Changes of intestinal flora in children with acute lymphoblastic leukemia before and after chemotherapy / 中国当代儿科杂志

OBJECTIVES@#To examine the changes of intestinal flora in children newly diagnosed with acute lymphoblastic leukemia (ALL) and the influence of chemotherapy on intestinal flora.@*METHODS@#Fecal samples were collected from 40 children newly diagnosed with ALL before chemotherapy and at 2 weeks, 1 month, and 2 months after chemotherapy. Ten healthy children served as the control group. 16S rDNA sequencing and analysis were performed to compare the differences in intestinal flora between the ALL and control groups and children with ALL before and after chemotherapy.@*RESULTS@#The ALL group had a significant reduction in the abundance of intestinal flora at 1 and 2 months after chemotherapy, with a significant reduction compared with the control group (P<0.05). Compared with the control group, the ALL group had a significant reduction in the diversity of intestinal flora before and after chemotherapy (P<0.05). At the phylum level, compared with the control group, the ALL group had a significant reduction in the relative abundance of Actinobacteria at 2 weeks, 1 month, and 2 months after chemotherapy (P<0.05) and a significant increase in the relative abundance of Proteobacteria at 1 and 2 months after chemotherapy (P<0.05). At the genus level, compared with the control group, the ALL group had a significant reduction in the relative abundance of Bifidobacterium at 2 weeks, 1 month, and 2 months after chemotherapy (P<0.05); the relative abundance of Klebsiella in the ALL group was significantly higher than that in the control group at 1 and 2 months after chemotherapy and showed a significant increase at 1 month after chemotherapy (P<0.05); the relative abundance of Faecalibacterium in the ALL group was significantly lower than that in the control group before and after chemotherapy and showed a significant reduction at 2 weeks and 1 month after chemotherapy (P<0.05). The relative abundance of Enterococcus increased significantly at 1 and 2 months after chemotherapy in the ALL group (P<0.05), and was significantly higher than that in the control group (P<0.05).@*CONCLUSIONS@#The diversity of intestinal flora in children with ALL is significantly lower than that in healthy children. Chemotherapy significantly reduces the abundance of intestinal flora and can reduce the abundance of some probiotic bacteria (Bifidobacterium and Faecalibacterium) and increase the abundance of pathogenic bacteria (Klebsiella and Enterococcus) in children with ALL.

Clinical characteristics and risk factors of pericardial effusion after hematopoietic stem cell transplantation in children with thalassemia major / 中华儿科杂志

Objective: To investigate the characteristics, risk factors and outcomes of thalassemia major (TM) children with pericardial effusion (PE) after allo-geneic hematopoietic stem cell transplantation (allo-HSCT). Methods: Clinical data of 446 TM children received allo-HSCT at Shenzhen Children's Hospital between January 2012 and December 2020 were analyzed retrospectively. Patients were divided into PE and non-PE group according to the occurrence of PE. Chi-square tests were used to investigate the risk factors that were associated with the development of PE. Kaplan-Meier method was used for survival analysis of the 2 groups. Results: Twenty-five out of 446 patients (5.6%) developed PE at a time of 75.0 (66.5, 112.5) days after allo-HSCT. Among these patients, 22 cases (88.0%) had PE within 6 months after allo-HSCT and 19 patients (76.0%) had PE within 100 days after allo-HSCT. The diagnoses of PE were confirmed using echocardiography. Pericardial tamponade was observed in only 1 patient, who later undergone emergency pericardiocentesis. The rest of patients received conservative managements alone. PE disappeared in all patients after treatment. Risk factors that were associated with the development of PE after allo-HSCT included the gender of patients, the type of transplantation, the number of mononuclear cells (MNC) infuse, pulmonary infection after HSCT and transplantation associated thrombotic microangiopathy (TA-TMA) (χ²=3.99, 10.20, 14.18, 36.24, 15.03, all P<0.05). In 239 patients that received haploidentical HSCT, the development of PE was associated with the gender of patients, pulmonary infection after HSCT and TA-TMA (χ²=4.48, 20.89, 12.70, all P<0.05). The overall survival rates of PE and non-PE groups were 96.0% (24/25) and 98.6% (415/421). The development of PE was not associated with the overall survival of TM children after allo-HSCT (χ²=1.73, P=0.188). Conclusions: PE mainly develop within 100 days after allo-HSCT in pediatric TM recipients. Haploidentical grafts, female gender, pulmonary infection after HSCT and TA-TMA are the main risk factors associated with PE development after transplant. However, the presence of PE don't have a significant impact on the outcomes of pediatric TM patients after allo-HSCT.

