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Vascular involvement can be seen in up to 40% of patients with Behcet syndrome (BS), the lower-extremity vein thrombosis (LEVT) being the most common type. The aim of the current study was to compare venous Doppler findings and clinical features between BS patients with LEVT and control patients diagnosed as having LEVT due to other causes.All consecutive 78 patients (71 men, 7 women; mean age 38.6 ± 10.3 years) with LEVT due to BS and 50 control patients (29 men, 21 women; mean age 42.0 ± 12.5 years) who had LEVT due to other causes, or idiopathic, were studied with the help of a Doppler ultrasonography after a detailed clinical examination. Patterns of venous disease were identified by cluster analyses. Clinical features of chronic venous disease were assessed using 2 classification systems. Venous claudication was also assessed.Patients with BS were more likely to be men, had significantly earlier age of onset of thrombosis, and were treated mainly with immunosuppressives and less frequently with anticoagulants. Furthermore, they had significantly more bilateral involvement, less complete recanalization, and more frequent collateral formation. While control patients had a disorganized pattern of venous involvement, BS patients had a contiguous and symmetric pattern, involving all deep and superficial veins of the lower extremities, with less affinity for crural veins. Clinical assessment, as measured by the 2 classification systems, also indicated a more severe disease among the BS patients. In line, 51% of the BS patients suffered from severe post-thrombotic syndrome (PTS) and 32% from venous claudication, whereas these were present in 8% and 12%, respectively, among the controls. Among BS patients, a longer duration of thrombosis, bilateral femoral vein involvement, and using no anticoagulation along with immunosuppressive treatment when first diagnosed were found to be associated independently with severe PTS.Lower-extremity vein thrombosis associated with BS, when compared to LEVT due to other causes, had distinctive demographic and ultrasonographic characteristics, and had clinically a more severe disease course.  相似文献   
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PURPOSE: To evaluate the effect of saliva contamination on the microleakage of an etch-and-rinse adhesive and a self-etching adhesive. MATERIALS AND METHODS: Class V cavity preparations at the cementoenamel junction were made on the buccal and lingual surfaces of 40 freshly extracted human molars. The teeth were randomly assigned into two groups for different adhesives: Group I, Single Bond (two-step etch-and-rinse adhesive) and Group II, Futura Bond NR (one-step self-etching adhesive). The adhesive materials were applied according to their manufacturers' recommendations. The specimens were then further subdivided into five subgroups (A-E; n = 8): group A, contamination before adhesive curing; group B, contamination before adhesive curing and re-application of adhesive; group C, contamination after adhesive curing; group D, contamination after adhesive curing and re-application of adhesive; and group E, no contamination (control). Contamination of adhesive surfaces was performed with fresh natural saliva and the saliva was removed by a gentle air blast. The specimens were restored with Z250 hybrid composite. After thermocycling (500x, 5 degrees C to 55 degrees C) and immersion in 0.5% basic fuchsin, the dye penetration was evaluated under a stereomicroscope. Statistical analysis was performed with the Kruskal-Wallis test at p < 0.05. RESULTS: No statistically significant differences were found among the contamination subgroups on the enamel or on the dentin for either group (p > 0.05). There was no significant difference in leakage between Group I and Group II for any subgroup (p > 0.05). CONCLUSION: Contamination of adhesives with saliva before and after adhesive curing did not worsen the microleakage of the two-step etch-and-rinse adhesive Single Bond or the one-step self-etching adhesive Futura Bond NR.  相似文献   
4.
This study compared the temperature increase in a pulp chamber as a result of using various light-curing units during resin composite polymerization, and it determined the effect of remaining dentin thickness on temperature rise. A Class II occlusodistal cavity with a remaining dentin thickness of 2 mm was prepared in an extracted human mandibular molar. A 2-mm layer of fine hybrid resin composite was placed on the floor of the proximal box. A K-type thermocouple was inserted into pulp chambers filled with heat sink compound, and pulp chamber temperature rise (starting temperature: 37.0 +/- 0.1 degrees C) during polymerization of the composite was measured. The light-curing units tested included two halogen lights, Spectrum 800 and Elipar Trilight (Standard and Exponential mode); a light-emitting diode (LED, Elipar Freelight) and a plasma arc (Virtuoso, Xenon Power Arc). Irradiation time was 40 seconds for the halogen and LED lights and 3 seconds for the plasma arc light. Five measurements were carried out for every light-curing unit. The same experimental design was conducted after the cavity preparation was modified, leaving a 1-mm thick dentin layer. The Kruskal-Wallis and multiple comparison tests were used to evaluate the differences among the tested curing units. Mann Whitney-U tests were used to compare the mean temperature rise in each curing unit for different remaining dentin thicknesses. The increase in pulp chamber temperature ranged between 1.40-3.8 degrees C. The highest temperature rise was observed when using Elipar Trilight Standard mode, and the lowest temperature rise was observed with light emitting diode for both remaining dentin thicknesses. The only significant differences in temperature rise were observed between Elipar Trilight Standard mode and LED. No significant difference (p > 0.01) existed for the different modes of Elipar Trilight. A statistically significant higher temperature rise was observed within each curing unit at a depth of 1 mm compared to 2 mm. Although the tested light-curing units caused a temperature rise in the pulp chamber, none exceed the critical value of 5.5 degrees C.  相似文献   
5.

