bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effects of Imatinib on the Function of Monocyte Derived Dendritic Cells Are Mediated Via the Inhibition of Akt and NF-kappaB Signal Transduction Pathways.
Authors: Rupf Anette , Appel Silke , Weck Markus M. , Grünebach Frank , Kanz Lothar , Schoor Oliver , Brümmendorf Tim H. , Weinschenk Toni , Brossart Peter 
Published: October 2019

Abstract
Imatinib is a novel tyrosine kinase inhibitor effective against Abl kinases, c-Kit and platelet-derived growth-factor receptor (PDGF-R) and is currently used for the treatment of patients with CML and GIST. However, little is known about the effects of imatinib on function and differentiation of non-transformed normal cells. Using this compound, we show that human monocyte derived DC generated in the presence of therapeutic concentrations of imatinib show a concentration dependent reduced expression of CD1a, HLA and co-stimulatory molecules as well as decreased activation-induced secretion of chemokines and cytokines involved in T cell activation. Moreover, exposure to imatinib reduces the capacity of DC to prime T cell responses that cannot be restored by the addition of IL-12 and which is not due to induction of apoptosis or IL-10 secretion. Using Western blot analyses we found that these effects are mediated by a pronounced downregulation of nuclear localized protein levels of NF-kB family members RelB, RelA and NF-kB p50. Furthermore, imatinib treatment inhibited the phosphorylation of Akt, indicating the involvement of the PI3 kinase pathways while not affecting the phosphorylation state of p38 and ERK1 MAP kinase. In line with these results, incubation of monocytes with PI3 kinase inhibitors resulted in a similar phenotype of DC as described above. Gene expression profiling utilizing DNA microarrays revealed upregulation of lysosomal genes and molecules preferentially expressed in monocytes/macrophages. However, in contrast to these observations, imatinib treatment had no effect on the incorporation of latex beads by DC and resulted in a reduced FITC-labeled dextran uptake. Importantly, utilizing blocking antibodies and tyrosine kinase inhibitors we demonstrate that the inhibitory effects of imatinib on DC differentiation are not mediated by PDGF-R and c-Kit but most likely via c-Abl tyrosine kinase. These results demonstrate that imatinib affects the antigen presenting function of DC on several levels: their phenotype, antigen uptake and processing as well as production of cytokines and chemokines.
Long Term Follow-Up of Patients with Hairy Cell Leukemia (HCL).
Authors: Ravandi-Kashani Farhad , Kantarjian Hagop , Faderl Stefan , O’Brien Susan , Thomas Deborah , Koller Charles , Cortes Jorge , Pierce Sherry , Keating Michael , Estey Elihu 
Published: October 2019

Interferon-a (IFN-a) and, more recently, nucleoside analogs (NA) such as 2-CDA and pentostatin have been used with significant success to treat HCL. A single course of 2-CDA produces response rates over 75%, with responses maintained for 4 years in 75% of pts. Similar results have been observed with pentostatin. (Dearden et al, Br J Haematol1999;106:515). To learn more about long-term outcome, we reviewed 234 pts with untreated HCL seen at the MDACC over a 30-year period; their median follow-up was 122 months from diagnosis (up to 387 months). Their median age at diagnosis was 50 years (range 23–83 years). Survival was superior among the 173 pts given either 2-CDA (n = 161) or pentostatin (n = 12) compared to those never given either NA (p = 0.042).
Figure Figure
Relapse occurred in 32 of 176 pts who received 2-CDA as their first chemotherapy either at MDACC or before presenting to MDACC. Therapy for relapse after 2-CDA included rituximab (N=9), a second course of 2-CDA (n=9), a second course of 2-CDA followed by rituximab (n=8), and other (n=6). No statistically significant differences in survival were seen possibly due to small pt numbers. The estimated 10-year and 20-year survival (from diagnosis) for the 176 pts who received 2-CDA as first chemotherapy was 84%, and 65%, respectively.
Figure Figure
The majority of pts who died were not in remission at time of death and thus presumably died of HCL. Hence alternatives to NA are needed in at least some pts, and we are evaluating whether covariates exist that might distinguish pts who do and do not relapse and, among the former, pts whose remissions are short. Pending identification of the latter and keeping in mind the length of the average remission, alternatives to NA should have very little toxicity. We have begun to add rituximab to 2-CDA to lengthen remission duration and thus extend survival in pts with untreated HCL.
A New Method of Retroviral Lineage Specific Expression Utilizing the Cre/lox System Induces a T-Lymphoid Malignancy in a Mouse Model of ALCL.
Authors: Miething Cornelius , Grundler Rebekka , Mugler Claudia , Peschel Christian , Duyster Justus 
Published: October 2019

