Tumefactive Demyelination Lesions: Report on three cases.

PURPOSE: Tumefactive demyelination (TD) lesion and its subtype Balo's concentric sclerosis (BCS), are rare manifestations of central nervous system demyelinating disease. Because of its rarity, physicians might hesitate in reaching a diagnosis or initiating steroid pulse therapy. This study aims at pinpointing the key neuroimaging features to distinguish TD lesions from surgical conditions, and illustrating the clinical outcomes of patients with TD lesions. CASE REPORT: Two of the three patients had solitary TD lesions, one 47-year-old man presenting with newly onset seizure and another 54-year-old women suffering from progressive hemiparesis. The male patient underwent craniotomy for mass excision without further steroid therapy, while the female patient received methylprednisolone pulse therapy only. Both patients remained free of clinical and radiological relapses over the past 6-7 years, leading to the diagnosis of clinically isolated syndrome. The third case is a 30-year-old woman with subacute onset of dysarthria and hemiparesis. She had two BCS lesions along with other demyelinating lesions in the juxtacortical and periventricular regions, cerebellar peduncles, and spinal cord, fulfilling dissemination in time and space. Her neurological deficits resolved after pulse therapy, and she received long-term disease modifying therapy for multiple sclerosis. CONCLUSION: This study underscores the diverse neuroimaging and clinical presentations of patients with TD lesions, and emphasizes the importance of clinical vigilance regarding this rare condition.

Nitrogen allocation for CO2 fixation promotes nitrogen use in the photosynthetic compensation of soybean under heterogeneous light after a pre-shading.

The spatial and temporal distribution of sunlight around plants is constantly changing in natural and farmland environments. Previous studies showed that the photosynthesis of crops responds significantly to heterogeneous light conditions in fields. However, the underlying mechanisms remain unclear. In the present study, soybean plants were treated by heterogeneous light after a pre-shading (SH-HL) to simulate the light condition in relay strip intercropping. Gas exchange and nitrogen (N) of leaves were measured to evaluate the photosynthetic performance, as well as photosynthetic N- and water-use efficiency (PNUE and PWUE). Chlorophylls (Chl) and Rubisco were analyzed as representative photosynthetic N components. Results suggest that SH-HL treated soybean exhibited evident photosynthetic compensation as the net photosynthetic rate (Pn) increased significantly in unshaded leaves, from which the export of photosynthates was enhanced. Under SH-HL, leaf N concentration remained relatively stable in unshaded leaves. While Chl concentration decreased but Rubisco concentration increased in unshaded leaves, indicating preferential allocation of leaf N for CO2 fixation. Results also showed that PNUE increased and PWUE decreased in unshaded leaves under SH-HL. Therefore, we suggest that within-leaf N allocation for CO2 fixation in unshaded leaves rather than within-plant N distribution to unshaded leaves drives the photosynthetic compensation under heterogeneous light after a pre-shading. However, enhanced water loss from unshaded leaves is a cost for efficient N-use under these conditions. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01392-8.

[Safety and short-term effectiveness of blinatumomab in the treatment of childhood relapsed/refractory acute lymphoblastic leukemia]. / 贝林妥欧单抗治疗儿童复发/éš¾æ²»æ€¥æ€§æ·‹å·´ç»†èƒžç™½è¡€ç— çš„å®‰å ¨æ€§åŠè¿‘æœŸç–—æ•ˆåˆ†æž.

