腺苷脱氨酶活性检测在胸腔积液诊断中的临床价值

目的探讨腺苷脱氨酶（ADA）活性测定在胸腔积液诊断和抗结核疗效观察中的应用价值。方法采用北京利德曼生物技术有限公司ADA液体试剂盒,对127例胸腔积液患者胸腔积液中ADA活性进行检测,并对44例结核性胸腔积液和83例非结核性胸腔积液进行ADA活性比较及结核性胸腔积液治疗前、后ADA活性变化比较。结果127例患者胸腔积液中ADA活性增高共43例,其中结核组41例,非结核组2例,结核性胸腔积液组ADA活性为（40．67±10．22）U／L,明显高于癌性胸腔积液组[（5．98±5．56）U／L3及炎性胸腔积液组[（6．35±4．65）U／L3,差异有统计学意义（P〈0．05）;ADA诊断结核性胸腔积液的敏感性为93．2％（41／44）,特异性为97．6％（81／83）。结核性胸腔积液患者ADA活性治疗前[（40．67±10．22）U／L3与治疗后[（9．12±6．24）U／L3比较,差异有统计学意义（P〈0．05）。结论胸腔积液ADA活性检测可以作为鉴别结核核性与非结核性胸腔积液的指标,并可作为抗结核治疗疗效观察的指标。     

Relation between maternal serum adenosine deaminase and plasma adenosine levels in twin pregnancies

OBJECTIVE: The relationship between adenosine deaminase activity and plasma adenosine was examined in non-pregnancy as well as in singleton and twin pregnancies. METHODS: Whole-blood samples were taken from 11 singleton and 11 dichorionic twin pregnant women during the third trimester. The plasma adenosine levels were assayed with a modified high-performance liquid chromatographic method, while the adenosine deaminase levels were measured enzymatically. RESULTS: The adenosine deaminase and plasma adenosine levels were both higher in twin pregnancies compared to singleton and non-pregnancies. CONCLUSION: Increased plasma adenosine is not due to decreased serum adenosine deaminase levels in twin pregnant women.     

腺苷脱氨酶检测对结核性脑膜炎诊断的临床价值

目的评价脑脊液中腺苷脱氨酶(ADA)检测对结核性脑膜炎诊断的应用价值。方法采用酶显色法检测102例4组病例(结核性脑膜炎组30例,化脓性脑膜炎组34例,病毒性脑膜炎组15例,头痛症状组23例)脑脊液中ADA的活性水平。结果30例结核性脑膜炎组脑脊液中ADA活性明显增高,ADA6.0U/L26例,与化脓性脑膜炎组比较差异有统计学意义(P0.01),敏感性为86.7%(26/30),特异性为91.7%(66/72)。化脓性脑膜炎组和病毒性脑膜炎组与头痛症状组(对照组)比较差异也具有统计学意义(P0.05)。结论检测脑脊液中ADA的活性对于结核性脑膜炎诊断和鉴别诊断有重要的临床价值。     

Serum adenosine deaminase activity in women with hyperemesis gravidarum

BACKGROUND: Serum adenosine deaminase (ADA) activity increases in diseases where cellular immunity is stimulated. Since hyperemesis gravidarum is characterized by enhanced cell-mediated immunity, serum ADA activity may be altered. The present study evaluated the relation between serum ADA activity and changes in cell-mediated immunity as causes of changes in ADA activity in hyperemesis gravidarum. METHODS: Serum activities of total ADA and its isoenzymes, ADA1 and ADA2, were measured in women with hyperemesis gravidarum (n = 24) and normal pregnancies (n = 24). Peripheral blood lymphocyte and monocyte counts were also measured. RESULTS: In hyperemesis gravidarum, serum total ADA and ADA2 activities averaged 16.8 +/- 0.5 and 13.3 +/- 0.7 U/l, respectively, which were significantly higher than those in normal pregnancies (10.2 +/- 0.5 and 7.8 +/- 0.5 U/l, respectively) (p < 0.05). The mean values for ADA1 activity in women with hyperemesis gravidarum and normal pregnancies were similar. The increase in total ADA activity was accompanied by the increase in lymphocyte and monocyte counts. CONCLUSIONS: These results suggest that increased serum total ADA activity reflects increases in ADA2 activity, which may be at least in part attributed to enhanced cell-mediated immunity in hyperemesis gravidarum.     

