Placental Microparticles,DNA, and RNA in Preeclampsia

Preeclampsia is a common disorder of the second half of pregnancy that complicates 2% to 7% of all pregnancies worldwide and remains a major cause of maternal and fetal morbidity and mortality. Although the origin of the disease is still elusive, population-based studies have suggested that it might implicate genetic, immunologic, or physiologic factors. On the other hand, there is no doubt that the placenta plays an important role in its development. In preeclampsia, the shedding of placenta debris, such as syncytiotrophoblast microparticles (STBMs) and DNA and messenger RNA molecules, into the maternal peripheral blood is increased. The analysis of this material may give new insight into placentation and the underlying etiology of this disorder, as well as yield new tracks of research for the understanding of the molecular mechanisms, leading to the generation of the clinical symptoms.     

Plasma Peroxyl Radical-Trapping Capacity in Severe Preeclampsia is Strongly Related to Uric Acid

The total peroxyl radical-trapping antioxidant parameter (TRAP) of plasma from nine patients suffering from severe preeclampsia was compared with that from nine control patients sharing the same weeks of pregnancy. Measurement of TRAP was by a new chemiluminescent method. The mean TRAP in preeclamptic patients was 1288 ± 110 µmol/l and in control patients 970 ± 153 µmol/l (p<0.001). TRAP was highly correlated with plasma uric acid (r=0.86), and 91% of the increase in TRAP was due to increase in uric acid, which raises a question of the possible antioxidative role of uric acid in preeclampsia.     

Therapeutic Use of FGA1 Infusions in Severe Pre-Eclampsia-A Major Clinical Potential

Pilot studies showed that, i.v. infusions of the renal prostaglandin A₁ (PGA₁) induced a triad of beneficial clinical responses in severe pre-eclampsia : the blood pressure became normotensive, renal function was markedly improved and labour was successfully induced. The present study was an attempt to develop a therapeutic schedule of PGA₁ administration in severe toxemia. Twenty one cases of severe pre-eclampsia (in 3 equal groups) received i.v. infusions of PGA₁ in a dose range of 0.1–0.5 μg/kgm/min for 12–24 hours and the B.P., uterine activity and FHR were contiuously monitored during and for 12 hours following the infusion period. The 0.1 μg/Kgm/min dose for 12 hours was inadequate while 0.5 μg/Kgm/min for 12 hours induced a good hypotensive response and the cases delivered within 48 hours but a post-infusion rebound in hypertension was observed. The dose of 0.5 μg/Kgm/min for 24 hours appeared to be optimal in clinical terms since a satisfactory effect on B.P. was recorded and all the subjects delivered normal babies during the infusion period with minimal or no post-infusion rebound rise in B.P. This approach holds a major potential in the treatment of severe pre-eclampsia.     

Role of C825T Polymorphism of GNβ3 Gene in Preeclampsia

Objective: The main objective of the study was to understand the role of C825T polymorphism that generates a splice variant in the β3 subunit of heterotrimeric G-protein in preeclampsia. Results: We analyzed genomic DNA of 151 women with preeclampsia (72 Caucasians and 79 African-Americans) and 198 women with normal delivery (102 Caucasians and 96 African-Americans) for C825T polymorphism of GNβ3 gene. The T-allele frequency in Caucasian women with preeclampsia was 0.42 as compared to 0.25 in normal pregnant women (p = 0.0004) and in African-American women with preeclampsia was 0.82 as compared to 0.68 in normal pregnant women (p = 0.0028). Conclusions: Results of these experiments show that the allele frequency of C825T polymorphism is significantly different in women with preeclampsia compared with women with normal delivery in Caucasian as well as African-American population.     

Prediction Tests for Recurrent Hypertensive Disease in Pregnancy,A Systematic Review

Objective. To summarize reported evidence on the performance and clinical usefulness of prediction tests for recurrent hypertensive disease in pregnancy. Methods. A literature search was conducted in MEDLINE/PubMed and EMBASE. Test characteristics were extracted for relevant reports. Results. Thirty-three of 4,311 articles found met the inclusion criteria. Twenty-four potential predictors were identified. Pre-pregnant plasma volume, uterine-artery blood flow velocity profiles, and combined longitudinal patterns of in-pregnancy laboratory variables had reasonable predictive capacity, but also some practical shortcomings. Confidence intervals were often wide. Conclusions. Although evidence points to promising predictive accuracy of some tests, immediate applicability is hampered by statistical imprecision and clinical drawbacks.     

正常妊娠与重度子痫前期孕妇血常规参数的孕期变化对比

目的:比较重度子痫前期孕妇与正常妊娠孕妇在不同孕期下血常规参数的变化并分析其临床意义。方法:选择重度子痫前期孕妇100例为观察组,正常妊娠孕妇100例为对照组,对两组孕妇从妊娠12周起每隔4周进行血常规检查,比较两组的参数变化。结果:观察组与对照组的白细胞计数(WBC)、中性粒细胞比例(N)、淋巴细胞比例(L)在不同孕周间变化不明显,差异没有统计学意义(P>0.05)。相同孕周下两组WBC、N、L的差异没有统计学意义(P>0.05)。对照组的红细胞计数(RBC)、血红蛋白浓度(Hb)、血细胞比容(HCT)在整个妊娠过程中表现出先降低后升高的趋势。观察组RBC、Hb和HCT在不同孕周下没有表现出先降低后升高的趋势。RBC和Hb水平在孕16～35周高于对照组的同期水平,HCT水平在孕20-31周高于对照组的同期水平,差异有统计学意义(P<0.05)。观察组与对照组血小板(PLT)水平在整个妊娠过程中均表现出缓慢下降的趋势,平均血小板体积(MPV)则呈现出逐步上升的趋势。观察组PLT在孕32～39周的水平低于同期对照组的水平,MPV在孕28～35周的水平高于同期对照组的水平,差异有统计学意义(P<0.05)。结论:血常规参数在不同孕周中的变化可以大致反映孕妇的血容量、血黏度以及凝血状态的变化。有望帮助临床早期筛选出重度子痫前期孕妇,及时给予针对性的干预以减轻症状、延缓病情发展。     

Epidemiology of ischemic placental disease: A focus on preterm gestations

Preeclampsia, placental abruption, and intrauterine growth restriction (IUGR) have collectively been termed ischemic placental disease (IPD) due to a suspected common biological pathway involving poor placentation in early pregnancy and subsequent placental insufficiency. Despite decades of research, the etiologies of these conditions remain largely unknown and preventive and therapeutic strategies are lacking. It has been suggested that the underpinnings of IPD lie primarily in preterm gestations and that classification of these conditions based on the gestational age at onset will facilitate etiologic research. The purpose of this review is to describe our current knowledge regarding the risk factors, co-occurrence, and recurrence of the conditions of IPD with a specific focus on the preterm gestational window.