Online PBL teaching design and application based on curriculum integration / 中华医学教育探索杂志

Due to the impact of COVID-19, the online problem-based learning (PBL) teaching mode was first implemented based on the curriculum integration of basic medicine and clinical medicine in our university in 2020. A total of 357 eight-year program clinical medicine students from three grades participated in the online PBL courses. The students have had related skills and knowledge of integration curriculum, and the teachers have carried out sufficient analysis of learning situation, preparation of software and hardware, as well as teaching design. Teachers and students has communicated with each other smoothly and cooperated closely through the Tencent Conference software platform, therefore this teaching mode has gained better feedback among students, with higher satisfaction of courses and significantly improved students' learning enthusiasm. The curriculum integration has laid the foundation for the case design and application of online PBL teaching, while the success of online PBL teaching has also reflected the original intention of curriculum integration reform.

Magnetic-induced cell targeted transplantation promotes repair of large segmental femoral defects with tissue engineering bone loaded with fluorescent gene labeled cells / 中华创伤骨科杂志

Objective@#To investigate the effect of magnetic-induced cell targeted transplantation (MagIC-TT) on repair of bone defects in mice using therapeutic fluorescent gene labeled cells into bone tissue and its mechanism.@*Methods@#The proliferation, apoptosis and targeted migration ability were compared between magnetized and unmagnetized murine bone marrow stromal cells labeled with green fluorescent protein (GFP-BMSCs) (n=3). GFP-BMSCs were loaded into tissue engineering bone (TEB) by MagIC-TT in the experimental group (n=5) before the TEB was transplanted into the large femur defects in the model of red fluorescent protein (RFP) transgenic mice. In the control group (n=5) TEB was not loaded with GFP-BMSCs while in the blank group (n=3) the large femur defects were only fixated with intramedullary nails. The effects and mechanism of bone repair were explored 3 months after surgery using X-ray, micro-CT, semi-solid decalcification (SSD) and histology, respectively@*Results@#There were no significant differences between magnetized and non-magnetized GFP-BMSCs in proliferation (0.760±0.029 versus 0.733±0.033) or in survival rate (87.9%±1.0% versus 87.4%±2.0%) (P>0.05), but the mobility of magnetized GFP-BMSCs was significantly higher than that of non-magnetized GFP-BMSCs (P<0.05). The X-ray 3 months after surgery showed that the scaffolds in the experimental group were degraded and that the proximal and distal ends of the femoral defects were connected by new bone tissue. No new bone formation was found in the blank group while a small amount of bone formation was observed in the control group. The Micro-CT showed that stable new bone tissue formed in the femur defects after removal of intramedullary nails in the experimental group. The SSD showed that GFP-MSCs were densely distributed in the scaffolds with red fluorescent protein (RFP) recipient cells penetrating them, indicating involvement of both donor and recipient cells in the formation of new bone.@*Conclusions@#MagIC-TT can be used to promote introduction of therapeutic cells into bone tissue to achieve a fine effect on repairing bone defects. Dual fluorescence gene marking combined with SSD shows that both donor and recipient cells may take part in the bone repairing.

Magnetic-induced cell targeted transplantation promotes repair of large segmental femoral defects with tissue engineering bone loaded with fluorescent gene labeled cells / 中华创伤骨科杂志

