reduced by ATII (P<0.05). At 200 microM, eprosartan fully restored insulin binding capacity, althogh it resulted in only a 20% to 30% restoration at the therapeutic concentration. ATII did not affect the total amount of IR, but it did reduce the amount of IR on the plasma membrane and increased that in the cytosol. CONCLUSION: ATII decreased the insulin binding capacity of the tested cells. ATII did not affect the total amount of IR but did decrease the amount of IR on the plasma membrane. Our data indicate that ATII decreases insulin binding by translocating IR from the plasma membrane to the cytosol. The binding of insulin to IR is important for insulin-induced vasodilation and transendothelial insulin transport. Therefore, ATII may cause insulin resistance through this endothelium-based mechanism.
Acrylates ; Angiotensin II ; Angiotensins ; Cell Membrane ; Cytosol ; Endothelial Cells ; Endothelium ; Glucose ; Imidazoles ; Insulin ; Insulin Resistance ; Plasma ; Receptor, Insulin ; Thiophenes ; Vasodilation

OBJECTIVETo study the chemical constituents of Hedysarum polybotrys.

METHODChromatographic methods were used to isolate compounds from H. polybotrys and chemical and spectral methods were used to elucidate the structures of the isolated compounds.

RESULTFive compounds, N,N,N-trimethyl-tropaphone inner salt (hypaphorine) (1), octadecyl-3-methoxy-4-hydroxy-benzeneacrylate (2), 5,7,4'-trihydroxy-dihydroflavanone 5,7-di-O-beta-D-glucopyranoside (3), 3,4,5-trimethoxy cinnamic acid methy ester (4) and vanillic acid (5), were isolated from the roots of H. polybotrys.

CONCLUSIONCompounds 1, 2 and 3 were obtained from this plant for the first time, while compounds 1 and 2 were isolated from Hedysarum for the first time.

Acrylates ; chemistry ; isolation & purification ; Fabaceae ; chemistry ; Indoles ; chemistry ; isolation & purification ; Molecular Conformation ; Molecular Structure ; Plant Roots ; chemistry ; Plants, Medicinal ; chemistry

PURPOSE: The aim of this study is to examine the effect Klorhex and Fittydent, which are used as cleaning agents on the adhesion of Candida on the surfaces of acrylic denture and palatal mucosa. In addition, ability of yeasts to adhere to acrylic strips was evaluated after applying these agents in vitro. MATERIALS and METHODS: Each group of 15 patients cleaned their dentures with either Klorhex or with Fittydent. The control group cleaned their dentures with water. RESULTS: It was found that 62.2% of the patients had colonies of Candida species on their palatal mucosa which was reduced to 51.1% after using these cleaning agents. The colonization rate with Candida spp on their dentures was reduces from 82.2% to 68.8% using these cleaning agents. The mean adhesion value of the Candida strains isolated from the acrylic strips were found to be 75cell/strip prior to applying the Klorhex and Fittydent and 37.5cell/strip and 15cell/strip after applying these agents, respectively. CONCLUSION: These results showed that Klorhex and Fittydent have a certain preventive effect on the colonization rate of Candida spp on the surface of these dentures, the palatal mucosa, as well as on the acrylic strips in vitro.
*Acrylates ; Adhesiveness/drug effects ; Antifungal Agents/*pharmacology ; Candida/*cytology/*drug effects ; Cell Adhesion/drug effects ; Denture Cleansers/*pharmacology ; *Dentures ; Mouth Mucosa/drug effects/microbiology ; Polyvinyls/pharmacology