BACKGROUND In malignant tumors,inflammation plays a vital role in the development,invasion,and metastasis of cancer cells.Diffuse large B-cell lymphoma(DLBCL),the most common malignant proliferative disease of the lym...BACKGROUND In malignant tumors,inflammation plays a vital role in the development,invasion,and metastasis of cancer cells.Diffuse large B-cell lymphoma(DLBCL),the most common malignant proliferative disease of the lymphatic system,is commonly associated with inflammation.The international prognostic index(IPI),which includes age,lactate dehydrogenase(LDH),number of extranodal lesions,Ann Arbor score,and Eastern Cooperative Oncology Group(ECOG)score,can evaluate the prognosis of DLBCL.However,its use in accurately identifying highrisk patients and guiding treatment is poor.Therefore,it is important to find novel immune markers in predicting the prognosis of DLBCL patients.AIM To determine the association between the systemic immune inflammation index(SII),ratio of lymphocytes to monocytes(LMR),ratio of LMR to LDH(LMR/LDH),and prognosis of patients with DLBCL.METHODS A total of 68 patients diagnosed with DLBCL,treated in our hospital between January 2016 and January 2020,were included.χ2 test,Pearson’s R correlation,Kaplan Meier curves,and Cox proportional risk regression analysis were used.The differences in the SII,LMR,and LMR/LDH among patients with different clinicopathological features were analyzed.The differences in progression-free survival time among patients with different SII,LMR,and LMR/LDH expressions and influencing factors affecting the prognosis of DLBCL patients,were also analyzed.RESULTS The LMR and LMR/LDH in patients with Ann Arbor stage III–IV,ECOG score≥2,and SII,IPI score 2–5 were significantly higher than those of patients with Ann Arbor stage I-II and ECOG score<2(P<0.05).Patients with high SII,LMR,and LMR/LDH had progression-free survival times of 34 mo(95%CI:32.52–38.50),35 mo(95%CI:33.42–36.58)and 35 mo(95%CI:33.49–36.51),respectively,which were significantly lower than those with low SII,LMR,and LMR/LDH(P<0.05);the SII,LMR,and LMR/LDH were positively correlated(P<0.05).Cox proportional risk regression analysis showed that the SII,LMR,and LMR/LDH were influencing factors for the prognosis of DLBCL patients(hazard ratio=1.143,1.665,and 1.704,respectively;P<0.05).CONCLUSION The SII,LMR,and LMR/LDH are related to the clinicopathological features of DLCBL,and they also influence the prognosis of patients with the disease.展开更多
BACKGROUND Coronavirus disease 2019(COVID-19)caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)outbreak in China,constitutes a Public Health Emergency of International Concern.It is well known t...BACKGROUND Coronavirus disease 2019(COVID-19)caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)outbreak in China,constitutes a Public Health Emergency of International Concern.It is well known that COVID-19 patients may have increased serum lactate dehydrogenase(LDH)levels in the early stage.The clinical changes in LDH may have predictive value in disease evolution and prognosis in critically ill COVID-19 patients.AIM To examine serum LDH and clinical characteristics in patients with COVID-19 and their predictive value for prognosis.METHODS This retrospective study analyzed the clinical data of forty-seven critical COVID-19 patients in the intensive care unit of the Third People's Hospital of Yichang City from January 27 to March 25,2020 and divided them into survivors and nonsurvivors.The patients were diagnosed according to the World Health Organization interim guidance and critical cases met any one of the following criteria:Respiratory failure and required mechanical ventilation,the occurrence of shock,and the combined failure of other organs that required intensive care unit monitoring and treatments,according to the diagnostic criteria of critical COVID-19.Clinical data including symptoms,detection of SARS-CoV-2,chest computed tomography(CT)images,changes in serum LDH in different clinical phases,and prognosis were collected.Statistical analysis of the data was performed.Continuous variables were expressed as median(interquartile range)and compared with the Mann-Whitney U test.Categorical variables were compared with the Chi-square test.Survival data were analyzed using Kaplan-Meier survival curves and log-rank tests.RESULTS According to chest CT images,we observed the alveolitis and fibrosis stages in all critical patients in this study.Most non-survivors died in the fibrosis stage.Nonsurvivors had fewer days of hospitalization,shorter disease duration,shorter duration of alveolitis and fibrosis,and had dyspnea symptoms at disease onset(P=0.05).Both first and lowest LDH values in the alveolitis stage were more pronounced in non-survivors than in survivors(449.0 U/L vs 288.0 U/L,P=0.0243;445.0 U/L vs 288.0 U/L,P=0.0199,respectively),while the first,lowest and highest values of serum LDH in non-survivors were all significantly increased compared to survivors in the fibrosis phase(449.0 U/L vs 225.5 U/L,P=0.0028;432.0 U/L vs 191.0 U/L,P=0.0007;1303.0 U/L vs 263.5 U/L,P=0.0001,respectively).The cut-off points of first LDH values in the alveolitis and fibrosis phase for distinction of non-survivors from survivors were 397.0 U/L and 263.0 U/L,respectively.In the fibrosis stage,non-survivors had more days with high LDH than survivors(7.0 d vs 0.0 d,P=0.0002).Importantly,patients with high LDH had a significantly shorter median survival time than patients with low LDH in the alveolitis phase(22.0 d vs 36.5 d,P=0.0002),while patients with high LDH also had a significantly shorter median survival time than patients with low LDH in the fibrosis phase(27.5 d vs 40.0 d,P=0.0008).The proportion of non-survivors with detectable SARS-CoV-2 until death in the alveolitis stage was significantly increased compared with that in the fibrosis stage(100%vs 35.7%,P=0.0220).CONCLUSION High LDH and dyspnea symptoms were positive predictors of an adverse outcome in critical COVID-19.The rapid progressive fibrosis stage was more perilous than the alveolitis stage,even if SARS-CoV-2 is undetectable.展开更多
Objectives:To determine the predictive value of lactate dehydrogenase(LDH)in the diagnosis of septic shock and its association with other prognostic scores in critical pediatric patients.Methods:A cross-sectional stud...Objectives:To determine the predictive value of lactate dehydrogenase(LDH)in the diagnosis of septic shock and its association with other prognostic scores in critical pediatric patients.Methods:A cross-sectional study was performed at Children’s Hospital of Cairo University between June 2019 and December 2019.A total of 200 pediatric patients were divided into the septic shock group[100 critically ill patients with septic shock from the pediatric intensive care unit(PICU)]and the control group(100 patients with only sepsis).LDH was determined in the first 24 hours of admission.The sensitivity and specificity of LDH in diagnosis of septic shock were assessed;the levels of related indicators of patients with different etiologies were compared;correlations between LDH,Paediatric Index of MortalityⅡ,and Pediatric Sequential Organ Failure Assessment(pSOFA)were analyzed.Results:Median LDH was 512μL(406.50-663.00)in the septic shock group and was significantly higher than that[190μL(160.00-264.50)]in the control group(P<0.001).Besides,median LDH in children with chest infecion was higher than that in children with other diagnoses(P=0.047).A good positive correlation was found between pSOFA and LDH(r=0.503,P<0.001).Conclusions:LDH could be a potential inflammatory marker in the diagnosis of septic shock and is valuable for PICU admission decisions.展开更多