Abstract
A t(2;5) (p23;q35) chromosomal translocation can be found in more than 50% of all cases of anaplastic large cell lymphoma (ALCL), which belong to the group of aggressive Non-Hodgkin-Lymphomas (NHL). The fusion of the nucleophosmin gene (NPM) on chromosome 5 to the anaplastic lymphoma kinase (ALK) on chromosome 2 leads to a deregulated, constitutively active kinase which has been shown to play an important role in lymphomagenesis of ALCL. Mouse models, where the NPM-ALK fusion oncogene is retrovirally expressed in whole bone marrow (BM) cells which are subsequently transplanted into lethally irrradiated recipients have shown that NPM-ALK is able to induce histiocytic and plasmacytoid malignancies. Since ALCLs are in the vast majority either of T- or ‘Null’-cell phenotype, we have now developed a murine model of T-lymphoid ALCL. By employing a retroviral vector incorporating a translational stop-cassette flanked by loxP recombination sites recognized by the Cre recombinase, we established a new method of lineage specific gene expression in-vivo. We tested the vector by infecting BM cells harvested from mice expressing Cre from different lineage specific promotors. We have infected BM cells from mice expressing Cre under the control of the lysozyme M-promotor (lysM-mice), which is active in the myeloid compartment, from mice expressing Cre from the granzyme B-promotor (GrzmB-mice), which is mainly active in T-cells, and finally we also used BM cells from C57B6 wildtype mice as a control. Mice transplanted with BM from lysM-mice succumbed to a histiocytic malignancy after 4–6 weeks, whereas mice transplanted with BM from GrzmB-mice developed a mixed T-NHL/histiocytic phenotype with a similar latency. These mice displayed infiltration of malignant, mostly CD4/CD8 DP T-cells in the thymus, lymphnodes and spleen, as well as a histiocytic infiltration in the spleen and BM. Mice transplanted with control BM from wt mice did not show signs of disease after up to 6 months. The results indicate that the hematopoetic lineage where an oncogene is expressed is paramount to the malignant phenotype
The described model represents a versatile tool for the analysis of NPM-ALK signaling pathways in-vivo. With the help of this method, any gene can be rapidly expressed in a defined lineage or in a developmental stage. Thus, also more subtle phenotypes may become amenable to investigation in-vivo.
Survival Factor Stimulates ERK-Dependent Phosphorylation of BIM Inhibiting Its Association with BAX and Pro-Apoptotic Activity.
Authors: Harada Hisashi , Quearry Bonnie , Korsmeyer Stanley J. 
Published: October 2019

Abstract
Growth factors and cytokines signal survival through their cognate receptors, activating signaling pathways often composed of protein kinase cascades. On the other hand, inadequate growth factor initiates a signaling cascade that leads to cell death. Both pro-and anti-apoptotic BCL-2 family members lie downstream of these proximal signals. The “multi-domain” BCL-2 members either suppress (e.g., BCL-2, BCL-XL) or promote apoptosis (e.g., BAX, BAK), whereas the “BH3-only” subfamily members identified to date (e.g., BAD, BID, BIM) function to promote cell death. It has become clear that BH3-only proteins are upstream initiators of apoptosis. BIM was identified as a BH3-only protein that induces apoptosis and can be antagonized by anti-apoptotic BCL-2 family members. Studies in BIM-deficient mice/cells indicate important roles for BIM in hematopoietic cell homeostasis. In the present study, an siRNA knockdown of BIM confirms this BH3-only member is important for the cytokine-mediated homeostasis of hematopoietic cells. We show that the phosphorylation status of BIM controls its pro-apoptotic activity. Interleukin-3 (IL-3), a hematopoietic survival factor, induces ERK/MAPK-mediated phosphorylation of BIM on three serine sites (Ser55, Ser65, Ser100). IL-3 withdrawal results in the dephosphorylation of BIM and only non-phosphorylated BIM interacts with the multi-domain pro-apoptotic effector BAX. Phosphorylation of BIM upon exposure of cells to IL-3 dramatically reduces the BIM/BAX interaction. A non-phosphorylatable BIM molecule (S55A, S65A, S100A) demonstrates enhanced interaction with BAX and enhanced pro-apoptotic activity. Thus, ERK/MAPK-dependent phosphorylation of BIM in response to survival factor regulates BIM/BAX interaction and the pro-death activity of BIM.
Post-Thrombotic Syndrome, Functional Disability and Quality of Life after Upper Extremity Deep Venous Thrombosis in Adults.
Authors: Kahn Susan R. , Elman Elyssa , Bornais Chantal , Blostein Mark , Wells Philip S. 
Published: October 2019

