PURPOSE: The aim of this study was to determine the efficiency of Erbium, Chromium: Yttrium-Scandium-Gallium-Garnet laser in different output powers for removing permanent resin cement residues and therefore its influence on microshear bond strength compared to other cleaning methods. MATERIALS AND METHODS: 90 extracted human molars were sectioned in 1 mm thickness. Resin cement was applied to surface of sliced teeth. After the removal of initial cement, 6 test groups were prepared by various dentin surface treatment methods as follows: no treatment (Group 1), ethylene diamine tetra acetic acid application (Group 2), Endosolv R application (Group 3), 1.25 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 4), 2 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 5) and 3.5 W Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet laser irradiation (Group 6). The topography and morphology of the treated dentin surfaces were investigated by scanning electron microscopy (n=2 for each group). Following the repetitive cementation, microshear bond strength between dentin and cement (n=26 in per group) were measured with universal testing machine and the data were analyzed by Kruskal Wallis H Test with Bonferroni correction (P<.05). Fracture patterns were investigated by light microscope. RESULTS: Mean microshear bond strength +/- SD (MPa) for each group was 34.9 +/- 17.7, 32.1 +/- 15.8, 37.8 +/- 19.3, 31.3 +/- 12.7, 44.4 +/- 13.6, 40.2 +/- 13.2 respectively. Group 5 showed significantly difference from Group 1, Group 2 and Group 4. Also, Group 6 was found statistically different from Group 4. CONCLUSION: 2 W and 3.5 W Erbium, Chromium: Yttrium-Scandium-Gallium-Garnet laser application were found efficient in removing resin residues.
Acetic Acid ; Cementation ; Characidae ; Chromium ; Dentin* ; Erbium ; Humans ; Microscopy, Electron, Scanning ; Molar ; Resin Cements ; Tooth

PURPOSE: Image-based computational models with fluid-structure interaction (FSI) can be used to perform plaque mechanical analysis in intracranial artery stenosis. We described a process in FSI study applied to symptomatic severe intracranial (M1) stenosis before and after stenting. MATERIALS AND METHODS: Reconstructed 3D angiography in STL format was transferred to Magics for smoothing of vessel surface and trimming of branch vessels and to HyperMesh for generating tetra volume mesh from triangular surface-meshed 3D angiogram. Computational analysis of blood flow in the blood vessels was performed using the commercial finite element software ADINA Ver 8.5. The distribution of wall shear stress (WSS), peak velocity and pressure was analyzed before and after intracranial stenting. RESULTS: The wall shear stress distributions from Computational fluid dynamics (CFD) simulation with rigid wall assumption as well as FSI simulation before and after stenting could be compared. The difference of WSS between rigid wall and compliant wall model both in pre- and post-stent case is only minor except at the stenosis region. These WSS values were greatly reduced after stenting to 15~20 Pa at systole and 3~5 Pa at end-diastole in CFD simulation, which are similar in FSI simulations. CONCLUSION: Our study revealed that FSI simulation before and after intracranial stenting was feasible despite of limited vessel wall dimension and could reveal change of WSS as well as flow velocity and wall pressure.
Angiography ; Arteries ; Atherosclerosis ; Blood Vessels ; Cerebral Arteries ; Characidae ; Constriction, Pathologic ; Glycosaminoglycans ; Hydrodynamics ; Magic ; Stents ; Systole

Tetra cell adhesion molecule(T-CAM) is a new recombinant mixture of fibronectin and ig-h3. Fibronectin and ig-h3 are extracellular matriprotein involved in each phase of wound healing, and the combination of these materials may generate a synergistic effect in wound healing. Regenin is easily attainable from protein recombination. It can be developed as wound healing material, and also it has a good effect in cell adhesion and proliferation. We combined the chitosan with regenin or T-CAM at different concentration, which are gene recombination material. They were applied to the artificial wound of white rabbit to compare the healing effect in each group. Round full thickness skin defects, 3 cm in diameter, were made bilaterally on the dorsolateral aspect of New Zealand white rabbit. Experimental group was divided into 6 groups, according to concentration of T-CAM and regenin with chitosan-based dressing materials as followings; Group C: control group - oint material dressing, Group Ch: chitosan base only, Group T1: chitosan base in combination with 25 microgram/ml of T-CAM, Group T2: chitosan base in combination with 625 microgram/ml of T-CAM, Group R1: chitosan base in combination with 25 microgram/ml of Regenin, Group R2: chitosan base in combination with 625 microgram/ml of Regenin. Gross findings by means of percentage of wound contraction, percentage of wound epithelization and percentage of total wound healed area were compared with surface tracing of the remained wound area at the time of 7, 14, 21 days after wound formation. Wound biopsy were performed at the time of 7, 14, 21 days after wound formation. T1, T2 group and R1, R2 groups have less infiltration of inflammtory cell, fast appearance of new vessels, fibroblast, increased volume of collagen fiber comparing to C and Ch group. there's more statistical significance between T1 and T2 group. The same results were shown in Regenin group. In conclusion, our results suggest that T-CAM and Regenin have good effect in wound healing and higher concentration of T-CAM and Regenin is more effective in wound healing than lower concentration. In addition, comparision of same concentration of T-CAM and Regenin group presented almost same results.
Bandages ; Biopsy ; Cell Adhesion ; Characidae ; Chitosan* ; Collagen ; Fibroblasts ; Fibronectins ; New Zealand ; Porifera* ; Recombination, Genetic ; Skin ; Wound Healing* ; Wounds and Injuries*