OBJECTIVES: To study the safety and short-term effectiveness of blinatumomab in the treatment of childhood relapsed/refractory acute lymphoblastic leukemia (R/R-ALL). METHODS: Six children with R/R-ALL who received blinatumomab treatment from August 2021 to August 2022 were included as subjects, and a retrospective analysis was performed for their clinical data. RESULTS: Among the six children, there were three boys and three girls, with a median age of 10.5 (5.0-13.0) years at the time of inclusion. Of all six children, one had refractory ALL and did not achieve remission after several times of chemotherapy, and 5 relapsed for the first time, with a median time of 30 (9-60) months from diagnosis to relapse. Minimal residual disease (MRD) before treatment was 15.50% (0.08%-78.30%). Three children achieved complete remission after treatment, among whom two had negative conversion of MRD. Five children had cytokine release syndrome (CRS), among whom 3 had grade 1 CRS and 2 had grade 2 CRS. Four children were bridged to allogeneic hematopoietic stem cell transplantation, with a median interval of 50 (40-70) days from blinatumomab treatment to transplantation. The six children were followed up for a median time of 170 days, and the results showed an overall survival rate of 41.7% (95%CI: 5.6%-76.7%) and a median survival time of 126 (95%CI: 53-199) days. CONCLUSIONS: Blinatumomab has good short-term safety and effectiveness in the treatment of childhood R/R-ALL, and its long-term effectiveness needs to be confirmed by studies with a larger sample size.

[Clinical features and prognosis of juvenile myelomonocytic leukemia: an analysis of 63 cases]. / 63ä¾‹å¹¼å¹´åž‹ç²’å•æ ¸ç»†èƒžç™½è¡€ç— çš„ä¸´åºŠç‰¹å¾ä¸Žé¢„åŽåˆ†æž.

OBJECTIVES: To investigate the clinical features of juvenile myelomonocytic leukemia (JMML) and their association with prognosis. METHODS: Clinical and prognosis data were collected from the children with JMML who were admitted from January 2008 to December 2016, and the influencing factors for prognosis were analyzed. RESULTS: A total of 63 children with JMML were included, with a median age of onset of 25 months and a male/female ratio of 3.2∶1. JMML genetic testing was performed for 54 children, and PTPN11 mutation was the most common mutation and was observed in 23 children (43%), among whom 19 had PTPN11 mutation alone and 4 had compound PTPN11 mutation, followed by NRAS mutation observed in 14 children (26%), among whom 12 had NRAS mutation alone and 2 had compound NRAS mutation. The 5-year overall survival (OS) rate was only 22%±10% in these children with JMML. Of the 63 children, 13 (21%) underwent hematopoietic stem cell transplantation (HSCT). The HSCT group had a significantly higher 5-year OS rate than the non-HSCT group (46%±14% vs 29%±7%, P<0.05). There was no significant difference in the 5-year OS rate between the children without PTPN11 gene mutation and those with PTPN11 gene mutation (30%±14% vs 27%±10%, P>0.05). The Cox proportional-hazards regression model analysis showed that platelet count <40×109/L at diagnosis was an influencing factor for 5-year OS rate in children with JMML (P<0.05). CONCLUSIONS: The PTPN11 gene was the most common mutant gene in JMML. Platelet count at diagnosis is associated with the prognosis in children with JMML. HSCT can improve the prognosis of children with JMML.

KMT2B promotes the growth of renal cell carcinoma via upregulation of SNHG12 expression and promotion of CEP55 transcription.

BACKGROUND: This study aims to clarify the mechanistic action of long non-coding RNA (lncRNA) SNHG12 in the development of renal cell carcinoma (RCC), which may be associated with promoter methylation modification by KMT2B and the regulation of the E2F1/CEP55 axis. METHODS: TCGA and GEO databases were used to predict the involvement of SNHG12 in RCC. Knockdown of SNHG12/E2F1/CEP55 was performed. Next, SNHG12 expression and other mRNAs were quantified by RT-qPCR. Subsequently, CCK-8 was used to detect cell proliferation. Wound healing assay and Transwell assay were used to detect cell migration and invasion, respectively. The in vitro angiogenesis of human umbilical vein endothelial cells (HUVECs) was explored by matrigel-based capillary-like tube formation assay. ChIP assay was used to detect H3K4me3 in SNHG12 promoter region. The binding of E2F1 to CEP55 promoter region was analyzed with ChIP and dual luciferase reporter assays. RIP assay was used to detect the binding of SNHG12 to E2F1. Finally, the effect of SNHG12 on the tumor formation and angiogenesis of RCC was assessed in nude mouse xenograft model. RESULTS: SNHG12 was highly expressed in RCC tissues and cells, and it was related to the poor prognosis of RCC patients. SNHG12 knockdown significantly inhibited RCC cell proliferation, migration, and invasion and HUVEC angiogenesis. KMT2B up-regulated SNHG12 expression through modifying H3K4me3 in its promoter region. In addition, SNHG12 promoted CEP55 expression by recruiting the transcription factor E2F1. Knockdown of SNHG12 blocked E2F1 recruitment and down-regulated the expression of CEP55, thereby inhibiting tumor formation and angiogenesis in nude mice. CONCLUSION: The evidence provided by our study highlighted the involvement of KMT2B in up-regulation of lncRNA as well as the transcription of CEP55, resulting in the promotion of angiogenesis and growth of RCC.

