The resolution of lactate dehydrogenase isozymes in tissue samples obtained from various regions of the rabbit brain was carried out by cellulose acetate electrophoresis. 1) Most regions of the brain showed an H-type isozyme pattern. 2) Five clear1y differentiated patterns of isozyme activity were found throughout the entire cerebral cortex with no difference between the lobes of the cerebral cortex. 3) All 5 patterns were found in the upper brain, while 4 patterns-LDH-1, 2, 3 and very 1ow activity of LDH-4 were found in the lower brain.
Animal ; Brain/enzymology* ; Isoenzymes ; Lactate Dehydrogenase/analysis* ; Rabbits ; Tissue Distribution

OBJECTIVETo explore the pathophysiological and biomechanical features of skeletal muscular injury for providing a rational basis for its treatment, prevention and rehabilitation.

METHODSIn 70 adult rabbits, the left tibialis anterior (TA) muscle was stretched to injury, while the right TA muscle served as control. Histological, enzymohistochemical and biomechanical changes were observed on days 0, 1, 2, 3, and 7 after injury. Cytochrome oxidase (CCO), acid phosphatase (ACP), ATPase, succinate dehydrogenase (SDH), malate dehydrogenase (MDH), NADH-diaphorase (NADHD), glutamatedehydrogenase (GDH), alpha-glycerophosphate dehydrogenase (alpha-GPD) and lactate dehydrogenase (LDH) were measured. The examined biomechanical parameters included maximal contractile force, ultimate load, length, energy absorption, tangent stiffness, and rupture site.

RESULTSPartial or complete rupture of TA muscle occurred near the muscle-tendon junction. There was an intense inflammatory reaction on day 1 and 2 after injury. Endomysium fibrosis and myotube formation were observed on day 3, and developed further on day 7. The activity of cell oxidases (CCO, ATPase, MDH, alpha-GPD, SDH, NADHD and GDH) showed a significant drop from day 0 to 2, and resumed with different levels on day 3. The increment of enzymatic activities continued on day 7 and the levels of NADHD and alpha-GPD reached to the levels of control muscle. Maximal contractile force was 70.17%+/-3.82% of controls immediately after injury, 54.82%+/-3.09% at 1 day, 66.41%+/-4.36% at 2 days, 78.39%+/-4.90% at 3 days and 93.64%+/-5.02% at 7 days. Ultimate load was 85.78%+/-7.54% of controls at the moment of injury, 61.44%+/-5.91% at 1 day, 49.17%+/-4.26% at 2 days, 64.43%+/-5.02% at 3 days, and 76.71%+/-6.46% at 7 days.

CONCLUSIONSEndomysium fibrosis and scar formation at the injured site are responsible for frequent recurrence of skeletal muscle injury. Recovery of tensile load slower than that of maximal contractile force may be another cause. Whether the injured muscle returns to normal exercise is mainly determined by the tensility on which the muscle-tendon can bear rather than the maximal contractile force.

Acid Phosphatase ; analysis ; Adenosine Triphosphatases ; analysis ; Animals ; Biomechanical Phenomena ; Dihydrolipoamide Dehydrogenase ; analysis ; Electron Transport Complex IV ; analysis ; Glutamate Dehydrogenase ; analysis ; Glycerolphosphate Dehydrogenase ; analysis ; L-Lactate Dehydrogenase ; analysis ; Malate Dehydrogenase ; analysis ; Muscle, Skeletal ; injuries ; pathology ; physiology ; Rabbits ; Succinate Dehydrogenase ; analysis

AIMTo explore the adapting metabolic mechanisms of the plateau zokors to the hypoxic-hypercapnic environment.

METHODSThe activities of lactate dehydrogenase in serum and tissues, and the content of lactate in serum of plateau zokors in spring, summer and autumn were determined by using method of enzyme analysis. The spectrums of lactate dehydrogenase isoenzymes in serum and tissues of plateau zokors in spring, summer and autumn were analyzed by using method of the discontinuous systemic poly-acrylamide perpendicular plank gel electrophoresis.

