烧伤患者血浆和红细胞游离氨基酸变化及输注氨基酸对其变化的影响

动态测定烧伤患者血浆及红细胞内游离氨基酸的含量 ,探讨输入外源性氨基酸后对血及红细胞内游离氨基酸的影响。以日立 835— 5 0型氨基酸自动分析仪测定烧伤患者血浆及红细胞内游离氨基酸含量。结果发现烧伤患者血浆总游离氨基酸浓度从伤后到 2 1天均显著降低 (P <0 .0 5～ 0 .0 1) ;赖、苯丙和苯丙 酪氨酸比值显著升高 (P <0 .0 5～ 0 .0 1) ;色、组、精、丙、甘、苏、脯和丝氨酸比值显著降低 (P <0 .0 5～ 0 .0 1) ;缬、亮、异亮、酪、胱和支链氨基酸伤后早期降低。烧伤患者红细胞内总游离氨基酸含量不同程度降低 ,其中 1、3、7天降低显著 (P <0 .0 5～ 0 .0 1) ;红细胞内苯丙和苯丙 酪氨酸比值未见显著性升高 ;色、蛋、精、脯氨酸含量很低或基本未测出。输注复合氨基酸注射液后未能显著改善患者血及红细胞内游离氨基酸含量。结果提示烧伤患者红细胞内游离氨基酸含量的变化趋势与血浆游离氨基酸变化趋势基本一致 ;烧伤后红细胞内苯丙氨酸及苯丙 酪氨酸比值有别于血浆变化。本研究条件下补充外源性氨基酸未能显著改变烧伤患者血浆及红细胞内游离氨基酸的含量     

休克期切痂猪血浆氨基酸的变化

观察烧伤休克期切痂后猪血浆游离氨基酸的变化规律 ,探讨焦痂毒素对全血氨基酸浓度的影响。以日历83 5 5 0型氨基酸自动分析仪 ,测定TBSA3 5 %Ⅲ度实验用小型猪血浆游离氨基酸 ,同时分析相关指标 (血LPS、GPT和TNF)的变化 ,结果显示休克期切痂组血浆游离氨基酸 (除个别氨基酸的个别时间点有变化外 )无显著性变化 ;在伤后 6d和 1 0d苯丙氨酸显著降低 ,血LPS、GPT和TNF也较对照组低 ,提示焦痂的存在对肝脏代谢有一定的影响     

健康学龄前儿童血浆游离氨基酸含量研究

采用丹酰氯薄膜层析法分析了６５名３～７岁健康儿童血浆游离氨基酸含量。结果表明：血浆１１种游离氨基酸含量未见性别年龄差异,其正常值可供临床实践应用。血浆游离氨基酸在健康组中显著高于残疾组,提示重度营养不良时,各种氨基酸含量显著下降。     

某些内科系统疾病患者血浆游离氨基酸的变化及意义

为了解某些内科系统疾病的血氨基酸代谢特点。测定１７０例９种内科系统急慢性疾病患者血浆游离氨基酸浓度,并分别与５８例健康人血浆氨基酸浓度作对比分析。９种疾病的血浆胱氨基酸浓度不同程度升高,以尿毒症病人最为显著,炎症性病人血浆苯丙、蛋、赖氨酸和苯丙／酪比值显著升高,丙、组、精、脯氨酸和支／芳比值显著降低;糖尿病和甲亢病人血浆总游离氨基酸、谷、丙、酪、赖和支链氨酸显著升高;糠尿病病人支／芳比值显著升高,表明不同疾病的血氨基酸浓度有特征性变化,炎症是导致血氨基酸代谢紊乱的重要因素     

血浆中氨基酸检测技术探讨

在血浆中检测游离氨基酸含量是临床诊断的重要手段之一。本文讨论了液相色谱法、氨基酸分析法、液质联用技术等几种血浆中氨基酸的检测技术,并介绍这些技术在氨基酸检测中的应用,为建立血浆中游离氨基酸的分析方法提供参考依据。     

新型氨基酸制剂对创伤大鼠血游离氨基酸的影响

观察了富含牛磺酸 (Tau)、谷氨酰胺 (Gln)以及高支链氨基酸 (HBCAA)的新型氨基酸制剂对创伤大鼠血中游离氨基酸浓度的影响。结果表明 ,创伤后三天起 ,血浆游离氨基酸总和均显著降低 ,对照组基本无改变 ;创伤后Tau、BCAA、精氨酸以及天冬氨酸等具有抗氧化和免疫调节作用的氨基酸含量明显降低 ,新处方使用一周后其浓度有效回升 ,且效果好于 17种氨基酸 ,从而有利于机体伤口的愈合。这些结果为进一步阐明复合氨基酸制剂促进创伤愈合的作用及其开发应用提供了理论依据     

肺癌患者胸水游离氨基酸分析

本文对11例肺癌患者胸水13种游离氨基酸作了分析,并与28例正常人血浆游离氨基酸水平作了对照,结果表明:肺癌患者胸水的必需及非必需氨基酸普遍高于正常人血浆游离氨基酸,但其胸水谷氨酰胺水平则明显低于正常人血浆水平。     