Objective To investigate the effect of magnetic-induced cell targeted transplantation (MagIC-TT) on repair of bone defects in mice using therapeutic fluorescent gene labeled cells into bone tissue and its mechanism.Methods The proliferation,apoptosis and targeted migration ability were compared between magnetized and unmagnetized murine bone marrow stromal cells labeled with green fluorescent protein (GFP-BMSCs) (n =3).GFP-BMSCs were loaded into tissue engineering bone (TEB) by MagIC-TT in the experimental group (n =5) before the TEB was transplanted into the large femur defects in the model of red fluorescent protein (RFP) transgenic mice.In the control group (n =5) TEB was not loaded with GFP-BMSCs while in the blank group (n =3) the large femur defects were only fixated with intramedullary nails.The effects and mechanism of bone repair were explored 3 months after surgery using X-ray,micro-CT,semi-solid decalcification (SSD) and histology,respectively Results There were no significant differences between magnetized and non-magnetized GFP-BMSCs in proliferation (0.760 ±0.029 versus 0.733 ±0.033) or in survival rate (87.9％ ±1.0％ versus 87.4％ ±2.0％) (P＞ 0.05),but the mobility of magnetized GFP-BMSCs was significantly higher than that of non-magnetized GFP-BMSCs (P ＜ 0.05).The X-ray 3 months after surgery showed that the scaffolds in the experimental group were degraded and that the proximal and distal ends of the femoral defects were connected by new bone tissue.No new bone formation was found in the blank group while a small amount of bone formation was observed in the control group.The Micro-CT showed that stable new bone tissue formed in the femur defects after removal of intramedullary nails in the experimental group.The SSD showed that GFP-MSCs were densely distributed in the scaffolds with red fluorescent protein (RFP) recipient cells penetrating them,indicating involvement of both donor and recipient cells in the formation of new bone.Conclusions MagIC-TT can be used to promote introduction of therapeutic cells into bone tissue to achieve a fine effect on repairing bone defects.Dual fluorescence gene marking combined with SSD shows that both donor and recipient cells may take part in the bone repairing.

In vivo distribution of luciferase gene-labeled bone marrow mesenchymal stem cells infused through different approaches / 中国组织工程研究

BACKGROUND:Most bone marrow mesenchymal stem cel s are infused intravenously and have very low efficiency of homing to the bone marrow. However, cel infusion via the femoral approach is little reported. OBJECTIVE:To explore the distribution of luciferase gene modified red fluorescent protein transgenic bone marrow mesenchymal stem cel s in vivo through different infusion routes. METHODS:Luciferase gene modified bone marrow mesenchymal stem cel s at different gradients (5×106, 1×106, 1×105, 1×104) were seeded or injected into the in vitro pore plate or free femurs to observe the fluorescence imaging and select the best concentration of cel s. Luciferase gene modified bone marrow mesenchymal stem cel s at the best cel concentration were injected into the mice via the femur and the tail vein, respectively. The distribution of fluorescence and cel number in the mice were explored by using bioluminescence, pathological examination, flow cytometry and quantitative PCR. RESULTS AND CONCLUSION:Ex vivo fluorescence intensity of luciferase gene modified bone marrow mesenchymal stem cel s was positively correlated with the cel concentration;fluorescent cel s in vivo appeared in the femur first and then quickly spread to the lungs in the femur group, while fluorescent cel s in the tail vein group spread to the lungs quickly after cel infusion. Fluorescent cel s could be seen in the spleen, liver and other organs 24 hours later in the two groups. The distribution and migration of cel s in mice could be observed successful y by bioluminescence;5 minutes after cel infusion, the lungs of mice in the two groups began to emit fluorescence that could spread to the liver, spleen and other tissues 24 hours later, and the fluorescence intensity reached its peak after 15 minutes. The distribution of bone marrow mesenchymal stem cel s in mice had no significant difference between the femur group and the tail vein group. To conclude, cel injection through the bone marrow cavity and tail vein fails to promote the homing of bone marrow mesenchymal stem cel s to the bone marrow.

Sorafenib as salvage therapy in refractory relapsed acute myeloid leukemia with positive FLT3 mutation / 中华血液学杂志

<p><b>OBJECTIVE</b>To analyze the effect of sorafenib as salvage therapy used before and/or after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in refractory relapsed FLT3-positive acute myeloid leukemia (AML).</p><p><b>METHODS</b>A total of 16 patients with refractory relapsed FLT3-positive AML, including 10 refractory relapsed pre-transplantation and 6 relapsed after allo-HSCT, were enrolled in this retrospective study. Sorafenib treatment protocols included sorafenib in combination with chemotherapy inducing remission, and sorafenib monotherapy as mauntenance treatment after complete remission (CR).</p><p><b>RESULTS</b>Thirteen of the 16 patients achieved CR after one or two courses of induction therapy, including 7 refractory relapsed pre-transplantation and 6 relapsed after allo-HSCT. With a median follow up of 472 (range, 59-1569) days post-transplantation, 12 patients survived and 4 died. Causes of death included leukemia relapse (n=3) and acute graft-versus-host disease (n=1). The 2-year overall and disease-free survival post-transplantation of the 16 patients were (75.0±10.8) % and (50.5±13.7) % respectively. The main side effect of sorafenib was the skin rash. The incidence of rash was lower in the patients used sorafenib pre-transplantation than those post-transplantation (30.0% vs 75.0%, P=0.043).</p><p><b>CONCLUSION</b>Sorafenib used as salvage therapy befor and/or after transplantation for refractory relapsed FLT3-positive AML could reduce the relapse rate and improve the survival.</p>

