Electrochemically Enabled Selenium Catalytic Synthesis of 2,1-Benzoxazoles from o-Nitrophenylacetylenes.

The study reported an electrochemically mediated method for the preparation of 2,1-benzoxazoles from o-nitrophenylacetylenes. Different from the traditional electrochemical reduction of nitro to nitroso, the nitro group directly underwent a cyclization reaction with the alkyne activated by selenium cation generated by the anodic oxidation of diphenyl diselenide and finally produced the desired products.

The Phylogenetic Relationship of Lamiinae (Coleoptera: Cerambycidae) Using Mitochondrial Genomes.

Lamiinae is the largest subfamily of the Cerambycidae (longhorn beetles), with approximately 21,863 described species. Previous phylogenetic studies of Lamiinae showed that this subfamily was monophyletic, but the relationship between the tribes of Lamiinae is still controversial. Partial molecular data and species morphological characteristics are not sufficient to resolve species phylogenetic studies perfectly. At the same time, the full mitochondrial genome contains more comprehensive genetic data. Benefiting from the development of next-generation sequencing (NGS), mitochondrial genomes can be easily acquired and used as reliable molecular markers to investigate phylogenetic relationships within Cerambycidae. Using NGS technology, we obtained 11 mitochondrial genome sequences of Lamiinae species. Based on this newly generated mitochondrial genome dataset matrix, we reconstructed the phylogeny of Lamiinae. The Bayesian Inference and Maximum Likelihood analyses strongly support the monophyly of four tribes (Lamiini, Batocerini, Mesosini, and Saperdini), whereas the tribe Acanthocinini was identified as paraphyletic. Other mitochondrial structural features were also observed: the start codon in the nad1 gene of all 11 mitochondrial genomes is TTG; 17-22 bp intergenic spacers (IGS) with a 'TACTA' motif were found between trnS2 and nad1. Moreover, two long IGS were found in Mesosa myops and Batocera sp. Tandem repeats were found in the IGS of Batocera sp.

[Effects of Leukapheresis on Hemostatic Function in Patients with Hyperleukocytic Leukemia].

OBJECTIVE: To analyze and compare the effects of leukapheresis on hemostatic function in patients with hyperleukocytic leukemia. METHODS: A total of 139 patients with AML, ALL and CML who underwent leukapheresis from June 2009 to February 2020 and did coagulation test before and after operation were included in this study. The clearance efficiency of each group and the difference among three groups were evaluated, as well as hemostatic function including platelet counts, coagulation indicators, CDSS score and incidence of adverse events. The difference of hemostatic function caused by leukapheresis in different leukemia patients were compared. RESULTS: After leukapheresis, the WBC counts were decreased significantly in the three groups of patients (P<0.001), and the clearance efficiency was highest in ALL patients. However, the platelet counts also were decreased significantly (AML:P＜0.001, ALL: P＜0.001, CML: P＜0.01) in the three groups of patients, particularly for acute leukemia patients with a positive correlation with WBC clearance efficiency(r=0.284). After leukapheresis, fibrinogen decreased, PT and APTT prolonged. For acute leukemia patients, higher CDSS score was related to an elevated incidence of bleeding events (P<0.05). CONCLUSION: Leukapheresis is an effective method to decrease the leukemic burden, but it is necessary to monitor the impact on hemostatic function. It is recommended to assess the CDSS socre for acute leukemia patients, in order to identify the predictive value for bleedings.

Successful application of PD-1 knockdown CLL-1 CAR-T therapy in two AML patients with post-transplant relapse and failure of anti-CD38 CAR-T cell treatment.

