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Low-cost catalysts with high activity are in immediate demand for energy storage and conversion devices. In this study, polyvinyl pyrrolidone was used as a complexing agent to synthesize La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) perovskite oxide. The obtained porous layered LSCF has a large specific surface area of 23.74 m2/g, four times higher than that prepared by the traditional sol-gel method (5.08 m2/g). The oxygen reduction reaction activity of the oxide in 0.1 mol/L KOH solution was studied using a rotating ring-disk electrode. In the tests, the initial potential of 0.88 V (vs. reversible hydrogen electrode) and the limiting diffusion current density of 5.02 mA/cm2 were obtained at 1600 r/min. Therefore, higher catalytic activity and stability were demonstrated, compared with the preparation of LSCF perovskite oxide by the traditional method.

Rationale Concurrent case of nasopharyngeal carcinoma (NPC) and acute myeloid leukemia (AML) has not been reported. Here, we report a case of NPC, who was concurrently suffered from AML one mother after the NPC diagnosis. Patient concerns The patient was a 45-year-old male who presented with a mass on his right side neck. Diagnoses The patient was diagnosed with Epstein-Barr virus negative type-2 non-keratinizing carcinoma with clivus involvement and unilateral metastasis to the cervical lymph node. Interventions He was treated with one cycle of cisplatin and 69.76 Gy of concurrent external-beam radiation. Outcomes Three months after completion of chemo-radiotherapy, the patient was diagnosed as acute myeloid leukemia, which achieved complete remission after one course induction chemotherapy. Two months later, however, the patient was diagnosed as central nervous system leukemia. He ultimately died of relapsed leukemia. The overall survival of the patient was 10 months. Lessons The co-occurrence of NPC and AML is rare and prognosis is poor. Radiotherapy in NPC can disrupt the blood-brain barrier, which may contribute to the pathogenesis of central nervous system leukemia. Early alert and prevention of central nervous system leukemia following radiotherapy in NPC patient is recommended.

To evaluate the efficacy of imatinib mesylate (IM) for patients with newly diagnosed chronic myeloid leukemia (CML) and patients after failure of Recombinant Human interferon-α2b (IFN-α2b) therapy.A total of 86 patients with CML in chronic-phase, including 61 newly diagnosed cases and 25 cases of IFN-α2b failure, who received IM at 400 mg daily were retrospectively analyzed. Conventional cytogenetic analysis of R-banding was used to detect chromosome abnormalities and real-time PCR was used to detect BCR-ABL fusion gene.81.9% of newly diagnosed patients and 36.0% of IFN-α2b failure patients achieved partial cytogenetic response (PCyR) by 6 months. In addition, 86.9% of newly diagnosed patients and 68.0% of IFN-α2b failure patients achieved complete cytogenetic response (CCyR) in 24 months. There was significant difference between two groups (P0.001). The median time achieved CCyR in newly diagnosed group and IFN-α2b failure group were 6 months and 15 months, respectively. Compared with newly diagnosed group, IFN-α2b failure group showed lower rate of complete molecular remission (CMR) (70.4% vs 40.0%, P=0.033). There are 14 patients (22.9%) in newly diagnosed patients with cytogenetic resistance, among whom 4 with primary cytogenetic resistance; while there were 14 patients (56.0%) in IFN-α2b failure group with cytogenetic resistance, all of whom with primary resistance.Compared with newly diagnosed patients, CML patients after failure of IFN-α2b therapy have a high rate of primary cytogenetic resistance and low response rate to IM.

To explore the efficacy and safety of HAA regimen (homoharringtonine, cytarabine and aclarubicin) in the treatment of 150 newly diagnosed adult acute myeloid leukemia (AML).All patients entered the study from May 1999 to June 2008 were treated with HAA regimen. Cox-survival analysis was used to estimate the survival rate and differences between M(1)/M(2) and M(4)/M(5) were compared with 2-sided log-rank test.Out of the 150 patients, 121 (81%) achieved complete remission (CR). After the first course, CR rate was 68%. The CR rates of 97%, 84% and 38% were achieved in patients with favorable, intermediate and unfavorable cytogenetics, respectively. For the patients with CR, the median follow-up time was 16.5 (1.5 - 100.5) months, and the estimated 3-year survival rate was 45%. The estimated 3-year relapse free survival rate was 52% for the 121 patients with CR.HAA regimen may be an efficacious and safe regimen with a good toleration in the induction therapy for newly diagnosed AML, and a high CR rate could be achieved with only one or two courses.