实验动物血及组织游离氨基酸含量

本文报告实验动物血及组织游离氨基酸含量,结果表明,实验狗和Wistar大鼠血游离氨基酸含量比较恒定。实验兔组织游离氨基酸含量普遍高于血。     

保定市郊小学五年级儿童血中氨基酸水平研究

采用日立８３５－５０型氨基酸分析仪对河北保定市郊正常五年级小学生血浆游离氨基酸作了分析测定,所得结果与刘哲等人实验结果进行了比较,从而为了解市郊正常小学五年级儿童血浆游离氨基酸的正常值提供参考,这对于该时期儿童的营养调查及评价和临床代谢性紊乱疾病的辅助诊断,具有十分重要的意义。     

癫痫患者血浆中游离氨基酸水平分析

对７１例癫痫患者血浆中１８种游离氢基酸与３６例正常人血浆中游离氨基酸的水平对照。分析表明,抑制性氨基酸（γ－氨基丁酸、甘氨酸）水平明显升高的癫痫患者,其它氨基酸水平绝大多数低于正常人;兴奋性氨基酸（谷氨酸、天门冬氨酸、丙氨酸、谷氨酰胺）水平明显升高的癫痫患者,其它氨基酸水平低于正常人。     

不同病因的慢性肾病患者血清氨基酸谱存在显著差异

慢性肾病(chronic kidney disease, CKD)患者血清氨基酸谱发生了显著性变化,但目前并无不同病因的CKD患者血清氨基酸谱的比较研究。本研究主要探究不同病因CKD患者血清氨基酸谱的差异,以及差异氨基酸与肾疾病发生发展的相互关系。选取79例确诊慢性肾病的成年患者,根据其病因,分糖尿病肾病组、高血压肾病组及慢性肾小球肾炎组。另选取25例性别年龄匹配的健康成年人为正常对照组。收集及处理清晨空腹血清标本,采用反相高效液相色谱法（reverse-phase high-performance liquid chromatography, RP-HPLC）测定血清中22种游离氨基酸的水平。结果显示,与正常对照组相比,3组CKD患者血清赖氨酸、丝氨酸、甘氨酸、伽马氨基丁酸(GABA)、色氨酸、亮氨酸以及酪氨酸水平均显著下降（P<0.05）,而血氨水平显著升高（P<0.05）。糖尿病肾病组患者血清苏氨酸水平明显高于其余3组（P<0.05）,而血清天冬氨酸水平显著低于其余3组（P<0.05）。慢性肾小球肾炎患者血清异亮氨酸水平显著低于糖尿病肾病及高血压肾病患者（P<0.05）。上述结果证实,慢性肾病患者血清氨基酸谱较正常对照发生显著变化,且不同病因CKD患者部分血清氨基酸水平存在显著差异。其中,色氨酸水平的差异可能是不同病因CKD患者肾功能恶化速度不一致的原因之一。     

Bile acids of patients with renal failure receiving chronic hemodialysis

Bile acids in serum, urine and dialysate of 8 patients with renal failure in chronic hemodialysis were analyzed by gas chromatography and gas chromatography-mass spectrometry. The following results were obtained: 1. Lithocholic acid, 3 beta-hydroxy-5-cholen-24-oic acid, deoxycholic acid, chenodeoxycholic acid, ursodeoxycholic acid, and cholic acid were identified in hemodialysate as well as in serum and urine. 2. The serum bile acid concentration of the patients was 2.78 +/- 0.57 micrograms/mL before hemodialysis and 1.34 +/- 0.48 micrograms/mL after a 5-h period hemodialysis with cuprophane membrane. The proportions of secondary bile acids in predialysis and postdialysis serum of patients were significantly higher than those of healthy subjects. 3. Two out of 8 patients excreted urine. But the amounts of bile acids in urine of the patients were very small compared to those of healthy subjects. 4. The amount of bile acids removed from blood by hemodialysis was 0.70 +/- 0.25 mg. In dialysate, cholic acid constituted a larger proportion of the total bile acids, and lithocholic acid a smaller proportion, when compared to those in urine of patients and healthy subjects.     

Amino Acid Neurotransmitters in Nucleus Tractus Solitarius: An In Vivo Microdialysis Study

