Effect of polydatin on the proliferation and apoptosis of THP-1 cells and the mechanism / 中国当代儿科杂志

OBJECTIVES@#To explore the effect of polydatin on the proliferation and apoptosis of acute monocytic leukemia cell line THP-1 and the possible mechanism.@*METHODS@#After THP-1 cells were treated with polydatin at gradient concentrations for 24 hours and 48 hours, their proliferation was determined by CCK-8 assay, and half maximal inhibitory concentration (IC50) was calculated. Logarithmically growing THP-1 cells were divided into two groups, a polydatin treatment group (treated with IC50 of polydatin) and a blank control group (treated without polydatin solution), and incubated for 48 hours. Cell apoptosis and cell cycle were measured by flow cytometry. The expression levels of PI3K, AKT, p-AKT, mTOR, p-mTOR, p70 S6K, and p-p70 S6K proteins were measured by Western blotting.@*RESULTS@#After treatment with polydatin, the proliferation of THP-1 cells was strongly inhibited, and the IC50 at 48 hours was 1 800 μmol/L. After treatment with 1 800 μmol/L polydatin solution for 48 hours, the apoptosis rate of THP-1 cells increased significantly compared with the blank control group (P<0.05). The cell cycle was arrested in the G0/G1 and S phases, with a significantly increased proportion of cells in the G0/G1 phase and a significantly decreased proportion of cells in the S phase, as compared with the blank control group (P<0.05). The expression levels of PI3K, AKT, p-AKT, mTOR, p-mTOR, p70 S6K, and p-p70 S6K proteins decreased significantly compared with the blank control group (P<0.05).@*CONCLUSIONS@#Polydatin can effectively inhibit the proliferation, block the cell cycle, and induce the apoptosis of THP-1 cells, which may be related to inhibition of the PI3K/AKT/mTOR signaling pathway.

Clinical features and prognosis of malignancy-associated hemophagocytic lymphohistiocytosis in children: a clinical analysis of 24 cases / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the clinical features and prognosis of malignancy-associated hemophagocytic lymphohistiocytosis (MAHS) in children.</p><p><b>METHODS</b>A retrospective analysis was performed for the primary diseases, clinical features, and prognosis of 24 children with MAHS.</p><p><b>RESULTS</b>Among the 24 children, 11 (46%) had MAHS induced by tumor and 13 (54%) had chemotherapy-associated MAHS. As for primary diseases, 17 children had acute leukemia, 6 had lymphoma, and 1 had neuroblastoma. The most common clinical manifestations were pyrexia, respiratory symptoms, and hepatosplenomegaly. The most common laboratory abnormalities were hemocytopenia, elevated serum ferritin, and elevated lactate dehydrogenase. Of the 24 children, 22 were treated according to the HLH-2004 protocol and 2 gave up treatment; 18 children died, 1 was lost to follow-up, and 5 survived. The survival time ranged from 3 days to 2 years and 4 months (median 28 days).</p><p><b>CONCLUSIONS</b>Children with MAHS have various clinical features and extremely poor treatment outcomes.</p>

Clinical features of childhood hemophagocytic syndrome and its association with human parvovirus B19 infection / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the association of childhood hemophagocytic syndrome (HPS) with human parvovirus B19 (HPVB19) infection, and to analyze the clinical features of this disease.</p><p><b>METHODS</b>ELISA and quantitative real-time PCR were used to detect HPVB19-IgM, HPVB19-IgG and HPVB19-DNA in 65 children with HPS (HPS group) and 65 healthy children (control group). The HPS group was divided into HPVB19-infected (n=14) and non-infected (n=51) groups according to the detection results of HPVB19-DNA. The clinical data of two groups were compared.</p><p><b>RESULTS</b>The positive rate of HPVB19-IgM in the HPS group (26%, 17/65) was significantly higher than that in the control group (9%, 6/65) (P=0.011), and there was no significant difference in the positive rate of HPVB19-IgG between the HPS (38%, 25/65) and control groups (29%, 19/65) (P=0.266). The infection rate of HPVB19 in the HPS group (22%, 14/65) was significantly higher than that in the control group (3%, 2/65) (P=0.001). Compared with the non-infected group, the HPVB19-infected group had significantly lower platelet count and hemoglobin level on admission, significantly more severe liver function damage, a significantly earlier onset time, and a significantly longer course of disease (P<0.05).</p><p><b>CONCLUSIONS</b>The pathogenesis of HPS may be associated with HPVBl9 infection. HPVBl9-infected children with HPS have more acute onset, more severe clinical manifestations, and a longer disease duration.</p>

