[Treadmill exercise test in patients with coronary artery myocardial bridging].

OBJECTIVE: To observe treadmill exercise test (TET) characteristics in patients with myocardial bridging (MB). METHODS: TET results from January 2003 to December 2010 were retrospectively analyzed in 156 patients with confirmed MB diagnosis. MB patients were divided into smoking group (68 cases) and non-smoking group (88 cases). Coronary angiography results were used to analyze the relations between MB length, myocardial ischemia and exercising duration. RESULTS: (1) MB was documented on two coronary arteries in 2 patients (1%), MB was detected in single artery in 154 patients (99%), of whom 146 cases were located at left anterior descending artery, 8 cases were located at right coronary artery. The degree of narrowing of MB was graded 1 (less than 50%) in 16 patients (10%), grade 2 (50% to 75%) in 108 patients (69%) and grade 3 (greater than 75%) in 32 patients (21%). The length of MB ranged between 4 to 40 mm, MB length was less than 10 mm in 40 patients (26%), between 11 to 20 mm in 48 patients (31%), between 21 to 30 mm in 44 patients (28%), greater than 31 mm in 24 patients (15%). (2) TET positive rate was 41% (64/156) and the TET positive rate was significantly higher in smoking group than in non-smoking group [57% (39/68) vs. 28% (25/88, P < 0.01)]. (3) The length of MB was positively related to the ST-segment depression (r = 0.723, P < 0.01) and negatively related to exercising duration (r = -0.828, P < 0.01). Heart rate was positively related to the ST-segment depression (r = 0.368, P < 0.01). CONCLUSIONS: TET may serve as a good test to assess myocardial ischemia in patients with MB. The length of MB is positively related with myocardial ischemia and negatively related with exercising duration. Smoking might increase myocardial ischemic incidence in MB patients, MB patients should be advised to stop smoking.

[Apoptosis of Kasumi-1 cells induced by puerariae radix flavones and its molecular mechanism].

OBJECTIVE: To explore the effects and the molecular mechanism of puerariae radix flavones (PRF) on acute myeloid leukemia cell line Kasumi-1 cells in vitro. METHODS: Kasumi-1 cells treated by PRF for 48 hours were observed with Wright's and Hoechst 33258 dying. The apoptotic cells were analyzed by flow cytometry with AnnexinV/PI staining. The expression levels of bcl-2, Bim and Caspase-3/-8/-9 protein were assayed by Western blot and the AML1-ETO fusion gene was detected by real-time polymerase chain reaction. RESULTS: PRF could induce Kasumi-1 cells to apoptosis effectively. The proportion of apoptotic cells in 50, 200 and 500 µg/ml PRF treatment groups were (14.1 ± 0.8)%, (17.7 ± 1.3)% and (32.4 ± 1.4)%, respectively, and significantly higher than that of control \[(7.8 ± 0.7)%\]. The relative expression levels of the anti-apoptotic Bcl-2 protein were 0.85 ± 0.05, 0.62 ± 0.07 and 0.43 ± 0.05; the apoptotic Bim protein were 0.21 ± 0.06, 0.39 ± 0.04 and 0.75 ± 0.05; the caspase-3 and caspase-9 were 0.92 ± 0.04, 1.21 ± 0.07, 1.33 ± 0.04 and 0.35 ± 0.05, 0.53 ± 0.03, 0.69 ± 0.07, respectively. Compared to the blank control group, all these changes were significant (P < 0.01). Nevertheless, nearly no changes could be observed on the expression level of AML1-ETO fusion gene and caspase-8 protein. CONCLUSION: Apoptosis of Kasumi-1 cells induced by PRF might correlate to the down-regulation of Bcl-2 protein expression and the activation of caspase-3 and caspase-8 protein in the cells. It seemed that all these effects had no relationship with the AML1-ETO fusion gene.

Combining nilotinib and imatinib improves the outcome of imatinib-resistant blast phase CML.

Imatinib resistance is an important hurdle in the treatment of chronic myeloid leukemia (CML), and CML patients with this drug resistance are often given a dismal prognosis. In this case report, an imatinib-refractory blast phase CML patient was treated with a combination of imatinib and nilotinib. A complete hematologic response was achieved within 3 months, the drug combination was well tolerated, and there was a relatively long bone-marrow complete remission. These results suggest that combining imatinib and nilotinib treatment may improve the outcome of imatinib-resistant CML patients in the blast phase. We hypothesize regarding the possible mechanism for the effectiveness of the drug combination by reviewing the recent literature.