Hypoxic pulmonary vasoconstriction(HPV) plays an important role in matching ventilation and perfusion, and in a homeostatic compensatory mechanism for maintaining arterial blood oxygen tension. The purpose of this study was to explore effect of hypoxia on the vascular tension and to elucidate mechanism underlying hypoxic pulmonary vasoconstriction. The ring segments of the pulmonary artery were taken from forty rabbits(2~2.5 kg, male). Each ring was attached to an isometric force transducer(Grass FT-03) and suspended in a tissue bath(37degrees C) filled with 5 ml Krebs solution, aerated with 95% O2 + 5% CO2(pH 7.4) gas mixture. During 90 minutes of equilibrium period, the Krebs solution was changed every 15 minutes and the last resting tension was adjusted to 2 gm. After precontraction of the preparations with K(+) 40 mM, the aerating gas mixture was replaced by hypoxic gas(95% N2 + 5% CO2) and changes in vascular tension of isolated pulmonary artery with(n=36) and without endothelium(n=14) were recorded for 60 minutes. HPV induced biphasic vasoactive effects. To determine the mechanism of the vasorelaxing response, the pulmonary arterial rings were pretreated with indomethacin(n=8), L-nitro(w) arginine methyl ester(L-NAME, n=l0), tetra ethyl ammonium(TEA, n=12), glybenclamide(n=l1). And also to elucidate the mechanism of the hypoxic vasoconstricting response, effects of Ca free solution and pretreatment of ryanodine on the HPV were examined. The results obtained were as follows: 1) Transient phase 1 contraction followed by long lasting(about 30 minutes) relaxation and sustained phase 2 contraction were induced by hypoxic gas(95% N2+5% CO2) in rabbit pulmonary artery. 2) In endothelium removed pulmonary artery, transient phase 1 contraction was not apparent. 3) Vasorelaxation was partially blocked by K' channel blockers(TEA, glybenclamide). 4) Indomethacin and L-NAME pretreatments did not affect on the vasorelaxing response of the HPV to hypoxia. 5) Sustained phase 2 contraction was blocked by calcium free Krebs solution. 6) Indomethacin and ryanodine pretreatments did not change the phase 1 and phase 2 vasocontsricting reponses. The results of present study suggest that hypoxia-induced phase 1 contractile response is endothelium dependent, while phase 2 contractile response is dependent on calcium influx, and that the vasorelaxant response is partially mediated by K(+) channel.
Anoxia ; Arginine ; Calcium ; Characidae ; Endothelins ; Endothelium ; Indomethacin ; NG-Nitroarginine Methyl Ester ; Oxygen ; Perfusion ; Pulmonary Artery* ; Relaxation ; Ryanodine ; Vasoconstriction* ; Vasodilation ; Ventilation

