bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Irreversible and Reversible Direct Thrombin Inhibitors and Danaparoid on Tissue Factor Mediated Thrombin Generation.
Authors: Samama Meyer M. , Le Flem Lena , Pierre-Eugène Daphne , Depasse Francois 
Published: October 2019

Abstract
Background
Recently, direct thrombin inhibitors such as Hirudin, Bivalirudin, Melagatran and Argatroban have been introduced in the armamentarium of an antithrombotic drugs. Danaparoid, an anti-Xa - anti IIa agent is also used especially in Heparin induced thrombocytopenia.
Objective
Thrombin generation test (TGT) has been recently automated and could be useful for the evaluation of the inhibitory activity of these drugs and the measurement of their anticoagulant effects at established therapeutic concentrations. Moreover, TGT can elucidate some information about their mechanism of action.
The aim was to compare Hirudin, Argatroban, Melagatran and Danaparoid while Bivalirudin was not available.
Methods and results
Pools of normal human plasma were spiked with increasing concentrations of the four studied drugs and TGT was determined by studying the lag time (LT) and time to peak TTP as well as the peak (P), the endogenous thrombin potential (ETP) and the mean rate of thrombin generation (velocity TG) and its inhibition once a maximal concentration has been reached (velocity TI). The mechanism of action on TGT was heterogeneous. At therapeutic concentrations, Hirudin delays dramatically thrombin generation without affecting significantly its velocity and the amount of thrombin formed.
Argatroban and Melagatran induce a far less marked prolongation of LT and TTP than hirudin but they both reduce the velocity of the reaction and the amount of thrombin generated in this in vitro study. Melagatran was found more active than Argatroban but the patterns of the thrombograms were similar.
Danaparoid exerts a minimal effect on LT and TTP which is associated with a very significant influence on the parameters related to the reaction of thrombin formation (velocity index, peak and ETP). In total ETP generally considered as the most informative parameter of the thrombogram was not found as relevant as predicted. Schematically, 3 different patterns for the thrombogram have been observed indicating different mechanisms of anticoagulation, all of them, clearly associated with an antithrombotic activity in vivo.
Conclusion
The mechanism of action of hirudin on thrombin generation is clearly different from that of Argatroban, Melagatran and Danaparoid. This work demonstrates that antithrombotic activity is associated with different alterations of TGT. The results could help to determine the blood concentrations required for an effective anticoagulation or reciprocally the alterations of the thrombogram which are associated with therapeutic efficacy. Moreover they could be useful when laboratory monitoring of the treatment with these different drugs is considered.
Antiplatelet Agents as Secondary Thromboprophylaxis after Anticoagulant Treatment for Thrombosis.
Authors: Papaioannou Georgia , Papadakis Emmanouil , Topalidou Maria , Kokoviadou Kyriaki , Karapiperidou Anastasia , Kioumi Anna , Korantzis Ioannis 
Published: October 2019

Abstract
Patients suffering an unprovoked VTE event have high risk of recurrence after anticoagulation cessation especially in the first two-year period. Our study examined whether secondary thromboprophylaxis with antiplatelet drugs reduces the relapse risk.
STUDY DESIGN: We studied 53 patients, 25 men and 28 women, (group A), with median age of 41(18–74) years. 31 received aspirin at 100mg while 22 received clopidogrel at 75mg after anticoagulant therapy for VTE. We compared them with 77 patients (group B) who did not receive any thromboprophylaxis after VTE with a median age of 40(18–82) years. Of group B, 56 were men while 21 were women. In 51 out of 130 patients we monitored D-dimers, F1+2 prothrombin fragments, and TAT (thrombin-antithrombin) complexes as prothrombotic and fibrinolysis markers. Failure was determined as VTE recurrence or elevation of prothrombotic markers in the first 2year period.
RESULTS: In 4 patients of group A (7,5%) we noticed marked elevation of prothrombotic markers and they were turned to anticoagulation, and in 3 marker elevation subsided by changing the antiplatelet agent (aspirin to clopidogrel). 1 patient stopped prophylaxis due to hemorrhage while none relapsed. In group B VTE recurrence was noticed at 27(36%, p<0,0002). In both groups late recurrence (> 2 years) was observed at 27,6% of 130 patients.
CONCLUSIONS: Low dose aspirin or clopidogrel administration is safe and effective as thromboprophylaxis after anticoagulation for first venous thromboembolic event. Markers as D-dimers, F1+2, TAT, have prognostic significance and are valuable tools in patient monitoring. Patient follow-up has to be long-standing because VTE recurrence risk persists through the years.
Bcl-2 Family Protein Inhibitors Induce a Unique Thrombocytopenia In Vivo.
Authors: Elmore Steven W. , Bauch Joy , Fryer Ryan M. , Iciek Laurie , Marsh Kennan , Morgan Sherry J. , Nelson Richard , Reinhart Glenn A. , Smith Morey L. , Tse Chris , Rosenberg Saul H. 
Published: October 2019

