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Sample records for heparin binding epidermal

  1. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

    Science.gov (United States)

    Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C

    2017-05-01

    High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.

  2. Overexpression of Heparin-Binding Epidermal Growth Factor-Like Growth Factor Mediates Liver Fibrosis in Transgenic Mice.

    Science.gov (United States)

    Guo, Yongze; Ding, Qian; Chen, Lei; Ji, Chenguang; Hao, Huiyao; Wang, Jia; Qi, Wei; Xie, Xiaoli; Ma, Junji; Li, Aidi; Jiang, Xiaoyu; Li, Xiaotian; Jiang, Huiqing

    2017-08-01

    The role of heparin-binding epidermal growth factor-like growth factor (HB-EGF) in liver fibrosis is not clear and is sometimes even contradictory. To clarify this role, a HB-EGF transgenic (Tg) mouse model was, for the first time, used to evaluate the functions of HB-EGF in liver fibrosis. For the in vivo study, carbon tetrachloride injection and bile duct ligation treatment were used to induce liver fibrosis in HB-EGF Tg mice and wild-type (WT) mice, respectively. Primary hepatic satellite cells (HSCs) were isolated from HB-EGF Tg and WT mice for the in vitro study. Compared with the WT mice, HB-EGF Tg mice were shown to develop more severe liver fibrosis when treated with carbon tetrachloride or bile duct ligation, with increased matrix metalloproteinases 13 activity and enhanced expression of fibrogenic genes including α-smooth muscle actin and collagen I. HB-EGF gene transfer led to an increase in proliferation and a decrease in apoptosis in primary HSCs. The ERK signaling pathway was more highly activated in primary HSCs from HB-EGF Tg mice than in those from WT mice. Our investigation confirmed the profibrotic effect of HB-EGF on the liver using a Tg mouse model. This result may contribute to the elucidation of HB-EGF as a therapeutic target in liver fibrosis. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  3. Serum Heparin-binding Epidermal Growth Factor-like Growth Factor (HB-EGF) as a Biomarker for Primary Ovarian Cancer.

    Science.gov (United States)

    Miyata, Kohei; Yotsumoto, Fusanori; Fukagawa, Satoshi; Kiyoshima, Chihiro; Ouk, Nam Sung; Urushiyama, Daichi; Ito, Tomohiro; Katsuda, Takahiro; Kurakazu, Masamitsu; Araki, Ryota; Sanui, Ayako; Miyahara, Daisuke; Murata, Masaharu; Shirota, Kyoko; Yagi, Hiroshi; Takono, Tadao; Kato, Kiyoko; Yaegashi, Nobuo; Akazawa, Kohei; Kuroki, Masahide; Yasunaga, Shin'ichiro; Miyamoto, Shingo

    2017-07-01

    Ovarian cancer is the most lethal malignancy among gynaecological cancers. Although many anticancer agents have been developed for the treatment of ovarian cancer, it continues to have an extremely poor prognosis. Heparin-binding epidermal growth factor-like grown factor (HB-EGF) has been reported to be a rational therapeutic target for ovarian cancer. Here, we evaluated the clinical significance of serum HB-EGF by examining the association between prognosis and serum HB-EGF levels in patients with primary ovarian cancer. We found that high serum HB-EGF concentrations were significantly associated with poor prognosis in a combined cohort of patients with all stages of ovarian cancer, as well as in a subset of patients with advanced disease. In addition, serum HB-EGF levels increased as the cancer advanced. These data suggest that serum HB-EGF may be a target for the design of novel therapies for ovarian cancer. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  4. M2 macrophages induce ovarian cancer cell proliferation via a heparin binding epidermal growth factor/matrix metalloproteinase 9 intercellular feedback loop.

    Science.gov (United States)

    Carroll, Molly J; Kapur, Arvinder; Felder, Mildred; Patankar, Manish S; Kreeger, Pamela K

    2016-12-27

    In ovarian cancer, a high ratio of anti-inflammatory M2 to pro-inflammatory M1 macrophages correlates with poor patient prognosis. The mechanisms driving poor tumor outcome as a result of the presence of M2 macrophages in the tumor microenvironment remain unclear and are challenging to study with current techniques. Therefore, in this study we utilized a micro-culture device previously developed by our lab to model concentrated paracrine signaling in order to address our hypothesis that interactions between M2 macrophages and ovarian cancer cells induce tumor cell proliferation. Using the micro-culture device, we determined that co-culture with M2-differentiated primary macrophages or THP-1 increased OVCA433 proliferation by 10-12%. This effect was eliminated with epidermal growth factor receptor (EGFR) or heparin-bound epidermal growth factor (HB-EGF) neutralizing antibodies and HBEGF expression in peripheral blood mononuclear cells from ovarian cancer patients was 9-fold higher than healthy individuals, suggesting a role for HB-EGF in tumor progression. However, addition of HB-EGF at levels secreted by macrophages or macrophage-conditioned media did not induce proliferation to the same extent, indicating a role for other factors in this process. Matrix metalloproteinase-9, MMP-9, which cleaves membrane-bound HB-EGF, was elevated in co-culture and its inhibition decreased proliferation. Utilizing inhibitors and siRNA against MMP9 in each population, we determined that macrophage-secreted MMP-9 released HB-EGF from macrophages, which increased MMP9 in OVCA433, resulting in a positive feedback loop to drive HB-EGF release and increase proliferation in co-culture. Identification of multi-cellular interactions such as this may provide insight into how to most effectively control ovarian cancer progression.

  5. The cell-penetrating peptide domain from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) has anti-inflammatory activity in vitro and in vivo

    International Nuclear Information System (INIS)

    Lee, Jue-Yeon; Seo, Yoo-Na; Park, Hyun-Jung; Park, Yoon-Jeong; Chung, Chong-Pyoung

    2012-01-01

    Highlights: ► HBP sequence identified from HB-EGF has cell penetration activity. ► HBP inhibits the NF-κB dependent inflammatory responses. ► HBP directly blocks phosphorylation and degradation of IκBα. ► HBP inhibits nuclear translocation of NF-κB p65 subunit. -- Abstract: A heparin-binding peptide (HBP) sequence from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) was identified and was shown to exhibit cell penetration activity. This cell penetration induced an anti-inflammatory reaction in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. HBP penetrated the cell membrane during the 10 min treatment and reduced the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cytokines (TNF-α and IL-6) in a concentration-dependent manner. Additionally, HBP inhibited the LPS-induced upregulation of cytokines, including TNF-α and IL-6, and decreased the interstitial infiltration of polymorphonuclear leukocytes in a lung inflammation model. HBP inhibited NF-κB-dependent inflammatory responses by directly blocking the phosphorylation and degradation of IκBα and by subsequently inhibiting the nuclear translocation of the p65 subunit of NF-κB. Taken together, this novel HBP may be potentially useful candidate for anti-inflammatory treatments and can be combined with other drugs of interest to transport attached molecules into cells.

  6. Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is increased in osteoarthritis and regulates chondrocyte catabolic and anabolic activities

    Science.gov (United States)

    Long, D.L.; Ulici, V.; Chubinskaya, S.; Loeser, R.F.

    2015-01-01

    Objective We determined if the epidermal growth factor receptor ligand HB-EGF is produced in cartilage and if it regulates chondrocyte anabolic or catabolic activity. Methods HB-EGF expression was measured by quantitative PCR using RNA isolated from mouse knee joint tissues and from normal and OA human chondrocytes. Immunohistochemistry was performed on normal and OA human cartilage and meniscus sections. Cultured chondrocytes were treated with fibronectin fragments (FN-f) as a catabolic stimulus and osteogenic protein 1 (OP-1) as an anabolic stimulus. Effects of HB-EGF on cell signaling were analyzed by immunoblotting of selected signaling proteins. MMP-13 was measured in conditioned media, proteoglycan synthesis was measured by sulfate incorporation, and matrix gene expression by quantitative PCR. Results HB-EGF expression was increased in 12-month old mice at 8 weeks after surgery to induce OA and increased amounts of HB-EGF were noted in human articular cartilage from OA knees. FN-f stimulated chondrocyte HB-EGF expression and HB-EGF stimulated chondrocyte MMP-13 production. However, HB-EGF was not required for FN-f stimulation of MMP-13 production. HB-EGF activated the ERK and p38 MAP kinases and stimulated phosphorylation of Smad1 at an inhibitory serine site which was associated with inhibition of OP-1 mediated proteoglycan synthesis and reduced aggrecan (ACAN) but not COL2A1 expression. Conclusion HB-EGF is a new factor identified in OA cartilage that promotes chondrocyte catabolic activity while inhibiting anabolic activity suggesting it could contribute to the catabolic-anabolic imbalance seen in OA cartilage. PMID:25937027

  7. Structural and binding studies of SAP-1 protein with heparin.

    Science.gov (United States)

    Yadav, Vikash K; Mandal, Rahul S; Puniya, Bhanwar L; Kumar, Rahul; Dey, Sharmistha; Singh, Sarman; Yadav, Savita

    2015-03-01

    SAP-1 is a low molecular weight cysteine protease inhibitor (CPI) which belongs to type-2 cystatins family. SAP-1 protein purified from human seminal plasma (HuSP) has been shown to inhibit cysteine and serine proteases and exhibit interesting biological properties, including high temperature and pH stability. Heparin is a naturally occurring glycosaminoglycan (with varied chain length) which interacts with a number of proteins and regulates multiple steps in different biological processes. As an anticoagulant, heparin enhances inhibition of thrombin by the serpin antithrombin III. Therefore, we have employed surface plasmon resonance (SPR) to improve our understanding of the binding interaction between heparin and SAP-1 (protease inhibitor). SPR data suggest that SAP-1 binds to heparin with a significant affinity (KD = 158 nm). SPR solution competition studies using heparin oligosaccharides showed that the binding of SAP-1 to heparin is dependent on chain length. Large oligosaccharides show strong binding affinity for SAP-1. Further to get insight into the structural aspect of interactions between SAP-1 and heparin, we used modelled structure of the SAP-1 and docked with heparin and heparin-derived polysaccharides. The results suggest that a positively charged residue lysine plays important role in these interactions. Such information should improve our understanding of how heparin, present in the reproductive tract, regulates cystatins activity. © 2014 John Wiley & Sons A/S.

  8. Effects of heparin on insulin binding and biological activity

    International Nuclear Information System (INIS)

    Kriauciunas, K.M.; Grigorescu, F.; Kahn, C.R.

    1987-01-01

    The effect of heparin, a polyanionic glycosaminoglycan known to alter the function of many proteins, on insulin binding and bioactivity was studied. Cultured human lymphocytes (IM-9) were incubated with varying concentrations of heparin, then extensively washed, and 125 I-labeled insulin binding was measured. Heparin at concentrations used clinically for anticoagulation (1-50 U/ml) inhibited binding in a dose-dependent manner; 50% inhibition of binding occurred with 5-10 U/ml. Scatchard analysis indicated that the decrease in binding was due to a decrease in both the affinity and the apparent number of available insulin receptors. The effect occurred within 10 min at 22 degrees C and persisted even after the cells were extensively washed. Inhibition of insulin binding also occurred when cells were preincubated with heparinized plasma or heparinized serum but not when cells were incubated with normal serum or plasma from blood anticoagulated with EDTA. By contrast, other polyanions and polycations, e.g., poly-L-glutamic acid, poly-L-lysine, succinylated poly-L-lysine, and histone, did not inhibit binding. Heparin also inhibited insulin binding in Epstein-Barr (EB) virus-transformed lymphocytes but had no effect on insulin binding to isolated adipocytes, human erythrocytes, or intact hepatoma cells. When isolated adipocytes were incubated with heparin, there was a dose-dependent inhibition of insulin-stimulated glucose oxidation and, to a lesser extent, of basal glucose oxidation. Although heparin has no effect on insulin binding to intact hepatoma cells, heparin inhibited both insulin binding and insulin-stimulated autophosphorylation in receptors solubilized from these cells

  9. A sensitive competitive binding assay for exogenous and endogenous heparins

    International Nuclear Information System (INIS)

    Dawes, J.; Pepper, D.S.

    1982-01-01

    A new type of assay for heparins has been devised, in which the test material competes with 125 I-labelled heparin for binding to protamine-Sepharose. The assay is very sensitive and will measure heparin concentrations down to 10 ng ml-1. It responds to both the degree of sulphation and the molecular weight of acidic polysaccharides, but is independent of their biological activities. It can be used to quantitate heparins in biological fluids after pretreatment of the samples with protease. In this way endogenous heparins were measured in normal human serum, plasma and urine. The assay is extremely versatile and has great potential for the investigation of endogenous and exogenous heparins

  10. Heparin-associated thrombocytopenia: antibody binding specificity to platelet antigens.

    Science.gov (United States)

    Lynch, D M; Howe, S E

    1985-11-01

    Sera from four patients with heparin-associated thrombocytopenia (HAT) were evaluated by a quantitative enzyme-linked immunosorbent assay (ELISA) to detect heparin-dependent serum platelet-bindable immunoglobulin (S-PBIg) and by Western blotting and immunoprecipitation to investigate the specificity of the antibody binding. All HAT sera showed mildly increased S-PBIg (mean, 7.8 fg per platelet; normal, less than 6.0 fg per platelet) to intact target platelets in the ELISA, which was markedly increased in the presence of heparin (mean, 20.9 fg per platelet). This increase was 20-fold greater than normal control sera, which showed a mean differential increase of only 0.5 fg per platelet. Immunoglobulin binding specificity to platelet antigens was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis of platelet lysate with transfer of the platelet fractions onto nitrocellulose strips (Western blotting) and subsequent immunoassay using HAT and normal sera. In the presence of heparin, the four HAT patients demonstrated increased binding of immunoglobulin to platelet antigens of apparent molecular weights of 180, 124, and 82 kd. Radiolabeled heparin when incubated with HAT sera, normal sera, or albumin blanks bound to platelet proteins of the same apparent molecular weights. These observations are consistent with current hypotheses suggesting that HAT antibody is directed to heparin-platelet complexes or, alternatively, that heparin induces conformational change of antigenic sites on the platelet membrane.

  11. Improved assay for measuring heparin binding to bull sperm

    International Nuclear Information System (INIS)

    Miller, D.J.; Ax, R.L.

    1988-01-01

    The binding of heparin to sperm has been used to study capacitation and to rank relative fertility of bulls. Previous binding assays were laborious, used 10 7 sperm per assay point, and required large amounts of radiolabeled heparin. A modified heparin-binding assay is described that used only 5 x 10 4 cells per incubation well and required reduced amounts of [ 3 H] heparin. The assay was performed in 96-well Millititer plates, enabling easy incubation and filtering. Dissociation constants and concentrations of binding sites did not differ if analyzed by Scatchard plots, Woolf plots, or by log-logit transformed weighted nonlinear least squares regression, except in the case of outliers. In such cases, Scatchard analysis was more sensitive to outliers. Nonspecific binding was insignificant using nonlinear logistic fit regression and a proportion graph. The effects were tested of multiple free-thawing of sperm in either a commercial egg yolk extender, 40 mM Tris buffer with 8% glycerol, or 40 mM Tris buffer without glycerol. Freeze-thawing in extender did not affect the dissociation constant or the concentration of binding sites. However, freeze-thawing three times in 40 mM Tris reduced the concentration of binding sites and lowered the dissociation constant (raised the affinity). The inclusion of glycerol in the 40 mM Tris did not significantly affect the estimated dissociation constant or the concentration of binding sites as compared to 40 mM Tris without glycerol

  12. Proteomic analysis of heparin-binding proteins from human seminal ...

    Indian Academy of Sciences (India)

    Prakash

    (MALDI TOF/MS) for protein analysis of human HBPs. We resolved 70 ... Thus, the combined effects of seminal plasma components support the survival of ...... The BBXB motif of RANTES is the principal site for heparin binding and controls ...

  13. Dansyl (5-dimethylaminonaphthalene-1-sulphonyl)-heparin binds antithrombin III and platelet factor 4 at separate sites

    Science.gov (United States)

    Piepkorn, Michael W.

    1981-01-01

    Antithrombin III binds to, and thereby augments the fluorescence of, dansyl-(5-dimethylaminonaphthalene-1-sulphonyl)-heparin; platelet factor 4 binding to the fluorescent heparin has little of this effect. Competition studies in which antithrombin III competes with platelet factor 4 for heparin binding demonstrate that heparin can simultaneously bind both proteins. PMID:7317004

  14. In vivo studies on the binding of heparin and its fractions with platelet factor 4

    International Nuclear Information System (INIS)

    Walz, D.A.; Hung, G.L.

    1985-01-01

    PF4 has a half-life in plasma of less than 3 minutes, and its rapid clearance appears to be a function of binding to the vascular endothelium. Once bound to the endothelium, PF4 can be released by heparin in a time-dependent manner; recovery is greater the sooner heparin is administered following PF4 infusion. This heparin-induced release of PF4 can be abolished if the heparin is first complexed with hexadimethrine bromide. Likewise, this heparin-induced release of PF4 is dependent upon the type of heparin used; low molecular weight heparin fractions and fragments do not cause the PF4 rebound seen with intact heparin. Thus, it would appear that low molecular weight forms of heparin are advantageous in that their in vivo administration would not be mediated by such platelet modulators as PF4

  15. Removal of glycosaminoglycans from bovine granulosa cells contributes to increased binding of hydrogen-3 heparin

    Energy Technology Data Exchange (ETDEWEB)

    Ax, R.L.; Stodd, C.M.; Boehm, S.K.; Bellin, M.E.

    1986-02-01

    Granulosa cells from small or large bovine follicles were pretreated with enzymes that hydrolyze various glycosaminoglycans, and binding of (/sup 3/H)-heparin to the granulosa was measured. Binding of (/sup 3/H) heparin increased significantly after enzymatic pretreatments with chondroitinase ABC and fungal hyaluronidase, and similar results were obtained with granulosa from small and large follicles. No changes in binding of (/sup 3/H) heparin were detected after hydrolyses with chondroitinase AC and heparinase in either follicle size. Heparitinase, which hydrolyzes heparan sulfate, led to a significant 50% increase in binding of (/sup 3/H) heparin to granulosa from large follicles but was without effect in small follicles. These results suggest that the lower binding of (/sup 3/H) heparin, which has been reported with follicular enlargement, may be due to heparan sulfate occupying or obstructing binding sites for heparin on granulosa from large follicles.

  16. Layer-by-Layer Heparinization of the Cell Surface by Using Heparin-Binding Peptide Functionalized Human Serum Albumin.

    Science.gov (United States)

    Song, Guowei; Hu, Yaning; Liu, Yusheng; Jiang, Rui

    2018-05-20

    Layer-by-layer heparinization of therapeutic cells prior to transplantation is an effective way to inhibit the instant blood-mediated inflammatory reactions (IBMIRs), which are the major cause of early cell graft loss during post-transplantation. Here, a conjugate of heparin-binding peptide (HBP) and human serum albumin (HSA), HBP-HSA, was synthesized by using heterobifunctional crosslinker. After the first heparin layer was coated on human umbilical vein endothelial cells (HUVECs) by means of the HBP-polyethylene glycol-phospholipid conjugate, HBP-HSA and heparin were then applied to the cell surface sequentially to form multiple layers. The immobilization and retention of heparin were analyzed by confocal microscopy and flow cytometry, respectively, and the cytotoxity of HBP-HSA was further evaluated by cell viability assay. Results indicated that heparin was successfully introduced to the cell surface in a layer-by-layer way and retained for at least 24 h, while the cytotoxity of HBP-HSA was negligible at the working concentration. Accordingly, this conjugate provides a promising method for co-immobilization of heparin and HSA to the cell surface under physiological conditions with improved biocompatibility.

  17. Relationship of nonreturn rates of dairy bulls to binding affinity of heparin to sperm

    International Nuclear Information System (INIS)

    Marks, J.L.; Ax, R.L.

    1985-01-01

    The binding of the glycosaminoglycan [ 3 H] heparin to bull spermatozoa was compared with nonreturn rates of dairy bulls. Semen samples from five bulls above and five below an average 71% nonreturn rate were used. Samples consisted of first and second ejaculates on a single day collected 1 d/wk for up to 5 consecutive wk. Saturation binding assays using [ 3 H] heparin were performed to quantitate the binding characteristics of each sample. Scatchard plot analyses indicated a significant difference in the binding affinity for [ 3 H] heparin between bulls of high and low fertility. Dissociation constants were 69.0 and 119.3 pmol for bulls of high and low fertility, respectively. In contrast, the number of binding sites for [ 3 H] heparin did not differ significantly among bulls. Differences in binding affinity of [ 3 H] heparin to bull sperm might be used to predict relative fertility of dairy bulls

  18. A Heparin Binding Motif Rich in Arginine and Lysine is the Functional Domain of YKL-40

    Directory of Open Access Journals (Sweden)

    Nipaporn Ngernyuang

    2018-02-01

    Full Text Available The heparin-binding glycoprotein YKL-40 (CHI3L1 is intimately associated with microvascularization in multiple human diseases including cancer and inflammation. However, the heparin-binding domain(s pertinent to the angiogenic activity have yet been identified. YKL-40 harbors a consensus heparin-binding motif that consists of positively charged arginine (R and lysine (K (RRDK; residues 144–147; but they don't bind to heparin. Intriguingly, we identified a separate KR-rich domain (residues 334–345 that does display strong heparin binding affinity. A short synthetic peptide spanning this KR-rich domain successfully competed with YKL-40 and blocked its ability to bind heparin. Three individual point mutations, where alanine (A substituted for K or R (K337A, K342A, R344A, led to remarkable decreases in heparin-binding ability and angiogenic activity. In addition, a neutralizing anti-YKL-40 antibody that targets these residues and prevents heparin binding impeded angiogenesis in vitro. MDA-MB-231 breast cancer cells engineered to express ectopic K337A, K342A or R344A mutants displayed reduced tumor development and compromised tumor vessel formation in mice relative to control cells expressing wild-type YKL-40. These data reveal that the KR-rich heparin-binding motif is the functional heparin-binding domain of YKL-40. Our findings shed light on novel molecular mechanisms underlying endothelial cell angiogenesis promoted by YKL-40 in a variety of diseases.

  19. Enhancement of trophoblast differentiation and survival by low molecular weight heparin requires heparin-binding EGF-like growth factor.

