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The western margin of the Ordos Basin and its adjacent regions have undergone a complex tectonic evolution from the Mesozoic to the Cenozoic era. However, the question of tectonic uplift since the Cenozoic era remains a topic of contention, and the regional thermal evolution history necessitates precise chronological evidence. Situated close to the thrust belt within the western margin of the Ordos Basin, the Niushoushan-Luoshan area holds pivotal significance in unraveling the Mesozoic tectonic events within the basin's confines. Through a meticulous exploration employing apatite fission track (AFT) analysis and thermal history simulation, this study delineates the Mesozoic uplift sequence and its temporal confines in the Niushoushan-Luoshan area. The results reveal that the Mesozoic uplift within this region predominantly occurred during the Middle Jurassic period (170 Ma) to the end of the Early Cretaceous (110 Ma). Furthermore, we observe a slightly earlier onset of uplift in the Luoshan area (170 Ma) compared to the Niushoushan area (160 Ma). This uplift is primarily attributed to the north-eastward extrusion of the Qilian orogenic belt. Combining our findings with existing research, we propose that the Cenozoic uplift in the western margin of the Ordos Basin and its adjacent areas started during the Late Triassic, comprising two distinct phases: the first phase unfolding from the Late Triassic (220 Ma) to the end of the Early Jurassic (185 Ma), and the second phase occurring from the Middle Jurassic (175 Ma) to the end of the Early Cretaceous (110 Ma); the uplift in the Niushoushan-Luoshan area is part of the second phase of uplift along the western margin of the Ordos Basin. The two Cenozoic tectonic uplift phases along the western margin of the Ordos Basin display characteristics of north-to-south and southwest-to-northeast propagation, respectively. It is inferred to be associated with the Late Triassic collision between the North China and South China blocks, as well as the movement of the Lhasa Block converging toward the northeast during the Middle to Late Jurassic.

Under fatigue load, insulated gate bipolar transistor (IGBT) experience structural damage and performance degradation, imparting the reliability of power electronic systems. To address this, the relationship between solder layer fatigue crack length and thermal resistance is derived based on heat transfer theory, firstly. The Darveaux model is used to characterize the evolution law of solder layer cracks in IGBT, and a new IGBT performance degradation model along with a method for estimating its undetermined coefficients is proposed. Then, considering the non-stationary characteristics of actual working conditions, a variable amplitude fatigue load model for IGBT is established using the response surface methodology. The rain flow counting method and linear cumulative damage citation are then employed to assess the extent of IGBT performance degradation. Finally, using a type of IGBT product as an example, power cycling thesis are conducted, and performance degradation modeling and analysis are carried out based on experimental data, verifying the effectiveness of the models and algorithms. [ABSTRACT FROM AUTHOR]

In our present stage, agricultural water right trading is dispersed and the scale is smaller, and the market activity of agricultural water right trading is not in full swing. With the contradiction between supply and demand of water resources becoming increasingly tense, agriculture has necessity to stimulate the decisive role of market in water resources allocation, and further create greater trading space for agriultural water rights. Agricultural water rights involve multi-level management systems, but few studies have analyzed the factors affecting the development of agricultural water rights trading from different dimensions in detail, so it is impossible to systematically promote the development of agricultural water rights trading. Therefore, this paper divides the key factors affecting the development of agricultural water rights trading into three dimensions : macro social economy, middle market players and their mutual relations, and micro trading elements. A qualitative analysis is made of the substantive attributes of each factor index in different dimensions and its impact on the development of agricultural water rights trading, and the macro-support for the development of agricultural water rights trading is found. This paper clarifies the development ideas of agricultural water rights trading market, and then focus on the role of micro-trading elements in the process of water rights trading. From three dimensions, it puts forward suggestions on how to strengthen the agricultural water rights trading policy and promote the construction of rural water system connectivity in multiple ways, clarify the role positioning of government and enterprises, and encourage the synchronous transfer of agricultural water rights trading and land to activate the agricultural water rights trading market so as to improve the agricultural water rights trading market to provide the construction foundation and ideas. [ABSTRACT FROM AUTHOR]