m6A modification regulates lung fibroblast-to-myofibroblast transition through modulating KCNH6 mRNA translation.

Idiopathic pulmonary fibrosis (IPF) is a chronic, fatal lung disease characterized by progressive and non-reversible abnormal matrix deposition in lung parenchyma. Myofibroblasts originating mainly from resident fibroblasts via fibroblast-to-myofibroblast transition (FMT) are the dominant collagen-producing cells in pulmonary fibrosis. N6-methyladenosine (m6A) modification has been implicated in various biological processes. However, the role of m6A modification in pulmonary fibrosis remains elusive. In this study, we reveal that m6A modification is upregulated in a bleomycin (BLM)-induced pulmonary fibrosis mouse model, FMT-derived myofibroblasts, and IPF patient lung samples. Lowering m6A levels through silencing methyltransferase-like 3 (METTL3) inhibits the FMT process in vitro and in vivo. Mechanistically, KCNH6 is involved in the m6A-regulated FMT process. m6A modification regulates the expression of KCNH6 by modulating its translation in a YTH-domain family 1 (YTHDF1)-dependent manner. Together, our study highlights the critical role of m6A modification in pulmonary fibrosis. Manipulation of m6A modification through targeting METTL3 may become a promising strategy for the treatment of pulmonary fibrosis.

[Clinical features and prognosis of childhood acute myeloid leukemia with myelodysplasia-related changes].

OBJECTIVE: To study the clinical features and prognosis of childhood acute myeloid leukemia with myelodysplasia-related changes (AML-MRC). METHODS: A retrospective analysis was performed on the medical data of 14 children who were diagnosed with AML-MRC from June 2014 to March 2020, including clinical features, laboratory examination results, and prognosis. RESULTS: Among the 14 children with AML-MRC, there were 9 boys and 5 girls, with a median age of 11 years (range: 1-17 years), a median leukocyte count of 8.3×109/L [range: (2.0-191.0)×109/L], a median hemoglobin level of 73 g/L (range: 44-86 g/L), and a median platelet count of 75×109/L [range: (4-213)×109/L] at diagnosis. According to the FAB classification, the children with AML-M5 accounted for 71% (10/14). Among the 14 children, 4 had multi-lineage dysplasia (MLD), 2 had a history of myelodysplastic syndrome (MDS), 5 had MDS-related cytogenetic changes, 2 had MLD with MDS-related cytogenetic changes, and 1 had a history of MDS with MLD. The median follow-up time was 10.6 months (range: 0.4-54.4 months) for 14 children, among whom 2 gave up treatment immediately after diagnosis and 12 had an evaluable treatment outcome. The 2-year overall survival (OS) rate was 50%±15%, and the 2-year disease-free survival (DFS) rate was 33%±13%. Of the 12 children, 7 underwent haploidentical hematopoietic stem cell transplantation (HSCT), among whom 5 achieved DFS and 2 died, with a 2-year OS rate of 71%±17% and a 2-year DFS rate of 43%±19%; 5 children underwent chemotherapy alone, among whom 1 achieved DFS, 3 died, and 1 was lost to follow-up, with a 2-year OS rate of 40%±30% and a 2-year DFS rate of 30%±24%. There was no significant difference in the survival condition between the transplantation and chemotherapy groups (P > 0.05). CONCLUSIONS: Childhood AML-MRC is often observed in boys, and AML-M5 is the most common type based on FAB classification. Such children tend to have a poor prognosis. HSCT is expected to improve the poor prognosis of children with AML-MRC. However due to the small number of cases, it is necessary to increase the number of cases for further observation.

