Role of CD73 in endogenous protective mechanism of hepatic ischemia-reperfusion injury in mice and the relationship with TGF-β 1/Smad3 signaling pathway / 中华麻醉学杂志

Objective:To evaluate the role of ecto-5′-nucleotidase (CD73) in endogenous protective mechanism of hepatic ischemia-reperfusion (I/R) injury in mice and the relationship with transforming growth factor beta1 (TGF-β 1)/Smad3 signaling pathway. Methods:Twenty-four SPF healthy male C57BL/6 mice, aged 8-10 weeks, weighing 20-23 g, were divided into 3 groups ( n=8 each) by the random number table method: sham operation group (S group), hepatic I/R group (IR group) and hepatic I/R plus CD73 specific inhibitor group (APCP group). The hepatic hilum was only exposed but not occluded in group S. The hepatic portal was occluded for 30 min followed by reperfusion to develop the model of hepatic I/R in anesthetized animals in group IR.CD73-specific inhibitor APCP 40 mg/kg was intraperitoneally injected, and 10 min later hepatic I/R was performed.Orbital venous blood samples were collected at 6 h of reperfusion for determination of serum alanine transaminase (ALT) and aspartate transaminase (AST) concentrations.Then the mice were sacrificed, and liver tissues were obtained for determination of the expression of CD73, TGF-β 1 and phosphorylated Smad3 (p-Smad3) (by Western blot), contents of interleukin-1β (IL-1β) and tumor necrosis factor-alpha (TNF-α) (by enzyme-linked immunosorbent assay), and content of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) (with a visible spectrophotometer) and for microscopic examination of the pathological changes of liver tissues (with a light microscope). Results:Compared with group S, the concentrations of AST and ALT in serum and contents of IL-1β, TNF-α and MDA in liver tissues were significantly increased, the activity of SOD was decreased, and the expression of CD73, TGF-β 1 and p-Smad3 was up-regulated in IR and APCP groups ( P<0.05). Compared with group IR, the concentrations of AST and ALT in serum and contents of IL-1β, TNF-α and MDA in liver tissues were significantly increased, the activity of SOD was decreased, and the expression of CD73, TGF-β 1 and p-Smad3 in liver tissues was down-regulated in group APCP ( P<0.05). The pathological changes of liver tissues were accentuated in group APCP as compared with group IR. Conclusions:CD73 is involved in the process of endogenous protective mechanism of hepatic I/R injury in mice, which may be related to the regulation of TGF-β 1/Smad3 signaling pathway.

Progress of CD73 in tumor immune microenvironment / 肿瘤研究与临床

Extracellular 5'-nucleotidase (CD73) is not only highly expressed in a variety of solid tumor tissues, but also closely related to tumor stage, treatment and tumor prognosis. CD73 can exert a wide range of immunosuppressive effects through multiple pathways such as A2A receptor, regulation of regulatory T cells, and inhibition of inflammation. Blocking CD73 molecules can not only effectively activate anti-tumor immune responses, but also significantly improve the clinical efficacy of programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) antibodies. Thus, CD73, as a new immunological checkpoint molecule in the tumor microenvironment, may become a promising new immunotherapy target following CTLA4, PD-1/PD-L1.

Neutralization of anti-venom IgY against main activities of Deinagkistrodon acutus venom / 中国药理学通报

Aim To evaluate the potency of anti-D. acutus venom IgY neutralizing the main activities of D. acutus venom.Methods After mixing the different a-mounts of IgY with snake venom and incubating togeth-er,the main activities of snake venom were assayed by biochemical methods.Results The in vitro assays in-dicated that anti-D.acutus venom IgY obviously neu-tralized the activities of PLA2 ,5′-nucleotidase,hyalu-ronidase,metalloprotease and serine proteinase (fi-brinogenase)in D.acutus venom.Mouse experiments showed that the ED50 value of IgY for mouse was 1 131.09 μg.Conclusion Anti-D.acutus venom IgY antibodies have good effects in neutralizing D.acutus venom without the toxicities themselves.