Amino acid neurotransmitters in the nucleus tractus solitarius (NTS) are thought to play a key role in the mediation of visceral reflexes and glutamate has been proposed as the neurotransmitter of visceral afferent nerves projecting to this region. The present studies sought to characterize the use of in vivo microdialysis to examine extracellular fluid levels of amino acids in the NTS of anesthetized rats. Using a microdialysis probe that was 450 μm in length and a sensitive HPLC assay for amino acids, amino acids could be measured in dialysate samples collected from the NTS. Perfusion of the microdialysis probe with 60 mM K^±, to elicit depolarization of nerve terminals in the vicinity of the probe, resulted in increased dialysate fluid levels of aspartate, glutamate, glycine, taurine, and GABA. In contrast, glutamine and tyrosine were decreased and other amino acids were not significantly affected. Prior removal of the ipsilateral nodose ganglion did not alter the K^±-evoked changes in dialysate levels of any of these amino acids. Electrical stimulation of the vagus nerves, using a variety of stimulus parameters, did not significantly alter dialysate levels of glutamate or any of the other amino acids that were measured. Blockade of glutamate uptake with dihydrokainate increased dialysate levels of glutamate, aspartate, and GABA, but in the presence of dihydrokainate vagal stimulation did not alter dialysate levels of these amino acids. The results show that in vivo microdialysis can be used to examine amino acid efflux in the rat NTS and provide further evidence for amino acidergic neural transmission in the NTS. However, these studies fail to support the hypothesis that vagal afferents release glutamate or aspartate.     

低智儿童与正常儿童中氨基酸的比较研究

我们对 30例低智儿童血清中TAU ,SER ,GLU ,GLY ,ALA ,VAL ,CYS ,MET ,ILE ,LEU ,TYR ,PHE ,TRP ,HIS ,ORN ,LYS ,ARG ,PRO ,18种游离氨基酸进行了测定。研究结果显示 :患儿血清中 11种游离氨基酸降低分别为 :TAU ,SER ,VAL ,MET ,ILE ,LEU ,TRY ,PHE ,ORN ,LYS ,TRP .氨基酸的失衡 ,儿童的蛋白质合成就将会受到严重的影响 ,因此将导致大脑的分化 ,发育受阻 ,引起智力低下。     

Biochemical Studies on Hydrocyanic Acid Potential and Amino Acid in Sorghums

This research is conducted to study the HCN-p of several types of sorghum, as well as their changes in amino acid. The HCN-p of sorghum seedling reached its maximum in 4–6 days after germination. It was found that the first leaf of the seedling has the highest HCN-p. Among the 14 varieties studied, Atlas had the highest HCN-p (1984ppm), whereas NP-22 had the lowest value (479ppm). Light-grown seedlings had higher HCN-p. There was no obvious difference in protein amino acid in sorghum seedlings with .different HCN-p. However, the free amino acid content did vary in the sorghum varieties. The content of free tyrval, pheleu and ileu in etiolated Atlas seedlings was significantly higher than that in NP-22 seedlings. However, under condition of light, the five free amino acids lowers significantly in content in Atlas when compared be NP-22. This proves that Atlas had a more sensitive enzyme system and under presence of light, its free amino acid content was rapidly converted to cyanide.     

Amino Acid Changes in a Genetic Strain of Epileptic Beagle Dogs

A neurochemical evaluation of beagle dogs with naturally occurring spontaneous generalized convulsive seizures was performed. Amino acid profiles of serum, cerebrospinal fluid (CSF), and biopsied cerebral cortex from epileptic dogs were compared with those from seizure-free siblings. No differences in absolute levels were noted. However, when levels were normalized as a percent of total free amino acids, seizures was performed. Amino acid profiles of serum, cerebrospinal fluid (CEF), and biopsied cerebral cortex from epileptic dogs were compared with those seizure-free siblings. No differences also the two groups differed in certain respects. Ten significant correlations between amino acid pairs appeared in epileptic dogs, but only one was seen in seizure-free animals. Seven of these ten correlations involved glutamate or taurine. It was noted that the highly correlated amino acids (taurine, glutamate, glycine, glutamine, alanine) all utilize sodium-dependent membrane transport processes. The sum of glutamate, aspartate, and glycine levels (competing sodium-dependent high-affinity systems) was significantly lower in epileptic beagles. Since this difference was noted in serum but not CSF or brain, it may indicate a diminished capacity of sodium-dependent high-affinity renal transport for acidic and certain small neutral amino acids.     

Effects of a Honeybee Sting on the Serum Free Amino Acid Profile in Humans

The aim of this study was to assess the response to a honeybee venom by analyzing serum levels of 34 free amino acids. Another goal of this study was to apply complex analytic-bioinformatic-clinical strategy based on up-to-date achievements of mass spectrometry in metabolomic profiling. The amino acid profiles were determined using hybrid triple quadrupole/linear ion trap mass spectrometer coupled with a liquid chromatography instrument. Serum samples were collected from 27 beekeepers within 3 hours after they were stung and after a minimum of 6 weeks following the last sting. The differences in amino acid profiles were evaluated using MetaboAnalyst and ROCCET web portals. Chemometric tests showed statistically significant differences in the levels of L-glutamine (Gln), L-glutamic acid (Glu), L-methionine (Met) and 3-methyl-L-histidine (3MHis) between the two analyzed groups of serum samples. Gln and Glu appeared to be the most important metabolites for distinguishing the beekeepers tested shortly after a bee sting from those tested at least 6 weeks later. The role of some amino acids in the response of an organism to the honeybee sting was also discussed. This study indicated that proposed methodology may allow to identify the individuals just after the sting and those who were stung at least 6 weeks earlier. The results we obtained will contribute to better understanding of the human body response to the honeybee sting.