Factors affecting maternal serum magnesium levels during long-term magnesium sulfate tocolysis in singleton and twin pregnancy.

AIM: Our aim was to determine factors that affect maternal serum magnesium (Mg) levels, to help ensure the safety and efficacy of long-term magnesium sulfate (MgSO4 ) therapy for threatened preterm labor in singleton and twin pregnancies. MATERIAL AND METHODS: We retrospectively and arbitrarily studied 100 patients (singleton pregnancy, n = 65; twin pregnancy, n = 35) who received i.v. MgSO4 for >48 h for tocolysis of threatened preterm labor. We used multiple regression analysis to investigate the functional relations between the candidate factors and maternal serum Mg levels. RESULTS: MgSO4 was administered as a loading dose of 3 g for 1 h followed by a maintenance dose of 1.0-2.0 g/h. There were no maternal severe adverse events related to the elevated Mg levels in any of the subjects. The results of multiple regression analysis revealed that total dose of MgSO4 for 24 h before blood collection (g/day), total serum protein level (g/dL), serum total calcium level (mg/dL), serum creatinine level (mg/dL) and maternal bodyweight (kg) significantly affected maternal serum Mg levels in both singleton and twin pregnancies (all P-values were < 0.001). Gestational age (weeks) and period of MgSO4 administration (days) at blood collection had no significant effect in singleton or twin pregnancies. CONCLUSION: Our study statistically shows that dose of MgSO4 , total serum protein level, serum total calcium level, serum creatinine level and maternal bodyweight are key factors to achieving safe and effective long-term tocolysis with MgSO4 in not only singleton but also twin pregnancies.

Transfection of antisense chorionic gonadotropin beta gene into choriocarcinoma cells suppresses the cell proliferation and induces apoptosis.

CONTEXT: Choriocarcinoma cells not only synthesize human chorionic gonadotropin (hCG), but also express LH/CG receptors on the cell membrane. This suggests that the hCG and LH/CG receptors may play a role in regulating the biological function of choriocarcinoma cells in an autocrine/paracrine manner. OBJECTIVE AND METHODS: The objective of this study was to ascertain whether the inhibition of CGbeta gene expression in choriocarcinoma cells affects their proliferation and apoptosis. Expression vector bearing antisense CGbeta gene was transfected into the choriocarcinoma cell line, JAr. CGbeta protein synthesis was monitored by Western immunoblot, and CGbeta mRNA expression was determined by RT-PCR. Cell proliferation was assessed by 3-[4,5-dimethlthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay and nuclear incorporation of 5-bromo-2'-deoxyuridine, and the apoptosis-positive rate was assessed by terminal deoxynucleotidyltransferase-mediated deoxy-UTP nick end labeling analysis and nuclear staining with Hoechst 32258. RESULTS: JAr cells transfected with antisense CGbeta gene (JAr-aCGbeta cells) showed a significant decrease in hCG production and cell proliferation compared with untransfected and mock-transfected cells. The apoptosis-positive rate of the JAr-aCGbeta cells significantly increased compared with that of the controls. LH/CG receptor expression in JAr-aCGbeta cells decreased compared with that in controls. By contrast, supplementation of exogenous hCG significantly increased the LH/CG receptor expression and viability of JAr-aCGbeta cells. CONCLUSIONS: These results suggest that hCG, through its binding to the LH/CG receptor, may augment proliferation and inhibit apoptosis in choriocarcinoma JAr cells, and that the introduction of an antisense gene may be a potential approach to the inhibition of choriocarcinoma cell growth.