[The Role and Mechanism of MiR-451 in Multidrug Resistance of Leukemia Cell Line K562/A02].

Objective: To detect the differential expressions of miR-451, and in drug-sensitive leukemia cell line K562 and drug-resistant cell line K562/A02, and explore the regulatory relationship between miR-451 and the expressions of and , and the mechanism of miR-451 involved in drug resistance in leukemia.

Methods: CCK-8 assay was used to detect the drug resistance of K562/A02 and K562 cells. Quantitative Real-time PCR (qRT-PCR) was used to verify the differential expressions of miR-451 in K562 and K562/A02 cells.

The regeneration of Acer rubrum L. "October Glory" through embryonic callus.

Background: Tissue culture and rapid propagation technology is an important way to solve the difficulties of plant propagation. This experiment aims to explore the appropriate conditions at each stage of the red maple's tissue culture process and to obtain plantlets, thus providing a theoretical basis for the establishment of the red maple's tissue culture system.

Results: The results showed that the stem segment is the most suitable explant for inducing embryogenic callus.

A TET2 rs3733609 C/T genotype is associated with predisposition to the myeloproliferative neoplasms harboring JAK2(V617F) and confers a proliferative potential on erythroid lineages.

Common germline single-nucleotide polymorphisms (SNPs) at JAK2 locus have been associated with Myeloproliferative neoplasms (MPN). And, the germline sequence variant rs2736100 C in TERT is related to risk of MPN, suggesting a complex association between SNPs and the pathogenesis of MPN. Our previous study (unpublished data) showed that there was a high frequency distribution in rs3733609 C/T genotype at Ten-Eleven Translocation 2 (TET2) locus in one Chinese familial primary myelofibrosis.

Analysis of clinical and laboratory characteristics in 42 patients with thrombotic thrombocytopenic purpura from a single center in China.

Thrombotic thrombocytopenic purpura (TTP) is a life-threatening disease characterized by microvascular platelet deposition and thrombus formation with resulting microangiopathic hemolytic anemia. Deficiency of the von Willebrand factor cleavage protease, also known as ADAMTS 13, has been implicated as an important etiological factor in TTP. Little studies were obtained on Chinese patients with TTP until now.

[Screen of phosphopeptide specific for acute leukemia].

Objective: To screen phosphopeptide specific for acute leukemia.

Methods: Mononuclear cells from bone marrow were collected from 16 newly diagnosed acute lymphoblastic leukemia (ALL) and 20 acute myeloid leukemia (AML) patients. Peptides were extracted and purified, analyzed by immunoprecipitation and liquid chromatography coupled with tandem mass spectrometry (LC-MS).

[Screening for drug resistance related microRNAs in K562 and K562/A02 cell lines].

Objective: To explore the relationship between microRNA and drug resistance in leukemia treatment by screening and identifying the microRNAs which differentially express in K562 cell line and its adriamycin resistant cells-K562/A02 cell line.

Methods: The drug resistance potency of K562/A02 cells was evaluated by MTT assay. P-gp expression of K562 and K562/A02 cells were detected by flow cytometry (FCM).

Use of all-trans retinoic acid in combination with arsenic trioxide for remission induction in patients with newly diagnosed acute promyelocytic leukemia and for consolidation/maintenance in CR patients.

In the present study, 90 patients with newly diagnosed acute promyelocytic leukemia (APL) were studied for all-trans retinoic acid (ATRA) and arsenic trioxide (As(2)O(3)) combination treatment in remission induction and postremission therapy. In addition, 20 APL patients who had achieved complete remission (CR) with an ATRA-based regimen received ATRA/As(2)O(3) combination for consolidation and maintenance were also enrolled. The results showed that ATRA/As(2)O(3) combination therapy yielded a high CR rate of 93.

Fms-like tyrosine kinase (FLT) 3 and FLT3 internal tandem duplication in different types of adult leukemia: analysis of 147 patients.

Aim: To assess the expression level of fms-like tyrosine kinase 3 (FLT3), the incidence of FLT3/internal tandem duplications (ITD) mutation, and prognostic value of FLT3 changes in different types of adult leukemia.

Methods: Bone marrow mononuclear cells were isolated from 147 adult patients with leukemia. Reverse transcriptase polymerase chain reaction (PCR) was used to screen FLT3/ITD mutation and quantitative PCR was performed to evaluate the expression of the FLT3 transcript.

Arsenic trioxide, thalidomide and retinoid acid combination therapy in higher risk myelodysplastic syndrome patients.

Objective: To evaluate the clinical efficacy and safety of arsenic trioxide, retinoic acid and thalidomide combination therapy in higher risk MDS.

Methods: Twenty-one patients diagnosed with higher risk MDS were administered 10mg/day arsenic trioxide intravenously for 10 days, 40mg/day retinoic acid orally for 2 weeks and 100mg/day thalidomide orally for 4 weeks per cycle.

Results: After at least two treatment cycles, 10 patients showed hematologic responses.

[Acute monocytic leukemia after orthotopic liver transplantation: clinical features, molecular genetics, and significance thereof].

Objective: To study the clinical features and molecular genetics of acute monocytic leukemia (AML) after orthotopic liver transplantation and significance thereof.