BACKGROUND Coronavirus disease 2019(COVID-19)is amid an ongoing pandemic.It has been shown that patients with cardiovascular comorbidities are at higher risk of severe illness of COVID-19.AIM To find out the relations...BACKGROUND Coronavirus disease 2019(COVID-19)is amid an ongoing pandemic.It has been shown that patients with cardiovascular comorbidities are at higher risk of severe illness of COVID-19.AIM To find out the relationship between cardiovascular comorbidities and severe illness of COVID-19.METHODS The clinical data of 140 COVID-19 patients treated from January 22,2020 to March 3,2020 at our hospital were retrospectively collected.The clinical characteristics were compared between patients with mild illness and those with severe illness.RESULTS There were 75 male patients and 65 female patients(53.6%vs 46.4%).The mean age was 45.4±14.6 years(range,2-85 years).Most of the patients had mild illness(n=114,81.4%)and 26 patients had severe illness(18.6%).The most common symptom was fever(n=110,78.6%),followed by cough(n=82,58.6%)and expectoration(n=51,36.4%).Eight patients were asymptomatic but were positive for severe acute respiratory syndrome coronavirus 2 RNA.Patients with severe illness were significantly more likely to be hypertensive than those with mild illness[(10/26,38.4%)vs(22/114,19.3%),P=0.036].The levels of lactate dehydrogenase were significantly higher in the severe illness group than in the mild illness group(299.35±68.82 vs 202.94±63.87,P<0.001).No patient died in either the severe illness or the mild illness group.CONCLUSION Hypertension and elevated levels of lactate dehydrogenase may be associated with severe illness of COVID-19.展开更多
AIM:To investigate the changes in levels of the lactate dehydrogenase(LDH)enzyme in corneal edema after cataract surgery with trans-corneal oxygenation therapy.METHODS:This pre-post design study design conducted on 15...AIM:To investigate the changes in levels of the lactate dehydrogenase(LDH)enzyme in corneal edema after cataract surgery with trans-corneal oxygenation therapy.METHODS:This pre-post design study design conducted on 15 patients with corneal edema after cataract surgery and receiving trans-corneal oxygenation therapy.Tear sample(using Schirmer paper,from the inferior fornix of the conjunctiva)was carried out prior to trans-corneal oxygenation therapy,on the day 2(D2)and day 5(D5)postoperatively before and after trans-corneal oxygenation therapy.Visual acuity[VA(Log MAR)],corneal endothelial density,central corneal thickness(CCT),and coefficient of variation corneal endothelial(Co V)were recorded.The value of LDH was measured using ELISA.The difference in mean LDH value before and after trans-corneal oxygenation therapy,between two groups were analyzed using Wilcoxon signed rank test.RESULTS:There was a decrease in LDH tear concentration at D2(pre vs post:1127.54±497.09 vs 696.91±489.49;P=0.002)and D5(pre vs post:1064.17±677.77 vs 780.28±428.95;P=0.027)after trans-corneal oxygenation therapy as well as decrease in LDH concentration on the D2 compared to D5(P=0.041).The mean CCT was decreased significantly after the administration of trans-corneal oxygenation(pre vs post:632.10±25.66 vs 563.90±51.54;P=0.005).The mean VA and Co V increased significantly after the administration of trans-corneal oxygenation(P=0.001 and P=0.028,respectively).However,there was no difference in mean of corneal endothelial density(P=0.814).CONCLUSION:Trans-corneal oxygenation therapy is associated with significant decrease of tears LDH levels in post cataract surgery with corneal edema.It is accompanied by clinical improvement such as significant reduction of CCT.展开更多
Objective:To identify full length cDNA sequence of lactate dehydrogenase(LDH) from adult Echinococcus granulosus(E.granulosus) and to predict the structure and function of its encoding protein using bioinformatics met...Objective:To identify full length cDNA sequence of lactate dehydrogenase(LDH) from adult Echinococcus granulosus(E.granulosus) and to predict the structure and function of its encoding protein using bioinformatics methods.Methods:With the help of NCBI,EMBI, Expasy and other online sites,the open reading frame(ORF),conserved domain,physical and chemical parameters,signal peptide,epitope,topological structures of the protein sequences were predicted and a homology tertiary structure model was created:Vector NT1 software was used for sequence alignment,phylogenetic tree construction and tertiary structure prediction. Results:The target sequence was 1 233 bp length with a 996 bp biggest ORF encoding 331 amino acids protein with typical L-LDH conserved domain.It was confirmed as full length cDNA of LDH from E.granulosus and named as EgLDH(GenBank accession number:HM748917).The predicted molecular weight and isoelectric point of the deduced protein were 3 5516.2Da and 6.32 respectively.Compared with LDHs from Taenia solium,Taenia saginata asiatica,Spirometra erinaceieuropaei.Schistosoma japonicum,Clonorchis sinensis and human,it showed similarity of 86% ,85% ,55% ,58% ,58% and 53% ,respectively.EgLDH contained 3 putative transmembrane regions and 4 major epitopes(54aa-59aa.81aa-87aa,97aa-102aa,307aa-313aa),the latter were significant different from the corresponding regions of human LDH.In addition,some NAD and substrate binding sites located on epitopes 54aa-59aa and 97aa-102aa,respectively.Tertiary structure prediction showed that 3 key catalytic residues 105R,165D and 192H forming a catalytic center near the epitope 97aa-102aa,most NAD and substrate binding sites located around the center.Conclusions:The full length cDNA sequences of EgLDH were identified.It encoded a putative transmembrane protein which might be an ideal target molecule for vaccine and drugs.展开更多
Objective The aim of the study was to investigate the role of serum lactate dehydrogenase(LDH) levels in evaluating the efficacy of transcatheter arterial chemoembolization(TACE) for primary liver cancer.Methods A tot...Objective The aim of the study was to investigate the role of serum lactate dehydrogenase(LDH) levels in evaluating the efficacy of transcatheter arterial chemoembolization(TACE) for primary liver cancer.Methods A total of 52 patients with liver cancer admitted in our hospital(Huangzhou District People's Hospital, Huanggang, China) from June 2015 to December 2017 were selected and divided into control group(LDH of ≤ 450 U/L, n = 26) and observation group(LDH of > 450 U/L, n = 26), based on the pretreatment level of LDH. Based on the changes in serum LDH levels before and after treatment, patients were classified into two groups: LDH increased group(22 cases) and LDH decreased group(30 cases). The relationship between LDH levels and efficacy of TACE treatment was analyzed in the four groups retrospectively. Results No significant difference was seen in the clinical characteristics(gender, median age, performance status Eastern Cooperative Oncology Group, and staging system) between the control and observation groups. The efficacy rate in the control group was 57.7%, whereas that in the observation group was 42.3%(P > 0.05). The 1-year survival rate in the observation group was 53.8% and that in the control group was 84.6%(P < 0.05).Conclusion Serum LDH levels may be of clinical value in evaluating the efficacy of TACE in patients with hepatocellular carcinoma.展开更多
