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T cells in grafts serve an important role in the pathogenesis of graft versus host disease (GVHD) and immune recovery during HLA matched allogeneic stem cell transplantation. However, the role of T cells in the haploidentical peripheral blood stem cell transplantation (Haplo-PBSCT) is yet to be determined. In the present study, the role of CD3+ T cells in grafts and impact on hematopoietic and immune recovery, cytomegalovirus (CMV) reactivation, GVHD, relapse, progress free survival and overall survival (OS) were evaluated and analyzed. A total of 30 patients who underwent haplo-PBSCT were included in the present study. CD3+ T cells accounted for a median of 23.1% (range 8-47.4%) with a median dose of 299.7x106/kg (range 104-623.4). Patients were divided into two groups according to the CD3+ T cell count: Above the median (high T cell group) and below the median CD3+ T cell (low T cell group). No significant difference was identified between neutrophil and platelet recovery time between two groups (P>0.05). The mean lymphocyte recovery time of high T cell group and low T cell group were 107.07 days (95% CI 79.88-134.25), and 50.4 days (95% CI 41.42-59.38), respectively. The lymphocyte recovery time of high T cell group was higher that of low T cell group (P 0.05). The cumulative incidence of grade II or above acute GVHD was higher in the high T groups compared with low T groups (P

Contents: Preface. Chinese Children: Introduction to Chinese children, Yunxiao Sun Introduction to Chinese children: a commentary, Yan Wang Chinese children's physical and mental development, Hongyan Sun Chinese children's physical and mental development: a commentary, Ginny Qin Zhan Chinese children's leisure, Weidong Chen Chinese children's leisure: a commentary, Vicky Chiu-wan Tam Chinese children's consumption, Xia Zhao Chinese children's consumption: a commentary, Bryan Tilt. Chinese Youth: Introduction to Chinese youth, Jieying Xi Introduction to Chinese youth: a commentary, Yan Xia Chinese youth's employment, Guoqi An Chinese youth in rural areas, Hua Zhang Chinese youth in rural areas: a commentary, I. Joyce Chang Chinese college students, Junyan Liu Chinese college students: a commentary, Baomei Zhao and Raymond E. Forgue. Chinese Children and Youth: Popular culture among Chinese youth, Changzheng Yang Popular culture among Chinese youth: a commentary, Shelley Hong Xu Only children in China, Yunxiao Sun and Xia Zhao Only children in China: a commentary, Li Huang Internet use among Chinese youth, Wei Bu Internet use among Chinese youth: a commentary, Xin-an Lu Juvenile delinquency in China, Ying Guan Juvenile delinquency in China: a commentary, Hong Lu Index.

In order to investigate the effect and mechanisms of interferon (IFN)-γ in combination with all-trans-retinoic acid (ATRA) on NB4 cells [ATRA-sensitive acute promyelocytic leukemia (APL) cell line] and NB4-R1 cells (ATRA-resistant APL cell line) and to search for a novel approach to solve the problem of ATRA resistance in APL, we initially treated NB4 and NB4-R1 cells with IFN-γ, ATRA and IFN-γ in combination with ATRA, respectively. The cell proliferation was then tested by MTT assay, and the cell differentiation was tested through light microscopy, by NBT test and flow cytometry (FCM). The expression of promyelocytic leukemia (PML) protein was observed by indirect immune fluorescent test. Results showed that ATRA inhibited the growth of NB4 cells, however, it could not inhibit the growth of NB4-R1 cells. IFN-γ inhibited the growth of both NB4 and NB4-R1 cells. Meanwhile, the growth inhibition effect of IFN-γ in combination with ATRA on both NB4 and NB4-R1 cells was significantly stronger than that of any single drug treatment. The results of the NBT reduction test and CD11b antigen detection by FCM indicated that IFN-γ induces the differentiation of NB4 and NB4-R1 cells to some extent. Moreover, the maturation degree of both NB4 and NB4-R1 cells induced by IFN-γ in combination with ATRA was more significant than that of IFN-γ or ATRA alone. After treatment with IFN-γ, the number of fluorescent particles in NB4 and NB4-R1 cell nuclei was higher than those in the control group, which indicated that IFN-γ may induce the expression of PML protein. Together, IFN-γ augments the proliferation inhibition effect of ATRA on NB4 and NB4-R1 cells through enhancing the expression of PML protein. IFN-γ in combination with ATRA not only strengthens the induction differentiation effect of ATRA on NB4 cells, but also can partially induce the maturation of NB4-R1 cells with ATRA resistance.