Value of C-reactive protein level on transplantation day in predicting early post-transplant infections and outcomes of allogeneic hematopoietic stem cell transplantation / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the value of C-reactive protein (CRP) on transplantation day in predicting early post-transplant infections and outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT).</p><p><b>METHODS</b>We retrospectively analyzed the clinical data of 78 recipients undergoing allo-HSCT. The clinical reference value of CRP on transplantation day was determined, and its sensitivity and specificity for diagnosing bacteremia was analyzed using receiver-operating characteristic curve (ROC). The incidence of transplant-related complications, overall survival, and relapse rate of the patients were analyzed with respect to the CRP level.</p><p><b>RESULTS</b>The clinical reference value of CRP for diagnosing bacteremia was 23.3 mg/L (AUC=0.735 [95% CI: 0.623-0.848], P=0.001), which had a diagnostic sensitivity and specificity of 0.793 and 0.592, respectively. Compared with the patients with low CRP levels, the patients with high CRP levels tended to have delayed neutrophil reconstitution and platelet engraftment by 0.71 days (P=0.237) and 4.09 days (P=0.048), respectively, and had a significantly higher incidence of bacteremia (17.1% vs 53.5%, P=0.001) and CMV viremia (37.1% vs 72.1%, P=0.003) within 100 days following the transplantation; the incidences of EBV viremia, pulmonary invasive fungal infection, or acute graft versus host disease (aGVHD) showed no significant difference between the two groups (41.9% vs 22.9%, P=0.094; 14.0% vs 5.7%, P=0.285; 51.2% vs 45.7, P=0.656, respectively). During the follow-up for a median of 318 (7-773) days in high-CRP group and for 299 (78-747) days in low-CRP group, the high-CRP group showed a significantly lower 2-year overall survival than the low-CRP group (42.5% vs 78.4%, P=0.022), and tended to have a higher 2-year cumulative relapse rate (52.3% vs 19.8%, P=0.235). Logistic multivariate analysis identified a high CRP level on transplantation day as the independent risk factor for post-transplant bacteremia within 100 days (OR=5.090 [95% CI: 1.115 -23.229], P=0.036).</p><p><b>CONCLUSION</b>A high CRP level on transplantation day can be indicative of a high risk of early post-transplant bacteremia and CMV viremia and also a poor prognosis following allo-HSCT.</p>

Effect of intermediate-dose cytarabine on mobilization of peripheral blood hematopoietic stem cell in acute myeloid leukemia / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the impact of courses of intermediate-dose cytarabine (ID-Ara-C) chemotherapy on the efficiency of hematopoietic stem cell mobilization in acute myeloid leukemia (AML) patients with autologous hematopoietic stem cell transplantation (auto-HSCT).</p><p><b>METHODS</b>90 patients with de novo AML undergoing auto-HSCT between August 1999 and November 2012 were enrolled. All patients received the mobilization regimen of cytarabine and etoposide chemotherapy in combination with recombinant human granulocyte-colony stimulating factor (rhG-CSF). Stem cell apheresis was scheduled when blood leukocyte count recovered greater than 4.0 × 10⁹/L or the proportion of CD34⁺ cells greater than 1% in peripheral blood. The impact of ID-Ara-C courses on the mobilization efficiency was analyzed retrospectively.</p><p><b>RESULTS</b>According to the ID-Ara-C courses, patients were divided into group A (<2 courses), B (2 courses), and C (>2 courses). The median doses of CD34⁺ cells (×10⁶/kg) in three groups were 4.7, 2.7, 2.3, respectively (P=0.003). Of the available 87 patients who could be evaluated, 61 (70.1%) cases had CD34⁺ cells greater than 2.0 × 10⁶/kg, and 26 (29.9%) cases less than 2.0 × 10⁶/kg. Of the 26 patients without satisfactory mobilization efficiency, 7 (15.2%) were in group A, 10 (47.6%) in group B, and 9 (45.0%) in group C (χ²=10.05, P=0.007). In addition, patients with satisfactory mobilization efficiency (CD34⁺ cells ≥ 2.0×10⁶/kg) in groups C needed more times of collection, more volume of blood processed, and even high-dose and longer course of rhG-CSF (P<0.05). In univariate analysis. The ID-Ara-C courses and the cumulative dose were significant correlate with mobilization efficiency. In multivariate analysis, the ID-Ara-C courses was an independent correlation factor for mobilization efficiency (odd ratio=0.623, 95% confidence interval=0.418-0.926, P=0.019). The sex, age, cytogenetic risk, the standard chemotherapy courses did not correlate with mobilization efficiency.</p><p><b>CONCLUSION</b>The number of ID-Ara-C courses was independent factor for the mobilization efficiency and should be taken seriously in AML patients with auto-HSCT.</p>

