Introduction: Periodontitis is a chronic multi-factorial infectious disease characterized by irreversible destruction of collagen fibers and other matrix constituents of the gingival tissues and periodontal ligament, and resorption of alveolar bone around the teeth with periodontal pocket formation. Host response to periodontal disease includes production of different enzymes that are released by stromal, epithelial or inflammatory cells associated with cell injury and cell death, including aspartate aminotransferase and lactate dehydrogenase. The aim of this study was to compare aspartate aminotransferase and lactate dehydrogenase salivary levels in patients with generalized aggressive periodontitis and chronic mild-to-moderate periodontitis and healthy subjects with normal periodontium.Materials and Methods: In this experimental study, unstimulated saliva of 25 patients with mild-tomoderate periodontitis, 15 patients with aggressive periodontitis, and 25 subjects with healthy gingiva were collected. The mean aspartate aminotransferase and lactate dehydrogenase salivary levels were measured by RA-ST autoanalyzer system. Data were analyzed by ANOVA and Tukey test.Results: The mean levels and standard deviations of lactate dehydrogenase salivary enzyme in generalized aggressive periodontitis, chronic mild-to-moderate periodontitis and control groups were 1713±88.4, 1492±65.4, 1108±34.5, respectively, with significant differences between the groups (p value<0.05) The mean levels and standard deviations of aspartate aminotransferase salivary enzyme in generalized aggressive periodontitis, chronic mild-to-moderate periodontitis and control groups were 55.46±5.6, 47.04±3.3 and 32.04±2.3, respectively, with significant differences (p value<0.05).Conclusion: Mean levels of aspartate aminotransferase and lactate dehydrogenase salivary enzymes in periodontal patients were higher than those in healthy subjects and these enzymes can be good markers for determining amount of destruction of periodontal tissues.

Introduction: Physical activity and age are among the factors affecting lactate levels and lactate dehydrogenase activity. Physical activity appears to be able to counterbalance the morphological and metabolic changes associated with aging that decrease physical ability and performance. The purpose of the present study was to assess the effects of interval training on blood lactate levels and lactate dehydrogenase activity in young and old rats Methods & Materials: A total of 40 male rats were selected and then divided into two age groups -the old group (20 rats aged 27 months and weighing 389±31 g) and the young group (20 rats aged 3 months and weighing 224±13 g). Each group was itself randomly divided into an experimental group (n=10) and a control group (n=10). The training protocol involved 4 minutes of running on the treadmill with intervals of 2 minutes active resting in 10 training bouts of 60 minutes, for 6 sessions per week and for 8 weeks and gradually increasing in intensity. Twenty-four hours after the last training session, the rats were anesthetized with a mixture of ketamine and xylazine in order for their blood sample to be collected from their cardiac puncture. Their lactate levels and LDH activity were then measured by an enzymatic method. Data were analyzed using the one-way ANOVA and Tukey's post-hoc test.Results: The results showed no significant differences in blood lactate levels between the four groups; however, LDH activity was significantly higher in the young experimental group than in the young control group (p<0.05).Conclusion: The results indicate that lactate is increasingly cleared by interval training. It also appears that the effect of training on lactate clearance is similar in both young age and old age. Monitoring blood lactate levels benefits muscle glycogen replenishment and intracellular pH (pHi) regulation.

The aim of this study was to assess the effects of intermittent training on lactate level and lactate dehydrogenase enzyme activity in Wistar rats. 20 male Wistar rats (mean age 3 months and weight 224± 14 g) were selected and randomly divided into the training (11=10) and control (11=10) groups. The training protocol consisted of running on a treadmill for 4 minutes and then 2 minutes of active rest in J 0 training phases for the experimental group. All rats were anesthetized with a mixture of ketarnine and xylazine 48 hours after the last training session after an overnight fasting. To measure lactate and LDH enzyme activity, blood samples were obtained from their cardiac puncture. Data were analyzed by mean and standard deviation (M±SD) and independent t test. The results showed no significant differences in blood lactate level between the two groups, but there was a significant difference in LOH enzyme activity between the two groups (P<0.05). These results indicate that intermittent training caused the clearance of lactate. Enhance of lactate replenished muscle glycogen and prevented H+ concentration which was produced along with lactate.

