Blood Platelets/*drug effects ; Blood Platelets/enzymology ; Cholinesterase Inhibitors/*adverse effects ; Models, Animal ; Movement/*physiology ; Platelet Aggregation/*drug effects ; Pyridostigmine Bromide/*adverse effects ; Work/*physiology

The purpose of study was to investigate the ultrastructural features of leukemic megakarocyte (LMK) in patients with acute megakaryocytic leukemia (M(7)). Analyzing the ultrastructure characteristics of LMK and positive ratio of platelet peroxides (PPO) in 11 patients with M(7) were analyzed on basis of transmission electron microscopic observation retrospectively. The results showed that the diameter of LMK in 7 out of 11 cases was less than 20 microm, in 2 cases of them, the LMK diameter was from 10 to 15 microm and their PPO positive ratio was more than 50%, most LMK displayed regular shape, less protrusions, irregular nucleus, high nuclear/cytoplasm ratio, tiny granules, undeveloped demarcation membrane system (DMS) and irregular tubules in cytoplasm; in 5 out of those 7 cases the diameter of LMK was about 20 microm, PPO positive cell count was from 8% to 22%, most showing round or horseshoe nuclei, more or less heterochromatin, no DMS and granules were found in LMK in 3 cases and 2 cases occasionally. In other 5 out of 11 cases, the diameter of LMK was from 20 to 40 microm and PPO positive ratio was from 16% to 80%, in which smaller LMKs were similar to those in former cases in shape, and the larger LMK had irregular protrusions, varied nuclear/cytoplasm ratio, more heterochromatin, prominent nucleolus, some of them contained developed DMS, tubules and alpha-granules. It is concluded that most patients with M(7) are predominant of LMK in stage-I and minority contained LMK in II or III stage simultaneously. The differentiation degrees of LMK are different in individual and various cases.
Adult ; Blood Platelets ; enzymology ; Child, Preschool ; Female ; Humans ; Infant ; Leukemia, Megakaryoblastic, Acute ; pathology ; Male ; Megakaryocytes ; ultrastructure ; Middle Aged ; Peroxidase ; blood ; Retrospective Studies ; Young Adult

OBJECTIVETo analyze the ultra microstructures and the expression of platelet peroxidase (PPO) of megakaryocytes from bone marrow, their clinical manifestations and laboratory characteristics in patients with acute megakaryoblastic leukemia (AMKL).

METHODSKaryocytes from bone marrow of 22 AMKL patients were divided into two parts by lymphocyte separation liquid, one part was used to prepare the ordinary transmission electron microscope specimens to observe the morphological structures of megakaryocytes, the other was used to prepare the histochemical specimens of platelet peroxidase to analyze the positive reaction of PPO in AMKL, which were coupled with the patients' data of with bone marrow morphology, cell chemistry, and chromosome karyotype examination.

RESULTSMegakaryocytes from 17 of 22 patients were in the first stage, less than 20 µm in diameter, the nucleis were round, the cytoplasm contained microtubules, membranous vesicles and minute dense granules, no demarcation membrane system and surface-connected canalicular system, less dense granules and α-granules; Megakaryocytes in 5 cases were mainly in the first stage, while containing second and third stage megakaryocytes; the positive rate of PPO in megakaryocytes of 22 patients was 0-80%. The primitive and naive megakaryocytes were found in bone marrow smears of 22 cases, CD41 staining of the megakaryocytes was detected in the primitive and naive megakaryocytes, and more complex chromosome karyotype anomalies were observed.

CONCLUSIONThe majority of megakaryocytes in AMKL patients were the first stage ones, the rest were second and third stage ones, and the positive PPO reaction was significantly different. CD41 staining of the megakaryocytes was specific with complex chromosome karyotypeswere.

Blood Platelets ; enzymology ; Bone Marrow ; pathology ; Cell Count ; Chromosome Aberrations ; Chromosome Disorders ; Humans ; Karyotyping ; Leukemia, Megakaryoblastic, Acute ; diagnosis ; pathology ; Megakaryocytes ; pathology ; Peroxidase ; metabolism ; Staining and Labeling