As a traditional mathematical tool in reliability field, the probability theory is not applicable to solve the problem that modern reliability engineering encounters with. Taking the application of the uncertainty theory in degraded data analysis as the entry point, the fundamental axioms, operational rules and statistical methods of the uncertainty theory are expounded, and the reliability modeling guideline based on the brief reliability theory is provided. The methods of degraded data analysis and reliability modeling considering uncertain failure threshold is proposed. The degradation equation is established by adopting the time-varying uncertain normal distribution, and the uncertainty distribution of the failure threshold is constructed according to the expert's knowledge, so as to obtain the margin equation of the product. Finally, the reliability model is deduced based on the measurement equation. The problems of parameter estimation and model verification are solved by using the maximum likelihood estimation method and hypothesis test method of uncertain statistics, respectively. The case study shows that the reliability assessment results will obviously deviate if the uncertainty of failure threshold is not considered. The research indicates that the uncertainty theory is suitable to deal with the uncertainty problems in degradation data analysis and has a broad application prospect. [ABSTRACT FROM AUTHOR]

It is an effective way for natural reserves to enhance self-supportive ability and realize sustainable development by developing ecotourism. Taking the experimental zone of Langxiang Natural Reserve in Heilongjiang Province as research object, the forest sub-compartment as research unit, and spatial pattern of environmental suitability of camping sites as research content, an evaluation index system taking natural environment, geographical security, infrastructure and traffic as project levels was built. Delphi and AHP methods were used to determine index weights. A spatial distribution map of camping environmental suitability in Langxiang Natural Reserve was drawn using the GIS spatial information processing technology based on "3S" measurement and the survey data. The results showed that the highest score for quantification of environmental suitability was 90, while the lowest score was 78, and the average value was 83.66 in the 1067 forest sub-compartments for test. The area of forest sub-compartments which were suitable for camping was 1094.44 hm2, being 12.2% of the experimental zone. The forest sub-compartments which had high environmental suitability in the research area were distributed uniformly and centralized with low degree of fragmentation. It was suggested that the contiguous forest sub-compartments with high scores of environmental suitability could be integrated for camping tourism. Due to the high level of environmental suitability for camping, the experimental zone of Langxiang Natural Reserve is suitable for developing camping tourism. Based on "3S" technology, the land use conditions of ecotourism environment of a natural reserve could be evaluated quickly and quantitatively by mathematical model. [ABSTRACT FROM AUTHOR]

To deal with the uncertainty problem about the logical relationship and time of aircraft support activities, a support process model based on random network is built by analyzing the aircraft support operating process. The support operating time is solved by graphical evaluation and review technique (GERT) , and the solution steps are given. A support process example is studied to demonstrate the effectiveness and applicability of the proposed methodology. According to sensitivity parameter analysis, the corresponding suggestions on aircraft support operations are presented. [ABSTRACT FROM AUTHOR]

It is an effective way for natural reserves to enhance self-supportive ability and realize sustainable development by developing ecotourism. Taking the experimental zone of Langxiang Natural Reserve in Heilongjiang Province as research object, the forest sub-compartment as research unit, and spatial pattern of environmental suitability of camping sites as research content, an evaluation index system taking natural environment, geographical security, infrastructure and traffic as project levels was built. Delphi and AHP methods were used to determine index weights. A spatial distribution map of camping environmental suitability in Langxiang Natural Reserve was drawn using the GIS spatial information processing technology based on "3S" measurement and the survey data. The results showed that the highest score for quantification of environmental suitability was 90, while the lowest score was 78, and the average value was 83.66 in the 1067 forest sub-compartments for test. The area of forest sub-compartments which were suitable for camping was 1094.44 hm2, being 12.2% of the experimental zone. The forest sub-compartments which had high environmental suitability in the research area were distributed uniformly and centralized with low degree of fragmentation. It was suggested that the contiguous forest sub-compartments with high scores of environmental suitability could be integrated for camping tourism. Due to the high level of environmental suitability for camping, the experimental zone of Langxiang Natural Reserve is suitable for developing camping tourism. Based on "3S" technology, the land use conditions of ecotourism environment of a natural reserve could be evaluated quickly and quantitatively by mathematical model.