    Science.gov (United States)

    Bolnick, Alan D; Bolnick, Jay M; Kohan-Ghadr, Hamid-Reza; Kilburn, Brian A; Pasalodos, Omar J; Singhal, Pankaj K; Dai, Jing; Diamond, Michael P; Armant, D Randall; Drewlo, Sascha

    2017-06-01

    Does low molecular weight heparin (LMWH) require heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF) signaling to induce extravillous trophoblast differentiation and decrease apoptosis during oxidative stress? LMWH increased HBEGF expression and secretion, and HBEGF signaling was required to stimulate trophoblast extravillous differentiation, increase invasion in vitro and reduce trophoblast apoptosis during oxidative stress. Abnormal trophoblast differentiation and survival contribute to placental insufficiency syndromes, including preeclampsia and intrauterine growth restriction. Preeclampsia often manifests as a pro-thrombotic state, with unsuccessful transformation of the spiral arteries that reduces oxygen supply and can produce placental infarction. LMWH improves placental function by increasing blood flow. Recent data suggest that the actions of LMWH transcend its anti-coagulative properties, but the molecular mechanism is unknown. There is evidence that LMWH alters the expression of human HBEGF in trophoblast cells, which regulates human trophoblast pathophysiology. HBEGF, itself, is capable of increasing trophoblast survival and invasiveness. First-trimester placental explants and the HTR-8/SVneo cell line, established using extravillous trophoblast outgrowths from first-trimester villous explants, were treated in vitro with LMWH to examine the effects on HBEGF signaling and trophoblast function under normal physiological and pathological conditions. A highly specific antagonist of HBEGF and other inhibitors of HBEGF downstream signaling were used to determine the relationship between LMWH treatment and HBEGF. Placental tissues (n = 5) were obtained with IRB approval and patient consent from first-trimester terminations. Placental explants and HTR-8/SVneo cells were cultured on plastic or Matrigel™ and treated with a therapeutic dose of LMWH (Enoxaparin; 10 IU/ml), with or without CRM197, pan Erb-B2 Receptor Tyrosine Kinase (ERBB

  20. Endostatin competes with bFGF for binding to heparin-like glycosaminoglycans

    International Nuclear Information System (INIS)

    Reis, Renata C.M.; Schuppan, Detlef; Barreto, Aline C.; Bauer, Michael; Bork, Jens P.; Hassler, Gerda; Coelho-Sampaio, Tatiana

    2005-01-01

    Endostatin is a potent inhibitor of angiogenesis and tumor growth. Here, we used human endothelial cells from lung capillaries to investigate if endostatin competes with the proangiogenic growth factors, bFGF and VEGF, for binding to costimulatory heparan sulfate molecules. Endostatin inhibited 79% and 95% of the increase in proliferation induced by bFGF and VEGF 165 , respectively. The stimulatory effect of VEGF 165 was not affected by the presence of exogenous heparin, while that of bFGF was further enhanced in the presence of up to 0.1 μg/ml heparin. The heparin-binding protein protamine completely blocked bFGF-stimulated proliferation, while it did not affect the response to VEGF 165 . Simultaneous addition of endostatin and protamine led to additive effects both in inhibition of proliferation and induction of apoptosis. Although bFGF was found to bind more strongly to heparin-Sepharose than endostatin, the latter, but not the former, displaced protamine from heparin in solution, which supports the notion that endostatin can compete with bFGF for binding to heparan sulfate in vivo. Taken as a whole, our results demonstrate that there is a direct connection between the dependence of endostatin activity on heparin-like glycosaminoglycans and its ability to antagonize bFGF

  1. Heparin binding domain of antithrombin III: Characterization using a synthetic peptide directed polyclonal antibody

    International Nuclear Information System (INIS)

    Smith, J.W.; Dey, B.; Knauer, D.J.

    1990-01-01

    Antithrombin III (ATIII) is a plasma-borne serine protease inhibitor that apparently forms covalent complexes with thrombin. The interaction between ATIII and thrombin is enhanced several thousandfold by the glycosaminoglycan, heparin. The authors have previously proposed that the heparin binding site of ATIII residues within a region extending from amino acid residues 114-156. Computer-assisted analysis of this region revealed the presence of a 22 amino acid domain (residues 124-145), part of which shows a strong potential for the formation of an amphipathic helix: hydrophobic on one face and highly positively charged on the other. In the presence studies, polyclonal antisera were generated against a synthetic peptide corresponding to residues 124-145 in native human ATIII. Affinity-purified IgG from these antisera, as well as monovalent Fab's derived from them, specifically blocked the binding of heparin to ATIII. Additionally, occupancy of the heparin binding site by these same monovalent and bivalent IgG's at least partially substituted for heparin, accelerating linkage formation between ATIII and thrombin. These results provide the first immunological evidence that region 124-145 is directly involved in the binding of heparin to ATIII and that an antibody-induced conformational change within this region can mediate ATIII activation

  2. Detection of growth factor binding to gelatin and heparin using a photonic crystal optical biosensor

    International Nuclear Information System (INIS)

    Morgan, Abby W.; Chan, Leo L.; Sendemir-Urkmez, Aylin; Cunningham, Brian T.; Jamison, Russell D.

    2010-01-01

    Drug-carrier interactions are important to protein controlled release systems to protect the protein from denaturation and ensure properly timed release. A novel photonic crystal biosensor was used to investigate a gelatin-protein controlled release system to determine the amount of protein bound to the carrier at physiological conditions. The Biomolecular Interaction Detection (BIND) system reflects a narrow band of wavelengths when white light is shone incident to the grating. As mass is deposited onto the surface, the peak wavelength value is shifted due to changes in the optical density of the biosensor. The BIND system was used to detect the binding of growth factors onto acidic gelatin, basic gelatin, and heparin on the sensor surface. Through a series of experiments, including functionalizing the sensor, adjusting the ionic strength of the solution, adjusting the substrate concentration, and minimizing non-specific signal, the adsorption of the gelatins and heparin on the sensor was enhanced. The binding interaction of recombinant human transforming growth factor (rhTGF)-β1 and bone morphogenetic protein (rhBMP)-2 with the two types of gelatin and heparin were investigated. The strength of the interaction between rhTGF-β1 and the substrates is in the following order: heparin > acidic gelatin > basic gelatin. RhBMP-2 bound to the substrates but with less intensity than TGF-β1: heparin > basic gelatin > acidic gelatin. This work provides support for the controlled release mechanism through degradation of the gelatin carrier.

  3. Heparin-independent, PF4-dependent binding of HIT antibodies to platelets: implications for HIT pathogenesis.

    Science.gov (United States)

    Padmanabhan, Anand; Jones, Curtis G; Bougie, Daniel W; Curtis, Brian R; McFarland, Janice G; Wang, Demin; Aster, Richard H

    2015-01-01

    Antibodies specific for platelet factor 4 (PF4)/heparin complexes are the hallmark of heparin-induced thrombocytopenia and thrombosis (HIT), but many antibody-positive patients have normal platelet counts. The basis for this is not fully understood, but it is believed that antibodies testing positive in the serotonin release assay (SRA) are the most likely to cause disease. We addressed this issue by characterizing PF4-dependent binding of HIT antibodies to intact platelets and found that most antibodies testing positive in the SRA, but none of those testing negative, bind to and activate platelets when PF4 is present without any requirement for heparin (P HIT antibodies recognize PF4 in a complex with heparin, only a subset of these antibodies recognize more subtle epitopes induced in PF4 when it binds to CS, the major platelet glycosaminoglycan. Antibodies having this property could explain "delayed HIT" seen in some individuals after discontinuation of heparin and the high risk for thrombosis that persists for weeks in patients recovered from HIT. © 2015 by The American Society of Hematology.

  4. Furin proteolytically processes the heparin-binding region of extracellular superoxide dismutase

    DEFF Research Database (Denmark)

    Bowler, Russell P; Nicks, Mike; Olsen, Dorte Aa

    2002-01-01

    Extracellular superoxide dismutase (EC-SOD) is an antioxidant enzyme that attenuates brain and lung injury from oxidative stress. A polybasic region in the carboxyl terminus distinguishes EC-SOD from other superoxide dismutases and determines EC-SOD's tissue half-life and affinity for heparin....... There are two types of EC-SOD that differ based on the presence or absence of this heparin-binding region. It has recently been shown that proteolytic removal of the heparin-binding region is an intracellular event (Enghild, J. J., Thogersen, I. B., Oury, T. D., Valnickova, Z., Hojrup, P., and Crapo, J. D...... of intracellular proteases implicate furin as a processing protease. In vitro experiments using furin and purified EC-SOD suggest that furin proteolytically cleaves EC-SOD in the middle of the polybasic region and then requires an additional carboxypeptidase to remove the remaining lysines and arginines...

  5. Acyl-CoA binding protein and epidermal barrier function

    DEFF Research Database (Denmark)

    Bloksgaard, Maria; Neess, Ditte; Færgeman, Nils J

    2014-01-01

    The acyl-CoA binding protein (ACBP) is a 10kDa intracellular protein expressed in all eukaryotic species and mammalian tissues investigated. It binds acyl-CoA esters with high specificity and affinity and is thought to act as an intracellular transporter of acyl-CoA esters between different...... includes tousled and greasy fur, development of alopecia and scaling of the skin with age. Furthermore, epidermal barrier function is compromised causing a ~50% increase in transepidermal water loss relative to that of wild type mice. Lipidomic analyses indicate that this is due to significantly reduced...

  6. Simple and Efficient Purification of Recombinant Proteins Using the Heparin-Binding Affinity Tag.

    Science.gov (United States)

    Jayanthi, Srinivas; Gundampati, Ravi Kumar; Kumar, Thallapuranam Krishnaswamy Suresh

    2017-11-01

    Heparin, a member of the glycosaminoglycan family, is known to interact with more than 400 different types of proteins. For the past few decades, significant progress has been made to understand the molecular details involved in heparin-protein interactions. Based on the structural knowledge available from the FGF1-heparin interaction studies, we have designed a novel heparin-binding peptide (HBP) affinity tag that can be used for the simple, efficient, and cost-effective purification of recombinant proteins of interest. HBP-tagged fusion proteins can be purified by heparin Sepharose affinity chromatography using a simple sodium chloride gradient to elute the bound fusion protein. In addition, owing to the high density of positive charges on the HBP tag, recombinant target proteins are preferably expressed in their soluble forms. The purification of HBP-fusion proteins can also be achieved in the presence of chemical denaturants, including urea. Additionally, polyclonal antibodies raised against the affinity tag can be used to detect HBP-fused target proteins with high sensitivity. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  7. Heparin binding sites on Ross River virus revealed by electron cryo-microscopy

    International Nuclear Information System (INIS)

    Zhang Wei; Heil, Marintha; Kuhn, Richard J.; Baker, Timothy S.

    2005-01-01

    Cell surface glycosaminoglycans play important roles in cell adhesion and viral entry. Laboratory strains of two alphaviruses, Sindbis and Semliki Forest virus, have been shown to utilize heparan sulfate as an attachment receptor, whereas Ross River virus (RRV) does not significantly interact with it. However, a single amino acid substitution at residue 218 in the RRV E2 glycoprotein adapts the virus to heparan sulfate binding and expands the host range of the virus into chicken embryo fibroblasts. Structures of the RRV mutant, E2 N218R, and its complex with heparin were determined through the use of electron cryo-microscopy and image reconstruction methods. Heparin was found to bind at the distal end of the RRV spikes, in a region of the E2 glycoprotein that has been previously implicated in cell-receptor recognition and antibody binding

  8. Thermodynamic parameters associated with the binding of adrenaline and norephedrine to heparin

    International Nuclear Information System (INIS)

    Ali-Ali, A.K.; Buchanan, J.D.; Power, D.M.; Butler, J.

    1983-01-01

    Pulse radiolysis was used to determine the thermodynamic parameters (ΔG', ΔH' and ΔS') governing the binding of adrenalin and norephedrine to heparin. The complexes were completely dissociated by increasing concentrations of inorganic salts. Lower concentrations of divalent cations (e.g. Ca 2+ ) were more necessary to affect dissociation than those of monovalent cations (e.g. Na + ). For each interaction, an increase in drug binding occurred as the temperature was increased from ambient. However, a transition temperature was observed (48 degC) above which the drug was progressively released as temperature was increased. These observations probably reflect conformational changes induced in the heparin below and above its melting temperature. (author)

  9. Aggregated forms of bull seminal plasma proteins and their heparin-binding activity

    Czech Academy of Sciences Publication Activity Database

    Jelínková, Petra; Ryšlavá, H.; Liberda, J.; Jonáková, Věra; Tichá, M.

    2004-01-01

    Roč. 69, - (2004), s. 616-630 ISSN 0010-0765 R&D Projects: GA ČR GA303/02/0433; GA ČR GP303/02/P069; GA MZd NJ7463 Institutional research plan: CEZ:AV0Z5052915; CEZ:MSM 113100001 Keywords : bull seminal plasma proteins * heparin-binding proteins * aggregated forms of proteins Subject RIV: CE - Biochemistry Impact factor: 1.062, year: 2004

  10. Heparin-binding peptide amphiphile supramolecular architectures as platforms for angiogenesis and drug delivery

    Science.gov (United States)

    Chow, Lesleyann W.

    A fascinating phenomenon in nature is the self-assembly of molecules into a functional, hierarchical structure. In the past decade, the Stupp Laboratory has developed several classes of self-assembling biomaterials, one of which is the synthetic peptide amphiphile (PA). Self-assembling PAs are attractive and versatile biomolecules that can be customized for specific applications in regenerative medicine. In particular, a heparin-binding peptide amphiphile (HBPA) containing a specific heparin-binding peptide sequence was used here to induce angiogenesis and serve as a delivery vehicle for growth factors and small hydrophobic molecules. Throughout this dissertation, the HBPA/heparin system is used in different architectures for a variety of regenerative medicine applications. In one aspect of this work, hybrid scaffolds made from HBPA/heparin gelled on a poly(L-lactic acid) (PLLA) fiber mesh were used to promote angiogenesis to facilitate pancreatic islet transplantation for the treatment of type 1 diabetes. Delivery of growth factors with HBPA/PLLA scafflolds increased vessel density in vivo and correlated with improved transplant outcomes in a streptozotocin-induced diabetic mouse model. Soluble HBPA nanofiber architectures were also useful for islet transplantation applications. These nanofibers were used at concentrations below gelation to deliver growth factors into the dense islet cell aggregate, promoting cell survival and angiogenesis in vitro. The nanostructures infiltrated the islets and promoted the retention of heparin and growth factors within the islet. Another interesting growth factor release system discussed here is the HBPA membrane structure. HBPA was found to self-assemble with hyaluronic acid, a large biopolymer found in the body, into macroscopic, hierarchically-ordered membranes. Heparin was incorporated into these membranes and affected the membrane's mechanical properties and growth factor release. Human mesenchymal stem cells were also shown

  11. Basic fibroblast growth factor binds to subendothelial extracellular matrix and is released by heparitinase and heparin-like molecules

    International Nuclear Information System (INIS)

    Bashkin, P.; Doctrow, S.; Klagsbrun, M.; Svahn, C.M.; Folkman, J.; Vlodavsky, I.

    1989-01-01

    Basic fibroblast growth factor (bFGF) exhibits specific binding to the extracellular matrix (ECM) produced by cultured endothelial cells. Binding was saturable as a function both of time and of concentration of 125 I-bFGF. Scatchard analysis of FGF binding revealed the presence of about 1.5 x 10 12 binding sites/mm 2 ECM with an apparent k D of 610 nM. FGF binds to heparan sulfate (HS) in ECM as evidenced by (i) inhibition of binding in the presence of heparin or HS at 0.1-1 μg/mL, but not by chondroitin sulfate, keratan sulfate, or hyaluronic acid at 10 μg/mL, (ii) lack of binding to ECM pretreated with heparitinase, but not with chondroitinase ABC, and (iii) rapid release of up to 90% of ECM-bound FGF by exposure to heparin, HS, or heparitinase, but not to chondroitin sulfate, keratan sulfate, hyaluronic acid, or chondroitinase ABC. Oligosaccharides derived from depolymerized heparin, and as small as the tetrasaccharide, released the ECM-bound FGF, but there was little or no release of FGF by modified nonanticoagulant heparins such as totally desulfated heparin, N-desulfated heparin, and N-acetylated heparin. FGF released from ECM was biologically active, as indicated by its stimulation of cell proliferation and DNA synthesis in vascular endothelial cells and 3T3 fibroblasts. Similar results were obtained in studies on release of endogenous FGF-like mitogenic activity from Descement's membranes of bovine corneas. It is suggested that ECM storage and release of bFGF provide a novel mechanism for regulation of capillary blood vessel growth. Whereas ECM-bound FGF may be prevented from acting on endothelial cells, its displacement by heparin-like molecules and/or HS-degrading enzymes may elicit a neovascular response

  12. Human IGF-I propeptide A promotes articular chondrocyte biosynthesis and employs glycosylation-dependent heparin binding.

    Science.gov (United States)

    Shi, Shuiliang; Kelly, Brian J; Wang, Congrong; Klingler, Ken; Chan, Albert; Eckert, George J; Trippel, Stephen B

    2018-03-01

    Insulin-like growth factor I (IGF-I) is a key regulator of chondrogenesis, but its therapeutic application to articular cartilage damage is limited by rapid elimination from the repair site. The human IGF-I gene gives rise to three IGF-I propeptides (proIGF-IA, proIGF-IB and proIGF-IC) that are cleaved to create mature IGF-I. In this study, we elucidate the processing of IGF-I precursors by articular chondrocytes, and test the hypotheses that proIGF-I isoforms bind to heparin and regulate articular chondrocyte biosynthesis. Human IGF-I propeptides and mutants were overexpressed in bovine articular chondrocytes. IGF-I products were characterized by ELISA, western blot and FPLC using a heparin column. The biosynthetic activity of IGF-I products on articular chondrocytes was assayed for DNA and glycosaminoglycan that the cells produced. Secreted IGF-I propeptides stimulated articular chondrocyte biosynthetic activity to the same degree as mature IGF-I. Of the three IGF-I propeptides, only one, proIGF-IA, strongly bound to heparin. Interestingly, heparin binding of proIGF-IA depended on N-glycosylation at Asn92 in the EA peptide. To our knowledge, this is the first demonstration that N-glycosylation determines the binding of a heparin-binding protein to heparin. The biosynthetic and heparin binding abilities of proIGF-IA, coupled with its generation of IGF-I, suggest that proIGF-IA may have therapeutic value for articular cartilage repair. These data identify human pro-insulin-like growth factor IA as a bifunctional protein. Its combined ability to bind heparin and augment chondrocyte biosynthesis makes it a promising therapeutic agent for cartilage damage due to trauma and osteoarthritis. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Endothelial cell capture of heparin-binding growth factors under flow.

    Directory of Open Access Journals (Sweden)

    Bing Zhao

    2010-10-01

    Full Text Available Circulation is an important delivery method for both natural and synthetic molecules, but microenvironment interactions, regulated by endothelial cells and critical to the molecule's fate, are difficult to interpret using traditional approaches. In this work, we analyzed and predicted growth factor capture under flow using computer modeling and a three-dimensional experimental approach that includes pertinent circulation characteristics such as pulsatile flow, competing binding interactions, and limited bioavailability. An understanding of the controlling features of this process was desired. The experimental module consisted of a bioreactor with synthetic endothelial-lined hollow fibers under flow. The physical design of the system was incorporated into the model parameters. The heparin-binding growth factor fibroblast growth factor-2 (FGF-2 was used for both the experiments and simulations. Our computational model was composed of three parts: (1 media flow equations, (2 mass transport equations and (3 cell surface reaction equations. The model is based on the flow and reactions within a single hollow fiber and was scaled linearly by the total number of fibers for comparison with experimental results. Our model predicted, and experiments confirmed, that removal of heparan sulfate (HS from the system would result in a dramatic loss of binding by heparin-binding proteins, but not by proteins that do not bind heparin. The model further predicted a significant loss of bound protein at flow rates only slightly higher than average capillary flow rates, corroborated experimentally, suggesting that the probability of capture in a single pass at high flow rates is extremely low. Several other key parameters were investigated with the coupling between receptors and proteoglycans shown to have a critical impact on successful capture. The combined system offers opportunities to examine circulation capture in a straightforward quantitative manner that

  14. Heparin-Binding EGF-like Growth Factor (HB-EGF) Therapy for Intestinal Injury: Application and Future Prospects

    Science.gov (United States)

    Yang, Jixin; Su, Yanwei; Zhou, Yu; Besner, Gail E.

    2014-01-01

    Throughout the past 20 years, we have been investigating the potential therapeutic roles of heparin-binding EGF-like growth factor (HB-EGF), a member of the epidermal growth factor family, in various models of intestinal injury including necrotizing enterocolitis (NEC), intestinal ischemia/reperfusion (I/R) injury, and hemorrhagic shock and resuscitation (HS/R). Our studies have demonstrated that HB-EGF acts as an effective mitogen, a restitution-inducing reagent, a cellular trophic factor, an anti-apoptotic protein and a vasodilator, via its effects on various cell types in the intestine. In the current paper, we have reviewed the application and therapeutic effects of HB-EGF in three classic animal models of intestinal injury, with particular emphasis on its protection of the intestines from NEC. Additionally, we have summarized the protective functions of HB-EGF on various target cells in the intestine. Lastly, we have provided a brief discussion focusing on the future development of HB-EGF clinical applications for the treatment of various forms of intestinal injury including NEC. PMID:24345808

  15. Human corpus luteum: presence of epidermal growth factor receptors and binding characteristics

    International Nuclear Information System (INIS)

    Ayyagari, R.R.; Khan-Dawood, F.S.

    1987-01-01

    Epidermal growth factor receptors are present in many reproductive tissues but have not been demonstrated in the human corpus luteum. To determine the presence of epidermal growth factor receptors and its binding characteristics, we carried out studies on the plasma cell membrane fraction of seven human corpora lutea (days 16 to 25) of the menstrual cycle. Specific epidermal growth factor receptors were present in human corpus luteum. Insulin, nerve growth factor, and human chorionic gonadotropin did not competitively displace epidermal growth factor binding. The optimal conditions for corpus luteum-epidermal growth factor receptor binding were found to be incubation for 2 hours at 4 degrees C with 500 micrograms plasma membrane protein and 140 femtomol 125 I-epidermal growth factor per incubate. The number (mean +/- SEM) of epidermal growth factor binding sites was 12.34 +/- 2.99 X 10(-19) mol/micrograms protein; the dissociation constant was 2.26 +/- 0.56 X 10(-9) mol/L; the association constant was 0.59 +/- 0.12 X 10(9) L/mol. In two regressing corpora lutea obtained on days 2 and 3 of the menstrual cycle, there was no detectable specific epidermal growth factor receptor binding activity. Similarly no epidermal growth factor receptor binding activity could be detected in ovarian stromal tissue. Our findings demonstrate that specific receptors for epidermal growth factor are present in the human corpus luteum. The physiologic significance of epidermal growth factor receptors in human corpus luteum is unknown, but epidermal growth factor may be involved in intragonadal regulation of luteal function

  16. Oxygen dependency of epidermal growth factor receptor binding and DNA synthesis of rat hepatocytes

    International Nuclear Information System (INIS)

    Hirose, Tetsuro; Terajima, Hiroaki; Yamauchi, Akira

    1997-01-01

    Background/Aims: Changes in oxygen availability modulate replicative responses in several cell types, but the effects on hepatocyte replication remain unclear. We have studied the effects of transient nonlethal hypoxia on epidermal growth factor receptor binding and epidermal growth factor-induced DNA synthesis of rat hepatocytes. Methods: Lactate dehydrogenase activity in culture supernatant, intracellular adenosine triphosphate content, 125 I-epidermal growth factor specific binding, epidermal growth factor receptor protein expression, and 3 H-thymidine incorporation were compared between hepatocytes cultured in hypoxia and normoxia. Results: Hypoxia up to 3 h caused no significant increase in lactate dehydrogenase activity in the culture supernatant, while intracellular adenosine triphosphate content decreased time-dependently and was restored to normoxic levels by reoxygenation (nonlethal hypoxia). Concomitantly, 125 I-epidermal growth factor specific binding to hepatocytes decreased time-dependently (to 54.1% of normoxia) and was restored to control levels by reoxygenation, although 125 I-insulin specific binding was not affected. The decrease in 125 I-epidermal growth factor specific binding was explained by the decrease in the number or available epidermal growth factor receptors (21.37±3.08 to 12.16±1.42 fmol/10 5 cells), while the dissociation constant of the receptor was not affected. The change in the number of available receptors was not considered to be due to receptor degradation-resynthesis, since immuno-detection of the epidermal growth factor receptor revealed that the receptor protein expression did not change during hypoxia and reoxygenation, and since neither actinomycin D nor cycloheximide affected the recovery of 125 I-epidermal growth factor binding by reoxygenation. Inhibition of epidermal growth factor-induced DNA synthesis after hypoxia (to 75.4% of normoxia by 3 h hypoxia) paralleled the decrease in 125 I-epidermal growth factor binding

  17. Sequence similarity between the erythrocyte binding domain of the Plasmodium vivax Duffy binding protein and the V3 loop of HIV-1 strain MN reveals a functional heparin binding motif involved in binding to the Duffy antigen receptor for chemokines

    Directory of Open Access Journals (Sweden)

    Bolton Michael J

    2011-11-01

    Full Text Available Abstract Background The HIV surface glycoprotein gp120 (SU, gp120 and the Plasmodium vivax Duffy binding protein (PvDBP bind to chemokine receptors during infection and have a site of amino acid sequence similarity in their binding domains that often includes a heparin binding motif (HBM. Infection by either pathogen has been found to be inhibited by polyanions. Results Specific polyanions that inhibit HIV infection and bind to the V3 loop of X4 strains also inhibited DBP-mediated infection of erythrocytes and DBP binding to the Duffy Antigen Receptor for Chemokines (DARC. A peptide including the HBM of PvDBP had similar affinity for heparin as RANTES and V3 loop peptides, and could be specifically inhibited from heparin binding by the same polyanions that inhibit DBP binding to DARC. However, some V3 peptides can competitively inhibit RANTES binding to heparin, but not the PvDBP HBM peptide. Three other members of the DBP family have an HBM sequence that is necessary for erythrocyte binding, however only the protein which binds to DARC, the P. knowlesi alpha protein, is inhibited by heparin from binding to erythrocytes. Heparitinase digestion does not affect the binding of DBP to erythrocytes. Conclusion The HBMs of DBPs that bind to DARC have similar heparin binding affinities as some V3 loop peptides and chemokines, are responsible for specific sulfated polysaccharide inhibition of parasite binding and invasion of red blood cells, and are more likely to bind to negative charges on the receptor than cell surface glycosaminoglycans.