Introduction

Biocompatibility of pulp capping materials is important for successful use in dentistry. These materials should be nontoxic and permissive for proliferation and induction of odontogenic differentiation of pulp cells. The aim of our study was to evaluate the effects of enamel matrix derivative (EMD), mineral trioxide aggregate (MTA), and calcium hydroxide-containing cement (DYCAL) on proliferation and odontogenic differentiation of human tooth germ stem cells (hTGSCs) in which cells belonging to both pulp tissue and dental follicle exist.

Methods

The 96-well plates, 24-well plates, and special chamber slides were coated with biomaterials for cell proliferation, differentiation, and scanning electron microscopy analysis. Odontogenic differentiation of hTGSCs was evaluated by analyzing mRNA expression of dentin sialophosphoprotein (DSPP) by real-time polymerase chain reaction expression analysis, measurement of alkaline phosphatase activity, and visualization of calcium depositions by von Kossa staining.

Results

Our results demonstrate that EMD is the best material in terms of inducing differentiation and proliferation of hTGSCs. DYCAL was found to be toxic to hTGSCs; however, EMD-coated DYCAL showed less toxicity. EMD-coated MTA was not efficient at inducing proliferation and differentiation.

Conclusions

Pulp capping materials come in direct contact with dental pulp cells; thus, they require comprehensive evaluation of interactions between cells and biomaterials. Therefore, we cultured hTGSCs, capable of odontogenic differentiation, on pulp capping materials directly. Our results suggest that combination of capping materials with EMD would increase the quality of capping by increasing biocompatibility of capping materials.  相似文献   
6.
This study evaluated the bond strength of resin composite to dentin, mediated by a self-etching adhesive, following the application of various dentin desensitizing treatments and artificial saliva storage. The buccal cervical areas of 24 extracted human third molars were ground flat to expose cervical dentin. The dentin surfaces were polished with 1200-grit SiC paper, then the teeth were randomly assigned to six groups, five desensitizing treatments and one control: Group I-VivaSens; Group II-Fluor Protector; Group III-Isodan; Group IV-Futura Bond NR; Group V-Nd:YAG laser and Group VI-Control (without application of a desensitizing agent). After applying the desensitizing treatments and storing the molars in artificial saliva for 14 days at 37 degrees C, Futura Bond NR was used to bond resin composite to dentin. TPH composite build-ups were constructed incrementally to a height of 5 mm. The teeth were sectioned to obtain bonded slices of 0.7 mm thick specimens containing the resin-composite joint. The specimens were then trimmed into an hourglass shape and subsequently subjected to microtensile testing at a crosshead speed of 1 mm/minute. The data were analyzed using the Kruskal-Wallis analysis and multiple comparisons test. The control (Group VI) and Futura Bond NR self-etching treatment (Group IV) group yielded statistically significant higher bond strength values than the other desensitizing treatment groups tested (p < 0.005). While pretreatment of dentin surfaces with desensitizing agents (Fluor Protector, VivaSens and Isodan) and laser (Nd:YAG) reduced the bond strength values of the resin composite, higher bond strengths were achieved using a self-etching adhesive (Futura Bond NR) as a desensitizing agent.  相似文献   
7.

Purpose

QT dispersion (QTd) was shown to be an independent predictor of mortality in hemodialysis (HD) patients. It may be hypothesized that coronary artery calcification is related to QTd in HD patients because widespread calcification may also involve the cardiac conducting system in these patients. In this study, we aimed to investigate the relationships of corrected QTd (QTcd) with coronary artery calcification score (CACS), carotid plaque score (CPS) and possible influence of these parameters on survival of HD patients.

Methods

Seventy-two HD patients (33 male, 39 female) were enrolled into the study. Mean age of the patients was 44 ± 12 years. Mean follow-up duration was 77 ± 24 months. CACS was determined by computed tomography. QTcd values were calculated as the difference of maximum and minimum QT intervals. Left ventricular mass index (LVMI) and CPS were measured by echocardiography.

Results

QTcd was significantly correlated with CACS (r = 0.233, p = 0.049), CPS (r = 0.354, p = 0.003) and LVMI (p = 0.011, r = 0.299). CPS was found to be significantly higher in the group with high QTcd (>60 ms) [2 (1–4) versus 0 (0–1), p = 0.02]. CACS was significantly correlated with age (r = 0.44, p < 0.001), LVMI (r = 0.52, p < 0.001) and CPS (r = 0.32, p = 0.003). In Kaplan–Meier analysis, survival of patients with high QTcd was significantly lower than the patients with low QTcd. In Cox regression analysis for predicting mortality, age, serum albumin and QTcd were found to be the independent predictors of mortality.

Conclusions

QTcd independently predicted mortality, and it was significantly associated with coronary artery calcification, left ventricular hypertrophy and atherosclerosis in HD patients.  相似文献   
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