[CD20 is not a poor prognostic factor for childhood B-lineage acute lymphoblastic leukemia with high white blood cell count].

OBJECTIVE: To study the significance of CD20 combined with white blood cell (WBC) count at diagnosis in the prognosis assessment in children with B-lineage acute lymphoblastic leukemia (ALL). METHODS: A retrospective analysis was performed on the medical data of 821 B-ALL children who were treated with CCLG-ALL2008 regimen from April 2008 to April 2015. Their survival status was followed up. RESULTS: Among the 821 children, 547 (66.6%) were negative, while 274 (33.4%) were positive for CD20 expression. Among 694 children with WBC<50×109/L (lower WBC count), the 5-year EFS rates were 65.9%±3.2% and 77.3%±2.0% for CD20 positive and negative patients respectively (P=0.001); the 5-year OS rates were 78.3%±2.9% and 87.5%±1.6% for CD20 positive and negative patients respectively (P=0.005); CD20 positive expression was an independent risk factor for EFS (HR=1.634, P=0.001) and OS (HR=1.761, P=0.005). Among 127 children with WBC>50×109/L (higher WBC count), the 5-year EFS rates was 64.3%±7.7% and 53.7%±5.5% for CD20 positive and negative patients respectively (P=0.135); the 5-year OS rate was 81.4%±6.4% and 58.6%±5.6% for CD20 positive and negative patients respectively (P=0.022); CD20 positive expression was an independent protective factor for OS (HR=0.367, P=0.016). CONCLUSIONS: In children with B-ALL who are treated with CCLG-ALL2008 regimen, those with CD20 positive expression in lower WBC count at diagnosis have a poor prognosis; however, those with CD20 positive expression in higher WBC count at diagnosis have a better long-time survival.

[Clinical effect of two different regimens in treatment of acute lymphoblastic leukemia children with bone marrow recurrence].

OBJECTIVE: To study the short-term effect of two different re-induction regimens in the treatment of acute lymphoblastic leukemia (ALL) children with bone marrow recurrence. METHODS: A retrospective analysis was performed for 57 ALL children with bone marrow recurrence. According to their treatment regimen, they were divided into two groups: VMDP (vincristine + mitoxantrone + dexamethasone + PEG-asparaginase; n=42) and VIDP (vincristine + idarubicin + dexamethasone + PEG-asparaginase; n=15). The two groups were compared in terms of complete response rate and incidence rate of adverse reactions. RESULTS: There was no significant difference in complete response rate between the VMDP and VIDP groups (74% vs 73%, P>0.05). All children experienced grade ≥3 hematological adverse events. The VMDP group had a significantly lower chemotherapy-related mortality rate than the VIDP group (P<0.05). There was no significant difference in the incidence rate of infection between the two groups (P>0.05). CONCLUSIONS: For ALL children with bone marrow recurrence, both re-induction regimens can achieve a relatively high complete response rate, and VMDP regimen has a lower chemotherapy-related mortality rate and can thus be used as an option for re-induction in ALL children with bone marrow recurrence.

[Pharmacokinetics and pharmacodynamics of pegylated recombinant human granulocyte colony-stimulating factor in children with acute lymphoblastic leukemia: a prospective control trial].

