Thalassemia Gene Detection Results and Application Value of Hematological Indexes Among Pregnant Women in Xindu District of Chengdu City / 中国实验血液学杂志

OBJECTIVE@#To analyze the genotype characteristics of α- and β-thalassemia and the diagnostic value of hematological indexes in pregnant women in Xindu District of Chengdu.@*METHODS@#The blood routine parameters(MCV) <80 fl and (or) (MCH) <27 pg and hemoglobin electrophoresis were used to screen the pregnant women, PCR-reverse dot blot hybridization(PCR-RDB) technique was used to detect the common α- and β-thalassemia gene types in the primary screening positive population. The husbands of the diagnosed pregnant women were recalled for gene testing, and the highly suspected patients were checked by gene sequencing.@*RESULTS@#Among the 7 049 pregnant women, 1 740(24.68%) cases were positive for primary screening. 180 patients were diagnosed as thalassemia gene positive, among them, 94 cases (52.22%) of α-thalassemia were detected and six genotypes were found, in which --SEA /αα genotype was the highest (58 cases, 61.70%); 82 cases (45.56%) of β-thalassemia were detected and ten genotypes were found while CD41-42/N and CD17/N genotypes were the most common; there were 4 cases(2.22%) with α combined with β-thalassemia. Through clinical follow-up survey, there were 4 couples with the same type of thalassemia, one of them was induced labor after diagnosis of hemoglobin H disease. Receiver operating curve (ROC curve) was used to analyze the diagnostic value of hematological parameters in thalassemia positive pregnant women. The results showed that AUC(HBA2)<AUC(MCHC)<AUC(RDW-SD)<AUC(MCH)<AUC(MCV) (P<0.01).@*CONCLUSION@#The most common genotypes of α- and β-thalassemia in pregnant women in Xindu District of Chengdu were --SEA /αα, CD41-42/N, CD17/N. The blood routine indicators (HBA2、RDW-SD、MCHC、MCH、MCV) have high diagnostic value for screening of thalassemia.

Preliminary Study on Screening and Identification of Lewis a Antigen Mimic Epitope in Alpaca Phage Display Nanobody Library / 中国实验血液学杂志

OBJECTIVE@#To establish a new method for synthesizing Lewis blood group antigens, that is, the mimotopes of Lewis blood group antigens were screened by using an alpaca phage display nanobody library.@*METHODS@#We selected mimotopes of the Lewis a (lea) antigen by affinity panning of an alpaca phage display nanobody library using a monoclonal anti-lea antibody. Enzyme-linked immunosorbent assay (ELISA) was used to test the affinity of the positive clones for the monoclonal anti-lea antibody, and the high-affinity positive clones were selected for sequencing and synthesis. Finally, the sensitivity, specificity and reactivity of the synthesized lea mimotope in clinical samples were verified by ELISA.@*RESULTS@#A total of 96 phage clones were randomly selected, and 24 were positive. Fourteen positive clones with the highest affinity were selected for sequencing. The result showed that there were 5 different sequences, among which 3 sequences with the highest frequency, largest difference and highest affinity were selected for expression and synthesis. The sensitivity and specificity of lea mimic antigen by ELISA showed that, the minimum detection limit of gel microcolumn assay (GMA) and ELISA method were 25 times different, and the lea mimic antigen had no cross reacted with the other five unrelated monoclonal antibodies(P<0.001). Finally, 30 clinical plasma samples were analyzed. The mean absorbance of the 15 positive plasma samples was significantly higher than that of the 15 negative plasma samples (P=0.02). However, the positive signal values of the clinical samples were much lower than those of the monoclonal antibodies.@*CONCLUSION@#A new method of screening lea mimic antigen by using alpaca phage nanoantibody library has been established, which is expected to realize the screening of lea mimotopes, thus realizing the application of high-sensitivity detection methods such as ELISA and chemiluminescence in blood group antibody identification.

Effect of red blood cell storage duration on the clinical effect of exchange transfusion and internal environment in neonates with hyperbilirubinemia / 中国当代儿科杂志

OBJECTIVE@#To study the effect of red blood cell (RBC) storage duration on the clinical effect of exchange transfusion (ET) and internal environment in neonates with hyperbilirubinemia.@*METHODS@#A retrospective analysis was performed for the clinical data of 135 neonates with hyperbilirubinemia who received ET between January 2015 and August 2018. According to RBC storage duration, the neonates were divided into short-term storage group (RBCs were stored for ≤7 days) with 56 neonates and long-term storage group (RBCs were stored for >7 days) with 79 neonates. The two groups were compared in terms of serum total bilirubin (TBIL) level and the rate of TBIL reduction at 0 and 12 hours after ET, as well as the duration of continued phototherapy and rate of repeated ET. Routine blood test parameters, electrolytes, blood glucose, and blood gas parameters were measured before ET and at 0 hour after ET.@*RESULTS@#At 0 hour after ET, there were no significant differences in the TBIL level and the rate of TBIL reduction between the two groups (P>0.05). At 12 hours after ET, the long-term storage group had a significantly higher TBIL level and a significantly lower rate of TBIL reduction than the short-term storage group (P7 days in ET for neonates with hyperbilirubinemia does not affect the immediate effect of ET, but these neonates tend to have a poor outcome after continued phototherapy and high risk of hyponatremia, hyperkalemia, and metabolic acidosis.

Changes in Metabolism and Function of Platelets Stored at Different Temperature / 中国实验血液学杂志

@#AAbstractObjective:To compare and analyze the metabolic and functional changes in platelets stored at 4 ℃ and ones stored at 22 ℃ with agitation so as to provide an experimental basis for the cryopreservation technology of platelets.@*METHODS@#Samples were collected from platelets stored at 4 ℃ in 2, 4, 6, 11, 15 and 21 days, and from ones stored at 22 ℃ with agitation during the same days, the metabolism indicators and thromboelastogram (TEM) were analysed.@*RESULTS@#In metabolism, there were no significant changes of pH, GLU，PCO2, PCO2 and MPV levels of platelets stored at 4 ℃ for <6 days (P＞0.05), However, the Plt count decreased, the PDW and LDH level incrseased (P＜0.05). At the same time, only MPV had no changes of platelets stored at 22 ℃ during above-mentioned same days (P＞0.05), while the pH, PCO2, GLU, Plt all decreased, and PO2, LDH, PDW incrseased (P＜0.05). There were significant changes about the pH value, PO2, Plt, MPV, LDH, GLU levels between the two kinds of stored platelets during the same storing period (P＜0.05). The pH value and MPV of platelets stored at 4 ℃ were obviously lower than ones stored at 22 ℃, while GLU, PO2, LDH and Plt levels showed reverse changes (P＜0.05). Meanwhile, the PCO2 of platelets stored at 4 ℃ not could be detected and the Plt count reduced rapidly from d15. In function, the MA level of platelets stored at 4 ℃ was slower than that of platelets stored at 22 ℃, that is, the MA level of platelets stored at 4 ℃ were higher than that of platelets stored at 22 ℃ during the same storeing period (P＜0.05).@*CONCLUSION@#Platelets stored at 4 ℃ have much slower metabolism than ones stored at 22 ℃, and the aggregation is stronger of platelets stored at 4 ℃ than that of ones at 22 ℃ during the same conservation period.