RESULTSThe activities of lactate dehydrogenase in serum had obvious seasonally difference that were higher in spring and lower in autumn, and the content of lactate in serum showed same changing pattern. The spectrums of lactate dehydrogenase isoenzymes in serum showed five bands that were LDH1, LDH2, LDH3, LDH4 and LDH5 from positive pole to negative pole respectively, it showed clearly two bands in serum of summer that were LDH4 and LDH5 and one band in serum of autumn that was LDH5. The activities of LDH in tissues of skeleton muscle, cardiac muscle and brain were higher compared with the other tissues, it decreased markedly from spring to summer to autumn. In tissues of liver, kidney and lungs, activities of LDH were lower. Activities of LDH in livers, were significantly higher in spring compared that in summer and autumn, which had no obvious difference between summer and autumn. Activities of LDH in kidneys and lungs, showed no obviously difference between spring and summer, which decreased markedly in autumn. The spectrums of lactate dehydrogenase isoenzymes in tissues of cardiac muscle, liver, lungs, kidney, brain and skeleton muscle showed five bands, the spectrums were obvious different in different tissues, and the content of LDH isoenzymes showed seasonal changes in different tissues.

CONCLUSIONGlycolysis levels in plateau zokors had obvious seasonally change which increased in spring and decreased in autumn significantly. It related to the activity of plateau zokors in different seasons and seasonal fluctuation of oxygen and carbon dioxide in burrows of plateau zokors.

Animals ; Carbon Dioxide ; metabolism ; Isoenzymes ; analysis ; metabolism ; L-Lactate Dehydrogenase ; analysis ; metabolism ; Rodentia ; metabolism ; Seasons

Hemolysis frequently causes preanalytical errors in laboratory measurements. We aimed to develop a quality improvement indicator for evaluating the extent of inappropriate procedures causing hemolysis in clinical samples collected in medical care units. We defined the threshold value of the hemolysis index (H index) causing significant interference with analyte measurement and analyzed the H index values of clinical samples in relation to the threshold. The H index threshold value causing a 10% bias in the measurement of lactate dehydrogenase was found to be 25. The monthly mean H index and monthly frequency of samples with an H index >25 were significantly different among the types of ward (P=0.001, respectively), and significantly decreased after replacement of a laboratory centrifuge lacking temperature control (20.6±0.58 vs 23.30±1.08, P=0.01; 23.4±1.69% vs 32.6±1.78%, P=0.01). The monthly mean H index and the monthly frequency of samples with an H index above a threshold value may be useful quality improvement indicators for detection of inappropriate procedures in the acquisition and handling of blood samples in medical care units.
Hemoglobins/analysis ; Hemolysis ; Humans ; L-Lactate Dehydrogenase/analysis ; Laboratories, Hospital/*standards ; Quality Improvement/*standards ; Specimen Handling

AIMTo establish a model of ischemia/reperfusion injury on L-6TG cell.

METHODSCultured L-6TG cells were divided into 2 groups: control group (C), ischemia/reperfusion group (I/R), LDH in culture fluid, SOD, XOD, free calcium in L-6TG cell and mitochondria respiration were evaluated in each group, the micromorphologic changes were observed with microscope.

RESULTSCompared with control group, after L-6TG cell suffered ischemia 4 hours and reperfusion 4 hours, LDH in culture fluid, XOD, free calcium in L-6TG cell all increased significantly, while SOD in L-6TG cell and mitochondrial respiration decreased, structural damage to L-6TG cell was severe.

CONCLUSIONUsing mimicking ischemic solution and mimicking reperfusion solution can successfully establish a model of ischemia/reperfusion injury on L-6TG cell.