  18. The heparin-binding site in tetranectin is located in the N-terminal region and binding does not involve the carbohydrate recognition domain.

    Science.gov (United States)

    Lorentsen, R H; Graversen, J H; Caterer, N R; Thogersen, H C; Etzerodt, M

    2000-04-01

    Tetranectin is a homotrimeric plasma and extracellular-matrix protein that binds plasminogen and complex sulphated polysaccharides including heparin. In terms of primary and tertiary structure, tetranectin is related to the collectin family of Ca(2+)-binding C-type lectins. Tetranectin is encoded in three exons. Exon 3 encodes the carbohydrate recognition domain, which binds to kringle 4 in plasminogen at low levels of Ca(2+). Exon 2 encodes an alpha-helix, which is necessary and sufficient to govern the trimerization of tetranectin by assembling into a triple-helical coiled-coil structural element. Here we show that the heparin-binding site in tetranectin resides not in the carbohydrate recognition domain but within the N-terminal region, comprising the 16 amino acid residues encoded by exon 1. In particular, the lysine residues in the decapeptide segment KPKKIVNAKK (tetranectin residues 6-15) are shown to be of primary importance in heparin binding.

  19. Isolation of non-heprin-binding and heparin-binding proteins of boar prostate

    Czech Academy of Sciences Publication Activity Database

    Maňásková, Pavla; Liberda, J.; Tichá, M.; Jonáková, Věra

    2002-01-01

    Roč. 770, - (2002), s. 137-143 ISSN 1570-0232. [International Symposium /2./ - Separation in the BioSciences. Praha, 17.09.2001-20.09.2001] R&D Projects: GA ČR GA303/99/0357; GA ČR GV524/96/K162 Institutional research plan: CEZ:AV0Z5052915 Keywords : isolation * prostatic proteins * heparin Subject RIV: CE - Biochemistry Impact factor: 1.913, year: 2002

  20. Mapping the heparin-binding site of the BMP antagonist gremlin by site-directed mutagenesis based on predictive modelling.

    Science.gov (United States)

    Tatsinkam, Arnold Junior; Mulloy, Barbara; Rider, Christopher C

    2015-08-15

    Gremlin is a member of the CAN (cerberus and DAN) family of secreted BMP (bone morphogenetic protein) antagonists and also an agonist of VEGF (vascular endothelial growth factor) receptor-2. It is critical in limb skeleton and kidney development and is re-expressed during tissue fibrosis. Gremlin binds strongly to heparin and heparan sulfate and, in the present study, we sought to investigate its heparin-binding site. In order to explore a putative non-contiguous binding site predicted by computational molecular modelling, we substituted a total of 11 key arginines and lysines located in three basic residue sequence clusters with homologous sequences from cerberus and DAN (differential screening selected gene abberative in neuroblastoma), CAN proteins which lack basic residues in these positions. A panel of six Myc-tagged gremlin mutants, MGR-1-MGR-6 (MGR, mutant gremlin), each containing different combinations of targeted substitutions, all showed markedly reduced affinity for heparin as demonstrated by their NaCl elution on heparin affinity chromatography, thus verifying our predictions. Both MGR-5 and MGR-6 retained BMP-4-binding activity comparable to that of wild-type gremlin. Low-molecular-mass heparin neither promoted nor inhibited BMP-4 binding. Finally, glutaraldehyde cross-linking demonstrated that gremlin forms non-covalent dimers, similar behaviour to that of DAN and also PRDC (protein related to cerberus and DAN), another CAN protein. The resulting dimer would possess two heparin-binding sites, each running along an exposed surface on the second β-strand finger loop of one of the monomers. © 2015 Authors; published by Portland Press Limited.

  1. Thermodynamic parameters associated with the binding of adrenalin and norephedrine to heparin

    International Nuclear Information System (INIS)

    Al-Ali, A.K.; Buchanan, J.D.; Power, D.M.; Butler, J.

    1983-01-01

    Pulse radiolysis has been used to determine the thermodynamic parameters (ΔG', ΔH' and ΔS') governing the binding of adrenalin and norephedrine to heparin. These complexes were completely dissociated by increasing concentrations of inorganic salts. Lower concentrations of divalent cations (e.g. Ca 2+ ) than of monovalent cations (e.g. Na + ) were necessary to effect dissociation of the complex. For each interaction an increase in drug binding occurred as the temperature was increased from ambient. However, a transition temperature was observed (48 0 C) above which the drug was progressively released as the temperature was increased. These observations are discussed in terms of conformational changes induced in the polymer below and above its melting temperature. (author)

  2. Activation of M1 macrophages in sepsis-induced acute kidney injury in response to heparin-binding protein.

    Directory of Open Access Journals (Sweden)

    Li Xing

    Full Text Available In the early stage of sepsis, M1 macrophages result in the production of inflammatory mediators and AKI. Heparin-binding protein (HBP have been shown to play important roles in sepsis-induced AKI. In this study, we investigate the association of HBP with M1 macrophages in sepsis-induced AKI.Male C57BL6 mice were subjected to cecal ligation and puncture (CLP or sham surgery. Biochemical and histological renal damage was assessed. Macrophage infiltration was assessed by immunohistochemistry. RT-PCR was used to investigate the expression of heparin-binding protein (HBP, the inducible nitric oxide synthase (iNOS and arginase 1 (Arg-1 mRNAs. Western blots were performed to assay the tissue levels of HBP, tumor necrosis factor alpha (TNF-α and interleukin-6 (IL-6.High levels of HBP were obviously detected 24 h after sepsis-induced AKI. Heparin inhibited HBP expression during sepsis-induced AKI. The suppression of HBP expression by heparin injection after the establishment of sepsis-induced AKI resulted in a reduction in renal injury severity accompanied with a significant repression of M1 macrophage activation and expression of TNF-α and IL-6.HBP plays an important role in the initial inflammatory reaction associated with sepsis-induced AKI, presumably by activating M1 macrophages and suppressing TNF-α and IL-6 secretion.

  3. Heparin-binding peptide as a novel affinity tag for purification of recombinant proteins.

    Science.gov (United States)

    Morris, Jacqueline; Jayanthi, Srinivas; Langston, Rebekah; Daily, Anna; Kight, Alicia; McNabb, David S; Henry, Ralph; Kumar, Thallapuranam Krishnaswamy Suresh

    2016-10-01

    Purification of recombinant proteins constitutes a significant part of the downstream processing in biopharmaceutical industries. Major costs involved in the production of bio-therapeutics mainly depend on the number of purification steps used during the downstream process. Affinity chromatography is a widely used method for the purification of recombinant proteins expressed in different expression host platforms. Recombinant protein purification is achieved by fusing appropriate affinity tags to either N- or C- terminus of the target recombinant proteins. Currently available protein/peptide affinity tags have proved quite useful in the purification of recombinant proteins. However, these affinity tags suffer from specific limitations in their use under different conditions of purification. In this study, we have designed a novel 34-amino acid heparin-binding affinity tag (HB-tag) for the purification of recombinant proteins expressed in Escherichia coli (E. coli) cells. HB-tag fused recombinant proteins were overexpressed in E. coli in high yields. A one-step heparin-Sepharose-based affinity chromatography protocol was developed to purify HB-fused recombinant proteins to homogeneity using a simple sodium chloride step gradient elution. The HB-tag has also been shown to facilitate the purification of target recombinant proteins from their 8 M urea denatured state(s). The HB-tag has been demonstrated to be successfully released from the fusion protein by an appropriate protease treatment to obtain the recombinant target protein(s) in high yields. Results of the two-dimensional NMR spectroscopy experiments indicate that the purified recombinant target protein(s) exist in the native conformation. Polyclonal antibodies raised against the HB-peptide sequence, exhibited high binding specificity and sensitivity to the HB-fused recombinant proteins (∼10 ng) in different crude cell extracts obtained from diverse expression hosts. In our opinion, the HB-tag provides a

  4. Elevated urine levels of heparin-binding protein in children with urinary tract infection.

    Science.gov (United States)

    Kjölvmark, Charlott; Akesson, Per; Linder, Adam

    2012-08-01

    Urinary tract infection (UTI) is a common infection diagnosis in children, and efficient diagnosis and treatment are important to avoid serious complications. In this study we investigated whether urinary levels of neutrophil-derived heparin-binding protein (HBP) can be used as a marker of UTI in children. These results were compared to those of dipstick analysis, interleukin-6 (IL-6) analysis in urine, and bacterial culturing. Seventy-eight children aged 0-18 years with fever and/or symptoms indicating UTI were enrolled in a prospective consecutive study. Urine samples were cultured and analyzed with dipstick, and concentrations of HBP and IL-6 were measured. Fifteen patients were classified as having UTI, 30 patients had fever but were diagnosed with a non-urinary tract infection, and 33 patients had neither UTI nor fever. Using a urine HBP (U-HBP) cut-off level of 32 ng/mL, the sensitivity and specificity for detecting UTI were 93.3 and 90.3 %, respectively. Receiver operating characteristic curves demonstrated that U-HBP levels were a higher specificity indicator of UTI than urine white blood cell counts or urine IL-6 levels; they also showed a higher sensitivity than the results of the urine nitrite test. All patients with significant growth of clinically relevant bacteria had elevated U-HBP levels. The results indicate that rapid analysis of U-HBP can provide helpful guidance in the management of children with suspected UTI.

  5. The N-terminal of a heparin-binding sperm membrane mitogen possess lectin-like sequence

    International Nuclear Information System (INIS)

    Mor, Visesato; Chatterjee, Tapati

    2007-01-01

    Glycosaminoglycans like heparin and heparin sulfate in follicular fluid induce changes in the intracellular environment during the spermatozoal functional maturation. We previously reported the isolation, purification and partial characterization of a heparin binding sperm membrane protein (HBSM). In the present study, the amino acids analysis provided evidence of a single sequence, which suggest the homogeneity of the purified HBSM. Fourteen amino acids- 1 A D T I V A V E L D T Y P N 14 -correspond to the amino terminal sequence of Concanavalin A (Con A) and contain 45.2% carbohydrate by weight. HBSM possess mitogenic property on lymphocytes with comparable magnitude to the well-known mitogen; Con A, inducing 83% radiolabel thymidine incorporation in growing lymphocytes. Unlike Con A, there was no agglutination of cell by HBSM upto 5 ng/ml concentration. Interestingly, we found that heparin and chondroitin sulfate-conjugated HBSM inhibit the proliferative activity. Similar effect was also found with an in-house isolate sulfated glycans; G-I (28% sulfate). In contrast, there was no inhibition by the desulfated form; G-ID. Altogether, our data suggest that the mechanism of cell proliferative pathway may be different for HBSM and Con A

  6. Lack of upregulation of epidermal fatty acid binding protein in dithranol induced irritation.

    NARCIS (Netherlands)

    Kucharekova, M.; Vissers, W.H.P.M.; Schalkwijk, J.; Kerkhof, P.C.M. van de; Valk, P.G.M. van der

    2003-01-01

    The exact role of epidermal fatty acid binding protein (E-FABP) in skin is unknown. A restoration of the barrier function may be associated with an upregulation of E-FABP. Moreover, E-FABP is upregulated in a variety of cells in response to oxidative stress. A recent observation that dithranol

  7. Sequence similarity between the erythrocyte binding domain of the Plasmodium vivax Duffy binding protein and the V3 loop of HIV-1 strain MN reveals a functional heparin binding motif involved in binding to the Duffy antigen receptor for chemokines

    OpenAIRE

    Bolton, Michael J; Garry, Robert F

    2011-01-01

    Abstract Background The HIV surface glycoprotein gp120 (SU, gp120) and the Plasmodium vivax Duffy binding protein (PvDBP) bind to chemokine receptors during infection and have a site of amino acid sequence similarity in their binding domains that often includes a heparin binding motif (HBM). Infection by either pathogen has been found to be inhibited by polyanions. Results Specific polyanions that inhibit HIV infection and bind to the V3 loop of X4 strains also inhibited DBP-mediated infectio...

  8. Comparative study of heparin-binding proteins profile of Murrah buffalo (Bubalus bubalis semen

    Directory of Open Access Journals (Sweden)

    S. S. Ramteke

    2014-09-01

    Full Text Available Aim: The experiment was conducted to study the total seminal plasma protein (TSPP and heparin-binding proteins (HBPs in relation to initial semen quality of buffalo bull. Materials and Methods: Semen from two Murrah buffalo bulls (bull no. 605 and 790 with mass motility of ≥3+ were used for the study and categorized into three groups (Group I- Mass motility 3+, Group II- Mass motility 4+ and Group III- Mass motility 5+. Seminal plasma from semen was separated by centrifugation. HBPs was isolated and purified from heparin-agarose affinity column by modified elution buffer. TSPP and isolated HBPs concentration was estimated by Lowry’s method. The purified HBPs were resolved on Sodium dodecyl sulfate polyacrylamide gel electrophoresis to check the protein profile of two bulls. Results: The mean values of TSPP concentrations in bull no. 605 and 790 in Group I, II and III were 30.64±0.12, 31.66±0.09, 32.53±0.19 and 28.51±0.09, 29.49±0.15, 30.45±0.17 mg/mL, respectively. The mean values of HBPs concentrations in bull no. 605 and 790 in Group I, II and III were 3.11±0.07, 3.32±0.06, 3.46±0.08 and 2.51±0.08, 2.91±0.05, 3.10±0.03 mg/mL, respectively. Both the values of TSPP and HBPs were significantly higher (p<0.01 in bull no. 605 when compared to 790 in all the three groups. 31 kDa HBP was more intensely present in bull no. 605, thus may indicate its superiority over bull no. 790 in relation to fertility potential. Conclusion: TSPP and HBPs shows variation in concentration with respect to initial semen quality. Furthermore, presence of fertility related 31 kDa HBPs in one of the bull may be an indication of high fertility of a bull. In future, in-vivo and in-vitro correlative study on larger basis is needed for the establishment of fertility-related HBPs in semen which might establish criteria for selection of buffalo bull with high fertility potential.

  9. The peanut lectin-binding glycoproteins of human epidermal keratinocytes

    International Nuclear Information System (INIS)

    Morrison, A.I.; Keeble, S.; Watt, F.M.

    1988-01-01

    The peanut lectin (PNA) is known to bind more strongly to keratinocytes that are undergoing terminal differentiation than to proliferating keratinocytes. In order to investigate the significance of this change in cell-surface carbohydrate authors have identified the PNA-binding glycoproteins of cultured human keratinocytes and antibodies against them. Two heavily glycosylated bands of 110 and 250 kDa were resolved by PAGE of [ 14 C]galactose- or [ 14 C]mannose- and [ 14 C]glucosamine-labeled cell extracts eluted with galactose from PNA affinity columns. The higher molecular weight band was also detected on PNA blots of unlabeled cell extracts transferred to nitrocellulose. Both bands were sensitive to pronase digestion, but only the 250-kDa band was digested with trypsin. A rabbit antiserum that we prepared (anti-PNA-gp) immunoprecipitated both bands from cell extracts. In contrast to PNA, anti-PNA-gp bound equally to proliferating and terminally differentiating cells, indicating that some epitope(s) of the PNA-binding glycoproteins is present on the cell surface prior to terminal differentiation. When keratinocytes grown as a monolayer in low-calcium medium were switched to medium containing 2 mM calcium ions in order to induce desmosome formation and stratification, there was a dramatic redistribution of the PNA-binding glycoproteins, which became concentrated at the boundaries between cells. This may suggest a role for the glycoproteins in cell-cell interactions during stratification

  10. Octasaccharide is the minimal length unit required for efficient binding of cyclophilin B to heparin and cell surface heparan sulphate.

    Science.gov (United States)

    Vanpouille, Christophe; Denys, Agnès; Carpentier, Mathieu; Pakula, Rachel; Mazurier, Joël; Allain, Fabrice

    2004-09-01

    Cyclophilin B (CyPB) is a heparin-binding protein first identified as a receptor for cyclosporin A. In previous studies, we reported that CyPB triggers chemotaxis and integrin-mediated adhesion of T-lymphocytes by way of interaction with two types of binding sites. The first site corresponds to a signalling receptor; the second site has been identified as heparan sulphate (HS) and appears crucial to induce cell adhesion. Characterization of the HS-binding unit is critical to understand the requirement of HS in pro-adhesive activity of CyPB. By using a strategy based on gel mobility shift assays with fluorophore-labelled oligosaccharides, we demonstrated that the minimal heparin unit required for efficient binding of CyPB is an octasaccharide. The mutants CyPB(KKK-) [where KKK- refers to the substitutions K3A(Lys3-->Ala)/K4A/K5A] and CyPB(DeltaYFD) (where Tyr14-Phe-Asp16 has been deleted) failed to interact with octasaccharides, confirming that the Y14FD16 and K3KK5 clusters are required for CyPB binding. Molecular modelling revealed that both clusters are spatially arranged so that they may act synergistically to form a binding site for the octasaccharide. We then demonstrated that heparin-derived octasaccharides and higher degree of polymerization oligosaccharides inhibited the interaction between CyPB and fluorophore-labelled HS chains purified from T-lymphocytes, and strongly reduced the HS-dependent pro-adhesive activity of CyPB. However, oligosaccharides or heparin were unable to restore adhesion of heparinase-treated T-lymphocytes, indicating that HS has to be present on the cell membrane to support the pro-adhesive activity of CyPB. Altogether, these results demonstrate that the octasaccharide is likely to be the minimal length unit required for efficient binding of CyPB to cell surface HS and consequent HS-dependent cell responses.

  11. A triad of lys12, lys41, arg78 spatial domain, a novel identified heparin binding site on tat protein, facilitates tat-driven cell adhesion.

    Directory of Open Access Journals (Sweden)

    Jing Ai

    Full Text Available Tat protein, released by HIV-infected cells, has a battery of important biological effects leading to distinct AIDS-associated pathologies. Cell surface heparan sulfate protoglycans (HSPGs have been accepted as endogenous Tat receptors, and the Tat basic domain has been identified as the heparin binding site. However, findings that deletion or substitution of the basic domain inhibits but does not completely eliminate Tat-heparin interactions suggest that the basic domain is not the sole Tat heparin binding site. In the current study, an approach integrating computational modeling, mutagenesis, biophysical and cell-based assays was used to elucidate a novel, high affinity heparin-binding site: a Lys12, Lys41, Arg78 (KKR spatial domain. This domain was also found to facilitate Tat-driven β1 integrin activation, producing subsequent SLK cell adhesion in an HSPG-dependent manner, but was not involved in Tat internalization. The identification of this new heparin binding site may foster further insight into the nature of Tat-heparin interactions and subsequent biological functions, facilitating the rational design of new therapeutics against Tat-mediated pathological events.

  12. The differences in heparin binding for the C-terminal basic-sequence-rich peptides of HPV-16 and HPV-18 capsid protein L1

    International Nuclear Information System (INIS)

    Sun Jian; Yu Jisheng; Yu Zhiwu; Zha Xiao; Wu Yuqing

    2012-01-01

    Graphial abstract: The differences in heparin binding for the C-terminal basic-sequence-rich peptides of HPV-16 and HPV-18 capsid protein L1. Highlights: ► Several driving forces contribute to the interaction between heparin and peptides. ► C-terminal of HPV L1 is a potential candidate for the attachment to host cells. ► The C-terminal peptides of HPV-16 and -18 L1 have different heparin-binding. ► The different heparin-binding provides an explanation for the distinct prevalences. - Abstract: The high-risk types of human papillomaviruses (HPV) HPV-16 and -18 are the predominant types associated with cervical cancer. HPV-16 and -18 account for about 50% and 20%, respectively, of cervical cancers worldwide. While the reason and molecular mechanism of the distinct prevalence and distributions between them remain poorly understood, the binding affinity of cell surface receptor with capsid proteins, especially L1, may be involved. We examined heparin binding with two synthetic peptides corresponding to the 14 amino acid C-terminal peptides of HPV-16 and -18 L1 with the goal of comparing the equivalent residues in different HPV types. Using isothermal titration calorimetry (ITC) and static right-angle light scattering (SLS), we determined the binding constant K, reaction enthalpy ΔH, and other thermodynamic parameters in the interaction. Especially, we assessed the role of specific residues in binding with heparin by comparing the NMR spectra of free and heparin-bound peptides.

  13. Heparin binding chitosan derivatives for production of pro-angiogenic hydrogels for promoting tissue healing

    Energy Technology Data Exchange (ETDEWEB)

    Yar, Muhammad, E-mail: drmyar@ciitlahore.edu.pk [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Shahzad, Sohail [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Shahzadi, Lubna [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Shahzad, Sohail Anjum [Department of Chemistry, COMSATS Institute of Information Technology, Abbottabad 22060 (Pakistan); Mahmood, Nasir [Department of Allied Health Sciences and Chemical Pathology, University of Health Sciences, Lahore (Pakistan); Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore (Pakistan); Chaudhry, Aqif Anwar [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Rehman, Ihtesham ur [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Materials Science and Engineering, North Campus, University of Sheffield, Broad Lane, Sheffield S3 7HQ (United Kingdom); MacNeil, Sheila, E-mail: s.macneil@sheffield.ac.uk [Materials Science and Engineering, North Campus, University of Sheffield, Broad Lane, Sheffield S3 7HQ (United Kingdom)

    2017-05-01

    Our aim was to develop a biocompatible hydrogel that could be soaked in heparin and placed on wound beds to improve the vasculature of poorly vascularized wound beds. In the current study, a methodology was developed for the synthesis of a new chitosan derivative (CSD-1). Hydrogels were synthesized by blending CSD-1 for either 4 or 24 h with polyvinyl alcohol (PVA). The physical/chemical interactions and the presence of specific functional groups were confirmed by Fourier transform infrared (FT-IR) spectroscopy and proton nuclear magnetic resonance ({sup 1}H NMR). The porous nature of the hydrogels was confirmed by scanning electron microscopy (SEM). Thermal gravimetric analysis (TGA) showed that these hydrogels have good thermal stability which was slightly increased as the blending time was increased. Hydrogels produced with 24 h of blending supported cell attachment more and could be loaded with heparin to induce new blood vessel formation in a chick chorionic allantoic membrane assay. - Highlights: • Chitosan based hydrogels were designed to stimulate angiogenesis. • Two new derivatives of chitosan were produced using a Mannich type reaction. • Blending a chitosan derivative with PVA gave a porous biocompatible hydrogel. • Heparin bound to the hydrogel on immersion changing its morphology. • Heparin loaded hydrogel stimulated blood vessel formation in a chick model.

  14. Role of the A+ helix in heparin binding to protein C inhibitor

    NARCIS (Netherlands)

    Elisen, M. G.; Maseland, M. H.; Church, F. C.; Bouma, B. N.; Meijers, J. C.

