Detection of RAS gene mutation and its clinical significance in children with acute lymphoblastic leukemia / 中国当代儿科杂志

OBJECTIVES@#To investigate the mutation rate of the RAS gene and its clinical significance in children with acute lymphoblastic leukemia.@*METHODS@#A retrospective analysis was performed on the medical data of 120 children with newly diagnosed acute lymphoblastic leukemia, who were admitted to the Third Affiliated Hospital of Zhengzhou University from January 2015 to January 2020 and underwent next-generation sequencing. The clinical and molecular features were analyzed. The impact of RAS gene mutation on the overall survival rate was evaluated in these children.@*RESULTS@#Among the 120 children, 35 (29.2%) had RAS gene mutation, 30 (25.0%) had KRAS gene mutation, and 5 (4.2%) had both NRAS and KRAS gene mutations. All NRAS mutations and 71% (25/35) of KRAS mutations were located at the 12th and 13th codons. RAS gene mutation was detected in 35 (33.3%) out of 105 children with B-lineage acute lymphoblastic leukemia, but it was not detected in those with acute T lymphocyte leukemia. Of all the children, 11 (9.2%) were lost to follow-up, and among the 109 children followed up, 16 (14.7%) died. The children with RAS gene mutation had a significantly lower 2-year overall survival rate than those without RAS gene mutation (P<0.05). The prognosis of children with RAS gene mutation combined with WT1 overexpression and WBC>50×109/L at diagnosis was worse (P<0.05).@*CONCLUSIONS@#RAS gene mutation is commonly observed in children with B-lineage acute lymphoblastic leukemia and may have an adverse effect on prognosis.

Measurement of Foxp3 and NFAT1 in children with aplastic anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the expression of Foxp3 and NFAT1 protein in peripheral blood (PB) in children with aplastic anemia (AA) and their roles in the pathogenesis of AA.</p><p><b>METHODS</b>The expression levels of Foxp3 and NFAT1 protein of mononuclear cells in PB were measured by Western blot in 68 children with AA before and after treatment and in 60 normal children (control group). The correlation between Foxp3 and NFAT1 protein expression and the correlation of the Foxp3 and NFAT1 protein expression with blood Hb, WBC and platelet levels were analyzed.</p><p><b>RESULTS</b>The expression levels of Foxp3 and NFAT1 protein in PB in the acute phase in the AA group were significantly lower than in the control group (P<0.05). After treatment (recovery phase) the expression levels of Foxp3 and NFAT1 protein increased obviously compared with those in the acute phase (P<0.05). The Foxp3 protein level was positively correlated with the NFAT1 protein level (r=0.812, P<0.05). Both the Foxp3 and NFAT1 protein levels were positively correlated with blood Hb, WBC and platelet levels in children with AA in the recovery phase (r=0.537, 0.579, 0.655 respectively; P<0.05).</p><p><b>CONCLUSIONS</b>The Foxp3 and NFAT1 protein levels in PB are reduced in children with AA, suggesting that they are involved in the pathogenesis of AA. The measurement of Foxp3 and NFAT1 protein levels may be useful in the severity evaluation of AA.</p>

Telomere length and telomerase mutations in peripheral blood leukocytes of children with chronic aplastic anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the change in telomere length and TERC and TERT mutations in peripheral blood leukocytes of children with chronic aplastic anemia (CAA).</p><p><b>METHODS</b>Sixty-nine children with CAA were divided into untreated group (n=24) who did not receive immunosuppressive therapy (IST), response group (n=36) who showed response to IST, and non-response group (n=9) who showed no response to IST; another 35 healthy children matched for age and sex were selected as the control group. The telomere-to-single copy gene (T/S) ratio in peripheral blood leukocytes was measured by real-time PCR in all groups. PCR was performed to detect TERC and TERT mutations in all children with CAA.</p><p><b>RESULTS</b>The untreated and non-response groups had significantly lower T/S ratios than the control and response groups (P<0.01), whereas there was no significant difference in T/S ratio between the response and control groups (P>0.05). TERC and TERT mutations were not found in all children with CAA.</p><p><b>CONCLUSIONS</b>The change in telomere length in children with CAA may be related to the development and progression of disease. Telomere length measurement may be used as a prognostic indicator in children with CAA.</p>