Expression of CD58 in childhood B-lineage acute lymphoblastic leukemia and its feasibility in minimal residual disease detection / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To measure the expression of lymphocyte function-associated antigen-3 (CD58) in childhood B-lineage acute lymphoblastic leukemia (B-ALL) and to explore the feasibility of CD58 as an indicator for minimal residual disease (MRD) detection in childhood B-ALL.</p><p><b>METHODS</b>Eighty-seven children diagnosed with B-ALL between January 2014 and September 2014 were enrolled, and 20 hospitalized children who had no tumor or blood disease and had normal bone marrow cell morphology served as the control group. The expression features of CD58 in bone marrow samples from the two groups (at diagnosis, on day 15 of induction chemotherapy) were analyzed by four-color flow cytometry (FCM). Quantitative real-time polymerase chain reaction (qRT-PCR) and FCM were used to detect MRD in B-ALL patients on day 33 of induction chemotherapy.</p><p><b>RESULTS</b>The mean fluorescence intensity of CD58 expression in the 87 B-ALL cases (91±33) was significantly higher than that in the 20 controls (14±6) (P<0.01); CD58 was over-expressed in 44 of the B-ALL cases. In the B-ALL children, the expression of CD58 on day 15 of induction chemotherapy (105±22) was not significantly different from that at diagnosis (107±26) (P>0.05). In the 44 B-ALL patients with CD58 over-expression, FCM showed 9 MRD(+) cases and 35 MRD(-) cases, while qRT-PCR showed 11 MRD(+) cases and 33 MRD(-) cases; 42 cases (95%) showed consistent results of the two tests, so there was no significant difference between the two methods in detecting MRD (P>0.05).</p><p><b>CONCLUSIONS</b>CD58 is over-expressed and stable in children with B-ALL, and it can be considered as an indicator for MRD detection in childhood B-ALL.</p>

Roles of follicular helper T cells and follicular regulatory T cells in pathogenesis of Henoch-Schönlein purpura in children / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the roles of follicular helper T (Tfh) cells and follicular regulatory T (Tfr) cells in the pathogenesis of Henoch-Schönlein purpura (HSP) in children.</p><p><b>METHODS</b>Peripheral blood samples were collected from 40 HSP children and 25 healthy controls. The percentages of Tfh and Tfr cells were measured by flow cytometry; the mRNA expression levels of Bcl-6, c-MAF, Blimp-1, and PD-1 in peripheral blood were measured by real-time polymerase chain reaction.</p><p><b>RESULTS</b>Compared with the controls, the children with HSP had significantly increased percentage of Tfh cells and Tfh/Tfr ratio but a significantly reduced percentage of Tfr cells in the peripheral blood (P<0.05). Compared with the controls, the children with HSP had significantly increased mRNA expression of Bcl-6 and c-MAF but significantly reduced mRNA expression of Blimp-1 in CD4+ T cells (P<0.05), and had significantly increased mRNA expression of PD-1 but significantly reduced mRNA expression of Blimp-1 in CD4+CD25+ regulatory T cells (P<0.05).</p><p><b>CONCLUSIONS</b>Abnormal percentages of Tfh and Tfr cells may be involved in the pathogenesis of HSP in children, and over-expression of Bcl-6, c-MAF, and PD-1 mRNA and inhibited expression of Blimp-1 mRNA may be considered as important reasons for abnormal percentages of Tfh and Tfr cells.</p>