    1996-01-01

    Interactions between proteins and heparin(-like) structures involve electrostatic forces and structural features. Based on charge distributions in the linear sequence of protein C inhibitor (PCI), two positively charged regions of PCI were proposed as possible candidates for this interaction. The

  15. Altered [125I]epidermal growth factor binding and receptor distribution in psoriasis

    International Nuclear Information System (INIS)

    Nanney, L.B.; Stoscheck, C.M.; Magid, M.; King, L.E. Jr.

    1986-01-01

    Stimulation of growth and differentiation of human epidermis by epidermal growth factor (EGF) is mediated by its binding to specific receptors. Whether EGF receptors primarily mediate cell division or differentiation in hyperproliferative disease such as psoriasis vulgaris is unclear. To study the pathogenesis of psoriasis, 4-mm2 punch biopsy specimens of normal, uninvolved, and involved psoriatic skin were assayed for EGF receptors by autoradiographic, immunohistochemical, and biochemical methods. Using autoradiographic and immunohistochemical methods, basal keratinocytes were found to contain the greatest number of EGF binding sites and immunoreactive receptors as compared to the upper layers of the epidermis in both normal epidermis and psoriatic skin. No EGF receptor differences between normal and psoriatic epidermis were observed in this layer. In the upper layers of the epidermis, a 2-fold increase in EGF binding capacity was observed in psoriatic skin as compared with normal thin or thick skin. Biochemical methods indicated that [ 125 I]EGF binding was increased in psoriatic epidermis as compared with similar thickness normal epidermis when measured on a protein basis. Epidermal growth factor was shown to increase phosphorylation of the EGF receptor in skin. EGF receptors retained in the nonmitotic stratum spinosum and parakeratotic stratum corneum may reflect the incomplete, abnormal differentiation that occurs in active psoriatic lesions. Alternatively, retained EGF receptors may play a direct role in inhibiting cellular differentiation in the suprabasal layers

  16. Cell adhesion to fibrillin-1: identification of an Arg-Gly-Asp-dependent synergy region and a heparin-binding site that regulates focal adhesion formation

    DEFF Research Database (Denmark)

    Bax, Daniel V; Mahalingam, Yashithra; Cain, Stuart

    2007-01-01

    We have defined the molecular basis of cell adhesion to fibrillin-1, the major structural component of extracellular microfibrils that are associated with elastic fibres. Using human dermal fibroblasts, and recombinant domain swap fragments containing the Arg-Gly-Asp motif, we have demonstrated...... a requirement for upstream domains for integrin-alpha(5)beta(1)-mediated cell adhesion and migration. An adjacent heparin-binding site, which supports focal adhesion formation, was mapped to the fibrillin-1 TB5 motif. Site-directed mutagenesis revealed two arginine residues that are crucial for heparin binding...

  17. Insulin binding properties of normal and transformed human epidermal cultured keratinocytes

    International Nuclear Information System (INIS)

    Verrando, P.; Ortonne, J.P.

    1985-01-01

    Insulin binding to its receptors was studied in cultured normal and transformed (A431 line) human epidermal keratinocytes. The specific binding was a temperature-dependent, saturable process. Normal keratinocytes possess a mean value of about 80,000 receptors per cell. Fifteen hours exposure of the cells to insulin lowered their receptor number (about 65% loss in available sites); these reappeared when the hormone was removed from the culture medium. In the A431 epidermoid carcinoma cell line, there is a net decrease in insulin binding (84% of the initial bound/free hormone ratio in comparison with normal cells) essentially related to a loss in receptor affinity for insulin. Thus, cultured human keratinocytes which express insulin receptors may be a useful tool in understanding skin pathology related to insulin disorders

  18. Skin mucus of Cyprinus carpio inhibits cyprinid herpesvirus 3 binding to epidermal cells

    Directory of Open Access Journals (Sweden)

    Raj Victor

    2011-08-01

    Full Text Available Abstract Cyprinid herpesvirus 3 (CyHV-3 is the aetiological agent of a mortal and highly contagious disease in common and koi carp. The skin is the major portal of entry of CyHV-3 in carp after immersion in water containing the virus. In the present study, we used in vivo bioluminescence imaging to investigate the effect of skin mucus removal and skin epidermis lesion on CyHV-3 entry. Physical treatments inducing removal of the mucus up to complete erosion of the epidermis were applied on a defined area of carp skin just before inoculation by immersion in infectious water. CyHV-3 entry in carp was drastically enhanced on the area of the skin where the mucus was removed with or without associated epidermal lesion. To investigate whether skin mucus inhibits CyHV-3 binding to epidermal cells, tail fins with an intact mucus layer or without mucus were inoculated ex vivo. While electron microscopy examination revealed numerous viral particles bound on the fins inoculated after mucus removal, no particle could be detected after infection of mucus-covered fins. Finally, anti-CyHV-3 neutralising activity of mucus extract was tested in vitro. Incubation of CyHV-3 with mucus extract reduced its infectivity in a dose dependent manner. The present study demonstrates that skin mucus removal and epidermal lesions enhance CyHV-3 entry in carp. It highlights the role of fish skin mucus as an innate immune protection against viral epidermal entry.

  19. Skin mucus of Cyprinus carpio inhibits cyprinid herpesvirus 3 binding to epidermal cells

    Science.gov (United States)

    2011-01-01

    Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of a mortal and highly contagious disease in common and koi carp. The skin is the major portal of entry of CyHV-3 in carp after immersion in water containing the virus. In the present study, we used in vivo bioluminescence imaging to investigate the effect of skin mucus removal and skin epidermis lesion on CyHV-3 entry. Physical treatments inducing removal of the mucus up to complete erosion of the epidermis were applied on a defined area of carp skin just before inoculation by immersion in infectious water. CyHV-3 entry in carp was drastically enhanced on the area of the skin where the mucus was removed with or without associated epidermal lesion. To investigate whether skin mucus inhibits CyHV-3 binding to epidermal cells, tail fins with an intact mucus layer or without mucus were inoculated ex vivo. While electron microscopy examination revealed numerous viral particles bound on the fins inoculated after mucus removal, no particle could be detected after infection of mucus-covered fins. Finally, anti-CyHV-3 neutralising activity of mucus extract was tested in vitro. Incubation of CyHV-3 with mucus extract reduced its infectivity in a dose dependent manner. The present study demonstrates that skin mucus removal and epidermal lesions enhance CyHV-3 entry in carp. It highlights the role of fish skin mucus as an innate immune protection against viral epidermal entry. PMID:21816061

  20. Identifying the functional part of heparin-binding protein (HBP) as a monocyte stimulator and the novel role of monocytes as HBP producers

    DEFF Research Database (Denmark)

    Schou, Morten; Djurup, René; Norris, Kjeld

    2011-01-01

    Heparin-binding protein (HBP), an evolutionary ancient and biologically highly important molecule in inflammation, is an inactive serine protease due to mutations in the catalytic triad. The histidine (position 41) in the conserved sequence TAAHC is mutated to serine and this sequence (TAASC) pla...

  1. Alboserpin, a Factor Xa Inhibitor from the Mosquito Vector of Yellow Fever, Binds Heparin and Membrane Phospholipids and Exhibits Antithrombotic Activity

    Czech Academy of Sciences Publication Activity Database

    Calvo, E.; Mizurini, D.M.; Sa-Nunes, A.; Ribeiro, J.M.C.; Andersen, J. F.; Mans, B.J.; Monteiro, R.Q.; Kotsyfakis, Michalis; Francischetti, I.M.B.

    2011-01-01

    Roč. 286, č. 32 (2011), 27998-28010 ISSN 0021-9258 Institutional research plan: CEZ:AV0Z60220518 Keywords : serpin * mosquito * Aedes albopictus * phospholipids * Factor Xa * heparin * binding affinity * coagulation * thrombus * bleeding Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 4.773, year: 2011

  2. Covalent Binding of Heparin to Functionalized PET Materials for Improved Haemocompatibility

    Directory of Open Access Journals (Sweden)

    Metod Kolar

    2015-03-01

    Full Text Available The hemocompatibility of vascular grafts made from poly(ethylene terephthalate (PET is insufficient due to the rapid adhesion and activation of blood platelets that occur upon incubation with whole blood. PET polymer was treated with NHx radicals created by passing ammonia through gaseous plasma formed by a microwave discharge, which allowed for functionalization with amino groups. X-ray photoelectron spectroscopy characterization using derivatization with 4-chlorobenzaldehyde indicated that approximately 4% of the –NH2 groups were associated with the PET surface after treatment with the gaseous radicals. The functionalized polymers were coated with an ultra-thin layer of heparin and incubated with fresh blood. The free-hemoglobin technique, which is based on the haemolysis of erythrocytes, indicated improved hemocompatibility, which was confirmed by imaging the samples using confocal optical microscopy. A significant decrease in number of adhered platelets was observed on such samples. Proliferation of both human umbilical vein endothelial cells and human microvascular endothelial cells was enhanced on treated polymers, especially after a few hours of cell seeding. Thus, the technique represents a promising substitute for wet-chemical modification of PET materials prior to coating with heparin.

  3. Europium-labeled epidermal growth factor and neurotensin: novel probes for receptor-binding studies.

    Science.gov (United States)

    Mazor, Ohad; Hillairet de Boisferon, Marc; Lombet, Alain; Gruaz-Guyon, Anne; Gayer, Batya; Skrzydelsky, Delphine; Kohen, Fortune; Forgez, Patricia; Scherz, Avigdor; Rostene, William; Salomon, Yoram

    2002-02-01

    We investigated the possibility of labeling two biologically active peptides, epidermal growth factor (EGF) and neurotensin (NT), with europium (Eu)-diethylenetriaminepentaacetic acid. More specifically, we tested them as probes in studying receptor binding using time-resolved fluorescence of Eu3+. The relatively simple synthesis yields ligands with acceptable binding characteristics similar to isotopically labeled derivatives. The binding affinity (Kd) of labeled Eu-EGF to human A431 epidermal carcinoid cells was 3.6 +/- 1.2 nM, similar to the reported Kd values of EGF, whereas the Kd of Eu-NT to human HT29 colon cancer cells (7.4 +/- 0.5 nM) or to Chinese hamster ovary (CHO) cells transfected with the high-affinity NT receptor (CHO-NT1) were about 10-fold higher than the Kd values of NT. The bioactivity of the Eu-labeled EGF as determined by stimulation of cultured murine D1 hematopoietic cell proliferation was nearly the same as that obtained with native EGF. The maximal stimulation of Ca2+ influx with NT and Eu-NT in CHO-NT1 cells was similar, but the respective K0.5 values were 20 pM and 1 nM, corresponding to differences in the binding affinities previously described. The results of these studies indicate that Eu labeling of peptide hormones and growth factor molecules ranging from 10(3) to 10(5) Da can be conveniently accomplished. Importantly, the Eu-labeled products are stable for approximately 2 years and are completely safe for laboratory use compared to the biohazardous radioligands. Thus, Eu-labeled peptides present an attractive alternative for commonly used radiolabeled ligands in biological studies in general and in receptor assays in particular.

  4. GRHL3 binding and enhancers rearrange as epidermal keratinocytes transition between functional states.

    Directory of Open Access Journals (Sweden)

    Rachel Herndon Klein

    2017-04-01

    Full Text Available Transcription factor binding, chromatin modifications and large scale chromatin re-organization underlie progressive, irreversible cell lineage commitments and differentiation. We know little, however, about chromatin changes as cells enter transient, reversible states such as migration. Here we demonstrate that when human progenitor keratinocytes either differentiate or migrate they form complements of typical enhancers and super-enhancers that are unique for each state. Unique super-enhancers for each cellular state link to gene expression that confers functions associated with the respective cell state. These super-enhancers are also enriched for skin disease sequence variants. GRHL3, a transcription factor that promotes both differentiation and migration, binds preferentially to super-enhancers in differentiating keratinocytes, while during migration, it binds preferentially to promoters along with REST, repressing the expression of migration inhibitors. Key epidermal differentiation transcription factor genes, including GRHL3, are located within super-enhancers, and many of these transcription factors in turn bind to and regulate super-enhancers. Furthermore, GRHL3 represses the formation of a number of progenitor and non-keratinocyte super-enhancers in differentiating keratinocytes. Hence, chromatin relocates GRHL3 binding and enhancers to regulate both the irreversible commitment of progenitor keratinocytes to differentiation and their reversible transition to migration.

  5. Interactions between nattokinase and heparin/GAGs.

    Science.gov (United States)

    Zhang, Fuming; Zhang, Jianhua; Linhardt, Robert J

    2015-12-01

    Nattokinase (NK) is a serine protease extracted from a traditional Japanese food called natto. Due to its strong fibrinolytic and thrombolytic activity, NK is regarded as a valuable dietary supplement or nutraceutical for the oral thrombolytic therapy. In addition, NK has been investigated for some other medical applications including treatment of hypertension, Alzheimer's disease, and vitreoretinal disorders. The most widely used clinical anticoagulants are heparin and low molecular weight heparins. The interactions between heparin and proteins modulate diverse patho-physiological processes and heparin modifies the activity of serine proteases. Indeed, heparin plays important roles in almost all of NK's potential therapeutically applications. The current report relies on surface plasmon resonance spectroscopy to examine NK interacting with heparin as well as other glycosaminoglycans (GAGs). These studies showed that NK is a heparin binding protein with an affinity of ~250 nM. Examination with differently sized heparin oligosaccharides indicated that the interaction between NK and heparin is chain-length dependent and the minimum size for heparin binding is a hexasaccharide. Studies using chemically modified heparin showed the 6-O-sulfo as well as the N-sulfo groups but not the 2-O-sulfo groups within heparin, are essential for heparin's interaction with NK. Other GAGs (including HS, DS, and CSE) displayed modest binding affinity to NK. NK also interfered with other heparin-protein interactions, including heparin's interaction with antithrombin and fibroblast growth factors.

  6. Molecular determinants of epidermal growth factor binding: a molecular dynamics study.

    Directory of Open Access Journals (Sweden)

    Jeffrey M Sanders

    Full Text Available The epidermal growth factor receptor (EGFR is a member of the receptor tyrosine kinase family that plays a role in multiple cellular processes. Activation of EGFR requires binding of a ligand on the extracellular domain to promote conformational changes leading to dimerization and transphosphorylation of intracellular kinase domains. Seven ligands are known to bind EGFR with affinities ranging from sub-nanomolar to near micromolar dissociation constants. In the case of EGFR, distinct conformational states assumed upon binding a ligand is thought to be a determining factor in activation of a downstream signaling network. Previous biochemical studies suggest the existence of both low affinity and high affinity EGFR ligands. While these studies have identified functional effects of ligand binding, high-resolution structural data are lacking. To gain a better understanding of the molecular basis of EGFR binding affinities, we docked each EGFR ligand to the putative active state extracellular domain dimer and 25.0 ns molecular dynamics simulations were performed. MM-PBSA/GBSA are efficient computational approaches to approximate free energies of protein-protein interactions and decompose the free energy at the amino acid level. We applied these methods to the last 6.0 ns of each ligand-receptor simulation. MM-PBSA calculations were able to successfully rank all seven of the EGFR ligands based on the two affinity classes: EGF>HB-EGF>TGF-α>BTC>EPR>EPG>AR. Results from energy decomposition identified several interactions that are common among binding ligands. These findings reveal that while several residues are conserved among the EGFR ligand family, no single set of residues determines the affinity class. Instead we found heterogeneous sets of interactions that were driven primarily by electrostatic and Van der Waals forces. These results not only illustrate the complexity of EGFR dynamics but also pave the way for structure-based design of

  7. Distribution of epidermal growth factor binding sites in the adult rat anterior pituitary gland

    International Nuclear Information System (INIS)

    Chabot, J.G.; Walker, P.; Pelletier, G.

    1986-01-01

    The distribution of epidermal growth (EGF) binding sites was studied in the pituitary gland using light and electron microscope autoradiography which was performed at different time intervals (2 to 60 min) after intravenous (IV) injection of [ 125 I]EGF into adult rats. At the light microscopic level, the labeling was found over cells of the anterior pituitary gland. The time-course study performed by light microscope autoradiography showed that the maximal values were reached at the 2 min time interval. At this time interval, most silver grains were found at the periphery of the target cells. After, the number of silver grains decreased progressively and the localization of silver grains in the cytoplasm indicated the internalization of [ 125 I]EGF. Electron microscope autoradiography showed that labeling was mostly restricted to mammotrophs and somatotrophs. Control experiments indicated that the autoradiographic labeling was due specific interaction of [ 125 I]EGF with its binding site. These results indicate that EGF binding sites are present in at least two anterior pituitary cell types and suggest that EGF can exert a physiological role in the pituitary gland

  8. Enantiomeric and Diastereomeric Self-Assembled Multivalent (SAMul) Nanostructures - Understanding the Effects of Chirality on Binding to Polyanionic Heparin and DNA.

    Science.gov (United States)

    Thornalley, Kiri; Laurini, Erik; Pricl, Sabrina; Smith, David K

    2018-05-15

    A family of four self-assembling lipopeptides containing Ala-Lys peptides attached to a C16 aliphatic chain was synthesised. These compounds form two enantiomeric pairs that bear a diastereomeric relationship to one another (C16-L-Ala-L-Lys/C16-D-Ala-D-Lys) and (C16-D-Ala-L-Lys/C16-L-Ala-D-Lys). These diastereomeric pairs have very different critical micelle concentrations (CMCs), with LL/DD < DL/LD suggesting more effective assembly of the former. The self-assembled multivalent (SAMul) systems bind biological polyanions as result of the cationic lysine groups on their surfaces. Polyanion binding was investigated using dye displacement assays and isothermal calorimetry (ITC). On heparin binding, there was no significant enantioselectivity, but there was a binding preference for the diastereomeric assemblies with lower CMCs. Conversely, on binding DNA, there was a significant enantioselective preference for systems displaying D-lysine ligands, with a further slight preference for attachment to L-alanine, with the CMC being irrelevant. Binding to adaptive, ill-defined heparin has a large favourable entropic term, suggesting it depends primarily on the cationic SAMul nanostructure maximising surface contact with heparin, which can adapt, displacing solvent and other ions. Conversely, binding to well-defined, shape-persistent DNA has a larger favourable enthalpic term, and combined with the enantioselectivity, this allows us to suggest that its SAMul binding is based on optimised individual electrostatic interactions at the molecular level, with a preference for binding to D-lysine. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Rat embryo fibroblasts require both the cell-binding and the heparin-binding domains of fibronectin for survival

    DEFF Research Database (Denmark)

    Jeong, J; Han, I; Lim, Y

    2001-01-01

    of the cell-binding domain of FN with integrin is sufficient to rescue rat embryo fibroblasts (REFs) from detachment-induced apoptosis. REFs attached and spread normally after plating on substrates coated with either intact FN or a FN fragment, FN120, that contains the cell-binding domain but lacks the C...

  10. Heparin kinetics

    International Nuclear Information System (INIS)

    Swart, C.A.M. de.

    1983-01-01

    The author has studied the kinetics of heparin and heparin fractions after intravenous administration in humans and in this thesis the results of this study are reported. Basic knowledge about the physico-chemical properties of heparin and its interactions with proteins resulting in anticoagulant and lipolytic effects are discussed in a review (chapter II), which also comprises some clinical aspects of heparin therapy. In chapter III the kinetics of the anticoagulant effect are described after intravenous administration of five commercial heparin preparations. A mathematical model is presented that fits best to these kinetics. The kinetics of the anticoagulant and lipolytic effects after intravenous injection of various 35 S-radiolabelled heparin fractions and their relationship with the disappearance of the radiolabel are described in chapter IV. Chapter V gives a description of the kinetics of two radiolabels after injection of in vitro formed complexes consisting of purified, 125 I-radiolabelled antithrombin III and various 35 S-radiolabelled heparin fractions. (Auth.)

  11. Demonstration of epidermal growth factor binding sites in the adult rat pancreas by light microscopic autoradiography

    International Nuclear Information System (INIS)

    Chabot, J.G.; Walker, P.; Pelletier, G.

    1987-01-01

    The distribution of epidermal growth factor (EGF) receptors was studied in the pancreas using light microscopic autoradiography, which was performed at different time intervals (2-60 min) after injecting 125 I-labeled EGF intravenously into the adult rat. In the exocrine pancreas, a labeling was found to occur over the pyramidal cells of the acini and cells lining the intercalated ducts. Moreover, substantial binding of EGF to cells of the islets of Langerhans was also revealed. At the 2-min time interval, most silver grains were found at the periphery of the target cells. The localization, as well as the diminution of silver grains over the cytoplasm of these cells, between 7 and 60 min, suggested the internalization and degradation of 125 I-labeled EGF. Control experiments indicated that the autoradiography reaction was due to specific interaction of 125 I-labeled EGF with its receptor. These results clearly indicate that EGF receptors are present in the acinar cells and the cells of intercalated ducts of the exocrine pancreas, as well as the cells of the endocrine pancreas. Finding that there are EGF binding sites in pancreatic acinar cells supports the physiological role of EGF in the regulation of pancreatic exocrine function. The presence of EGF receptors in cells of the islets of Langerhans suggests that EGF may play a role in the regulation of the endocrine pancreas

  12. Heparin (GAG-hed) inhibits LCR activity of Human Papillomavirus type 18 by decreasing AP1 binding

    International Nuclear Information System (INIS)

    Villanueva, Rita; Morales-Peza, Néstor; Castelán-Sánchez, Irma; García-Villa, Enrique; Tapia, Rocio; Cid-Arregui, Ángel; García-Carrancá, Alejandro; López-Bayghen, Esther; Gariglio, Patricio

    2006-01-01

    High risk HPVs are causative agents of anogenital cancers. Viral E6 and E7 genes are continuously expressed and are largely responsible for the oncogenic activity of these viruses. Transcription of the E6 and E7 genes is controlled by the viral Long Control Region (LCR), plus several cellular transcription factors including AP1 and the viral protein E2. Within the LCR, the binding and activity of the transcription factor AP1 represents a key regulatory event in maintaining E6/E7 gene expression and uncontrolled cell proliferation. Glycosaminoglycans (GAGs), such as heparin, can inhibit tumour growth; they have also shown antiviral effects and inhibition of AP1 transcriptional activity. The purpose of this study was to test the heparinoid GAG-hed, as a possible antiviral and antitumoral agent in an HPV18 positive HeLa cell line. Using in vivo and in vitro approaches we tested GAG-hed effects on HeLa tumour cell growth, cell proliferation and on the expression of HPV18 E6/E7 oncogenes. GAG-hed effects on AP1 binding to HPV18-LCR-DNA were tested by EMSA. We were able to record the antitumoral effect of GAG-hed in vivo by using as a model tumours induced by injection of HeLa cells into athymic female mice. The antiviral effect of GAG-hed resulted in the inhibition of LCR activity and, consequently, the inhibition of E6 and E7 transcription. A specific diminishing of cell proliferation rates was observed in HeLa but not in HPV-free colorectal adenocarcinoma cells. Treated HeLa cells did not undergo apoptosis but the percentage of cells in G 2 /M phase of the cell cycle was increased. We also detected that GAG-hed prevents the binding of the transcription factor AP1 to the LCR. Direct interaction of GAG-hed with the components of the AP1 complex and subsequent interference with its ability to correctly bind specific sites within the viral LCR may contribute to the inhibition of E6/E7 transcription and cell proliferation. Our data suggest that GAG-hed could have

  13. A mutation in the heparin-binding site of noggin as a novel mechanism of proximal symphalangism and conductive hearing loss.