Prevalence and risk factor analysis of methicillin-resistant Staphylococcus aureus skin colonization in neonatal intensive care unit / 中华实用儿科临床杂志

Objective To analyze the prevalence and risk factor of methicillin-resistant Staphylococcus aureus (MRSA) skin colonization in neonatal intensive care unit (NICU).Methods One thousand six hundred and seventyeight newborns (938 boys and 740 girls) in NICU were selected,with a mean age of (5.9 ±6.4) days,ranging from 1 to 28 days.Nasal swabs were collected by medical cotton and Staphylococcus aureus (SA) was isolated.All of SA was detected and the mecA gene was detected to determine MRSA through PCR method.The rate of MRSA skin colonization was recorded,and the correlation was analyzed between the rate of MRSA skin colonization and some parameters.The rates of MRSA skin colonization of different time points were compared.Results In NICU,the rate of SA and MRSA skin colonization were 21.10％ (354/1678 cases) and 3.69％ (62/1678 cases),respectively.With the prolongation of hospital stay,the rate of MRSA skin colonization increased,in the order of 7 d ＞ 3 d ＞ 1 d,and the differences were statistically significant (P ＜ 0.05).But the rates of MRSA skin colonization had no significant difference between 7 d and 14 d (P ＞ O.05).Logistic regression analysis showed negative correlation between gestational age,weight,and Apgar scores with MRSA skin colonization but positive correlation between surgery or invasive procedures and antibiotics exposure with MRSA skin colonization.Conclusions Newborns in NICU have high rate of MRSA skin colonization.With the prolongation of hospital stay,the rate of MRSA skin colonization has an increase within 7 days.Gestational age,weight,Apgar scores,surgery or invasive procedures and antibiotics exposure are risk factors of newborn MRSA skin colonization.

Expression of telomerase activity and its related genes in the marrow hemopoietic stem cells of children with aplastic anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To explore the relationship of telomerase RNA component (hTERC) and the telomerase reverse transcriptase (hTERT) with telomerase activity in the marrow hemopoietic stem cells of children with aplastic anemia (AA).</p><p><b>METHODS</b>Fifty-two children with chronic AA, 13 children with acute AA and 21 normal controls were enrolled in the study. Telomerase activity and the expression of mRNA of hTERT and hTERC were detected by Telomeric Repeat Amplification Protocol (TRAP) with silver staining and real-time Q-PCR respectively.</p><p><b>RESULTS</b>Levels of telomerase activity in both the chronic and acute AA groups were higher than in the control group (P<0.01). The AA groups had significantly higher expression of hTERT mRNA than the control group (P<0.01). The chronic AA group had higher expression of hTERT mRNA and telomerase activity than the acute AA group (P<0.05). There was no significant difference in the expression of hTERC mRNA among the three groups (P=0.812). There was a significant correlation between the expression of hTERT mRNA and telomerase activity (r=0.660, P<0.01).</p><p><b>CONCLUSIONS</b>Expression of telomerase activity may be involved in the pathophysiology and development of AA, and hTERT plays a crucial role in expression of telomerase activity.</p>

