Correlation between gut microbiota and behavior symptoms in children with autism spectrum disorder / 中国当代儿科杂志

OBJECTIVE@#To investigate the composition of gut microbiota and its correlation with the severity of behavior symptoms in children with autism spectrum disorder (ASD).@*METHODS@#A total of 30 children with ASD were enrolled as the ASD group, and 20 healthy children matched for age and sex were enrolled as the healthy control group. Related clinical data were analyzed. The V3-V4 hypervariable regions of the bacterial 16S rRNA gene in fecal samples were sequenced. The severity of behavior symptoms in children with ASD was assessed using the autism behavior checklist. The Spearman's correlation analysis was used to investigate the correlation between gut microbiota and the severity of behavior symptoms in children with ASD.@*RESULTS@#There was a significant difference in the composition of gut microbiota between the two groups. Compared with the healthy control group, the ASD group had significant reductions in Shannon index and Shannoneven index (P<0.05), as well as a significant reduction in the percentage of Firmicutes and a significant increase in the percentage of Acidobacteria in feces (P<0.05). In the ASD group, the dominant bacteria were Megamonas, Megasphaera, and Barnesiella, while in the healthy control group, the dominant bacteria were Eubacterium_rectale_group, Ezakiella, and Streptococcus. In the children with ASD, the abundance of Megamonas was positively correlated with the scores of health/physical/behavior and language communication (P<0.05).@*CONCLUSIONS@#The development of ASD and the severity of behavior symptoms are closely associated with the composition of gut microbiota.

Deferoxamine induces apoptosis of K562 cells / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the molecular mechanism of apoptosis of leukemic cells (K562 cells) induced by iron chelating agent deferoxamine (DFO).</p><p><b>METHODS</b>The exponentially growing K562 cells were used (1×10(6)/mL) in this study. The K562 cells were treated with different concentrations of DFO (10, 50 and 100 mmol/L), DFO+FeCl3 (10 μmol/L each) or normal saline (blank control). The cellular labile iron pool was measured with a fluorimetric assay using the metalsensitive probe calcein-AM. The viable count and cell viability were determined by typanblue assay. Cell apoptosis was determined by morphological study and flow cytometry assay. Caspase-3 activity in K562 cells was detected by colorimetry.</p><p><b>RESULTS</b>After DFO treatment, the cellular labile iron pool and the viability of K562 cells were reduced and the cell apoptosis increased in a time- and dose-dependent manner compared with the blank control group. The apoptosis rate of K562 cells in the DFO+FeCl3 treatment group was not significantly different from that in the blank control group. The caspase-3 activity in K562 cells increased significantly 24 hrs after 50 and 100 μmmol DFO treatment when compared with the blank control group (P<0.01). There was a negative correlation between cellular labile iron pool and caspase-3 activity of K562 cells (r=-0.894, P<0.05).</p><p><b>CONCLUSIONS</b>DFO induces apoptosis of leukemic cells possibly through decreasing cellular labile iron pool and increasing caspase-3 activity of the cells.</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>

Experimental Study on Activation of Caspase-3 and Apoptosis of K562 Cell Induced by Iron-Deprivation / 实用儿科临床杂志

Objective To observe the relationship between apoptosis of K562 cell induced by iron-deprivation and activation of Caspase-3.Methods K562 cells were treated with desferrioxamine(DFO) in different dosages were collected at different time points.K562 cells were labelled with Annexin V/PI,and then the rate of apoptosis was measured by flow cytometry;The activation of Caspase-3 were detected by colorimetric method with pAN labelled substrate;The active protein of Caspase-3 were analyzed by Western blot.Results When K562 cells were treated with different concentrations of DFO,the apoptosis rate and the activity of Caspase-3 increases gradually.When K562 cells were incubated with DFO(50 ?mol/L and 100 ?mol/L) 24 h later,the enzymatic activity of Caspase-3 increases dramatically more than that of control group,and the difference was significantly(P0.05).All those effect above can be counteracted by equal mole concentration of FeCl_3.Conclusion Iron-deprivation maybe induce the apoptosis of K562 cell by chelating intracellular iron and activing Caspase-3.