Sex differences in adenosine deaminase activity of stroke patients.

BACKGROUND: Adenosine deaminase (ADA) catalyzes the irreversible hydrolytic deamination of adenosine to inosine. The purpose of this study was to determine the plasma activities of total adenosine deaminase (ADA T), and its isoenzymes, ADA1 and ADA2, and ADA1/ADA2 ratio of male and female ischemic stroke patients. METHODS: We determined activities of plasma ADA T, ADA1, ADA2 and ADA1/ADA2 ratio in 30 patients (15 men and 15 women) with acute ischemic stroke within 12 h of the onset of the attack, as well as in 30 control subjects (15 men and 15 women) of comparable age. RESULTS: There were significant differences between the ADA1 activity and ADA1/ADA2 ratio in male and female stroke patients (p<0.05). Compared with male stroke subjects, females had higher ADA1 activity and ADA1/ADA2 ratios. There were no significant differences between activities of ADA T and ADA2 in men and women of the stroke and control groups. In addition, the Canadian Neurological Scale in men was significantly higher than that of women in the stroke group (p<0.05). CONCLUSIONS: Our results suggest that the primary mechanism in men with ischemic stroke might involve the reduction of ADA1 activity. The reduction is probably an adaptation mechanism for induced increase in adenosine availability and protection of brain to ischemic injury.     

Relationship between plasma malondialdehyde levels and adenosine deaminase activities in preeclampsia

BACKGROUND: Preeclampsia is characterized by endothelial cell dysfunction, and lipid peroxidation and alterations of immune responses may be involved in the pathogenesis of this disease. The aim of the present study was to examine changes in plasma malondialdehyde (MDA) level, an indicator of lipid peroxidation, and adenosine deaminase (ADA) activity, as a marker of T-cell activation in preeclampsia, and evaluated the possible relationship between those parameters in the pathogenesis of preeclampsia. METHODS: Plasma levels of MDA, an end product of lipid peroxidation induced by reactive oxygen species, and ADA activities were measured in 26 women with preeclampsia and 26 normal pregnancies. RESULTS: In preeclampsia, plasma MDA level and ADA activity averaged 0.43 +/- 0.03 micromol/l and 15.8 +/- 0.8 U/l, respectively, which were significantly higher than those of normal pregnancy (0.31 +/- 0.02 micromol/l and 9.5 +/ -0.6 U/l, respectively) (P<0.05). In addition, plasma MDA level was positively correlated to ADA activity in preeclampsia (r=0.52, P<0.05). CONCLUSIONS: These results suggest that enhanced lipid peroxidation and T-cell activation, and the presence of possible interrelationship and cross talk between those parameters may be related at least partly to the pathogenesis of preeclampsia.     

Serum adenosine deaminase in normals and in a patient with adenosine deaminase deficient-severe combined immunodeficiency

We have found 50% of normal adenosine deaminase (ADA) activity in the serum from a child with severe combined immunodeficiency (SCID) and genetic complete absence of ADA activity in other tissues (including erythrocytes, mononuclear and cultured cells). We, therefore, investigated properties of normal serum ADA and found that normal serum ADA activity is composed of two ADA isozymes with differing properties. Approximately 25–50% of normal serum ADA activity has properties similar to those of the major ADA isozymes (Ada₁ and ADA_1+CP) which are lacking in children with ADA deficient SCID. The remainder of serum ADA reflects activity of an isozyme with a molecular mass of approximately 100000 dalton. This isozyme has markedly different kinetic properties from those of the major ADA isozymes involved in genetic ADA deficiency. These include a markedly higher K_m for adenosine (2800 μmol/1), a markedly lower ability to deaminate deoxyadenosine than adenosine and a relative insensitivity to inhibition by erythro-9(2-hydroxy-3-nonyl) adenine (EHNA), an inhibitor of the common ADA isozyme(s) (ADA₁ and ADA_{1 + CP}). The properties of this serum ADA isozyme are similar to those of the minor (~2%) ADA isozyme (ADA₂), present in similar amounts in tissues of ADA deficient patients and normals. These findings suggest that the 50% of normal ADA activity observed in serum of an ADA deficient child reflects activity of the 100000-dalton isozyme.     