Abstract
Background: The post-thrombotic syndrome (PTS) after upper extremity deep venous thrombosis (UEDVT) has not been well characterized.
Objectives: To describe and quantify residual symptoms, functional disability and quality of life associated with post-thrombotic syndrome after UEDVT in adults.
Methods: Twenty-four patients with objectively diagnosed UEDVT (bilateral in 1 patient) at least 6 months previously were recruited from two thrombosis clinics in Canada (Montreal and Ottawa). Data were collected by interview and chart review on demographic characteristics, DVT risk factors and affected venous segments. The Villalta PTS scale, modified for the upper extremity, was used to diagnose PTS and to quantify its severity (score >4=PTS; score >14=severe PTS). Patients completed questionnaires on type and severity of symptoms, degree of functional disability (DASH questionnaire) (higher scores=greater disability), and generic (SF-36) and disease-specific (VEINES-QOL) quality of life (lower scores=worse QOL). Results of these measures were compared in patients with and without PTS.
Results: The mean age of study patients was 51 years and 54% were female. The average time since diagnosis of UEDVT was 13 months and median duration of warfarin treatment was 5 months. At the time of assessment, daily ipsilateral arm or hand swelling was reported by 52% of patients and daily ipsilateral arm pain by 20% of study patients, compared with 0% and 0%, respectively, in the contralateral arm. PTS was present in 11/25 (44%) limbs (11/24 patients). One patient had severe PTS. Patients with PTS had significantly higher mean DASH scores than those without PTS (23.3 vs. 3.9, p= 0.009) and poorer quality of life than those without PTS (mean VEINES-QOL score 45.6 vs. 53.6; p=0.001; mean SF-36 Physical Component Score (PCS) 40.8 vs. 50.2; p= 0.12). Although the overall frequency of PTS did not differ according to whether the initial UEDVT was in the dominant arm, PTS scores were higher and quality of life was poorer when PTS involved the dominant arm.
Conclusion: PTS occurs frequently after UEDVT at a rate that is similar to that of lower limb DVT. PTS of the upper extremity is associated with significant functional disability and has a measurable, adverse impact on quality of life. Patients with dominant arm PTS appear to fare worse than those with non-dominant arm PTS. Larger, prospective studies to identify prognostic factors that lead to PTS after UEDVT are warranted.
Megakaryocyte Specific Cre Transgenic Mouse.
Authors: Gushiken Francisca C. , Adachi Roberto , Lopez Jose A. 
Published: October 2019

Abstract
Here we report the first animal model with specific expression of Cre recombinase in megakaryocytes. Cre is an enzyme from bacteriophage-P1 that catalyzes reciprocal DNA recombination between pairs of loxP sites that results in excision of the DNA fragment located between them. The expression of Cre can be genetically manipulated by tissue specific promoters. When a tissue specific Cre mouse is crossed with a mouse line who has a gene flanked by loxP sites, the flanked gene can be deleted in a tissue specific manner. To target selective expression in megakaryocytes we used the promoter region of platelet factor-4 (PF4). The DNA transgenic construct consisted of the 387-bp of the promoter region of human PF4 (nucleotides −312 to +75) followed by the cDNA of Cre cloned at the start codon of the native gene, and the polyA sequence of the human β-globin gene. Transgenic animals were generated using routine pronuclear injection of fertilized oocytes. Transgenic mice were genotyped by a combination of Southern blot analysis and PCR. To evaluate functionality and tissue specificity of Cre expression, hPF4-Cre transgenic mice were crossed with ROSA26-lacZ reporter mice (B6.129S4-Gt(ROSA)26Sortm1Sor). In this reporter the cDNA for lacZ has been introduced into the Rosa26 locus preceded by an intervening sequence flanked by two loxP sites. In cells expressing Cre, recombination at the two loxP sites produces excision of the intervening sequence allowing the expression lacZ, thus β-galactosidase activity is a surrogate for Cre activity. β-galactosidase activity was analyzed by X-gal assay in megakaryocytes of bone marrow harvested from animals harboring the Cre transgene and reporter gene. We used the littermates that were either ROSA26-lacZ reporter/WT or WT/hPF4- Cre as negative controls, and Tg-ROSA26 (B6;129S-Gt(ROSA)26Sor), a strain that expresses lacZ in all tissues, as positive control. We have documented β-galactosidase activity that is present only in megakaryocytes and platelets in 6 established transgenic lines. In conclusion, we have generated megakaryocyte specific Cre mice using the promoter region of human platelet factor 4 (hPF4). Crossing this mouse with a loxP mouse will result in deletion of the loxP-flanked gene. This deletion will happen only in megakaryocytes. This tissue specific transgenic line is a powerful research tool for gene targeting experiments in platelets.
Figure Figure
Thrombin Regulates the Camp Level in Human Platelets through Phosphorylation /Activation of Akt.
Authors: Zhang Wei , Nale Gary , Colman Robert W. 
Published: October 2019