This study is to investigate the effect of compound B2 on the damage of PC12 cells induced by serum deprivation and to explore its related mechanisms. The binding characteristics of B2 to rat striatum adenosine A2A receptor was studied by radioligand 3H-MSX-2 binding assay. Cell viability was detected by MTT assay. ROS formation was measured after DCFDA fluorescent staining. B2 has affinity to rat adenosine A2A receptor (K1 = 0.37 micromol x L(-1)). B2 remarkably increased PC12 cell survival rate in serum deprivation-induced PC12 cells. The percentage of serum deprivation-induced death of PC12 was 49.6%, and the treatment of B2 (0.1-100 micromol x L(-1)) increased the cell viability to 63.3%, 74.9%, 86.3% and 88.1%, respectively. Adenosine A2A receptor antagonist SCH 58261 could significantly block the protective effect of B2. The cell viability with 0.1 micromol x L(-1) SCH 58261 decreased by 16.1%, 24.0% and 19.8%, in the presence of B2 (0.1-10 micromol x L(-1)). Serum deprivation-induced ROS formation was 3.5 times more than that of control group, and treatment with B2 significantly and dose-dependently inhibited ROS over-formation. The protective effect of B2 may be related with adenosine A2A receptor. Decrease of serum-deprivation induced ROS formation may also be one of the mechanisms.

Objective: To study the role of flow cytometry (FCM) in detection of polymorphic post-transplant lymphoproliferative disorders (PTLD)., Methods and Results: Two patients presented with fever and multiple lymphadenopathy on day 46 and day 50 respectively after successful allogeneic hematopoietic stem cell transplantation (allo-HSCT). The symptoms couldn't be controlled by antibiotics. The polymorphic PTLD was diagnosed based on the elevation of bone marrow EB virus DNA and detection of subsets of light chain restricted B cells and/or plasma cells in peripheral blood (PB) samples. The lymphocyte immunophenotypes from PB and/or bone marrow (BM) samples were serially tested by FCM after lowering the dose of immunosupressive agents and treating with antivirus drugs, anti-CD20 antibodies, and cytotoxic T cell infusion. B cells were undetable in two patient, but monoclonal plasma cells appeared or maintained. One patient died after two weeks. Another patient was still on treatment. B cells and plasms cells couldn't be detected in her PB, but there were monoclonal plasma cells in her BM. FCM have a prominent advantage in detect polymorphic PTLD, since it can effectively recognize different cell groups in blood and identify monoclonal subsets. Besides, the immunophenotype of plasma cells in polymorphic PTLD might be different from that in typical plasma cell myeloma., Conclusion: Polymorphic PTLD can be detected and followed up by FCM. BM is more suitable than PB for monitoing the disease. Besides lymph node biopsy, B cell abnormaliity could be detected in PB in allo-HSCT patients.

