Lack of influence of mild hypothermia on amplitude integrated-electroencephalography in neonates receiving extracorporeal membrane oxygenation

OBJECTIVE: To observe amplitude integrated electroencephalography (aEEG) in neonates receiving ECMO and to determine whether mild hypothermia influenced the aEEG recording. METHODS: Twenty-six consecutive neonates enrolled in a pilot study of mild hypothermia during ECMO were studied. The first group (N=6) was maintained at 37 degrees C throughout the study period. Subsequent groups were cooled to 36 degrees C (N=4), 35 degrees C (N=5), and finally 34 degrees C (N=6) respectively for 24 h and the final group (N=5) to 34 degrees C for 48 h before being rewarmed to 37 degrees C. The aEEG was recorded continuously during the first 5 days of ECMO. The aEEG was classified as normal, moderately or severely suppressed and examined for the occurrence of seizures. To assess the effect of temperature, the aEEG was compared over 12 h during the final 6 h of cooling and during the first 6 h once infants were rewarmed. RESULTS: No change in aEEG amplitude was noted over the temperature range studied. Of the 26 traces obtained, 16 (62%) were normal throughout, 6 (23%) were intermittently moderately abnormal and 1 (14%) was severely abnormal. Three (11%) traces had periods of frequent seizure activity and these were not associated with clinical manifestations in two neonates. In one infant who suffered a cerebral haemorrhage, the aEEG became abnormal before cranial ultrasound abnormalities were apparent. CONCLUSIONS: Continuous cerebral monitoring with aEEG is feasible during ECMO and may add information to clinical examination. Mild hypothermia to 34 degrees C for up to 48 h does not influence the aEEG suggesting that cerebral monitoring with aEEG is possible during mild hypothermia.     

重组人钙调素对精子活动功能的影响

目的：探讨重组人钙调素（ｒｈＣａＭ）对精子活动功能的影响。　方法：用基因工程手段制备并纯化ｒｈＣａＭ。取不育男性精液标本,精子经Ｅａｒｌｅｓ 液处理后,校正精子密度为（５～５０）×１０９／Ｌ,一式３ 份,加入不同浓度的ｒｈＣａＭ,观察不同浓度ｒｈＣａＭ、不同孵育时间对精子运动功能的影响。　结果：２５例活动能力差的精子经孵育１ ｈ,活率未见显著变化（Ｐ＞ ０．０５）,前向运动速度则显著改变（Ｐ＜ ０．０１）,另８ 例活动能力良好的精子,孵育１ ｈ 前向运动速度、活率均无显著性改变（Ｐ＞ ０．０５）。９ 例活动能力差的精子经孵育１ ｈ、２ ｈ 后,活率无显著变化（Ｐ＞ ０．０５）,而前向运动速度、摆幅、鞭打频率改变显著。　结论：外源ｒｈＣａＭ 对精子的活动功能有显著的促进作用,ｒｈＣａＭ 在此过程中可能参与了精子获能前的准备工作。     

猕猴离体心室乳突肌电生理特性研究

作者采用细胞内微电极技术,对8只四川猕猴30个离体心室乳突肌的静息电位、动作电位、超射值、动作电位时程(APD)中的APD_(20)、APD_(50)、APD_(90)、APD_(100),以及0期最大去极速度与有效不应期等电生理活动进行了测量和研究,并比较了猕猴与其他哺乳动物的各项电生理参数。结果表明它们极其相似,故推测它们具有相近的电生理学特性。     

Role of Thromboelastogram in monitoring the activation of the coagulation pathway and assessing the associated risk factors for hypercoagulable state in transfusion dependent thalassemia patients

BackgroundThromboembolic events are rare but one of the fatal complications in thalassemia. Assessment of the hypercoagulable state is not done regularly, and we have assessed the utility of Thromboelastography (TEG) for monitoring the activation of the coagulation pathway in patients with thalassemia.MethodologyA prospective single-center cohort study was conducted in a tertiary care set-up. Transfusion Dependent Thalassemia patients registered with the pediatric unit were screened for hypercoagulability using TEG during six months of the study period and followed up for three years for the development of thromboembolic events. Patient demographics, history of splenectomy, Serum ferritin levels and annual red cell transfusion requirement (mL/kg/year) were assessed. TEG parameters used were R time, K time, alpha angle, Maximum amplitude, Clot index, and Lysis 30. The thrombin generation test (V Curve) obtained from the first-degree derivate of the TEG velocity curve was also used for analysis.ResultsA total of 34 patients were recruited during the six months study period with an average age of 10.6 years ( ± 5.47). The average pre-transfusion hemoglobin level and the volume of packed red cells received were 7.24 g/dL and 152.82 mL/kg/year respectively. The TEG tracing was suggestive of a hypercoagulable state in 58.82% of patients. The mean values of angle (70.74), MA (64.16), CI (2.65) and TG (774.43) in TDT patients compared to age matched reference range (62.81, 57.99, 0.8, 577.83 respectively) was suggestive of prothrombotic changes. Annual blood transfusion requirement was negatively correlated with hypercoagulable status (‐0.344, CI= -0.68 to 0.08). One out of 34 patients developed corona radiata infarct (with annual blood requirement; 112.7 mL/kg/Year). The risk to develop a hypercoagulable state appeared to be higher when the volume of RBCs transfused was less than 154 mL/kg/Year.ConclusionTDT patients are at risk of developing thromboembolism, and screening with TEG may be useful to identify those at high risk.