A sublethal concentration of technical grade endosulfan （END） inhibited 35 to 55% of the activities of cytoplasmic malate dehydrogenase （cMDH）, mitochondrial malate dehydrogenase （mMDH）, and lactate dehydrogena...A sublethal concentration of technical grade endosulfan （END） inhibited 35 to 55% of the activities of cytoplasmic malate dehydrogenase （cMDH）, mitochondrial malate dehydrogenase （mMDH）, and lactate dehydrogenase （LDH） in the liver and the skeletal muscle of a freshwater catfish, Clarias halrachus, after 7 days of exposure. The activity remained in the inhibited state up to 28 days. The withdrawal of END from the medium after 1 week of exposure gradually restored the activities to control levels within 21 days in the skeletal muscle and 28 days in the liver. The administration of actinomycin D or cycloheximide between the 14th and the 21st day of the withdrawal of END almost completely inhibited the withdrawal-dependent recovery in the activities of all the three enzymes. This indicates de novo synthesis of the enzymes during the recovery period. A conjoint treatment of END and triiodothyronine （T<sub>3</sub>） raised the activities of cMDH, mMDH, and LDH in the liver and the skeletal muscle up to the control levels. This shows that the inhibitory effect of END may be relieved in presence of T<sub>3</sub>. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed few changes in the pattern of cytoplasmic proteins of the liver and the skeletal muscle in response to exposure to END. 1990 Academic Press. Inc.展开更多
Aim: To evaluate the effect of oxidative stress on the spermatogenesis and lactate dehydrogenase-X (LDH-X) activity in mouse testis. Methods: For creating different levels of oxidative stress in mice, three selenium (...Aim: To evaluate the effect of oxidative stress on the spermatogenesis and lactate dehydrogenase-X (LDH-X) activity in mouse testis. Methods: For creating different levels of oxidative stress in mice, three selenium (Se) level diets were fed in separate groups for 8 weeks. Group 1 animals were fed yeast-based Se-deficient (0.02 ppm) diet. Group 2 and Group 3 animals were fed with the same diet supplemented with 0.2 ppm and 1 ppm Se as sodium selenite, respectively. After 8 weeks, biochemical and histopathological observations of the testis were carried out. LDH-X levels in the testis were analyzed by western immunoblot and ELISA. Results: A significant decrease in testis Se level was observed in Group 1 animals, whereas it was enhanced in Group 3 as compared to Group 2. The glutathione peroxidase (GSH-Px) activity was significantly reduced in both the liver and testis in Group 1, but not in Group 2 and 3. A significant increase in the testis glutathione-S-transferase (GST) activity was observed in Group 1,whereas no significant change was seen in Groups 2 and 3. Histological analysis of testis revealed a normal structure in Group 2. A significant decrease in the germ cell population in Group 1 was observed as compared to Group 2 with the spermatids and mature sperm affected the most. Decrease in the lumen size was also observed. In the Se-excess group (Group 3), displacement of germ cell population was observed. Further, a decrease in the LDH-X level in testis was observed in Group 1. Conclusion: Excessive oxidative stress in the Se deficient group, as indicated by changes in the GSH-Px/GST activity, affects the spermatogenic process with a reduction in mature sperm and in turn the LDH-X level. (Asian J Androl 2004 Sep; 6: 227-232)展开更多
Objective:To explore antischitosome effects of artemether,hemin and Fe on S/LDH.Methods: Enzyme activity of rS/LDH was assayed in the standard reaction system by adding different concentration of reagents(0.00-0.10 mM...Objective:To explore antischitosome effects of artemether,hemin and Fe on S/LDH.Methods: Enzyme activity of rS/LDH was assayed in the standard reaction system by adding different concentration of reagents(0.00-0.10 mM artemether,0.00-0.02 mM hemin,0.00-0.50 mM Fe<sup>3+</sup>). Same solvents of the each reagent were used as control.Results:There was no enzyme activity inhibition observed at 0.10 mM artemther:obivious inhibition for lactate oxidation reaction and pyruvate reduction reaction were detected at 0.002 mM and 0.004 mM of hemin,respectively: comparing with that of the control（P【0.05）.The relative enzymatic activity inhibitions for pyruvate reduction reaction and lactate oxidation reaction at 0.02 mM hemin were 93.48%and 100.00%,respectively,comparing with that of the control（P【0.01）:both pyruvate reduction and lactate oxidation reaction were inhibited completely at 0.50 mM Fe<sup>3+</sup>,comparing with that of the control（P【0.01）.Conclusions:The results implied that SjLDH was not the direct molecular target of artemether.Hemin and Fe are inhibitors of SjLDH.展开更多
Purose:To determine levels of malate dehydrogenase(MDH),lactate dehydroge-nase(LDH)and their isoenzymes in tears of normal Chinese subjects and patients with ocular surface disorders.Methods:The age range of normal su...Purose:To determine levels of malate dehydrogenase(MDH),lactate dehydroge-nase(LDH)and their isoenzymes in tears of normal Chinese subjects and patients with ocular surface disorders.Methods:The age range of normal subjects was10-88,with136mal and 128fe-male subjects.123patients suffered from ocular surface disorders.Tears were col-lected from lower fornix on Xinghua filter disc(0.1mm thick,5mm in diameter).The values of tearMDHand LDHwere determined by MONARCH-2000Ana-lyzer(U.S.A)Their isoenzymes were separated by acetate cellulose elec-trophoresis and were determined by Model CDS-200light densitometer.Results:The normal values of tear LDH and MDH were 45.51+23.00-81.35+37.84umol·s^-1/Land11.00+5.33-19.50+9.17umol·s^-1/Lrespectively,dis-regarding sex or eye distriction(P>0.05).The values of tear LDHandMDH in the group aged10-19were significantly lower than in another groups(P<0.05),95%normal ranges of tearMDHaged below19and above20were3.63-19.90umol·s^-1/L.THe MDH isoenzymes comprised MDHs and MDHm,the former accounting for80.0-89.1%.The LDH isoenzymes comprised 5varieties.of which the ratioH/Mof subunit H tosubunit Mwas0.196+0.02.Levels of tear LDH,MDHand their isoenzymes in different diseases were various.Conclusions;Tear LDH/MDHratio reflected sensitively the matabolism of corneae and conjunetival epithelium.The changes in LDH isoenzymes were hel-ful to the differential diagnosis of external eye diseases,and the increase of MDHm reflected sensitively the degree of injury to the corneal epithelium.展开更多
Poikilothermic animals living in high-altitude environments can be greatly affected by the anaerobic metabolism and lactate recycling, which are catalyzed by an enzyme called lactate dehydrogenase(LDH). However, the f...Poikilothermic animals living in high-altitude environments can be greatly affected by the anaerobic metabolism and lactate recycling, which are catalyzed by an enzyme called lactate dehydrogenase(LDH). However, the function and possible regulatory mechanisms of their anaerobic glycolysis remained elusive. We compared the difference in LDH between a native high-altitude(4 353 m) lizard, Phrynocephalus erythrurus, and a closely related species, Phrynocephalus przewalskii that lives in intermediate altitude environment(1 400 m). The activity of LDH, the concentration of lactate, the distribution of isoenzyme, and the mRNA amounts of Ldh-A and Ldh-B were determined. In cardiac muscle, the lactate-forming activity of P. erythrurus in LDH was higher than of P. przewalskii LDH at all three temperatures tested(10 °C, 25 °C and 35 °C), while lactate-oxidation activity of LDH was significantly different between the two species only at 25 °C and 35 °C. In skeletal muscle, both lactate-forming and lactate-oxidation rates of P. erythrurus were lower than that of P. przewalskii. There was a higher proportion of H subunit and a significantly higher expression of Ldh-B, with a concomitant decrease of lactate concentration in P. erythrurus. These results indicate that P. erythrurus may have a strong potential for anaerobic metabolism, which is likely adapted to the hypoxic environment at high altitudes. Furthermore, P. erythrurus is capable of oxidizing more lactate than P. przewalskii. The Ldh-A cDNA of the two species consists of a 999 bp open reading frame(ORF), which encodes 332 amino acids, while Ldh-B cDNA consists of a 1 002 bp ORF encoding 333 amino acids. LDHA has the same amino acid sequence between the two species, but three amino acid substitutions(V12 I, N21 S and N318 K) were observed in LDHB. Structure analysis of LDH indicated that the substitutions of residues Val12 and Asp21 in P. erythrurus could be responsible for the highaltitude adaptation. The LDH characteristics of LDH in P. erythrurus suggest unique adaptation strategies of anaerobic metabolism in hypoxia and cold environments at high altitudes for poikilothermic animals.展开更多