Objective: To investigate the gene mutation in a Chinese pedigree and one sporadic case with pachyonychia congenita type I(PC-1), as well as to explore the relationship between the genotype and phenotype., Methods: The whole coding region of the KRT16 and KRT6A genes were amplified by long-range polymerase chain reaction (PCR). Six patients with PC-1 were studied, five of them were from a pedigree and the other one was sporadic. One unaffected member in the pedigree and 100 unrelated healthy individuals were also studied in order to exclude polymorphism. PCR products were directly sequenced to detect the mutation., Results: No mutations in the KRT16 gene were observed. All patients harbored a mutation in the KRT6A gene. All five patients in the pedigree had a mutation at codon 465 (TAC to CAC) which substitutes tyrosine (Y) by histidine (H). In the sporadic patient, codon 171 (AAC) was mutated to GAC, which changes the asparagines (N) to aspartic acid (D). No such mutations were found in the unaffected member of the pedigree and the 100 unrelated controls. The mutation of Y465H is located at the end of 2B and N171D at the beginning of 1A domain of KRT6A, both are hotspots for pathogenic keratin mutations., Conclusion: The mutations Y465H and N171D of the KRT16A gene were detected in the pedigree and the sporadic case respectively. The Y465H mutation was a novel mutation, and the N171D mutation was reported recently.

This study was purposed to analyze the changes of T-cell clonality after induction of peripheral T lymphocytes by autogenous DC and cytokines in the preparation of adoptive immunotherapy for leukemias. The bone marrow and peripheral blood from 21 leukemia patients at remission stage after treatment and subjected to adoptive immunotherapy were collected. Their DCs and T-cells were stimulated with cytokines and then were mixed to activate T-cells. T-cell receptor beta variable region (TCRBV) families were amplified by RT-PCR, and genescan method and sequencing of the PCR products were used to observe the clonality changes of T-cells before and after the induction and cultivation of T-cells. The flow cytometry was used to identify CD3(+), CD4(+), CD8(+), CD3(+)CD56(+) and CD4(+)CD25str(+)FOXP3(+) cells to disclose the ratio change of cytotoxic T lymphocytes (CTL), helper T-cells, regulatory T-cells and NK T-cells before and after induction and cultivation of T-cells. The results showed that in the 21 patients, most of the 24 TCRBV families presented as oligoclonal distribution on genescan, several families were not expressed, and only a few families remained polyclonal. TCRBV24 was found to be oligoclonal in all of the 21 patients. DNA sequence analysis of TCRBV24 revealed a common motif of VAG in CDR3 in 3 cases and a common motif of GGG in CDR3 in 2 cases. In patient 5, both TCRBV 24 and TCRBV8 contained the same motif of GGG in CDR3. The identical motif in these patients may suggest that these T-cells recognize the same antigen. The peripheral lymphocytes demonstrated recovery of clonal profile on genescan from oligoclonal profile and absence of several families before the induction and cultivation to typical polyclonal profile in all TCRBV families after the induction by DC and cytokines for 13 days. After the induction and cultivation, the number of lymphocytes increased to 3.38 +/- 1.20 times. CD3(+), CD4(+), CD8(+), CD3(+)CD56(+) and CD4(+)CD25str(+)FOX P3(+) cells were 71.1 +/- 11.8%, 26.7 +/- 11.4%, 35.7 +/- 12.9%, 3.1 +/- 1.6% and 0.12 +/- 0.1% respectively before the induction and cultivation, and changed to 95.4 +/- 3.2% (p < 0.01), 27.0 +/- 13.1% (p > 0.01), 55.5 +/- 13.8% (p < 0.01), 9.8 +/- 6.1% (p < 0.01) and 0.22 +/- 0.18% (p < 0.01) respectively after the induction and cultivation. It is concluded that the major action of this induction and cultivation method on T-lymphocytes in vitro is the promotion of CTL and NK T-cell proliferation. In leukemic patients at the remission stage, the TCRBV profile is characterized by the oligoclonal proliferation of T-lymphocytes. Several proliferated clones may have the same motif in CDR3, suggesting the recognition of the same antigen by these lymphocyte clones. Cytokine induction and co-culture with autogenous DCs can stimulate the T-lymphocytes to recover their immunocompetence as manifested by the polyclonal profile and the proliferation of CTL and NK-T cells.