Abstract
Phosphorylation /activation of Akt is a critical event in platelet activation stimulated by thrombin. We previous demonstrated that the activation of PDE3A was increased concomitantly with the phosphorylation /activation of Akt. In order to demonstrate a link between these two events, in this study, we monitored thrombin-induced cAMP changes in washed platelets. We confirmed that the platelet cAMP level decreased following thrombin stimulation. The thrombin-induced decrease of cAMP was inhibited by an Akt specific inhibitor (1l-6-hydroxymethyl-chiro-inositol 2-(R)-2-O-methyl-3-O-octadecylcarbonate). This Akt inhibitor exhibited a concentration-dependent inhibition of thrombin-induced decrease of cAMP. The Akt inhibitor blocked 70 % of thrombin-induced decrease of cAMP. Moreover, a phosphoinositide 3-kinase inhibitor wortmannin also reduced the thrombin effect, consistent with its upstream position relative to Akt. These results suggested that phosphorylation /activation of Akt is required for decrease of cAMP in platelets. In addition, we found that thrombin-induced cAMP level changes were markedly reduced following preincubation of platelets with milrinone, a selective PDE3A inhibitor. We therefore examined PDE3A activity after stimulation of platelets with thrombin with or without the Akt inhibitor or wortmannin. Either the Akt inhibitor or wortmannin inhibited the thrombin-induced activation of PDE3A. Our data indicated that phosphorylation/activation of Akt plays a major role in regulation of cAMP by thrombin. The activation of Akt by thrombin results in activation of PDE3A and a consequent decrease of the intracellular cAMP level, which serves as a positive feedback enhancing the thrombin activation of platelet function. Understanding the mechanisms that are involved in regulation of PDE3A in platelets could provide new targets for therapeutic advances in the treatment of thrombotic disorders.
Thrombin Mediated Tyrosine Phosphorylation of PKCδ in Human Platelets Occurs in a Calcium- and Src Family Tyrosine Kinase- Dependent Manner.
Authors: Murugappan Swaminathan , Shankar Haripriya , Kunapuli Satya 
Published: October 2019

Abstract
Protein kinase C (PKC)-δ is a novel PKC that has been shown to be tyrosine phosphorylated upon stimulation with agonists in platelets. Tyrosine phosphorylation of PKCδ has been shown to occur in a Fyn-dependent manner downstream of glycoprotein VI (GPVI) signaling in platelets. Although thrombin causes tyrosine phosphorylation of PKCδ in platelets, the mechanism of this event is not elucidated. In this study, we investigated whether G-protein signaling pathways utilize similar pathways as GPVI in tyrosine phosphorylation of PKCδ. Protease activated receptor (PAR) -1 selective peptide, SFLLRN and PAR - 4 selective peptide, AYPGKF caused a time- and concentration-dependent increase in tyrosine phosphorylation of PKCδ in human platelets. However, AYPGKF failed to cause tyrosine phosphorylation of PKCδ in Gq-deficient mouse platelets. Both U73122, a phospholipase C (PLC) inhibitor, and dimethyl-BAPTA, an intracellular calcium chelator, inhibited the tyrosine phosphorylation of PKCδ downstream of the PAR activation suggesting a role for Gq/PLC pathways and intracellular calcium in mediating this event. Inhibition of PKC isoforms using GF109203X potentiated the tyrosine phosphorylation of PKCδ. The Src family tyrosine kinase inhibitors, PP1 and PP2 inhibited the tyrosine phosphorylation of PKCδ suggesting a role for Src family tyrosine kinase members in this event. We also found that both Lyn and Src are physically associated with PKCδ in a constitutive manner in platelets. Finally we found that there was a time-dependent activation of Src following activation of platelets with thrombin. Thus, the precomplexed Src and Lyn tyrosine kinases get activated following PAR stimulation resulting in the tyrosine phosphorylation of PKCδ. All these data indicate that tyrosine phosphorylation of PKCδ downstream of thrombin occurs in a calcium- and Src-family kinase dependent manner in human platelets.
FOG-1 Directly Binds to a Chromatin Remodeling and Deacetylase-Containing Complex To Mediate Transcriptional Repression by GATA-1.
Authors: Hong Wei , Nakazawa Minako , Chen Ying-Yu , Kori Rajashree , Rakowski Carrie , Blobel Md Gerd A. 
Published: October 2019

