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Wear resistance of composites is important for preservation of masticatory ability and vertical height. The aim of this study was to compare wear resistance of two laboratory type composites and one direct composite. In this in vitro study 5 samples from each type of composites (SR Adoro, GC gradia, Clearfil ST) was prepared in incremental technique. Exposure time was 40 seconds and thickness of layers was 1 mm. Wearing load was 6kg and applied via pressable chromium cobalt bar (1.98 mm2 tip) at 5000, 20000, 80000, 120000 cycles. Pre and post wearing samples weight was measured by an electronical weight balance with 0.0001 gr accuracy. The data was compared. There was significant decrease in weight of all type of composites from initial weight to 120000 cycles (p≤0.001). (GC gradia 4.42±1.26mg, SR Adoro 6.5±0.89mg, Clearfil ST 4.52±2.14mg). Although after applying all wearing cycles the average decrease of weight was smaller in GC gradia rather than Clearfil St that smaller than SR Adoro, however there was no significant difference. GC gradia and Clearfil ST showed less wear than SR Adoro. There was significant wear in all types of composites in wearing cycles.

Previous studies were carried out on blood subjects with migraine. Blood calcium and magnesium don’t reflect the body content of it. This research was designed to measure intra cellular magnesium and calcium concentration. The aim of this study was to measure red blood cell magnesium and calcium in patients with migraine. In this research Red blood cell magnesium and calcium concentration were measured in 21 patients with migraine and 24 normal subjects without migraine. Magnesium and calcium levels were determined by atomic absorption. In this study differences between the magnesium and calcium levels in the two study groups were found. In comparison with normal subjects, migraine patients had higher red blood cell magnesium levels (8.409 ± 0.516, 7.866 ±0.687 mg/ml, p>0.05). Also, In comparison with normal subjects, migraine patients had higher red blood cell calcium levels (14.255 ±0.453, 3.799 ±0.176 mg/ml, p<0.05). The data were expressed as the mean ± the standard deviation, and they were statistically analyzed with Student t-test. Change calcium, magnesium level in migraine agreement with previous studies of a possible role for magnesium and calcium in migraine patients. Therefore, according to our data changing magnesium and calcium levels is related to migraine pathophysiology. In future with control calcium and magnesium level in migraine patients, we can use for improving the status.

There is not a suitable marker in dilution method in analysis of biomarker in joint fluid. In past, dye dilution method was used for joint fluid, but there were some errors. The aim of this work is the use of rate change lactate level in serum and synovial fluid of patients with arthritis by application of dilution method and direct aspiration as a biomarker. In this cross-sectional study synovial fluid were obtained from 30 arthritis patients by direct aspiration. Also, serum sample were obtained from these patients. Serum and synovial fluid Lactate level was measured by standard biochemical methods. For analysis results Students t-test was used and P was less than 0.05. Lactate concentration increases in synovial fluid (14.1 ±2.3 mg/dl) in compare with serum (12.9 ± 2.1 mg/dl), but the differences were not significant.(p>0.05). The difference between lactate concentration in synovial fluid and serum is not significant. The rate change of lactate concentrations in synovial fluid and serum was stable.

Previous reports show that phosphorylation anddephosphorylation mechanisms involve in regulation of sialyl transferaseactivity. The aim of this research was to study sialyl trnsferase activity with phosphorylation and dephosphorylation mechanisms. This experimental trial study performed on 25 rats without signs of illness. Rat brains were pulled out and brain homogenization was done and then sialyl transferase purified purified from rat brain. Homogenization of rat brain is performed in the cephadex chromatography. We added protein kinaseokadaic acid and forbol to different groups. Data were statistically analyzed using SPSS soft wave. Results showed a significant increase in sialyl transferase activity in the control group, comparing with protein kinase C and okadaic acid groups.Results showed a significant decrease in sialyl transferase activity incontrol group, comparing with protein phosphatase and forbol groups. Our findings show that sialyl transferase of rat brain with protein kinase decreases enzyme activity and these results were in accordance with other studies in this respect. We found that treatment of rat brain sialyl transferase by protein phosphatase increases its activity.