PURPOSE: Computational flow dynamic (CFD) study has not been widely applied in intracranial artery stenosis due to requirement of high resolution in identifying the small intracranial artery. We described a process in CFD study applied to symptomatic severe intracranial (M1) stenosis before and after stenting. MATERIALS AND METHODS: Reconstructed 3D angiography in STL format was transferred to Magics (Materialise NV, Leuven, Belgium) for smoothing of vessel surface and trimming of branch vessels and to HyperMesh (Altair Engineering Inc., Auckland, New Zealand) for generating tetra volume mesh from triangular surface-meshed 3D angiogram. Computational analysis of blood flow in the blood vessels was performed using the commercial finite element software ADINA Ver 8.5 (ADINA R & D, Inc., Lebanon, MA). The distribution of wall shear stress (WSS), peak velocity and pressure in a patient was analyzed before and after intracranial stenting. RESULTS: Computer simulation of wall shear stress, flow velocity and wall pressure before and after stenting could be demonstrated three dimensionally by video mode according to flow vs. time dimension. Such flow model was well correlated with angiographic finding related to maximum degree of stenosis. Change of WSS, peak velocity and pressure at the severe stenosis was demonstrated before and after stenting. There was no WSS after stenting in case without residual stenosis. CONCLUSION: Our study revealed that CFD analysis before and after intracranial stenting was feasible despite of limited vessel wall dimension and could reveal change of WSS as well as flow velocity and wall pressure.
Angiography ; Arteries ; Atherosclerosis ; Blood Vessels ; Cerebral Arteries ; Characidae ; Computer Simulation ; Constriction, Pathologic ; Glycosaminoglycans ; Humans ; Lebanon ; Magic ; Stents

BACKGROUND: EDTA was added to the formulation of propofol to inhibit microbial growth due to accidental extrinsic contamination. This study was conducted to determine whether the EDTA in the propofol would affect the ionized calcium homeostasis, other electrolyte balance, blood urea nitrogen (BUN) and creatinine (Cr) in long time craniotomy patients. METHODS: Forty two patients undergoing surgery for clipping of a cerebral aneurysm were randomly assigned to receive either propofol without EDTA (propofol group; n = 20), or propofol with EDTA (propofol EDTA group; n = 22). The ionized calcium, total calcium, total magnesium, phosphate, potassium, sodium, BUN and Cr in the blood were measured at before anesthetic induction, 4 hours after induction and 1 hour after the operation. RESULTS: There were no significant differences in the ionized calcium, other electrolytes, BUN and Cr between the two groups. CONCLUSIONS: The addition of EDTA into propofol appears to have no significant effects on the electrolyte balance, BUN and Cr concentration.
Blood Urea Nitrogen ; Calcium ; Characidae* ; Craniotomy ; Creatinine* ; Edetic Acid* ; Electrolytes ; Homeostasis ; Humans ; Intracranial Aneurysm ; Magnesium ; Potassium ; Propofol* ; Sodium ; Water-Electrolyte Balance

PURPOSE: The purpose of this study was to compare the effect of a diode laser and traditional irrigants on the bond strength of self-adhesive cement. MATERIALS AND METHODS: Fifty-five incisors extracted due to periodontal problems were used. All teeth were instrumented using a set of rotary root canal instruments. The post spaces were enlarged for a No.14 (diameter, 1.4 mm) Snowlight (Abrasive technology, OH, USA) glass fiber reinforced composite post with matching drill. The teeth were randomly divided into 5 experimental groups of 11 teeth each. The post spaces were treated with the followings: Group 1: 5 mL 0.9% physiological saline; Group 2: 5 mL 5.25% sodium hypochlorite; Group 3: 5 mL 17% ethylene diamine tetra acetic acid (EDTA), Group 4: 37% orthophosphoric acid and Group 5: Photodynamic diode laser irradiation for 1 minute after application of light-active dye solution. Snowlight posts were luted with self-adhesive resin cement. Each root was sectioned perpendicular to its long axis to create 1 mm thick specimens. The push-out bond strength test method was used to measure bond strength. One tooth from each group was processed for scanning electron microscopic analysis. RESULTS: Bond strength values were as follow: Group 1 = 4.15 MPa; Group 2 = 3.00 MPa; Group 3 = 4.45 MPa; Group 4 = 6.96 MPa; and Group 5 = 8.93 MPa. These values were analysed using one-way ANOVA and Tukey honestly significant difference test (P<.05). Significantly higher bond strength values were obtained with the diode laser and orthophosphoric acid (P<.05). There were no differences found between the other groups (P>.05). CONCLUSION: Orthophosphoric acid and EDTA were more effective methods for removing the smear layer than the diode laser. However, the diode laser and orthophosphoric acid were more effective at the cement dentin interface than the EDTA, Therefore, modifying the smear layer may be more effective when a self-adhesive system is used.
Acetic Acid ; Axis, Cervical Vertebra ; Characidae ; Dental Pulp Cavity ; Dentin ; Edetic Acid ; Ethylenes ; Glass ; Incisor ; Lasers, Semiconductor* ; Methods ; Phosphoric Acids ; Resin Cements ; Smear Layer ; Sodium Hypochlorite ; Tooth