Patients with relapsed/refractory acute myeloid leukemia (R/R AML) often show resistance to chemotherapy and have dismal outcomes. Therefore, it is urgent to develop new treatment strategies to address this problem. With tremendous achievement of chimeric antigen receptor T cells (CAR-T) therapy against B-cell malignancies, many efforts have been devoted to developing CAR-T therapy for R/R AML but with limited success, in part owing to a lack of specific targets. C-type lectin-like molecule-1 (CLL-1) is highly expressed on AML blasts with no expression on normal hematopoietic stem cells, which makes it an ideal target of immunotherapy for AML. Here, we report 2 R/R AML patients who relapsed after allogeneic stem cell transplantation and failed multiline salvage therapies including anti-CD38 CAR-T therapy, but were successfully treated with PD-1 silenced anti-CLL-1 CAR-T therapy. Both patients achieved molecular complete remission with incomplete hematologic recovery at 28 days of evaluation after CLL-1 CAR-T cell infusion. Cytokine release syndrome in cases 1 and 2 were grade 1 and 2, respectively. At the last follow-up, cases 1 and 2 had maintained continuous remission for 8 and 3 months, respectively. Our results demonstrated that CLL-1 CAR-T cells might be an effective and safe salvage therapy for AML patients with posttransplant relapse.

[Genetic diagnosis of a patient with non-syndromic variants of congenital neutropenia].

OBJECTIVE: To explore the procedures and methods for genetic diagnosis in one non-syndromic variants of congenital neutropenia (NSVCN) patient and its pathogenic mutation. METHODS: Genomic DNA was prepared from one NSVCN patient who had progressed to chronic myelomonocytic leukemia and ELA2, HAX1, WASp and GFI1 genes were amplified and sequenced. RESULTS: A novel compound heterogeneous mutation consisting of two frame-shift mutations (c. 430-1insG and c. 655-9del5bp) was found in HAX1 gene. CONCLUSION: A practically genetic diagnosis procedure for NSVCN has been established, and the novel HAX1 gene mutation may contribute to the etiology of NSVCN.

[Actions of keratinocyte growth factor in leukemic mice allogeneic umbilical cord blood cell transplantation].

OBJECTIVE: To explore the actions of keratinocyte growth factor (KGF) in leukemic mice allogeneic umbilical cord blood cell transplantation (UCBT) and elucidate its mechanism. METHODS: Peripheral blood drawn from the litters of C57BL/6 females was used as umbilical cord blood (UCB) graft. BALB/c mice were randomly divided into 7 groups (n = 12 each). The grouping was as follows. Control group 1, inoculated with leukemia. Control group 2, inoculated with leukemia at -4 d and total body irradiation (TBI) treatment. Control group 3, TBI treatment and reconstituted with 2 × 10(6) UCB-TNCs. Control group 4, injected with PBS subcutaneously, TBI treatment and reconstituted with UCB-TNCs with platelet transfusion. Control group 5, inoculated with leukemia, injected with PBS subcutaneously, TBI treatment and reconstituted with UCB-TNCs with platelet transfusion. Experiment group 1, injected with KGF subcutaneously, TBI treatment and reconstituted with UCB-TNCs with platelet transfusion. Experiment group 2, inoculated with leukemia, injected with KGF subcutaneously, TBI treatment and reconstituted with UCB-TNCs with platelet transfusion. The survival status, pathohistological changes, splenic lymphoid cell subsets and thymic output post-UCBT were compared between groups. RESULTS: The survival time of control group 1 was (11.1 ± 1.5) days and all died of leukemia. The survival time of control group 2 was (11.5 ± 2.5) days and all died of aplasia. Five of 12 mice of control group 3 survived for 100 days and 7 mice died of visceral hemorrhage. Four of 12 mice of control group 5 survived for 100 days and 8 mice died of leukemia with a survival rate of 33.3%. Nine of 12 mice of experiment group 2 survived for 100 days and 3 mice died of leukemia with a survival rate of 75.0%. The survival was prolonged in experiment group 2 mice as compared with that of control group 5 mice (χ² = 4.996, P = 0.0254). The splenic T, NK and B cell counts in control group 4 mice at +35 d were (9.32 ± 0.48) × 106, (1.59 ± 0.11) × 106 and (18.74 ± 2.01) × 106 respectively. While in group 6 mice at +35 d were (13.20 ± 1.14) × 106, (1.75 ± 0.12) × 106 and (20.36 ± 0.86) × 106 respectively. The counts of T cell and NK cell of group 6 were higher than those of group 4 (both P < 0.05). The level of signal joint T-Cell receptor excision circles (sjTRECs) in control group 4 mice was (167 ± 17) copies per 105 cells while that of experiment group 1 mice (228 ± 24) copies per 105 cells. They were higher than that of control mice (P = 0.002). CONCLUSION: Hematopoietic stem/precursor cells are abundant in full-term murine fetal peripheral blood. The infusion of KGF reduces the post-UCBT relapse of leukemia through the enhancement of thymic output.