Effect of cyclosporine on regulatory T cells and Foxp3 in the peripheral blood of children with chronic aplastic anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To explore the expression diversification of CD4(+)CD25(+)CD127(low) regulatory T (Treg) cells and Foxp3 mRNA in the peripheral blood of children with aplastic anemia after the treatment with cyclosporine.</p><p><b>METHODS</b>Fifty children with chronic aplastic anemia were enrolled, among whom 30 received cyclosporine treatment (cyclosporine group) and 20 were treated with conventional methods (conventional group). Twenty healthy children were enrolled as the control group. The expression of CD4(+)CD25(+)CD127(low) Treg cells was detected by flow cytometry. The expression of Foxp3 mRNA was detected by real-time Q-PCR.</p><p><b>RESULTS</b>The expressions of Foxp3 mRNA and CD4(+)CD25(+)CD127(low)Treg cells showed no significant difference between the cyclosporine and the control groups 6 months after treatment. On the contrary, there were significantly lower expressions of both in the conventional group than in the control group (P<0.05). Meanwhile, the cyclosporine group had significantly higher expressions of Foxp3 mRNA and CD4(+)CD25(+)CD127(low) Treg cells than the conventional group (P<0.05).</p><p><b>CONCLUSIONS</b>The expressions of CD4(+)CD25(+)CD127(low) Treg cells and Foxp3 mRNA in children with aplastic anemia increase after cyclosporine treatment.</p>

Detection and significance of CD4+ CD25int/high CD127low regulatory T cells in pediatric aplastic anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the expression of CD4+ CD25int/high CD127low regulatory T cells in peripheral blood (PB) and its relation to the quantity of Hb, WBC and platelet (Plt) in children with aplastic anemia (AA).</p><p><b>METHODS</b>Expression of CD4+ CD25int/high CD127low in PB was detected by flow cytometry in 22 children with AA before and after treatment and in 15 healthy controls. The relationships between CD4+CD25highCD127low and the quantity of Hb, WBC and Plt were evaluated.</p><p><b>RESULTS</b>Compared to controls, the percentages of CD4+ CD25+/CD4+, CD4+CD25high/CD4+, CD4+ CD25+ CD127low/CD4+ and CD4+CD25highCD127low/CD4+ in PB of AA patients decreased markedly at the active phase (P﹤0.05). By the recovery phase, the percentages of CD4+CD25+/CD4+, CD4+CD25high/CD4+, CD4+ CD25+ CD127low/CD4+ and CD4+CD25highCD127low/CD4+ increased significantly to the levels similar to the controls. There were significant positive relationships between the expression of CD4+CD25highCD127low cells and the quantity of Hb, WBC and Plt (r=0.499, 0.526, 0.540 respectively; P﹤0.05).</p><p><b>CONCLUSIONS</b>The decrease of the percentage of CD4+CD25int/highCD127low regulatory T cells might be associated with the development of pediatric AA. The CD4+CD25int/highCD127low regulatory T cells can serve as a marker for the evaluation of disease severity as well as a target of further study on immune treatment of AA.</p>

Expression of regulatory T cells and Foxp3 gene in peripheral blood of children with aplastic anemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the levels of CD4+CD25+CD127(low) regulatory T cells (Tregs) and the expression of Foxp3 gene in peripheral blood of children with aplastic anemia (AA) and to study their roles in the pathogenesis of AA.</p><p><b>METHODS</b>Twenty-one children with chronic AA, 9 with acute AA and 15 healthy children were enrolled. The proportion of CD4+CD25+ CD127low Tregs in CD4+ T cells was evaluated by flow cytometric analysis. The level of Foxp3 mRNA was ascertained by RT-PCR.</p><p><b>RESULTS</b>The percentage of peripheral blood CD4+T cells and CD4+CD25+ and CD4+CD25+CD127(low) Tregs in CD4+T cells in both the acute and chronic AA groups was significantly lower than that in the normal control group (P<0.05).The acute AA group had more decreased CD4+ T cells and CD4+CD25+ and CD4+CD25+CD127(low) Tregs percentage compared with the CAA group (P<0.05). The expression of Foxp3 mRNA in peripheral blood decreased obviously in the acute AA group (0.47 + or - 0.08%) compared with that in the normal control (0.71 + or - 0.12%) and the CAA groups (0.68 + or - 0.14%) (P<0.05).</p><p><b>CONCLUSIONS</b>The low expression of Tregs and Foxp3 mRNA in peripheral blood may be involved in pathogenesis of AA.The more decreased Tregs and Foxp3 mRNA expression in acute AA than chronic AA suggests their possible roles in the assessment of the severity of AA.</p>