To explore optimum conditions for establishing a two‑dimensional gel electrophoresis (2-DE) map of the human acute promyelocytic leukemia (APL) cell line NB4 and to analyze its protein profiles, we extracted total proteins from NB4 cells using cell disruption, liquid nitrogen freeze-thawing and fracturing by ultrasound, and quantified the extracted protein samples using Bradford's method. 2-DE was applied to separate the proteins, which were silver-stained in the gel. Well‑separated protein spots were selected from the gel using the ImageMaster™ 2D Platinum analysis system. Moreover, the effects of various protein sample sizes (140, 160 and 180 µg) on the 2-DE maps of the NB4 cells were determined and compared. Matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDI-TOF-MS), peptide mass fingerprinting (PMF) and database searching were used to identify the proteins. When the quantity of loading proteins was 160 µg, clear, well-resolved, reproducible 2-DE proteomic profiles of the NB4 cells were obtained. The average number of protein spots in 3 gels was 1160±51 with an average matching rate of 81%. A total of 10 proteins were identified by mass spectrometry and database queries, certain proteins were products of oncogenes and others were involved in cell cycle regulation and signal transduction. In summary, 2-DE profiles of the proteome of NB4 cells were established and certain proteins were identified by MALDI-TOF-MS and PMF which lay the foundation of further proteomic research of NB4 cells. These data should be useful for establishing a human APL proteome database.

Although 90% patients with untreated acute promyelocytic leukemia(APL) obtain complete remission because of the usage of all-trans retinoic acid(ATRA), patients with ATRA-resistance are increased gradually. ATRA-resistance has become one of the main causes which affect the long-term therapeutic efficacy of APL. The mechanisms of ATRA-resistance are complex, which probably involve the metabolism of ATRA, abnormal expression of cellular retinoic acid binding protein(CRABP) and P-glycoprotein(P-gp), mutation of RARα and aberration translocation of APL. However, in these previous researches, it was one or a few proteins but not the entirety proteins that were emphasized on the mechanisms of ATRA-resistance. Comparative proteomics can analyze the entire protein expression in cells in whole and has the superiority in screening the drug-resistance proteins differentially expressed. In order to investigate the mechanisms of ATRA-resistance in APL in whole, we compared and analyzed the protein expression profiles between MR2 cells(APL cell line with ATRA-resistance) and NB4 cells(APL cell line with ATRA-sensitiveness) by comparative proteomics. After the total proteins of MR2 cells and NB4 cells were extracted respectively, they were separated by two-dimensional electrophoresis(2-DE). The differences in proteome profile between MR2 cells and NB4 cells analyzed by ImageMaster™ 2D Platinum software. The average protein spots in 2-DE maps of MR2 and NB4 cells were 1160±51 and 1068±33 respectively. 8 protein spots were selected to be identified by Matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDI-TOF-MS), in which the quantity of the protein differentially expressed was more than two times(≥2 or ≤0.5) between MR2 and NB4 cells’ 2-DE map. They were all successfully identified and their definite information was obtained. Among them, 6 proteins were probably involved in the mechanisms of ATRA-resistance in APL and they were Cofilin-1, Elongation factor 1-beta (EF-1β), Tropomyosin isoform(TM), High mobility group protein B1(HMGB1), Ran-specific GTPase-activating protein (RanGAP1) and Galectin-1. Moreover, so far there was no related report on the roles of HMGB1, RanGAP1 and Galectin-1 in the mechanisms of ATRA-resistance in APL. These differential proteins identified provide the new clues for us to further elucidate the mechanisms of ATRA-resistance from multiple factor.

