Preliminary analysis of the association between methylation of the ACE2 promoter and essential hypertension.

The aim of the present study was to investigate whether methylation of the angiotensin I converting enzyme 2 (ACE2) promoter increases the risk of essential hypertension (EH). A total of 96 patients with EH were recruited and 96 sex­ and age­matched healthy controls. Methylation of 5 CpG dinucleotides in the ACE2 promoter was quantified using bisulfite pyrosequencing. Logistic regression and multiple linear regression were used to adjust for confounding factors and the generalized multifactor dimensionality reduction (GMDR) method was applied to investigate high­order interactions. Methylation of CpG4 (adjusted P=0.020) and CpG5 (adjusted P=0.036) was significantly higher in patients with EH, with frequency 97.56±5.65% and 12.75±4.15% in EH individuals and 95.73±9.11% and 11.47±3.67% in healthy controls. GMDR detected significant interaction among the 5 CpG sites (odds ratio=7.33, adjusted P=0.01). Furthermore, receiver operating characteristic curves identified that CpG5 methylation was a significant predictor of EH. Notably, CpG2 methylation was significantly higher in males than in females (adjusted P=0.018). Conversely, CpG5 methylation was significantly lower in males (adjusted P=0.032). These results indicated that aberrant methylation of the ACE2 promoter may be associated with EH risk. In addition, sex may significantly influence ACE2 methylation.

[Effectiveness of preoperative autologous plateletpheresis combined with intraoperative autotransfusion on the blood coagulation in orthopaedic patients].

OBJECTIVE: To investigate the effectiveness of preoperative plateletpheresis combined with intraoperative autotransfusion on the blood coagulation of orthopaedic patients. METHODS: Sixty patients (ASA I-II) undergoing selective orthopaedic surgery were randomized into three groups (n = 20), that is, preoperative plateletpheresis combined with intraoperative autotransfusion for group I, intraoperative autotransfusion for group II, and group III without any managements of blood conservation. Coagulation parameters (prothrombin time, partial thromboplastin time, fibrinogen), hemoglobin and hematocrit values, platelet counts and aggregability were evaluated before the anaesthesia, 10 minutes after plateletpheresis, 10 minutes before the infusion of platelet rich plasma or autologous blood, 10 minutes after infusion, 24 and 48 hours postoperation. Intra- and postoperation blood loss and homologous blood transfusion requirements were also recorded. RESULTS: Among three groups, there were no differences in intraoperative blood loss, perioperative haemoglobin level (Hb and Hct). As compared with group I, significant lower level of platelet counts and aggregability were observed in group II and III at the time of 24 and 48 hours after operation (P < 0.05), while postoperation blood loss and homologous blood-transfusion requirements increased at the same period (P < 0.01). CONCLUSIONS: Preoperative plateletpheresis combined with intraoperative autotransfusion can ameliorate the blood coagulation in orthopaedic patients, and it is an effective way to decrease blood loss and homologous blood-transfusions requirements.