Matrix metalloproteinase-9 regulates the shedding of CD73 from retinal pigment epithelium / 中华眼底病杂志

Objective To study how CD73 is shed from the retinal pigment epithelium (RPE) surface. Methods CD73 shedding was induced by treating RPE with lipopolysaccharides (LPS) and TNF-α. After Phospholipase C (PLC) or pan matrix metalloproteinase (MMP) inhibitors were added, surface amount of CD73 was evaluated by flow cytometry (FACS). Then selective inhibitors or their corresponding siRNAs of MMP-2 and MMP-9 were applied to the treatments of RPE; and their effects on induced CD73 shedding were evaluated by FACS. By site directed mutagenesis, mutations were introduced to Lys547-Phe548 coding sites of CD73 cDNA, which was cloned in a pcDNA mammalian expression vector. Both wt-CD73 and mutated-CD73 were over expressed in CD73-/- RPE and their induced shedding was compared. Results LPS and TNF-α induced CD73 shedding from RPE was completely blocked by the addition of pan MMP inhibitor but not PLC inhibitor. Selective MPP-9, but not MMP-2, inhibitor or its siRNA blocked CD73 shedding. In CD73-/- RPE induced CD73 shedding was happened to overexpressed wt-CD73 but not Lys547-Phe548 sites mutant CD73. Conclusion MMP-9 is responsible for shedding CD73 from RPE through hydrolyzing its Lys547 -Phe548 sites.

Matrix metalloproteinase-9 regulates the shedding of CD73 from retinal pigment epithelium / 中华眼底病杂志

Objective To study how CD73 is shed from the retinal pigment epithelium (RPE) surface. Methods CD73 shedding was induced by treating RPE with lipopolysaccharides (LPS) and TNF-α. After Phospholipase C (PLC) or pan matrix metalloproteinase (MMP) inhibitors were added, surface amount of CD73 was evaluated by flow cytometry (FACS). Then selective inhibitors or their corresponding siRNAs of MMP-2 and MMP-9 were applied to the treatments of RPE; and their effects on induced CD73 shedding were evaluated by FACS. By site directed mutagenesis, mutations were introduced to Lys547-Phe548 coding sites of CD73 cDNA, which was cloned in a pcDNA mammalian expression vector. Both wt-CD73 and mutated-CD73 were over expressed in CD73-/- RPE and their induced shedding was compared. Results LPS and TNF-α induced CD73 shedding from RPE was completely blocked by the addition of pan MMP inhibitor but not PLC inhibitor. Selective MPP-9, but not MMP-2, inhibitor or its siRNA blocked CD73 shedding. In CD73-/- RPE induced CD73 shedding was happened to overexpressed wt-CD73 but not Lys547-Phe548 sites mutant CD73. Conclusion MMP-9 is responsible for shedding CD73 from RPE through hydrolyzing its Lys547 -Phe548 sites.

Abnormal NT5C2 gene expression in acute lymphoblastic leukemia / 中华检验医学杂志

Objective To investigate the expression and significance of mRNAand exon mutationof NT5C2 gene in acute lymphoblastic leukemia (ALL) bone marrow.Methods Case control study design was used in this study.Bone marrow samples were collected from ALL patients in Anhui Provincial Cancer Hospital in recent 4 years.The patientswere divided into the initial diagnosis group , the complete remission group and the recurrence group.And they could specifically be divided into 36 patients initially diagnosed, 36 patients who achievedcomplete remission and 16 patients who relapsed with children B -ALL,15 patients initially diagnosed,15 patients who achievedcomplete remission and 9 patients who relapsed with children T -ALL, 18 patients initially diagnosed,18 patients who achievedcomplete remission and 12 patients who relapsed with adult B-ALL, and 11 patients initially diagnosed,11 patients who achievedcomplete remission and 6 patients who relapsed with adult B -ALL.The initial diagnosis,complete remission and recurrence samples were matched.8 children and 8 adults without hematologic malignanciewere used as controls .Real-time PCR was performed to detect the level of NT5C2 mRNAin ALL patients.The exons of NT5C2 gene were cloned and sequenced for the common mutations in all cases .The results of NT5C2 mRNA levels in different groups were performed using non -parametric test by SPSS16.0 analytics software, and then non-parametric test together with correlation analysis was analyzed between NT 5C2 mRNA levels of different initial diagnosis groups and gender, age, leukocyte level and risk classification .Results (1)The expression of NT5C2 mRNA levels of recurrence group were higher than that of initial diagnosis group ,complete remission group and controls in children and adult B -ALL respectively(P 0.05).(3)NT5C2 mRNA expression of initial diagnosis group in children and adult B -ALL and T-ALL was not correlated with risk classification (P >0.05).(4)A newheterozygousmutation p.P414A of NT5C2 was discovered in a recurrencesample.Conclusions (1) High expression ofNT5C2 mRNA is associated with recurrence inchildren and adult B-ALL, and it may be an indicator of monitoring recurrence .(2)The incidence of exons mutation of NT5C2 gene in ALL is low in China.