More than 90% patients with untreated acute promyelocytic leukemia(APL) obtain complete remission clinically by using All-trans retinoic acid(ATRA), a strong differentiation inducer. However, the rapid development of ATRA-resistance brings a new problem to the treatment of APL. Interferon(IFN), as an important cytokine, has broad biological activities. It can not only inhibit the growth of tumor cells, but also reverse the drug-resistance of chemotherapy. As proved by some research, the mechanisms of ATRA-resistance are probably related to lacking some important proteins which synthesized by Interferon-γ (IFN-γ). In order to explore a new way to solve the problem of ATRA-resistance in APL, we investigate the effect and mechanisms of IFN-γ in combination with ATRA on the proliferation/differentiation of NB4 cells(APL cell line with ATRA-sensitiveness) and MR2 cells(APL cell line with ATRA-resistance) respectively. ATRA, IFN-γ and IFN-γ in combination with ATRA were incubated with NB4 and MR2 cells respectively. The cell proliferation was tested by MTT assay, the cell differentiation was tested through light microscope, by NBT reduction test and flow cytometry(FCM). The results showed that ATRA could inhibit the growth of NB4 cells significantly (P0.05). IFN-γ could inhibit the growth of both NB4 cells and MR2 cells slightly (P0.05). Although IFN-γ alone had no effect on the differentiation of either NB4 or MR2 cells (P>0.05), it could augment the differentiation of NB4 cells induced by ATRA (P

Although all-trans retinoic acid(ATRA) provides complete remission in 90% patients with untreated acute promyelocytic leukemia(APL), it becomes ineffective to quite a few APL patients who have received ATRA before when their disease relapsed and used ATRA again. Arsenic trioxide(ATO) can make APL patients with ATRA-resistance obtain complete remission again by inducing APL cells apoptosis. However, the molecular mechanisms of apoptosis in ATRA-resistance APL cells induced by ATO remain unclear. For this reason, we take the apoptotic MR2 cells (APL cell line with ATRA-resistance) induced by ATO as a model, to screen and identify the proteins related with ATO-induced apoptosis by comparative proteomics. After MR2 cells were dyed with annexin V and PI staining, the percentage of the apoptotic MR2 cells induced by 1.0μmol/L ATO for 0h, 6h, 12h, 24h and 48h respectively was detected by Flow cytometry. The results showed that the majority of the apoptotic cells were in the earlier and later stage of apoptosis respectively, when MR2 cells were treated with ATO for 24 and 48 hours in sequence. The total proteins of MR2 cells of the control group, the earlier stages apoptosis group and the later stages apoptosis group were separated by two-dimensional electrophoresis(2-DE) respectively. Then, the differences in proteome profile among three groups were analyzed by ImageMaster™ 2D Platinum software. 14 protein pots were selected to be identified by Matrix-assisted laser desorption/ionization time of flight-mass spectrometry(MALDI-TOF-MS), in which the quantity of the protein differentially expressed was more than two times(≥2 or ≤0.5) among MR2-0h, MR2-24h and MR2-48h cells’ 2-DE map. However, only 11 proteins were successfully identified and their definite information was obtained. Among them, there were 8 proteins that were all probably involved in the mechanisms of apoptosis in MR2 cells and they were Calreticulin(CRT), Heat shock 70 kDa protein(HSP70), High mobility group protein B1(HMGB1), Ran-specific GTPase-activating protein(RanGAP1), Elongation factor 1-beta(EF-1β), Beta-tubulin, Cofilin-1, and Prolyl 4-hydroxylase(P4H) respectively. CRT was probably related with the early stage of apoptosis in MR2 cells, while RanGAP1 and HSP70 might related with the late stage of apoptosis in MR2 cells. Moreover, so far there was no related report on the roles of CRT, HMGB1, RanGAP1, cofilin-1 and beta-tubulin in the mechanisms of APL cells apoptosis. These differential proteins identified provide the new clues for further researching the molecular mechanisms of apoptosis in the ATRA-resistance APL cells induced by ATO.