    Science.gov (United States)

    Masuda, Sawako; Namba, Kazunori; Mutai, Hideki; Usui, Satoko; Miyanaga, Yuko; Kaneko, Hiroki; Matsunaga, Tatsuo

    2014-05-09

    The access of bone morphogenetic protein (BMP) to the BMP receptors on the cell surface is regulated by its antagonist noggin, which binds to heparan-sulfate proteoglycans on the cell surface. Noggin is encoded by NOG and mutations in the gene are associated with aberrant skeletal formation, such as in the autosomal dominant disorders proximal symphalangism (SYM1), multiple synostoses syndrome, Teunissen-Cremers syndrome, and tarsal-carpal coalition syndrome. NOG mutations affecting a specific function may produce a distinct phenotype. In this study, we investigated a Japanese pedigree with SYM1 and conductive hearing loss and found that it carried a novel heterozygous missense mutation of NOG (c.406C>T; p.R136C) affecting the heparin-binding site of noggin. As no mutations of the heparin-binding site of noggin have previously been reported, we investigated the crystal structure of wild-type noggin to investigate molecular mechanism of the p.R136C mutation. We found that the positively charged arginine at position 136 was predicted to be important for binding to the negatively charged heparan-sulfate proteoglycan (HSPG). An in silico docking analysis showed that one of the salt bridges between noggin and heparin disappeared following the replacement of the arginine with a non-charged cysteine. We propose that the decreased binding affinity of NOG with the p.R136C mutation to HSPG leads to an excess of BMP signaling and underlies the SYM1 and conductive hearing loss phenotype of carriers. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Pharmacological inhibition of heparin-binding EGF-like growth factor promotes peritoneal angiogenesis in a peritoneal dialysis rat model.

    Science.gov (United States)

    Li, Zhenyuan; Yan, Hao; Yuan, Jiangzi; Cao, Liou; Lin, Aiwu; Dai, Huili; Ni, Zhaohui; Qian, Jiaqi; Fang, Wei

    2018-04-01

    Molecular mechanisms of peritoneal dialysis (PD) ultrafiltration failure, peritoneal neo-angiogenesis, and fibrosis remain to be determined. We aimed to determine the role of heparin-binding EGF-like growth factor (HB-EGF) inhibition on angiogenesis of peritoneal membrane in a PD rat model. 32 male Wistar rats were assigned into (1) control group; (2) uremic non-PD group: subtotal nephrectomy-induced uremic rats without PD; (3) uremic rats subjected to PD: uremic rats that were dialyzed with Dianeal ® for 4 weeks; (4) CRM 197 group: dialyzed uremic rats were supplemented with CRM197, a specific HB-EGF inhibitor. Peritoneal transport function was examined by peritoneal equilibration test. Expression of HB-EGF and EGFR in peritoneal samples were examined by real-time PCR, immunohistochemical staining, and western blot. Progressive angiogenesis and fibrosis were observed in uremic PD rats, and there were associated with decreased net ultrafiltration (nUF), increased permeability of peritoneal membrane, and reduced expression of HB-EGF and EGFR protein and mRNA in uremic PD rats compared to uremic non-PD or control groups (both p CRM197 significantly induced peritoneal membrane permeability, decreased nUF, increased higher vessel density, and reduced pericyte count compared to that of uremic PD rats. The levels of HB-EGF and EGFR expression negatively correlated with vessel density in peritoneal membrane (both p < 0.001). PD therapy was associated with peritoneal angiogenesis, functional deterioration, and downregulation of HB-EGF/EGFR. Pharmacological inhibition of HB-EGF promoted PD-induced peritoneal angiogenesis and fibrosis and ultrafiltration decline, suggesting that HB-EGF downregulation contributes to peritoneal functional deterioration in the uremic PD rat model.

  15. The heparin-binding domain of HB-EGF as an efficient cell-penetrating peptide for drug delivery.

    Science.gov (United States)

    Luo, Zhao; Cao, Xue-Wei; Li, Chen; Wu, Miao-Dan; Yang, Xu-Zhong; Zhao, Jian; Wang, Fu-Jun

    2016-11-01

    Cell-penetrating peptides (CPPs) have been shown to be potential drug carriers for cancer therapy. The inherently low immunogenicity and cytotoxicity of human-derived CPPs make them more suitable for intracellular drug delivery compared to other delivery vehicles. In this work, the protein transduction ability of a novel CPP (termed HBP) derived from the heparin-binding domain of HB-EGF was evaluated. Our data shows, for the first time, that HBP possesses similar properties to typical CPPs and is a potent drug delivery vector for improving the antitumor activity of impermeable MAP30. The intrinsic bioactivities of recombinant MAP30-HBP were well preserved compared to those of free MAP30. Furthermore, HBP conjugated to the C-terminus of MAP30 promoted the cellular uptake of recombinant MAP30-HBP. Moreover, the fusion of HBP to MAP30 gave rise to significantly enhanced cytotoxic effects in all of the tumor cell lines tested. In HeLa cells, this cytotoxicity was mainly caused by the induction of cell apoptosis. Further investigation revealed that HBP enhanced MAP30-induced apoptosis through the activation of the mitochondrial- and death receptor-mediated signaling pathways. In addition, the MAP30-HBP fusion protein caused more HeLa cells to become arrested in S phase compared to MAP30 alone. These results highlight the MAP30-HBP fusion protein as a promising drug candidate for cancer therapy and demonstrate HBP, a novel CPP derived from human HB-EGF, as a new potential vector for antitumor drug delivery. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

  16. Epidermal growth factor treatment of A431 cells alters the binding capacity and electrophoretic mobility of the cytoskeletally associated epidermal growth factor receptor

    International Nuclear Information System (INIS)

    Roy, L.M.; Gittinger, C.K.; Landreth, G.E.

    1991-01-01

    Epidermal growth factor receptor interacts with structural elements of A431 cells and remains associated with the cytoskeleton following extraction with nonionic detergents. Extraction of cells with 0.15% Triton X-100 resulted in detection of only approximately 40% of the EGF binding sites on the cytoskeleton. If the cells were exposed to EGF prior to extraction, approximately twofold higher levels of low-affinity EGF binding sites were detected. The difference in number of EGF binding sites was not a consequence of differences in numbers of EGF receptors associated with the cytoskeleton; equal amounts of 35S-labeled receptor were immunoprecipitated from the cytoskeletons of both control and EGF-treated cells. The effect of EGF pretreatment on binding activity was coincident with a change in the mobility of the receptor from a doublet of Mr approximately 160-180 kDa to a single sharp band at 180 kDa. The alteration in receptor mobility was not a simple consequence of receptor phosphorylation in that the alteration was not reversed by alkaline phosphatase treatment, nor was the shift produced by treatment of the cells with phorbol ester. The two EGF receptor species demonstrated differential susceptibility to V8 proteinase digestion. The EGF-induced 180 kDa species was preferentially digested by the proteinase relative to the 160 kDa species, indicating that EGF binding results in a conformational change in the receptor. The EGF-mediated preservation of binding activity and altered conformation may be related to receptor oligomerization

  17. The heparin-binding domain of HB-EGF mediates localization to sites of cell-cell contact and prevents HB-EGF proteolytic release

    Energy Technology Data Exchange (ETDEWEB)

    Prince, Robin N.; Schreiter, Eric R.; Zou, Peng; Wiley, H. S.; Ting, Alice Y.; Lee, Richard T.; Lauffenburger, Douglas A.

    2010-07-01

    Heparin-binding EGF-like growth factor (HB-EGF) is a ligand for EGF receptor (EGFR) and possesses the ability to signal in juxtacrine, autocrine and/or paracrine mode, with these alternatives being governed by the degree of proteolytic release of the ligand. Although the spatial range of diffusion of released HB-EGF is restricted by binding heparan-sulfate proteoglycans (HSPGs) in the extracellular matrix and/or cellular glycocalyx, ascertaining mechanisms governing non-released HB-EGF localization is also important for understanding its effects. We have employed a new method for independently tracking the localization of the extracellular EGFlike domain of HB-EGF and the cytoplasmic C-terminus. A striking observation was the absence of the HB-EGF transmembrane proform from the leading edge of COS-7 cells in a wound-closure assay; instead, this protein localized in regions of cell-cell contact. A battery of detailed experiments found that this localization derives from a trans interaction between extracellular HSPGs and the HBEGF heparin-binding domain, and that disruption of this interaction leads to increased release of soluble ligand and a switch in cell phenotype from juxtacrine-induced growth inhibition to autocrine-induced proliferation. Our results indicate that extracellular HSPGs serve to sequester the transmembrane pro-form of HB-EGF at the point of cell-cell contact, and that this plays a role in governing the balance between juxtacrine versus autocrine and paracrine signaling.

  18. Cellular adhesion responses to the heparin-binding (HepII) domain of fibronectin require heparan sulfate with specific properties

    DEFF Research Database (Denmark)

    Mahalingam, Yashithra; Gallagher, John T; Couchman, John R

    2006-01-01

    of fibronectin (HepII domain) through its HS chains. The fine structure of HS is critical to growth factor responses, and whether this extends to matrix ligands is unknown but is suggested from in vitro experiments. Cell attachment to HepII showed that heparin oligosaccharides of >or=14 sugar residues were...

  19. Differences in human skin between the epidermal growth factor receptor distribution detected by EGF binding and monoclonal antibody recognition

    DEFF Research Database (Denmark)

    Green, M R; Couchman, J R

    1985-01-01

    , the eccrine sweat glands, capillary system, and the hair follicle outer root sheath, generally similar in pattern to that previously reported for full-thickness rat skin and human epidermis. The same areas also bound EGF-R1 but in addition the monoclonal antibody recognized a cone of melanin containing......Two methods have been used to examine epidermal growth factor (EGF) receptor distribution in human scalp and foreskin. The first employed [125I]EGF viable explants and autoradiography to determine the EGF binding pattern while the second used a monoclonal antibody to the human EGF receptor to map...... whether EGF-R1 could recognize molecules unrelated to the EGF receptor, the EGF binding and EGF-R1 recognition profiles were compared on cultures of SVK14 cells, a SV40 transformed human keratinocyte cell line. EGF binding and EGF-R1 monoclonal antibody distribution on these cells was found to be similar...

  20. Conformational stability of the epidermal growth factor (EGF) receptor as influenced by glycosylation, dimerization and EGF hormone binding.

    Science.gov (United States)

    Taylor, Eric S; Pol-Fachin, Laercio; Lins, Roberto D; Lower, Steven K

    2017-04-01

    The epidermal growth factor receptor (EGFR) is an important transmembrane glycoprotein kinase involved the initiation or perpetuation of signal transduction cascades within cells. These processes occur after EGFR binds to a ligand [epidermal growth factor (EGF)], thus inducing its dimerization and tyrosine autophosphorylation. Previous publications have highlighted the importance of glycosylation and dimerization for promoting proper function of the receptor and conformation in membranes; however, the effects of these associations on the protein conformational stability have not yet been described. Molecular dynamics simulations were performed to characterize the conformational preferences of the monomeric and dimeric forms of the EGFR extracellular domain upon binding to EGF in the presence and absence of N-glycan moieties. Structural stability analyses revealed that EGF provides the most conformational stability to EGFR, followed by glycosylation and dimerization, respectively. The findings also support that EGF-EGFR binding takes place through a large-scale induced-fitting mechanism. Proteins 2017; 85:561-570. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. The ligand-binding profile of HARE: hyaluronan and chondroitin sulfates A, C, and D bind to overlapping sites distinct from the sites for heparin, acetylated low-density lipoprotein, dermatan sulfate, and CS-E.

    Science.gov (United States)

    Harris, Edward N; Weigel, Paul H

    2008-08-01

    The hyaluronic acid receptor for endocytosis (HARE)/ Stabilin-2 is the primary systemic scavenger receptor for hyaluronan (HA), the chondroitin sulfates (CS), dermatan sulfate (DS), and nonglycosaminoglycan (GAG) ligands such as acetylated low-density lipoprotein (AcLDL), pro-collagen propeptides, and advanced glycation end products. We recently discovered that HARE is also a systemic scavenger receptor for heparin (Hep) (Harris EN, Weigel JA, Weigel PH. 2008. The human hyaluronan receptor for endocytosis [HARE/Stabilin-2] is a systemic clearance receptor for heparin. J Biol Chem. 283:17341-17350). Our goal was to map the binding sites of eight different ligands within HARE. We used biotinylated GAGs and radio-iodinated streptavidin or AcLDL to assess the binding activities of ligands directly or indirectly (by competition with unlabeled ligands) in endocytosis assays using stable cell lines expressing the 315 or 190 kDa HA receptor for endocytosis (315- or 190-HARE) isoforms, and ELISA-like assays, with purified recombinant soluble 190-HARE ecto-domain. For example, Hep binding to HARE was competed by DS, CS-E, AcLDL, and dextran sulfate, but not by other CS types, HA, dextran, or heparosan. (125)I-AcLDL binding to HARE was partially competed by Hep and dextran sulfate, but not competed by HA. Two ligands, DS and CS-E, competed with both Hep and HA to some degree. Hep and HA binding or endocytosis is mutually inclusive; binding of these two GAGs occurs with functionally separate, noncompetitive, and apparently noninteracting domains. Thus, HARE binds to HA and Hep simultaneously. Although the domain(s) responsible for Hep binding remains unknown, the Link domain was required for HARE binding to HA, CS-A, CS-C, and CS-D. These results enable us to outline, for the first time, a binding activity map for multiple ligands of HARE.

  2. 125I-human epidermal growth factor specific binding to placentas and fetal membranes from varoius pregnancy states

    International Nuclear Information System (INIS)

    Hofmann, G.E.; Siddiqi, T.A.; Rao, Ch. V.; Carman, F.R.

    1988-01-01

    Specific binding of 125 I-human epidermal growth factor (hEGF) to homogenates of term human placentas and fetal membranes from normal and appropriate for gestational age (N = 20), intrauterine growth retarded (N = 9), twin (N = 11), White class A/B diabetic (N = 12), and large for gestational age (N = 13) pregnancies was measured. In all pregnancy states, placentas bound approximately four times more 125 I-hEGF than did fetal membranes (P 125 I-hEGF binding to fetal membranes from the various pregnancy states (P 125 I-hEGF specific binding to placentas from intrauterine growth retarded or twin pregnancies was significantly greater compared with placentas from normal and appropriate for gestational age pregnancies (P 125 I-hEGF specific binding did not differ between placentas from intrauterine growth retarded or twin pregnancies (P 125 I-hEGF binding did not vary with fetal sex, maternal race, placental weight, or gestational age between 37 to 42 weeks (P 125 I-hEGF binding increased with increasing infant weight when appropriate for gestational age and large for gestational age infants were included (P<0.05, r = 0.38, N = 32) but not for intrauterine growth retarded, appropriate for gestational age, or large for gestational age infants alone. (author)

  3. N-terminal and C-terminal heparin-binding domain polypeptides derived from fibronectin reduce adhesion and invasion of liver cancer cells

    International Nuclear Information System (INIS)

    Tang, Nan-Hong; Chen, Yan-Lin; Wang, Xiao-Qian; Li, Xiu-Jin; Wu, Yong; Zou, Qi-Lian; Chen, Yuan-Zhong

    2010-01-01

    Fibronectin (FN) is known to be a large multifunction glycoprotein with binding sites for many substances, including N-terminal and C-terminal heparin-binding domains. We investigated the effects of highly purified rhFNHN29 and rhFNHC36 polypeptides originally cloned from the two heparin-binding domains on the adhesion and invasion of highly metastatic human hepatocellular carcinoma cells (MHCC97H) and analyzed the underlying mechanism involved. The MHCC97H cells that adhered to FN in the presence of various concentrations of rhFNHN29 and rhFNHC36 polypeptides were stained with crystal violet and measured, and the effects of rhFNHN29 and rhFNHC36 on the invasion of the MHCC97H cells were then detected using the Matrigel invasion assay as well as a lung-metastasis mouse model. The expression level of integrins and focal adhesion kinase (FAK) phosphotyrosyl protein was examined by Western blot, and the activity of matrix metalloproteinases (MMPs) and activator protein 1 (AP-1) was analyzed by gelatin zymography and the electrophoretic mobility band-shift assay (EMSA), respectively. Both of the polypeptides rhFNHN29 and rhFNHC36 inhibited adhesion and invasion of MHCC97H cells; however, rhFNHC36 exhibited inhibition at a lower dose than rhFNHN29. These inhibitory effects were mediated by integrin αvβ3 and reversed by a protein tyrosine phosphatase inhibitor. Polypeptides rhFNHN29 and rhFNHC36 abrogated the tyrosine phosphorylation of focal adhesion kinase (p-FAK) and activation of activator protein 1 (AP-1), resulting in the decrease of integrin αv, β3 and β1 expression as well as the reduction of MMP-9 activity. Polypeptides rhFNHN29 and rhFNHC36 could potentially be applicable to human liver cancer as anti-adhesive and anti-invasive agents

  4. /sup 125/I-human epidermal growth factor specific binding to placentas and fetal membranes from varoius pregnancy states

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, G.E.; Siddiqi, T.A.; Rao, Ch. V.; Carman, F.R.

    1988-01-01

    Specific binding of /sup 125/I-human epidermal growth factor (hEGF) to homogenates of term human placentas and fetal membranes from normal and appropriate for gestational age (N = 20), intrauterine growth retarded (N = 9), twin (N = 11), White class AB diabetic (N = 12), and large for gestational age (N = 13) pregnancies was measured. In all pregnancy states, placentas bound approximately four times more /sup 125/I-hEGF than did fetal membranes (P<0.0001). There was no significant differnce in /sup 125/I-hEGF binding to fetal membranes from the various pregnancy states (P<0.05). /sup 125/I-hEGF specific binding to placentas from intrauterine growth retarded or twin pregnancies was significantly greater compared with placentas from normal and appropriate for gestational age pregnancies (P<0.05). The binding to placentas from pregnancies complicated by White class AB diabetes or large for gestational age infants, on the other hand, was not significantly different from that to placentas from normal and appropriate for gestational age pregnancies. /sup 125/I-hEGF specific binding did not differ between placentas from intrauterine growth retarded or twin pregnancies (P<0.05). Placental and fetal membrane /sup 125/I-hEGF binding did not vary with fetal sex, maternal race, placental weight, or gestational age between 37 to 42 weeks (P<0.05). Placental but not fetal membrane /sup 125/I-hEGF binding increased with increasing infant weight when appropriate for gestational age and large for gestational age infants were included (P<0.05, r = 0.38, N = 32) but not for intrauterine growth retarded, appropriate for gestational age, or large for gestational age infants alone.

  5. Heparin/heparan sulfates bind to and modulate neuronal L-type (Cav1.2) voltage-dependent Ca2+ channels

    DEFF Research Database (Denmark)

    Garau, Gianpiero; Magotti, Paola; Heine, Martin

    2015-01-01

    Our previous studies revealed that L-type voltage-dependent Ca2+ channels (Cav1.2 L-VDCCs) are modulated by the neural extracellular matrix backbone, polyanionic glycan hyaluronic acid. Here we used isothermal titration calorimetry and screened a set of peptides derived from the extracellular......M), integrating their enthalpic and entropic binding contributions. Interaction between heparin and recombinant as well as native full-length neuronal Cav1.2α1 channels was confirmed using the heparin–agarose pull down assay. Whole cell patch clamp recordings in HEK293 cells transfected with neuronal Cav1.......2 channels revealed that enzymatic digestion of highly sulfated heparan sulfates with heparinase 1 affects neither voltage-dependence of channel activation nor the level of steady state inactivation, but did speed up channel inactivation. Treatment of hippocampal cultures with heparinase 1 reduced the firing...

  6. Analyses of Interactions Between Heparin and the Apical Surface Proteins of Plasmodium falciparum

    Science.gov (United States)

    Kobayashi, Kyousuke; Takano, Ryo; Takemae, Hitoshi; Sugi, Tatsuki; Ishiwa, Akiko; Gong, Haiyan; Recuenco, Frances C.; Iwanaga, Tatsuya; Horimoto, Taisuke; Akashi, Hiroomi; Kato, Kentaro

    2013-11-01

    Heparin, a sulfated glycoconjugate, reportedly inhibits the blood-stage growth of the malaria parasite Plasmodium falciparum. Elucidation of the inhibitory mechanism is valuable for developing novel invasion-blocking treatments based on heparin. Merozoite surface protein 1 has been reported as a candidate target of heparin; however, to better understand the molecular mechanisms involved, we characterized the molecules that bind to heparin during merozoite invasion. Here, we show that heparin binds only at the apical tip of the merozoite surface and that multiple heparin-binding proteins localize preferentially in the apical organelles. To identify heparin-binding proteins, parasite proteins were fractionated by means of heparin affinity chromatography and subjected to immunoblot analysis with ligand-specific antibodies. All tested members of the Duffy and reticulocyte binding-like families bound to heparin with diverse affinities. These findings suggest that heparin masks the apical surface of merozoites and blocks interaction with the erythrocyte membrane after initial attachment.

  7. Inhibition of iodine-125-labeled human follitropin binding to testicular receptor by epidermal growth factor and synthetic peptides

    International Nuclear Information System (INIS)

    Sluss, P.M.; Krystek, S.R. Jr.; Andersen, T.T.; Melson, B.E.; Huston, J.S.; Ridge, R.; Reichert, L.E. Jr.

    1986-01-01

    Two tetrapeptide sequence homologies between mouse epidermal growth factor precursor (mEGFP) and human follitropin (FSH) were revealed by a computer program that identifies identical residues among polypeptide sequences. The two tetrapeptides, Lys-Thr-Cys-Thr (KTCT) and Thr-Arg-Asp-Leu (TRDL), are present in the hormone-specific beta subunit of FSH from all species studied. These tetrapeptides are not present in the alpha subunit, which is common to all pituitary glycoprotein hormones. Both tetrapeptides are also found in mEGFP, and one tetrapeptide, TRDL, is located within the 53-residue form of mEGF purified from mouse submaxillary glands. Computer-generated hydropathy profiles predicted that both tetrapeptides are located in hydrophilic portions of the FSH beta subunit and that TRDL is in a hydrophilic portion of commercially available mEGF. Therefore, the tetrapeptides might be accessible to receptor binding sites for FSH. We report that mEGF inhibits binding of 125 I-labeled human FSH to receptors in testis by 50% (I50) at a concentration of 1.8 X 10(-5) M. No binding inhibition was observed by GnRH or arginine-vasopressin at 10(-4) M, neither of which contain the tetrapeptide sequences. FSH beta subunit, which contains both tetrapeptides, also inhibited binding (I50 = 9 X 10(-8) M) of 125 I-labeled human FSH to testis receptor. Thus, it appears that FSH beta subunit and mEGF are capable of inhibiting binding of FSH to testicular FSH receptors, presumably through interactions that include the homologous tetrapeptides. This presumption was supported by the observation that the synthetic tetrapeptides (KTCT or TRDL) were also active in inhibiting binding of 125 I-labeled human FSH to testis receptor

  8. Direct astatination of a tumour-binding protein, human epidermal growth factor, using nido-carborane as a prosthetic group

    International Nuclear Information System (INIS)

    Sjoestroem, A.; Carlsson, J.; Lundqvist, H.; Koziorowski, J.

    2003-01-01

    A method for direct astatine labeling of proteins has been investigated. Binding sites for astatine were created by coupling of a nido-carborane derivative to a protein, the human epidermal growth factor (hEGF), using two different conjugation methods - by glutaraldehyde cross-linking or by introduction of sulfohydryl groups by Traut's reagent with subsequent linking of ANC-1 with m-maleimidobenzoyl-N-hydroxysulfosuccinimide ester. The conjugates were astatinated using the Chloramine-T method in high yield. The best labeling was obtained by the glutaraldehyde conjugate with an average yield of 68 ± 9%. In vitro stability tests indicated that the glutaraldehyde conjugated label was as stable as hEGF labeled with astatobenzoate. (author)

  9. Construction of multifunctional proteins for tissue engineering: epidermal growth factor with collagen binding and cell adhesive activities.