Methods: The clinical manifestations, laboratory findings, development, diagnosis, treatment, and prognosis of the first case of AML after orthotopic liver transplantation in the world, a Chinese, male, aged 46, were observed. RT-PCR was used to analyze the mRNA expression of FLT3, Pim-1, and Hsp-70 in the bone marrow mononuclear cells (BMMCs) of the patient.

[Clinical analysis of histocytic necrotizing lymphadenitis].

Objective: To understand the clinical features and histopathology of histocytic necrotizing lymphadenitis (HNL) so as to better recognize the disease.

Methods: The clinical features, histopathology, and diagnosis of 10 patients admitted to our hospital were retrospectively analyzed.

Results: The clinical features of these 10 cases included: young females were the majority; lymphadenopathy and fever were the most common clinical manifestations; some cases were accompanied by connective tissue diseases.

Antitumor effects of celecoxib on K562 leukemia cells are mediated by cell-cycle arrest, caspase-3 activation, and downregulation of Cox-2 expression and are synergistic with hydroxyurea or imatinib.

Celecoxib, a specific cyclooxygenase-2 (Cox-2) inhibitor, has been shown to possess antitumor activity in a variety of cancer cells. However, the antitumor activity of celecoxib in hematopoietic tumors, especially in chronic myeloid leukemia (CML), has not been well established. This study was designed to investigate the effect of celecoxib on growth and apoptosis in a human CML cell line (K562 cells) or in primary CML cells, and to examine the synergistic actions of celecoxib and hydroxyurea or imatinib on K562 cell proliferation and apoptosis.

Myelodysplastic syndrome with transformation to acute monocytic leukemia with FLT3-ITD mutation following orthotopic liver transplantation.

A rare case of a 46-year-old man who underwent myelodysplastic syndrome, acute monocytic leukemia with FLT3-ITD mutation and splenic disruption following orthotopic liver transplantation is reported. The study of this case may be helpful to understand both the pathogenesis of acute leukemia and new complication of liver transplantation.

[The dynamic analysis and the clinical significance of vascular endothelial cell markers and hemolysis parameters in thrombotic thrombocytopenic purpura].

Objective: To monitor the changes of hemolysis parameters and endothelial cell markers in thrombotic thrombocytopenic purpura (TTP) and reveal the clinical significance of these changes.

Methods: vWF-cleaving protease (vWF-CP) activity in 3 cases of TTP was detected by Western blot. The percentages of fragmented red cells (FRC) were counted throughout the entire clinical course.

[The activation of JAK/STAT signal pathway in hypereosinophilic syndrome and the patients therapeutic response to imatinib].

Objective: To determine whether JAK/STAT pathway is involved in proliferation of hypereosinophilic syndrome (HES) cells, and reveal the pathogenesis of HES; observe the dynamic change of the clinical phenotype and hematological response, the expression of janaus kinase/signal transducer and activator of transcription (JAK/STAT) protein or FIP1L1-PDGFRA mRNA in one HES patient treated with low-dose imatinib.

Methods: The granulocytes of peripheral blood of 4 HES patients, including 3 FIP1L1-PDGFRA positive cases and 1 negative case, were collected. The expression of JAK2, STAT3, and phosphorylated STAT (P-STAT5) proteins were detected by western blotting.

[Identification of FIP1L1-PDGFRA fusion, and expression of signal transducer and activator of transcription 5 in hypereosinophilic syndrome].

Objective: To determine whether FIP1L1-PDGFRA fusion exists in hypereosinophilic syndrome (HES) patients, explore the relationship between FIP1L1-PDGFRA fusion and clinical phenotypes, and observe and reveal the expression of signal transducer and activator of transcription 5 (STAT(5)) in granulocytes of HES and the biological significance thereof.

Methods: Specimens of peripheral blood were collected from 4 HES patients diagnosed based on the criteria of Chusid et al. Total RNA was extracted from granulocytes and cDNA was synthesized by reverse transcription.

Upregulation and activation of caspase-3 or caspase-8 and elevation of intracellular free calcium mediated apoptosis of indomethacin-induced K562 cells.

Background: A nonsteroidal anti-inflammatory drug, indomethacin, has been shown to have anti-leukemic activity and induce leukemic cell apoptosis. This study was to elucidate the mechanism of indomethacin-induced K562 cell apoptosis.

Methods: K562 cells were grown in RPMI 1640 medium and treated with different doses of indomethacin (0 micromol/L, 100 micromol/L, 200 micromol/L, 400 micromol/L, 800 micromol/L) for 72 hours.

[Heparin cofactor II (HCII) activity and antigen assay and their significance in thrombotic diseases].

Objective: To study the plasma HCII activity and antigen level variations and their relationship with arterial and deep venous thrombotic diseases.

Methods: Seventy-five patients with brain infarction (BI), 50 myocardial infarction (MI), 36 deep venous thromboembolic disease (DVT) and 50 healthy controls were entered in this study. Plasma HCII activity was measured with chromogenic substrate method and the HCII antigen level by Western blotting assay.

[High-performance liquid chromatographic assay for plasma total homocysteine].

Objective: To establish a high-performance liquid chromatography (HPLC) assay with an internal standard for determining plasma total homocysteine.

Methods: The Hcy-mixed disulfides or protein bound Hcy in the plasma were reduced with TCEP. Subsequently, the thiol-compounds in the samples were derivatized with a thiol-specific fluorogenic reagent, SBD-F.