Animals ; Cells, Cultured ; Colorimetry ; L-Lactate Dehydrogenase ; analysis ; Muscle, Skeletal ; blood supply ; Rats ; Reperfusion Injury

BACKGROUND AND OBJECTIVES: Nasal natural killer T (NK/T) cell lymphomas are relatively common in Asia, but the prognostic factors are not well known. The purpose of this research was therefore to evaluate those prognostic factors. SUBJECTS AND METHOD: We reviewed and analyzed the medical records of 68 patients diagnosed as nasal NK/T cell lymphomas between 1984 and 2003 at Ajou University Hospital and at Yonsei University Hospital. Prognostic factors that include age, B symptoms, serum lactate dehydrogenase (LDH) levels, Eastern cooperative oncology group (ECOG) performance status, international prognostic indices (IPI), treatment modality, and Ann Arbor tumor stages were analyzed using the methods of univariate and multivariate statistics. RESULTS: The five-year overall survival rate was 43%. By univariate analysis, we found ECOG performance status, Ann Arbor tumor stages, B symptoms, and IPI to be significant prognostic factors of nasal NK/T cell lymphoma. The multivariate analysis showed that ECOG performance status and B symptoms were significant. CONCLUSION: ECOG performance status, Ann Arbor tumor stages, B symptoms, and IPI could all be prognostic factors of the nasal NK/T cell lymphoma. Among these factors, ECOG performance status and B symptoms may be regarded more useful in diagnosis of the disease than others.
Asia ; Diagnosis ; Humans ; L-Lactate Dehydrogenase ; Lymphoma* ; Medical Records ; Multivariate Analysis ; Survival Rate

Albumin is the most abundant protein in human serum. A dye-binding method is commonly used in clinical laboratories for its estimation using different types of dyes. However, all these dye methods were interfered by a variety of compounds. Here we present a method for the detection of albumin in human serum and other biological fluids. The principle is based on the fact that lactate dehydrogenase isoenzyme-5 (LDH-5) binds specifically to Dextran-Blue (DB). Albumin inhibits the binding of LDH-5 with DB. Absence of LDH activity in DB fraction after gel filtration indicates the presence of albumin in sample and vice versa.
Chemistry, Clinical/*methods ; Chromatography, Gel ; Human ; Isoenzymes/metabolism ; Lactate Dehydrogenase/metabolism ; Protein Binding ; Sepharose/chemistry ; Serum Albumin/*analysis

PURPOSE: The extranodal natural killer (NK)/T-cell lymphoma (NKTCL) of non-upper aerodigestive tract (NUAT) was found to have clinical heterogeneity compared with NKTCL of the upper aerodigestive tract (UAT) in small scale studies. We conducted this study in a much larger cohort to analyze the clinical characteristics, prognostic factors, treatment modality, and clinical outcomes of patients with NUAT-NKTCL. MATERIALS AND METHODS: From January 2001 to December 2017, a total of 757 NKTCL patients were identified and included in this study, including 92 NUAT-NKTCL patients (12.2%) and 665 UAT-NKTCLpatients (87.8%). RESULTS: NUAT-NKTCL patients had relatively poorer performance status, more unfavorable prognostic factors, and more advanced stage, compared with UAT-NKTCL patients. The 5-year overall survival (OS) was 34.7% for NUAT-NKTCL, which was significantly worse than UAT-NKTCL (64.2%, p<0.001). The median OS duration was 30.9 months for NUAT-NKTCL. Multivariate analysis showed that presence with B symptoms and elevated serum lactate dehydrogenase independently predicted worse OS. International prognostic index score and prognostic index of natural killer lymphoma score still had prognostic values in NUAT-NKTCL, while the Ann Arbor system could not accurately predict the OS. CONCLUSION: NUAT-NKTCL is a distinctive subtype of NKTCL in many aspects. Patients with NUAT-NKTCL have relatively poorer performance status, more unfavorable prognostic factors, more advanced stage, and poorer prognosis.
Cohort Studies ; Humans ; L-Lactate Dehydrogenase ; Lymphoma ; Lymphoma, Extranodal NK-T-Cell ; Multivariate Analysis ; Population Characteristics ; Prognosis

OBJECTIVETo compare the concentrations of IgA, lactate dehydrogenase, lysozyme and alkaline phosphatase (ALP) in unstimulated (UWS) and stimulated (SWS) whole saliva between children with severe early childhood caries (S-ECC) and children without caries.

