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71.
72.

Background:

Dentistry equipment are exposed to different types of pathogenic microorganisms. The aim of this study was to investigate the effect of spraying three different types of disinfectants on condensational silicones after 5 and 10 min.

Materials and Methods:

Totally, 66 circular samples of condensational silicone impression materials of 1 cm diameter and 2 mm thickness were contaminated by Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans fungus. Except for control samples, all of them were disinfected with sodium hypochlorite (NaOCl) 0.525%, Deconex and Epimax by spraying method. Afterward, they kept in plastic bags with humid rolled cotton for 5 and 10 min. In order to isolate microbiotas, the samples were immersed in 2% trypsin for 1 h and diluted with normal saline in a portion of 1, 1/2, and 1/4. The trypsin suspensions were transferred to culture plates for incubation and colony-forming unit assay. The data were analyzed by Mann–Whitney test and SPSS software version 16 at a significant level of 0.05.

Results:

There was a meaningful difference between disinfection effects of Epimax-Deconex for all mentioned microorganisms after 5 min (P = 0.034), and between disinfection effects of NaOCl 0.525%-Epimax for S. aureus (P = 0.043) and P. aeruginosa (P = 0.046) after 5 min. Furthermore, there was a meaningful difference between disinfection effects of Epimax-Deconex (P = 0.034) and NaOCl 0.525%-Epimax (P = 0.034) for P. aeruginosa after 10 min.

Conclusion:

Condensational silicone can be effectively disinfected by spraying tested three disinfecting agents. More specifically, Deconex showed the best results compared to the other agents.Key Words: Condensational silicone, disinfection, impression materials, spray  相似文献   
73.
Various studies have described glycyrrhizin (GL), an active triterpenoic saponin extract of licorice roots, as an anti-inflammatory, antiviral, antimicrobial, anti-tumor and immunomodulating agent. The activity of GL has been mainly attributed to its metabolites, 18-alpha (GA) and 18-beta-glycyrrhetinic acid (GB), which their mechanism of action on the immune system cells is not clearly known. In this study, we have investigated the effects of GA and GB on the immune system by targeting dendritic cells and analyzing phenotypic and functional maturity of murine dendritic cells (DCs) after treatment with these components. Stimulation of DCs with GA and GB resulted in up-regulation of CD40, CD86 and MHC-II molecules indicating their effects on the maturation of DCs. These components induced the allogenic immunostimulatory capacity of DCs by stimulating the proliferation of T cells and production of the T helper (h)1-promoting cytokine, IL-12. They also increased the production of IFN-γ by T cells in mixed-lymphocyte reaction. In conclusion, these results indicate that GA and GB may insert their immunomodulatory effects by enhancing DC maturation and modulating Th1/Th2 response through an increase in Th1 responses, implying their beneficial in host defense against infectious diseases.  相似文献   
74.
International Journal of Clinical Pharmacy - Background Patients with mitral valve stenosis have increased heart rate. HR reduction is known as an important treatment and therapy strategy for...  相似文献   
75.
Objective: To investigate the effect of hydro-ethanolic extract of Zataria multiflora (Z. multiflora) on endothelin level, total and differential white blood cells (WBC) count of sensitized guinea pigs. Methods: Five groups of guinea pigs sensitized to ovalbumin (OA) were given drinking water alone (group S), drinking water containing three concentrations of Z. multiflora (0.2, 0.4 and 0.8 mg/mL as groups S+Z1, S+Z2 and S+Z3) and dexamethasone (group S+D), n=6 for each group. The endothelin levels as well as total and differential WBC count in blood of sensitized and control guinea pigs were evaluated using enzyme linked immunosorbent assay method, and hemocytometer and Wright-Giemsa''s staining of blood sample smear respectively. Results: Blood endothelin levels, total and most differential WBC count were increased but lymphocytes decreased in sensitized animals compared to controls (all P<0.01). In groups S+D, S+Z2 and S+Z3 endothelin level, total and differential WBC counts were significantly improved compared with group S (P<0.01). Although, all measured parameters in group S+Z1 was lower than group S+D (P<0.01), some parameters in group S+Z3 were greater than in group S+D (P<0.05 to P<0.01). Conclusion: The results showed an anti-inflammatory effect of Z. multiflora extract in sensitized guinea pigs, which may suggest a therapeutic potential for the plant on asthma.  相似文献   
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78.
Abstract – Aims: The aim of this study was to retrospectively evaluate iatrogenic dental root damage, caused by two different techniques that utilized bone anchor screws, for intermaxillary fixation (IMF) in orofacial trauma. Materials and methods: The techniques used included either predrilled or drill‐free bone anchor screws. A total of 123 patients who required IMF were evaluated (97 men and 26 women). Sixty‐four patients were treated in the predrilled group, and 59 patients were treated in the drill‐free group. The data were collected over an 8‐year period and were analyzed using crosstabs and Fisher’s exact test. Results: Injuries to dental roots were found only in the predrilled group. Twenty‐nine patients (45.3%) were injured at the time of surgery. One year after surgery, 10 patients (15.6%) had permanently injured dental roots. There was a significant difference in injury rates between the predrilled and drill‐free groups 1 year after surgery (P < 0.001). Conclusion: There is an increased potential risk of iatrogenic injury and permanent damage to the dental roots when a technique that involves predrilled holes for bone anchor screws is used.  相似文献   
79.
Objectives: We studied the association between the prooxidant-antioxidant balance (PAB), anti-malondialdehyde-modified low-density lipoprotein (oxidized LDL, ox-LDL) IgG antibody and indices of cardiac function (systolic and diastolic function) in patients with coronary artery disease (CAD). Methods: Fifty-five patients with established CAD were selected, and serum levels of anti-ox-LDL IgG and PAB values were measured and compared with 40 matched healthy controls. Systolic and diastolic functions were determined for all patients. Results: PAB values were significantly higher in patients than in controls (p < 0.001), whilst serum anti-ox-LDL concentrations were not statistically different between the 2 groups (p = 0.821). However, after adjustment for high-density lipoprotein cholesterol, the patients had higher anti-ox-LDL levels (p = 0.04). Total PAB values were inversely associated with ejection fraction (r = -0.326, p = 0.031), but this was not the case for anti-ox-LDL in either group (p > 0.05). Conclusion: Serum concentrations of a marker of oxidative stress (PAB values) are inversely associated with cardiac function. PAB is a relatively simple index that could be incorporated into risk assessment in CAD patients. Anti-ox-LDL IgG antibody concentration does not appear to reflect total oxidative stress as assessed by PAB.  相似文献   
80.
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