Objective: To investigate whether WASP/Verprolin homologous protein 1 (WAVE1) plays a role in the pathogenesis of childhood acute lymphoblastic leukemia (ALL)., Methods: WAVE1 mRNA and protein expression in bone marrow mononuclear cells (BMMCs) was measured by RT-PCR and Western blotting respectively in 4 children with ALL relapse, 15 children with ALL in complete remission (CR) and 40 children with newly diagnosed ALL. Ten normal bone marrow samples were used as controls. Jurkat cells were treated with different concentrations of adriamycin (ADM). The cell proliferation was detected with MTT. The apoptosis rate was measured by flow cytometry. WAVE1 mRNA and protein expression of Jurkat cells treated with ADM was detected by RT-PCR and Western blotting respectively., Results: WAVE1 was not expressed or weakly expressed in BMMCs from normal controls and patients with ALL in CR. Higher WAVE1 mRNA and protein expression was found in BMMCs from patients with newly diagnosed ALL and patients with relapse ALL when compared with the controls and the patients in CR (P<0.01). ADM significantly inhibited the proliferation of the Jurkat cells and the inhibitory effect was dose-and time-dependent (P<0.05). After ADM treatment for 24 hrs, the percentage of apoptosis cells increased significantly and WAVE1 mRNA and protein expression of Jurkat cells decreased significantly when compared with the untreated controls (P<0.05)., Conclusions: The WAVE1 expression increased in children with ALL. WAVE1 may be related to the development of ALL and may be severed as a marker for the evaluation of the severity of ALL in children.

Objective: To investigate the effect of high mobility group boxl (HMGBI) gene silence on adriamycin (ADM)-induced apoptosis in K562/A02 drug resistance leukemia cells., Methods: K562/ A02 cells were transient transfected with HMGB1- small interference RNA(siRNA) vector, and the levels of HMGB1 gene differential expression pre-and post-transfection were measured by RT-PCR and Western blotting. 50% inhibition concentration (IC50) of ADM on K562/A02 was determined by WST-8 assay. Cell apoptosis was assessed by flow cytometry. The release of Smac/DIABLO from the mitochondria to the cytoplasm was assayed by Western blotting. Activity of Caspase-3 was assayed with a Caspase Colorimetric Assay Kit., Results: (1) The HMGB1 expression at mRNA and protein levels in HMGB1 siRNA transfected K562/A02 cells were decreased by 86% and 71% respectively compared with control. (2) Suppression of HMGB1 by siRNA in K562/A02 cells resulted in a reversal of the resistance to ADM, and decreased IC50 from (4.83 +/- 0.08) microg/ml to (1.33 +/- 0.10) microg/ml. 1 microg/ml and 5 microg/ml of ADM treatment increased cell apoptotic rate by 27% and 32% respectively. (3) HMGB1 suppression in K562/A02 cells significantly promoted ADM- induced Smac/DIABLO release from the mitochondria to the cytoplasm, and increased the activities of Caspase-3., Conclusion: HMGB1 gene silence can enhance sensitivity of K562/A02 cells to ADM and reverse cell resistant to ADM.