A taurine-functionalized 3D graphene-based foam for electrochemical determination of hydrogen peroxide.

We present a synthesis approach of taurine-functionalized graphene foam (a-NSGF) using hydrothermal reduction, freeze-drying and high temperature annealing. The higher temperature in annealing allowed the N/S atoms of taurine enter into the graphene lattice, which improves its electrocatalytic activity greatly. The a-NSGF consisting of taurine that modified into 3D layers of graphene and endow is of the rapid sensitive to hydrogen peroxide (H2O2). The electrode using a-NSGF modification reveals highly sensitive and stable towards the concentration change of H2O2 due to the stable 3D structure and good electrical conductivity of a-NSGF. A linear correlation between H2O2 concentration and the electrochemical signal is found to be in a range from 1.5 to 300 µM and the correlation coefficient is R2 = 0.999. The modified electrode has been applied in the determination of H2O2 in rain samples and the results have been compared with the China National Standard Method. The recoveries range from 94.6% to 106.7%. These results show that the proposed sensor is promising for the development of novel electrochemical sensing for H2O2 determination.

Antishock Characteristics of Erythrocyte-mediated Endoplasmic Reticulum Stress in Macrophages in Severe Hemorrhagic Shock Environment Based on TLR9-cGAS-STING-IFN Signal Axis.

This study aimed to investigate the protective effects of erythrocyte-mediated endoplasmic reticulum (ER) stress in macrophages in hemorrhagic shock. An hemorrhagic shock model was established in male BALB/c mice. Animals were randomly divided into three groups (n = 8): control group (A), erythrocyte reinfusion group (B), and TLR9 inhibition group (C). Eight healthy BALB/c mice were also included as group N (n = 8). Mice in group A were not treated, while mice in groups B and C were transfused with red blood cells separated from the blood of mice in group N. Flow cytometry was used to detect the expression of erythrocyte surface protein TLR9 in each group. Immunofluorescence assay was used to analyze the distribution and relative expression of protein STING in macrophages. Flow cytometry was used to analyze the expression of STING, ATF6, and IRE1 in macrophages. Enzyme-linked immunosorbent assay was used to analyze the levels of inflammatory signal molecules, including IFN-α, IFN-ß, IL-6, CCL4, CCL5, and IL-6. FITC-Annexin V was used to analyze the apoptosis of immune cells (macrophages) in mouse blood samples and to detect the concentration of calcium ions in erythrocyte cytoplasm. The results showed that the expression of erythrocyte surface protein TLR9; the distribution of STING-positive cells in macrophages; the expressions of STING, ATF6, and IRE1 in macrophages; the levels of inflammatory signal molecules; the apoptosis rate of macrophages; and the intracellular calcium concentration in erythrocytes in group B were higher than those in group A, followed by group C. These results suggest that TLR9 regulates ER stress in macrophages of mice with hemorrhagic shock through the TLR9-cGAS-STING-IFN signaling pathway. Increased expression of TLR9 enhanced macrophage activity, reduced apoptosis, enhanced inflammatory response and immune response, and restored electrolyte level, which might be a therapeutic option for the treatment of hemorrhagic shock.

[Detection of JAK2V617F mutation and its clinical significance in 80 patients with M2 acute myelogenous leukemia].

OBJECTIVE: To explore the prevalence and prognostic significance of JAK2V617F gene mutation in acute myelogenous leukemia M2 (AML-M2) patients. METHODS: Allele specific polymerase chain reaction (PCR) was used to detect JAK2 gene mutation. RESULTS: Of 80 de novo AML-M2 patients, 6 at the time of first diagnosis and 1 at relapse were found to have JAK2V617F gene mutation (8.8%, 7/80). Morphologically, the whole blood and bone marrow of the 7 AML-M2 patients with JAK2V617F gene mutation presented a picture of acute leukemia instead of myeloproliferative disorders. Immunophenotypically, bone marrow samples showed myelogenous linage expression. Complete remission was obtained in 4 of 5 AML-M2 patients with JAK2V617F mutation who received treatment, while one patient had no response to the treatment. Follow-up was performed in all the 5 patients, with a median survival of 18.5 months in 4 patients. CONCLUSION: JAK2V617F gene mutation, as a type-1 mutation, might not be an initial event in the pathogenesis of acute myelogenous leukemia, and its presentation does not mean a poor prognosis in de novo AML patients.

