Atsushi Miura

Serum adenosine deaminase activity and its isoenzyme pattern in women with normal pregnancies

Abstract. Adenosine deaminase (ADA) is a purine enzyme which is essential for the proliferation, maturation and function of lymphoid cells, and congenital deficiency of this enzyme is associated with severe combined immunodeficiency disease. The activity of ADA has changed in diseases characterized by the alteration of cell-mediated immunity such as rheumatoid arthritis, systemic lupus erythematosus and tuberculosis, so ADA has been considered as a nonspecific marker of cell-mediated immunity. In this study we examined changes in serum total ADA activity and the patterns of two ADA isoenzymes, ADA1 and ADA2 in normal pregnant women, and evaluated the possible role of the alteration of cell-mediated immunity during normal pregnancy as causes of changes in ADA activity. We measured serum activities of total ADA, ADA1 and ADA2 in normal pregnant women in the third trimester (n=24) and age-matched healthy nonpregnant women (n=24). Peripheral blood lymphocytes and monocytes were also measured. In normal pregnant women, serum total ADA activity averaged 10.5 ± 0.5 U/L, which was significantly lower than in nonpregnant women (14.0 ± 0.5 U/L ) (p<0.05), and mean serum ADA2 activity also significantly reduced that of nonpregnant women (p<0.05). There was no significant difference in ADA1 activity in normal pregnant and nonpregnant women. The decrease in total ADA activity was accompanied by the decrease in lymphocyte count. These results suggest that reduced serum total ADA activity reflects decrease in ADA2 activity, and which may be in part associated with depressed cell-mediated immunity during normal pregnancy.

Serum Adenosine Deaminase Activity in Women with Pre-Eclampsia

The present study investigated serum adenosine deaminase (ADA) activity and the patterns of two ADA isoenzymes, ADA1 and ADA2, and to evaluate the possible role of cell-mediated immunity as causes of the changes in ADA activity in pre-eclampsia. We measured serum activities of total ADA, ADA1 and ADA2 in pre-eclampsia (n = 22) and normal pregnancy (n = 22). Peripheral blood monocyte counts and neopterin levels, reflecting the activation of the monocyte-macrophage cell system, were also measured. In pre-eclampsia, serum total ADA and ADA2 activities were significantly increased compared with normal pregnancy (p < 0.05), which were accompanied by increases in serum neopterin levels. These results suggest that increased total ADA activity reflects increases in ADA2 activity, which may be in part related to enhanced cell-mediated immunity during pre-eclampsia.

Relation between adenosine deaminase activities and cytokine-producing T cells in women with preeclampsia

OBJECTIVES To investigate the relation between plasma adenosine deaminase (ADA) activity and cytokine-producing T cells in preeclampsia. DESIGN AND METHODS Plasma ADA activity and the proportions of cytokine-producing T cells were measured in peripheral blood of 28 women with normal pregnancies and preeclampsia. The proportion of CD4-positive T cells producing interferon-gamma and interleukin-4 were analyzed by flow cytometry. RESULTS Plasma ADA activity in preeclampsia was significantly higher than that in normal pregnancy (p < 0.05). In preeclampsia, the proportion of interferon-gamma producing cells significantly increased, and the proportion of interleukin-4 producing cells was significantly decreased compared with normal pregnancy. A significant correlation was found between ADA activity and the proportion of interferon-gamma producing cells in preeclampsia (r = 0.58, p < 0.05). CONCLUSIONS Increased plasma ADA activity in preeclampsia may be in part associated with changes in the proportion of interferon-gamma secreting cells.

Regulation of plasma adenosine levels in normal pregnancy.

The aim of this study was to investigate the possible mechanism of the regulation of plasma adenosine concentration [ADO] in normal pregnancy. We measured the activities of circulating enzymes that are involved in the production and metabolism of adenosine, and plasma [ADO] in nonpregnant (n = 14) and normal pregnant women (n = 14) in the third trimester. In pregnant women, the activity of plasma 5′-nucleotidase and plasma [ADO] were significantly elevated and plasma adenosine deaminase activity was significantly reduced. Enzymatic activities of both plasma enzymes appear to be changed in a way that would favor increased adenosine concentrations.

Changes in the proportion of T helper 1 and T helper 2 cells in cord blood after premature rupture of membranes

Abstract. This study investigated changes in the proportion of T helper (Th)1 and Th2 cells in cord blood after premature rupture of membranes (PROM), and evaluate the effects of PROM on the intrauterine fetal immune status. The proportion of CD3-positive T cells secreting interferon (IFN)-γ as an index of Th1 cells, and interleukin (IL)-4 as an index of Th2 cells in cord blood of 12 newborns with and without PROM, were analyzed by flow cytometry. In cord blood of newborns with PROM, the proportion of IFN-γ secreting cells significantly increased, and the proportion of IL-4 secreting cells was rather high but not significantly higher than that of newborns without PROM. These changes eventually caused a shift in the Th1/Th2 ratio to Th1 dominance in PROM. There was no significant correlation between the proportion of IFN-γ secreting cells and the duration of PROM before the onset of labor. These results suggest that the increase in the proportion of IFN-γ secreting cells after PROM, which eventually cause the Th1/Th2 ratios to show the Th1 predominance, may reflect in part intrauterine fetal immune responses to PROM.