Comparison of clinical efficacy between HLA-mismatched related and HLA-matched unrelated donor hematopoietic stem cell transplantation for hematopoietic malignancies / 中华血液学杂志

<p><b>OBJECTIVE</b>To compare the clinical efficacy of HLA- mismatched related donor (MRD) and HLA-matched unrelated donor (MUD) hematopoietic stem cell transplantation (HSCT) for hematopoietic malignancies.</p><p><b>METHODS</b>174 patients with hematopoietic malignancies undergoing allogeneic HSCT (allo-HSCT) (82 from MRD and 92 from MUD) between June 2002 and December 2012 were enrolled in this retrospective study. Hematopoietic engraftment, graft versus host disease (GVHD), relapse, overall survival (OS) and disease-free survival (DFS) were compared between MRD and MUD group.</p><p><b>RESULTS</b>There was no significant difference between MRD and MUD group in terms of age, gender, disease type and disease status before transplantation (all P>0.05). The incidence of Ⅰ-IV acute GVHD (aGVHD) was 62.2% and 54.3% in MRD and MUD group (P=0.295); the incidence of III-IV aGVHD between the two groups was 15.9% and 9.8% (P=0.229). The incidence of chronic GVHD (cGVHD) was 28.4% and 45.1% in MRD and MUD group (P=0.036), but there was no significant difference in the incidence of extensive cGVHD between the two groups (9.0% vs 12.2%, P=0.525). The mortality of GVHD was 8.5% and 10.9% in MRD and MUD group (P=0.605). The 10-year OS and DFS were (50.1±6.1)% and (48.8±6.1)% in MRD group, compared with (50.5±6.7)% and (46.3±6.2)% in MUD group (P=0.501, P=0.873, respectively). The 10-year cumulative relapse rate was (21.5±5.7)% and (37.6±7.3)% in MRD and MUD group (P=0.194).</p><p><b>CONCLUSION</b>MRD is equivalent to MUD in efficacy and safety. Without HLA- matched related donors, MRD is superior to MUD because donor source is unlimited and transplantation could be made promptly according to disease status.</p>

An Ultrasensitive Simultaneous Immunoassay Based on Arsenic and Mercury Ions Labeled SiO2@Au Nanoparticle Probes / 分析化学