    Science.gov (United States)

    Hannachi Imen, Elloumi; Nakamura, Makiko; Mie, Masayasu; Kobatake, Eiry

    2009-01-01

    The development of different techniques based on natural and polymeric scaffolds are useful for the design of different biomimetic materials. These approaches, however, require supplementary steps for the chemical or physical modification of the biomaterial. To avoid such steps, in the present study, we constructed a new multifunctional protein that can be easily immobilized onto hydrophobic surfaces, and at the same time helps enhance specific cell adhesion and proliferation onto collagen substrates. A collagen binding domain was fused to a previously constructed protein, which had an epidermal growth factor fused to a hydrophobic peptide that allows for cell adhesion. The new fusion protein, designated fnCBD-ERE-EGF is produced in Escherichia coli, and its abilities to bind to collagen and promote cell proliferation were investigated. fnCBD-ERE-EGF was shown to keep both collagen binding and cell growth-promoting activities comparable to those of the corresponding unfused proteins. The results obtained in this study also suggest the use of a fnCBD-ERE-EGF as an alternative for the design of multifunctional ECM-bound growth factor based materials.

  10. Targeting hepatic heparin-binding EGF-like growth factor (HB-EGF) induces anti-hyperlipidemia leading to reduction of angiotensin II-induced aneurysm development.

    Science.gov (United States)

    Kim, Seonwook; Yang, Lihua; Kim, Seongu; Lee, Richard G; Graham, Mark J; Berliner, Judith A; Lusis, Aldons J; Cai, Lei; Temel, Ryan E; Rateri, Debra L; Lee, Sangderk

    2017-01-01

    The upregulated expression of heparin binding EGF-like growth factor (HB-EGF) in the vessel and circulation is associated with risk of cardiovascular disease. In this study, we tested the effects of HB-EGF targeting using HB-EGF-specific antisense oligonucleotide (ASO) on the development of aortic aneurysm in a mouse aneurysm model. Low-density lipoprotein receptor (LDLR) deficient mice (male, 16 weeks of age) were injected with control and HB-EGF ASOs for 10 weeks. To induce aneurysm, the mice were fed a high fat diet (22% fat, 0.2% cholesterol; w/w) at 5 week point of ASO administration and infused with angiotensin II (AngII, 1,000ng/kg/min) for the last 4 weeks of ASO administration. We confirmed that the HB-EGF ASO administration significantly downregulated HB-EGF expression in multiple tissues including the liver. Importantly, the HB-EGF ASO administration significantly suppressed development of aortic aneurysms including thoracic and abdominal types. Interestingly, the HB-EGF ASO administration induced a remarkable anti-hyperlipidemic effect by suppressing very low density lipoprotein (VLDL) level in the blood. Mechanistically, the HB-EGF targeting suppressed hepatic VLDL secretion rate without changing heparin-releasable plasma triglyceride (TG) hydrolytic activity or fecal neutral cholesterol excretion rate. This result suggested that the HB-EGF targeting induced protection against aneurysm development through anti-hyperlipidemic effects. Suppression of hepatic VLDL production process appears to be a key mechanism for the anti-hyperlipidemic effects by the HB-EGF targeting.

  11. M/sub r/ 25,000 heparin-binding protein from guinea pig brain is a high molecular weight form of basic fibroblast growth factor

    International Nuclear Information System (INIS)

    Moscatelli, D.; Joseph-Silverstein, J.; Manejias, R.; Rifkin, D.B.

    1987-01-01

    A M/sub r/ 25,000 form of basic fibroblast growth factor (bFGF) has been isolated from guinea pig grain along with the typical M/sub r/ 18,000 form. Both forms were purified to homogeneity by a combination of heparin-affinity chromatography and ion-exchange chromatography on an FPLC Mono S column. The M/sub r/ 25,000 form, like the M/sub r/ 18,000 form was not eluted from the heparin-affinity column with 0.95 M NaCl, but was eluted with 2 M NaCl. The M/sub r/ 25,000 guinea pig protein stimulated plasminogen activator production by cultured bovine capillary endothelial cells in a dose-dependent manner at concentration of 0.1-10 ngml, the same range that was effective for guinea pig and human M/sub r/ 18,000 bFGFs. The binding of human 125 I-labeled bFGF to baby hamster kidney cells is inhibited equally by the M/sub r/ 25,000 guinea pig protein and the M/sub r/ 18,000 guinea pig and human bFGFs. Polyclonal antibodies raised against human bFGF recognize both the M/sub r/ 25,000 and 18,000 guinea pig proteins in an immunoblot analysis. In a radioimmunoassay, both the M/sub r/ 25,000 and M/sub r/ 18,000 guinea pig proteins compete equally well with iodinated human bFGF for binding to the anti-human bFGF antibodies. When treated with low concentrations of trypsin, the M/sub r/ 25,000 guinea pig bFGF was converted to a M/sub r/ 18,000 protein. These results show that the two molecules are closely related and suggest that the M/sub r/ 25,000 protein shares substantial homology with the M/sub r/ 18,000 bFGF

  12. Prevention of adverse events of interferon γ gene therapy by gene delivery of interferon γ-heparin-binding domain fusion protein in mice

    Directory of Open Access Journals (Sweden)

    Mitsuru Ando

    2014-01-01

    Full Text Available Sustained gene delivery of interferon (IFN γ can be an effective treatment, but our previous study showed high levels of IFNγ-induced adverse events, including the loss of body weight. These unwanted events could be reduced by target-specific delivery of IFNγ after in vivo gene transfer. To achieve this, we selected the heparin-binding domain (HBD of extracellular superoxide dismutase as a molecule to anchor IFNγ to the cell surface. We designed three IFNγ derivatives, IFNγ-HBD1, IFNγ-HBD2, and IFNγ-HBD3, each of which had 1, 2, or 3 HBDs, respectively. Each plasmid-encoding fusion proteins was delivered to the liver, a model target in this study, by hydrodynamic tail vein injection. The serum concentration of IFNγ-HBD2 and IFNγ-HBD3 after gene delivery was lower than that of IFNγ or IFNγ-HBD1. Gene delivery of IFNγ-HBD2, but not of IFNγ-HBD3, effectively increased the mRNA expression of IFNγ-inducible genes in the liver, suggesting liver-specific distribution of IFNγ-HBD2. Gene delivery of IFNγ-HBD2-suppressed tumor growth in the liver as efficiently as that of IFNγ with much less symptoms of adverse effects. These results indicate that the adverse events of IFNγ gene transfer can be prevented by gene delivery of IFNγ-HBD2, a fusion protein with high cell surface affinity.

  13. Human trophoblast survival at low oxygen concentrations requires metalloproteinase-mediated shedding of heparin-binding EGF-like growth factor.

    Science.gov (United States)

    Armant, D Randall; Kilburn, Brian A; Petkova, Anelia; Edwin, Samuel S; Duniec-Dmuchowski, Zophia M; Edwards, Holly J; Romero, Roberto; Leach, Richard E

    2006-02-01

    Heparin-binding EGF-like growth factor (HBEGF), which is expressed in the placenta during normal pregnancy, is down regulated in pre-eclampsia, a human pregnancy disorder associated with poor trophoblast differentiation and survival. This growth factor protects against apoptosis during stress, suggesting a role in trophoblast survival in the relatively low O(2) ( approximately 2%) environment of the first trimester conceptus. Using a well-characterized human first trimester cytotrophoblast cell line, we found that a 4-hour exposure to 2% O(2) upregulates HBEGF synthesis and secretion independently of an increase in its mRNA. Five other expressed members of the EGF family are largely unaffected. At 2% O(2), signaling via HER1 or HER4, known HBEGF receptors, is required for both HBEGF upregulation and protection against apoptosis. This positive-feedback loop is dependent on metalloproteinase-mediated cleavage and shedding of the HBEGF ectodomain. The restoration of trophoblast survival by the addition of soluble HBEGF in cultures exposed to low O(2) and metalloproteinase inhibitor suggests that the effects of HBEGF are mediated by autocrine/paracrine, rather than juxtacrine, signaling. Our results provide evidence that a post-transcriptional mechanism induced in trophoblasts by low O(2) rapidly amplifies HBEGF signaling to inhibit apoptosis. These findings have a high clinical significance, as the downregulation of HBEGF in pre-eclampsia is likely to be a contributing factor leading to the demise of trophoblasts.

  14. Enhanced effect of BCG vaccine against pulmonary Mycobacterium tuberculosis infection in mice with lung Th17 response to mycobacterial heparin-binding hemagglutinin adhesin antigen.

    Science.gov (United States)

    Fukui, Masayuki; Shinjo, Kikuko; Umemura, Masayuki; Shigeno, Satoko; Harakuni, Tetsuya; Arakawa, Takeshi; Matsuzaki, Goro

    2015-12-01

    Although the BCG vaccine can prevent tuberculosis (TB) in infants, its ability to prevent adult pulmonary TB is reportedly limited. Therefore, development of a novel effective vaccine against pulmonary TB has become an international research priority. We have previously reported that intranasal vaccination of mice with a mycobacterial heparin-binding hemagglutinin adhesin (HBHA) plus mucosal adjuvant cholera toxin (CT) enhances production of IFN-γ and anti-HBHA antibody and suppresses extrapulmonary bacterial dissemination after intranasal infection with BCG. In the present study, the effects of intranasal HBHA + CT vaccine on murine pulmonary Mycobacterium tuberculosis (Mtb) infection were examined. Intranasal HBHA + CT vaccination alone failed to reduce the bacterial burden in the infected lung. However, a combination vaccine consisting of s.c. BCG priming and an intranasal HBHA + CT booster significantly enhanced protective immunity against pulmonary Mtb infection on day 14 compared with BCG vaccine alone. Further, it was found that intranasal HBHA + CT vaccine enhanced not only IFN-γ but also IL-17A production by HBHA-specific T cells in the lung after pulmonary Mtb infection. Therefore, this combination vaccine may be a good candidate for a new vaccine strategy against pulmonary TB. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

  15. Structural characterization of pharmaceutical heparins prepared from different animal tissues.

    Science.gov (United States)

    Fu, Li; Li, Guoyun; Yang, Bo; Onishi, Akihiro; Li, Lingyun; Sun, Peilong; Zhang, Fuming; Linhardt, Robert J

    2013-05-01

    Although most pharmaceutical heparin used today is obtained from porcine intestine, heparin has historically been prepared from bovine lung and ovine intestine. There is some regulatory concern about establishing the species origin of heparin. This concern began with the outbreak of mad cow disease in the 1990s and was exacerbated during the heparin shortage in the 2000s and the heparin contamination crisis of 2007-2008. Three heparins from porcine, ovine, and bovine were characterized through state-of-the-art carbohydrate analysis methods with a view profiling their physicochemical properties. Differences in molecular weight, monosaccharide and disaccharide composition, oligosaccharide sequence, and antithrombin III-binding affinity were observed. These data provide some insight into the variability of heparins obtained from these three species and suggest some analytical approaches that may be useful in confirming the species origin of a heparin active pharmaceutical ingredient. Copyright © 2013 Wiley Periodicals, Inc.

  16. Quantitative description of thermodynamic and kinetic properties of the platelet factor 4/heparin bonds

    Science.gov (United States)

    Nguyen, Thi-Huong; Greinacher, Andreas; Delcea, Mihaela

    2015-05-01

    Heparin is the most important antithrombotic drug in hospitals. It binds to the endogenous tetrameric protein platelet factor 4 (PF4) forming PF4/heparin complexes which may cause a severe immune-mediated adverse drug reaction, so-called heparin-induced thrombocytopenia (HIT). Although new heparin drugs have been synthesized to reduce such a risk, detailed bond dynamics of the PF4/heparin complexes have not been clearly understood. In this study, single molecule force spectroscopy (SMFS) is utilized to characterize the interaction of PF4 with heparins of defined length (5-, 6-, 8-, 12-, and 16-mers). Analysis of the force-distance curves shows that PF4/heparin binding strength rises with increasing heparin length. In addition, two binding pathways in the PF4/short heparins (=8-mers) are identified. We provide a model for the PF4/heparin complexes in which short heparins bind to one PF4 tetramer, while long heparins bind to two PF4 tetramers. We propose that the interaction between long heparins and PF4s is not only due to charge differences as generally assumed, but also due to hydrophobic interaction between two PF4s which are brought close to each other by long heparin. This complicated interaction induces PF4/heparin complexes more stable than other ligand-receptor interactions. Our results also reveal that the boundary between antigenic and non-antigenic heparins is between 8- and 12-mers. These observations are particularly important to understand processes in which PF4-heparin interactions are involved and to develop new heparin-derived drugs.Heparin is the most important antithrombotic drug in hospitals. It binds to the endogenous tetrameric protein platelet factor 4 (PF4) forming PF4/heparin complexes which may cause a severe immune-mediated adverse drug reaction, so-called heparin-induced thrombocytopenia (HIT). Although new heparin drugs have been synthesized to reduce such a risk, detailed bond dynamics of the PF4/heparin complexes have not been clearly

  17. The acyl-CoA binding protein is required for normal epidermal barrier function in mice

    DEFF Research Database (Denmark)

    Bloksgaard, Maria; Bek, Signe; Marcher, Ann-Britt

    2012-01-01

    (+/+) and ACBP(-/-) mice showed very similar composition, except for a significant and specific decrease in the very long chain free fatty acids (VLC-FFA) in stratum corneum of ACBP(-/-) mice. This finding indicates that ACBP is critically involved in the processes that lead to production of stratum corneum VLC......The acyl-CoA binding protein (ACBP) is a 10 kDa intracellular protein expressed in all eukaryotic species. Mice with targeted disruption of Acbp (ACBP(-/-) mice) are viable and fertile but present a visible skin and fur phenotype characterized by greasy fur and development of alopecia and scaling...... with age. Morphology and development of skin and appendages are normal in ACBP(-/-) mice; however, the stratum corneum display altered biophysical properties with reduced proton activity and decreased water content. Mass spectrometry analyses of lipids from epidermis and stratum corneum of ACBP...

  18. Conditional loss of heparin-binding EGF-like growth factor results in enhanced liver fibrosis after bile duct ligation in mice

    Energy Technology Data Exchange (ETDEWEB)

    Takemura, Takayo; Yoshida, Yuichi [Department of Gastroenterology and Hepatology, Osaka University, Graduate School of Medicine, Osaka (Japan); Kiso, Shinichi, E-mail: kiso@gh.med.osaka-u.ac.jp [Department of Gastroenterology and Hepatology, Osaka University, Graduate School of Medicine, Osaka (Japan); Kizu, Takashi; Furuta, Kunimaro; Ezaki, Hisao; Hamano, Mina; Egawa, Mayumi; Chatani, Norihiro; Kamada, Yoshihiro [Department of Gastroenterology and Hepatology, Osaka University, Graduate School of Medicine, Osaka (Japan); Imai, Yasuharu [Department of Gastroenterology, Ikeda Municipal Hospital, Ikeda, Osaka (Japan); Higashiyama, Shigeki [Department of Biochemistry and Molecular Genetics, Ehime University, Graduate School of Medicine and Department of Cell Growth and Tumor Regulation, Proteo-Medicine Research Center (ProMRes), Ehime University, Shitsukawa, Toon, Ehime (Japan); Iwamoto, Ryo; Mekada, Eisuke [Department of Cell Biology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka (Japan); Takehara, Tetsuo [Department of Gastroenterology and Hepatology, Osaka University, Graduate School of Medicine, Osaka (Japan)

    2013-07-26

    Highlights: •HB-EGF expression was increased during the development of liver fibrosis. •Conditional HB-EGF knockout mouse showed enhanced experimental liver fibrosis. •HB-EGF antagonized TGF-β-induced activation of hepatic stellate cells. •We report a possible protective role of HB-EGF in cholestatic liver fibrosis. -- Abstract: Our aims were to evaluate the involvement of heparin-binding EGF-like growth factor (HB-EGF) in liver fibrogenesis of humans and mice and to elucidate the effect of HB-EGF deficiency on cholestatic liver fibrosis using conditional HB-EGF knockout (KO) mice. We first demonstrated that gene expression of HB-EGF had a positive significant correlation with that of collagen in human fibrotic livers, and was increased in bile duct ligation (BDL)-induced fibrotic livers in mouse. We then generated conditional HB-EGF knockout (KO) mice using the interferon inducible Mx-1 promoter driven Cre recombinase transgene and wild type (WT) and KO mice were subjected to BDL. After BDL, KO mice exhibited enhanced liver fibrosis with increased expression of collagen, compared with WT mice. Finally, we used mouse hepatic stellate cells (HSCs) to examine the role of HB-EGF in the activation of these cells and showed that HB-EGF antagonized TGF-β-induced gene expression of collagen in mouse primary HSCs. Interestingly, HB-EGF did not prevent the TGF-β-induced nuclear accumulation of Smad3, but did lead to stabilization of the Smad transcriptional co-repressor TG-interacting factor. In conclusion, our data suggest a possible protective role of HB-EGF in cholestatic liver fibrosis.

  19. Heparin-Binding EGF-like Growth Factor (HB-EGF) stimulates the proliferation of Müller glia-derived progenitor cells in avian and murine retinas

    Science.gov (United States)

    Todd, Levi; Volkov, Leo I.; Zelinka, Chris; Squires, Natalie; Fischer, Andy J.

    2015-01-01

    Müller glia can be stimulated to de-differentiate, proliferate and form Müller glia-derived progenitor cells (MGPCs) that regenerate retinal neurons. In the zebrafish retina, Heparin-Binding EGF-like Growth Factor (HB-EGF) may be one of the key factors that stimulate the formation of proliferating MGPCs. Currently nothing is known about the influence of HB-EGF on the proliferative potential of Müller glia in retinas of birds and rodents. In the chick retina, we found that levels of both hb-egf and egf-receptor are rapidly and transiently up-regulated following NMDA-induced damage. Although intraocular injections of HB-EGF failed to stimulate cell-signaling or proliferation of Müller glia in normal retinas, HB-EGF stimulated proliferation of MGPCs in damaged retinas. By comparison, inhibition of the EGF-receptor (EGFR) decreased the proliferation of MGPCs in damaged retinas. HB-EGF failed to act synergistically with FGF2 to stimulate the formation of MGPCs in the undamaged retina and inhibition of EGF-receptor did not suppress FGF2-mediated formation of MGPCs. In the mouse retina, HB-EGF stimulated the proliferation of Müller glia following NMDA-induced damage. Furthermore, HB-EGF stimulated not only MAPK-signaling in Müller glia/MGPCs, but also activated mTor- and Jak/Stat-signaling. We propose that levels of expression of EGFR are rate-limiting to the responses of Müller glia to HB-EGF and the expression of EGFR can be induced by retinal damage, but not by FGF2-treatment. We conclude that HB-EGF is mitogenic to Müller glia in both chick and mouse retinas, and HB-EGF is an important player in the formation of MGPCs in damaged retinas. PMID:26500021

  20. Conditional loss of heparin-binding EGF-like growth factor results in enhanced liver fibrosis after bile duct ligation in mice

    International Nuclear Information System (INIS)

    Takemura, Takayo; Yoshida, Yuichi; Kiso, Shinichi; Kizu, Takashi; Furuta, Kunimaro; Ezaki, Hisao; Hamano, Mina; Egawa, Mayumi; Chatani, Norihiro; Kamada, Yoshihiro; Imai, Yasuharu; Higashiyama, Shigeki; Iwamoto, Ryo; Mekada, Eisuke; Takehara, Tetsuo

    2013-01-01

    Highlights: •HB-EGF expression was increased during the development of liver fibrosis. •Conditional HB-EGF knockout mouse showed enhanced experimental liver fibrosis. •HB-EGF antagonized TGF-β-induced activation of hepatic stellate cells. •We report a possible protective role of HB-EGF in cholestatic liver fibrosis. -- Abstract: Our aims were to evaluate the involvement of heparin-binding EGF-like growth factor (HB-EGF) in liver fibrogenesis of humans and mice and to elucidate the effect of HB-EGF deficiency on cholestatic liver fibrosis using conditional HB-EGF knockout (KO) mice. We first demonstrated that gene expression of HB-EGF had a positive significant correlation with that of collagen in human fibrotic livers, and was increased in bile duct ligation (BDL)-induced fibrotic livers in mouse. We then generated conditional HB-EGF knockout (KO) mice using the interferon inducible Mx-1 promoter driven Cre recombinase transgene and wild type (WT) and KO mice were subjected to BDL. After BDL, KO mice exhibited enhanced liver fibrosis with increased expression of collagen, compared with WT mice. Finally, we used mouse hepatic stellate cells (HSCs) to examine the role of HB-EGF in the activation of these cells and showed that HB-EGF antagonized TGF-β-induced gene expression of collagen in mouse primary HSCs. Interestingly, HB-EGF did not prevent the TGF-β-induced nuclear accumulation of Smad3, but did lead to stabilization of the Smad transcriptional co-repressor TG-interacting factor. In conclusion, our data suggest a possible protective role of HB-EGF in cholestatic liver fibrosis

  1. Nuclear androgen receptors in human prostatic tissue. Extraction with heparin and estimation of the number of binding sites with different methods

    International Nuclear Information System (INIS)

    Foekens, J.A.; Bolt-de Vries, J.; Mulder, E.; Blankenstein, M.A.; Schroeder, F.H.; Molen, H.J. van der

    1981-01-01

    A procedure for the estimation of nuclear androgen receptors in benign prostatic hyperplastic tissue is described, which employs extraction of receptors from nuclei with buffers containing heparin. Extraction of a nuclear pellet with a heparin-containing (1 g/l) buffer appeared to have definite advantages over 0.4 mol/l KCl extraction. Heparin appeared to be twice as efficient in extracting androgen receptors. In addition aggregated receptor proteins, formed after storage at -80 0 C, were partly deaggregated by heparin. Specific isolation of the androgen receptor was performed using either agar gel electrophoresis, protamine sulphate precipitation or LH-20 gel filtration. A comparison was made between the amounts of estimated receptors with these different techniques. Protamine sulphate precipitation resulted in the highest estimates of receptor-bound 5α-[ 3 H]dihydrotestosterone ( 3 H-DHT). Treatment of the labelled nuclear extracts with a charcoal suspension prior to the receptor assay resulted in lower amounts of estimated androgen receptors. A method for routine evaluation of nuclear androgen receptors in prostatic tissue has been evaluated, which involves extraction of nuclear pellets with a heparin-containing (1 g/l) buffer, exchange labelling of the nuclear extracts for 20 h at 10 0 C and quantification of the receptors with protamine sulphate precipitation. (Auth.)

  2. Mr 25,000 heparin-binding protein from guinea pig brain is a high molecular weight form of basic fibroblast growth factor.

    OpenAIRE

    Moscatelli, D; Joseph-Silverstein, J; Manejias, R; Rifkin, D B

    1987-01-01

    A Mr 25,000 form of basic fibroblast growth factor (bFGF) has been isolated from guinea pig brain along with the typical Mr 18,000 form. Both forms were purified to homogeneity by a combination of heparin-affinity chromatography and ion-exchange chromatography on an FPLC Mono S column. The Mr 25,000 form, like the Mr 18,000 form, was not eluted from the heparin-affinity column with 0.95 M NaCl, but was eluted with 2 M NaCl. The Mr 25,000 guinea pig protein stimulated plasminogen activator pro...

  3. Circulating chromatin-anti-chromatin antibody complexes bind with high affinity to dermo-epidermal structures in murine and human lupus nephritis

    DEFF Research Database (Denmark)

    Fismen, S; Hedberg, A; Fenton, K A

    2009-01-01

    Murine and human lupus nephritis are characterized by glomerular deposits of electron-dense structures (EDS). Dominant components of EDS are chromatin fragments and IgG antibodies. Whether glomerular EDS predispose for similar deposits in skin is unknown. We analysed (i) whether dermo-epidermal i......Murine and human lupus nephritis are characterized by glomerular deposits of electron-dense structures (EDS). Dominant components of EDS are chromatin fragments and IgG antibodies. Whether glomerular EDS predispose for similar deposits in skin is unknown. We analysed (i) whether dermo......-epidermal immune complex deposits have similar molecular composition as glomerular deposits, (ii) whether chromatin fragments bind dermo-epidermal structures, and (iii) whether deposits in nephritic glomeruli predispose for accumulation of similar deposits in skin. Paired skin and kidney biopsies from nephritic...... (NZBxNZW)F1 and MRL-lpr/lpr mice and from five patients with lupus nephritis were analysed by immunofluorescence, immune electron microscopy (IEM) and co-localization TUNEL IEM. Affinity of chromatin fragments for membrane structures was determined by surface plasmon resonance. Results demonstrated (i...

