A head-to-head comparison of measurement properties of the EQ-5D-3L and EQ-5D-5L in acute myeloid leukemia patients

Quality of Life Research - This study aimed to compare the measurement properties of EQ-5D-3L(3L) and EQ-5D-5L(5L) in patients with acute myeloid leukemia (AML) in China. We consecutively recruited...     

Post-translational modification of proteins by arginine and lysine following crush injury and during regeneration of rat sciatic nerves

Following crush injury to rat sciatic nerves, a crude fraction of the 150,000 g supernatant can post-translationally incorporate [3H]Arg and [3H]Lys into endogenous proteins in amounts approximately 10 times uninjured control nerves. These increases occur in the proximal nerve stump within 2 h of injury and 2 weeks later in a distal segment of nerve containing the tips of the regenerating axons. In the present experiments, the endogenous nerve proteins modified by Arg or Lys in these nerve segments have been identified using two-dimensional polyacrylamide gel electrophoresis. The fraction used to assay for protein modification, the void volume of a Sephacryl S-300 column, was found to contain only a few proteins visible by Coomassie blue staining, one of which is likely to be albumin (68 kDa, pI 6.4). While this protein was modified by both Arg and Lys, the majority of label was found in areas not showing Coomassie blue staining. This indicates that of the many potential targets of post-translational arginylation and lysylation, most are proteins of relatively low abundance. A variety of proteins were modified by Arg or Lys alone while others were modified by both Arg and Lys. A high molecular weight protein (175 kDa, pI 9.0) was modified only by Lys and only at 2 h post crush. Of a variety of modified proteins of approximately 17 kDa one (pI 6.3) was modified by both Arg and Lys and at both time points, while another (pI 9.0) was modified at both time points, but only by Lys. The results show that Arg and Lys can be added post-translationally to a large number of low abundance, soluble sciatic nerve proteins, and that some of those proteins are modified only by Arg or Lys while others are modified by both Arg and Lys. Also, the modification of certain proteins appears to be associated specifically with the immediate response of a nerve to injury (e.g. 88 kDa, pI 7.1) while others are associated with the regenerative period (e.g. 56 kDa, pI 7.4).     

Posttranslational modification of nerve proteins by amino acids

Both axonal and glial components of nerve are capable of carrying out reactions in which Arg, Lys, Leu, Pro, Val, AJa and Ser can be covalently linked to endogenous proteins in reactions which require tRNA but occur in the absence of ribosomes and ribosomal RNA. These posttranslational protein modifications appear to play important roles in nerve regeneration since they are increased more than 10-fold within 2 h of a crush injury in nerves which are capable of regeneration, but are not activated in nerves not capable of regrowth following injury. The regulation of the modification of proteins by Arg and Lys in vivo appears to be the function of separate peptides. The exogenous application of serine protease inhibitors (but not other protease inhibitors) mimics the effect of the endogenous peptides, suggesting that the endogenous regulators have serine protease inhibitory activity. The targets for modification are proteins of low abundance and thus far have been identified only in terms of their molecular weights and isoelectric points. The site of addition of Arg, but not the other amino acids, to target proteins is to the amino terminus. The addition of Arg to an amino terminus is likely to be involved in the ubiquitin mediated proteolysis of the modified protein. One of the most unusual findings in these series of experiments is that in regenerating sciatic nerves, amino acid modified proteins aggregate to form complexes of greater than 2 × 106 Da. The significance of this finding is not known. But we speculate that the aggregate may result from the assembly of an insoluble functional unit of the cell from soluble precursor proteins, and that the trigger for their assembly is amino acid modification.     

高位复杂性肛瘘的解剖学切除术

目的 探索治疗高位复杂性肛瘘较理想的手术方式。方法 应用解剖学原理,行瘘管切除、保留括约肌、内口缝合、创面开放术式,对高位复杂性肛瘘进行手术治疗。结果 45例一期治愈,1例二期治愈,无肛门失禁、肛门狭窄等并发症。结论 解剖学切除术是一种治疗高位复杂性肛瘘较理想的手术方式。     

99mTc-DTPA气溶胶显像测定呼吸道粘液纤毛清除功能

为进一步研究呼吸道疾病时的粘液纤毛清除功能,采用99mTc-DTPA气溶胶吸入显像,通过电影显示定性和定量指标分析.对18 例健康受试者和患者进行了显像研究,得到气道清除率和粘液纤毛清除率的正常值,并观察了32例慢性阻塞性肺病(COPD)患者气管-支气管纤毛清除功能的改变.结果显示,健康受试者与COPD患者粘液纤毛清除率(mm/min)分别为3.89±0.92和1.32±0.59,两者比较有显著性差异(P＜0.01),COPD患者不同时间气道清除率和粘液纤毛清除率均明显低于健康受试者(P＜0.01).本研究方法简便客观,具有定性观察和定量分析的优点,对于呼吸系统其它疾病(如支气管扩张、原发性纤毛无运动)的研究及药物疗效的评价具有重要的临床实用价值.     

重组人肝细胞生长因子基因的克隆

用ＲＴ－ＰＣＲ技术从人胎盘组织内成功地扩增全长肝细胞生长因子（ＨＧＦ）ｃＤＮＡ基因（２ １８４ｂｐ）,并将其克隆至ｐＧＥＭ－Ｔ载体,经限制性核酸内切酶ＮｄｅⅠ,ＢｇｌⅡ,ＨｉｎｄⅢ,ＢａｍＨⅠ和ＸｈｏⅠ的酶谱分析和ＤＮＡ测序分析证实。再将其亚克隆至逆病毒载体ｐＬＮＬ－ＸＨＣ,可进一步用于基因表达和基因治疗的研究。     

医古文求疵四则

古人用字行文,决非凭空虚构;遣词造句,十分精确.反复阅读,才能体味其中之妙.本义、引申,需谋全篇,方能准确理解.笔者不揣愚陋,就医古文规划教材的注释提出求疵四则,以便投石问路.