An ultrasensitive immunoassay was developed based on As3+ and Hg2+ labeled SiO2 @ Au nanoparticles signal tags and hydride generation-atomic fluorescence spectrometry (HG-AFS) for the detection of carcinoembryonic antigen(CEA) and carbohydrate antigen 19-9 (CA 19-9) respectively. Firstly, amino SiO2@ Au NPs were synthesized for selective absorption of As3+ and Hg2+ ions respectively. Subsequently,the secondary antibody (Ab2) of CEA and CA 19-9 was respectively labeled on As3+ or Hg2+-SiO2 @ Au NPs to prepare the corresponding signal tags for CEA and CA 19-9. Based on the sandwich immunoassay scheme, the tags, two antigen and corresponding first antibodies were bio-conjugated on the bottom of 96-well plate at room temperature to form the immunocomplex. After it was dissolved in alkali solution, As3+ and Hg2+ ions were released in solution and detected by HG-AFS, which concentration was proportional with logarithms of CEA and CA 19-9. The reaction conditions were optimized and the tags were characterized. This assay was based on determination of the concentration of As3+ and Hg2+ for quantization of the corresponding CEA and CA 19-9 antigen. The assay showed a wide linear range from 0. 001 to 100. 0 μg / L for CEA and 0. 01-80 U/ mL for CA 19-9, and a lower detection limit of 0. 5 ng / L and 0. 005 U/ mL respectively. This proposed method was used in real serums samples, the results were consistence with that by ELISA. The immunoassay showed three orders of magnitude of sensitivity lower than that of ELISA, which provides a promising simultaneous immunoassay for the early diagnosis of cancer .

Conditioning regimen with or without total body irradiation for allogeneic hematopoietic stem cell transplantation in acute Ieukemia / 中华器官移植杂志

ObjectiveTo investigate the therapeutic effects of the conditioning regimen with or without total body irradiation on allogeneic hematopoietic stem cell transplantation in acute leukemia.Methods We retrospectively evaluated clinical outcomes in 287 allo-HSCT recipients with acute leukemia (ALL- 105,AML-129,and AUL-53) who received myeloablative conditioning regimen with or without total body irradiation from January 2002 to August 2011.Two hundred and six patients obtained complete remission (CR) and 81 non-remission (NR) before transplantation.One hundred and ninety-nine patients received conditioning with total body irradiation (TBI+ Cy group,9 Gy given over 2 days),and 88 patients received busulfan (BuCy group,3.2 mg·kg-1 ·d-1 ),both followed by cyclophosphamide.ResultsThere were no statistically significant differences in hematopoietic reconstitution,regimen-related toxicity (RRT),graft-versus-host disease (GVHD) and relapse between two groups.For patients with AML and AUL,there was no significant difference in the 5-year survival between the two regimens (P＞ 0.05),while for ALL-CR patients,the TBI + Cy regimen had a higher over survival rate (52.0％ vs.31.3％,LogRank=4.249,P＜0.05) and DFS (50.4％ vs.27.8％,LogRank =4.445,P＜0.05) than BuCy.In TBI + Cy group and BuCy group,the proportion of CD19+ B cells at the first month after HSCT was (4.04 ± 1.86)％ and (1.47 ±0.99) ％ (P＜0.05),that of NK cells at 12th month after HSCT was (23.38 ± 12.19) ％ and (13.11± 7.99) ％ (P＜0.05),and that of CD4+ CD45RO+ cells at 9th month after HSCT was (14.63 ±6.17)％ and (9.07 ± 3.12)％ (P＜0.01),respectively.ConclusionUsing TBI-containing regimen was more effective for treating ALL-CR patients than busulphan-containing regimen,but no difference was found for long-term outcomes in patients with AML and AUL between the two regimens.The 9 Gy TBI-based regimens may not affect recipients' thymic function,T-cells reconstitution and immune tolerance,coming out a non-increase of GVHD.

Allogeneic hematopoietic stem cell transplantation for blastic plasmacytoid dendritic cell neoplasms / 白血病·淋巴瘤