OBJECTIVE: To study the pharmacokinetic characteristics, clinical effect, and safety of pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) in children with acute lymphoblastic leukemia (ALL). METHODS: A prospective study was performed on children with ALL who cyclophosphamide, cytarabine, and 6-mercaptopurine were used for consolidation therapy. PEG-rhG-CSF (PEG-rhG-CSF group) or rhG-CSF (rhG-CSF group) was injected after chemotherapy. The plasma concentration of PEG-rhG-CSF was measured, and clinical outcome and safety were observed for both groups. RESULTS: A total of 17 children with ALL were enrolled, with 9 children in the PEG-rhG-CSF group and 8 children in the rhG-CSF group. In the PEG-rhG-CSF group, the peak concentration of PEG-rhG-CSF was 348.2 ng/mL (range 114.7-552.0 ng/mL), the time to peak was 48 hours (range 12-72 hours), and the half life was 14.1 hours (range 11.1-18.1 hours). The plasma concentration curve of PEG-rhG-CSF was consistent with the mechanism of neutrophil-mediated clearance. Compared with the rhG-CSF group, the PEG-rhG-CSF group had a significantly shorter median time to absolute neutrophil count (ANC) recovery (P<0.05). There were no significant differences between the two groups in ANC nadir, incidence rate of febrile neutropenia, duration of grade IV neutropenia, incidence rate of infection, and length of hospital stay. No bone pain or muscle soreness was observed in either group (P>0.05). CONCLUSIONS: The pharmacokinetic characteristics of PEG-rhG-CSF in children with ALL receiving consolidation chemotherapy are consistent with the mechanism of neutrophil-mediated clearance, with a short half life and fast recovery of ANC, and there are no significant differences in safety between PEG-rhG-CSF and rhG-CSF.

[Association of cerebrospinal fluid status with prognosis in children with acute lymphoblastic leukemia].

OBJECTIVE: To study the clinical features of central nervous system infiltration-positive (CNSI+) children with acute lymphoblastic leukemia (ALL) based on flow cytometry, as well as the association of such clinical features with prognosis. METHODS: A retrospective analysis was performed for the clinical data of 66 CNSI+ children with ALL treated from April 2008 to June 2013. Clinical features, laboratory examination results and prognosis were compared between the children in different chemotherapy stages (induction stage and consolidation/maintenance stage). RESULTS: Among the 66 CNSI+ children, 50 were in the induction stage and 16 in the consolidation/maintenance stage. Compared with the CNSI+ children in the induction stage, the CNSI+ children in the consolidation/maintenance stage had a significantly higher proportion of children with the genes associated with good prognosis based on the results of molecular biology (P<0.05), as well as a significantly higher recurrence rate (P<0.05). Recurrence was observed in 21 CNSI+ ALL children, among whom 10 were in the induction stage and 11 were in the consolidation/maintenance stage. Compared with the children experiencing recurrence in the induction stage, the children experiencing recurrence in the consolidation/maintenance stage had a significantly higher proportion of children with recurrence of the central nervous system and bone marrow (P<0.05), as well as significantly higher proportion of biochemical positive rate of cerebrospinal fluid (P<0.05). The children in the induction stage had a significantly higher recurrence-free survival rate than those in the consolidation/maintenance stage (P<0.001), while there was no significant difference in overall survival rate between the two groups (P>0.05). CONCLUSIONS: In children with ALL, CNSI+ has a marked effect on recurrence-free survival rate in different chemotherapy stages, but has no obvious effect on overall survival rate. CNSI+ patients in the consolidation/maintenance stage have a higher recurrence.

Predicting response to porcine antilymphocyte globulin plus cyclosporine A in children with acquired severe aplastic anemia.

BACKGROUND: In severe aplastic anemia (SAA), predictive markers of response to immunosuppressive therapy (IST) of porcine antilymphocyte globulin (pALG) have not been well defined. We investigated whether clinical and laboratory findings before treatment could predict response in a pediatric cohort. METHODS: In this study, we included 70 newly diagnosed SAA children and treated them with pALG. The response rate was documented during follow-up. The log-rank test compared response rates between the potential predictive factors. RESULTS: The response rate was 57.1% at 24 months follow-up. In log-rank test, mild disease severity was the most significant predictive marker of better response (P < 0.001); SAA patients with higher absolute reticulocyte count (ARC) and platelet level showed a higher response rate (both P < 0.001). Although insignificantly, elderly children and male sex show better response rate after treatment. The response rate worsened when the time interval before IST was more than 60 days. CONCLUSION: Modified IST with pALG was suitable for SAA children, and favorable response correlates with mild disease severity was identified. ARC and platelet status also appeared to be a reproducible prognostic model for response rate. IST should be started as soon as possible, given that the response rate worsens as the interval between diagnosis and treatment increases.

[Long-term clinical effect of the CCLG-ALL2008 regimen in treatment of childhood acute lymphoblastic leukemia with different molecular biological features].

