Advances in cancer photodynamic therapy / 中国药科大学学报

@#Abstract:Photodynamic therapy(PDT)is a minimal invasive therapy that have been clinically approved for the cancer treatment with selective cell toxicity. When activated by appropriate wavelength of light, photosensitizers transfer the absorbed photon energy to the surrounding molecular oxygen to generate reactive oxygen species, which result in cell death, vessel damage and immune activation of tumor site. This paper summarize the main challenges and recent solutions for PDT application, such as the low tissue penetration of light, toxicity induced by nonspecific accumulation of skin and poor PDT effect of hypoxia tumor.

Effect of Morinda Citrifolia Juice and Triphala as Root Canal Irrigants on Sealer Penetration Depth Into the Dentinal Tubules. – A Confocal Laser Microscope Study.

Aim: The aim of this study was to evaluate the effect of Morinda citrifolia juice (MCJ) and Triphala on sealer penetration depth into the dentinal tubules as root canal irrigants. Materials and Methods: Forty five single rooted extracted human teeth were collected; decoronated and root canal length were standardized to16mm. Cleaning and shaping was done with protaper universal rotary instruments till F5. 30 samples were selected randomly and divided into two groups with 15 samples in each, according to the final irrigation regimen. In Group I, 5 ml of MCJ was used for 1min and in Group II; 5 ml of Triphala was used. The remaining 15 samples were irrigated with 5ml of Smear clear which acted as a positive control Group. Obturation was done with corresponding gutta-percha points and AH 26 sealer (Dentsply; DeTrey, Konstanz, Germany) labelled with fluorescent dye and left to set for 48 hrs. Then, the roots were sectioned and subjected to confocal laser microscope. Results: Statistical analysis was done by two-way analysis of variance (ANOVA) and Tukey multiple post-hoc procedures. The sealer penetration depth is higher in the MCJ group than the Triphala group at all three levels. Conclusion: MCJ showed a significant sealer penetration depth than Triphala.

Evaluation of penetration depth of 2% chlorhexidine digluconate into root dentinal tubules using confocal laser scanning microscope

OBJECTIVES: This study evaluated the penetration depth of 2% chlorhexidine digluconate (CHX) into root dentinal tubules and the influence of passive ultrasonic irrigation (PUI) using a confocal laser scanning microscope (CLSM). MATERIALS AND METHODS: Twenty freshly extracted anterior teeth were decoronated and instrumented using Mtwo rotary files up to size 40, 4% taper. The samples were randomly divided into two groups (n = 10), that is, conventional syringe irrigation (CSI) and PUI. CHX was mixed with Rhodamine B dye and was used as the final irrigant. The teeth were sectioned at coronal, middle and apical levels and viewed under CLSM to record the penetration depth of CHX. The data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests. RESULTS: The mean penetration depths of 2% CHX in coronal, middle and apical thirds were 138 microm, 80 microm and 44 microm in CSI group, respectively, whereas the mean penetration depths were 209 microm, 138 microm and 72 microm respectively in PUI group. Statistically significant difference was present between CSI group and PUI group at all three levels (p < 0.01 for coronal third and p < 0.001 for middle and apical thirds. On intragroup analysis, both groups showed statistically significant difference among three levels (p < 0.001). CONCLUSIONS: Penetration depth of 2% CHX into root dentinal tubules is deeper in coronal third when compared to middle and apical third. PUI aided in deeper penetration of 2% CHX into dentinal tubules when compared to conventional syringe irrigation at all three levels.

Evaluation of penetration depth of 2% chlorhexidine digluconate into root dentinal tubules using confocal laser scanning microscope

OBJECTIVES: This study evaluated the penetration depth of 2% chlorhexidine digluconate (CHX) into root dentinal tubules and the influence of passive ultrasonic irrigation (PUI) using a confocal laser scanning microscope (CLSM). MATERIALS AND METHODS: Twenty freshly extracted anterior teeth were decoronated and instrumented using Mtwo rotary files up to size 40, 4% taper. The samples were randomly divided into two groups (n = 10), that is, conventional syringe irrigation (CSI) and PUI. CHX was mixed with Rhodamine B dye and was used as the final irrigant. The teeth were sectioned at coronal, middle and apical levels and viewed under CLSM to record the penetration depth of CHX. The data were statistically analyzed using Kruskal-Wallis and Mann-Whitney U tests. RESULTS: The mean penetration depths of 2% CHX in coronal, middle and apical thirds were 138 microm, 80 microm and 44 microm in CSI group, respectively, whereas the mean penetration depths were 209 microm, 138 microm and 72 microm respectively in PUI group. Statistically significant difference was present between CSI group and PUI group at all three levels (p < 0.01 for coronal third and p < 0.001 for middle and apical thirds. On intragroup analysis, both groups showed statistically significant difference among three levels (p < 0.001). CONCLUSIONS: Penetration depth of 2% CHX into root dentinal tubules is deeper in coronal third when compared to middle and apical third. PUI aided in deeper penetration of 2% CHX into dentinal tubules when compared to conventional syringe irrigation at all three levels.

Influence of plugger penetration depth on the apical extrusion of root canal sealer in continuous wave of condensation technique / 대한치과보존학회지

The purpose of this study was to evaluate the influence of plugger penetration depth on the apical extrusion of root canal sealer during root canal obturation with Continuous Wave of Condensation Technique. Root canals of forty extracted human teeth were divided into four groups and were prepared up to size 40 of 0.06 taper with ProFile. After drying, canals of three groups were filled with Continuous Wave of Condensation Technique with System B(TM) and different plugger penetration depths of 3, 5, and 7 mm from the apex. Canals of one group were filled with cold lateral compaction technique as a control. Canals were filled with non-standardized master gutta-percha cones and 0.02 mL of Sealapex. Apical extruded sealer was collected in a container and weighed. Data was analyzed with one-way ANOVA and Duncan's Multiple Range Test. 3 and 5 mm penetration depth groups in Continuous Wave of Condensation Technique showed significantly more extrusion of root canal sealer than 7 mm penetration depth group (p < 0.05). However, there was no significant difference between 7 mm depth group in Continuous Wave of Condensation Technique and cold lateral compaction group (p < 0.05). The result of this study demonstrates that deeper plugger penetration depth causes more extrusion of root canal sealer in root canal obturation by Continuous Wave of Condensation Technique. Therefore, special caution is needed when plugger penetration is deeper in the canal in Continuous Wave of Condensation Technique to minimize the amount of sealer extrusion beyond apex.

Depth profiling in membranes by fluorescence quenching.

Membrane penetration depth is an important parameter in relation to membrane structure and organization. A methodology has been developed to analyze the membrane penetration depths of fluorescent molecules or groups utilizing differential fluorescence quenching caused by membrane embedded spin-label probes located at different depths. The method involves determination of the parallax in the apparent location of fluorophores, detected when quenching by phospholipids spin-labelled at two different depths is compared. By use of relatively simple algebraic expressions, the method allows calculation of depth in Å. This method has been used to determine the location of fluorophores in NBD-labelled lipids and anthroyloxy-labelled fatty acids in model membranes and of the membrane embedded tryptophan residues in the reconstituted nicotinic acetylcholine receptor.