Induction of apoptosis by proteasome inhibitor MG-132 in human erythroleukemia cell line K562 / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate whether proteasome inhibitor MG-132 induces apoptosis of human erythroleukemia cell line K562 and possible mechanisms.</p><p><b>METHODS</b>K562 cells were incubated with RPMI 1640 and exposed to 0, 1, 5, 10, 15 micromol/L of MG-132 for 24 hrs, respectively. The apoptosis of cells were detected by fluorescence microscope, DNA fragments and flow cytometry. The NF-kappaB mRNA expression was quantified by reverse transcription-polymerase chain reaction (RT-PCR). Expression of NF-kappaB and caspase-3 was semiquantitatively analyzed with SABC techniques. Caspase-3 activities were measured with a colorimetric method.</p><p><b>RESULTS</b>The growth of K562 cells was inhibited and the apoptosis of the cells increased after MG-132 treatment in a dose-dependent manner. After 24 hrs of 15 micromol/L MG-132 treatment, the percentage of apoptotic cells (26.5+/-0.6%) increased significantly when compared with the untreated controls (1.2+/-0.1%) (P<0.01). MG-132 treatment decreased the mRNA and protein expression of NF-kappaB, and increased the protein expression of caspase-3.</p><p><b>CONCLUSIONS</b>MG-132 can induce apoptosis of human erythroleukemia cell line K562 through the down-regulation of NF-kappaB expression and up-regulation of caspase-3 expression.</p>

Expression of cyclin A in childhood acute leukemia and its significance / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the expression of cyclin A protein in childhood acute leukemia (AL) and its significance.</p><p><b>METHODS</b>By using Western blotting analysis, cyclin A protein in bone marrow mononuclear cells from 47 newly diagnosed AL children and 33 non-hematological malignancy children was detected.</p><p><b>RESULTS</b>The expression of cyclin A in AL group (0.38 +/- 0.20) was higher than that in control group (0.03 +/- 0.15) (P < 0.01). The expression of cyclin A in high risk acute lymphocyte leukemia (ALL) group (HR-ALL) (0.62 +/- 0.38) was higher than that in standard risk ALL group (SR-ALL) (0.33 +/- 0.33) (P < 0.05). The expression of cyclin A in WBC > or = 50 x 10(9)/L group and in WBC < 50 x 10(9)/L group was (0.64 +/- 0.36) and (0.39 +/- 0.38), respectively (P < 0.05). Eight (44.4%) out of 18 patients with positive cyclin A expression achieved complete remission (CR). The CR rate was lower than that of patients with negative cyclin A expression (100%) (P < 0.01).</p><p><b>CONCLUSIONS</b>The higher expression of cyclin A may predict a poor prognosis for childhood ALL.</p>

Relationship of Janus Kinase-Signal Transducers and Activator of Transcription Signal Transduction and Neurogenesis in Neonatal Rats with Periventricular Leukomalacia / 实用儿科临床杂志

Objective To observe the relationship of the Janus kinase-signal transducers and activator of transcription pathway and neurogenesis in the lateral ventricle subventricular zone(SVZ) and choroid plexus of neonatal rats with periventricular leukomalacia(PVL).Methods PVL models were established by right common carotid artery ligation followed by 4 h 60 mL/L oxygen exposure in 2-day-rat;the neonatal rats performed a sham operation,without hypoxia-ischemia were used as control group.The rats were sacrificed at 0 h,3 h,6 h,12 h,1 d,3 d and 7 d after hypoxic-ischemic(HI),and brain tissues were collected,immunohistochemistry was used to detect the expression of P-STAT3 and Nestin in the subventricular zone and choroid plexus.Results Very low expressions of P-STAT3 and Nestin were observed in lateral ventricle SVZ and choroid plexus in control group.The expression levels of P-STAT3 and Nestin increased significantly after HI,peaked at 1 d and 3 d separately,and remained at a higher level at 7 d after HI,demonstrating significant differences at each time point compared with those in control group(Pa