Objective: To investigate the diagnostic value of heat shock protein 70 (HSP70) in central nervous system infection (CNSI) in children., Methods: The level of HSP70 in the cerebrospinal fluid (CSF) was determined in children with CNSI of different etiology. The concentration of HSP70 was determined in the CSF of 104 children, among them 13 patients had purulent meningitis (PM), 38 patients had acute viral meningitis (VM), 7 patients had tuberculous meningitis (TM), and 46 with no CNSI to serve as controls. The concentration of HSP70 was determined by Western blotting assay. The CSF specimens were also analyzed for the total cellular score (TCS), white blood cell count (WBC), lactate dehydrogenase (LDH), protein content (PC), adenosine deaminase (ADD), glucose, chloride content (Cl(í)), and pressure., Results: The CSF level of HSP70 was significantly higher in the PM, TM and VM groups [76.61+/-27.69, 65.85+/-33.16, 33.65+/-16.93] compared with the control group (23.28+/-19.77) (P<0.05 or P<0.01). The HSP70 concentration was markedly higher in the CSF of patients with PM and TM than patients with VM (both P<0.01). No significant difference was found between PM group and TM group in HSP70 level in CSF (P>0.05). The concentration of HSP70 in the CSF was positively correlated to TCS (r=0.298, P=0.002), WBC (r=0.274, P=0.005), LDH (r=0.322, P=0.001), PC (r=0.629, P<0.001), ADD (r=0.363, P<0.001), and negatively correlated to the glucose (r=-0.443, P<0.001) in CSF. The HSP70 concentration was not correlated to the Cl(í) (r=0.148, P=0.133) and pressure (r=0.001, P=0.993) of CSF., Conclusion: HSP70 is increased in the CSF of patients with CNSI. It may be one of the pathophysiological mechanisms of acute infection of the central nervous system. The level of HSP70 in CSF may be a valuable index in the differential diagnosis of CNSI, and it may be helpful in differentiating PM and TM from VM.

Objective: To investigate if WAVE1 is involved in mult drug-resistance (MDR) of human leukemia cell line K562/A02., Methods: The level of WAVE1 in K562 and K562/A02 cells was assayed by Western blot and RT-PCR; K562 cells and K562/A02 cells were transient transfected with pEFBOS-WAVE1 reconstructed plasmid or specifically siRNA to WAVE1. 50% inhibition concentration (IC50) of doxorubicin on K562/A02 was determined by WST-8 assay. Hoechst33258 staining was used to examine cell morphological changes and to calculate percentage of apoptotic nuclei. The mRNA level of mdrl was assayed by RT-PCR. The Bcl-2 protein was assayed by Western blot., Results: 1. The WAVE1 expression at mRNA and protein level in K562/A02 cells was increased by about 70% and 63% respectively as compared with that in K562 cells. 2. Overexpression of WAVE1 in K562 cells by transient transfection significantly increased the resistance to doxorubicin, and increased IC50 from (0.05 +/- 0.00) microg/ml to (2.99 +/- 0.12) microg/ml, and at 1 microg/ml or 5 microg/ml of doxorubicin treatment, cell apoptotic nuclei rate was decreased by 30% or 35% respectively. 3. Suppression of WAVE1 in K562/A02 cells by siRNA resulted in a reversal of MDR to doxorubicin, and decreased IC50 from (4.29 +/- 0.15) microg/ml to (1.85 +/- 0.07) microg/ml, and at 1 microg/ml or 5 microg/ml of doxorubicin treatment, cell apoptotic nuclei rate was increased by 24% or 21% respectively. 4. Overexpression of WAVE1 in K562 cells significantly increased the mdrl mRNA and the Bcl-2 protein, and suppression of WAVE1 in K562/A02 cells by siRNA decreased the mRNA and the protein., Conclusion: WAVE1 involves in the MDR mechanisms in K562/A02 leukemia cells through regulation the level of mdrl and Bcl-2.

Objective: This study analyzed the clinical data of newly diagnosed childhood leukemia from various hospitals in the cities or counties of Hunan Province between 2002 and 2005 in order to provide references for further epidemiologic survey of childhood leukemia., Methods: The clinical data of children with newly diagnosed leukemia from hospitals of various cities or counties of Hunan Province between 2002 and 2005 were collected and reviewed., Results: There were 803 children with leukemia during 2002-2005. Acute lymphoid leukemia was most commonly seen (597/803, 74.35%), followed by acute non-lymphoid leukemia (192/803, 23.91%) and chronic myelocytic leukemia (14/803, 1.74%). There were no significant differences in the clinical type and the prevalence of leukemia between males and females. The prevalence of newly diagnosed childhood leukemia in the urban area was noticeably higher than that in the rural area (2.02/10(5) vs 1.50/10(5), P < 0.05). 41.79% of children with newly diagnosed leukemia from the urban area received treatments but only 22.80% of patients from the rural area received treatments (P < 0.05)., Conclusions: This study of patients-based hospitals showed some features of the morbidity of childhood leukemia in Hunan Province. It provides references for further epidemiologic investigation of this disease in Hunan Province.