  4. A spectroscopic study of interaction of cationic dyes with heparin

    Directory of Open Access Journals (Sweden)

    R. Nandini

    2010-01-01

    Full Text Available The interaction of two cationic dyes namely, acridine orange and pinacyanol chloride with an anionic polyelectrolyte, heparin, has been investigated by spectrophotometric method.The polymer induced metachromasy in the dyes resulting in the shift of the absorption maxima of the dyes towards shorter wavelengths. The stability of the complexes formed between acridine orange and heparin was found to be lesser than that formed between pinacyanol chloride and heparin. This fact was further confirmed by reversal studies using alcohols, urea and surfactants. The interaction of acridine orange with heparin has also been investigated fluorimetrically.The interaction parameters revealed that binding between acridine orange and heparin arises due to electrostatic interaction while that between pinacyanol chloride and heparin is found to involve both electrostatic and hydrophobic forces. The effect of the structure of the dye in inducing metachromasy has also been discussed.

  5. Heparin and heparin-induced thrombocytopenia

    African Journals Online (AJOL)

    2007-06-15

    Jun 15, 2007 ... Heparin is one of the most widely used drugs. It is used routinely for treatment and thromboprophylaxis in a broad spectrum of conditions including venous thromboembolism, atrial fibrillation, acute coronary syndromes, peripheral vascular disease and to maintain the patency of indwelling catheters and ...

  6. Heparin pharmacovigilance in Brazil.

    Science.gov (United States)

    Junqueira, Daniela Rezende Garcia; Viana, Thércia Guedes; Peixoto, Eliane R de M; Barros, Fabiana C R de; Carvalho, Maria das Graças; Perini, Edson

    2011-01-01

    To investigate the biological origin of injectable unfractioned heparin available in Brazilian market by discussing the impact of the profile of commercial products and the changes in heparin monograph on the drug safety. The Anvisa data base for the Registered Products of Pharmaceutical Companies and the Dictionary of Pharmaceutical Specialties (DEF 2008/2009) were searched. A survey with industries having an active permission for marketing the drug in Brazil was conducted. Five companies were granted a permission to market unfractioned heparin in Brazil. Three of them are porcine in origin and two of them are bovine in origin, with only one explicitly showing this information in the package insert. The effectiveness and safety of heparin studied in non-Brazilian populations may not represent the Brazilian reality, since most countries no longer produce bovine heparin. The currently marketed heparin has approximately 10% less anticoagulant activity than that previously produced and this change may have clinical implications. Evidence about the lack of dose interchangeability between bovine and porcine heparins and the unique safety profile of these drugs indicates the need to follow the treatment and the patients' response. Events threatening the patient's safety must be reported to the pharmacovigilance system in each particular country.

  7. Heparin: The Silver Bullet of Aneurysmal Subarachnoid Hemorrhage?

    Directory of Open Access Journals (Sweden)

    Nicolas K. Khattar

    2018-03-01

    Full Text Available Various neurological diseases have recently been associated with neuroinflammation and worsening outcomes. Subarachnoid hemorrhage has been shown to generate a potent neuroinflammatory response. Heparin is a potential effective anti-inflammatory agent to prevent initial injury as well as delayed neurological decline. Different mechanisms of action for heparin have been proposed including, but not limited to the binding and neutralization of oxyhemoglobin, decreased transcription and signal transduction of endothelin-1, inhibition of binding to vessel wall selectins and vascular leakage into the subarachnoid space as well as direct binding and neutralization of inflammatory molecules. With a reasonably safe side-effect profile, heparin has shown significant promise in small series in human studies of aneurysmal subarachnoid hemorrhage in decreasing both initial and delayed neurological injury. Further studies are needed to validate various neuroprotective features of heparin in subarachnoid hemorrhage as well as other disease states.

  8. Heparin-Induced Thrombocytopenia

    Science.gov (United States)

    ... HIT information card. Early identification of HIT and avoidance of inappropriate heparin therapy can help promote a ... Heart Association is a qualified 501(c)(3) tax-exempt organization. *Red Dress™ DHHS, Go Red™ AHA; ...

  9. Involvement of three meningococcal surface-exposed proteins, the heparin-binding protein NhbA, the α-peptide of IgA protease and the autotransporter protease NalP, in initiation of biofilm formation

    KAUST Repository

    Arenas, Jesú s; Nijland, Reindert; Rodriguez, Francisco J.; Bosma, Tom N. P.; Tommassen, Jan

    2012-01-01

    Neisseria meningitidis is a common and usually harmless inhabitant of the mucosa of the human nasopharynx, which, in rare cases, can cross the epithelial barrier and cause meningitis and sepsis. Biofilm formation favours the colonization of the host and the subsequent carrier state. Two different strategies of biofilm formation, either dependent or independent on extracellular DNA (eDNA), have been described for meningococcal strains. Here, we demonstrate that the autotransporter protease NalP, the expression of which is phase variable, affects eDNA-dependent biofilm formation in N.meningitidis. The effect of NalP was found in biofilm formation under static and flow conditions and was dependent on its protease activity. Cleavage of the heparin-binding antigen NhbA and the α-peptide of IgA protease, resulting in the release of positively charged polypeptides from the cell surface, was responsible for the reduction in biofilm formation when NalP is expressed. Both NhbA and the α-peptide of IgA protease were shown to bind DNA. We conclude that NhbA and the α-peptide of IgA protease are implicated in biofilm formation by binding eDNA and that NalP is an important regulator of this process through the proteolysis of these surface-exposed proteins. © 2012 Blackwell Publishing Ltd.

  10. Involvement of three meningococcal surface-exposed proteins, the heparin-binding protein NhbA, the α-peptide of IgA protease and the autotransporter protease NalP, in initiation of biofilm formation

    KAUST Repository

    Arenas, Jesús

    2012-12-04

    Neisseria meningitidis is a common and usually harmless inhabitant of the mucosa of the human nasopharynx, which, in rare cases, can cross the epithelial barrier and cause meningitis and sepsis. Biofilm formation favours the colonization of the host and the subsequent carrier state. Two different strategies of biofilm formation, either dependent or independent on extracellular DNA (eDNA), have been described for meningococcal strains. Here, we demonstrate that the autotransporter protease NalP, the expression of which is phase variable, affects eDNA-dependent biofilm formation in N.meningitidis. The effect of NalP was found in biofilm formation under static and flow conditions and was dependent on its protease activity. Cleavage of the heparin-binding antigen NhbA and the α-peptide of IgA protease, resulting in the release of positively charged polypeptides from the cell surface, was responsible for the reduction in biofilm formation when NalP is expressed. Both NhbA and the α-peptide of IgA protease were shown to bind DNA. We conclude that NhbA and the α-peptide of IgA protease are implicated in biofilm formation by binding eDNA and that NalP is an important regulator of this process through the proteolysis of these surface-exposed proteins. © 2012 Blackwell Publishing Ltd.

  11. Severe heparin osteoporosis in pregnancy.

    OpenAIRE

    Griffiths, H. T.; Liu, D. T.

    1984-01-01

    A case of severe osteoporosis following administration of low dose subcutaneous heparin in pregnancy is reported. Possible reasons for the condition are suggested which caution against the indiscriminate use of subcutaneous heparin in pregnancy.

  12. Increased expression of heparin binding EGF (HB-EGF), amphiregulin, TGF alpha and epiregulin in androgen-independent prostate cancer cell lines.

    DEFF Research Database (Denmark)

    Tørring, Niels; Sørensen, Boe Sandahl; Nexø, Ebba

    2000-01-01

    BACKGROUND: The proliferation of androgen-independent prostate cancer cell lines has previously been shown to be influenced by an autocrine loop of the epidermal growth factor (EGF) system. This observation has alerted us to study the expression of ligands and receptors from the EGF......-system in prostate cell lines. METHODS: The expression of the EGF system was determined by quantitative RT-PCR and ELISA in the normal prostate epithelial cell line (PNT1A), in the androgen sensitive-(LNCaP), and the androgen-independent (DU145 and PC3) prostate cancer cell lines. RESULTS: The expression of m...... which exhibit low expression of HER1. Similar results were obtained by ELISA. CONCLUSIONS: The data indicates a selective up-regulation of a subclass of ligands of the EGF-system in androgen-independent prostate cancer cell lines. We suggest this could be a mechanism to escape androgen dependence...

  13. Heparin for assisted reproduction.

    Science.gov (United States)

    Akhtar, Muhammad A; Sur, Shyamaly; Raine-Fenning, Nick; Jayaprakasan, Kannamannadiar; Thornton, Jim G; Quenby, Siobhan

    2013-08-17

    Heparin as an adjunct in assisted reproduction (peri-implantation heparin) is given at or after egg collection or at embryo transfer during assisted reproduction. Heparin has been advocated to improve embryo implantation and clinical outcomes.  It has been proposed that heparin enhances the intra-uterine environment by improving decidualisation with an associated activation of growth factors and a cytokine expression profile in the endometrium that is favourable to pregnancy. To investigate whether the administration of heparin around the time of implantation (peri-implantation heparin) improves clinical outcomes in subfertile women undergoing assisted reproduction. A comprehensive and exhaustive search strategy was developed in consultation with the Trials Search Co-ordinator of the Cochrane Menstrual Disorders and Subfertility Group (MDSG). The strategy was used in an attempt to identify all relevant studies regardless of language or publication status (published, unpublished, in press, and in progress). Relevant trials were identified from both electronic databases and other resources (last search 6 May 2013). All randomised controlled trials (RCTs) were included where peri-implantation heparin was given during assisted reproduction. Peri-implantation low molecular weight heparin (LMWH) during IVF/ICSI was given at or after egg collection or at embryo transfer in the included studies. Live birth rate was the primary outcome. Two review authors independently assessed the eligibility and quality of trials and extracted relevant data. The quality of the evidence was evaluated using GRADE methods. Three RCTs (involving 386 women) were included in the review.Peri-implantation LMWH administration during assisted reproduction was associated with a significant improvement in live birth rate compared with placebo or no LMWH (odds ratio (OR) 1.77, 95% confidence interval (CI) 1.07 to 2.90, three studies, 386 women, I(2) = 51%, very low quality evidence with high

  14. Profiling Heparin-Chemokine Interactions Using Synthetic Tools

    Science.gov (United States)

    de Paz, Jose L.; Moseman, E. Ashley; Noti, Christian; Polito, Laura; von Andrian, Ulrich H.; Seeberger, Peter H.

    2009-01-01

    Glycosaminoglycans (GAGs), such as heparin or heparan sulfate, are required for the in vivo function of chemokines. Chemokines play a crucial role in the recruitment of leukocyte subsets to sites of inflammation and lymphocytes trafficking. GAG-chemokine interactions mediate cell migration and determine which leukocyte subsets enter tissues. Identifying the exact GAC sequences that bind to particular chemokines is key to understand chemokine function at the molecular level and develop strategies to interfere with chemokine-mediated processes. Here, we characterize the heparin binding profiles of eight chemokines (CCL21, IL-8, CXCL12, CXCL13, CCL19, CCL25, CCL28, and CXCL16) by employing heparin microarrays containing a small library of synthetic heparin oligosaccharides. The chemokines differ significantly in their interactions with heparin oligosaccharides: While some chemokines, (e.g., CCL21) strongly bind to a hexasaccharide containing the GlcNSO3(6-OSO3)-IdoA(2-OSO3) repeating unit, CCL19 does not bind and CXCL12 binds only weakly. The carbohydrate microarray binding results were validated by surface plasmon resonance experiments. In vitro chemotaxis assays revealed that dendrimers coated with the fully sulfated heparin hexasaccharide inhibit lymphocyte migration toward CCL21. Migration toward CXCL12 or CCL19 was not affected. These in vitro homing assays indicate that multivalent synthetic heparin dendrimers inhibit the migration of lymphocytes toward certain chemokine gradients by blocking the formation of a chemokine concentration gradient on GAG endothelial chains. These findings are in agreement with preliminary in vivo measurements of circulating lymphocytes. The results presented here contribute to the understanding of GAG-chemokine interactions, a first step toward the design of novel drugs that modulate chemokine activity. PMID:18030990

  15. Investigation of Monnose-Binding Lectin gene Polymorphism in Patients with Erythema Multiforme, Stevens-Johnson Syndrome and Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis Overlap Syndrome

    Directory of Open Access Journals (Sweden)

    Sevil Toka

    2012-09-01

    Full Text Available Objective: Monnose-Binding lectin (MBL appears to play an important role in the immune system. The genetic polymorphisms in the MBL2 gene can result in a reduction of serum levels, leading to a predisposition to recurrent infection. The aim of this study is to investigate the influence of a polymorphism in codon 54 of the MBL2 gene on the susceptibility to Erythema Multiforme, Stevens-Johnson Syndrome and Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis Overlap Syndrome (EM, SJS and SJS/TEN overlap syndrome. Material and Methods: Our study included 64 patients who were clinically and/or histopathologically diagnosed with EM, SJS, and SJS/TEN overlap syndrome and 66 healthy control subjects who were genotyped for the MBL2 gene codon 54 polymorphism using the PCR-RFLP method. For all statistical analyses, the level of significance was set at p<0.05. Results: The prevalence of the B allele was 18% in the EM, SJS and SJS/TEN patient groups and 13% in the control group. No significant differences in allele frequencies of any polymorphism were observed between the patient and control groups, although the B allele was more frequent in the patient groups (p=0.328.Conclusion: Our results provide no evidence of a relationship between MBL2 gene codon 54 polymorphism and the susceptibility to EM, SJS and SJS/TEN overlap syndrome. However, these findings should be confirmed in studies with a larger sample size.

  16. N-Glycosylation of Human R-Spondin 1 Is Required for Efficient Secretion and Stability but Not for Its Heparin Binding Ability

    Directory of Open Access Journals (Sweden)

    Chiung-Fang Chang

    2016-06-01

    Full Text Available R-spondin 1 (Rspo1 plays an essential role in stem cell biology by potentiating Wnt signaling activity. Despite the fact that Rspo1 holds therapeutic potential for a number of diseases, its biogenesis is not fully elucidated. All Rspo proteins feature two amino-terminal furin-like repeats, which are responsible for Wnt signal potentiation, and a thrombospondin type 1 (TSR1 domain that can provide affinity towards heparan sulfate proteoglycans. Using chemical inhibitors, deglycosylase and site-directed mutagenesis, we found that human Rspo1 and Rspo3 are both N-glycosylated at N137, a site near the C-terminus of the furin repeat 2 domain, and Rspo2 is N-glycosylated at N160, a position near the N-terminus of TSR1 domain. Elimination of N-glycosylation at these sites affects their accumulation in media but have no effect on the ability towards heparin. Introduction of the N-glycosylation site to Rspo2 mutant at the position homologous to N137 in Rspo1 restored full glycosylation and rescued the accumulation defect of nonglycosylated Rspo2 mutant in media. Similar effect can be observed in the N137 Rspo1 or Rspo3 mutant engineered with Rspo2 N-glycosylation site. The results highlight the importance of N-glycosylation at these two positions in efficient folding and secretion of Rspo family. Finally, we further showed that human Rspo1 is subjected to endoplasmic reticulum (ER quality control in N-glycan-dependent manner. While N-glycan of Rspo1 plays a role in its intracellular stability, it had little effect on secreted Rspo1. Our findings provide evidence for the critical role of N-glycosylation in the biogenesis of Rspo1.

  17. The structure of an LIM-only protein 4 (LMO4 and Deformed epidermal autoregulatory factor-1 (DEAF1 complex reveals a common mode of binding to LMO4.

    Directory of Open Access Journals (Sweden)

    Soumya Joseph

    Full Text Available LIM-domain only protein 4 (LMO4 is a widely expressed protein with important roles in embryonic development and breast cancer. It has been reported to bind many partners, including the transcription factor Deformed epidermal autoregulatory factor-1 (DEAF1, with which LMO4 shares many biological parallels. We used yeast two-hybrid assays to show that DEAF1 binds both LIM domains of LMO4 and that DEAF1 binds the same face on LMO4 as two other LMO4-binding partners, namely LIM domain binding protein 1 (LDB1 and C-terminal binding protein interacting protein (CtIP/RBBP8. Mutagenic screening analysed by the same method, indicates that the key residues in the interaction lie in LMO4LIM2 and the N-terminal half of the LMO4-binding domain in DEAF1. We generated a stable LMO4LIM2-DEAF1 complex and determined the solution structure of that complex. Although the LMO4-binding domain from DEAF1 is intrinsically disordered, it becomes structured on binding. The structure confirms that LDB1, CtIP and DEAF1 all bind to the same face on LMO4. LMO4 appears to form a hub in protein-protein interaction networks, linking numerous pathways within cells. Competitive binding for LMO4 therefore most likely provides a level of regulation between those different pathways.

  18. Influence of heparin on radioimmunological assay of ACTH

    International Nuclear Information System (INIS)

    Dupouy, J.P.; Godaut, M.; Chatelain, A.

    1986-01-01

    1 - Heparin traps plasma ACTH, promoting the formation of aggregates with apparent high molecular weight as shown by chromatography on Sephadex G 50 fine columns. The percentage of 125 I-ACTH which appeared in the void volume of the column, increased linearly with the log. dose of heparin. 2 - Heparin at concentrations of up to 100 IU/ml does not impair ACTH adsorption on either silicic acid or Quso G 32 as well as further elution by acetic acid/acetone/water (I: 40: 59; V/V) or HCl O.I N. Silicic acid traps selectively ACTH but not heparin. 3 - Heparin interferes with direct RIA-ACTH in the plasma by decreasing 125 I-ACTH binding to the antibodies and modifying the slope of the standard curve. Unsuitable artefacts induced by heparin, as overestimation or underestimation of plasma ACTH levels by RIA, can be avoid by previous hormone extraction from heparinized plasmas. Such results emphasized the importance of the sample preparation in order to obtain consistent results [fr

  19. Heparin conjugated quantum dots for in vitro imaging applications.

    Science.gov (United States)

    Maguire, Ciaran Manus; Mahfoud, Omar Kazem; Rakovich, Tatsiana; Gerard, Valerie Anne; Prina-Mello, Adriele; Gun'ko, Yurii; Volkov, Yuri

    2014-11-01

    In this work heparin-gelatine multi-layered cadmium telluride quantum dots (QDgel/hep) were synthesised using a novel 'one-pot' method. The QDs produced were characterised using various spectroscopic and physiochemical techniques. Suitable QDs were then selected and compared to thioglycolic acid stabilised quantum dots (QDTGA) and gelatine coated quantum dots (QDgel) for utilisation in in vitro imaging experiments on live and fixed permeabilised THP-1, A549 and Caco-2 cell lines. Exposure of live THP-1 cells to QDgel/hep resulted in localisation of the QDs to the nucleus of the cells. QDgel/hep show affinity for the nuclear compartment of fixed permeabilised THP-1 and A549 cells but remain confined to cytoplasm of fixed permeabilised Caco-2 cells. It is postulated that heparin binding to the CD11b receptor facilitates the internalisation of the QDs into the nucleus of THP-1 cells. In addition, the heparin layer may reduce the unfavourable thrombogenic nature of quantum dots observed in vivo. In this study, heparin conjugated quantum dots were found to have superior imaging properties compared to its native counterparts. The authors postulate that heparin binding to the CD11b receptor facilitates QD internalization to the nucleus, and the heparin layer may reduce the in vivo thrombogenic properties of quantum dots. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. BB0347, from the lyme disease spirochete Borrelia burgdorferi, is surface exposed and interacts with the CS1 heparin-binding domain of human fibronectin.

    Directory of Open Access Journals (Sweden)

    Robert A Gaultney

    Full Text Available The causative agent of Lyme disease, Borrelia burgdorferi, codes for several known fibronectin-binding proteins. Fibronectin a common the target of diverse bacterial pathogens, and has been shown to be essential in allowing for the development of certain disease states. Another borrelial protein, BB0347, has sequence similarity with these other known fibronectin-binding proteins, and may be important in Lyme disease pathogenesis. Herein, we perform an initial characterization of BB0347 via the use of molecular and biochemical techniques. We found that BB0347 is expressed, produced, and presented on the outer surface of intact B. burgdorferi. We also demonstrate that BB0347 has the potential to be important in Lyme disease progression, and have begun to characterize the nature of the interaction between human fibronectin and this bacterial protein. Further work is needed to define the role of this protein in the borrelial infection process.

  1. Heparin: Past, Present, and Future.

    Science.gov (United States)

    Oduah, Eziafa I; Linhardt, Robert J; Sharfstein, Susan T

    2016-07-04

    Heparin, the most widely used anticoagulant drug in the world today, remains an animal-derived product with the attendant risks of adulteration and contamination. A contamination crisis in 2007-2008 increased the impetus to provide non-animal-derived sources of heparin, produced under cGMP conditions. In addition, recent studies suggest that heparin may have significant antineoplastic activity, separate and distinct from its anticoagulant activity, while other studies indicate a role for heparin in treating inflammation, infertility, and infectious disease. A variety of strategies have been proposed to produce a bioengineered heparin. In this review, we discuss several of these strategies including microbial production, mammalian cell production, and chemoenzymatic modification. We also propose strategies for creating "designer" heparins and heparan-sulfates with various biochemical and physiological properties.

  2. Targeting Heparin to Collagen within Extracellular Matrix Significantly Reduces Thrombogenicity and Improves Endothelialization of Decellularized Tissues.

    Science.gov (United States)

    Jiang, Bin; Suen, Rachel; Wertheim, Jason A; Ameer, Guillermo A

    2016-12-12

    Thrombosis within small-diameter vascular grafts limits the development of bioartificial, engineered vascular conduits, especially those derived from extracellular matrix (ECM). Here we describe an easy-to-implement strategy to chemically modify vascular ECM by covalently linking a collagen binding peptide (CBP) to heparin to form a heparin derivative (CBP-heparin) that selectively binds a subset of collagens. Modification of ECM with CBP-heparin leads to increased deposition of functional heparin (by ∼7.2-fold measured by glycosaminoglycan composition) and a corresponding reduction in platelet binding (>70%) and whole blood clotting (>80%) onto the ECM. Furthermore, addition of CBP-heparin to the ECM stabilizes long-term endothelial cell attachment to the lumen of ECM-derived vascular conduits, potentially through recruitment of heparin-binding growth factors that ultimately improve the durability of endothelialization in vitro. Overall, our findings provide a simple yet effective method to increase deposition of functional heparin on the surface of ECM-based vascular grafts and thereby minimize thrombogenicity of decellularized tissue, overcoming a significant challenge in tissue engineering of bioartificial vessels and vascularized organs.

  3. Internalization mechanisms of the epidermal growth factor receptor after activation with different ligands

    DEFF Research Database (Denmark)

    Henriksen, Lasse; Grandal, Michael Vibo; Knudsen, Stine Louise Jeppe

    2013-01-01

    after ligand activation focuses on the effect of epidermal growth factor (EGF) and transforming growth factor-α (TGF-α). For a long time it was believed that clathrin-mediated endocytosis was the major pathway for internalization of the receptor, but recent work suggests that different pathways exist....... Here we show that clathrin ablation completely inhibits internalization of EGF- and TGF-α-stimulated receptor, however the inhibition of receptor internalization in cells treated with heparin-binding EGF-like growth factor (HB-EGF) or betacellulin (BTC) was only partial. In contrast, clathrin knockdown...... fully inhibits EGFR degradation after all ligands tested. Furthermore, inhibition of dynamin function blocked EGFR internalization after stimulation with all ligands. Knocking out a number of clathrin-independent dynamin-dependent pathways of internalization had no effect on the ligand...