This study was aimed to detect the biomaterial-induced phosphorylation level of platelet focal adhesion kinase, a key component of signal transduction pathways. Flat tubings, made from 5 biomaterials: organotin-PVC, PU50, PU60, PU70, and PTFE,were connected to an ex vivo flow circuit with canine femoral artery and vein. After 5 min, the adherent platelets on the inner surface of the tubing were lysed, then FAK and phospho-FAK were examined, using immunoprecipitation and Western blot. The results showed a significant increase in the FAK value on the PVC and PTFE surface,compared to the PUs; among the PUs, the FAK value decreased in the following order: PU70/PU60/PU50. The phospho-FAK value on the five groups of surface decreased in the following order: PVC/PTFE/PU70, PU60, PU50; there was no significant difference among the PUs with regard to the phospho-FAK value. In conclusion, after platelet-material interaction, biomateriais may lead to the phosphorylation of FAK of platelets;the level of phosphorylation of FAK has been positively linked to the thrombogenicity of materials; the phospho-FAK value may be a valid molecular parameter of the haemocompatibility assessment; the FAK value may supply references to the haemocompatibility assessment.
Animals ; Biocompatible Materials ; chemistry ; Blood Platelets ; enzymology ; Dogs ; Femoral Artery ; surgery ; Femoral Vein ; surgery ; Focal Adhesion Protein-Tyrosine Kinases ; chemistry ; Materials Testing ; Phosphorylation

Blood Platelets ; enzymology ; Diabetes Mellitus, Type 2 ; enzymology ; Enzyme Activation ; Humans ; Hydroxymethylglutaryl-CoA Reductase Inhibitors ; pharmacology ; Nitric Oxide Synthase ; metabolism ; Nitric Oxide Synthase Type III ; Phosphorylation ; Pravastatin ; pharmacology ; Serine ; metabolism

BACKGROUNDBone marrow hematopoietic function suppression is one of the most common side effects of chemotherapy. After chemotherapy, the bone marrow structure gets destroyed and the cells died, which might cause the hematopoietic function suppression. Heme oxygenase-1 (HO-1) is a key enzyme of antioxidative metabolism that associates with cell proliferation and resistance to apoptosis. The aim of this study was to restore or resist the bone marrow from the damage of chemotherapy by the HO-1 expression of mouse mesenchymal stem cells (mMSCs) homing to the mice which had the chemotherapy-induced bone marrow suppression.

METHODSOne hundred and sixty female Balb/c mice (6-8-weeks old) were randomly divided into four groups. Each group was performed in 40 mice. The control group was intraperitoneally injected for 5 days and tail intravenously injected on the 6th day with normal saline. The chemotherapy-induced bone marrow suppression was established by intraperitoneally injecting cyclophosphamide (CTX) into the mice which performed as the chemotherapy group. The mMSCs were tail intravenously injected into 40 chemotherapically damaged mice which served as the mMSCs group. The difference between the HO-1 group and the mMSCs group was the injected cells. The HO-1 group was tail intravenously injected into the mMSCs that highly expressed HO-1 which was stimulated by hemin. The expression of HO-1 was analyzed by Western blotting and RT-PCR. Cell proliferation was measured using the 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. Histopathologic examinations were performed 1 week after injection.

RESULTSCompared with the control group, the expression levels of HO-1 mRNA and protein were significantly higher in the HO-1 group (all P < 0.05), even obviously than the mMSCs group. CTX treatment induced apoptosis and inhibited proliferation. After injected, the white blood cell (WBC), red blood cell (RBC) and platelet (PLT) declined fast and down to the bottom at the 7th day. The bone marrow structure was destroyed incomplete. In vitro, the survival rate of cells in chemotherapy group was less than 50% after 24 hours. In contrast, mMSCs could do a favor to the cellular cleavage and proliferation. They slowed down the cell mortality and more than 50% cells survived after 24 hours. The effects of blocking apoptosis and bone marrow recovery could be more effective in the HO-1 group. In the HO-1 group, it had observed that the bone marrow structure became complete and the hemogram closed to normal at 7th day.

CONCLUSIONSHO-1 played an important role in promoting the recovery of CTX-induced hematopoietic damage. We suggest that HO-1 is able to restore the functions of chemotherapy-induced hematopoietic damage.

Animals ; Apoptosis ; drug effects ; Blood Platelets ; drug effects ; Blotting, Western ; Bone Marrow ; drug effects ; enzymology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cyclophosphamide ; toxicity ; Erythrocytes ; drug effects ; Female ; Heme Oxygenase-1 ; genetics ; metabolism ; Leukocytes ; drug effects ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; enzymology ; physiology ; Mice ; Mice, Inbred BALB C ; Reverse Transcriptase Polymerase Chain Reaction