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Objective@#To evaluate the bond performance of primers, universal adhesives and self-adhesive resin cements containing methacryloyloxydecyl dihydrogen phosphate (MDP) to zirconia.@*Methods@#Two hundred and ten yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) plates were prepared and divided into seven groups according to each of six MDP-containing products and one MDP-free resin cement. Two primers, two universal adhesives and two self-adhesive resin cements were applied on the specimens after these specimens recived alumina air abrasion. The group of MDP-free resin cement was set as control. Each group contained 30 specimens. Y-TZP plates were bonded to resin composite to build resin bonding specimens, and half of these plates were stored in distilled water at 37 ℃ for 24 hours, the other half were stored for 12 months. Shear bond strength (SBS) test and fracture modes analysis were performed.@*Results@#The SBS values of all the experimental groups were above 9.51 MPa, which increased 24-hour values compared to the (5.04±0.50) MPa of the control group. Group using one of the self-adhesive resin cement yielded the highest SBS, (11.06±0.84) MPa. SBS of all groups decreased significantly compared to 24-hour SBS after aging (P<0.05), however, the SBS values of MDP-containing products groups can still be maintained above 7.44 MPa. Two self-adhesive cement groups and one of the universal adhesive group maintained higher SBS values, and the values were statistical different from those from the two primer groups (P<0.05) .@*Conclusions@#Different MDP-containing products have different effects on the bond durability of zirconia.
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BACKGROUND:Although incidents of organophosphate-induced delayed neurotoxicity have been documented for over a century, the molecular mechanisms underlying the axonopathy remain poorly understood. OBJECTIVE:To discuss the effects of tri-ortho-cresyl phosphate (TOCP) on homeostasis of the glutamate-glutamine cycle and the expression of key enzymes in the brains of hens. METHODS:Twenty-four adult hens were randomly divided into three groups (n=8). TOCP group was treated with TOCP by gavage at a single dosage of 1 000 mg/kg, and control group was given an equivalent volume vehicle by gavage, while hens in the phenylmethylsulfonyl fluoride (PMSF)+TOCP group were subcutaneously injected with 40 mg/kg PMSF fol owed by 1 000 mg/kg TOCP 24 hours later. The hens were kil ed on days 5 and 21 post-dosing. The brains were taken out quickly and preserved in a-80℃deep freezer. ELISA was used to determination the content of glutamine synthetase and glutaminase and the activity of glutamine synthetase. Corresponding kits were used to measure the level of glutamate and glutamine. Fluo3-AM was used to measure cytosolic calcium concentration. RESULTS AND CONCLUSION:The activity and content of glutamine synthetase and the concentration of glutamine were down-regulated, while the concentrations of the intracellular Ca2+and glutamate were up-regulated in the early stage after TOCP administration. It is also suggested that the downregulated expression of glutamine synthetase may be associated with organophosphate-induced delayed neurotoxicity through the disruption of homeostasis of the glutamate-glutamine cycle and cytosolic calcium concentration.
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Objective To investigate whether AZD1152 (AZD),the selective inhibitor of aurora kinase B,may play a role in the treatment of cisplatin-resistant ovarian carcinoma when administrated alone or in combination with cisplatin.Methods Hey (cisplatin-resistant ovarian cancer cell line) cells were analyzed.According to the treatment plan,Hey cells were divided into four groups (AZD group,cisplatin group,AZD + cisplatin group and control group).Methyl thiazolyl tetrazolium (MTT) assay was used to test the cells proliferation,caspase-3/7 activity analysis was used to analyze cells apoptosis,and fluorescence insitu hybridization (FISH) assay was used to determine the copy the number of chromosome 7 and checked the copy numbers of hTERC gene and C-myc gene.Results MTT test showed that proliferation of AZD group was lower than that in control group(P ＜ 0.01).The cells proliferation with the treatment with 10 and 20 nmol/L AZD for 24 hours was (81.4 ± 3.6)％ and (81.4 ± 3.6)％ respectively,and the cells proliferation for 48 hours was (43.1 ± 2.0) ％ and (38.5 ± 1.6) ％ respectively,which was significantly lower than control group (100％,P ＜ 0.01) ; Treated with the same concentration of AZD,inhibition of proliferation was significantly enhanced as the time extended (P ＜ 0.01).Proliferation in group AZD+cisplatin was lower than that in cisplatin group (P ＜ 0.01) which suggest that there were additive effects after combined AZD with cisplatin.Compared with control group,caspase-3/7 activity in AZD group increased significantly (P =0.000),and the same results was seen between AZD ± cisplatin group and cisplatin group or AZD group (all P ＜ 0.01).Compared with cisplatin group or control group,the copy numbers of hTERC,C-myc and the number of chromosome were significantly increased in AZD group and AZD + cisplat group (all P ＜ 0.05).Conclusions AZD could inhibite ovarian cancer cells proliferation and induce cells apoptosis significantly.AZD alone or in combination with cisplatin may result in the increased cells polyploidy.