Lactate dehydrogenase(LDH),a vital enzyme in anaerobic glycolysis,is closely associated with the survival of parasites.Previous studies of some parasites have shown that LDH exhibits unique physicochemical properties ...Lactate dehydrogenase(LDH),a vital enzyme in anaerobic glycolysis,is closely associated with the survival of parasites.Previous studies of some parasites have shown that LDH exhibits unique physicochemical properties and molecular structures and may be an ideal potential target for diagnosis and drug screening.In this study,we aimed to investigate the effects of acetamizuril,a novel anticoccidial compound,on LDH in the second-generation merozoites of Eimeria tenella(mz-LDH).Quantitative real-time PCR,Western blot,immunofluorescence and enzyme activity assays were each applied to detect the changes of mz-LDH.Our results indicated that the mRNA and protein levels of mz-LDH were reduced upon acetamizuril treatment.Immunolocalization of mz-LDH demonstrated that considerable amount of mz-LDH was distributed around or in the nuclei of second-generation merozoites within the untreated group;in contrast,the acetamizuril-treated group had very low level of mz-LDH.Meanwhile,LDH enzyme activity assay suggested that a decreased LDH enzyme activity in both cytoplasm and nucleus of merozoites in the acetamizuril-treated group.Moreover,the induced apoptosis in second-generation merozoites by the acetamizuril was evaluated by detecting caspase 3 activity,and acetamizuril was found to significantly increase caspase 3 activity.The above findings show that LDH may play an important role in the mediating the activity of acetamizuril against coccidiosis,and further investigation into this aspect might contribute to new light on the pathogenesis of E.tenella during its interaction with acetamizuril.展开更多
In this paper, differential pulse voltammetry (DPV) was applied to study the effects of aluminum Al(Ⅲ) on the lactate dehydrogenase (LDH) activity. Michaelis–Menten constant (KmN ADH) and maximum velocity (vmax) in ...In this paper, differential pulse voltammetry (DPV) was applied to study the effects of aluminum Al(Ⅲ) on the lactate dehydrogenase (LDH) activity. Michaelis–Menten constant (KmN ADH) and maximum velocity (vmax) in the enzyme promoting catalytic reaction of "pyruvate(Pyr) + NADH + H+LDDHlactate + NAD+" under different conditions by monitoring DPV reduction current of NAD+ were reported.展开更多
Objective: To construct a prokaryotic recombinant vector for mouse lactate dehydrogenase-C and to detect its expression in BL21. Methods: The coding sequence of mouse lactate dehydrogenase subunit C was amplified from...Objective: To construct a prokaryotic recombinant vector for mouse lactate dehydrogenase-C and to detect its expression in BL21. Methods: The coding sequence of mouse lactate dehydrogenase subunit C was amplified from mouse testis RNA with specific primers and cloned into pGEX-2T after restriction digestion with BamH I and EcoR I. GST fusion protein was expressed after induction with IPTG. Results: Sequencing and restriction digestion of the recombinant plasmid revealed the coding sequence for mouse lactate dehydrogenase subunit C. A protein band of about 60 000 could be induced by IPTG in the recombinant plasmid. Conclusion: The coding sequence of mouse lactate dehydrogenase subunit C was introduced into the pGEX-2T plasmid and a GST-fused protein could be induced at a high level.展开更多
Objective. To study the characteristics of changes of LDH enzyme patterns of mice under slight hypoxia. Methods. Mice treated with artificial hypoxia, various tissues were made for the test of LDH enzymatic activity b...Objective. To study the characteristics of changes of LDH enzyme patterns of mice under slight hypoxia. Methods. Mice treated with artificial hypoxia, various tissues were made for the test of LDH enzymatic activity by the specific staining technique. LDH(1-5) relative percentage enzymatic activity (RPEA) were measured with CS-910 dual-wavelength thin layer chromatography scanner. Results. The RPEA of LDH isozymes of various tissues after slight hypoxia shifted to the isozymes LDH1 and LDH2, whose principal subunits are H subunits, and be RPEA of LDH1(H4), LDH2(H3M) increased, while RPEA of LDH5(M4) in various tissues decreased prominently except the cardiac muscle, and that of LDH4(HM3) decreased as well. After polyacrylamide gel electrophoresis (PAGE) of the hypoxia treated cardiac muscle specimen was made, activity subbands originated regularly in the isozyme patterns of LDH, with the regularity of LDH1 (0 subband), LDH2 (0-1 subbands), LDH3(0-2 subbands), LDH4(1-3 subbands), LDH5(2-4 subbands). After adding appropriate amount of NAD^+ to the hypoxia treated cardiac muscle specimen, PAGE showed the subbands of four isozymes (LDH2-LDH5) reduced or even totally disappeared in the isozyme patterns. Conclusions. The negative feedback regulation of coenzymization and decoenzymization of LDH isozymes is one of the mouse stress responses to slight hypoxia.展开更多
[Objective] To express lactate dehydrogenase C (LDH-C) gene in prokaryotic system and then purify the recombinant protein. [Method] The LDH-C gene was amplified from black-lipped pika (Ochotona curzoniae) by RT-PCR an...[Objective] To express lactate dehydrogenase C (LDH-C) gene in prokaryotic system and then purify the recombinant protein. [Method] The LDH-C gene was amplified from black-lipped pika (Ochotona curzoniae) by RT-PCR and ligated to the expression vector pET-32a. The E. coli BL21 (DE3) carrying the LDH-C gene was obtained and induced by IPTG (isopropy-beta-D-thiogalactoside). The expression products were analyzed by SDS-PAGE and purified by affinity chromatography. [Result] An approximately 1.0 kbp band appeared in the RT-PCR products as theoretically expected. As evidenced by PCR and double enzyme digestion, an approximately 1.0 kbp fragment appeared, which indicated successful construction of expression vector. As analyzed by SDS-PAGE, a fusion protein with molecular weight slightly larger than 45 kDa was expressed in form of inclusion body. And very pure fusion protein was obtained by nickel ions-charged affinity chromatography. [Conclusion] The LDH-C gene of black-lipped pika has been cloned and expressed in E. coli.展开更多
Purpose: The LDH isoenzyme patterns were evaluated in lens of fetus to study the metabolism in human lenses.Methods: LDH isoenzyme electrophoresis was performed in 15 lenses of human fetus aged from 4～6 months.Result...Purpose: The LDH isoenzyme patterns were evaluated in lens of fetus to study the metabolism in human lenses.Methods: LDH isoenzyme electrophoresis was performed in 15 lenses of human fetus aged from 4～6 months.Results: There are 5 bands of LDH in fetus lens. LDH4 lever is the highest, and LDH1 is the lowest, especially in the cortex of lens. LDH1 is higher in lens of 4 months of age than in that of 5 and 6 months of age.Conclusions: LDH isoenzyme in lens of fetus shows mainly anaerobic metabolism in development, but there is also aerobic metabolism, especially in younger fetus.展开更多