Application of serum alpha-fetoprotein, α-L-fucosidase, 5'-nucleotidase and γ-glutamyltransferase in early diagnosis of hepatocellular carcinoma / 肿瘤研究与临床

Objective To investigate the application of alpha-fetoprotein (AFP),α-L-fucosidase(AFU),5'-nucleotidase(5'-NT) and γ-glutamyltransferase (GGT) in diagnosis of hepatocellular carcinoma(HCC),and to provide the basis for its early and rapid diagnosis.Methods The clinical data of 120 cases with initial diagnosis as hepatocellular carcinoma,150 cases with liver cirrhosis,200 cases with hepatitis were analyzed retrospectively from June 2013 to August 2014,meanwhile,100 healthy people were selected as control group.The serum AFP,AFU,5'-NT and GGT levels were measured by electrochemiluminescence immunoassay,rate method,peroxidase method and enzymatic colorimetric assay,respectively.The results were analyzed by receiver operating characteristic (ROC) curve,while the sensitivity,specificity,AUC were calculated at the same time.Results The levels of serum AFP,AFU,5'-NT and GGT were significantly different among HCC group,liver cirrhosis group,hepatitis group and control group (all P＜0.05).When tested alone,the sensitivities of AFP,AFU,5'-NT and GGT were 58.33 ％(70/120),82.50 ％(99/120),85.00 ％(102/120),78.33 ％(94/120),the specificities were 88.33 ％(106/120),73.33 ％(88/120),88.33 ％(106/120),71.67 ％(86/120),and AUC were 0.655,0.702,0.814,0.754.When four indexes were performed with combined test,the sensitivity was 98.33 ％(118/120),specificity was 96.67 ％(116/120),AUC was 0.975,which were higher than the single detection (all P＜0.05).Conclusion The combined detection of serum AFP,AFU,5'-NT and GGT can greatly increase the sensitivity and specificity for diagnosing HCC and will gain mutual complement advantages,which is of great clinical value for early and rapid diagnosis.

Expression and clinical significance of CN-Ⅱ in non-small cell lung cancer tissues / 中国肿瘤临床

Objective:Cytosolic 5'-nucleotidase (CN-Ⅱ), a nucleotide kinase, exhibits both 5'-nucleotidase and nucleoside phos-photransferase activities. Abnormal CN-Ⅱexpression may be correlated with the resistance of nucleoside analogs in anticancer drugs. This study was designed to investigate CN-Ⅱexpression in human non-small cell lung cancer (NSCLC) tissues and its correlation with the clinicopathological parameters as well as the prognosis of patients treated with gemcitabine. Methods:Immunohistochemistry was used to detect CN-Ⅱexpression in 116 cases of paraffin-embedded NSCLC samples. The correlations with the clinicopathological pa-rameters and the response to gemcitabine chemotherapy of CN-Ⅱwere analyzed through the Chi-square test. Log-rank test was used to determine whether or not CN-Ⅱexpression is correlated with the overall survival of patients. Results:The positive rate of CN-Ⅱwas 53.4% in 116 NSCLC tissues. No significant correlation existed between CN-Ⅱ expression and the clinicopathological parameters. Among the 67 of the 116 patients who received gemcitabine chemotherapy, those with tumor progression (positive rate of 57.6%) exhib-ited higher CN-Ⅱexpression than those with therapeutic efficacy (positive rate of 30.4%, P=0.008) and disease-control chemotherapy (positive rate of 36.7%, P=0.013). The progression-free survival was 4.5 and 5.5 months in the CN-Ⅱ-positive and CN-II-negative groups, respectively, with significant differences (95%CI:4.452 to 6.148, P=0.041). Correspondingly, the overall survival was 9.5 and 11.0 months in the two groups (95%CI:8.667 to 13.333, P=0.282). Conclusion:CN-Ⅱmay be a prognostic factor for gemcitabine chemotherapy in NSCLC patients.