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PURPOSE: The optimal dose of oximes for use in the treatment of organophosphorus pesticide poisoning has not been conclusively established. In this retrospective study, we assessed the effectiveness of the use of high-dose pralidoxime infusion in treating organophosphorus pesticide poisoning. METHODS: From January 1998 to December 2009, 71 patients visited the hospital Emergency Department (ED) as a result of organophosphate pesticide intoxication. All of these patients received an initial bolus of 2 g of pralidoxime as the first step of treatment. Patients who then received continuous infusion of pralidoxime at a dose of 500 mg/hr were entered into study group 1 (low dose), and those treated by continuous infusion of pralidoxime at a dose of 1000 mg/hr were entered into study group 2 (high-dose). Plasma cholinesterase activities for each patient were evaluated at ED arrival and re-evaluated 24 hours after pralidoxime infusion. The effectiveness of the two treatment modalities was gauged by comparing the required duration of mechanical ventilation, time spent in the intensive care unit (ICU) and total time spent in the hospital. RESULTS: The mean duration of mechanical ventilation was 9.98+/-6.47 days for group 1 and 4.39+/-6.44 days for group 2. The respective mean duration of time spent in ICU and the total number of days in the hospital were 16.38+/-18.84 days and 21.87+/-20.16 days for group 1, and 7.83+/-9.99 days and 11.71+/-13.53 days for group 2. High-dose pralidoxime treatment was associated with shorter required durations for mechanical ventilation, ICU and hospital stay. In addition, plasma cholinesterase reactivation rates were higher for those patients receiving high-dose pralidoxime treatment. CONCLUSION: The results suggest that high-dose pralidoxime treatment has greater efficacy for patients suffering from organophosphorus pesticide poisoning.
Subject(s)
Humans , Cholinesterases , Emergencies , Intensive Care Units , Length of Stay , Organophosphates , Oximes , Plasma , Pralidoxime Compounds , Resin Cements , Respiration, Artificial , Retrospective Studies , Stress, PsychologicalABSTRACT
PURPOSE: Although, there have been many reports about factors involved in the severity and prognosis of organophosphate toxicity, there are few reports on integrated application of scoring methods using those factors for prognosis. Our report is about the possible application of such scoring methods in the early stage of organophosphate intoxication. METHODS: This study included organophosphate intoxication patients who were admitted to the Emergency department (ED) between March 1, 2004 and February 28, 2008. We limited enrolment in the study to patients who had required assisted mechanical ventilation and used atropine for therapy. This was a retrospective study about age, drug toxicity, mental status, existence of metabolic acidosis and QT prolongation for each patient. RESULTS: Thirty seven patients were enrolled in this study. Among the 37, 22 survived and 15 died. For survivors, drug toxicity and mental status were correlated with total dose of atropine, and the existence of metabolic acidosis was correlated with the duration of mechanical ventilation. Survivors had lower total scores than non-survivors. CONCLUSION: Application of scoring methods that include five factors (age, drug toxicity, mental status, existence of metabolic acidosis, existence of QTc prolongation) when acute, severe, organophosphate poisoning patients arrive at an ED can be helpful for their prognosis.