THE ROLE OF ACTIVE SODIUM AND POTASSIUM TRANSPORT IN HYPONATREMIC STATES IN INFANCY AND CHILDHOOD

ABSTRACT. Sigström, L. (Department of Paediatrics I, University of Goteborg, östra Sjukhuset, Göteborg, Sweden). The role of active sodium and potassium transport in hyponatremia states in infancy and childhood. Acta Psediatr Scand, 70:353, 1981.–Erythrocytes from 14 infants and children with serum sodium concentrations of 125 mmol/1 or less were analyzed for total and Na⁺, K⁺-ATPase, sodium and potassium content and ATP concentrations to evaluate the role of active Na⁺-K⁺ transport in hyponatremia. In six out of nine patients, with a duration of hyponatremia of more than 48 hours low Na⁺, K -ATPase activities and high erythrocyte sodium concentrations and Na⁺-K⁺ ratios were found indicating that a decreased Na⁺, K⁺-ATPase activity leading to an increased intracellular accumulation of sodium ions may have reduced the extracellular sodium concentration. Three subjects with large sodium losses had high Na⁺, K⁺-ATPase activities and normal erythrocyte sodium concentrations. In five cases of hyponatremia with a duration of less than 24 hours the variables indicating active Na⁺-K⁺ transport were normal. The therapeutic implications with sodium substitution and the use of drugs affecting active Na⁺-K⁺ transport are discussed.     

Evaluating fetomaternal hemorrhage by alphafetoprotein and Kleihauer following therapeutic abortions

In a survey of 75 patients at 6-11 weeks gestation, fetomaternal hemorrhage (FMH) was detected by significant rises (greater than 2 S.D.) in maternal alphafetoprotein (AFP) levels in 57% of patients, while increased fetal cells were detected by the Kleihauer test in 24% of patients. With increasing gestation, FMH was detected more readily by both tests; however, in evaluating FMH at less than 10 weeks gestation. AFP was found to be a more sensitive and reliable marker than the Kleihauer test. We suggest that there is a gray zone for the Kleihauer test in early gestation, when erythroblasts containing embryonic hemoglobins are gradually replaced in the fetal circulation by erythrocytes containing fetal hemoglobin.     

Autoimmunity in transfusion babesiosis: A spectrum of clinical presentations

Transfusion‐acquired babesiosis can be an asymptomatic or self‐limited febrile hemolytic illness in a healthy host. A persistent, relapsing, and/or fulminant course with the development of life‐threatening complications may be seen in immunocompromised or splenectomized patients. As in malaria, erythrocyte parasitemia is often associated with nonimmune hemolysis, and can be treated with erythrocytapheresis. Just as warm autoantibodies have been reported in malaria infection, the development of autoantibody‐mediated immune hemolysis has been reported in babesiosis. We treated a previously healthy male with multiple injuries from a motor vehicle accident necessitating massive transfusion. Late in the hospitalization, his blood smear revealed Babesia microti, confirmed by PCR study and serology. This was eventually traced to a unit of blood from an asymptomatic blood donor that was transfused during his initial trauma care. Specific antibiotic therapy was begun, and severe hemolysis from a high parasite burden required red blood cell exchange which led to rapid abatement of the hemolysis. He had a positive DAT (IgG with a pan‐reactive eluate) but no serum autoantibody. This persisted for 10 days following cessation of hemolysis, and became negative while still on antibiotics while his parasite burden became undetectable. Reports of autoimmunity associated with community acquired babesiosis often have severe hemolysis from their autoantibodies, but our case shows that autoantibodies may also follow transfusion‐acquired babesiosis. The nature of the autoantigen is unknown. J. Clin. Apheresis, 2010. © 2010 Wiley‐Liss, Inc.     

Comparative erythrocyte metabolism in three species of marsupials from Western Australia

A comparative study was carried out to investigate various aspects of erythrocyte metabolism in three species of marsupials located in the western part of Australia. The burrowing bettong (Bettongia lesueur) and the Barrow Island euro (Macropus robustus isabellinus) were captured on Barrow Island whereas the mainland euro (Macropus robustus erubescens) was captured from the Pilbara region of northwest Western Australia. Aspects of erythrocyte metabolism studied included: levels of glycolytic intermediates, enzyme activities, sensitivity of erythrocytes to oxidants and methaemoglobin reducing capacity. Some important findings were: (1) no relationship was observed between haemoglobin and diphosphoglycerate levels; (2) both species from Barrow Island had lower levels of catalase than the mainland species; and (3) methaemoglobin reductive capacity was greater in the erythrocytes of the burrowing bettong compared to the two species of euro.     