[Detection and clinical significance of JAK2 mutation in 412 patients with chronic myeloproliferative neoplasms].

OBJECTIVE: To investigate the frequency of JAK2V617F mutation in Chinese patients with chronic myeloproliferative neoplasms (MPN) and to study the relationship between JAK2V617F mutation and clinical characteristics. METHODS: JAK2V617F mutation was screened by allele-specific polymerase chain reaction (AS-PCR). RESULTS: JAK2V617F mutation was detected in 277 of the 412 patients with MPN. The frequency of JAK2V617F mutation was similar among essential thrombocythemia (ET), idiopathic myelofibrosis (IMF) and chronic myeloproliferative disorders-unclassified (MPD-U) (P > 0.05), but it was significantly lower than that in polycythemia vera (PV) (P < 0.05). The presence of JAK2V617F was found to be significantly correlative with advanced age at diagnosis (P < 0.01) and with higher hemoglobin levels and higher leukocyte counts (P < 0.05). Significant difference was found in complication of vascular events between JAK2V617 positive and negative patients (P < 0.05). JAK2V617F positive MPD-U patients were more prone to progress into typical MPN compared with JAK2V617F negative MPD-U patients. The association between abnormal karyotype and JAK2V617F was not found in cytogenetical analysis of 301 patients. CONCLUSION: The presence of JAK2V617F in MPD-U is associated with the disease development. There is a correlation between JAK2V617F mutation in MPN and advanced age, higher leukocyte counts, hemoglobin level and vascular events.

[The quantitative assay and clinical significance of JAK2V617F mutation in 131 patients with chronic myeloproliferative disorders].

OBJECTIVE: To investigate the frequency and mutational status of JAK2V617F mutation in Chinese patients with chronic myeloproliferative disorders (CMPD) and to study the relative quantification of mutated JAK2 mRNA and the clinical significance. METHODS: JAK2V617F mutation and the mutational status were screened with amplification-refractory mutation system polymerase chain reaction (ARMS-PCR), the relative quantification of mutated JAK2 mRNA was studied by using capillary electrophoresis. RESULTS: A higher prevalence of JAK2V617F in either the heterozygote or homozygote status in essential thrombocythemia (ET) was observed in elderly patients with ET (P < 0.05). The presence of JAK2V617F was found to be significantly correlated with the age at diagnosis (P < 0.05); patients with age > or = 60 years showed significantly higher JAK2 mutated RNA levels than those with age < 60 years (P < 0.05); the presence of JAK2V617F in polycythemia vera (PV) and ET was found to be significantly associated with higher hemoglobin level and higher leukocyte count (P < 0.05). In addition, higher leukocyte count was observed in homozygous ET patients than in heterozygous ET patients (P < 0.05). The frequency of JAK2V617F mutation and the prevalence of homozygote in PV patients were higher than those in ET patients (P < 0.05). The differences of JAK2V617F mRNA levels among PV, ET and chronic idiopathic myelofibrosis (IMF) were not significant. CONCLUSIONS: ARMS-PCR technique can be used to detect the frequency and mutational status of JAK2V617F mutation owing to its sensitivity and along with capillary electrophoresis, quantitative assay for mutated JAK2 mRNA, diagnosis of CMPD and judgement of prognosis become possible.

[A study of T-cell reconstitution after HLA-matched sibling bone marrow transplantation in leukemia patients].