Considering the importance of serum paraoxonase (PON1) in preventing from production of oxidized low-density lipoprotein (LDL), and consequently, its role in prohibiting from development of atherosclerosis, we investigated paraoxonase and arylesterase activities of PON1 in patients with coronary artery disease (CAD) and with different coronary stenosis. In the present study, 120 patients with CAD were examined and their stenosis documented by coronary angiography. Then, the patients were divided into two groups: 60 patients with less than 50% of stenosis and 60 patients with more than 70% of stenosis. Paraoxonase and arylesterase activity was measured with substrates of paraoxon and phenylacetate, respectively. The effects of eight drugs, which are prescribed in cardiovascular diseases, were assayed on paraoxonase activity. There were no significant differences in LDL-C, total cholesterol and triglyceride levels between two groups, but HDL levels in patients with >70% of stenosis were significantly decreased as compared with those of patients who had <50% of stenosis (P<0.03). Both paraoxonase and arylesterase activity in patients with >70% of stenosis were significantly lower (P<0.05) than patients with<50% of stenosis. Paraoxonase and arylesterase activities of PON1 and HDL levels in patients with >70% of stenosis were lower than patients with <50% of stenosis. In other words, the PON1 activities and HDL levels decrease with progression of atheroma. Therefore, the study might support the important role of HDL-bound PON1 in preventing from formation of ox-LDL and its anti-atherogenic activity.

Free radicals are cytotoxic and can act as inflammatory mediators it seemed useful to investigate whether ploymethyl methacrylate used in complete dentures induces the release of free radicals. The aim of the present study was to compare the free radical concentration in saliva before and after use of acrylic denture. Methods & Subjects: In this experimental study 50 healthy human subjects who were wearing recently made heat polmerized ploymethyl methacrylate dentures were selected and saliva samples were taken before and after use of dentures. Free radicals concentration was measured by spectrophotometry method. Data were analyzed by student t-test. Results showed that the mean concentration of free radical in the after time of delivery of prosthesis (1.150.18 ngr/l) significantly increased when compared with start time (0.60.13 ngr/l). Mean concentration of free radical in the after time of delivery of prosthesis was increased (1 day, 1 week, 1 month after delivery of prosthesis). The increase was significant (P<0.05). Free radicals were produced in saliva after use of acrylic dentures.

Due to volatile property of monomer from Methylmethacrylate and its well known toxic side effects, in case of absorption via skin or respiratory system. Also, due to allergic reactions of it, consideration of suitable ventilation systems and using protective methods is very important. To decrease direct contact with it, the capabilities of technician and improves his health and work place, we investigate relationship between Methanol level and exposure to Methylmethacrylate. In a case-control (In vivo) study of 32 dental laboratory technicians in Babol and Sari before and after working and 32 normal subjects, urine samples were collected. Urine Methanol levels were analyzed by paper and gas chromatography. Mean concentration of Methanol in case group (1.2 micro mol/l) was significantly more than control group (0.78 micro mol/l). Also, Methanol level was significantly higher after work (1.45 micro mol/l) when compared to before work (1.27 micro mol/l), (P<0.05). No relation between work history and urine Methanol level was observed. Due to significant increase of Methanol concentration during work in work place, the use of protective methods such as suitable ventilation, wearing mask and gloves, also, using vapor absorbing tubes can be useful in increasing dental laboratory workplace safety.

3 beta-Hydroxy-Delta-5-steroid dehydrogenase is an important key anzyme of steroid hormone biosynthesis, which is involved in catalyzing the conversion of pregnenolone to progesterone in the biosynthesis of steroid sex hormones. This complex enzyme is the second enzyme in the steroid hormone biosynthesis pathway and it is identified as an autoantigenic target. In this study, a simple method is presented for the quantitative assay of 3β-Hydroxy steroid dehydrogenase activity in testis of rat. An excess of pregnenolone was incubated with several concentrations of whole testis homogenate. The reaction mixture containing the pregnenolone, NAD, isonitrotetrazolium in 0.15 M Tris-HCL buffer(PH=8) and the enzyme extract from testis of rat was incubated for 1.5 at 37˚c. Absorbance at 495 nm was read in a spectrophotometer. The results showed that 3-β-hydroxy steroid dehydrogenase activity was linear with time and protein concentration. The present method can easily be performed and is sensitive enough to assay 3-β-hydroxy steroid dehydrogenase activity in rat testis.

Statement of Problem: Changes in protein levels, host calls enzymes and inflammatory mediators in gingival crevicular Fluid (GCF) are considered as diagnostic indicators of Periodontitis. he aim of the present study was to measure the elastase enzyme activity in gingival crevicular Fluid among patients with periodontitis. In this study, 52 periodontitis patients (experimental group) and 51 healthy subjects without any gingival inflammatio (control group) were participated. Subjects of the periodontitis group showed pockets of 4-5 mm depth without gingival enlargement and recession or pockets of 1-2 mm depth with gingival recession. For enzyme activity measurement, lOOu,! of gingival fluid of each sample was mixed with lOOu! of enzyme substrate on the tube. The mixture was incubated at 34°c for lh with a buffer solution of 1ml volume and absorbance was read at 410nm with spectrophotometer. The enzyme activity differences between two groups were analyzed by student t test. The elastase enzyme activity in gingival crevicular fluid in subjects with periodontium destruction and control subjects was 153±11.3 and 52.7±10.4 enzyme unit in ml per minute, respectively. The difference between groups was statistically significant (PO.05). Based on the findings of this study, the measurement of elastae enzyme activity could be a useful indication of tissue changes that may ultimately manifest clinically as periodontitis.