OBJECTIVE: To study the long-term clinical effect of the CCLG-ALL2008 regimen in the treatment of children newly diagnosed with acute lymphoblastic leukemia (ALL) with different molecular biological features. METHODS: A total of 940 children who were newly diagnosed with ALL were enrolled in this study. The children were treated with the CCLG-ALL2008 regimen. A retrospective analysis was performed for the long-term outcome of ALL children with different molecular biological features. RESULTS: Among the 940 children with ALL, there were 570 boys and 370 girls, with a median age of onset of 5 years (range 1-15 years) and a median follow-up time of 65 months (range 3-123 months). The complete response (CR) rate was 96.7%, the predicted 10-year overall survival (OS) rate was 76.5%±1.5%, and the event-free survival (EFS) rate was 62.6%±3.0%. After CR was achieved after treatment, the overall recurrence rate was 21.9%. The children with positive ETV6-RUNX1 had the lowest recurrence rate and were prone to late recurrence, and those with positive MLL rearrangement had the highest recurrence rate and were prone to early recurrence. The children with positive ETV6-RUNX1 had a significantly higher predicted 10-year OS rate than those with positive TCF3-PBX1, BCR-ABL, or MLL rearrangement and those without molecular biological features (P<0.05). The children with positive ETV6-RUNX1 had a significantly higher predicted 10-year EFS rate than those with positive BCR-ABL or MLL rearrangement (P<0.05). CONCLUSIONS: Molecular biological features may affect the long-term prognosis of children with ALL, and positive MLL rearrangement and BCR-ABL fusion gene are indicators of poor prognosis. Children with positive ETV6-RUNX1 fusion gene have the highest long-term survival rate.

[Mitoxantrone-cytarabine-etoposide induction therapy in children with acute myeloid leukemia: a single-center study of complications and clinical outcomes].

OBJECTIVE: To investigate the complications and clinical outcome of children with acute myeloid leukemia (AML) undergoing mitoxantrone-cytarabine-etoposide (MAE) induction therapy. METHODS: A total of 170 children with AML were given MAE induction therapy, and the complications and remission rate were analyzed after treatment. RESULTS: The male/female ratio was 1.33:1 and the mean age was 7.4 years (range 1-15 years). Leukocyte count at diagnosis was 29.52×109/L [range (0.77-351)×109/L]. Of all children, 2 had M0-AML, 24 had M2-AML, 2 had M4-AML, 48 had M5-AML, 3 had M6-AML, 7 had M7-AML, 69 had AML with t(8;21)(q22;q22), and 15 had AML with inv(16)(p13.1q22) or t(16;16)(p13.1;q22). The most common complication was infection (158/170, 92.9%). Among these 158 patients, 22 (13.9%) had agranulocytosis with pyrexia (with no definite focus of infection), and 136 (86.1%) had definite focus of infection (including bloodstream infection). Other complications included non-infectious diarrhea, bleeding, and drug-induced hepatitis. Treatment-related mortality was observed in 10 children, among whom 8 had severe infection, 1 had multiple organ failure, and 1 had respiratory failure. Remission rate was evaluated for 156 children and the results showed a complete remission rate of 85.3%, a partial remission rate of 4.5%, and a non-remission rate of 10.3%. CONCLUSIONS: Induction therapy with the MAE regimen helps to achieve a good remission rate in children with AML after one course of treatment. Infection is the main complication and a major cause of treatment-related mortality.

[Clinical features and prognosis of children with acute lymphoblastic leukemia and different platelet levels].