OBJECTIVE: To study T-cell reconstitution by the assessment of T-cell receptor excision circle (TRECs) and T-cell receptor clonal repertoire after HLA-matched sibling bone marrow transplantation (MSD-BMT) in leukemia patients and try to reveal the rule of T-cells repopulation in MSD-BMT. METHODS: Real-time quantitative PCR detection of TRECs was carried out in the DNA of peripheral blood mononuclear cells from 23 leukemia patients who underwent MSD-BMT. The content of TRECs in 70 normal donor individuals was also detected to determine the normal range of TRECs in healthy subjects. Among them, 10 patients received RT-PCR to amplify 24 subfamily genes of T-cell receptor B variable (TCRBV) and five normal donors served as control. The PCR products were further analyzed with genescan to evaluate the clonality of BV subfamily and calculate the usage rate of BV families. RESULTS: The mean value of TRECs in normal donors was (3351.1 +/- 3711.1) copies/10(5) cells. There was an inverse correlation between the value of TRECs and the age of healthy subjects. Before transplantation, all the patients were detected for the number of TRECs, the mean TRECs number was (307.9 +/- 433.3) copies/10(5) cells and it was far lower than that of healthy subjects. From one month to five months after bone marrow transplantative (BMT), the TRECs levels were low and in some patients they even could not be detected. Six months later, TRECs levels increased obviously and maintained that high nearly one year. 24 months after BMT, the number of TRECs increased and reached the pretransplantation status. One patient was detected 2 m and 3 m after transplantation and found that there was a tendency of additional use of BV families and an increase of the expression of CDR3 polymorphism. 2-15 months after transplantation, in ten of the patients, there were 7-16 BV subfamilies expressing and in more than 48% the expression was polyclinic. Monoclones and oligoclones existed in 24 BV subfamilies. CONCLUSIONS: At an early stage after BMT, the number of TRECs was low and remained so for a long time. TCRBV CDR3 repertoire showed certain BV families expressing. 6 months after BMT, thymus produced certain number of naive T cells and TCRBV CDR3 repertoire showed additional use of BV families and increased expression of polymorphism.

[Prediction of T-cell immune reconstitution by investigating T cell receptor excision circle and T-cell receptor beta-chain variable region clonal repertoire in leukemia patients after allogeneic hematopoietic stem cell transplantation].

OBJECTIVE: To predict T-cell immune reconstitution by investigating T cell receptor excision circles (TREC) and T-cell receptor beta-chain variable region (TCRBV) clonal repertoire in leukemia patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: Real-time quantitative PCR was used to detect the TREC in 43 leukemia patients undergoing matched sibling donor bone marrow transplantation (MSD BMT), matched unrelated donor (MUD) BMT, or haploidentical-stem cell transplantation (HID-SCT), and in 70 normal individuals. RT-PCR was used to amplify 24 subfamily genes of T-cell receptor beta-chain variable region (TCRBV) in 24 of the 43 patients and 5 normal donors as control. The PCR products were further analyzed by genescane to evaluate the clonality of BV subfamily, characteristics of complementarity determining region 3 (CDR3), and the usage rate in BV subfamily. RESULTS: There were (335.1 +/- 782.5) copies/10(5) cells in the 43 patients before transplantation, far lower than the normal value. The TREC values of the patients of the 3 groups all decreased obviously 3 months after transplantation. The TREC value of the MSD-BMT group recovered faster than the other two groups and reached the value before transplantation in 24 months. The recovery of TREC value in the HID-BMT group was delayed. 3 - 19 months after transplantation, the usage of TCRBV subfamilies was still restricted. There were 6 - 16 BV subfamilies expressed and 33% - 48% of them were polyclonals, the others were monoclones and oligoclones and existed in 24 BV subfamilies, no common monoclone BV subfamilies was expressed. CONCLUSION: Investigation of the TREC and TCRBV clonal repertoire showed that the number of naive T cell is lower and the usage of TCRBV subfamilies skewed 3 - 24 months after allo-HSCT. The immune deficiency of the patients undergoing HID-BMT is more prominent and consistent with the clinical process.

Comparison of SPE, IFE, and FLC in Monitoring Patients with Multiple Myeloma After Autologous Stem Cell Transplantation.

Conventionally, serum protein electrophoresis (SPE) and serum immunofixation electrophoresis (IFE) are used as primary methods to diagnose and monitor multiple myeloma (MM). Recently, serum-free light chain (FLC) assay has been incorporated into hematological screening programs for myeloma. The purpose of this study is to compare the performance of the three methods in monitoring MM patients after autologous stem cell transplantation (ASCT). SPE, serum IFE and serum FLC assay were performed on 38 MM patients who underwent ASCT. In total, four patients had unexpected protein bands (UPBs) and 13 patients had relapsed after ASCT. Our results indicate that IFE is more sensitive than SPE and FLC assay in detection of UPBs and relapse. The results of IFE may provide useful information in advance of patient relapse.