Plasma 5′-Nucleotidase Activities and Uric Acid Levels in Women with Pre-Eclampsia

The present study investigated plasma activity of 5′-nucleotidase, a key enzyme in the production of adenosine, in pre-eclampsia, and evaluated the relationship between changes in 5′-nucleotidase activity, and levels of uric acid, endproduct of the purine metabolism, and the severity of pre-eclampsia. We measured plasma 5′-nucleotidase activities and uric acid levels in women with 18 normal pregnancies, mild and severe pre-eclampsia. In mild and severe pre-eclampsia, plasma 5′-nucleotidase activities and uric acid levels were significantly increased compared with those in normal pregnancy (p < 0.05). Plasma 5′-nucleotidase activity increased according to increases in uric acid levels and the severity of pre-eclampsia. These results suggest that increased plasma 5′-nucleotidase activity may, at least in part, be related to changes in purine metabolism in pre-eclampsia.

Effect of sera on the adhesion of natural killer cells to the endothelium in severe pre‐eclampsia

Objective:  To investigate the effect of serum on the interaction between natural killer (NK) cells and endothelial cells in pre‐eclampsia.

Spontaneous Disruption of the Dividing Membrane in Monochorionic Diamniotic Twin Pregnancy

crit levels of twins A and B at birth were 47.5 and 48.7%, respectively. Cord entanglement ( fig. 2 ) and arterial-arterial anastomoses between the twins were confirmed postnatally. Histopathology confirmed the placentation as monochorionic diamniotic without signs of chorioamnionitis. To date, some possible mechanisms leading to spontaneous antepartum septostomy have been proposed such as infection (chorioamnionitis) [3] , developmental disturbance [3] , trauma or physical rupture by fetuses [4] , and intrauterine sling formation [5] . Recently, however, some cases of monochorionic diamniotic twin pregnancy complicated by spontaneous antepartum rupture of the intertwindividing membrane (and umbilical cord entanglement) without any perinatal episodes have been reported [6–8] . The exact cause of spontaneous antepartum rupture of the dividing membrane could not be well determined. However, in this case one possible reason can be proposed. In this case, the umbilical cord of twin A was located in the center of the placenta and attached to the dividing membrane ( fig. 2 ). Thus, a developmental disturbance resulting in spontaneous septostomy may have occurred in one side of the partitioning membrane due to the attached umbilical cord. This placental condition was also observed in the recent literature with spontaneous antepartum rupture of the dividing membrane [5, 7, 8] . A further study is needed to clarify the mechanism with the accumulation of similar case reports. Dear Editor, In this journal, we have previously reported 2 cases of disruption of the dividing membrane in monochorionic diamniotic twin pregnancy associated with amniocentesis [1] and single intrauterine fetal demise [2] . Recently, we have encountered another case of spontaneous antepartum septostomy without any perinatal episodes in monochorionic diamniotic twin pregnancy. In the current case, fortunately, there were no adverse perinatal outcomes due to a cesarean based on the patient’s request. A 22-year-old woman, gravida 1, para 0, was referred to our hospital at 10 weeks and 5 days’ gestation for a high-risk obstetric consultation due to twin pregnancy. The patient was diagnosed with a monochorionic diamniotic twin pregnancy by ultrasonic examination ( fig. 1 ). In this case, there was no amniocentesis or any other invasive intrauterine procedure performed during the pregnancy. Biweekly ultrasound examinations of the monochorionic diamniotic twin pregnancy were performed until delivery, and the pregnancy had progressed uneventfully. At 36 weeks and 1 day’ gestation, a cesarean section was performed based on the patient’s request. Twin A was a female infant weighing 2,308 g, with Apgar scores of 8 and 9 at 1 and 5 min, respectively, and twin B was a female infant weighing 2,448 g, with Apgar scores of 9 and 9 at 1 and 5 min, respectively. Umbilical artery cord gases in twins A and B had a demonstrated pH level of 7.287 and 7.313, respectively. The hematoReceived: August 22, 2011 Accepted: August 22, 2011 Published online: October 12, 2011

Factors associated with delayed delivery of infant in Cesarean section

transverse incision, the rectus fascia was also incised transversely. During this period, we rarely have used barrier agents for preventing adhesions during Cesarean section. Data are presented as number (%) or mean ± SD. For statistical analysis, the χ 2 test with Yates’ correction for categorical variables was used while the Student’s t-test for continuous variables was used. Differences with p < 0.05 were considered significant. Table I shows maternal height and weight at delivery, neonatal birth weight and incision-to-delivery time of the first or second non-urgent Cesarean deliveries between 2008 and 2010. There were no significant differences in the average maternal height and weight at delivery and neonatal birth weight in the 6 groups in Table I. The average incision-to-delivery intervals by transverse incision at non-urgent repeat Cesarean deliveries were longer significantly than those by vertical incision irrespective of number of Cesarean delivery or adhesion in the abdominal cavity. In addition, the average incision-to-delivery intervals with severe adhesions were longer significantly than those without severe