Study the effect of kidney stones on serum xanthine oxidase, ecto-5'-nucleotidase activity and E3 SUMO-protein ligase NSE2 (NSMCE2) in Malaysian individuals

Objective: To verify possible relations between 5'-nucleotidase, xanthine oxidase to E3 small ubiquitin-like modifier-protein ligase non structural maintenance of chromosomes elements 2 in sera patients with kidney stones and to evaluate the possibility of a new biomarker for the evaluation of kidney damage. Methods: A sixty patients with known kidney stones who appeared the government health clinics in Kuantan-Pahang and fifty apparently healthy were taken as control group. The 5'- nucleotidase, xanthine oxidase and other biochemical parameters were measured by colorimetric tests. The serum NSMCE2 were measured by enzyme linked immunosorbent assay. Results: The mean serum xanthine oxidase [(39.98 ± 19.70) IU/L] and ecto-5'-nucleotidase activity (40.03 ± 9.53 IU/L) were significantly higher than the controls' levels of (18.04 ± 6.26) and (16.06 ± 4.61) IU/L respectively. There were 85.00% and 83.33%, of patients with kidney stones who had abnormal ecto-5'-nucleotidase activity and uric acid respectively while xanthine oxidase activity was less sensitive 58.33%. Conclusions: The present study suggests that the increase in serumof xanthine oxidase,ecto- 5'-nucleotidase activities E3 small ubiquitin-like modifier-protein ligase NSE2 concentration can be used as biomarkers for diagnosis of kidney damage in patients with kidney stone, also in developments of change DNA damage and inflammation disorders in these patients.

Clinical application of combined detection of serum Cys-C, 5'-NT and AFP in hepatocellular carcinoma / 肿瘤研究与临床

Objective To explore the clinical application of single or combined detection of serum Cys-C,5'-NT and AFP in hepatocellular carcinoma (HCC) in order to provide the platform for early diagnosis and prognosis evaluation.Methods The serum levels of Cys-C,5'-NT and AFP from 148 cases of HCC patients (HCC group),135 cases of liver cirrhosis patients (LC group) and 155 cases of hepatitis (hepatitis group) and 100 healthy people (control group) were measured by latex-enhanced immunoturbidimetric assay (LEITD),peroxidase method and electrochemiluminescence immunoassay (ECLI),respectively.Then their differences had been compared.The sensitivity,specificity and Youden's index were calculated and the results were analyzed by receiver operating characteristic (ROC) curve.Results The levels of serum Cys-C,5'-NT and AFP were significantly different in 4 groups.The differences were statistically significant (F =12.35,42.25,58.12,P =0.000).The sensitivity of three indicators for diagnosing HCC was 100 ％,which was higher than that of single or two combined detection (P ＜ 0.05),and the specificity was 78.97 ％.The area under ROC curves of combined detection of three indicators was 0.977,which was also higher than single or two combined detection (P ＜ 0.05).Conclusions The combined detection of serum Cys-C,5'-NT and AFP can greatly increase the sensitivity and accuracy for diagnosing HCC,which has an important clinical value for early diagnosis.Therefore it is worth popularizing and applying on clinic.

Comparative Study of Serum Gamma Glutamyltransferase, 5’ Nucleotidase and Alkaline Phosphatase in Icteric and an-Icteric Biliary Disease Patients

Diagnostic enzymology plays a useful role in evaluation of various hepatobiliary diseases and numerous enzymes have been compared in different disorders. Among these, significance of Gamma Glutamyl Transferase and 5’ Nucleotidase over Alkaline Phosphatase has been stressed repeatedly, but mainly in the icteric obstructive biliary disease patients. In this study, these three enzymes were compared not only in the icteric but also the an-icteric biliary disease patients, particularly to look for elevation and significance of these enzymes in the latter group. Methods: The study was conducted on 50 biliary disease patients, who were further divided into an-icteric (32 patients) and icteric (18 patients) subgroups depending on their bilirubin levels. 50 subjects matched for age and sex with the study group were enrolled for the control group. Gamma Glutamyl Transferase, 5’Nucleotidase, Alkaline Phosphatase and bilirubin levels were evaluated in all the patients as well as the control subjects. Results: All three enzymes showed a significant rise in the icteric subgroup (p value < 0.001). However, in the an-icteric subgroup, only Gamma Glutamyl Transferase and 5’Nucleotidase showed a significant rise. The rise was more for Gamma Glutamyl Transferse (1.60 times normal, p < 0.001) as compared to 5’Nucleotidase (1.39 times normal, p < 0.01). Conclusion: Gamma Glutamyl Transferase and 5’Nucleotidase are useful for evaluation of not only obstructive biliary disease patients but also for the patients with biliary disease who are an-icteric, and out of these two, the former is a more valuable diagnostic indicator in such diseases.