[Influence of HLA-E polymorphism on cytomegalovirus infection after HLA-matched hematopoietic stem cell transplantation].

This study was aimed to explore the potential association of HLA-E polymorphism with the incidence of cytomegalovirus (CMV) infection after HLA-matched hematopoietic stem cell transplantation, 119 HLA-genoidentical sibling pairs for HLA-E polymorphism were analyzed, HLA-E DNA was amplified by polymerase chain reaction (PCR), and the amplified DNA products was also sequenced directly after purification to confirm the genotype. The results showed that the homozygous HLA-E*0101/0101 accounted for 20.17%, the homozygous HLA-E*0103/0103 accounted for 27.73%; heterozygous HLA-E*0101/0103 accounted for 52.10%; in homozygous HLA-E*0101/0101 group, 15 cases were infected with CMV and the CMV infection rate was 62.50%; in homozygous HLA-E*0103/0103 group, 16 cases were infected with CMV and the CMV infection rate was 48.48%; in heterozygous HLA-E*0101/0103 group 20 cases were infected with CMV and the CMV infection rate was 32.25%. As compared with the homozygous HLA-E*0101/0101 group, the CMV infection rate in HLA-E*0103 group displays statistical significance (P = 0.0295). The CMV infection rate occurred higher and its significance is statistical (P = 0.0074). It is concluded that the HLA-E gene polymorphism is associated with CMV infection after HLA-genoidentical bone marrow transplantation.

[Ex vivo inducing cultured Epstein-Barr virus specific cytotoxic T lymphocytes and evaluation of their killing effect].

This study was aimed to explore the method for induction and expansion of EB virus specific cytotoxic T lymphocytes (EBV-CTL) in vitro, and to detect their killing effect. Peripheral blood mononuclear cells (PBMNC) were collected from 6 EBV seropositive healthy donors, and EBV-transformed B lymphoblastoid cells (BLCL)were used as the antigen-presenting cells and antigen stimulant which was irradiated by 40 Gy (60)Co irradiator. The autologous PBMNC and irradiated BLCL were cultured to induce and expand the EBV-CTL, and the immunophenotype was identified by the flow cytometry. The killing effect of the EBV-CTL against the autologous BLCL (autoBLCL), the autologous PHA cultured B lymphoblastoid cells( PHA-BLCL), the allogeneic BLCL (alloBLCL) and the K562 cells were measured with LDH release assay under different effector-to-target ratio. The results showed that the 6 cell lines of EBV-CTL were induced and expanded from the EBV seropositive healthy donors, the overall increase in cell numbers varied from 18.6 to 55.0 times. After 10 stimulations, the specific killing efficiency of the EBV-CTL for the autoBLCL were 59.4%, 43.2% and 29.0% under the effector-to-target ratio of 20: 1, 10: 1 and 5: 1. The nonspecific killing efficiency for the PHA-blast, alloBLCL and K562 cells were 7.1%, 9.4% and 10.3% (P < 0.05) under the 20: 1 ratio; 6.6%, 8.3% and 8.1% (P < 0.05) under 10: 1; 5.4%, 7.3% and 6.3% (P < 0.05) under 5: 1, respectively. It is concluded that the EBV-CTL can be successfully induced and expanded ex vivo for specific killing of HLA matched BLCL and may become a potential treatment for EBV related post-transplant lymphoproliferative disorders.

[Quantitative monitoring of multi-donor chimerism after multi-donor allogeneic hematopoietic stem cell transplantation].