OBJECTIVE: To study the association of platelet level at diagnosis with prognosis in children with acute lymphoblastic leukemia (ALL). METHODS: A total of 892 children with ALL who underwent chemotherapy with the CCLG-ALL 2008 regimen were enrolled. According to the platelet count at diagnosis, these children were divided into normal platelet count group (platelet count ≥100×109/L; n=263) and thrombocytopenia group (platelet count <100×109/L; n=629). The thrombocytopenia group was further divided into (50- <100)×109/L (n=243), (20- <50)×109/L (n=263), and <20×109/L (n=123) subgroups. The association of clinical features (sex, age, immunophenotype, and molecular biology) with event-free survival (EFS) and overall survival (OS) was analyzed. RESULTS: Compared with the thrombocytopenia group, the normal platelet count group had significantly lower positive rate of MLL gene rearrangement and recurrence rate (P<0.05), as well as a significantly higher 10-year EFS rate (P<0.05). There was no significant difference in 10-year OS between the two groups (P>0.05). The normal platelet count group still had a significantly higher 10-year EFS rate than the thrombocytopenia group after the children with MLL gene rearrangement were excluded (P<0.05), and there was still no significant difference in 10-year OS between the two groups (P>0.05). The <20×109/L subgroup had significantly lower 10-year EFS and OS rates than the normal platelet count group, the (50- <100)×109/L subgroup, and the (20- <50)×109/L subgroup (P<0.05). After the children with MLL gene rearrangement were excluded, the <20×109/L subgroup still had significantly lower 10-year EFS and OS rates than the normal platelet count group, the (50-<100)×109/L subgroup, and the (20- <50)×109/L subgroup (P<0.05). CONCLUSIONS: ALL children with MLL gene rearrangement often have the clinical manifestation of thrombocytopenia. Platelet level at diagnosis is associated with the prognosis of ALL children. The children with normal platelet count have a low recurrence rate and good prognosis, and those with a platelet count of <20×109/L have the worst prognosis.

[Clinical characteristics of clonal evolution after immunosuppressive therapy in children with severe/very severe aplastic anemia].

OBJECTIVE: To evaluate the clinical characteristics and risk factors of clonal evolution after immunosuppressive therapy (IST) in children with severe/very severe aplastic anemia (SAA/VSAA). METHODS: The clinical data of 231 children with newly-diagnosed SAA/VSAA who received IST were retrospectively studied. The incidence and risk factors of clonal evolution after IST were analyzed. RESULTS: The 5-year overall survival rate of the 231 patients was 82.7%. Except for 18 cases of early deaths, 213 patients were evaluated for IST efficacy. Among the 231 patients, cytogenetic abnormalities for at least two chromosome metaphase were detectable in 14 (7.4%) patients, and PNH clones were detectable in either peripheral red blood cells or neutrophils for 95 patients. Among the 213 patients evaluated for IST efficacy, 15 patients experienced clonal evolution after IST. Five patients had PNH and trisomy 8 which were defined as favorable progressions, and ten patients experienced monosomy 7 and MDS/AML as unfavorable progressions. The 5-year accumulative incidence of favorable and unfavorable progression were (2.2±2.2)% and (4.8±3.3)%, respectively. Until the last follow-up, 100% (5/5) of patients with favorable progressions and 50% (5/10) of patients with unfavorable progressions survived. WBC>3.5×109/L, CD3+T cell percentage>80%, dosage of antithymocyte globulin >3.0 mg/(kg·d) and no response to IST were related to unfavorable progressions by univariate analysis. Cox multivariate analysis revealed that an increased CD3+T cell percentage (>80%) and no response to IST were independent risk factors for unfavorable progressions. CONCLUSIONS: The children with SAA/VSAA who have an increased CD3+T cell percentage at diagnosis or have no response to IST are in high risks of unfavorable progressions.

The roles of auxin in seed dormancy and germination.

Seed dormancy and germination are attractive topics in the fields of plant molecular biology as they are key stages during plant growth and development. Seed dormancy is intricately regulated by complex networks of phytohormones and numerous key genes, combined with diverse environmental cues. The transition from dormancy to germination is a very important biological process, and extensive studies have demonstrated that phytohormones abscisic acid (ABA) and gibberellin acid (GA) are major determinants. Consequently, the precise balance between ABA and GA can ensure that the seeds remain dormant under stress conditions and germinate at optimal times. Here we review the role of auxin in seed dormancy and germination. Auxin is one of the classic phytohormones effective during tropism growth and tissue differentiation. Recent studies, however, show that auxin possesses positive effects on seed dormancy, which suggests that auxin is the second phytohormone that induces seed dormancy, besides ABA. We will focus on the synthetic effects in detail between auxin and ABA pathways on seed dormancy and propose future research directions.

