ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of Chaiqin Chengqi Decoction (,CQCQD) on cholecystokinin receptor 1 (CCKR1)-mediated signal transduction of pancreatic acinar cell in rats with acute necrotic pancreatitis (ANP).</p><p><b>METHODS</b>Twenty-seven Sprague-Dawley rats were randomized into three groups: the control group, the ANP group, and the CQCQD group (9 in each group). ANP rats were induced by two intraperitoneal injections of 8% L-arginine (pH=7.0, 4.4 g/kg) over a 2-h period. Rats were treated with 1.5 mL/100 g body weight of CQCQD (CQCQD group) or physiological saline (control and ANP groups) at 2 h interval. And 6 h after induction, pancreatic tissues were collected for histopathological examination. Pancreatic acinar cells were isolated for determination of CCKR1 mRNA and protein expression, phospholipase C (PLC) and inositol-1,4,5-triphosphate (IP3), and determination of fluorescence intensity (FI) as a measure of intracellular calcium ion concentration [Ca(2+)]i.</p><p><b>RESULTS</b>The pancreatic histopathological score (6.2 ± 1.1) and the levels of PLC (1,187.2 ± 228.2 μg/mL) and IP3 (872.2 ± 88.4 μg/mL) of acinar cells in the ANP group were higher than those in the control (2.8 ± 0.4, 682.5 ± 121.8 μg/mL, 518.4 ± 115.8 μg/mL) and the CQCQD (3.8 ± 0.8, 905.3 ± 78.5 μg/mL, 611.0 ± 42.5 μg/mL) groups (P<0.05). [Ca(2+)]i FI for the ANP group (34.8±27.0) was higher than that in the control (5.1 ± 2.2) and CQCQD (12.6 ± 2.5) groups (P<0.05). The expression of pancreatic acinar cell CCKR1 mRNA in the ANP group was up-regulated (expression ratio=1.761; P=0.024) compared with the control group. The expression of pancreatic acinar cell CCKR1 mRNA in the CQCQD group was down-regulated (expression ratio=0.311; P=0.035) compared with the ANP group. The ratio of gray values of the CCKR1 and β-actin in the ANP group (1.43 ± 0.17) was higher than those in the control (0.70 ± 0.15) and CQCQD (0.79 ± 0.11) groups (P<0.05).</p><p><b>CONCLUSIONS</b>Pancreatic acinar cell calcium overload of ANP induced by L-arginine was related to the up-regulated expressions of pancreatic acinar cell CCKR1 mRNA and protein. CQCQD can down-regulate expressions of pancreatic acinar cell CCKR1 mRNA and protein to reduce the PLC and IP3 of pancreatic acinar cells, relieving the calcium overload and reducing the pathological changes in rats with ANP.</p>
Subject(s)
Animals , Acinar Cells , Metabolism , Blotting, Western , Calcium , Metabolism , Drugs, Chinese Herbal , Pharmacology , Therapeutic Uses , Fluorescence , Gene Expression Regulation , Inositol 1,4,5-Trisphosphate , Metabolism , Pancreas , Pathology , Pancreatitis, Acute Necrotizing , Drug Therapy , Pathology , RNA, Messenger , Genetics , Metabolism , Rats, Sprague-Dawley , Receptors, Cholecystokinin , Genetics , Metabolism , Signal Transduction , Type C Phospholipases , MetabolismABSTRACT
Objective To work out the suitable iodine content in iodized salt among general population in Enshi Autonomous prefecture,Hubei province by determination of the iodine content in salt.Methods The method of direct titration was used to determine the iodine content in salt samples collected from residents in natural villages sampled from four directions of east,west,south and north in each township which was sampled from five directions of east,west,south,north and center in each city(county) in Enshi Autonomous prefecture,and salt samples were collected in Hubei Salt Industry Group Co.,Limited.Enshi Branch in 2011.The method of three-days weighing was used to estimate the resident's daily per capita intake of iodized salt.The appropriate iodine content for general population in salt was worked out according to the iodine content in salt from households and enterprises in Enshi Autonomous prefecture,the amount of iodine loss in iodized salt,the amount of per capita daily intake of iodized salt and the national iodine nutrition monitoring results.Results The median of iodine content in salt from residents and the production enterprises in 2011 was 33.5 mg/kg and 34.7 mg/kg,respectively.The residents' per capita salt intake was 10.9 g,actual intake of iodine wss 335.0 μg/d.Iodine content in iodized salt was 20 mg/kg ±30％ for the general population,actual intake of iodine was 149.4-250.4 μg/d.Conclusions The residents iodine intake is higher in Enshi Autonomous prefecture.Considering the comprehensive factors,including food iodine,water iodine,and iodine cooking loss,that affect the intake of salt iodine,the appropriate iodine content in iodized salt is 20 mg/kg ± 30％ for the general population.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate fracture resistance of metal-ceramic crown restored incisors with different post-and-core systems.