To detect the expression levels of telomere binding factor 2 (TRF2) on leukemia cell lines and primary leukemia cells.The expression of TRF2 mRNA was detected with quantitative real-time RT-PCR in leukemia cell lines and primary leukemia cells. The Western blot analysis was used for the detection of TRF2 protein expression.TRF2 was overexpressed in T-cell leukemia cell lines but not in myelogenous leukemia cell lines. Significant higher expression levels of TRF2 were observed in primary leukemia cells from patients with M0 and M1 subtypes of acute myelogenous leukemia (AML) compared with normal control and other subtypes of AML.Increased TRF2 expression levels are found in T-cell leukemia cell lines and AML patients with poor prognosis, which suggests that TRF2 expression might be related to the prognosis of leukemia.

To investigate the anti-tumor effect and the possible mechanism of arsenic trioxide (ATO) alone or in combination with thalidomide (THAL) for treatment of SCID mice model transplanted with human myelodysplastic syndrome (MDS) cell line MUTZ-1 cells.(1) The animal model was established in SCID mice; 75 SCID mice and 10 BALB/CA-nude mice were studied in this experiment. MUTZ-1 cells were cultured in vitro and made for mono-cell suspension (with 1 x 10(8)/ml cell density and in exponential growth behavior) and were subcutaneously implanted into 4-6-week-old first-generation SCID mice and BALB/CA-nude mice. The biological characteristics of the subcutaneous tumor cells were evaluated by the methods of cell morphology, histopathology, immunology by flow cytometer, chromosome analysis and immunohistochemistry (IHC). Subsequently, the tumor cells from first-generation mice model were respectively subcutaneously implanted into 61 second-generation SCID mice and 8 BALB/CA-nude mice and the rate of the tumor formation and the latent period of the tumor formation were observed. (2) In vivo, 56 MDS-SCID mice were randomly grouped; 40 of them were used as ATO treated groups [5.0 microg or 7.5 microg/(g.d) intraperitoneal injection (i p) 5 d a week, x 3 weeks] alone or in combination with THAL 8 microg/(g.d), x 3 week or THAL alone and 16 mice as the control groups [with 0.9% NaCl 10 microl/(g.d) i p or untreated]. The mean tumor diameters (MTD) of subcutaneous tumors were measured with slide gauge and the therapeutic effects and the survival period and the rates of survival were evaluated by the methods of histopathology, IHC, microvessel density count (MVD), DNA ladder, TUNEL and PI with flow cytometry.(1) The rate of the subcutaneous tumor formation was higher (98.4%, 60/61) in SCID mice than in BALB/CA-nude mice (62.5%, 5/8) (P = 0.0027). The latent period of the tumor formation was significantly longer (23 - 28 d, median 26 d) in BALB/CA-nude mice than that in SCID mice (10 - 17 d, median 12 d) (Z = 4.605, P0.001). The biological characteristics of the tumor cells in the MDS-SCID mice model were evaluated and considered as of anthropo-source and were consistent with that of MUTZ-1 cells, which showed that the MDS-SCID mice model was successfully established. (2) In vivo, the marked inhibitory effect on the subcutaneous tumors growth (F = 146.94, P = 0.000) and the higher rates of cells apoptosis were seen in the groups treated with ATO 5.0 microg or 7.5 microg alone or in combination with THAL than in control groups (F = 30.10, P = 0.000). The longer-survival periods (F = 25.11, P0.01) with lower toxicity were only observed in lower-dose group of ATO 5.0 microg than in other treated groups and control groups. THAL alone group had a mild inhibitory effect on the tumors growth (2 weeks) with a longer-survival period and higher-rate of survival than controls, but had no events of cell apoptosis. The expression of vascular endothelial growth factor (VEGF) protein and CD34 protein and MVD were markedly down-regulated by THAL compared with control groups (P0.01), suggesting that the possible mechanisms of the inhibitory effect on tumor growth by THAL related to inhibition of vascular endothelial growth. The legs paralysis in 2 MDS-SCID mice was observed after treatment with THAL alone (11 d and 15 d, respectively), which were considered as the side-effect of THAL associated with deep venous thrombotic (DVT) events and the mechanism for these events is unclear. The therapeutic effects were unsatisfied in the group treated with ATO 7.5 microg in combination with THAL due to more intense toxicity and the shorter-survival periods than other treated groups (P0.001).(1) The Hum-MDS-SCID mice model was successfully established, which served as an animal model for studying pathogenesis of MDS and therapeutic agents selection. (2) ATO had marked inhibitory effect on the subcutaneous tumors growth in MDS-SCID mice model in vivo. The longer-survival periods and higher-rates of survival with lower toxicity were observed in lower-dose ATO (5.0 microg) alone than other groups. The mechanisms of the anti-tumor effect of ATO were considered to be related to inducing cells apoptosis, but in the case of THAL, related to inhibition of vascular endothelial growth. (3) The results do not support the preconceived hypothesis of a synergistic effect of ATO (7.5 microg) in combination with THAL for treatment of MDS mice model due to the more intense toxicity and the shorter-survival periods in the treated group. Whether or not this will translate into clinically relevant effect of the ATO or THAL in MDS patients deserves further investigation.