Prognostic significance of coagulation disorders in children with hemophagocytic syndrome / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the prognostic significance of coagulation disorders in children with hemophagocytic syndrome (HPS).</p><p><b>METHODS</b>Thirty-five children with HPS were retrospectively studied to analyze the etiology, clinical characteristics, laboratory results and treatment outcomes.</p><p><b>RESULTS</b>After treatment, 27 of the 35 HPS patients survived, and the other 8 cases died. All cases were treated according to the HLH-2004 protocol, but etoposide (VP-16) was not used in 10 of them. The response rate in patients who received VP-16 (22/25, 88%) was significantly higher than that in those not receiving VP-16 (5/10, 50%) (P<0.05). Compared with the survival group, the dead group had significantly lower platelet count, fibrinogen level, and VP-16 utilization rate (P<0.05) but significantly longer activated partial thromboplastin time and prothrombin time (P<0.05).</p><p><b>CONCLUSIONS</b>Coagulation function can be used as an indicator of disease outcome. It is essential for improving the clinical outcome of HPS to monitor the coagulation function during treatment, detect and correct abnormalities in time, and provide treatment strictly according to the HLH-2004 protocol.</p>

Latest update on immunotherapy of Epstein-Barr virus-associated post-transplantation lymphoproliferative disease / 中国当代儿科杂志

Epstein-Barr virus (EBV)-associated post-transplantation lymphoproliferative disease (EBV-PTLD) is a potentially life-threatening complication after hematopoietic stem cell transplantation or solid organ transplantation. In the last decade, the survival of patients with EBV-PTLD has been significantly improved by immunotherapeutic interventions among high-risk patients. The immunotherapeutic interventions for EBV-PTLD include reduction in immunosuppression, CD20 monoclonal antibodies (rituximab) as monotherapy or in combination with chemotherapy, and adoptive immunotherapy with EBV-specific T cells. This paper reviews the latest update on the high-risk factors, clinical manifestations and immunotherapy of EBV-PTLD.

Observation of high dose prednisone oral treatment in children with immune thrombocytopenia / 中华实用儿科临床杂志

Objective To explore curative effects of high-dose prednisone used for children with immune thrombocytopenia (ITP).Methods The children with ITP were divided into prednisone group,γ-globulin group and methylprednisolone group.Platelet levels in peripheral blood were recorded after treatments within the 5th day and the 30th day,and the blood pressure levels of children were also recorded during treatments.Thex2 test was used to compare the effective rate of different treatments as well as the incidence rate of hypertension in these 3 groups.Results In new diagnosis children,there was no significant difference in the effective rate among the 3 groups in the 5th day(P ＞ 0.05).The effective rate of prednisone group in the 30th day was significantly higher than γ-globulin group (P ＜0.05),and there was no significant difference than methylprednisolone group (P ＞ 0.05).In persistence and chronic ITP children,the effective rate of prednisone group were both significantly higher than those in γ-globulin group in the 5th days and the 30th day (P ＜0.05),and were also no significantly higher than those in methylprednisolone group (P ＞ 0.05).The incidence rate of hypertension was significantly lower in prednisone group than that in methylprednisolone group (P ＜ 0.05).Conclusion High-dose prednisone oral treatment is safe,effective and worth using in children with ITP.