Abstract
We recently disclosed the discovery of ABT-737, a potent antagonist of antiapoptotic Bcl-2 family proteins that induced tumor regression in murine xenograft models. ABT-263 is a related, orally bioavailable Bcl-2 family protein inhibitor that is currently in clinical development. For both agents, multiple daily dosing from two to four weeks was well tolerated in all species evaluated. The primary preclinical toxicological finding in mouse, rat and dog was a unique thrombocytopenia characterized by a rapid clearance of circulating platelets. A series of in vivo studies that were performed to better characterize this phenomenon are described here. After a single intravenous or oral dose in dogs, circulating platelet counts decreased rapidly and concentration dependently with a nadir at approximately six hours post administration. Platelet counts returned to near normal levels within several days post dose, accompanied by an increase in both mean platelet volume and percent of reticulated platelets. Analysis of platelets by aggregometry during this rebound period indicated that returning platelets were fully functional. Following multiple doses, platelet counts also decreased rapidly after initial dosing, but exhibited evidence of rebound during the dosing period that appeared to be dose dependant. Evaluation of fibrinogen, d-dimer, antithrombin-III, PT and APTT did not support a mechanism involving consumptive coagulopathy. Whole body scintography utilizing [111] Indium labeled platelets in dogs indicated that platelet clearance after compound administration is primarily mediated by the liver. These data suggest that ABT-737 and ABT-263 preferentially affect circulating platelets rather than abrogating platelet production in the bone marrow. In fact, the observed rebound in platelet count in the face of continued dosing reflects the capacity for the animals to compensate for the effect. The enantiomer of ABT-737 (which has significantly lower activity against Bcl-2 family proteins) had no effect on circulating platelets in animals suggesting an underlying mechanism that is dependent on inhibition of antiapoptotic Bcl-2 family proteins. The unusually rapid kinetics of platelet clearance and recovery suggests that the drug-induced thrombocytopenia elicited by these Bcl-2 family protein inhibitors is unique compared to that observed with conventional cytotoxic chemotherapy.
Expression of MTPG-24, a Peptide Derived from a Protein Regulating Dynamic Changes in Cortical Actin, Induces Endomitotic Replication in Megakaryocytic Cells.
Authors: Ste-Marie Alexandre , Simard Carl , Côté Serge 
Published: October 2019

Abstract
Prior to the fragmentation of their cytoplasm leading to platelet formation, differentiating megakaryocytes (MKs) increase their ploidy and cellular volume by undergoing repeated rounds of DNA replication without concomitant cell division, a process known as endomitosis. There is now accumulating evidence that endomitotic MKs develop as a result of aberrant regulation of the cleavage furrow formation, the site where dynamic changes in actin, myosin and membrane structure mediate the process of cytokinesis during animal cell division. Here we report that transfection of human megakaryocytic cell lines with vectors expressing a 24mer-peptide (MTPG-24) resulted in remarkable changes in morphology, resulting in cells with the appearance of mature polyploid megakaryocytes. MTPG-24 is derived from a protein involved in regulating actin-based structures and motility which possesses a putative site for PKA phosphorylation. Despite its hydrophilic primary structure, MTPG-24 fused to a fluorescent tag was detected closely associated to the plasma membrane where it accumulated in a punctuate pattern, in addition to co-localizing with a Golgi marker. Interestingly, in each recombinant clone, cells with different ploidy levels developed among normally dividing ones, suggesting that transit from a mitotic cycle to an endomitotic cycle seemed to only occur in cells having completed a given number of cell cycles. These effects were obtained independently of the nature of the tag fused to the peptide (Hemagglutinin, Orange protein, GFP) but were not observed with a control peptide in which the amino acids of MTPG-24 were disposed in an arbitrarily sequence. Because it possibly interferes with some effector molecules required for cleavage furrow membrane assembly in late anaphase, MTPG-24 provides thus a new tool for understanding the molecular basis of endomitosis. Furthermore, since there is a correlation between DNA content and the numbers of platelets released by MK, we are currently testing whether this peptide could be used to increase the ploidy level of CD34+ human cord blood-derived MKs which have a low propensity to become highly polyploid.
Differential Induction of Apoptosis in Human Leukemia Cells (ML-1, ML-2, CTV-1 and KASUMI-1) Exposed to the Proteasome Inhibitor Bortezomib and the Effect of Transforming Growth Factor-beta Signaling Pathway.
Authors: Fuchs Ota , Provaznikova Dana , Peslova Gabriela , Kocova Marcela , Marinov Iuri , Spicka Ivan 
Published: October 2019