To explore the implication of karyotype analysis in diagnosis and prognosis of myelodysplastic syndrome (MDS).The chromosomes were prepared with direct method, brief culture of cells and R-banding techniques, and then the karyotypic analysis was performed.Seventy-seven out of 283 patients (27.21%) had karyotypic abnormalities, including the numeral abnormalities of chromosomes and structural alterations. The most common chromosomal aberrations were +8, -20/20q-, -Y, translocation, -7/7q-, +9, -5/5q-. The rate of abnormal karyotype in refractory anemia with erythroblasts (RAEB) and refractory anemia erythroblasts-transformation (RAEB-t) was much higher than in refractory anemia (RA). Patients with abnormal karyotype or higher IPSS scores had a higher risk of transformation into acute leukemia than patients with normal karyotype or lower IPSS scores (P0.05).MDS is a highly heterogenous disorder and karyotype analysis is helpful for its diagnosis and prognosis estimation.

To investigate the expression of WT1 gene in myelodysplastic syndrome (MDS) and to explore its clinical implications.Expression of WT1 mRNA was detected in 53 patients with myelodysplastic syndrome and 10 healthy subjects by reverse transcriptase polymerase chain reaction (RT-PCR).WT1 gene was expressed in all MDS patients. The positive rate and expression level in MDS patients were higher than those in healthy subjects. The positive rates of WT1 expression in MDS-RAEB and MDS-RAEB-t groups were higher than those in MDS-RA and MDS-RAS groups. The expression level was gradually increased from MDS-RA and MDS-RAS groups to MDS-RAEB and MDS-RAEB-t groups.The expression of WT1 gene might be associated with the development of MDS, and it can be used for risk assessment and monitor of disease progression and therapeutic effects in MDS patients.

To investigate the mechanisms of the telomerase regulations during the apoptosis of the human MDS-RAEB cell line MUTZ-1 cells induced by arsenic trioxide (As(2)O(3)), telomerase activity was detected by TRAP-ELISA and the expressions of mRNAs of hTERT, TRF1 (TTAGGG repeat binding factor 1), TRF2 (TTAGGG repeat binding factor 2), bcl-2, and bax genes were detected by RT-PCR. Apoptosis was detected by translocation of phosphatidylserine (PS) by flow cytometry. The results showed that 1 - 8 micromol/L of As(2)O(3) induced typical apoptosis of MUIZ-1 cells in the dose-and time-dependent manners, the telomerase activity could be down-regulated at this concentration and negatively correlated with increased apoptosis (r = -0.938, P = 0.018). The expression of telomerase activity was positively related to the expression of hTERT (r = 0.783, P = 0.022), but As(2)O(3) had no effect on the mRNA expression of TRF1 and TRF2 genes. The inhibition of telomerase activity by As(2)O(3) on MUTZ-1 cells was accompanied with the low expression of bcl-2 gene and the decrease of bcl-2/bax ratio. It is concluded that the apoptosis of MUTZ-1cells induced by As(2)O(3) may occur via the inhibition of telomerase activity and down-regulation of the expression of hTERT mRNA, and this may be one of the mechanisms inducing apoptosis in MUTZ-1 cells treated by As(2)O(3).