METHODSOne hundred and ninety-two children aged from 42 to 54 months were recruited from 11 urban kindergartens in Beijing. The S-ECC group contained 98 children with more than 5 decayed teeth, and the control group contained 94 caries-free children. The age and sex were matched in the two groups. Two milliliter UWS and 2 ml SWS was collected between 9 and 11 a.m. The salivary IgA was measured by immunoturbidimetric technique. The concentrations of lactate dehydrogenase and ALP were measured by continuous monitoring method, while lysozyme was detected by turbidimetric technique. All results for paired observations between unstimulated and stimulated whole saliva were analysed by paired-samples t test.

RESULTSIn both UWS and SWS, the concentrations of IgA, lactate dehydrogenase and lysozyme in S-ECC children were higher than those in caries-free children (P < 0.01), but the concentration of ALP showed no significant difference in SWS between S-ECC children and caries-free children (P > 0.05).

CONCLUSIONSThe presence of early childhood caries may be associated with an increase of IgA, lactate dehydrogenase and lysozyme in unstimulated and stimulated whole saliva.

Alkaline Phosphatase ; analysis ; Child, Preschool ; Dental Caries ; metabolism ; Female ; Humans ; Immunoglobulin A ; analysis ; L-Lactate Dehydrogenase ; analysis ; Male ; Muramidase ; analysis ; Saliva ; enzymology ; immunology

OBJECTIVETo examine the protective effect of ecdysterone (ECR) against beta-amyloid peptide fragment(25-35) (Abeta(25-35))-induced PC12 cells cytotoxicity, and to further explore its mechanism.

METHODSExperimental PC12 cells were divided into the Abeta group (treated by Abeta(25-35) 100 micromol/L), the blank group (untreated), the positive control group (treated by Vit E 100 micromol/L after induction) and the ECR treated groups (treated by ECR with different concentrations of 1, 50 and 100 micromol/L). The damaged and survival condition of PC12 cells in various groups was monitored by lactate dehydrogenase (LDH) release and MTT assay. The content of malondialdehyde (MDA) was measured by fluorometric assay to indicate the lipid peroxidation. And the antioxidant enzymes activities in PC12 cells, including superoxide dismutases (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), were detected respectively.

RESULTSAfter PC12 cells were treated with Abeta(25-35) (100 micromol/L) for 24 hrs, they revealed a great decrease in MTT absorbance and activity of antioxidant enzymes, including SOD, CAT and GSH-Px as well as a significant increase of LDH activity and MDA content in PC12 cells (P < 0.01). When the cells was pretreated with 1-100 micromol/L ECR for 24 hrs before Abeta(25-35) treatment, the above-mentioned cytotoxic effect of Abeta(25-35) could be significantly attenuated dose-dependently, for ECR 50 micromol/L, P < 0.05 and for ECR 100 micromol/L, P < 0.01. Moreover, ECR also showed significant inhibition on the Abeta(25-35) induced decrease of SOD and GSH-Px activity, but not on that of CAT.

CONCLUSIONECR could protect PC12 cells from cytotoxicity of Abeta(25-35), and the protective mechanism might be related to the increase of SOD and GSH-Px activities and the decrease of MDA resulting from the ECR-pretreatment.

Amyloid beta-Peptides ; toxicity ; Animals ; Catalase ; analysis ; Ecdysterone ; pharmacology ; Glutathione Peroxidase ; analysis ; L-Lactate Dehydrogenase ; analysis ; Malondialdehyde ; analysis ; PC12 Cells ; Peptide Fragments ; toxicity ; Rats