Abstract
Bortezomib (N-pyrazinecarbonyl-L-phenylalanine-L-leucine boronic acid; VELCADE, formely known as PS-341 or MLN-341; Millenium Pharmaceuticals, Inc., Cambridge, MA) is a potent and specific proteasome inhibitor. It is the first member of proteasome inhibitors which obtained approval as chemotherapeutic agent for the treatment of relapsed or refractory multiple myeloma. First clinical experience of bortezomib in patiens with follicular lymphoma and mantle cell non-Hodgkin lymphoma suggest that bortezomib is well tolerated and has significant single-agent activity. Several phase I trials on the use of bortezomib as a novel treatment strategy in leukemia have been started. We studied the effect of of bortezomib and of transforming growth factor-beta (TGF-β) on induction of cell cycle arrest and apoptosis in human leukemia cells (ML-1, ML-2, CTV-1 and KASUMI-1) established from the peripheral blood of patients with acute myeloid leukemia (AML). [6-3H] thymidine incorporation was used as a measure of DNA synthesis to estimate cell proliferation. Apoptosis was detected by flow cytometry using annexin V-FITC/propidium iodide assay and results were confirmed by cell cycle analysis. The profiles of cellular DNA contents indicated the distribution of the cells in different phases of the cell cycle and any possible DNA loss due to DNA fragmentation during apoptosis. The cells with a DNA content less than that of G1 cells were considered as apoptotic cells. Statistical significance of the experimental results was analyzed by Student’s paired t-test. Leukemia cells were preincubated for 24–96 h without addition (control) or with bortezomib (4 nM or 10 nM) or with TGF-β1 (5 ng/ml or 10 ng/ml). TGF-β1 inhibited DNA synthesis only in KASUMI-1 cells but not in other leukemia cells used. Bortezomib (10 nM) was potent inhibitor of DNA synthesis in all four types of leukemia cells and induced apoptosis in KASUMI-1, ML-2 and CTV-1 cells but not in ML-1 cells [Figure 1]. Kinetics of apoptosis was different in individual cell lines. The peak of apoptosis was reached in 24 h in ML-2 cells, however in KASUMI-1 and CTV-1 cells in 48h. KASUMI-1 cells were most sensitive to bortezomib. In addition KASUMI-1 and ML-2 cells were also sensitive to induction of apoptosis by TGF-β1 but in lesser extent than by bortezomib [Figure 1]. Kinetics of apoptosis induction by TGF-β1 was slower than with bortezomib and lasted 48–96 h. Different sensitivity of human leukemic cell lines to bortezomib likely mimics behaviour of primary leukemic cells of patients and thus limits the use of proteasome inhibitors in therapy.
Figure 1 Figure 1.
Experimental Study of the Extract of Hedyotic Diffusa Willd on Induction of the Apoptosis of Leukemia U937 Cells.
Authors: Lin Shengyun , Ye Baodong , Hu Meiwei , Hu Zhiping , Yu Rongxi , Zhou Yuhong 
Published: October 2019