Background and aim: Measurement of serum enzymes levels, such as lactate dehydrogenaze (LDH) and its isoenzymes is a routine way for diagnosis of myocardial infarction. One of these isoenzymes is LDH-1 which is raised after myocardial infarction. The purpose of this study was to evaluate total-LDH/heat resistant-LDH ratio in patients with acute myocardial infarction and unstable pectoral angina. Methods: In an descriptive analitical study 220 patients with suspected myocardial infarction (MI) or unstable pectoral angina (UA), hospitalized in CCU ward of Ekbatan Hospital in Hamedan city were studied. Using WHO's criteria, 110 were classified as having myocardial infarction and 110 as having unstable pectoral angina. The serum level of total-LDH and heat resistant-LDH was measured by NADH exchange method, 24 to 48 hours after their admission to the hospital. Data were analyzed by student-t test and Mann-Witheny test. Result: Our study showed that total-LDH / heat resistant-LDH ratio in MI patients was 1.27±0.18 and it was 2.51±1.39 in UA patients (P<0.001). In our study, we found that when total LDH/ heat resistant-LDH ratio is decreased the severity of myocardial infarction (number of involved leads) and creatine phosphokinase (CPK) is increased (P<0.01). We did not find any relationship between total LDH/ heat resistant-LDH ratio with sex, age, type of MI (Q-wave & Non Q-wave), block after MI and arrhythmia following MI. Conclusion: Our results revealed that measuring heat resistant- LDH can be used as a method for accurate diagnosis of MI. This simple method can be used in centers where other accurate tests are not available.

Background & Aim: Levels of lactic dehydrogenase(LDH) in the cerebrospinal Fluid(CSF) have been used to evaluate a variety of neurologic disorders. However, few studies have been performed on neonates. The aim of this study was to detect levels of this enzyme in normal neonates.Patients and Methods: In this descriptive study, CSF samples were collected from 94 febrile infants; 46 aged 0-4 weeks and 48 aged 5-8 weeks. These LDH levels were compared to those of 45 febrile infants with mean age of 10±6/2 months who were suspected of nervous system infection and normal CSF findings.Results: Mean total LDH activity in the CSF was significantly higher in the first month of life than in the second month of life as compared with the control group (p<0.001).Conclusion: We propose evaluation of total LDH activity in CSF of normal neonates according to age.

Aims: increasing applications of electric and electromagnetic fields have caused some anxieties in human health. This research work has been done on the effects of 0.04 T and 0.06 T intensities with 50HZ frequency in lactatdehydrogenase and glucose concentration of adult NMRI mice. In this work solenoid coils to produce electromagnetic fields were used two experimented groups (n=12) were exosed to electromagnetic wave four hours a day for 28 days. The results of experimental groups were compared with sham groups (n=6) and controls (n=6). Electromagnetic investigation of transaminase showed significant increase of lactatdehydrogenase (p<0.05) in 0.06, 0.04 mT electromagnetic field compared with sham and control groups. The amount of glucose concentration decreased at the same field significantly (p<0.05). Results of this research work showed electromagnetic field caused effect on the lactatdehydrogenase and glucose concentration.

Silver nanoparticles because of their antibacterial properties have become one of the most widely used combinations of nanomaterial and due to the development of nanoparticles, there are the risks of releasing of such materials to the environment from products containing them. In this study, six types of a filter containing silver nanoparticles containing 0. 25, 0. 5 and 1 percentage nanosilver with and without Aminopropyl triethoxysilane is used to control the Saprolegnia fungus in Persian sturgeon egg incubators. Two of six filters contain one percentage of silver nanoparticles could prevent Saprolegnia fungus completely as the optimal filter. The effects of these two types of optimized filters on embryos of Persian sturgeon kept in the incubator examined by studying the changes of some oxidative enzymes including glutathione peroxidase and lactate dehydrogenase and also by studying lactate changes by HNMR, in the second and fourth days of the incubation period. The results showed that the use of filters containing silver nanoparticles due to the release of silver from the filter into the water reduced glutathione peroxidase in both sampling days and reduced lactate and lactate dehydrogenase in second incubation day and increased them in the fourth day. So measuring these enzymes is a good biomarker for early assessment of those intracellular changes in fish that are affected by such filters.

Background: Inflammatory enzymes and free radicals are important factors affecting the immune system. However, there seems to be no detailed information about the extent to which these factors can affect superoxide dismutase 1 gene expression in female athletes, especially in incremental exercises. Therefore, the aim of the present study was to investigate the correlation between superoxide dismutase 1 gene expression with lactate dehydrogenase (LDH) and free radicals in female athletes after an incremental intensity exercise.Methods: Fifteen 22-24 year old female athletes from Urmia, Iran voluntarily participated in the study after completing an informed consent form in 2010. Venous blood samples were collected in three stages: prior to, immediately and 3 h after an incremental exercise (12 km/h at a 5% gradient for 20 min). Real-time PCR was used to assess superoxide dismutase1 (SOD-1) gene expression as was an autoanalyzer for hydrogen peroxide (H2O2) and LDH concentrations.Results: LDH concentration significantly increased in both stages of the exercise (immediately and 3 h after the exercise), (respectively, P=0.009 and P=0.026), but H2O2 concentration significantly increased only in the recovery phase (P=0.002). SOD-1 mRNA did not significantly increase in any stage of the exercise (P=0.05). Moreover, there was only a significant correlation between SOD-1 mRNA and H2O2 increase (P=0.014).Conclusion: Incremental exercise increased H2O2 and LDH levels in female athletes but only free radicals had a significant effect on SOD-1 gene expression.