BACKGROUND/AIMS: The heavy metals like cadmium (Cd) are neither destroyed nor produced in human body and may infiltrated into air, water, soil, food, human body and redistributed by biological and geographical circulation. With advent of recent industrialization detrimental heavy metal poisoning in human body is increased by industrial pollution. We aimed to establish the relative abilities of chelators to mobilized liver cadmium contents in chronic cadmium intoxication rats. METHODS: Sprague-Dawley albino male rats weighing 200 to 250 mg were used. All animals were loaded with 3 intraperitoneal injections of cadmium chloride (1.5 mg/kg) given at % hourly interval. Intraperitoneal injection of chelators commenced 1 week after the last loading injection and continued every 72 hour for a total of 10 injections. Chelators were given at a level of 1 mmole/kg (except 0.01 mmol/kg of BAL). The chelators used in present experiment are 1,2-diaminocyclohexane tetra acetate (CDTA), disodium calcium ethylene diamine tetra acetate (EDTA), sodium 2.3-dimer capto propane sulfonate (DMPS), sodium di ethyl dithio carbamate (DDTC), dimercapto succinate (DMSA), 2,3-dimer capto propanol (BAL), diethylene triamine penta acetate (DTPA), triethylene tetr amine hexa acetate (TTHA), D-penicillamine(DPA), Nacetyl penicillamine (NAPA). RESULTS: 1) The residual liver cadmium content was reduced in rats administered DPA, EDTA, NAPA, CDTA, DDTC and DMSA (32%, 23%, 19%, 17%, 16% and 15% respectively) compared with control group. 2) The residual kidney cadmium content was reduced in rats administered DPA, DDTC, CDTA and EDTA (33%, 21%, 18% and 17% respectively) 3) The summation of residual cadmium content in liver and kidney was reduced in rats administered DPA, EDTA, DDTC and CDTA (33%, 20%, 18% and 17% respectively) compared with control group. CONCULUSIONS: We suggested that DPA, EDTA, CDTA and DDTC might have protective role against the toxic effects of cadmium.
1-Propanol ; Animals ; Cadmium Chloride ; Cadmium* ; Calcium ; Characidae ; Chelating Agents* ; Edetic Acid ; Human Body ; Humans ; Injections, Intraperitoneal ; Kidney ; Liver* ; Male ; Metals, Heavy ; Penicillamine ; Poisoning ; Propane ; Rats* ; Rats, Sprague-Dawley ; Sodium ; Soil ; Succimer ; Succinic Acid

BACKGROUND AND OBJECTIVES: Variety of pathological factors including viral hepatitis, alcohol and drug abuse, metabolic diseases, autoimmune diseases and congenital abnormalities can cause hepatic injury. Liver transplantation is the treatment of choice for end-stage liver diseases, however, it faces several difficulties. So the aim of the work is to evaluate the effect of bone marrow derived mesenchymal stem cells (BM-MSCs) on the liver structure in carbon tetra chloride CCL4 induced liver fibrosis in rats. MATERIALS AND RESULTS: BM-MSCs were isolated and characterized from long bones of twenty male albino rats. Sixty female rats were divided into the following two groups: Group I; thirty rats which were the control group. Group II; thirty rats were injected intra-peritoneal (IP) by CCL4 twice weekly for four weeks and was further subdivided into the following three subgroups: Subgroup IIA (CCL4 alone); included ten rats which were sacrificed after this four weeks. Subgroup IIB (CCL4/MSCs); included ten rats which were IP injected by a single dose of BM-MSCs and were sacrificed after four weeks. Subgroup IIC (CCL4/recovery); included ten rats which were left for another four weeks without any intervention. Histological examination of liver specimens showed that CCl4 caused variable pathological changes with elevated liver enzymes. Injection of BM-MSCs revealed an improvement in the histological picture of the liver and its enzymatic profile. On the other hand, most of the pathological lesion were still detected in rats of recovery group. CONCLUSIONS: BM-MSC could restore the liver structure and function in experimental model of liver fibrosis.
Animals ; Autoimmune Diseases ; Bone Marrow* ; Carbon ; Characidae ; Congenital Abnormalities ; Female ; Fibrosis ; Hand ; Hepatitis ; Humans ; Liver ; Liver Cirrhosis* ; Liver Diseases ; Liver Transplantation ; Male ; Mesenchymal Stromal Cells* ; Metabolic Diseases ; Models, Theoretical ; Rats* ; Substance-Related Disorders