Analysis of the NTPDase and ecto-5'-nucleotidase profiles in serum-limited Trichomonas vaginalis

Trichomonas vaginalis is a parasite of the human urogenital tract that causes trichomonosis, the most prevalent non-viral sexually transmitted disease. Ectonucleoside triphosphate diphosphohydrolase (NTPDase) family members, which hydrolyse extracellular ATP and ADP and ecto-5′-nucleotidase, which hydrolyses AMP, have been characterised in T. vaginalis. For trichomonad culture, the growth medium is supplemented with 10 percent serum, which is an important source of nutrients, such as adenosine. Here, we investigated the ATP metabolism of T. vaginalis trophozoites from long-term cultures and clinical isolates under limited bovine serum conditions (1 percent serum). The specific enzymatic activities were expressed as nmol inorganic phosphate (Pi) released/min/mg protein, the gene expression patterns were determined by reverse transcriptase-polymerase chain reaction, the extracellular adenine nucleotide hydrolysis was analysed by high performance liquid chromatography and the cell cycle analysis was assessed by flow cytometry. Serum limitation led to the profound activation of NTPDase and ecto-5'-nucleotidase activities. Furthermore, the levels of NTPDase A and B transcripts increased and extracellular ATP metabolism was activated, which led to enhanced ATP hydrolysis and the formation of ADP and AMP. Moreover, the cell cycle was arrested at the G0/G1 stage, which suggested adenosine uptake. Our data suggest that under conditions of serum limitation, NTPDase and ecto-5'-nucleotidase play a role in providing the adenosine required for T. vaginalis growth and that this process contributes to the establishment of parasitism.

Red Blood Cell Enzymopathies Causing Hereditary Hemolytic Anemia / 임상소아혈액종양

The RBC enzyme deficiencies causing hereditary hemolytic anemia (HHA) can be divided into three groups: those participating in the glycolytic (E-M) pathway; those involved with the maintenance of a high ratio of reduced to oxidized glutathione; one enzyme in the nucleotide degradation and salvage pathway. Although RBC enzyme deficiencies causing HHA are rare, 3 of the 15 kinds of important and relatively frequently reported enzyme deficiencies such as pyruvate kinase, glucose-6-phosphate-dehydrogenase and pyrimidine-5'-nucleotidase deficiencies are briefly reviewed. The molecular genetics, clinical symptoms, diagnosis and therapeutic approaches of each enzyme deficiencies are summerized. As these enzyme deficiencies are reported throughout the world as well as in Korea with the identification of the mutations, considering a broad spectrum of etiologies for the diagnosis of HHA seems to be warranted.

Overexpression of CD73 in epithelial ovarian carcinoma is associated with better prognosis, lower stage, better differentiation and lower regulatory T cell infiltration / 부인종양

OBJECTIVE: The purpose of the current study was to evaluate survival outcome according to the expression status of CD73 in patients with epithelial ovarian cancer. METHODS: A total of 167 patients with epithelial ovarian cancer were enrolled in the current study. For each patient, a retrospective review of medical records was conducted. Immunohistochemical staining for CD73, CD8, FoxP3, and CD68 was performed using tissue microarray made with paraffin embedded tissue block. RESULTS: Among the enrolled patients, 29.9% of patients (n=50) showed negative expression for CD73, whereas 70.1% of patients (n=117) showed positive expression for CD73. The CD73 positive group showed better prognosis compared to the CD73 negative group (5-year overall survival of CD73 positive group, 73.0%; that of CD73 negative group, 50.1%; p=0.023). CD73 was more frequently expressed in mucinous adenocarcinoma and clear cell carcinoma compared to serous or endometrioid adenocarcinoma. In addition, CD73 overexpressions were more frequently detected in patients with known good prognostic factors, i.e., low stage, well/moderate differentiation, negative peritoneal cytology, no lymphovascular involvement, and no macroscopic residual tumor after debulking surgery. There was significantly more infiltration of regulatory T cells in the CD73 negative group compared to the CD73 positive group. CONCLUSION: Good prognosis in patients with overexpression of CD73 may be due to that overexpression of CD73 was more frequently observed in epithelial ovarian cancer patients with known good prognostic factors. Therefore, this result means that favorable differentiation and stage have more influence on survival outcome than adverse effect of CD73 per se.