A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chloride...A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chlorides in a drug solution for infusion. Sorbitol, Sodium lactate, and Chloride are all officially recognized in the USP monograph. Assay methods are provided through various techniques, with titrations being ineffective for trace-level quantification. Alternatively, IC, AAS, and ICP-MS, though highly accurate, are costly and often unavailable to most testing facilities. When considering methods, it’s important to prioritize both quality control requirements and user-friendly techniques. A simple HPLC simultaneous method was developed for the quantification of Chlorides, Sorbitol, and Sodium Lactate with a shorter run time. The separation utilized a Shimpack SCR-102(H) ion exclusion analytical column (7.9 mm × 300 mm, 7 μm), with a flow rate of 0.6 mL per min. The column compartment temperature was maintained at 40°C, and the injection volume was set at 10 μL, with detection at 200 nm. All measurements were conducted in a 0.1% solution of phosphoric acid. The analytical curves demonstrated linearity (r > 0.9999) in the concentration range of 0.79 to 3.8 mg per mL for Sodium Lactate (SL), 0.16 to 0.79 mg per mL for Sodium Chloride (SC), and 1.5 to 7.2 mg per mL for Sorbitol. Validation of the developed method followed the guidelines of the International Conference on Harmonization (ICH Q2B) and USP. The method exhibited precision, robustness, accuracy, and selectivity. In accelerated stability testing over 6 months, no significant variations were observed in organoleptic analysis and pH. Consequently, the developed method is deemed suitable for routine quality control analyses, enabling the simultaneous determination of Sodium Lactate, Sodium Chloride, and Sorbitol in pharmaceutical formulations and infusions.展开更多
文摘BACKGROUND In malignant tumors,inflammation plays a vital role in the development,invasion,and metastasis of cancer cells.Diffuse large B-cell lymphoma(DLBCL),the most common malignant proliferative disease of the lymphatic system,is commonly associated with inflammation.The international prognostic index(IPI),which includes age,lactate dehydrogenase(LDH),number of extranodal lesions,Ann Arbor score,and Eastern Cooperative Oncology Group(ECOG)score,can evaluate the prognosis of DLBCL.However,its use in accurately identifying highrisk patients and guiding treatment is poor.Therefore,it is important to find novel immune markers in predicting the prognosis of DLBCL patients.AIM To determine the association between the systemic immune inflammation index(SII),ratio of lymphocytes to monocytes(LMR),ratio of LMR to LDH(LMR/LDH),and prognosis of patients with DLBCL.METHODS A total of 68 patients diagnosed with DLBCL,treated in our hospital between January 2016 and January 2020,were included.χ2 test,Pearson’s R correlation,Kaplan Meier curves,and Cox proportional risk regression analysis were used.The differences in the SII,LMR,and LMR/LDH among patients with different clinicopathological features were analyzed.The differences in progression-free survival time among patients with different SII,LMR,and LMR/LDH expressions and influencing factors affecting the prognosis of DLBCL patients,were also analyzed.RESULTS The LMR and LMR/LDH in patients with Ann Arbor stage III–IV,ECOG score≥2,and SII,IPI score 2–5 were significantly higher than those of patients with Ann Arbor stage I-II and ECOG score<2(P<0.05).Patients with high SII,LMR,and LMR/LDH had progression-free survival times of 34 mo(95%CI:32.52–38.50),35 mo(95%CI:33.42–36.58)and 35 mo(95%CI:33.49–36.51),respectively,which were significantly lower than those with low SII,LMR,and LMR/LDH(P<0.05);the SII,LMR,and LMR/LDH were positively correlated(P<0.05).Cox proportional risk regression analysis showed that the SII,LMR,and LMR/LDH were influencing factors for the prognosis of DLBCL patients(hazard ratio=1.143,1.665,and 1.704,respectively;P<0.05).CONCLUSION The SII,LMR,and LMR/LDH are related to the clinicopathological features of DLCBL,and they also influence the prognosis of patients with the disease.
基金Supported by National Natural Science Foundation of China,No.81800070Development Fund Program of Fujian Provincial Health and Family Planning Commission,China,No.2017-1-43.
文摘BACKGROUND Coronavirus disease 2019(COVID-19)caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)outbreak in China,constitutes a Public Health Emergency of International Concern.It is well known that COVID-19 patients may have increased serum lactate dehydrogenase(LDH)levels in the early stage.The clinical changes in LDH may have predictive value in disease evolution and prognosis in critically ill COVID-19 patients.AIM To examine serum LDH and clinical characteristics in patients with COVID-19 and their predictive value for prognosis.METHODS This retrospective study analyzed the clinical data of forty-seven critical COVID-19 patients in the intensive care unit of the Third People's Hospital of Yichang City from January 27 to March 25,2020 and divided them into survivors and nonsurvivors.The patients were diagnosed according to the World Health Organization interim guidance and critical cases met any one of the following criteria:Respiratory failure and required mechanical ventilation,the occurrence of shock,and the combined failure of other organs that required intensive care unit monitoring and treatments,according to the diagnostic criteria of critical COVID-19.Clinical data including symptoms,detection of SARS-CoV-2,chest computed tomography(CT)images,changes in serum LDH in different clinical phases,and prognosis were collected.Statistical analysis of the data was performed.Continuous variables were expressed as median(interquartile range)and compared with the Mann-Whitney U test.Categorical variables were compared with the Chi-square test.Survival data were analyzed using Kaplan-Meier survival curves and log-rank tests.RESULTS According to chest CT images,we observed the alveolitis and fibrosis stages in all critical patients in this study.Most non-survivors died in the fibrosis stage.Nonsurvivors had fewer days of hospitalization,shorter disease duration,shorter duration of alveolitis and fibrosis,and had dyspnea symptoms at disease onset(P=0.05).Both first and lowest LDH values in the alveolitis stage were more pronounced in non-survivors than in survivors(449.0 U/L vs 288.0 U/L,P=0.0243;445.0 U/L vs 288.0 U/L,P=0.0199,respectively),while the first,lowest and highest values of serum LDH in non-survivors were all significantly increased compared to survivors in the fibrosis phase(449.0 U/L vs 225.5 U/L,P=0.0028;432.0 U/L vs 191.0 U/L,P=0.0007;1303.0 U/L vs 263.5 U/L,P=0.0001,respectively).The cut-off points of first LDH values in the alveolitis and fibrosis phase for distinction of non-survivors from survivors were 397.0 U/L and 263.0 U/L,respectively.In the fibrosis stage,non-survivors had more days with high LDH than survivors(7.0 d vs 0.0 d,P=0.0002).Importantly,patients with high LDH had a significantly shorter median survival time than patients with low LDH in the alveolitis phase(22.0 d vs 36.5 d,P=0.0002),while patients with high LDH also had a significantly shorter median survival time than patients with low LDH in the fibrosis phase(27.5 d vs 40.0 d,P=0.0008).The proportion of non-survivors with detectable SARS-CoV-2 until death in the alveolitis stage was significantly increased compared with that in the fibrosis stage(100%vs 35.7%,P=0.0220).CONCLUSION High LDH and dyspnea symptoms were positive predictors of an adverse outcome in critical COVID-19.The rapid progressive fibrosis stage was more perilous than the alveolitis stage,even if SARS-CoV-2 is undetectable.