Abstract
Hedyotic Diffusa Willd (HDW) is a Chinese herbal medicine, it has the effect on heat-clearing and detoxicating, activating blood circulation to dissipate blood stasis, removing dampness and promoting diaresis and deturescence. It used for treating various kinds cancer generally for the past few years in china. According the different of solvent polarity, we had extracted the active components from HDW by various solvent (water, ethanol, acetidin, chloroform, alkane) and explored the effects of every active component from HDW on proliferation and apoptosis of leukemia U937 cells. It was found that ethanol extract showed the strongest antitumor effect. Exposured log phase growth U937 cells to different ethanol extract from HDW concentrations for different time respectively and then test the inhibitive effect by modified tertrozalium salt (MTT) assy. The apoptosis of HDW induced on U937 cells was detected by means of optics microscope, flow cytometry and gel electrophoresis of DNA. The antiproliferative effects were observed following exposure ethanol extract of HDW. It shows a very substantial differences in the dose and duration dependency of the observed antiproliferative and cytotoxic effects. The U937 cells treated by ethanol extract of HDW are observed apoptosis characteristic morphological changes such as complete cell membrane,nuclear fragmention apoposic bodies and found trapezoidal belt with DNA.When 0.5mg/ml, 1mg/ml, 2mg/ml, 4mg/ml ethanol extract of HDW treated U937 cells for 48 hours, the numbers of apoptotic cells were respectively 4.18%, 56.96%, 82.43%, 56.41%. These results indicate that Ethanol extract of HDW has the strongs antitumor and inhabited the proliferation and induced the apoptosis of U937 cells stignificantly.
Fluorescence Quantitative PCR Detection of FLT3 Gene Expression in Leukemias and Its Clinical Implications.
Authors: Xu Bing , Tang Jiahong , Li Lin 
Published: October 2019

Abstract
Objective In order to study the clinical significance of the FLT3 expression level in AML patients.
Methods we analyzed the expression level of the FLT3 transcript quantitatively by real time fluorescence quantitative PCR amplification and investigated correlations with FLT3/ITD gene mutation in 69 de novo AML cases.
Results The mean of FLT3 transcripts in the 69 AML patients was 17240 copies/μgRNA(273~834805), which was significantly higher in AML cases than in healthy donors (p=0.017). The FLT3 expressions were not equally distributed among the FAB subtypes(P=0.0005). The leukocyte counts was significantly related to FLT3 expression (P=0.0001 and r=0.4494). There were noticeable deviation among karyotypes in the expression of FLT3. The expression of cases with t(15;17) was lower that that of cases with t(11q23) and complex karyotypes. There was no significant difference of FLT3 mRNA between patiens positive and negtive for CD34 (P=0.315). FLT3/ITD gene mutation was observed in 17 of total 69 cases with AML(24.6%). There was no significant difference of FLT3 mRNAamong FLT3/ITD positive and negtive patients (P=0.205) and there was no significant difference of CR rates in high-FLT3-expression and low-FLT3-expression groups after chemical theropy(P=0. 425). During the follow-up of 210 days(median day=124), there was no significant difference of the cumulative relapse rates between these two groups (P=0.631).
Conclusion The expression of FLT3 gene was significantly higher in patiens with AML than in healthy donors and had a positive correlation with peripheral white blood cells counts. There was statistic difference among various FABs and karyotypes. FLT3 mRNA level in AML patients had no correlation with the expression of CD34 and FLT3/ITD gene mutation. In the short-term follow-up, high expression of FLT3 had no influence on CR, CRR and OS of AML patients.
Classical and Molecular Cytogenetic Abnormalities in 124 Pediatric Patients with Acute Lymphocyte Leukemia.
Authors: Chai Yihuan , Lv Hui , Lu Jun , Xiao Peifang , Li Jianqing 
Published: October 2019

