一种新型18°×4扇形网织红细胞计数窥盘

目的研制一种新型18°×4扇形网织红细胞计数窥盘。方法使用安瓿刀在玻片上刻制,再与国际血液学标准化委员会(ICSH)推荐的Miller窥盘进行网织红细胞对比分析。结果新型网织红细胞计数窥盘和ICSH推荐的Miller窥盘的准确度是一致的,但新型网织红细胞计数窥盘的精密度显著优于ICSH推荐的Miller窥盘。其参考范围也与其他报道一致。结论新型网织红细胞计数窥盘做法简单,不需特殊设备,值得推广应用。     

Energy-dependent extrusion of cyclic 3′,5′-adenosine-monophosphate

Summary In reticulocyte-rich suspensions of red blood cells from rats extrusion of cAMP as a regulatory mechanism of intracellular cAMP was investigated.In response to isoprenaline and/or the phosphodiesterase inhibitors Ro 20-1724 and rolipram extrusion of cAMP increases dependent on the concentration of the drugs and time of exposure. However, these drugs exert their effects on the extrusion of cAMP only indirectly, i.e. via increased intracellular levels of cAMP, since the respective EC₅₀-values of the drugs for intracellular accumulation and extrusion of cAMP are identical (isoprenaline: 50 nM; rolipram: 1 M; Ro 20-1724: 15 M).The dependence of the rate of extrusion on intracellular levels of cAMP is characterized by a typical concentration-effect relationship from which a maximal capacity of cAMP extrusion of 3–6 nmol/10 min/10⁹ cells and a half maximal effective intracellular cAMP concentration of 40–50 nmol/10⁹ cells can be derived. This relationship has been inferred from either kinetic or steady-state approaches. At rapidly changing intracellular levels of cAMP an apparent time lag of extracellular cAMP accumulation is obligatorily conditioned by this relationship. Vasodilating drugs which lower the ATP content of the cells as well as the uncoupler of oxidative phosphorylation, FCCP, inhibit the extrusive process (papaverine > FCCP > dipyridamole > dilazep hexobendine carbocromene) leading to a 3–5-fold increase of the intrato extracellular concentration gradient of cAMP.It is concluded that extrusion of cAMP is a saturable and energy-dependent process which regulates the intracellular cAMP concentration independent of the activities of adenylate cyclase and phosphodiesterase.This work was supported by a grant from the Deutsche Forschungsgemeinschaft     

Utility of flow cytometric reticulocyte quantification as a predictor of engraftment in autologous bone marrow transplantation

Flow cytometric reticulocyte quantification with thiazole orange (TO) was used to study erythropoiesis in 20 patients following autologous bone marrow transplantation for the treatment of acute myelogenous leukemia. Flow cytometric reticulocyte analysis provided not only the reticulocyte percentage and absolute reticulocyte count but a quantitative reticulocyte maturity index (RMI) proportional to the amount of RNA in the reticulocytes. The RMI values, but not the reticulocyte percentage or absolute counts, correlated temporally with the rise in the absolute neutrophil counts in the posttransplantation period. In the majority of patients (12/20), the RMI value was the earliest indicator of bone marrow engraftment. The findings of this study demonstrate an important clinical utility of TO reticulocyte analysis by flow cytometry and indicate the diagnostic importance of the RMI measurement in the evaluation of erythropoietic activity in bone marrow transplant patients.     

基于倾向匹配法鉴别MCV和网织红细胞参数对地中海贫血和缺铁性贫血的价值

目的 探讨MCV(平均红细胞体积)和网织红细胞参数对地中海贫血和缺铁性贫血鉴别诊断的意义。方法回顾性收集2017年7月～2019年7月诊断为缺铁性贫血和地中海贫血的病例,依据诊断分为缺铁组(n=226)和地贫组(n=60)。采用倾向匹配法筛选基线资料,最终两组各纳入42例。比较两组MCV和网织红细胞参数。结果匹配后两组基线资料无显著性差异(P0.05),匹配前MCV两组间比较有差异(P0.05),匹配后没差异,匹配前后LFR/MFR/HFR(低荧光强度网织红细胞比率/中荧光强度网织红细胞比率/高荧光强度网织红细胞比率)在两组间比较均无差异(P0.05),Ret-He(网织红细胞血红蛋白)在匹配前后两组间比较,差异有统计学意义(P0.05)。结论 Ret-He对地中海贫血和缺铁性贫血鉴别诊断有一定的意义。     

Reticulocyte Hemoglobin Equivalent (Ret-He) Combined with Red Blood Cell Distribution Width Has a Differentially Diagnostic Value for Thalassemias

Abstract

As a type of congenital microcytic hypochromic anemia, thalassemia trait is often confused with other conditions, such as congenital sideroblastic anemia (CSA) and iron deficiency anemia, before a specific work-up is performed. However, these tests, including hemoglobin (Hb) electrophoresis, gene mutations and Prussian blue staining after bone marrow aspirate, are relatively expensive, time-consuming and invasive. To find labor-saving parameters to facilitate differential diagnosis, we retrospectively analyzed the routine blood indexes of 59 thalassemia trait cases [22 α-thalassemia (α-thal), 36 β-thalassemia (β-thal) and one α/β-thal], 21 CSA patients, and 238 iron deficiency anemia controls. Significantly higher reticulocyte Hb equivalent (Ret-He) and lower red blood cell (RBC) distribution width (RDW) were prominent in thalassemia trait. Furthermore, RDW-standard deviation (SD) was independent of the severity of anemia in thalassemia trait, similar to Ret-He in CSA. In the context of the same grades of anemia, Ret-He combined with RDW was powerful in differentiation of thalassemia from CSA and iron deficiency anemia. By receiver operation curve (ROC) analysis, Ret-He had a specificity of 67.06% and a sensitivity of 76.92% with a cutoff value of 20.9?pg for thalassemia trait in mild anemia and a specificity of 84.09% and a sensitivity of 68.42% with a cutoff value of 19.1?pg for thalassemia trait in moderate anemia. Regarding CSA, Ret-He had 92.94% specificity and 60.00% sensitivity in mild anemia, with a cutoff value of 18.1?pg. Overall, Ret-He and RDW are two convenient indexes able to differentiate thalassemia from the other two microcytic anemias, CSA and iron deficiency anemia.     