文摘Objectives:To determine the predictive value of lactate dehydrogenase(LDH)in the diagnosis of septic shock and its association with other prognostic scores in critical pediatric patients.Methods:A cross-sectional study was performed at Children’s Hospital of Cairo University between June 2019 and December 2019.A total of 200 pediatric patients were divided into the septic shock group[100 critically ill patients with septic shock from the pediatric intensive care unit(PICU)]and the control group(100 patients with only sepsis).LDH was determined in the first 24 hours of admission.The sensitivity and specificity of LDH in diagnosis of septic shock were assessed;the levels of related indicators of patients with different etiologies were compared;correlations between LDH,Paediatric Index of MortalityⅡ,and Pediatric Sequential Organ Failure Assessment(pSOFA)were analyzed.Results:Median LDH was 512μL(406.50-663.00)in the septic shock group and was significantly higher than that[190μL(160.00-264.50)]in the control group(P<0.001).Besides,median LDH in children with chest infecion was higher than that in children with other diagnoses(P=0.047).A good positive correlation was found between pSOFA and LDH(r=0.503,P<0.001).Conclusions:LDH could be a potential inflammatory marker in the diagnosis of septic shock and is valuable for PICU admission decisions.
基金the Wenzhou Major Technology Innovation Project,No.ZY202004.
文摘BACKGROUND Coronavirus disease 2019(COVID-19)is amid an ongoing pandemic.It has been shown that patients with cardiovascular comorbidities are at higher risk of severe illness of COVID-19.AIM To find out the relationship between cardiovascular comorbidities and severe illness of COVID-19.METHODS The clinical data of 140 COVID-19 patients treated from January 22,2020 to March 3,2020 at our hospital were retrospectively collected.The clinical characteristics were compared between patients with mild illness and those with severe illness.RESULTS There were 75 male patients and 65 female patients(53.6%vs 46.4%).The mean age was 45.4±14.6 years(range,2-85 years).Most of the patients had mild illness(n=114,81.4%)and 26 patients had severe illness(18.6%).The most common symptom was fever(n=110,78.6%),followed by cough(n=82,58.6%)and expectoration(n=51,36.4%).Eight patients were asymptomatic but were positive for severe acute respiratory syndrome coronavirus 2 RNA.Patients with severe illness were significantly more likely to be hypertensive than those with mild illness[(10/26,38.4%)vs(22/114,19.3%),P=0.036].The levels of lactate dehydrogenase were significantly higher in the severe illness group than in the mild illness group(299.35±68.82 vs 202.94±63.87,P<0.001).No patient died in either the severe illness or the mild illness group.CONCLUSION Hypertension and elevated levels of lactate dehydrogenase may be associated with severe illness of COVID-19.
文摘AIM:To investigate the changes in levels of the lactate dehydrogenase(LDH)enzyme in corneal edema after cataract surgery with trans-corneal oxygenation therapy.METHODS:This pre-post design study design conducted on 15 patients with corneal edema after cataract surgery and receiving trans-corneal oxygenation therapy.Tear sample(using Schirmer paper,from the inferior fornix of the conjunctiva)was carried out prior to trans-corneal oxygenation therapy,on the day 2(D2)and day 5(D5)postoperatively before and after trans-corneal oxygenation therapy.Visual acuity[VA(Log MAR)],corneal endothelial density,central corneal thickness(CCT),and coefficient of variation corneal endothelial(Co V)were recorded.The value of LDH was measured using ELISA.The difference in mean LDH value before and after trans-corneal oxygenation therapy,between two groups were analyzed using Wilcoxon signed rank test.RESULTS:There was a decrease in LDH tear concentration at D2(pre vs post:1127.54±497.09 vs 696.91±489.49;P=0.002)and D5(pre vs post:1064.17±677.77 vs 780.28±428.95;P=0.027)after trans-corneal oxygenation therapy as well as decrease in LDH concentration on the D2 compared to D5(P=0.041).The mean CCT was decreased significantly after the administration of trans-corneal oxygenation(pre vs post:632.10±25.66 vs 563.90±51.54;P=0.005).The mean VA and Co V increased significantly after the administration of trans-corneal oxygenation(P=0.001 and P=0.028,respectively).However,there was no difference in mean of corneal endothelial density(P=0.814).CONCLUSION:Trans-corneal oxygenation therapy is associated with significant decrease of tears LDH levels in post cataract surgery with corneal edema.It is accompanied by clinical improvement such as significant reduction of CCT.
基金Supported by National Nature Science Foundation of China(No:30860070)
文摘Objective:To identify full length cDNA sequence of lactate dehydrogenase(LDH) from adult Echinococcus granulosus(E.granulosus) and to predict the structure and function of its encoding protein using bioinformatics methods.Methods:With the help of NCBI,EMBI, Expasy and other online sites,the open reading frame(ORF),conserved domain,physical and chemical parameters,signal peptide,epitope,topological structures of the protein sequences were predicted and a homology tertiary structure model was created:Vector NT1 software was used for sequence alignment,phylogenetic tree construction and tertiary structure prediction. Results:The target sequence was 1 233 bp length with a 996 bp biggest ORF encoding 331 amino acids protein with typical L-LDH conserved domain.It was confirmed as full length cDNA of LDH from E.granulosus and named as EgLDH(GenBank accession number:HM748917).The predicted molecular weight and isoelectric point of the deduced protein were 3 5516.2Da and 6.32 respectively.Compared with LDHs from Taenia solium,Taenia saginata asiatica,Spirometra erinaceieuropaei.Schistosoma japonicum,Clonorchis sinensis and human,it showed similarity of 86% ,85% ,55% ,58% ,58% and 53% ,respectively.EgLDH contained 3 putative transmembrane regions and 4 major epitopes(54aa-59aa.81aa-87aa,97aa-102aa,307aa-313aa),the latter were significant different from the corresponding regions of human LDH.In addition,some NAD and substrate binding sites located on epitopes 54aa-59aa and 97aa-102aa,respectively.Tertiary structure prediction showed that 3 key catalytic residues 105R,165D and 192H forming a catalytic center near the epitope 97aa-102aa,most NAD and substrate binding sites located around the center.Conclusions:The full length cDNA sequences of EgLDH were identified.It encoded a putative transmembrane protein which might be an ideal target molecule for vaccine and drugs.
文摘Objective The aim of the study was to investigate the role of serum lactate dehydrogenase(LDH) levels in evaluating the efficacy of transcatheter arterial chemoembolization(TACE) for primary liver cancer.Methods A total of 52 patients with liver cancer admitted in our hospital(Huangzhou District People's Hospital, Huanggang, China) from June 2015 to December 2017 were selected and divided into control group(LDH of ≤ 450 U/L, n = 26) and observation group(LDH of > 450 U/L, n = 26), based on the pretreatment level of LDH. Based on the changes in serum LDH levels before and after treatment, patients were classified into two groups: LDH increased group(22 cases) and LDH decreased group(30 cases). The relationship between LDH levels and efficacy of TACE treatment was analyzed in the four groups retrospectively. Results No significant difference was seen in the clinical characteristics(gender, median age, performance status Eastern Cooperative Oncology Group, and staging system) between the control and observation groups. The efficacy rate in the control group was 57.7%, whereas that in the observation group was 42.3%(P > 0.05). The 1-year survival rate in the observation group was 53.8% and that in the control group was 84.6%(P < 0.05).Conclusion Serum LDH levels may be of clinical value in evaluating the efficacy of TACE in patients with hepatocellular carcinoma.
文摘A sublethal concentration of technical grade endosulfan （END） inhibited 35 to 55% of the activities of cytoplasmic malate dehydrogenase （cMDH）, mitochondrial malate dehydrogenase （mMDH）, and lactate dehydrogenase （LDH） in the liver and the skeletal muscle of a freshwater catfish, Clarias halrachus, after 7 days of exposure. The activity remained in the inhibited state up to 28 days. The withdrawal of END from the medium after 1 week of exposure gradually restored the activities to control levels within 21 days in the skeletal muscle and 28 days in the liver. The administration of actinomycin D or cycloheximide between the 14th and the 21st day of the withdrawal of END almost completely inhibited the withdrawal-dependent recovery in the activities of all the three enzymes. This indicates de novo synthesis of the enzymes during the recovery period. A conjoint treatment of END and triiodothyronine （T<sub>3</sub>） raised the activities of cMDH, mMDH, and LDH in the liver and the skeletal muscle up to the control levels. This shows that the inhibitory effect of END may be relieved in presence of T<sub>3</sub>. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed few changes in the pattern of cytoplasmic proteins of the liver and the skeletal muscle in response to exposure to END. 1990 Academic Press. Inc.