[Current understanding of signaling transduction pathway and biological functions of Karrikins].

Karrikins are a class of signaling molecules discovered in wildfire smoke, which can significantly promote seed germination in some species (such as Arabidopsis and Avena fatua). The structures of Karrikins were first elucidated in 2004. At present, six different types of Karrikins have been documented, and their biological activities vary significantly. So far, studies for Karrikins have become a hot spot in the plant molecular biology field. Recent advances demonstrate that Karrikins regulate plant photomorphogenesis and leaf differentiation effectively, in addition to the effect on seed germination. Furthermore, Karrikins share highly similar molecular structures and signaling transduction pathways with strigolactone. In this review, we summarize the history of discovery, signaling transduction pathways, physiological functions and ecological significance of Karrikins, and further discuss the future research directions.

[The Optics and Magnetic Properties of Cr Doped ZnO Thin Films].

The precursor solution is sent to the ultrasonic nozzle directly through a needle tube to prepare Zn1-xCrxO (x=0, 0.01, 0.03 and 0.05)films on quartz substratesby ultrasonic spray method. The structures, optical and magnetic properties of the films were measured by X-ray diffracmeter(XRD), scanning electron microscope(SEM), fluorescence spectrometer, ultraviolet-visible light detector, vibrating sample magnetometer (VSM) and so on. The experimental results indicate that, the undopedZnO thin films exhibit the hexagonal wurtzite crystalline structure with a preferential orientation of (002); the Cr doping restrains the preferred orientation of C axis; the average grain sizes of the samples increase withCr doping, and thesize attains the maximum(31.4 nm) when x=3%. The SEMimages show that the Zn1-xCrxO (x=0, 0.01, 0.03 and 0.05) films are grain-like particles. And it exhibits a long strip shape when x=5%. Moreover, the doping of Cr makes the photoluminescence (PL) spectra of Zn1-xCrxO films change evidently. The undoped sample shows an ultraviolet emission peak at 378 nm as well as a defect related green peak at around 550 nm. However, for the doping samples, there is only a wide range of emission peak from 350 to 550 nm. By gaussian fitting，it is found that VZn, Zni and V-Zn defects exist in the Cr doping films, and VZn is largest when x=3%. The band gap increases with the doping of Cr, and reaches the maximum when x=3%. The doping of Cr hasthe band gap of the samples increase, and the band gapreachs themaximum(3.37 eV) when x=3%. Magnetic measured results show that threedoping samples Zn1-xCrxO(x=1%, 3% and 5%) are ferromagnetic at room temperature, and the magnetization of Zn1-xCrxO (x=3%) is the largest, which is corresponding to the most VZn defect. The experimental results also prove the the oretical prediction that the substitutive Cr in the oxidation state of +3 and the neutral Zn vacancy in the ZnO∶Cr sample are the most favorable defect complex to maintain a high stability of ferromagnetic order.

[Effect of P and K Fertilization on Four Iridoids in Axial and Lateral Root of Gentiana crassicaulis].

Objective: To study the effect of phosphorus( P) and potassium( K) fertilization on four iridoids in axial and lateral root of Gentiana crassicaulis. Methods: Field experiment was conducted based on phosphorus and potassium,and the content of four iridoids was analyzed in the axial and lateral root of Gentiana crassicaulis. Results: Despite of different proportion of phosphorus and potassium,the content of four iridoids in axial root was always higher than that in the lateral root, and under normal fertilizer condition, the content of axial and lateral root was 12. 36% and 9. 84%, respectively. On the condition of phosphorus and potassium fertilization, the content of gentiopicroside and loganic acid were higher than that of the swertiamarin and sweroside both in the axial and lateral root. And the difference of the two parts could be increased by high potassium with appropriate phosphorus application. Conclusion: The four iridoids were more likely to accumulate in the axial root of Gentiana crassicaulis, and phosphorus and potassium fertilization, only affected the different degrees on the content of ingredients among two parts. Thus, more attention should be paid to the use of phosphorus and potassium fertilization, and the difference of the active ingredient content in the axial and lateral root of Gentiana crassicaulis.