The effects of estrogen and raloxifene treatment on antioxidant enzymes in brain and liver of ovarectomized female rats

Recent studies documented that estrogen have antioxidant properties in-vitro, there are conflicting results on the effect of estrogen in vivo. We aimed to investigate the effects of estradiol and Raloxifene on the antioxidant enzyme [superoxide dismutase (SOD) and catalase (CAT)] activities and MDA levels in brain and liver homogenates of ovariectomized female rats. Twelve weeks after ovariectomy, female Sprague-Dawley rats (n = 26) were divided into three groups: (1) Ovariectomized placebo group (n = 6) was given physiologic saline. (2) Estrogen group (n = 10) was given Ethynyl estradiol, 0.1 mg/kg sc. (3) Raloxifene group (n = 10) was given raloxifene, 1 mg/kg sc during 8 weeks. Ten rats were used as naive controls without any treatment (Sham operated group, n = 10). Ovariectomy lead to an increase in the CAT activities in liver tissue samples compared to the sham group (p = 0.056, Mann-Whitney test). While estrogen treatment reversed to normal levels of CAT activities, raloxifene remained as ineffective. Superoxide dismutase activities and MDA levels in liver were remained unchanged in all groups. There was no significant change in the brain tissue SOD and CAT activities between the control ovariectomy, estrogen treated, and raloxifen treated groups. We determined an increase in MDA levels in brain of ovariectmised rat (p = 0.02). While raloxifene treatment reversed to normal levels of MDA (p = estrogen treatment failed. Our data showed that estrogen may play a role in regulation of CAT and SOD activities in liver due to its antioxidative effects. We can suggest estrogen and raloxifene exert their antioxidative effects in brain rather than liver. Since Raloxifene's effect is more clear than estradiol, raloxifene may be suggested primarily for treatment and/or prevention of diseases which can be resulted from oxidative stress in postmenopausal women.     

Evaluation of sprint exercise testing protocols in wheelchair athletes

STUDY DESIGN: Comparison of five different exercise testing protocols with different speeds on a treadmill with seven wheelchair athletes. OBJECTIVE: To determine which speed and duration in an exercise protocol is best to test wheelchair athletes performing sprint races on a track. SETTING: Swiss Paraplegic Centre, Nottwil, Switzerland. METHODS: Three elite and four junior wheelchair athletes (18.7+/-6.8 years, 52.1+/-9.7 kg and 165.3+/-19.3 cm) performed five different exercise testing protocols at different speeds on a treadmill until exhaustion. Maximal effort treadmill (0.7% incline) testing protocols were performed using three timeframes. The first was focussing on short duration tests (S1 and S2) where incremental increases in velocity (0.42 and 0.1 m.s(-1)) were required from a stationary start. The second were medium duration tests (M1 and M2) where the athlete started at their 200 m and 800 m personal best time (mean velocities) and then had the velocity increased 1 km.h(-1) by every 10 and 60 s respectively. The long duration test (L) started at 14 km.h(-1) and velocity was increased by 2 km.h(-1) every 120 s. Maximal heart rate, maximal concentration of lactate, maximal speed, and maximal duration of the test were measured. RESULTS: The highest concentration of lactate and the highest heart rates were measured in the longest tests. CONCLUSION: During maximal effort testing wheelchair athletes are able to produce higher lactate concentrations when tested for longer duration. Post test lactate assessments provide little information in short duration testing protocols. Sequential lactate assessments post-test may provide additional information on the rate of recovery for middle distance wheelchair athletes and warrants further investigation.     

基因重组神经营养蛋白-3的生物学活性

目的：测定ＮＴ－３ｃＤＮＡ／ＣＨＯ细胞表达的基因重组ＮＴ－３的生物学活性。方法：体外培养８日龄鸡胚背根神经节（ＤＲＧ）,加入条件培养基,测量背根节神经突起生长的长度。结果：ＮＴ－３ｃＤＮＡ／ＣＨＯ细胞培养４８ｈ后的无血清条件培养基１：２４稀释后即能促进ＤＲＧ神经突破的生长;随着其中ＮＴ－３浓度增加,神经突破长度也逐渐延长,有明显的量效关系;ＤＲＧ培养４８ｈ长出的神经突破与２４ｈ相比,明显长而致密;     