Prognostic Factors Analysis of Children with Hemophagocytic Lymphohistiocytosis / 中国实验血液学杂志

OBJECTIVE@#To analyze the risk factors affecting prognosis of children with hemophagocytic lymphohistiocytosis (HLH).@*METHODS@#The clinical manifestations and laboratory data of 143 HLH children who met the HLH-2004 diagnostic criteria in Shenzhen Children's Hospital from January 2009 to May 2017 were retrospectively analyzed, and the independent factors affecting prognosis were also analyzed.@*RESULTS@#The median age of 143 HLH children was 1.9 (0.1-14.3) years old, and the median follow-up time was 6.7 years (1 day - 11.9 years). The overall survival rate of 1 month, 1 year, and 10 years was (87.4±5.5)%, (81.1±6.5)%, and (81.1±6.5)%, respectively. The deaths occurred within 1 year after onset. Multivariate analysis showed that central nervous system (CNS) involvement (P=0.047), low hemoglobin (P=0.002), prolonged activated partial thromboplastin time (APTT) (P<0.001), high triglyceride (P=0.005) were all the independent risk factors affecting survival of the children. Receiver operating characteristic curve indicated that APTT (AUC=0.753, P<0.001) was more valuable than other risk factors in predicting death of the children. The cut-off value of APTT was 56.6 s, and the sensitivity and specificity of which was 55.6% and 89.7%, respectively.@*CONCLUSION@#Hypohemoglobinemia, prolonged APTT, hypertriglyceridemia, and CNS involvement the risk factors affecting prognosis of HLH, and prolonged APTT shows a strong predictive value for death.

Genotypic and Phenotypic Analysis of αβ-Thalassemia in Children / 中国实验血液学杂志

OBJECTIVE@#To analyze the genotype and hematological characteristics of children with αβ-thalassemia in Shenzhen area of China.@*METHODS@#The erythrocyte parameters and hemoglobin components of the children were determined by blood routine examination and capillary electrophoresis (CE). Reverse dot blot (RDB) -polymerase chain reaction (PCR) was used to determine gene mutations in α- and β-thalassemia children. The Gap-PCR was used to determine the gene deletion of α-thalassemia children，while specimens suspected HKαα were determined with nested PCR.@*RESULTS@#Total of 29 complex genotypes were detected from 74 cases of αβ-thalassemia, among which 1 case was determined as β-thalassemia with αααanti4.2/αα and 5 cases were double heterozygous β-thalassemia combining α-thalassemia with intermediate phenotype. 1 case of β-28/βcap+40-43 double heterozygotes combined with --/αα and the other 62 cases were characterized by light β-thalassemia, 2 cases ofβCAP+40-43/βN with --/αα showed light α-thalassemia.@*CONCLUSION@#The genotypes of αβ-thalassemia in Shenzhen area of China are complex and diverse. The common complex genotypes are similar to those of simple β-thalassemia. If the genotype and phenotype are not consistent, the existence of rare genotype should be considered.

Evaluation of heart and liver iron deposition status in patients with β- thalassemia intermedia and major with MRI T2* technique / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the status of iron deposition in patients with β-thalassemia intermedia and major in mainland China.</p><p><b>METHODS</b>The status of transfusion and chelation was examined in 39 patients with β-thalassemia intermedia or major. Serum ferritin levels were measured. MRI T2* technique was used to detect cardiac and hepatic iron deposition.</p><p><b>RESULTS</b>Serum ferritin levels ranged from the minimum of 1500 ng/mL up to a maximum of 11491 ng/mL. From liver MRI T2* measurement, 15 cases had severe hepatic iron deposition (38%) and moderate deposition was found in 15 cases (38%), mild in 7 cases (18%), and normal in 2 cases (5%). Heart MRI T2* showed severe heart iron deposition in 7 cases (18%), mild in 5 cases (13%), and normal in 27 cases (69%). One case had cardiac arrhythmia. Four cases were over 20 years of age, and presented with gonadal function hypoplasia. The majority of patients did not receive regular transfusion and they had delayed, suboptimal chelation due to financial problems. Serum ferritin level was closely related with timing and dosage of chelation.</p><p><b>CONCLUSIONS</b>In patients with β-thalassemia who do not receive early regular transfusion and iron chelation therapy, iron deposition may occur at an early age. Important organs and tissue functional lesions and related complications also result. Relevant agencies and family members should be aware of this trend and develop appropriate strategies to improve the medical condition and quality of life of patients with this disorder.</p>