Sorting,identification and enrichment of side population cells in acute monocytic leukemia THP-1 Cells / 中华实用儿科临床杂志

Objective To assay and determine whether the human acute monocytic leukemia cell line THP-1 contains side populations (SP) cells,and to increase the proportion of SP cells using cytarabine (Ara-C).Methods Fluorescent microscope and flow cytometry (FCM) were employed for detecting the percentage of SP cells in THP-1 cells.Then,SP and non-SP (NSP) subpopulations were collected and identified.Finally,THP-1 cells were incubated with different concentrations of Ara-C for 24 hours and detected the proportion of SP cells,respectively.Results The results demonstrated that the percentage of SP cells was (1.81 ± 0.99) ％ in THP-1 cells.A majority of the SP cells remained in the G0/G1 phase,and the expressions of CD34 + and CD34 + CD38-and the proliferative ability of the SP cells were higher than those of NSP cells (P ＜ 0.05).The mRNA expression of multidrug resistance genes (ABCG2,ABCB1),apoptosis regulation genes (Bcl-2) and the Bcl-2/Bax ratio of SP cells were higher than those of NSP cells.SP cells have been shown to be more tumorigenic than NSP cells.After co-culture with Ara-C,the proportion of SP cells increased significantly and presented in a concentration-dependent manor.Conclusions All of these findings suggest that the THP-1 cell line contains SP cells and the SP cells possess some intrinsic stem cell properties.The proportion of SP cells can be increased when co-cultured with Ara C,and this technique is a useful and important application for the study of LSCs.

Ultrastructural observation of Birbeck granules in 8 cases of Langerhans cell histiocytosis / 中华实用儿科临床杂志

Objective To study the ultrastructural features of Langerhans cell(LC),especially Birbeck granules in Langerhans cell histiocytosis(LCH) and provide some ultrastructural evidence to clarify the origin,function and stereoscopic structure of Birbeck granules.Methods Pathologic tissues of 8 LCH patients were treated with routine transmission electron microscope (TEM) procedures,fixture,dehydration,permeation,embedding,polymerization,ultramicrocut,staining and examined by TEM.Results Under the TEM,8 cases of LCH revealed typical LC cell,and LC cell in 6 cases revealed typical rod,tennnis-racquet like Birbeck granules.Some double membrane structures revealed irregular shape,sometimes accompanied with vacuole-like structure.Most of Birbeck granules locate inside the cytoplasmic membrane,in continuity with the cell membrane.There was Birbeck granule-like structure outside the cytoplasmic membrane in one case of multisystem LCH.Conclusions The ultrastructure of Birbeck granules could be various and irregular.The irregular Birbeck granule-like structure can also be useful for the diagnosis of LCH.Birbeck granules may arise from the cell membrane.The stereoscopic structure of Birbeck granules could be irregular.

Association between helicobacter pylori infection and chronic idiopathic neutropenia / 华中科技大学学报（医学）（英德文版）

The possible association between Helicobacter pylori (H. pylori) infection and chronic idiopathic neutropenia (CIN) was investigated. A total of 78 subjects with CIN were recruited in this case-control study. As a control group, 40 subjects without CIN were selected for comparison with the case group. All participants were evaluated for the prevalence of H. pylori infection by 14C-urea breath test. The corrected splenic index (CSI) was calculated, and serum IL-6, IL-8, IL-10 and HsCRP levels were measured. The differences in CSI, serum IL-6, IL-8, IL-10 and HsCRP levels were compared between CIN patients and controls, as well as between subjects with and without H. pylori infection. The positive rate of H. pylori was 87.18% in CIN group and 52.50% in control group, showing a significant difference (Fisher's exact, P=0.000). CSI values, and serum IL-6 and HsCRP levels in H. pylori positive-CIN patients were significantly higher than those in negative subjects (Mann-whitney U-test, P=0.016, P=0.001 and P=0.000 respectively), while IL-10 level declined significantly in H. pylori negative-CIN patients (Mann-whitney U-test, P=0.000). In control group, serum IL-6 and HsCRP levels in H. pylori positive individuals were also increased significantly (Mann-whitney U-test, P=0.000), while IL-10 level declined (Mann-whitney U-test, P=0.018). Multivariate regression analysis revealed that H. pylori infection and IL-10 were significant risk factors for CIN with odds ratio (OR): 3.09, 95.0% CI: 1.22-6.93; P=0.019, and OR: 0.17, 95.0% CI: 0.05-0.94; P=0.021, respectively. This prospective study confirmed the existence of an association between H. pylori infection and CIN, suggesting the screening for H. pylori infection and eradicating bacterium in positive cases seem appropriate and beneficial for those patients with CIN diagnosis.

