预防性静滴钾离子、镁离子对急性心梗后并发室性心律失常的预防作用

目的 探究预防性静滴钾离子、镁离子对急性心梗后并发室性心律失常的预防作用。方法 选择2015年1月-2018年1月于西宁市第一人民医院进行治疗的78例急性心肌梗死患者为研究对象，按照随机数字表法将其均分为观察组与对照组，每组各39例患者。对照组患者进行常规急性心梗治疗，观察组患者在对照组基础上加用门冬氨酸钾镁进行治疗，对比两组治疗有效率，对比两组治疗前后血液流变学指标纤维蛋白原（Fib）、凝血酶原时间（PT）、血小板计数（Plt），对比两组治疗期间不良反应发生率及心律失常发生率。结果 治疗后，观察组患者治疗有效率为87.18%，对照组为76.92%，两组对比差异具有统计学意义（P<0.05）。治疗前两组患者Fib、PT以及Plt水平对比差异不具有统计学意义；治疗后，两组患者Plt及Fib水平低于治疗前，PT水平高于治疗前，差异有统计学意义（P<0.05）；治疗后观察组患者Plt及Fib水平低于对照组，PT水平高于对照组（P<0.05）。观察组患者不良反应发生率稍高于对照组，但对比差异不具有统计学意义。观察组心律失常发生率为7.69%，对照组为15.38%，两组对比差异具有统计学意义（P<0.05）。结论 预防性静滴钾离子与镁离子能够显著降低急性心梗患者心律失常发生率，同时有利于提高治疗有效率，改善其血流变指标，且安全性较高。     

硫酸镁、硝苯地平和酚妥拉明治疗妊高症

目的探讨对妊娠高血压综合征患者给予硫酸镁联合硝苯地平以及酚妥拉明治疗的临床效果。方法抽取医院在2018年2月-2019年2月所接收的156例妊娠高血压综合征患者,将其按照数字随机表的方法分为单纯组和联合组,每组分别为78例。单纯组给予单纯的硫酸镁进行治疗,联合组在单纯组给予硝苯地平以及酚妥拉明进行联合治疗,比较患者的治疗效果。结果联合组的治疗有效率显著高于单纯组,治疗前血压水平差异无统计学意义(P>0.05),治疗后联合组的收缩压和舒张压水平均低于单纯组,P<0.05,两组差异有统计学意义。结论对妊娠高血压综合征患者给予硫酸镁联合硝苯地平和酚妥拉明进行联合治疗,有效改善患者的血压水平。     

Effect of buffering on pharmacokinetics of ketoprofen enantiomers in man

Aims Concomitant administration of magnesium hydroxide may affect the rate or extent of absorption of non-steroidal anti-inflammatory drugs. In order to find out whether or not buffering modifies the pharmacokinetics of ketoprofen, plasma concentration-time courses resulting from oral administration of unbuffered formulations were compared with those of buffered formulations.
Methods Two groups of 12 healthy and young male subjects were included in two randomized cross-over studies and received single oral doses of ketoprofen 12.5 or 25  mg, respectively, given as tablets which were either unbuffered or buffered with magnesium hydroxide/citrate. Ketoprofen enantiomers in plasma were determined by h.p.l.c. up to 24  h post-dose.
Results Maximum plasma concentrations ( C _max ) of both the (R)- and (S)-enantiomer, observed after administration of the buffered formulations (12.5 and 25  mg), were higher compared with the unbuffered tablets by about 50–80%. The area under concentration-time data (AUC) was unaffected, and, hence, C _max/AUC was increased by buffering. Time to C _max ( t _max ) and mean residence time (MRT) tended to be or was shortened by buffering.
Conclusions It is concluded that buffering of two ketoprofen formulations with magnesium hydroxide/citrate enhanced the concentration maximum by increasing the rate of absorption and leaving AUC unaffected.     

三磷酸腺苷-氯化镁冷稀释血停搏液的实验研究及临床应用

用液体闪烁计数法测定离体再灌注兔心肌线粒体内４５Ｃａ２＋的放射性强度．观察三磷酸腺苷－氯化镁冷稀释血停搏液和冷稀释血停搏液对缺血再灌注兔心肌线粒体内４５Ｃａ２＋的影响．结果表明，在３０ｍｉｎ以内使用冷稀释血停搏液组兔心肌线粒体内４５Ｃａ２＋放射性强度高于三磷酸腺苷－氯化镁冷稀释血停搏液组（Ｐ＜０．０５），而６０ｍｉｎ时冷稀释血停搏液组的放射性强度稍高或接近于三磷酸腺苷－氯化镁冷稀释血停搏液组，差异无显著性（Ｐ＞０．０５）．在２７例心内直视手术中使用三磷酸腺苷－氯化镁冷稀释血停搏液均获良好效果．     

Inadequate dietary magnesium intake increases atherosclerotic plaque development in rabbits

Epidemiological studies have shown dietary magnesium (Mg) intake and serum Mg levels to be inversely correlated with the development of atherosclerosis. We hypothesized that low levels of Mg would promote atherosclerotic plaque development in rabbits. New Zealand white rabbits (4 months old, n = 22) were fed an atherogenic diet containing 0.12% (−Mg), 0.27% (control), or 0.43% (+Mg) Mg for 8 weeks. Blood samples were obtained at baseline, 2, 4, 6, and 8 weeks and were assayed for total cholesterol, high-density lipoprotein (HDL), non-HDL, triglycerides (TG), C-reactive protein, serum Mg, and erythrocyte Mg. Aortas from −Mg had significantly more plaque, with an intima thickness 42% greater than control and 36% greater than +Mg. Serum cholesterol levels rose over time, and at 8 weeks, −Mg had the highest and +Mg the lowest total and non-HDL cholesterol and TG levels, although these results did not reach significance. Over time, serum Mg levels increased, and erythrocyte Mg levels decreased. C-reactive protein significantly increased in all groups at 4 and 6 weeks but returned to baseline levels by 8 weeks. This study supports the hypothesis that inadequate intake of Mg results in an increase in atherosclerotic plaque development in rabbits.     