Abstract
Terminal erythroid maturation requires coordinated activation of erythroid marker genes and repression of genes associated with the undifferentiated state. These gene expression patterns are mediated by the concerted action of the erythroid transcription factor GATA-1 and its cofactor FOG-1 that can activate or repress transcription depending on promoter context. We and others showed previously that one mechanism by which FOG-1 functions is to facilitate GATA-1 association with certain DNA target sites in vivo. Using gene complementation studies of GATA-1-ablated erythroid cells, we show that at several GATA-1-repressed target genes (c-kit, c-myc and GATA-2) FOG-1 is dispensable for GATA-1 occupancy in vivo but essential for gene repression and histone deacetylation. To examine how FOG-1 functions as co-repressor we performed affinity chromatography, conventional protein purification and in vitro binding studies to identify proteins that bind FOG-1. We discovered that FOG-1 directly associates with the nucleosome remodeling and histone deacetylase complex NURD. This interaction is mediated by a small conserved domain at the N-terminus of FOG-1 and the MTA-1 subunit of NURD. Association of FOG-1 with NURD occurs in vivo and depends on an intact N-terminus of FOG-1. A series of point mutations across the N-terminus of FOG-1 revealed a tight correlation between NURD binding and transcriptional repression. In particular, a single point mutation at the N-terminus of FOG-1 that abrogated NURD binding also blocked gene repression by FOG-1. Finally, the ability of GATA-1 to repress transcription was impaired in erythroid cells expressing a mutant form of FOG-1 that is defective for NURD binding. Together, these studies show that FOG-1 and very likely other FOG proteins are bona fide co-repressors that link GATA proteins to histone deacetylation and nucleosome remodeling via a novel protein interaction module.
Protective Effects of No-Albumin and Albumin on Lung Injury Induced by Hypoxia/Reoxygenation in a Mouse Model of Sickle Cell Disease.
Authors: De Franceschi Lucia , Malpeli Giorgio , Janin Anne , Muchitsch Eva , Scarpa Aldo , Leboulch Philippe , Leboeuf Christhope , Beuzard Yves , Brugnara Carlo 
Published: October 2019

Abstract
Clinical manifestations of sickle cell disease are related to vaso-occlusive (VOC) events, which are responsible for acute and chronic organ damages. We have recently shown the beneficial effects of inhaled nitric oxide (NO) in both transgenic sickle cell (SAD) mice exposed to hypoxia/reoxygenation (H/R) and in sickle cell children with acute painful crisis (Blood102: 1097, 2003; JAMA289: 1136,2003). Polynitroxyl-albumine (PNA), nitrosylated at position 34, may represent a new therapeutic tool in acute sickle cell VOCs. In SAD mice, PNA was intraperitoneally (ip) administrated and a dose-response curve was determined. Methemoglobin (MetHb) levels and blood pressure were measured under normoxia. PNA, 300 mg/Kg twice a day (equal to 4.5 mM/Kg twice a d.), induced a significant but transitory decrease in blood pressure 60 min after ip injection, while MetHb levels did not change. The effects of PNA and human serum albumine (hsAlb) on ischemia/reperfusion (H/R) lung injury related to sickle cell disease were then studied. SAD mice were divided into 4 groups of 6 animals each: one served as normoxia untreated control. The other groups were exposed to 46 hrs hypoxia (8% O2) followed by 2 hrs normoxia: one served as untreated hypoxic group, one was treated with hsAlb (300 mg/Kg twice a day) and one with PNA (300 mg/Kg twice a day). We evaluated lung histopathology, complete blood counts, bronchoalveolar (BAL) fluid neutrophil counts, cytokine levels, which are activated by H/R stimulus and are modulated by inhaled NO (Blood102:1087, 2003).
In addition to histological lung damage, H/R induced an increase in blood neutrophils, a market increase in BAL total leukocyte and neutrophil counts, an increase in BAL IL-6 and IL-1β, with no significant changes in BAL IL-10 and TNF-α levels. PNA prevented the H/R lung injury, determined a reduction in H/R mediated increase in blood neutrophils, prevented the increase in BAL total leukocyte and neutrophil counts and in BAL IL-6 and IL-1β levels, while no change was observed in BAL IL-10, TNF-α and MetHb levels. hsAlb ameliorates the H/R lung injury but it did not affect either the H/R induced blood neutrophils, and BAL cells and cytokines. These results show that the beneficial effects of PNA are similar to those observed with inhaled NO and that PNA could be therapeutically efficacious in sickle cell disease.