Objective: Cytokine mediated cell immunity is the main mode of anti-tumor immunity in organism, and the disequilibrium of cytokine network is the main cause of tumor cells escaping immunologic surveillance. High mobility group box 1 (HMGB1), a nuclear protein, has recently been identified as an important mediator of local and systemic inflammatory diseases when released into the extracellular milieu. In the present study, the investigators explored the clinical significance of alteration in the serum levels of HMGB1 in childhood acute lymphocytic leukemia (ALL) and the mechanism of HMGB1-induced tumor necrosis factor (TNF)-alpha secretion in leukemic cells., Methods: The serum levels of HMGB1 in healthy children and childhood ALL were assayed by Western blotting. K562 leukemic cells were stimulated with recombinant HMGB1 protein in vitro, and the secretion of TNF-alpha was determined by using ELISA. The effects of HMGB1 on activation of p38, c-Jun amino-terminal kinase (JNK), and extracellular-signal regulated protein kinase (ERK) and mitogen-activated protein kinase (MAPK) in K562 cells were assayed by using Western blotting. The effects of inhibitors specific for the MAPK on HMGB1-induced TNF-alpha secretion were assayed by using ELISA., Results: The serum levels of HMGB1 were significantly higher in ALL initial treatment group (n = 15, 43.78 +/- 4.62 microg/ml) than those in healthy control group (n = 15, 0.60 +/- 0.48 microg/ml, P < 0.01) and ALL complete remission group (n = 15, 0.89 +/- 0.62 microg/ml, P < 0.01). No significant difference was found between the healthy control group and ALL complete remission group in HMGB1 levels (P > 0.05). TNF-alpha started to become detectable at 2 h and was still increasing at 16 h after HMGB1 (1 microg/ml) treatment in K562 cell culture. TNF-alpha was also secreted from K562 cells in a dose-dependent manner after HMGB1 (1 ng/ml-1 microg/ml) exposure. HMGB1 induced the phosphorylation of p38, JNK and ERK in k562 cells. Inhibitors specific for the JNK (SP600125), MEK (PD98059), and p38 MAPK (SB203580), abrogated HMGB1-induced TNF-alpha secretion., Conclusions: The measurement of serum HMGB1 is helpful to evaluate the prognosis of the childhood ALL. HMGB1 stimulates leukemic cells to secrete TNF-alpha through a MAPK-dependent mechanism.

Objective: To locate the cluster region of loss of heterozygosity (LOH) in children with acute lymphoblastic leukemia (ALL), and explore the new tumor suppressor gene., Methods: Allelic loss was analyzed by PCR with 15 microsatellite markers mapping on 6q16.3. The LOH was analyzed by bioinformatics. The relationship between LOH and clinical factors was further analyzed., Results: The frequency of LOH at least at one loci on 6q16.3 was 32.7%. The LOH in relapsed patients was higher than those in not relapsed. The higher frequency of LOH was observed in two regions of D6S1709-D6S1028 and D6S2160-D6S1580 at 6q16.3. GRIK2 may be a candidate of tumor suppressor gene. There are 12 ESTs may carry out new anti-oncogene. Patients with 6q LOH had higher WBC counts (P < 0.01), blast cells percentage (P < 0.01), relapse rate (P < 0.05) and chromosomal aberration (P < 0.05)., Conclusion: D6S1709-D6S1028 and D6S2160-D6S1580 are two regions of minimus deletion on 6q16.3 in which tumor suppressor gene may exist. The LOH on 6q16.3 may be a prognostic index of children with ALL.