Analysis of the risk factors for hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation for beta-thalassemia in children / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the risk factors of hemorrhagic cystitis after allogeneic hematopoietic stem cell transplantation for beta-thalassemia in children.</p><p><b>METHODS</b>The clinical records of 30 children with beta-thalassemia undergoing allogeneic hematopoietic stem cell transplantation between December, 2008 and November, 2009 were analyzed.</p><p><b>RESULTS</b>Hemorrhagic cystitis occurred in 8 of the 33 patients with an incidence of 24.24%, including 1 with grade I, 6 with grade II and 1 with grade III hemorrhagic cystitis. The median time of hemorrhagic cystitis onset was 22.9 days (range 6-35 days) and the median duration was 11.9 days(range 3-27 days). Univariate analysis indicated that the different types of transplantation and acute graft-versus-host disease affect the occurrence of hemorrhagic cystitis. The children with Allo-PBSCT had higher incidence than those receiving Allo-PBSCT+Allo-UBT and Allo-BMT (P<0.05). The children at an age >or=6 years had obviously higher incidence of hemorrhagic cystitis than those at younger ages.</p><p><b>CONCLUSION</b>Age is the major factor that affects the occurrence of hemorrhagic cystitis in children undergoing allogeneic hematopoietic stem cell transplantation for beta-thalassemia.</p>

Relationship between glucocorticoid receptors and glucocorticoid resistance in children with idiopathic thrombocytopenia purpura / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To identify the relationship between the expression of alpha and beta-isoforms of glucocorticoid receptors (GR) in peripheral blood mononuclear cells (PBMC) and glucocorticoid resistance in children with idiopathic thrombocytopenia purpura (ITP).</p><p><b>METHODS</b>Real-time PCR was used to detect the expression of GR alpha and GR beta mRNA in PBMC from 30 children with ITP (glucocorticoid-sensitive, n=18; glucocorticoid-resistant, n=12) and 10 healthy children (control group). Enzyme immunoassay was used to measure plasma levels of total glucocorticoids.</p><p><b>RESULTS</b>There were no significant differences in PBMC GR alpha mRNA levels among the glucocorticoid sensitive, the glucocorticoid-resistant and the control groups. Compared with the glucocorticoid-sensitive and the control groups, the expression of GR beta mRNA in the glucocorticoid-resistant group was significantly up-regulated (p<0.01). Plasma total glucocorticoids level in the glucocorticoid-resistant group was found to be much higher than that in the glucocorticoid-sensitive and the control groups (p<0.01).</p><p><b>CONCLUSIONS</b>The up-regulated expression of GR beta mRNA may associated with glucocorticoid resistance in children with ITP.</p>

Construction of pcDNA3.1(+)/A2E eukaryotic expression vector and its expression on K562 cell / 中国实验血液学杂志

To construct pcDNA3.1(+)/A2E eukaryotic expression vector and obtain a stable expression on HLA-I negative human K562 cell, PCR technique was employed to amplify A2E cDNA from the multi-cistron expression vector pG/A2E carrying HLA-E and HLA-A2 cDNA through internal ribozyme entry site (IRES), the cDNA was subcloned into vector pcDNA3.1(+), thus a eukaryotic expression was constructed and named pcDNA3.1(+)/A2E; then, the recombinant plasmid was transferred into the target cells, followed by screening with G418 and limiting dilution; finally, flow cytometry was adopted to detect HLA-E expression on the target cells. The results showed that HLA-E molecules were successfully expressed on K562 cells transfected with pcDNA3.1(+)/A2E (27.76%) and the expression of HLA-E molecules was not detected on K562 cells transfected with pcDNA3.1(+). It is concluded that the pcDNA 3.1(+)/A2E eukaryotic expression vector was successfully constructed and the HLA-E molecules were expressed on K562 cells. The data presented here would be expected to lay a good basis for the research of the molecular mechanism of HLA-E function and the interaction between HLA-E and the receptor on NK cells, as well as the influence of the expression of HLA-E in vitro on NK cells.

Study on the expansion of megakaryocyte progenitors in vitro from cord blood / 中国实验血液学杂志

This study was aimed to investigate the effect of various cytokines on megakeryocytes expansion in vitro from human cord blood CD34(+) cells in order to establish an optimal culture system for MK expansion. Mononuclear cells were obtained by Ficoll-Hapaque density gradient separation. CD34(+) cells were positively isolated using a CD34 progenitor cell isolation kit. CD34(+) cells were placed into 24 well plates at a concentration of 2 x 10(4) per well. Each well contained 1 ml of IMDM with the present of effective MK cells growth cytokines. Clonogenic potentials of MK progenitor were assayed using a methylcellulose cultures system. The results suggested that four cytokines (IL-3 + IL-6 + TPO + FLT3L) culture system could effectively induce and expand cord blood CD41(+) MK cells. The number of CD41(+) cells expanded 154.67 +/- 32.21-fold on day 7, and 193.23 +/- 25.24-fold on day 14. In conclusion, established expansion system in vitro for MK cells provides experimental foundation for recovery of platelets after cord blood transplantation.