Association between helicobacter pylori infection and chronic idiopathic neutropenia / 华中科技大学学报（医学）（英德文版）

The possible association between Helicobacter pylori (H. pylori) infection and chronic idiopathic neutropenia (CIN) was investigated. A total of 78 subjects with CIN were recruited in this case-control study. As a control group, 40 subjects without CIN were selected for comparison with the case group. All participants were evaluated for the prevalence of H. pylori infection by 14C-urea breath test. The corrected splenic index (CSI) was calculated, and serum IL-6, IL-8, IL-10 and HsCRP levels were measured. The differences in CSI, serum IL-6, IL-8, IL-10 and HsCRP levels were compared between CIN patients and controls, as well as between subjects with and without H. pylori infection. The positive rate of H. pylori was 87.18% in CIN group and 52.50% in control group, showing a significant difference (Fisher's exact, P=0.000). CSI values, and serum IL-6 and HsCRP levels in H. pylori positive-CIN patients were significantly higher than those in negative subjects (Mann-whitney U-test, P=0.016, P=0.001 and P=0.000 respectively), while IL-10 level declined significantly in H. pylori negative-CIN patients (Mann-whitney U-test, P=0.000). In control group, serum IL-6 and HsCRP levels in H. pylori positive individuals were also increased significantly (Mann-whitney U-test, P=0.000), while IL-10 level declined (Mann-whitney U-test, P=0.018). Multivariate regression analysis revealed that H. pylori infection and IL-10 were significant risk factors for CIN with odds ratio (OR): 3.09, 95.0% CI: 1.22-6.93; P=0.019, and OR: 0.17, 95.0% CI: 0.05-0.94; P=0.021, respectively. This prospective study confirmed the existence of an association between H. pylori infection and CIN, suggesting the screening for H. pylori infection and eradicating bacterium in positive cases seem appropriate and beneficial for those patients with CIN diagnosis.

Role of Helicobacter pylori infection in the pathogenesis and clinical outcome of childhood acute idiopathic thrombocytopenic purpura / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the role of Helicobacter pylori (Hp) and its products cytotoxin-associated protein (Cag A), vacuolating cytotoxin (VacA) in childhood acute idiopathic thrombocytopenic purpura (aITP), to evaluate the effect of Hp on their clinical outcome.</p><p><b>METHODS</b>Subjects were enrolled according to case-control design, including 184 aITP children and 154 healthy controls. They were inquired for demographic characteristics, the risk factors regarding Hp infection and ITP through a uniformed questionnaire. Patients with Hp infection were diagnosed by combined detection of serum Hp antibodies and stool antigens. CagA and VacA proteins were tested by ELISA method. In addition, clinical data and follow-up data of aITP children were collected. Non-conditional logistic regression and t test were applied for statistical analysis.</p><p><b>RESULTS</b>(1) The prevalence of Hp infection in aITP children and controls were 41.30% and 35.71%, respectively. No association between Hp infection and children aITP was found with OR of 1.170 (95%CI: 0.7163 - 1.673) after adjusting for confounding variables. (2) No statistical differences regarding initial platelet counts, megakaryocytes counts and the constituent ratio were found between the aITP children with and without Hp infection (P > 0.05). (3) No differences regarding initial platelet counts were found between aITP children with and without the expression of CagA (P > 0.05). The follow-up data showed that 32.88% of aITP children with Hp infection, as well as 29.70% of aITP children without Hp infection developed into cITP. No association between Hp infection and development to cITP was found with adjusted OR 1.171 (95%CI: 0.555 - 2.11 2).</p><p><b>CONCLUSIONS</b>The results didn't suggest that Hp is unlikely to play a role in the onset of childhood aITP, and in the development of aITP to cITP.</p>