Abstract
In childhood acute lymphocyte leukemia (ALL), cytogenetics plays an important role in diagnosis, allocation of treatment and prognosis. On base of the conventional cytogenetic analysis, molecular methods have inproved our ability to accurately and rapidly risk-stratify patient with childhood ALL in the last few years. Our aim was to assess the demography of cytogenetic abnormalities in childhood ALL. The study sample consisted of 124 newly diagnosed ALL patients younger than 16 years, who were diagnosed at the Department of Pediatric Hematology/Oncology, Soochow University Children’s Hospital. The diagnosis and FAB subtypes of ALL was determined by Wright-Giemsa-stained bone marrow smears and cytochemicalstaining. Immunophenotyping of the bone marrow samples was performed by flow cytometry. Multiplex reverse transcription-polymerase chain reaction (RT-PCR) analysis was performed to detect the 29 most common leukemia translocations for routine molecular diagnostic hematopathology practice, and complement the information gained from conventional cytogenetic analysis. Cytogenetic analysis was successful in 112 of 124 children with ALL. Sixty-eight (60%)of them had clonal chromosomal abnormalities. Numerical imbalances consisted of hyperdipoild(>47 chromosomes, 36 cases), hypodipoild(<46 chromosomes, 14 cases), pseudodiploidy(18 cases). Chromosomal translocations were observed in 13 patients by conventional cytogenetic analysis. Three cases were found positive for t (4;11), 3 cases for t (9;22), 1 case for t (1;19) and 6 cases for other rare translocations. RT-PCR analysis detected 116 of the 124 ALL patients. Thirteen cases of TEL-AML1, 10 cases of rearrangement in the MLL gene, 4 cases of E2A-PBX1, 4 cases of E2A-HLF, 3 cases of BCR-ABL, 2 cases of TLS-ERG, 32 cases of HOX11, were detected by RT-PCR in B-lineage leukemias. SIL-TAL1 had been found in 4 of 7 of T-lineage leukemias. Sixty-eight cases of ALL show chromosomal aberrations. Multiplex PCR positivity was detected in 59(50%)of the 116 ALL patients studied. Multiplex PCR combined with chromosome analysis uncovered Chromosomal abnormalities in 95 of 124(77%) of ALL patients and supplemented each other in detecting Chromosomal abnormalities. It provides reliable evidence for the diagnosis, classification and prognosis.
Clinico-Biological Characteristics and Prognosis of Non-M3 Acute Myeloid Leukemia with High Percentage of Myeloperoxisase Positive Blasts. Single Center Experience.
Authors: Montesinos Pau , Algarra Lorenzo , Sanz Jaime , Perez Mari Luz , Senent Leonor , Sempere Amparo , Gomis Federico , Cantero Susana , Martinez Jesus , Lorenzo Ignacio , Sanz Guillermo , Sanz Miguel 
Published: October 2019

Abstract
Introduction: It has been suggested that acute myeloid leukemia (AML) showing mature phenotype is associated with favourable outcome. In a study recently published by JALSG, myeloperoxidase (MPO) positivity in over 50% of blasts had favourable prognostic impact, independent from karyotype, on achieving complete remission (CR), overall survival (OS) and disease free survival (DFS). No other studies have established the independent prognostic value of MPO expression.
Objectives: Analyze the clinico-biological characteristics of AML with high percentage of MPO+ blasts and its impact on CR, OS and DFS.
Material and methods: Between 1986 and 2005, 418 adult patients (median 53 years, range 15–80) were diagnosed with de novo non-APL AML and evaluated for percentage of MPO+ blasts. All patients received intensive chemotherapy. Diagnosis was made by optic microscopy of bone marrow (BM) aspirates stained with May-Grumwald giemsa, MPO, butyrate esterase and or non specific esterase. Cytogenetic and immunophenotype analysis was evaluated in 66% and in 76% of the cases respectively.
Results: 118 patients (28%) showed a percentage of MPO+ blasts >75%. AML with MPO+ blasts >75% was associated with M1-M2-M4 subtypes, leucocytes >50×109/L, blasts in BM >70% and HLA-DR negativity (p<0.01). It was also significantly associated with favourable karyotype (11% vs 3% favourable, 52% vs 48% intermediate and 3% vs 15% unfavourable). Patients with AML and MPO+ blasts >75% obtained higher CR rate (71% vs 55%), due to less resistant disease (9% vs 22%, p<0.01). In multivariate analysis favourable karyotype, leukocytes <50×109/L and age <60 were favourable prognostic factors for CR. Median OS and DFS was higher in patients with AML and MPO+ blasts >75% (15 vs 7 months, p<0.001, y 41 vs 12 months, p<0.001, respectively). ). In multivariate analysis, favourable karyotype, leukocytes <50×109/L, age <60 years and MPO+ >50% were favourable prognostic factors for OS; and age <60 and MPO+ >75% were the only independent factors for DFS. Median DFS was higher in patients with AML and MPO+ blasts >75% in the intermediate cytogenetic risk group (59 vs 13 months, p=0.015), age <60 (109 vs 15 months, p=0.003), age >60 (13 vs 7 months, p=0.03), autologous stem cell transplantation (100 vs 9 months, p=0.04) and chemotherapy alone (16 vs 8 months, p=0.003).
Conclusion: In our series, patients with AML and MPO+ blasts >75% show less chemoresistant disease and a longer remission duration, the latter independently from the karyotype. This biological characteristic could be useful in designing therapeutic strategies in patients that lack other prognostic markers.