文摘Aim: To evaluate the effect of oxidative stress on the spermatogenesis and lactate dehydrogenase-X (LDH-X) activity in mouse testis. Methods: For creating different levels of oxidative stress in mice, three selenium (Se) level diets were fed in separate groups for 8 weeks. Group 1 animals were fed yeast-based Se-deficient (0.02 ppm) diet. Group 2 and Group 3 animals were fed with the same diet supplemented with 0.2 ppm and 1 ppm Se as sodium selenite, respectively. After 8 weeks, biochemical and histopathological observations of the testis were carried out. LDH-X levels in the testis were analyzed by western immunoblot and ELISA. Results: A significant decrease in testis Se level was observed in Group 1 animals, whereas it was enhanced in Group 3 as compared to Group 2. The glutathione peroxidase (GSH-Px) activity was significantly reduced in both the liver and testis in Group 1, but not in Group 2 and 3. A significant increase in the testis glutathione-S-transferase (GST) activity was observed in Group 1,whereas no significant change was seen in Groups 2 and 3. Histological analysis of testis revealed a normal structure in Group 2. A significant decrease in the germ cell population in Group 1 was observed as compared to Group 2 with the spermatids and mature sperm affected the most. Decrease in the lumen size was also observed. In the Se-excess group (Group 3), displacement of germ cell population was observed. Further, a decrease in the LDH-X level in testis was observed in Group 1. Conclusion: Excessive oxidative stress in the Se deficient group, as indicated by changes in the GSH-Px/GST activity, affects the spermatogenic process with a reduction in mature sperm and in turn the LDH-X level. (Asian J Androl 2004 Sep; 6: 227-232)
基金Supported by National Nature Science Fundation of China(No. 30860070)
文摘Objective:To explore antischitosome effects of artemether,hemin and Fe on S/LDH.Methods: Enzyme activity of rS/LDH was assayed in the standard reaction system by adding different concentration of reagents(0.00-0.10 mM artemether,0.00-0.02 mM hemin,0.00-0.50 mM Fe<sup>3+</sup>). Same solvents of the each reagent were used as control.Results:There was no enzyme activity inhibition observed at 0.10 mM artemther:obivious inhibition for lactate oxidation reaction and pyruvate reduction reaction were detected at 0.002 mM and 0.004 mM of hemin,respectively: comparing with that of the control（P【0.05）.The relative enzymatic activity inhibitions for pyruvate reduction reaction and lactate oxidation reaction at 0.02 mM hemin were 93.48%and 100.00%,respectively,comparing with that of the control（P【0.01）:both pyruvate reduction and lactate oxidation reaction were inhibited completely at 0.50 mM Fe<sup>3+</sup>,comparing with that of the control（P【0.01）.Conclusions:The results implied that SjLDH was not the direct molecular target of artemether.Hemin and Fe are inhibitors of SjLDH.
文摘Purose:To determine levels of malate dehydrogenase(MDH),lactate dehydroge-nase(LDH)and their isoenzymes in tears of normal Chinese subjects and patients with ocular surface disorders.Methods:The age range of normal subjects was10-88,with136mal and 128fe-male subjects.123patients suffered from ocular surface disorders.Tears were col-lected from lower fornix on Xinghua filter disc(0.1mm thick,5mm in diameter).The values of tearMDHand LDHwere determined by MONARCH-2000Ana-lyzer(U.S.A)Their isoenzymes were separated by acetate cellulose elec-trophoresis and were determined by Model CDS-200light densitometer.Results:The normal values of tear LDH and MDH were 45.51+23.00-81.35+37.84umol·s^-1/Land11.00+5.33-19.50+9.17umol·s^-1/Lrespectively,dis-regarding sex or eye distriction(P>0.05).The values of tear LDHandMDH in the group aged10-19were significantly lower than in another groups(P<0.05),95%normal ranges of tearMDHaged below19and above20were3.63-19.90umol·s^-1/L.THe MDH isoenzymes comprised MDHs and MDHm,the former accounting for80.0-89.1%.The LDH isoenzymes comprised 5varieties.of which the ratioH/Mof subunit H tosubunit Mwas0.196+0.02.Levels of tear LDH,MDHand their isoenzymes in different diseases were various.Conclusions;Tear LDH/MDHratio reflected sensitively the matabolism of corneae and conjunetival epithelium.The changes in LDH isoenzymes were hel-ful to the differential diagnosis of external eye diseases,and the increase of MDHm reflected sensitively the degree of injury to the corneal epithelium.
基金supported by the National Natural Science Foundation of China (No. 31501860 to Xiaolong TANG, No. 31272313 and No. 31472005 to Qiang CHEN) Fundamental Research Funds for the Central Universities (lzujbky-2017-150 to Xiaolong TANG)Natural Science Foundation of Gansu Province: 1506RJYA243
文摘Poikilothermic animals living in high-altitude environments can be greatly affected by the anaerobic metabolism and lactate recycling, which are catalyzed by an enzyme called lactate dehydrogenase(LDH). However, the function and possible regulatory mechanisms of their anaerobic glycolysis remained elusive. We compared the difference in LDH between a native high-altitude(4 353 m) lizard, Phrynocephalus erythrurus, and a closely related species, Phrynocephalus przewalskii that lives in intermediate altitude environment(1 400 m). The activity of LDH, the concentration of lactate, the distribution of isoenzyme, and the mRNA amounts of Ldh-A and Ldh-B were determined. In cardiac muscle, the lactate-forming activity of P. erythrurus in LDH was higher than of P. przewalskii LDH at all three temperatures tested(10 °C, 25 °C and 35 °C), while lactate-oxidation activity of LDH was significantly different between the two species only at 25 °C and 35 °C. In skeletal muscle, both lactate-forming and lactate-oxidation rates of P. erythrurus were lower than that of P. przewalskii. There was a higher proportion of H subunit and a significantly higher expression of Ldh-B, with a concomitant decrease of lactate concentration in P. erythrurus. These results indicate that P. erythrurus may have a strong potential for anaerobic metabolism, which is likely adapted to the hypoxic environment at high altitudes. Furthermore, P. erythrurus is capable of oxidizing more lactate than P. przewalskii. The Ldh-A cDNA of the two species consists of a 999 bp open reading frame(ORF), which encodes 332 amino acids, while Ldh-B cDNA consists of a 1 002 bp ORF encoding 333 amino acids. LDHA has the same amino acid sequence between the two species, but three amino acid substitutions(V12 I, N21 S and N318 K) were observed in LDHB. Structure analysis of LDH indicated that the substitutions of residues Val12 and Asp21 in P. erythrurus could be responsible for the highaltitude adaptation. The LDH characteristics of LDH in P. erythrurus suggest unique adaptation strategies of anaerobic metabolism in hypoxia and cold environments at high altitudes for poikilothermic animals.