Objective To investigate the effect of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with intensified conditioning regimen followed by rapidly tapering immunosuppressants and sequential minimal residual disease (MRD)-guided donor lymphocyte infusion (DLI) post-transplantation on outcome of blastic plasmacytoid dendritic cell neoplasm (BPDCN).Methods Two cases of BPDCN from January 2009 to May 2011 in Nanfang hospital were diagnosed according to 2008 WHO classification of tumours of haematopoietic and lymphoid tissues.Case 1 initially presented with typical cutaneous involvement and was promptly diagnosed with CD+4CD+56LCA+TdT+CD+43 BPDCN by skin biopsy.Case 2 was recognized as acute lymphocyte leukemia and acute non-lymphocytic leukemia,which was diagnosed to BPDCN at recurrence through flow cytometry analysis.Total-body-irradiation plus cyclophosphamide based intensified conditioning regimen were followed by allo-HSCT from sibling donor.Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate.Anti-thymocyteglobulin was included additionally for haploid donor allo-HSCT.Multi-color labeling flow cytometry was performed to monitor MRD.Rapidly tapering of prophylactic immunosuppressants and sequential MRD-guided donor lymphocyte infusion (DLI) were performed to control relapse of primary malignancy.Results Two cases of BPDCN received allo-HSCT from sibling donor after intensified conditioning regimen.Both patients achieved complete remission and complete donor engraftment.Case 1 survived refractory acyclovir-resistant Epstein-Barr virus viremia benefiting from preemptive treatment with rituximab and DLI-induced grade Ⅳ acute GVHD,but died of thrombotic microangiopathy mixed with diffuse alveolar hemorrhage and sepsis on +243 days.Case 2 relapsed just 2 months after allo-HSCT despite DLI and rapidly tapering of CsA,died of sepsis followed by diffuse intravascular coagulation on +101 days.Conclusion BPDCN is characterized with typical cutaneous and/or bone marrow involvement with CD4+CD+56CD+123CD+43 blastic plasmacytoid dendritic cell and highly aggressive clinical course.Allo-HSCT seems to be a promising treatment for early phase of aggressive BPDCN aided with MRD monitoring and DLI,but it deserves more intensive researches to promote outcome of advanced staged BPDCN.

A comparison of toxicity and efficacy between busulfan plus fludarabine and busulfan plus cyclophosphamide for allogeneic hematopoietic stem cell transplantation in acute myeloid leukemia / 中华内科杂志

Objective To compare the transplant-related toxicity and the efficacy of busulfan/fludarabine (Bu/Flu) and busulfan/cyclophosphamide (Bu/Cy) as conditioning regimen in allogeneic hematopoietic stem cell transplantation (allo-HSCT) for acute myeloid leukemia(AML) in the first complete remission (CR1).Methods Totally 32 AML-CR1 patients underwent allo-HSCT were divided into Bu/Cy (Bu 3.2 mg· kg-1 · d-1,7-4 days before transplantation; Cy 60 mg · kg-1 · d-1,3-2 days before transplantation) and Bu/Flu (Bu 3.2 mg · kg-1 · d-1,5-2 days before transplantation; Flu 30 mg · m-2·d-1,6-2 days before transplantation) groups.The regimen-related toxicity (RRT),incidence and severity of graft-versus-host disease (GVHD),3-year cumulative relapse rate,non-relapse mortality (NRM),3-year event-free survival (EFS) rate and overall survival (OS) rate were compared between the two groups.Results The median follow-up duration was 617.5 (6-1261) days.All patients achieved successful engraftment on 30 day after transplantation.There were no significant differences in the median time to neutrophil engraftment (P =0.121) and platelet engraftment (P =0.171) between the two groups.The median duration of neutrophil count under 0.1 × 109/L and platelet count under 20 × 109/L in the Bu/Cy group were significantly longer than those in the Bu/Flu group (P =0.000 and P =0.047).The incidence of grades Ⅱ-Ⅳ RRT were 68.8％ and 25.0％ (P =0.032) in the Bu/Cy and the Bu/Flu groups,respectively.There were no significant differences in the incidence of acute GVHD (P =0.149),chronic GVHD (P =0.149),incidence of NRM (P =0.333),3-year cumulative relapse rates (P =0.834),3-year EFS rate (P =0.362) and OS rate (P =0.111) between the two groups.Conclusion Compared with Bu/Cy,Bu/Flu is a myeloablative condition regimen with milder bone marrow suppression and lower RRT incidence rate in allogeneic HSCT for AML-CR1 patients without compromising the efficacy.