Biventricular thrombus and associated myocardial infarction in a rheumatoid arthritis patient: a case report and literature review

Autoimmune diseases including rheumatoid arthritis have an increased incidence of cardiovascular disease. Rheumatoid arthritis (RA) confers a prothrombotic state and is associated with venous thrombosis, but its association with arterial thrombosis and embolism is not clear. In present report, we introduce a unique case of a 42-year-old woman with RA, who was admitted to the emergency service with back pain and diagnosed as having large right and left ventricular thrombus and myocardial infarction, associated with embolization of the thrombus. We also review the literature about RA and arterial and intraventricular thrombosis.     

6-取代苯基-3(2H)哒嗪酮的合成、抗惊活性及其构效关系的研究

本文报道了14个6-取代苯基-4,5-二氢-3(2H)哒嗪酮和15个6-取代苯基-3(2H)哒嚎酮的合成及其抗电惊活性。其ED50值表明,以2′,4′-二氯苯基-3(2H)哒嗪酮的抗惊作用为最强。构效分析表明,苯环上的取代基对化合物的抗惊活性有明显影响,吸电子取代基和疏水性参数值较大的取代基有利于提高化合物的抗惊活性。     

大鼠红细胞流变性变化及抗运动疲劳效应与补服肉碱和糖的作用

目的:观察单独和配合补充肉碱和糖对大鼠红细胞流变性及抗运动疲劳能力的影响。方法:实验于2005-09/11于河北师范大学体育学院运动生理学实验室完成。①选用SD雄性大鼠72只,按随机数字表法分为4组:安静组(n=6)、安静补服组(n=18)、安慰运动组(n=12)和补服运动组(n=36)。安静补服组和补服运动组均给予3种药物形式:左旋肉碱(由沈阳东宇精细化工有限公司生产)、葡萄糖(济南利民制药有限公司生产)、肉碱和葡萄糖。安静补服组和补服运动组每天上午8∶30给予自来水溶解的肉碱和/或糖补剂,安静组和安慰运动组给予相同量的自来水。连续补充7d,补服量:肉碱组、葡萄糖组、肉碱 葡萄糖组分别为650mg/(kg·d),7g/(kg·d),325mg/(kg·d) 3.5g/(kg·d)。②在实验第8天,将安静组取血4mL。安慰运动组和补服运动组进行无负重游泳至力竭,然后取血。采用北京泰诺德新技术研究所生产的BV-100型无摩擦式血液流变仪测全血高切黏度(180s-1)、全血高切还原黏度(180s-1)、全血低切黏度(3s-1)、全血低切还原黏度(3s-1)、刚性指数及聚集指数。③计量资料进行正态分布、方差齐性检验后,再进行方差分析。结果:大鼠72只均进入结果分析。①红细胞流变性指标变化:安静补服组各组虽大部分红细胞流变性指标有改善,但与安静组相比,差异无显著性意义(P>0.05)。安慰运动组运动后5min全血高切黏度和全血高切还原黏度明显高于安静组(P<0.01),运动24h后全血高、低切黏度和红细胞聚集指数明显高于安静组(P<0.01)。一次力竭运动后5min各补服运动组全血低切黏度明显低于安慰运动组(P<0.01)。各组间红细胞刚性指数和红细胞聚集指数差异不明显(P>0.05)。各补服运动组间相比,补服肉碱组的全血低切还原黏度最高(P<0.01)。各补服运动组运动后24h全血低切还原黏度和红细胞聚集指数明显低于安慰运动组(P<0.05～0.01),补服肉碱和肉碱 葡萄糖运动组全血低切还原黏度和全血低切黏度、红细胞聚集指数明显高于补服葡萄糖运动组(P<0.05～0.01)。②抗疲劳作用:补服肉碱、葡萄糖、肉碱 葡萄糖运动组大鼠游泳时间分别为(334.5±27.81),(321.0±51.83),(326.5±39.9)min,均长于安慰运动组[(252.5±42.69)min,P<0.01];各补服运动组间差异不明显(P>0.05)。结论:单独补充或合用肉碱和糖均有利于力竭运动后大鼠红细胞流变性指标的改善,导致其运动能力的提高。