Overexpression of CD73 in epithelial ovarian carcinoma is associated with better prognosis, lower stage, better differentiation and lower regulatory T cell infiltration / 부인종양

OBJECTIVE: The purpose of the current study was to evaluate survival outcome according to the expression status of CD73 in patients with epithelial ovarian cancer. METHODS: A total of 167 patients with epithelial ovarian cancer were enrolled in the current study. For each patient, a retrospective review of medical records was conducted. Immunohistochemical staining for CD73, CD8, FoxP3, and CD68 was performed using tissue microarray made with paraffin embedded tissue block. RESULTS: Among the enrolled patients, 29.9% of patients (n=50) showed negative expression for CD73, whereas 70.1% of patients (n=117) showed positive expression for CD73. The CD73 positive group showed better prognosis compared to the CD73 negative group (5-year overall survival of CD73 positive group, 73.0%; that of CD73 negative group, 50.1%; p=0.023). CD73 was more frequently expressed in mucinous adenocarcinoma and clear cell carcinoma compared to serous or endometrioid adenocarcinoma. In addition, CD73 overexpressions were more frequently detected in patients with known good prognostic factors, i.e., low stage, well/moderate differentiation, negative peritoneal cytology, no lymphovascular involvement, and no macroscopic residual tumor after debulking surgery. There was significantly more infiltration of regulatory T cells in the CD73 negative group compared to the CD73 positive group. CONCLUSION: Good prognosis in patients with overexpression of CD73 may be due to that overexpression of CD73 was more frequently observed in epithelial ovarian cancer patients with known good prognostic factors. Therefore, this result means that favorable differentiation and stage have more influence on survival outcome than adverse effect of CD73 per se.

Red Blood Cell Enzymopathies Causing Hereditary Hemolytic Anemia / 임상소아혈액종양

The RBC enzyme deficiencies causing hereditary hemolytic anemia (HHA) can be divided into three groups: those participating in the glycolytic (E-M) pathway; those involved with the maintenance of a high ratio of reduced to oxidized glutathione; one enzyme in the nucleotide degradation and salvage pathway. Although RBC enzyme deficiencies causing HHA are rare, 3 of the 15 kinds of important and relatively frequently reported enzyme deficiencies such as pyruvate kinase, glucose-6-phosphate-dehydrogenase and pyrimidine-5'-nucleotidase deficiencies are briefly reviewed. The molecular genetics, clinical symptoms, diagnosis and therapeutic approaches of each enzyme deficiencies are summerized. As these enzyme deficiencies are reported throughout the world as well as in Korea with the identification of the mutations, considering a broad spectrum of etiologies for the diagnosis of HHA seems to be warranted.

The effect of 5'-nucleotidase from Trimeresurus albolabris venom on platelet aggregation and its mechanism / 中国生化药物杂志

Purpose To investigate the effect of 5'-nucleotidase from Trimeresurus albolabris venom on platelet aggregations and its mechanism.Methods Piatelet aggregations induced by ADP,AA and PAF,respectively.were measured by turbidimetric method after platelet incubated with 5'-nucleotidase.Results 5'-nucleotidase significantly inhibited platelet aggregations induced by ADP,AA and PAF in a dose-dependent manner.Washed platelet inhibition experiment and the effect of Adenosine,CP/CPK on platelet aggregations showed that platelet aggregations inhibited by 5'-nucleotidase were associated with ADP hydrolysis and adenosine accumulation.The effect of ASA on platelet aggregations showed that the enzyme inhibited platelet aggregations probably by blocking the formation of TXA2.Conclusion 5'-nucleotidase from Trimeresurus albolabris venom inhibited platelet aggregations through ADP hydrolysis and adenosine accumulation,and maybe it is related to blocking the formation of TXA2.