HIGH EFFICIENCY OF RETROVIRUS MEDIATED GENE TRANSFER ACHIEVED BY FLOW-THROUGH TRANSDUCTION SYSTEM / 解放军医学杂志

Retrovirus (RV) is the most widely used vector for gene transfer, but its efficiency is very low for human cells. A Flow-through Transduction System made in General Hospital of PLA was used to deliver interleukin-12 RV vector into human leukemia cell line K562. Compared with static procedure, the efficiency could be significantly improved,and detected by clony forming units (CFU) for NeoR gene in semisolid culture medium with G418 (83.1%±3.9% vs 9.2%±2.3%, P＜0.01). No significant difference was found in the levels of IL-12 p70 protein expression detected by ELISA, by flow-through transducted cells without G418 selection and by statically-transducted cells with G418 selection (11.3±7.5ng/ml vs 12.0±6.4ng/ml, P>0.05), while statically transducted cells without G418 selection could express very low IL-12 (0.1±0.024ng/ml，P＜0.01)。The Flow-through Transduction System is efficient and easy for use, it can be widely used in research and clinic of gene therapy.

THERAPEUTIC EFFECTS OF INTERLEUKIN-12 GENE in vivo VACCINE FOR MURINE T CELL LYMPHOMA (EL4) IN C57BL/6 MICE / 解放军医学杂志

C57BL/6 synergistical mice were divided into 4 groups (10 mice each). The first group was negative control without any interference. Each mouse in the other 3 groups was subcutaneously inoculated with 1 10 6 wide type (wt) EL4 tumor cells. Then each group was treated either with interleukin 12 (mIL 12) in vivo vaccine or NeoR control vaccine or PBS(positive control group) on day 1, 7, 14, 21, on the same place where wt EL4 tumor was inoculated. mIL 12 in vivo vaccine and NeoR control vaccine were package cells which can produce retrovirus (RV) with mIL 12 or NeoR gene, the vaccine was 60 Co irradiated and injected (1?10 7 cells/mouse). All mice in positive group and NeoR control group died of tumors in a month, while 5/10 mice in mIL 12 in vivo vaccine groups survived without tumors for more than 60 days. The 5 survived mice were rechallenged with 5?10 5 wt EL4 cells, 3/5 mice even survived without tumors for another 60 days. Among the mice with tumors in vivo vaccine group mice, compared with the controls, the development of tumors was delayed ( P

Assessment of bcr/abl expression by real-time quantitative PCR in chronic myeloid leukemia patients after imatinib mesylate treatment / 解放军医学杂志

Objective To set up a new real-time quantitative PCR method for the detection of minimal residual disease in chronic myeloid leukemia patients, and to assess the bcr/abl fusion gene expression in chronic myeloid leukemia patients before and after treatment with imatinib mesylate by real-time quantitative PCR method. Methods The bcr/abl fusion gene expression in 30 patients with bcr/abl-positive chronic myeloid leukemia was analyzed by using real-time quantitative reverse transcription PCR (RQ-PCR) method. The patients treated with imatinib in a dose of 400mg/d for 1 year and 2 years were also examined (8 cases for each). In 19 new patients the same study was also conducted. Results The real time quantitative PCR method could detect 10 copies in the test. The average bcr/abl expression levels in new patients or patients who had been treated with imatinib for 1 year and 2 years were 68.18%?26.67%, 0.16%?0.15% and 0.04%?0.02%, respectively. The average logarithm reduction values after treatment were 2.82 in the first year and 3.36 in the second year. In 25% of patients (4/16) negative FISH results could not be obtained, but it was much lower than that of before imatinib-treatment. When FISH became negative, RQ-PCR showed positive results. Conclusions RQ-PCR is a more sensitive technique in the detection of bcr/abl fusion gene than the FISH. It is an important way to monitor the tumor cell during the treatment with imatinib mesylate in chronic myeloid leukemia patients.

HIGH EFFICIENCY OF RETROVIRUS MEDIATED GENE TRANSFER ACHIEVED BY FLOW-THROUGH TRANSDUCTION SYSTEM / 解放军医学杂志

Retrovirus (RV) is the most widely used vector for gene transfer, but its efficiency is very low for human cells. A Flow-through Transduction System made in General Hospital of PLA was used to deliver interleukin-12 RV vector into human leukemia cell line K562. Compared with static procedure, the efficiency could be significantly improved,and detected by clony forming units (CFU) for NeoR gene in semisolid culture medium with G418 ( 83.1%?3.9% vs 9.2%?2.3%, P0.05), while statically transducted cells without G418 selection could express very low IL-12 (0.1?0.024ng/ml,P