</p><p><b>METHODS</b>Selected 40 intact maxillary central incisors were endodontically treated and then randomly assigned to four groups of 10 teeth each. Teeth in Group A were prepared to root canal with 10 mm in length, 1.6 mm in diameter and restored with fiber-reinforced posts and composite cores. Same final preparation but root canal with 1.5 mm in diameter was achieved for teeth in the other three groups. Teeth in Group B were restored with prefabricated titanium alloy posts and composite cores and teeth in Group C were restored with cast nickel-chromium post-cores. The posts were luted with a composite resin luting system, and metal-ceramic crowns were restored and cemented with the same luting system for all of the teeth in Group A, B and C. The other 10 teeth were restored with cast nickel-chromium post-cores and metal-ceramic crowns as a control, which were cemented with glass-ionomer cement. All restored teeth were thermo-cycled for 5000 cycles (5 degrees C/55 degrees C) as a fatigue test. The tooth was loaded in a universal testing machine at an angle of 135 degrees to the long-axis at the incisal edge with a cross-head speed of 1.5 mm/min until fracture. Fracture loads (N) and modes (repairable or catastrophic) were recorded. One-way ANOVA and SNK test were used to determine the significance of the failure loads between groups. Chi-square test was conducted for evaluation of the fracture mode.</p><p><b>RESULTS</b>The fracture loads from Group A, B, C and control group were (534.4 +/- 145.7) N, (499.8 +/- 168.9) N, (412.6 +/- 99.3) N, (337.4 +/- 121.2) N, respectively. A significant difference was existed among four groups (P < 0.05). The fracture loads of Group A and Group B were significantly higher than control group (P < 0.05). The repairable mode of fracture observed from Group A to control group was 80%, 40%, 20% and 30%, Group A had a significantly higher number of repairable fractures than those of the other groups (P < 0.05).</p><p><b>CONCLUSIONS</b>Within the limitations of this study, fiber-reinforced post has an excellent fracture resistance, and can be recommended as an alternative to cast post-cores, especially for incisor esthetic restoration.</p>
Subject(s)
Adult , Humans , Middle Aged , Crowns , Dental Stress Analysis , Incisor , Metal Ceramic Alloys , Post and Core Technique , Shear StrengthABSTRACT
<p><b>OBJECTIVE</b>To compare the mechanical properties of different phase transformation of nickel-titanium orthodontic archwires.</p><p><b>METHODS</b>Nickel-titanium orthodontic archwires with same-sized (0.016") but different phase transformation were examined using a three-point bend test. Samples were tested at same conditions and oral temperature(37 degree), but in different utmost strain capacity, then the strain-stress chart was obtained, the phase transformation point (Af) was also examined.</p><p><b>RESULT</b>The wires of the highest phase transformation point had the least orthodontic force; on the contrast the least phase transformation point had the highest orthodontic force at 3.0 mm utmost strain capacity. The orthodontic forces were not different at the little strain capacity (P >0.05), but which was significantly different adove the 0.5 mm (P<0.05), which was same as 3.0 mm.</p><p><b>CONCLUSION</b>The nickel-titanium orthodontic archwires with high level of phase transformation have low orthodontic forces and more stability.</p>
Subject(s)
Humans , Materials Testing , Methods , Nickel , Orthodontic Wires , Reference Standards , Stress, Mechanical , Tensile Strength , TitaniumABSTRACT
<p><b>OBJECTIVE</b>To investigate calcium-phosphate coating on commercial pure titanium substrate using a fast biomimetic procedure.</p><p><b>METHODS</b>The titanium specimens were divided into two groups, group A and group B. The specimens of group A were only treated with the mixture of H2SO4/HCl for 30 min. The specimens of group B were treated with the mixture of H2SO4/HCl for 30 min, immersed into 5 mol/L NaOH solution at 60 degrees C for 24 h, and then heated to 600 degrees C and maintained for 1 h. All specimens were soaked into simulated body fluid-A (SBF) and SBF-B for each day. The surface morphology was observed by field scanning electron microscopy.</p><p><b>RESULTS</b>Dense calcium-phosphate coating deposited on all the titanium surfaces of two groups. The calcium-phosphate coating consisted of spheric structure with a diameter of 1 approximately 3 microm, which was proved to be hydroxycarbonate apatite with the analysis of X-ray diffraction.</p><p><b>CONCLUSIONS</b>Thin hydroxycarbonate apatite coating can deposited on pure titanium using a fast biomimetic procedure.</p>