Neurotoxicity after spinal anaesthesia induced by serial intrathecal injections of magnesium sulphate An experimental study in a rat model

We have previously demonstrated in a rat model that the lumbar intrathecal injection of 0.02 ml 6.3% magnesium sulphate, a concentration iso-osmolar with rat plasma, produces a state of spinal anaesthesia and general sedation which reversed completely after 6 h, without evidence of neurotoxicity, immediately or during the week thereafter. Using the same model and five groups of six animals in each, we administered the same volume and concentration of magnesium sulphate and compared its clinical effects with those of 0.02 ml 12.6% magnesium sulphate, 0.02 ml 2% lignocaine and 0.02 ml 0.9% sodium chloride solution, given as a series of 15 injections on alternate days for a period of 1 month. The animals were then killed and their spinal cords and meninges examined histologically. No significant differences were noted in the times of onset, durations of sensory and motor blockade and the times to full recovery throughout the entire period of 1 month's observation in the animals receiving intrathecal 6.3% magnesium sulphate. In the group receiving 12.6% magnesium sulphate, the time of onset of sensory and motor blockade was shorter and the duration of both parameters was significantly longer than in the former group. Full clinical recovery and resumption of normal eating and drinking took place in both groups throughout the entire series of 15 successive intrathecal injections. Identical, mild, uniform histopathological changes in the spinal cord were seen in all the five groups, including the group in which only the intrathecal catheter was implanted. The complete recovery and benign consequences of repeated intrathecal injections of iso-osmolar magnesium sulphate in a rat model indicate a lack of neurotoxicity and provide an impetus for further trials in larger animal species, before initial clinical trials of this substance, given intrathecally, in humans.     

Zinc and magnesium in liver cirrhosis

Abstract. The Authors determined zinc (Zn) and magnesium (Mg) in the plasma, urine, erythrocytes (RBCs), mono- and polymorphonuclear cells (MNCs and PMNs) of patients with overt alcoholic and nonalcoholic liver cirrhosis. In order to obtain a clearer clinical picture, biochemical and nutritional parameters (retinol, tocopherol, six different carotenoids, creatinine-height index and tricipital skinfold), as well as markers of portal hypertension (spleno-portal size and platelet count) were also evaluated.
The plasma levels of Zn and Mg were found to be reduced, as were the urine levels of Mg. Urine Zn, on the other hand, was higher than normal. Plasma Zn correlated inversely, and urine Zn directly, with the severity of the disease, rather than with alcohol consumption or treatment with diuretics. Protein metabolism impairment would appear to affect the plasma transport of Zn rather than its overall availability in the organism; the opposite was found in the case of Mg, the availability of which appeared to be reduced. Determination of the two elements in RBCs, MNCs and PMNs suggested that a true nutritional deficit cannot be demonstrated. MNCs, rather than RBCs or PMNs seem better to reflect tissue status of trace elements.     

ATP-Mg~(2+)对缺血缺氧心肌保护作用的实验研究

用离体大鼠心脏灌流方法观察了ATP-Mg~(2+)等对缺血缺氧心脏再灌注后心功能的影响及超微结构变化。结果表明,ATP-Mg~(2+)对缺血缺氧心肌具有明显的保护效果,其作用与ATP-MgCl_2几乎相同;两者均优于单纯性ATP(ATP-2Na)。作者认为,ATP-Mg~(2+)是ATP-MgCl_2,心肌保护的有效成分。     

ACUTE EFFECT OF ETHANOL ON RENAL ELECTROLYTE TRANSPORT IN THE RAT

1. Despite human and animal studies, the direct effect of ethanol on renal water and electrolyte transport is poorly understood. The acute effect of increasing plasma concentrations of ethanol was evaluated in a water diuretic anaesthetized rat model which inhibits endogenous arginine vaso-pressin (AVP) release. 2. Ethanol at a plasma concentration of 1.69 ±0.28 mmol/L produced an immediate increase in urine flow (174 ± 11 μL/min pre-ethanol and 189 ± 13 and then 206 ± 12 μL/min during the ethanol infusion; P<0.001) as well as an increase in fractional sodium excretion (0.17 ± 0.04 to 0.28 ± 0.05 and 0.27 ± 0.05%; P<0.001). There was also a brief phosphaturia. These increases in electrolyte excretion had returned to control values by 20 min despite a further increase in the plasma ethanol concentration. 3. The urinary excretion of potassium, calcium and magnesium was not altered nor was glomerular filtration rate or renal plasma flow. 4. Ethanol at a mean concentration of 1.60 mmol/L did not alter the action of a maximal concentration of AVP (75 ng/kg) on water or electrolyte transport. However, the antidiuretic effect of a submaximal concentration of AVP (7.5 ng/kg) was augmented by ethanol at concentrations of 1.63 and 0.98 mmol/L. 5. These studies suggest that the ethanol induced diuresis commonly ascribed to inhibition of AVP secretion may also be due to other intrarenal effects of ethanol, possibly acting within the proximal tubule. These results also confirm recent in vitro findings that while ethanol does not inhibit the action of a maximal concentration of AVP, it does modulate the effects of lower AVP concentrations.