Hypoxia upregulates CD73 expression in mouse microvascular endothelial cells / 中国病理生理杂志

AIM: To study the effect of hypoxia on CD73 expression in mouse microvascular endothelial cell line bEnd.3. METHODS: ① bEnd.3 cells were exposed to different periods of hypoxia. ② Concentration of LDH released by bEnd.3 cells into the culture medium was detected. ③ Surface CD73 activity in bEnd.3 cells was measured by HPLC according to the conversion of E-AMP to E-ADO. ④ CD73 mRNA expression were analyzed by semiquantitative RT-PCR. ⑤ Cell surface proteins were biotinylated and CD73 was detected by avidin blots of immunoprecipitation with mAb TY23. RESULTS: ① bEnd.3 cells exposed to hypoxia for 24 h demonstrated a significant increase in LDH release (P

A Study of the Correlation Between the Activity of Erythrocyte Pyrimidine 5'-Nucleotidase and Urinary N-Acetyl-beta-D-Glucosaminidase in Lead Exposed Workers / 대한산업의학회지

In this study, we measured the activity of the erythrocyte pyrimidine 5'-nucleotidase (P5N) and urinary N-acetyl-beta-D-glucosaminidase (NAG) from 154 workers exposed to lead and 43 workers not exposed. We analyzed the correlation of the P5N activity and NAG activity with other biological exposure indices of lead such as blood lead (PbB) and zinc protoporphyrin (ZPP). The measurement was performed by using high performance liquid chromatography (HPLC), spectrophotometer and atomic absorption spectrophotometer. The results are as follows: 1. The mean value of P5N activity for workers exposed to lead was 9.50+/-.13 micromol uridine/hr/g Hb and 11.60+/-.2 micromol uridine/hr/g Hb for workers not exported. The P5N activity showed a normal distribution, but the other indices of lead showed logarithmic normal distributions. 2. The P5N activity and ZPP were decreased as PbB wag increased. But the NAG activity had no correlation with changes of PbB. 3. The correlation coefficients of the P5N activity with other biological exposure indices of lead such as PbB, ZPP, NAG activity were -0.72, -0.55, and 0.05, respectively. We speculated that the P5N activity can be used as a reliable biological exposure index of lead but NAG activity can be used as a biological management index of lead.

Comparison of Blood Pre-treatment Methods for Determining Erythrocyte Pyrimidine 5'-Nucleotidase Activity / 대한산업의학회지

Sakai's method has been known as the simplest one for determination of erythrocyte pyrimidine 5'-nucleotidase (P5N) activity using high performance liquid chromatography(HPLC). However the drawback of the method is that it is difficult to wash the erythrocyte for isolation. To search for the simpler method, we compared Sakai's method with other methods using whole blood treated with heparin and concanavalin A or whole blood treated with EDTA-2K instead of washing the erythrocyte. The mean concentrations of lead in blood samples collected from 44 male and 16 female workers who are healthy without any exposure to lead in their workplace were 4.30 +/- 1.31 microgram /dl (mean +/-standard deviation), which were measured by frameless atomic absorption spectrophotometer. Erythrocyte P5N activities were measured by 3 methods; Sakai's method(Method I), using whole blood treated with heparin and concanavalin A (Method II), and using whole blood treated with EDTA-2K (Method III). The results were obtained as follows ; 1. The mean of erythrocyte P5N activity by Sakai's method(Method I) were 12.7 +/-2.47 amole uridine/hr/gm of Hb. 2. The mean of erythrocyte P5N activity by the method using heparinized whole blood treated with concanavalin A(Method II) were 13.1 +/-2.41 micromole uridine/hr/gm of Hb. 3. The difference of mean erythrocyte P5N activity between Method I and Method was not significant. 4. The erythrocyte P5N activity by the method using whole blood treated with EDTA-2K (Method III) was significantly different from Method I. We thought that omission of incubation period which was required on Method III using EDTA-2K caused the difference between Method I and Method III. 5. Simple linear regression equation for erythrocyte P5N activity between Method I (Y) and Method II(X) was significant: Y = -0.012 + 0.9724 X. These results suggest that the method using whole blood treated with heparin and concanavalin A is simpler to examine the erythrocyte P5N activity as a biological indicator of lead intoxication than Sakai's method.