Diagnostic value of pleural fluid adenosine deaminase activity in tuberculous pleurisy

BACKGROUND: Diagnosis of tuberculous pleuritis is difficult because of its nonspecific clinical presentation and insufficient efficiency of traditional diagnostic methods. We investigated the use of adenosine deaminase (ADA) activity in tuberculous pleuritis diagnosis. METHODS: We optimized a kinetic assay and retrospectively analysed 210 patients with exudative pleural effusions. Using the ROC curve, we determined the optimal cutoff for TB pleurisy. RESULTS: One hundred forty-seven exudative samples were nontuberculous (non-TB) and 63 were tuberculous (TB). There was statistically significant difference (p<0.0001) between the means of pleural fluid ADA levels among the TB and non-TB populations. The disease prevalence of TB pleurisy in the studied population was 30%. The cutoff value for diagnosing TB effusions was >55.8 U/L, with a sensitivity of 87.3% (95% CI: 76.5-94.3%) and specificity of 91.8% (95% CI: 86.2-95.7%). The positive predictive value (PPV) was 82.1% and the negative predictive value (NPV) was 94.4%. A pleural fluid ADA value <16.81 IU/L suggests that a tuberculous effusion is highly unlikely (100% sensitive with 100% NPV and 0% negative likelihood ratio for a pleural fluid ADA level>/=16.81 U/L). In addition, the area under the ROC curve was 0.933 (S.E.=0.0230, 95% CI: 0.890-0.963). CONCLUSION: Pleural fluid total ADA assay is a sensitive and specific test suitable for rapid diagnosis of TB pleurisy.     

肺结核患者外周血腺苷脱氨酶活性与T淋巴细胞亚群定量检测的相关性及临床意义

目的探讨肺结核患者外周血淋巴细胞内腺苷脱氨酶（ADA）活性和T淋巴细胞亚群定量检测的关系及临床意义。方法应用全自动生化分析仪测定肺结核患者血清ADA的活性和用流式细胞仪测定外周血中T淋巴细胞亚群。结果肺结核患者外周血ADA活性显著高于对照组,化疗2个月及6个月后,其活性显著降低,外周血CD4＋、CD8＋及CD4＋／CD8＋比值差异有统计学意义,ADA与CD4＋／CD8＋之间存在相关性。结论肺结核患者淋巴细胞内ADA活性升高与T淋巴细胞亚群比例失调有关,检测患者外周血ADA、T淋巴细胞亚群的变化有助于临床病情监控、疗效判定及预后判断。     

腺苷酸脱氨酶活性对结核性脑膜炎的诊断价值

目的分析脑脊液中腺苷酸脱氨酶活性在结核性脑膜炎中的诊断价值，确定诊断的参考值。方法检测结核性脑膜炎组和非结核性脑膜炎组的脑脊液中ADA的活性，比较两组间的差异；根据不同的临界值计算特异性及敏感性等指标。结果结核性脑膜炎组的ADA活性明显升高。选择腺苷酸脱氨酶活性大于8U／L作为临界值其阳性预测值、阴性预测值、特异性以及敏感性均较高。结论脑脊液中腺苷液脱酶活性对结核性脑膜炎有较大的诊断价值，8U／L作为诊断界值比较合适，大于10U／L基本可以确诊。     