A case report of a 33-year chronic phase survivor of chronic myeloid leukemia.

Here, we report a Philadelphia chromosome-positive chronic myeloid leukemia case with the longest chronic phase and overall survival to our knowledge ever reported in the medical literature. During the 33-year chronic phase, he was asymptomatic without any treatment and had normal blood cell values. BCR-ABL silencing might be referred to the uncommon long-term survivor.

[Clinical and biological features in refractory anemia with ringed sideroblasts with fluctuant platelet counts].

The objective of this study was to explore the differences between refractory anemia with ringed sideroblast (RARS) and RARS associated with marked thrombocytosis (RARS-T) in the clinical, biological features and prognosis. The morphological changes of cells were observed by bone marrow smear and biopsy. Immunologic phenotype was analyzed by flow cytometry, and chromosome was examined by conventional chromosomal analysis. JAK2 V617F and MPL W515L mutations were screened by allele-specific polymerase chain reaction (AS-PCR) and sequence analysis. The results showed that this case was clinically diagnosed as RARS with thrombophilia, the level of serum potassium was positively related with platelet counts. When platelets increased, the clusters of atypical giant platelets and megakaryocytes were observed in peripheral blood and bone marrow examined by bone marrow smear and bone marrow biopsy respectively, JAK2 V617F and MPL W515L mutations were negative. It is concluded that RARS may transform into RARS-T accompanied with megakaryocyte proliferation, large atypical platelets and negative JAK2 V617F. Preventing thrombophilia and monitoring relative gene mutations are necessary when atypical giant platelets and fluctuant platelet counts occurred in process of RARS with tendency to RARS-T.

[Inhibitory effect of flavonoids of puerarin on proliferation of different human acute myeloid leukemia cell lines in vitro].

This study was aimed to investigate the inhibitory effect of flavonoids of puerarin (PR) in different concentrations on proliferation of 4 kinds of acute myeloid leukemia (AML) cell lines (Kasumi-1, HL-60, NB4 and U937), and to explore its possible mechanism. The MTT method was used to detected the inhibitory effect of PR on proliferation of AML cell lines. The flow cytometry was adopted to determine the change of cell cycle in vitro. The results showed that a certain concentration of PR could inhibit the proliferation of these 4 cell lines effectively in time-and dose-dependent manners, and the intensity of inhibition on 4 kinds of AML cell lines was from high to low as follows: NB4>Kasumi-1>U937>HL-60. Meanwhile, PR could also change cycle process, cell proportion in G1/G0 phase decreased, cells in S phase increased and Sub-diploid peak also appeared. It is concluded that PR can selectively inhibit the proliferation of 4 AML cell lines and block cell cycle process, especially for NB4 cells.

[Apoptosis of NB4 cells induced by flavonoids of puerarin in vitro].

This study was aimed to investigate the effects of flavonoids of puerarin (PR) on apoptosis of acute promyelocytic leukemia (APL) cell line NB4 cells and its mechanism. The NB4 were treated with PR in vitro, the MTT assay was used to detect the inhibitory effect of PR on cell proliferation. The apoptosis of NB4 cells were detected by flow cytometry labelled with Annexin V/PI. The expressions of pml/rar alpha, bcl-2 and survivin were detected by real time reverse transcription-polymerase chain reaction (real time RT-PCR), the expressions of JNK, p38 MAPK, FasL, caspase 3, caspase 8 were detected by Western blot. The results showed that with the increasing of PR concentrations, the apoptosis rates of NB4 cells were gradually elevated. Simultaneously, the mRNA expression of pml/rar alpha, bcl-2 and survivin decreased, while the protein expression of JNK, FasL, caspase 3 and caspase 8 increased, which presented the positive correlation to PR concentrations. When PR combined with arsenic trioxide (ATO), the expression levels of above mentioned mRNA and protein decreased or increased more significantly. It is concluded that PR can effectively induce the apoptosis of NB4 cells. PR combined with ATO displays synergistic effect. It may be triggered by the activation of JNK signal pathway.