GCK-MODY diabetes as a protein misfolding disease: The mutation R275C promotes protein misfolding,self-association and cellular degradation

GCK-MODY, dominantly inherited mild hyperglycemia, is associated with more than 600 mutations in the glucokinase gene. Different molecular mechanisms have been shown to explain GCK-MODY. Here, we report a Pakistani family harboring the glucokinase mutation c.823C > T (p.R275C). The recombinant and in cellulo expressed mutant pancreatic enzyme revealed slightly increased enzyme activity (k_cat) and normal affinity for α-D-glucose, and resistance to limited proteolysis by trypsin comparable with wild-type. When stably expressed in HEK293 cells and MIN6 β-cells (at different levels), the mutant protein appeared misfolded and unstable with a propensity to form dimers and aggregates. Its degradation rate was increased, involving the lysosomal and proteasomal quality control systems. On mutation, a hydrogen bond between the R275 side-chain and the carbonyl oxygen of D267 is broken, destabilizing the F260-L271 loop structure and the protein. This promotes the formation of dimers/aggregates and suggests that an increased cellular degradation is the molecular mechanism by which R275C causes GCK-MODY.     

Twin anemia‐polycythemia sequence with suspected cardiac dysfunction

We present a case of twin anemia‐polycythemia sequence diagnosed postnatally with suspected chronic stress on the heart in the donor twin.     

网织红细胞血红蛋白含量在小儿营养性缺铁性贫血筛查中的价值

目的 探讨网织红细胞血红蛋白含量(CHr)对小儿缺铁性贫血(IDA)的筛查诊断效率.方法 检测分析39例IDA患儿,22例非IDA患儿,20例健康对照者外周血红细胞参数及铁代谢指标.结果 IDA组CHr、平均红细胞容积、平均红细胞血红蛋白含量、平均红细胞血红蛋白浓度、血清铁、血清总铁结合力及血清铁蛋白均值较健康对照组及非IDA贫血组明显降低(P<0.05),当临界值为28 pg时,CHr诊断IDA的灵敏度和特异性分别为90%和81%.结论 CHr优于传统的红细胞参数及铁代谢指标,可准确地诊断铁缺乏和缺铁性贫血,为1项简便、快速、价廉,可广泛用于铁缺乏的筛查.     

RBC、Ret-He与HbA2联合检测对地中海贫血的临床价值

目的:探讨小细胞或低色素人群中Ret-He和RBC在地中海贫血中的分布情况及联合HbA2对地中海贫血检测的价值。方法:选取本院2018年5月-2019年12月门诊检测出或住院的小细胞或低色素患者145例,将其分为地贫组(68例)及非地贫组(77例),并同时按贫血程度将患者分为非贫血、轻度贫血、中度贫血及重度贫血共4组,对患者进行Ret-He、RBC、RDW-CV及HbA2检测,比较各项参数的分布情况,并分析RBC、Ret-He与HbA2联合检测以辅助诊断地中海贫血的灵敏度特异度。结果:在小细胞或低色素患者中,根据贫血程度分级,Ret-He从非贫血组至重度贫血组逐渐下降(P<0.05);而RDW-CV则从轻度贫血组至重度贫血组逐渐上升(P<0.05);RBC及Ret-He在地贫组患者中均较非地贫组明显升高(P<0.05),而RDW-CV则在地贫组中较非地贫组明显降低(P<0.05);同时Ret-He在α-地贫中较β-地贫明显升高(P<0.05)。进行ROC曲线分析,Ret-He以19.25 pg为截断值,RBC以4.95×10^12/L为截断值时,联合HbA2,特异度为93.51%,灵敏度为66.18%,阳性预测值为90%,阴性预测值为75.189%。结论:在小细胞或低色素患者中,RBC、Ret-He及RDW-CV在地贫组及非地贫组的分布存在差异,并受贫血程度影响。加入Ret-He及RBC可提高小细胞或低色素患者依靠HbA2进行地中海贫血初筛时的特异度。     

网织红细胞血红蛋白含量在筛查女性铁缺乏中的应用

目的 探讨网织红细胞血红蛋白含量(CHr)在筛查女性铁缺乏中的应用.方法 选取体检中心506例女性体检者作为研究对象分为:铁缺乏组(无贫血缺铁组与缺铁性贫血组112例)与对照组(394例).检测红细胞计数(RBC)、血红蛋白(HGB)、红细胞压积(HCT)、红细胞分布宽度(RDW)、血清铁蛋白(SF)、血清铁(SI)及CHr等指标.结果 铁缺乏组CHr为(27.2±3.0)pg明显低于对照组的(30.6±l.3)pg,(P＜0.001).ROC曲线证实诊断女性铁缺乏CHr的曲线下面积为0.841,明显高于RBC、HGB、HCT、MCV、MCH、MCHC和RDW等指标(P＜0.05).结论 CHr可以用于女性铁缺乏的筛查及早期诊断.