Effectiveness of anti-CD47 antibody and Ara-C combination targeting therapy NOD/SCID mouse of myeloid leukemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the prognostic significance of CD47 in a NOD/SCID mouse model of acute myeloid leukemia (AML) and the best strategy for targeted therapy for this disease.</p><p><b>METHODS</b>CD34(+)CD38(-) leukemia stem cells (LSCs) were separated and transplanted into NOD/SCID mice to establish a mouse model of acute monocytic leukemia (AMoL). Anti-human CD47 antibody, alone or combined with cytosine arabinoside (Ara-C), was used to treat the mice with AMoL for 7-14 days, and therapeutic efficacy was assessed. LSCs were cultured together with mouse macrophages in culture medium containing anti-CD47 or anti-CD45 monoclonal antibody for 2 hours, to observe the phagocytic ability of macrophages to LSCs.</p><p><b>RESULTS</b>CD34(+)CD38(-) LSCs existed among THP-1 cells, with a content of about (0.12 ± 0.06)%, and a mouse model of AML was successfully established after the purified CD34(+)CD38(-) LSCs (97.0% ± 1.7%) were transplanted into NOD/SCID mice. The in vivo experiment showed that mice with AMoL had the most significant decrease in CD33(+)CD45(+) leukemia cells in peripheral blood and bone marrow and survived the longest after being treated with Ara-C (7 days) plus anti-CD47 monoclonal antibody (14 days) (P < 0.01). After 2 hours of in vitro culture, the phagocytic index in the culture medium containing anti-CD47 monoclonal antibody was significantly higher than in the culture medium containing anti-CD45 monoclonal antibody (76.9% ± 12.2% vs 7.60% ± 2.4%; P < 0.05).</p><p><b>CONCLUSIONS</b>High expression of CD47 is an adverse prognostic factor in AML. Combination therapy with anti-CD47 monoclonal antibody and Ara-C can effectively eliminate leukemia cells and LSCs, demonstrating great clinical significance in curing AML.</p>

Association between platelet-activating factor acetylhydrolase gene polymorphism and intracranial hemorrhage in preterm infants / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To explore whether Val279Phe single nucleotide polymorphisms (SNPs) in the 9th exon of platelet-activating factor acetylhydrolase (PAF-AH) are associated with intracranial hemorrhage in preterm infants.</p><p><b>METHODS</b>A case-control study was performed. Polymerase chain reaction (PCR) was used to test genotype and allele frequencies of the 9th exon Val279Phe SNPs of PAF-AH in 58 preterm infants with intracranial hemorrhage (hemorrhage group) and 65 preterm infants without intracranial hemorrhage (control group).</p><p><b>RESULTS</b>There were significant differences in genotype frequency of Val279Phe SNPs in the 9th exon of PAF-AH between the hemorrhage and control groups (P<0.05). Frequency of normal genotype in the hemorrhage group (63.8%) was significantly lower than in the control group (81.5%). In contrast, frequency of heterozygous genotype (34.5%) in the hemorrhage group was significantly higher than in control group (16.9%). There were also significant differences in allele frequency of Val279Phe SNPs in the 9th exon of PAF-AH between the two groups (P<0.05). T allele frequency in the hemorrhage group (19.0%) was significantly higher than in the control group (10.0%).</p><p><b>CONCLUSIONS</b>Val279Phe SNPs in the 9th exon of PAF-AH may be associated with intracranial hemorrhage in preterm infants.</p>