肺结核患者外周血腺苷脱氨酶活性与T淋巴细胞亚群定量检测的相关性及临床意义

目的探讨肺结核患者外周血淋巴细胞内腺苷脱氨酶(ADA)活性和T淋巴细胞亚群定量检测的关系及临床意义。方法应用全自动生化分析仪测定肺结核患者血清ADA的活性和用流式细胞仪(FCM)测定外周血中的T淋巴细胞亚群。结果肺结核患者外周血ADA活性显著高于正常人组,在化疗2个月及6个月后,其活性显著降低(P0.01),外周血CD4、CD8及CD4/CD8比值差异有统计学意义(P0.01),ADA与CD4/CD8之间存在相关性。结论肺结核患者淋巴细胞内ADA活性升高与T淋巴细胞亚群比例失调有关,检测患者外周血ADA、T淋巴细胞亚群的变化有助于临床病情监控、疗效判定及预后判断。     

Syzygium cumini inhibits adenosine deaminase activity and reduces glucose levels in hyperglycemic patients

Syzigium cumini (L.) Skeels from the Myrtaceae family is among the most common medicinal plants used to treat diabetes in Brazil. Leaves, fruits, and barks of S. cumini have been used for their hypoglycemic activity. Adenosine deaminase (ADA) is an important enzyme that plays a relevant role in purine and DNA metabolism, immune responses, and peptidase activity. ADA is suggested to be an important enzyme for modulating the bioactivity of insulin, but its clinical significance in diabetes mellitus (DM) has not yet been proven. In this study, we examined the effect of aqueous leaf extracts of S. cumini ( L. ) (ASC) on ADA activity of hyperglycemic subjects and the activity of total ADA, and its isoenzymes in serum and erythrocytes. The present study indicates that: (i) the ADA activity in hyperglycemic serum was higher than normoglycemic serum and ADA activity was higher when the blood glucose level was more elevated; (ii) ASC (60–1000 μg/mL) in vitro caused a concentration-dependent inhibition of total ADA activity and a decrease in the blood glucose level in serum; (iii) ADA1 and 2 were reduced both in erythrocytes and in hyperglycemic serum. These results suggest that the decrease of ADA activity provoked by ASC may contribute to control adenosine levels and the antioxidant defense system of red cells and could be related to the complex ADA/DPP-IV-CD26 and the properties of dipeptidyl peptidase IV (DPP-IV) inhibitors which serve as important regulators of blood glucose .     

腺苷脱氨酶诊断结核性和恶性胸腔积液价值

目的:探讨胸腔积液和血清中腺苷脱氨酶鉴别诊断结核性胸膜炎及恶性胸腔积液的价值。方法:因胸腔积液住院,经胸腔镜检查和胸膜活检病理确诊为结核性胸腹炎患者(结核组)42例和恶性胸腔积液患者(恶性组)38例,分别检测2组胸腔积液及血清中腺苷脱氨酶活性,应用ROC曲线确定结核性胸膜炎患者胸腔积液腺苷脱氨酶的最佳临界值。结果:结核组胸腔积液腺苷脱氨酶活性、胸腔积液腺苷脱氨酶与血清腺苷脱氨酶比值分别为(48±25)u/L和4.2±3.0,高于恶性组的(20±9)u/L和1.7±1.0,差异均有统计学意义(P<0.01);结核组和恶性组血清腺苷脱氨酶活性分别为(15±6)u/L和(12±5)u/L,差异无统计学意义(P>0.05)。应用ROC曲线确定胸腔积液腺苷脱氨酶诊断结核性胸膜炎的最佳临界值为30.7 u/L,灵敏度为70.5%,特异度为92.2%。结论:胸腔积液腺苷脱氨酶活性可作为鉴别结核性和恶性胸腔积液的重要指标,对结核性胸膜炎有较高的临床诊断价值,而血清腺苷脱氨酶活性对鉴别二者无临床意义。     

Study of the activity of lymphocyte adenosine deaminase in chronic renal failure

The activity of lymphocyte adenosine deaminase was studied in 28 undialysed uremic patients, 19 patients on maintenance hemodialysis and 32 normal subjects. A statistically significant decrease of the enzyme activity was found both for the undialysed and dialysed patients.