基金supported by the National Natural Science Foundation of China(31101857,31272607 and 31472235)。
文摘Lactate dehydrogenase(LDH),a vital enzyme in anaerobic glycolysis,is closely associated with the survival of parasites.Previous studies of some parasites have shown that LDH exhibits unique physicochemical properties and molecular structures and may be an ideal potential target for diagnosis and drug screening.In this study,we aimed to investigate the effects of acetamizuril,a novel anticoccidial compound,on LDH in the second-generation merozoites of Eimeria tenella(mz-LDH).Quantitative real-time PCR,Western blot,immunofluorescence and enzyme activity assays were each applied to detect the changes of mz-LDH.Our results indicated that the mRNA and protein levels of mz-LDH were reduced upon acetamizuril treatment.Immunolocalization of mz-LDH demonstrated that considerable amount of mz-LDH was distributed around or in the nuclei of second-generation merozoites within the untreated group;in contrast,the acetamizuril-treated group had very low level of mz-LDH.Meanwhile,LDH enzyme activity assay suggested that a decreased LDH enzyme activity in both cytoplasm and nucleus of merozoites in the acetamizuril-treated group.Moreover,the induced apoptosis in second-generation merozoites by the acetamizuril was evaluated by detecting caspase 3 activity,and acetamizuril was found to significantly increase caspase 3 activity.The above findings show that LDH may play an important role in the mediating the activity of acetamizuril against coccidiosis,and further investigation into this aspect might contribute to new light on the pathogenesis of E.tenella during its interaction with acetamizuril.
基金the Natural Science Foundation of Jiangsu Province （BK 2005083） Grant of Analytical Measurements of Nanjing University, The National Science Foundation of China （No. 20575025） Research Funding for the Doctoral Program of Higher Education （No. 20050284030）.
文摘In this paper, differential pulse voltammetry (DPV) was applied to study the effects of aluminum Al(Ⅲ) on the lactate dehydrogenase (LDH) activity. Michaelis–Menten constant (KmN ADH) and maximum velocity (vmax) in the enzyme promoting catalytic reaction of "pyruvate(Pyr) + NADH + H+LDDHlactate + NAD+" under different conditions by monitoring DPV reduction current of NAD+ were reported.
文摘Objective: To construct a prokaryotic recombinant vector for mouse lactate dehydrogenase-C and to detect its expression in BL21. Methods: The coding sequence of mouse lactate dehydrogenase subunit C was amplified from mouse testis RNA with specific primers and cloned into pGEX-2T after restriction digestion with BamH I and EcoR I. GST fusion protein was expressed after induction with IPTG. Results: Sequencing and restriction digestion of the recombinant plasmid revealed the coding sequence for mouse lactate dehydrogenase subunit C. A protein band of about 60 000 could be induced by IPTG in the recombinant plasmid. Conclusion: The coding sequence of mouse lactate dehydrogenase subunit C was introduced into the pGEX-2T plasmid and a GST-fused protein could be induced at a high level.
文摘Objective. To study the characteristics of changes of LDH enzyme patterns of mice under slight hypoxia. Methods. Mice treated with artificial hypoxia, various tissues were made for the test of LDH enzymatic activity by the specific staining technique. LDH(1-5) relative percentage enzymatic activity (RPEA) were measured with CS-910 dual-wavelength thin layer chromatography scanner. Results. The RPEA of LDH isozymes of various tissues after slight hypoxia shifted to the isozymes LDH1 and LDH2, whose principal subunits are H subunits, and be RPEA of LDH1(H4), LDH2(H3M) increased, while RPEA of LDH5(M4) in various tissues decreased prominently except the cardiac muscle, and that of LDH4(HM3) decreased as well. After polyacrylamide gel electrophoresis (PAGE) of the hypoxia treated cardiac muscle specimen was made, activity subbands originated regularly in the isozyme patterns of LDH, with the regularity of LDH1 (0 subband), LDH2 (0-1 subbands), LDH3(0-2 subbands), LDH4(1-3 subbands), LDH5(2-4 subbands). After adding appropriate amount of NAD^+ to the hypoxia treated cardiac muscle specimen, PAGE showed the subbands of four isozymes (LDH2-LDH5) reduced or even totally disappeared in the isozyme patterns. Conclusions. The negative feedback regulation of coenzymization and decoenzymization of LDH isozymes is one of the mouse stress responses to slight hypoxia.
基金funded by the Applied Fundamental Study of Sichuan Province ( 2008JY0068)China Natural Science Foundation ( 31071700)Funds of the State Ethnic Affairs Commission of PRC ( 08XN04)
文摘[Objective] To express lactate dehydrogenase C (LDH-C) gene in prokaryotic system and then purify the recombinant protein. [Method] The LDH-C gene was amplified from black-lipped pika (Ochotona curzoniae) by RT-PCR and ligated to the expression vector pET-32a. The E. coli BL21 (DE3) carrying the LDH-C gene was obtained and induced by IPTG (isopropy-beta-D-thiogalactoside). The expression products were analyzed by SDS-PAGE and purified by affinity chromatography. [Result] An approximately 1.0 kbp band appeared in the RT-PCR products as theoretically expected. As evidenced by PCR and double enzyme digestion, an approximately 1.0 kbp fragment appeared, which indicated successful construction of expression vector. As analyzed by SDS-PAGE, a fusion protein with molecular weight slightly larger than 45 kDa was expressed in form of inclusion body. And very pure fusion protein was obtained by nickel ions-charged affinity chromatography. [Conclusion] The LDH-C gene of black-lipped pika has been cloned and expressed in E. coli.
文摘Purpose: The LDH isoenzyme patterns were evaluated in lens of fetus to study the metabolism in human lenses.Methods: LDH isoenzyme electrophoresis was performed in 15 lenses of human fetus aged from 4～6 months.Results: There are 5 bands of LDH in fetus lens. LDH4 lever is the highest, and LDH1 is the lowest, especially in the cortex of lens. LDH1 is higher in lens of 4 months of age than in that of 5 and 6 months of age.Conclusions: LDH isoenzyme in lens of fetus shows mainly anaerobic metabolism in development, but there is also aerobic metabolism, especially in younger fetus.
文摘A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chlorides in a drug solution for infusion. Sorbitol, Sodium lactate, and Chloride are all officially recognized in the USP monograph. Assay methods are provided through various techniques, with titrations being ineffective for trace-level quantification. Alternatively, IC, AAS, and ICP-MS, though highly accurate, are costly and often unavailable to most testing facilities. When considering methods, it’s important to prioritize both quality control requirements and user-friendly techniques. A simple HPLC simultaneous method was developed for the quantification of Chlorides, Sorbitol, and Sodium Lactate with a shorter run time. The separation utilized a Shimpack SCR-102(H) ion exclusion analytical column (7.9 mm × 300 mm, 7 μm), with a flow rate of 0.6 mL per min. The column compartment temperature was maintained at 40°C, and the injection volume was set at 10 μL, with detection at 200 nm. All measurements were conducted in a 0.1% solution of phosphoric acid. The analytical curves demonstrated linearity (r > 0.9999) in the concentration range of 0.79 to 3.8 mg per mL for Sodium Lactate (SL), 0.16 to 0.79 mg per mL for Sodium Chloride (SC), and 1.5 to 7.2 mg per mL for Sorbitol. Validation of the developed method followed the guidelines of the International Conference on Harmonization (ICH Q2B) and USP. The method exhibited precision, robustness, accuracy, and selectivity. In accelerated stability testing over 6 months, no significant variations were observed in organoleptic analysis and pH. Consequently, the developed method is deemed suitable for routine quality control analyses, enabling the simultaneous determination of Sodium Lactate, Sodium Chloride, and Sorbitol in pharmaceutical formulations and infusions.