Efficacy of immunosuppressive therapy for children with aplastic anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effectiveness and safety of immunosuppressive therapy (IST) in the treatment of childhood aplastic anemia (AA) and to study the main factors influencing the effectiveness.</p><p><b>METHODS</b>The clinical data of 55 children with severe aplastic anemia (SAA) and 51 children with chronic aplastic anemia (CAA) were retrospectively analyzed. All patients received IST from January 2007 to December 2010.</p><p><b>RESULTS</b>In children with CAA, the effective rate of antithymocyte globulin (ATG) plus cyclosporine A(CsA) combination therapy was significantly higher than that of CsA alone (80% vs 44%; P<0.05); in children with SAA, the effective rate of ATG plus CsA combination therapy was also significantly higher than that of CsA alone (75% vs 40%; P<0.05). No patients developed clonal disease such as myelodysplastic syndrome, paroxysmal nocturn hemoglobinuria or acute myelocytic leukemia. In patients treated with the ATG plus CsA combination therapy, the response rate was relatively high for children whose disease course was less than six months, bone marrow hematopoietic area was more than 40%, had no severe infections, and experienced granulocyte colony stimulating factor (G-CSF) reaction during the early treatment; however, it was not related to AA subtypes and age.</p><p><b>CONCLUSIONS</b>ATG plus CsA combination therapy is effective and safe in the treatment of childhood AA. The disease course, bone marrow hematopoietic area, severe infections and G-CSF reaction to early treatment are the main factors influencing the therapeutic effects.</p>

Clinical efficacy of desmopressin in the treatment of mild hemophilia A in children / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effects of desmopressin (DDAVP) on coagulation factor Ⅷ (FⅧ) and activated partial thromboplastin time (APTT) in children with mild hemophilia A.</p><p><b>METHODS</b>Eighteen children with mild hemophilia A were enrolled. DDAVP (0.3 μg/kg•d) was injected intravenously for 5 days. Plasma FⅧ levels and APTT were measured before and after DDAVP treatment.</p><p><b>RESULTS</b>In 16 of 18 children with mild hemophilia A, the bleeding symptoms, including the articular or musclar hematoma, were significantly alleviated as a result of DDAVP treatment. The plasma FⅧ levels increased significantly to (27±4)% and APTT was shortened to (66±10)s 60 minutes after the first dose of DDAVP treatment. The plasma FⅧ remained at the levels of 25%-30% during 3-4 days of DDAVP treatment. Five days after DDAVP treatment, the plasma FⅧ levels decreased [(21±3)%], and APTT was prolonged when compared with 1-4 days of DDAVP treatment.</p><p><b>CONCLUSIONS</b>DDAVP treatment can increase plasma FⅧ levels and shorten APTT in children with mild hemophilia A. DDAVP is effective in the treatment of mild hemophilia A. The duration of DDAVP therapy for mild hemophilia A is recommended as 3 to 4 days.</p>

Cell proliferation and signal pathway after knockdown and RESC concurrent rescue of RNAi lentiviral vector on human PTEN gene in T-lymphocytes / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To construct the lentiviral expression vectors of human PTEN gene for RNA interference (RNAi) and concurrent rescue of RNAi escape strategy construct (RESC) and to observe the changes of signal pathway, cell proliferation and cell cycle after PTEN gene knockdown and RESC concurrent rescue in human T-lymphocytes, in order to provide an experimental basis for a further research into the pathogenesis of acute lymphoblastic leukemia in children.</p><p><b>METHODS</b>Using lentiviral vector systems to construct lentiviral vectors of human PTEN gene for RNAi and its RESC concurrent rescue, human T-lymphocytes were transfected with the lentiviruses. The cell models were established with PTEN gene knockdown (T-LC-shPTEN) and RESC concurrent rescue (T-LC-rrshPTEN). After knockdown and RESC concurrent rescue of PTEN gene, the expression of PTEN protein and the activation of AKT signal pathway, cell proliferation and cell cycle were detected by Western blot, MTT assay and flow cytometry respectively.</p><p><b>RESULTS</b>The RNAi-mediated lentiviruses can down-regulate the expression of the human PTEN gene effectively. After the down-regulation of PTEN gene, the T-lymphocytes grew faster. The phase G0/G1 cells decreased and the phases S and G2/M cells increased significantly. The PI3K/AKT signal pathway was activated. All RNAi phenomenon caused by PTEN gene knockdown were recovered fully by RESC concurrent rescue of RNAi.</p><p><b>CONCLUSIONS</b>The lentiviral expression vectors of human PTEN gene for RNAi and RESC concurrent rescue of RNAi are constructed successfully. The PI3K/AKT signal pathway can be activated and the proliferation of human T-lymphocytes can be promoted after PTEN gene knockdown.</p>

