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Objective:To investigate the molecular pathogenesis of a newly discovered gene mutation in a family with hereditary coagulation factor Ⅺ(FⅪ) deficiency.Methods:The proband was admitted to the First Affiliated Hospital of Wenzhou Medical University in September 2021 due to "calculus of intrahepatic duct". The patient had no symptoms of spontaneous bleeding.The clinical data and blood samples of the proband and her family members (10 persons in 3 generations) were collected.The activated partial thromboplastin time (APTT) and FⅪ activity (FⅪ:C) were performed by the one-stage clotting assay. FⅪ antigen (FⅪ:Ag) were detected by enzyme linked immunosorbent assay (ELISA). Genomic DNA extracted from peripheral blood cells of subjects was used as template to analyze F11 gene mutation by DNA direct sequencing. Bioinformatics software was used to analyze the effects of mutations on protein structure and function. Wild-type and mutant FⅪ protein expression vectors were constructed and transient transfected into HEK293T cells. The total RNA was extracted from positive transfected cells and then reversely transcribed into cDNA. The mRNA expression level of F11 gene in transfected cells was detected by real-time fluorescence quantitative PCR (qRT-PCR). The content of FⅪ:Ag and the expression of FⅪ protein in transfected cell lysates and culture supernatant were detected by ELISA and western blot.Results:The APTT of the proband was significantly prolonged to 107.9s (reference range 29.0-43.0s), while FⅪ:C and FⅪ:Ag were significantly decreased to 2% (reference range 84%-122%) and 5% (reference range 76%-127%), respectively. Gene sequencing analysis indicated that the proband had c.536C>T (p.Thr161Met) heterozygous missense mutation and c.1556G>A (p.Trp501Ter) heterozygous nonsense mutation in exon 6 and 13 of the F11 gene, respectively. Bioinformatics analysis showed that the amino acids at site 161 of FⅪ protein were threonine (Thr) in the matrix composed of five different species, indicating that Thr161 site was highly conserved among homologous genes in different species. p.Thr161Met heterozygous mutation affected the stability of local intermolecular structure of FⅪ protein. In vitro expression experiments of p.Thr161Met mutation showed that FⅪ protein had a normal synthesis in the cells but secretion dysfunction.Conclusions:c.536C>T (p.Thr161Met) heterozygous missense mutation and c.1556G>A (p.Trp501Ter) heterozygous nonsense mutation were mainly responsible for the decrease of FⅪ in this family. p.Thr161Met mutation was first reported in the world and did not affect the normal synthesis of FⅪ protein, but caused secretion dysfunction.
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【Objective】 To analyze the causes and treatments for the incompatible crossmatching between a patient, who underwent the minor ABO mismatches lung transplantation, and the blood donor with ABO-compatible blood. 【Methods】 A patient, who underwent the minor ABO mismatches (donor group O; recipient group A) lung transplantation developed a continuous decrease in Hb for 13 days after surgery, The blood sample of the patient presented major crossmatching incompatibility with the blood donors and the causes of it were analyzed by the recipient′s blood type reviewing, direct antiglobulin test, antibody screening and erythrocyte elution. 【Results】 The patient’s serum reacted with A1 erythrocyte reagent with agglutination strength at ±, and enhanced to 1+ at 4℃ after 10 min incubation.Antibodies were not detected by 10-cell panel and the effects of unexpected antibodies were excluded.The results of direct antiglobulin test and elution test were positive, and eluted anti-A antibody was detected.Combined with the patient′s continuous decline in Hb and elevated total bilirubin, passenger lymphocyte syndrome (PLS) was clinically diagnosed.After the transfusion of 6 U of O-type washed RBCs, the symptoms of anemia were improved and no adverse reactions occurred. 【Conclusion】 PLS may occur after an ABO mismatched solid organ transplantation.Most of the hemolytic symptoms are not obvious and easy to ignore, therefore clinical indicators of direct antiglobulin test results, Hb and total bilirubin should be continuously monitored after transplantation for early detection and timely treatment of PLS to avoid major adverse consequences.
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【Objective】 To explore the clinical value of thromboelas-tography, coagulation four items and platelet count in guiding platelet transfusion in critically ill patients. 【Methods】 A total of 188 critically ill patients in Intensive Care Unit of our hospital from January 2020 to January 2022 were selected as subjects, and were divided into study group(n=89) and the control(n=99) according to the presence of bleeding symptoms. T-test was used for comparative analysis between the two groups. Spearman was used to analyze the correlation between TEG, coagulation four items and platelet count, and binary Logistic regression analysis was used to predict the influential factors of bleeding in critically ill patients, ROC curve was used to analyze the guiding value of the above-mentioned indexes for platelet transfusion. 【Results】 1) K and PT values in the study group, above the normal range, were significantly higher than those in the control, while the Angle value, MA value, CI value, FIB value and platelet count were significantly lower than those of the control, among which MA value, CI value and platelet count were below the normal range. 2) TEG, coagulation four items and platelet count were correlated. MA and CI values were positively correlated with platelet count, instead, R and K values were negatively correlated. R value was positively correlated with PT and APTT, CI value, on the contrary, was negatively correlated, K value was positively correlated with PT, while Angle value and MA value were negatively correlated. 3) Binary Logistic regression analysis showed that decreased MA value and decreased platelet count were independent risk factors for predicting bleeding in critically ill patients(P<0.05). 4) ROC curve analysis showed that the areas under ROC curve corresponding to Angle value, MA value, CI value, FIB value and platelet count were 0.866, 0.932, 0.9, 0.838 and 0.987(P<0.05). The sensitivity was highest in platelet count and lowest in FIB. The specificity was highest in MA and lowest in Angle. Compared with the single index, the area under the curve of the combined index(K value, MA value, CI value, PT value and platelet count) was 0.995(P<0.05), Yoden index 0.944, sensitivity 100%, specificity 93.3%, all higher than the individual index. 【Conclusion】 Thromboelas-tography combined with coagulation four items and platelet count can be used to accurately predict the critically ill patients with bleeding risk. To guide clinical platelets transfusion, the combined use of indexes, including K value, MA, CI value, PT and platelet count, is superior to separate use of them as the former showed better sensitivity and specificity, demonstrating a good clinical value.
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BACKGROUND:The number of hematopoietic stem cel s in the peripheral blood is very low at normal physiological state. So it is critical to mobilize hematopoietic stem cel s from donor’s bone marrow into the peripheral blood. OBJECTIVE:To study the combination effect of AMD3100 and dexamethasone on the mobilization of hematopoietic stem cel s in mice, thereby laying the foundation for clinical application. METHODS:C57BL/6 mice were injected with AMD3100 and dexamethasone alone or in combination. Then, hematopoietic stem cel s in the peripheral blood and bone marrow were col ected. CD34+cel concentration in the peripheral blood and bone marrow was determined by flow cytometer and the content of leucocytes in the peripheral blood was counted by a normal method. The CFU-Mix colony formation ability of hematopoietic stem cel s was identified by cel colony forming assay. RESULTS AND CONCLUSION:The concentration of CD34+cel s in the peripheral blood and bone marrow, the content of leukocytes in the peripheral blood and the CFU-Mix colony formation ability of hematopoietic stem cel s were al improved by both AMD3100 and dexamethasone and especial y their combined use. This indicates that both AMD3100 and dexamethasone could mobilize hematopoietic stem cel s to migrate from the bone marrow to the peripheral blood, and when used in combination, the mobilization effect is better than that of single drug.