3 Beta-Hydroxy-delta-5-steroid dehydrogenase is an important key enzyme of steroid hormone biosynthesis, which is involved in catalyzing the conversion of pregnenolone to progesterone in the biosynthesis of steroid sex hormones. This is the fourth enzyme in the steroid hormone biosynthesis pathway to be identified as an autoantigenic target. Pregnenolone is incubated with several concentrations of whole testis homogenate. The reaction mixture containing the pregnenolone, NAD and iodonitrotetrazolium in 0.15 M Tris-HCL buffer (pH=7.7) and the enzyme extract from testis of rat was incubated for 1.5 h at 36°C. Absorbance at 495 nm was determined by a spectrophotometer. pH optimum and time incubation for this enzyme was 7.99 and 1.5 h respectively. The Kmax was 5.3×10^-6 and Vmax was 3.11×10^-6 nmol/mg/min. Our results were in good agreement with those reported previously.

The use of immunoglobulin Y (IgY) instead of polyclonal antibodies prepared in mammals has been reported recently. These antibodies are found to have better properties in terms of specificity and ease of large scale production. In this study, proteins from egg yolk were extracted with acid and chloroform. The result of cellulose acetate electrophoresis at pH 9 showed some extra bands which were further purified with sodium sulfate precipitation (20%). The purified band was observed in the y globulin region. SDS-PAGE eletrophoresis of the product showed impurities which were removed by T-gel chromatography. Following that only H-chainof immunoglobulin Y with a molecular weight of about 66 KD was observed. Using the above procedure, a yield of around 40.7 mg IgY / egg was obtained.

Sialoprotein is one of the most abundant non-collageneous and phosphorylated glycoproteins in human. This protein plays an important role in the structure of human teeth. The aim of this project is to measure the amount of dentin Sialoprotein in the healthy and decay teeth to evaluate the variation in the teeth structure. In this investigation 50 decay teeth has been collected from patients referred to the clinic. The dentin was separated and placed in liquid Nitrogen. One gram of each dentin was washed with distilled water for 30 mins and subsequently the dentin was powdered, and relocated to the gaunidin-Hcl tris buffer, and incubated at 4°C for 48 hrs. The dentin powder was centrifuged at 3000 g for 20 mine. The supernatant was discarded, and the samples again was centrifuged at 10000 g. Finally one ml of this supernatant transferred to the sepharose column and washed with gaunidin-Hcl tris at 1 ml/min. The fractions obtained by chromatography was monitored by electrophoresis. The amount of decay teeth Sialoprotein was 17.23±1.45 ng/l and in the healthy teeth was 26.39±4.27 ng/l. The results from this study indicate that the Sialoprotein content in patient dentin decreased by about 1.5 time compared normal subjects.

Adenylyl cyclase is a membrane-bound enzyme that catalyzes the conversion of ATP to cAMP. The inhibition of adenylyl cyclase was carried out by measuring the ability of the macrophage chemotactic protein-1 to inhibit the forskolin-induced enzyme activity. Measurement of adenylyl cyclase activity was performed according to the procedure described by Wiegn.Adenylyl cyclase activity in the present macrophage chemotactic protein-1 was decreased compared to that in controls [2.11+/- 0.15(mean +/-SD.)vs. 6.83+/-0.45, activity (µ mol cAMP/mg protein/min)].Macrophage chemotactic protein significant reduced adenylyl cyclase activity by 79.9%.

Background-Chitosan, a polymer of glucosamine, appears to interact with bile acids and/or lipids in the intestinal lumen. As it is well established that the ingestion of some types of dietary fibers has been shown to influence lipid levels, it appears possible that chitosan may also influence protein metabolism.Methods-In the present study, we investigated the effect of chitosan on nitrogen metabolite concentrations in mice. Mice in the treatment group received 10 mg chitosan orally 2 times a day for 21 days. Serum urea and creatinine levels were measured in the test and control groups.Results-In the chitosan-treated group, serum creatinine levels were lower as compared to controls [0.63±0.13 (mean±SD, n=90) vs. 1.14 ± 0.21 mg/dl]. A significant decrease in average serum urea level was also observed after 28 days of chitosan ingestion by the mice in the treatment group [27.45±2.53 (mean±SD, n=90) vs. 39.68±2.47 mg/dl].Conclusion- Daily consumption of chitosan significantly reduced the serum creatinine and urea levels in mice, although there are no confirmed explanations for these effects. This work also provides an insight to the perspectives for using chitosan in clinical practice.