Levels of Toll-like receptors-2,-4 on platelets in children with idiopathic thrombocytopenic purpura / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the changes and significance of Toll-like receptor-2 (TLR2) and Toll-like receptor-4 (TLR4) on platelets, CD86 on lymphocytes and concentrations of IL-2, IFN-gamma, IL-4 and IL-10 in serum in children with idiopathic thrombocytopenic purpura (ITP).</p><p><b>METHODS</b>Peripheral blood samples were collected from 24 children with acute idiopathic thrombocytopenic purpura (AITP), 21 children with chronic idiopathic thrombocytopenic purpura (CITP) and 20 normal children (control group). Expression of TLR2 and TLR4 on platelets and CD86 on lymphocytes were detected by flow cytometry. Serum concentrations of IL-2, IL-4, IL-10 and IFN-gamma were measured using ABC-ELISA.</p><p><b>RESULTS</b>The expression of CD41+TLR2+ and CD61+TLR4+ in the AITP and the CITP groups were significantly lower than those in the control group (p<0.01). The AITP group had lower expression of CD41+TLR2+ and CD61+TLR4+ than the CITP group (p<0.01). The expression of CD86+ in the AITP and the CITP groups was significantly higher than that in the control group (p<0.01). The serum concentrations of IL-2, IL-4, IL-10 and IFN-gamma in the AITP and the CITP groups were significantly higher than those in the control group (p<0.05). There was a positive correlation between CD41+TLR2+ and CD61+TLR4+ expression. CD41+TLR2+ and CD61+TLR4+ expression were negatively correlated with CD86+ expression and serum concentrations of IL-2, IL-4 and IL-10.</p><p><b>CONCLUSIONS</b>The detections of TLR2 and TLR4 on platelets, CD86 on lymphocytes and serum concentrations of IL-2, IFN-gamma, IL-4 and IL-10 are of great value in understanding the pathogenesis and predicting types of ITP in children.</p>

In vitro transcription synthesis and effects of FLT3 targeted short hairpin RNA / 中国实验血液学杂志

FMS-like tyrosine kinase 3 (FLT3) is a receptor of tyrosine kinase that is constitutively activated in most of acute myeloid leukemia patients and seems to give an adverse prognosis. In order to explore the silencing effect of FLT3 targeted short hairpin RNA (FLT3-shRNA) on acute leukaemia cell line THP-1, three FLT3-shRNAs (shRNA1, shRNA2, shRNA3) were designed and synthesized by transcription system in vitro and then transfected into THP-1 cells. FLT3 mRNA was analyzed by semi-quantitative RT-PCR, FLT3 protein was detected by Flow cytometry and immunofluorescence. The results indicated that FLT3 expression was downregulated by shRNA1 and shRNA3, and shRNA1 showed stronger inhibitory effect. At 48 hours following transfection, the inhibitory rate of 25 nmol/L shRNA1 was 72.95 +/- 2.07%, lasting 72 hours. The 5 nmol/L and more concentration of FLT3 shRNA1 could downregulate FLT3 mRNA level, which displayed a quantity-effect relation; the inhibitory rate of 15 nmol/L shRNA1 was 67.53 +/- 0.66%. FLT3 protein was located on THP-1 cell membrance, its expression was downregulated obviously by shRNA1, at 72 hours following transfection the inhibitory rate of shRNA1 was 79.67 +/- 0.66%. shRNA1 showed the best inhibitory effect on FLT3 protein, the optimal time of which was 72 hours with an inhibitory rate of 79.67%. It is concluded that FLT3-shRNA1 shows a desireable FLT3-targeted inhibitory effect, which can be used for further investigation of FLT3 mechanism or FLT3 targeting treatment.