Red blood cell transfusions in newborn infants: Revised guidelines

In general, health care professionals taking care of high risk infants in neonatal intensive care units have become more restrictive in their use of red blood cell transfusion over the past 10 years. The present statement is intended for those caring for high risk newborn infants (preterm to one month of age). The objectives of this statement are to provide guidelines to reduce the incidence of anemia in preterm and term infants, to identify strategies to decrease the need for red blood cell transfusions and to limit donor exposure in this population. Recommendations for red blood cell transfusions are included.     

超氧化物歧化酶及过氧化氢酶对辐射所致红细胞溶血及脂类过氧化的影响

辐射所致红细胞溶血率不仅随照射剂量增加而增加,而且随放置时间的延长,溶血率也相应增加。加入牛红细胞超氧化物歧化酶或从牛肝中纯化的过氧化氢酶可使溶血率显著减少。辐射可使红细胞发生脂类过氧化,其脂类过氧化值随着照射剂量增加而增加。加入超氧化物歧化酶,对脂类过氧化的减轻作用不明显或很轻微,但加入过氧化氢酶却有较强的减轻脂类过氧化的效果,而且还观察到茜甙减轻脂类过氧化的效能类似维生素E。     

慢性阻塞性肺疾病急性加重期患者体液离子含量的变化

目的：了解慢性阻塞性肺疾病（COPD）患者体液离子含量的变化。方法：选择46例合并肺心病的COPD急性加重期患者，测定其血清、红细胞、白细胞及24h尿K、Na、Ca、Mg离子含量。结果：患者自细胞Ca增高，红细胞Ca、Mg、K及白细胞Mg、血清Mg、Na均显著降低。红细胞Mg与白细胞Mg显著正相关。该组患者尿Ca增多占54％，尿K、Na、Mg减低者分别占92％，65％及32％。结论：COPD患者存在K、Mg缺失，用红细胞Mg评价机体的Mg状态更具有实用性。     

异丙酚对急性和慢性代谢性酸中毒大鼠红细胞内pH的影响

目的 观察异丙酚对急性和慢性代谢性酸中毒大鼠红细胞内pH(pHi)的影响.方法 Wistar大鼠,雌雄不拘.第一部分采用静脉输注HCl的方法制备急性代谢性酸中毒模型,模型制备成功的40只大鼠随机分为4组(n=10):10%脂肪乳10 ml·kg·h-1组(F组)、碳酸酐酶(CA)抑制剂乙酰唑胺20 mg·kg·h-1组(Z组)、异丙酚10 mg·kg·h-1组(P1组)和异丙酚20 mg·kg·h-1组(P2组).第二部分采用管饲NH4Cl的方法制备慢性代谢性酸中毒模型,模型制备成功的40只大鼠随机分为4组(n=10),处理情况同第一部分.分别于给药前、给药1、3、6 h时采集动脉血样,测定红细胞pHi、CA活性及钠氢交换体-1(NHE-1)活性.结果 第一部分与F组比较,Z组CA活性降低(P<0.05或0.01),P1组和P2组pHi、CA活性及NHE-1活性差异无统计学意义(P>0.05).第二部分与F组比较,Z组、P1组和P2组pHi和CA活性降低(P<0.05或0.01);与Z组比较,P1组和P2组pHi和CA活性降低(P<0.05或0.01),NHE-1活性差异无统计学意义(P>0.05).结论 静脉输注异丙酚10、20 mg·kg-1·h-1可导致慢性代谢性酸中毒大鼠红细胞phi降低,其机制与抑制CA活性有关;而对急性代谢性酸中毒大鼠红细胞pHi无影响.     

精神分裂症患者血清、血浆、红细胞内氯氮平及其代谢物浓度的研究

目的　比较精神分裂症患者血清、血浆、红细胞内氯氮平及其代谢物浓度之间的关系。方法　对 5 9例精神分裂症患者氯氮平治疗 8周 ,以高效液相色谱法测定患者血清、血浆和红细胞内的氯氮平、去甲氯氮平和N 氧化物氯氮平浓度。结果　精神分裂症患者血清、血浆、红细胞之间的氯氮平及其代谢物浓度呈两两正相关。血清氯氮平、去甲氯氮平、N 氧化物氯氮平浓度分别比血浆低(11± 13) % ,(15± 17) % ,(2 2± 2 9) % ;红细胞内氯氮平、去甲氯氮平、N 氧化物氯氮平浓度分别为血浆浓度的 (2 7± 5 ) % ,(5 0± 10 ) % ,(2 8± 18) % ;血清、血浆、红细胞内去甲氯氮平 /氯氮平比值分别为(6 2± 17) % ,(6 4± 15 ) % ,(12 1± 2 3) % ,N 氧化物氯氮平 /去甲氯氮平比值分别为 (18± 11) % ,(18±8) % ,(17± 15 ) %。结论　在氯氮平的血药浓度监测中 ,测定血浆浓度可以减少误差 ;红细胞内浓度与血浆浓度相关良好 ,去甲氯氮平在红细胞内分布较多。