To explore the incidence and prognostic significance of chromosome 7 anomaly in acute leukemia.Conventional cytogenetic analysis of R-band was used to detect the abnormalities of chromosome 7 in 410 acute leukemia patients.Thirty-two cases (7.8%) with abnormalities of chromosome 7, of which 19 (59.4%) had -7/7q-; 3(9.4%) had t(7;11); and the rest had other abnormalities such as der(7), +7, t(2;7), t(5;7), t(7;9), t(7;8) and dic(1;7). The incidence of -7/7q- in M0, M1 and M2 was higher than that in other subtypes of acute myeloid leukemia (AML). Twenty cases had additional cytogenetic aberrations, such as t(9;22) with -7, +8, -5. In 30 cases treated with chemotherapy, 11 cases acquired complete remission (CR) and the CR rate was lower than that for all concurrent cases of acute leukemia(36.7% vs 65.8%); the CR rate of AML with -7/7q- was lower than that of AML with normal karyotype(25% vs 55.6%). There was no difference in the CR rate between acute lymphocytic leukemia(ALL) with -7/7q- and ALL with normal chromosome (57.1% vs 77.8%), but 4 cases with -7/7q- which attained complete remission for a time relapsed early. In other 11 patients with additional chromosome 7 aberration, only 4 patients acquired CR.-7/7q- was the frequent aberration in chromosome 7 anomaly, which was often detected in M0, M1 and M2. It might be associated with the pathogenesis of acute leukemia; the patients with chromosome 7 anomaly had poorer prognosis.

To study the expression and significance of WT1 gene in patients with myelodysplastic syndrome (MDS) and acute leukemia (AL), RT-PCR was applied to monitor WT1 gene expression in 22 patients with MDS and in 69 patients with AL. The results showed that the positive rate of WT1 mRNA in MDS-RA and MDS-RAS was lower than that in MDS-RAEB and MDS-RAEB-t (10% versus 91.7%, P0.01). WT1 mRNA could be expressed in all subtype of AL, It was detected in 69% of newly diagnosed and relapsed patients, and in 12.5% patients CR. There was no difference at the relative expression level between newly diagnosed AL patients and relapsed patients, while the relative level of WT1 in MDS-RAEB and MDS-RAEB-t was lower than that in newly diagnosed AL. The CR rate in AML patients with positive expression was lower than that in patients with negative expression (41% versus 78%, P/= 0.05). AML patients with relative level of WT1 mRNA/= 1 had lower CR rate (18%) than those with relative level1 (55%). It is concluded that the expression of WT1 gene in patients with MDS-RAEB and RAEB-t was higher than that in patients with RA and RAS. The detection of WT1 gene may be useful for assessing disease progress of patients with MDS. The expression of WT1 gene and its expression level have associated with the prognosis of newly diagnosed patients with AL, that WT1 gene may be an independent prognostic factor in AML.

To study the role of trisomy 8 in pathogenesis and progression of hematologic disease with trisomy 8.The clinical data on 38 cases with trisomy 8 were investigated retrospectively. Fluorescence in situ hybridization (FISH) using Spectrum Orange labeled chromosome 8 centromere specific probe was carried out to detect trisomy 8 in 10 cases.Thirty-two of 38(84.2%) cases with trisomy 8, and fourteen of 17(82.4%) cases with trisomy 8 as the sole chromosome aberration were myeloid disorders such as myelodysplastic syndrome (MDS), acute myelocytic leukemia (AML), chronic myelocytic leukemia (CML). The incidence of trisomy 8 was higher in myeloid disease than in lymphocytic disease (5% vs 1.3%); the incidence of trisomy 8 was higher in acute monocytic leukemia than in other AML (6.1% vs 2.4%), and the incidence of trisomy 8 in chronic myelomonocytic leukemia( CMML) was higher than that in other myelodysplastic syndrome (MDS) (25% vs 13.2%); 17 cases had trisomy 8 as the sole chromosome aberration, 21 cases had other additional chromosome aberrations. The chromosome aberration was confirmed by FISH in 10 cases with trisomy 8 as the sole chromosome aberration. Eleven cases were treated with chemotherapy, among them only 10 cases data were available. Seven cases acquired complete remission but 3 of them were M3, the other 3 cases had no response after two courses of chemotherapy.Trisomy 8 may play an important role in the pathogenesis and progression of the hematological disease, especially myeloid disease. Trisomy 8 might be related with differentiation abnormality of monocyte.