This study was aimed to establish a model for detecting the donor chimerism rate following the multi-donor hematopoietic stem cell transplantations, and simplify its calculation method. Patients with hematologic disease receiving allogeneic hematopoietic stem cell transplantation including single-donor and multi-donor were selected in this study and the donor cell chimerism rates were detected, using STR-PCR combined with capillary electrophoresis. The results indicated that the peaks of the sister alleles coming from the same individual were confirmed to have the approximate areas and can be replaced each other in the situation of mixed chimerism. In the calculation model, the value between reference chimerism and approximate chimerism have no significant difference using the hypothetical peak areas, and the result was confirmed to be accepted basing on typical measurement error between sister alleles (5% - 20%). It is concluded that the areas of share peaks can be replaced by non-share peaks and this conclusion can be used to calculate the double-donor CHM (DD-CHM)(%). Compared to the D alleles, R alleles show more strategic importance because it can lead to more accurate result and allowed simplifying the arithmetic calculations for DD-CHM(%).

[Culture and pluripotentiality of murine compact bone-derived mesenchymal stem cells].

This study was purposed to culture murine compact bone-derived mesenchymal stem cell (MSC) and analyze the immunological and trilineage differentiation potential. Tibia and femur were extracted. Bone marrow cells were flushed out and compact bone fragments were digested with collagenase. The digested cells were cultured in 6-well plates. The immunophenotype, immunosuppressive function and trilineage differentiation potential were analysed by flow cytometry, mixed lympocyte reaction and Oil red O, von Kossa and alcian blue straining, respectively. The results indicated that the pure compact bone MSC could be isolated with in 3 weeks. The resulting MSC had trilineage differentiation potential and immunosuppressive effect on mixed lymphocyte reaction. The count per minute (CPM) value in control group of BALB/c T cells cocultured with irradiated C57BL/6 T cells was (2.56 ± 0.31) × 10(4), while CPM values of mixed lymphocyte cocultured with C57BL/6 compact bone MSC at ratios of 100:1 and 10:1 were (0.47 ± 0.12) × 10(4) and (0.28 ± 0.09) × 10(4). The CPM value of control group was higher than those of MSC cocultured group (P < 0.001). Compact bone-MSC had an immunosuppressive effect on mixed lymphocyte reaction in a dose dependent manner. It is concluded that murine compact bone has rich MSC and the primary MSC is contaminated with less hematopoietic cells. Murine compact bone-MSC have immunosuppressive effect on mixed lymphocyte reaction and trilineage differentiation potential. Compact bone-MSC have promising experimental study value.

[Analysis of tyrosine kinases gene mutations in core binding factor related acute myeloid leukemia and its clinical significance].

OBJECTIVE: To assess the prevalence of several tyrosine kinases (TKs) gene mutations including c-Kit, FLT3 and JAK2 V617F in core binding factor related acute myeloid leukemia (CBF-AML), and analyze their impact on clinical characteristics and prognosis. METHODS: Mutations of c-Kit, FLT3-ITD and FLT3-TKD were detected by genomic DNA PCR and sequencing, and JAK2 V617F mutation screening by allele-specific PCR in 58 newly diagnosed CBF-AML patients [28 AML with inv(16) and 30 with t(8;21)], and analyze the patients clinical characteristics and prognoses. RESULTS: c-Kit aberrations were detected in 32.8% cases, including 6 cases mutated in exon 8 (mutKIT8) and 13 mutated in exon 17 (mutKIT17). MutKIT8 was more prominent in inv(16) than in t(8;21) patients (21.4% vs 0, P = 0.009). Only 2 cases had FLT3-ITD and 7 (12.1%) FLT3-TKD mutations. The result of JAK2 V617F mutation screenings in these CBF-AML patients was negative. The frequency of receptor tyrosine kinases(RTK) mutations was 46.6% and only one case had two kinds of missense mutations (mutKIT8 & TKD(+)). Median age of onset was higher for mutKIT17 than for wide-type c-Kit (wtKIT) patients (55 vs 31, P = 0.003). c-Kit mutations were significantly associated with decreased overall survival (OS) and continuous complete remission (CCR) rates (P = 0.053, and 0.048 respectively), and so did more for exon17 mutated patients reduced (P = 0.005, and 0.013 respectively). FLT3-TKD mutation showed no effects on prognosis of CBF-AML patients. CONCLUSIONS: RTK mutations are common in patients with CBF-AML. c-Kit mutations frequently and JAK2V617F mutation rarely appear in CBF-AML. c-Kit mutations, especially mutKIT17 confers higher relapse risk and poorer prognosis.