  4. Expression of the epidermal growth factor system in human endometrium during the menstrual cycle

    DEFF Research Database (Denmark)

    Ejskjaer, Kirsten; Sørensen, B S; Poulsen, Steen Seier

    2005-01-01

    The epidermal growth factor (EGF) system is ubiquitous in humans and plays fundamental roles in embryogenesis, development, proliferation and differentiation. As the endometrium of fertile women is characterized by proliferation and differentiation, we hypothesize a role for the EGF system....... Fourteen premenopausal women had endometrial samples removed on day 6 +/- 1 and day 6 +/- 1 and 12 +/- 1 after ovulation during one menstrual cycle. RNA was extracted and analysed by real-time PCR, and immunohistochemistry was performed to localize the components of the EGF system. Human EGF Receptor 1...... (HER1) showed highest expression during the proliferative phase, HER2 and HER4 during the early and HER3 during the late secretory phase. Amphiregulin (AR) and transforming growth factor alpha (TGFalpha) expression is highest in proliferative phase. Heparin binding (HB)-EGF and betacellulin (BCL) show...

  5. Sterilization of heparinized cuprophan hemodialysis membranes

    OpenAIRE

    ten Hoopen, Hermina W.M.; Hinrichs, W.L.J.; Hinrichs, W.L.J.; Engbers, G.H.M.; Feijen, Jan

    1996-01-01

    The effects of sterilization of dry heparinized Cuprophan hemodialysis membranes by means of ethylene oxide (EtO) exposure, gamma irradiation, or steam on the anticoagulant activity and chemical characteristics of immobilized heparin and the permeability of the membrane were investigated. Sterilization did not result in a release of heparin or heparin fragments from heparinized Cuprophan. Sterilization of heparinized Cuprophan by means of EtO exposure and gamma irradiation induced a slight, i...

  6. Hydrolysis and Sulfation Pattern Effects on Release of Bioactive Bone Morphogenetic Protein-2 from Heparin-Based Microparticles.

    Science.gov (United States)

    Tellier, Liane E; Miller, Tobias; McDevitt, Todd C; Temenoff, Johnna S

    2015-10-28

    Glycosaminoglycans (GAGs) such as heparin are promising materials for growth factor delivery due to their ability to efficiently bind positively charged growth factors including bone morphogenetic protein-2 (BMP-2) through their negatively charged sulfate groups. Therefore, the goal of this study was to examine BMP-2 release from heparin-based microparticles (MPs) after first, incorporating a hydrolytically degradable crosslinker and varying heparin content within MPs to alter MP degradation and second, altering the sulfation pattern of heparin within MPs to vary BMP-2 binding and release. Using varied MP formulations, it was found that the time course of MP degradation for 1 wt% heparin MPs was ~4 days slower than 10 wt% heparin MPs, indicating that MP degradation was dependent on heparin content. After incubating 100 ng BMP-2 with 0.1 mg MPs, most MP formulations loaded BMP-2 with ~50% efficiency and significantly more BMP-2 release (60% of loaded BMP-2) was observed from more sulfated heparin MPs (MPs with ~100% and 80% of native sulfation). Similarly, BMP-2 bioactivity in more sulfated heparin MP groups was at least four-fold higher than soluble BMP-2 and less sulfated heparin MP groups, as determined by an established C2C12 cell alkaline phosphatase (ALP) assay. Ultimately, the two most sulfated 10 wt% heparin MP formulations were able to efficiently load and release BMP-2 while enhancing BMP-2 bioactivity, making them promising candidates for future growth factor delivery applications.

  7. Collection of heparinized plasma by plasmapheresis

    NARCIS (Netherlands)

    van der Meer, P. F.; Vrielink, H.; Pietersz, R. N.; Dekker, W. J.; Reesink, H. W.

    1999-01-01

    BACKGROUND AND OBJECTIVES: Heparinized plasma can be used for exchange transfusions in neonates and is usually collected by drawing whole blood using heparin as anticoagulant. The heparinized red blood cells and buffy coat cannot be used and are therefore discarded. To collect heparinized plasma

  8. Heparin Interaction with the Primed Polymorphonuclear Leukocyte CD11b Induces Apoptosis and Prevents Cell Activation

    Directory of Open Access Journals (Sweden)

    Meital Cohen-Mazor

    2015-01-01

    Full Text Available Heparin is known to have anti-inflammatory effects, yet the mechanisms are not completely understood. In this study, we tested the hypothesis that heparin has a direct effect on activated polymorphonuclear leukocytes (PMNLs, changing their activation state, and can explain its anti-inflammatory effect. To test our hypothesis, we designed both in vitro and ex vivo studies to elucidate the mechanism by which heparin modulates PMNL functions and therefore the inflammatory response. We specifically tested the hypothesis that priming of PMNLs renders them more susceptible to heparin. Amplified levels of CD11b and increased rate of superoxide release manifested PMNL priming. Increase in cell priming resulted in a dose-dependent increase in heparin binding to PMNLs followed by augmented apoptosis. Blocking antibodies to CD11b inhibited heparin binding and abolished the apoptotic response. Moreover, heparin caused a significant dose-dependent decrease in the rate of superoxide release from PMNLs, which was blunted by blocking antibodies to CD11b. Altogether, this study shows that the interaction of heparin with the PMNL CD11b results in cell apoptosis and explains heparin’s anti-inflammatory effects.

  9. Low-molecular weight heparin increases circulating sFlt-1 levels and enhances urinary elimination.

    Directory of Open Access Journals (Sweden)

    Henning Hagmann

    Full Text Available RATIONALE: Preeclampsia is a devastating medical complication of pregnancy which leads to maternal and fetal morbidity and mortality. While the etiology of preeclampsia is unclear, human and animal studies suggest that excessive circulating levels of soluble fms-like tyrosine-kinase-1 (sFlt-1, an alternatively spliced variant of VEGF-receptor1, contribute to the signs and symptoms of preeclampsia. Since sFlt-1 binds to heparin and heparan sulfate proteoglycans, we hypothesized that the anticoagulant heparin, which is often used in pregnancy, may interfere with the levels, distribution and elimination of sFlt-1 in vivo. OBJECTIVE: We systematically determined serum and urine levels of angiogenic factors in preeclamptic women before and after administration of low molecular weight heparin and further characterized the interaction with heparin in biochemical studies. METHODS AND RESULTS: Serum and urine samples were used to measure sFlt-1 levels before and after heparin administration. Serum levels of sFlt-1 increased by 25% after heparin administration in pregnant women. The magnitude of the increase in circulating sFlt-1 correlated with initial sFlt-1 serum levels. Urinary sFlt-1 levels were also elevated following heparin administration and levels of elimination were dependent on the underlying integrity of the glomerular filtration barrier. Biochemical binding studies employing cation exchange chromatography revealed that heparin bound sFlt-1 had decreased affinity to negatively charged surfaces when compared to sFlt-1 alone. CONCLUSION: Low molecular weight heparin administration increased circulating sFlt1 levels and enhanced renal elimination. We provide evidence that both effects may be due to heparin binding to sFlt1 and masking the positive charges on sFlt1 protein.

  10. Intranasal epidermal growth factor treatment rescues neonatal brain injury

    Science.gov (United States)

    Scafidi, Joseph; Hammond, Timothy R.; Scafidi, Susanna; Ritter, Jonathan; Jablonska, Beata; Roncal, Maria; Szigeti-Buck, Klara; Coman, Daniel; Huang, Yuegao; McCarter, Robert J.; Hyder, Fahmeed; Horvath, Tamas L.; Gallo, Vittorio

    2014-02-01

    There are no clinically relevant treatments available that improve function in the growing population of very preterm infants (less than 32 weeks' gestation) with neonatal brain injury. Diffuse white matter injury (DWMI) is a common finding in these children and results in chronic neurodevelopmental impairments. As shown recently, failure in oligodendrocyte progenitor cell maturation contributes to DWMI. We demonstrated previously that the epidermal growth factor receptor (EGFR) has an important role in oligodendrocyte development. Here we examine whether enhanced EGFR signalling stimulates the endogenous response of EGFR-expressing progenitor cells during a critical period after brain injury, and promotes cellular and behavioural recovery in the developing brain. Using an established mouse model of very preterm brain injury, we demonstrate that selective overexpression of human EGFR in oligodendrocyte lineage cells or the administration of intranasal heparin-binding EGF immediately after injury decreases oligodendroglia death, enhances generation of new oligodendrocytes from progenitor cells and promotes functional recovery. Furthermore, these interventions diminish ultrastructural abnormalities and alleviate behavioural deficits on white-matter-specific paradigms. Inhibition of EGFR signalling with a molecularly targeted agent used for cancer therapy demonstrates that EGFR activation is an important contributor to oligodendrocyte regeneration and functional recovery after DWMI. Thus, our study provides direct evidence that targeting EGFR in oligodendrocyte progenitor cells at a specific time after injury is clinically feasible and potentially applicable to the treatment of premature children with white matter injury.

  11. Selective interaction of heparin with the variable region 3 within surface glycoprotein of laboratory-adapted feline immunodeficiency virus.

    Directory of Open Access Journals (Sweden)

    Qiong-Ying Hu

    Full Text Available Heparan sulfate proteoglycans (HSPG can act as binding receptors for certain laboratory-adapted (TCA strains of feline immunodeficiency virus (FIV and human immunodeficiency virus (HIV. Heparin, a soluble heparin sulfate (HS, can inhibit TCA HIV and FIV entry mediated by HSPG interaction in vitro. In the present study, we further determined the selective interaction of heparin with the V3 loop of TCA of FIV. Our current results indicate that heparin selectively inhibits infection by TCA strains, but not for field isolates (FS. Heparin also specifically interferes with TCA surface glycoprotein (SU binding to CXCR4, by interactions with HSPG binding sites on the V3 loop of the FIV envelope protein. Peptides representing either the N- or C-terminal side of the V3 loop and containing HSPG binding sites were able to compete away the heparin block of TCA SU binding to CXCR4. Heparin does not interfere with the interaction of SU with anti-V3 antibodies that target the CXCR4 binding region or with the interaction between FS FIV and anti-V3 antibodies since FS SU has no HSPG binding sites within the HSPG binding region. Our data show that heparin blocks TCA FIV infection or entry not only through its competition of HSPG on the cell surface interaction with SU, but also by its interference with CXCR4 binding to SU. These studies aid in the design and development of heparin derivatives or analogues that can inhibit steps in virus infection and are informative regarding the HSPG/SU interaction.

  12. Sequence-specific 1H NMR assignments, secondary structure, and location of the calcium binding site in the first epidermal growth factor like domain of blood coagulation factor IX

    International Nuclear Information System (INIS)

    Huang, L.H.; Cheng, H.; Sweeney, W.V.; Pardi, A.; Tam, J.P.

    1991-01-01

    Factor IX is a blood clotting protein that contains three regions, including a γ-carboxyglutamic acid (Gla) domain, two tandemly connected epidermal growth factor like (EGF-like) domains, and a serine protease region. The protein exhibits a high-affinity calcium binding site in the first EGF0like domain, in addition to calcium binding in the Gla domain. The first EGF-like domain, factor IX (45-87), has been synthesized. Sequence-specific resonance assignment of the peptide has been made by using 2D NMR techniques, and its secondary structure has been determined. The protein is found to have two antiparallel β-sheets, and preliminary distance geometry calculations indicate that the protein has two domains, separated by Trp 28 , with the overall structure being similar to that of EGF. An NMR investigation of the calcium-bound first EGF-like domain indicates the presence and location of a calcium binding site involving residues on both strands of one of the β-sheets as well as the N-terminal region of the peptide. These results suggest that calcium binding in the first EGF-like domain could induce long-range (possibly interdomain) conformational changes in factor IX, rather than causing structural alterations in the EGF-like domain itself

  13. Internalization mechanisms of the epidermal growth factor receptor after activation with different ligands.

    Directory of Open Access Journals (Sweden)

    Lasse Henriksen

    Full Text Available The epidermal growth factor receptor (EGFR regulates normal growth and differentiation, but dysregulation of the receptor or one of the EGFR ligands is involved in the pathogenesis of many cancers. There are eight ligands for EGFR, however most of the research into trafficking of the receptor after ligand activation focuses on the effect of epidermal growth factor (EGF and transforming growth factor-α (TGF-α. For a long time it was believed that clathrin-mediated endocytosis was the major pathway for internalization of the receptor, but recent work suggests that different pathways exist. Here we show that clathrin ablation completely inhibits internalization of EGF- and TGF-α-stimulated receptor, however the inhibition of receptor internalization in cells treated with heparin-binding EGF-like growth factor (HB-EGF or betacellulin (BTC was only partial. In contrast, clathrin knockdown fully inhibits EGFR degradation after all ligands tested. Furthermore, inhibition of dynamin function blocked EGFR internalization after stimulation with all ligands. Knocking out a number of clathrin-independent dynamin-dependent pathways of internalization had no effect on the ligand-induced endocytosis of the EGFR. We suggest that EGF and TGF-α lead to EGFR endocytosis mainly via the clathrin-mediated pathway. Furthermore, we suggest that HB-EGF and BTC also lead to EGFR endocytosis via a clathrin-mediated pathway, but can additionally use an unidentified internalization pathway or better recruit the small amount of clathrin remaining after clathrin knockdown.

  14. Internalization Mechanisms of the Epidermal Growth Factor Receptor after Activation with Different Ligands

    Science.gov (United States)

    Henriksen, Lasse; Grandal, Michael Vibo; Knudsen, Stine Louise Jeppe; van Deurs, Bo; Grøvdal, Lene Melsæther

    2013-01-01

    The epidermal growth factor receptor (EGFR) regulates normal growth and differentiation, but dysregulation of the receptor or one of the EGFR ligands is involved in the pathogenesis of many cancers. There are eight ligands for EGFR, however most of the research into trafficking of the receptor after ligand activation focuses on the effect of epidermal growth factor (EGF) and transforming growth factor-α (TGF-α). For a long time it was believed that clathrin-mediated endocytosis was the major pathway for internalization of the receptor, but recent work suggests that different pathways exist. Here we show that clathrin ablation completely inhibits internalization of EGF- and TGF-α-stimulated receptor, however the inhibition of receptor internalization in cells treated with heparin-binding EGF-like growth factor (HB-EGF) or betacellulin (BTC) was only partial. In contrast, clathrin knockdown fully inhibits EGFR degradation after all ligands tested. Furthermore, inhibition of dynamin function blocked EGFR internalization after stimulation with all ligands. Knocking out a number of clathrin-independent dynamin-dependent pathways of internalization had no effect on the ligand-induced endocytosis of the EGFR. We suggest that EGF and TGF-α lead to EGFR endocytosis mainly via the clathrin-mediated pathway. Furthermore, we suggest that HB-EGF and BTC also lead to EGFR endocytosis via a clathrin-mediated pathway, but can additionally use an unidentified internalization pathway or better recruit the small amount of clathrin remaining after clathrin knockdown. PMID:23472148

  15. N-acetyl-heparin attenuates acute lung injury caused by acid aspiration mainly by antagonizing histones in mice.

    Science.gov (United States)

    Zhang, Yanlin; Zhao, Zanmei; Guan, Li; Mao, Lijun; Li, Shuqiang; Guan, Xiaoxu; Chen, Ming; Guo, Lixia; Ding, Lihua; Cong, Cuicui; Wen, Tao; Zhao, Jinyuan

    2014-01-01

    Acute lung injury (ALI) is the leading cause of death in intensive care units. Extracellular histones have recently been recognized to be pivotal inflammatory mediators. Heparin and its derivatives can bind histones through electrostatic interaction. The purpose of this study was to investigate 1) the role of extracellular histones in the pathogenesis of ALI caused by acid aspiration and 2) whether N-acetyl-heparin (NAH) provides more protection than heparin against histones at the high dose. ALI was induced in mice via intratracheal instillation of hydrochloric acid (HCl). Lethality rate, blood gas, myeloperoxidase (MPO) activity, lung edema and pathological changes were used to evaluate the degree of ALI. Heparin/NAH was administered intraperitoneally, twice a day, for 3 days or until death. Acid aspiration caused an obvious increase in extracellular histones. A significant correlation existed between the concentration of HCl aspirated and the circulating histones. Heparin/NAH (10 mg/kg) improved the lethality rate, blood gas, MPO activity, lung edema and pathological score. At a dose of 20 mg/kg, NAH still provided protection, however heparin tended to aggravate the injury due to hemorrhagic complications. The specific interaction between heparin and histones was verified by the binding assay. In summary, high levels of extracellular histones can be pathogenic in ALI caused by acid aspiration. By neutralizing extracellular histones, heparin/NAH can offer similar protection at the moderate doses. At the high dose, NAH provides better protection than heparin.

  16. Early events elicited by Bombesin and structurally related peptides in quiescent Swiss 3T3 cells. I. Activation of protein kinase C and inhibition of epidermal growth factor binding

    International Nuclear Information System (INIS)

    Zachary, I.; Sinnett-Smith, J.W.; Rozengurt, E.

    1986-01-01

    Addition of bombesin to quiescent cultures of Swiss 3T3 cells caused a rapid increase in the phosphorylation of an M/sub r/ 80,000 cellular protein (designated 80k). The effect was both concentration and time dependent. The 80k phosphoproteins generated in response to bombesin and to phorbol 12,13-dibutyrate were identical as judged by one- and two-dimensional PAGE and by peptide mapping after partial proteolysis with Staphylococcus aureus V8 protease. In addition, prolonged pretreatment of 3T3 cells with phorbol 12,13-dibutyrate, which leads to the disappearance of protein kinase C activity, blocked the ability of bombesin to stimulate 80k. Bombesin also caused a rapid (1 min) inhibition of 125 I-labeled epidermal growth factor ( 125 I-EGF) binding to Swiss 3T3 cells. The inhibition was both concentration and temperature dependent and resulted from a marked decrease in the affinity of the EGF receptor for its ligand. These results strongly suggest that these responses are mediated by specific high-affinity receptors that recognize the peptides of the bombesin family in Swiss 3T3 cells. While an increase in cytosolic Ca 2+ concentration does not mediate the bombesin inhibition of 125 I-EGF binding, the activation of protein kinase C in intact Swiss 3T3 cells by peptides of the bombesin family may lead to rapid inhibition of the binding of 125 I-EGF to its cellular receptor

  17. How to give a heparin shot

    Science.gov (United States)

    ... you put the injection. Storing Your Heparin and Supplies Ask your pharmacist how to store your heparin ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  18. Neural cell adhesion molecule-180-mediated homophilic binding induces epidermal growth factor receptor (EGFR) down-regulation and uncouples the inhibitory function of EGFR in neurite outgrowth

    DEFF Research Database (Denmark)

    Povlsen, Gro Klitgaard; Berezin, Vladimir; Bock, Elisabeth

    2008-01-01

    The neural cell adhesion molecule (NCAM) plays important roles in neuronal development, regeneration, and synaptic plasticity. NCAM homophilic binding mediates cell adhesion and induces intracellular signals, in which the fibroblast growth factor receptor plays a prominent role. Recent studies...... this NCAM-180-induced EGFR down-regulation involves increased EGFR ubiquitination and lysosomal EGFR degradation. Furthermore, NCAM-180-mediated EGFR down-regulation requires NCAM homophilic binding and interactions of the cytoplasmic domain of NCAM-180 with intracellular interaction partners, but does...

  19. Eldecalcitol (ED-71), an analog of 1α,25(OH)2D3, inhibits the growth of squamous cell carcinoma (SCC) cells in vitro and in vivo by down-regulating expression of heparin-binding protein 17/fibroblast growth factor-binding protein-1 (HBp17/FGFBP-1) and FGF-2.

    Science.gov (United States)

    Shintani, T; Takatsu, F; Rosli, S N Z; Usui, E; Hamada, A; Sumi, K; Hayashido, Y; Toratani, S; Okamoto, Tetsuji

    2017-10-01

    Heparin-binding protein 17 (HBp17)/fibroblast growth factor-binding protein-1 (FGFBP-1) was first purified from medium conditioned by A431 cells for its capacity to bind to fibroblast growth factors 1 and 2 (FGF-1 and -2). Among FGF family members, FGF-2 is a potent mitogen for various cell types, including vascular endothelial cells, fibroblasts, and cancer cells such as oral squamous cell carcinoma (OSCC) cells. Besides being well known in bone metabolism, the active form of vitamin D 3 , i.e., 1α,25(OH) 2 D 3 (1,25D 3 ), was reported to have protective effects for heart disease and cancer. Previously, we reported that 1,25D 3 inhibited HBp17/FGFBP-1 expression in OSCC cell lines through NF-κB inhibition (IκBα activation) and resulted in the inactivation of FGF-2. In this study, we examined the potential anti-tumor effect of ED-71, an analog of 1α,25(OH) 2 D 3 , for squamous cell carcinoma cells in vitro and in vivo. The cell lines used were OSCC cell lines (NA-HO-1-n-1 and UE-HO-1-u-1), established from oral cancer patients in our laboratory, and an epidermoid carcinoma/SCC cell line (A431). The growth assay in serum-free culture revealed that ED-71 inhibited the growth of the cancer cell lines in a dose-dependent manner. In addition, ED-71 suppressed HBp17/FGFBP-1 expression by inhibiting the NF-κB pathway as did 1,25D 3 . Furthermore, a luciferase reporter assay revealed that the promoter activity of HBp17/FGFBP-1 (region between -217 and +61) was down-regulated by ED-71. Oral administration of ED-71 significantly inhibited the growth of A431-derived tumors in athymic nude mice. Immunohistochemical analysis revealed that the expression of HBp17/FGFBP-1, FGF-2, CD31, and Ki-67 in the tumors of ED71-treated group was down-regulated in comparison to control. These results suggest that ED-71 possesses potential anti-tumor activity for SCCs both in vitro and in vivo. This compound may act directly on the tumor cells or on endothelial cells by modulating the

  20. Interference of heparin in carcinoembryonic antigen radioimmunoassays

    International Nuclear Information System (INIS)

    Wu, J.T.

    1983-01-01

    A false Roche carcinoembryonic antigen (CEA) activity could be detected in all commercial and noncommercial heparin preparations examined. The possibility of 'due to contamination' has been ruled out. Using the Roche procedure, heparin solutions, in the absence of CEA, gave positive CEA activity; on the other hand, no CEA activity was detected in solutions containing only heparin when the Abbott Kit was used. When heparin was present in specimens containing CEA, the Abbott Kit underestimated the CEA activity, whereas the Roche Kit gave false elevated values. However, the negative effect of heparin could be reduced by heat treatment in the presence of plasma proteins. (Auth.)

  1. A role for calcium in the regulation of ATP-binding cassette, sub-family C, member 3 (ABCC3) gene expression in a model of epidermal growth factor-mediated breast cancer epithelial-mesenchymal transition.

    Science.gov (United States)

    Stewart, Teneale A; Azimi, Iman; Thompson, Erik W; Roberts-Thomson, Sarah J; Monteith, Gregory R

    2015-03-13

    Epithelial-mesenchymal transition (EMT), a process implicated in cancer metastasis, is associated with the transcriptional regulation of members of the ATP-binding cassette superfamily of efflux pumps, and drug resistance in breast cancer cells. Epidermal growth factor (EGF)-induced EMT in MDA-MB-468 breast cancer cells is calcium signal dependent. In this study induction of EMT was shown to result in the transcriptional up-regulation of ATP-binding cassette, subfamily C, member 3 (ABCC3), a member of the ABC transporter superfamily, which has a recognized role in multidrug resistance. Buffering of cytosolic free calcium inhibited EGF-mediated ABCC3 increases, indicating a calcium-dependent mode of regulation. Silencing of TRPM7 (an ion channel involved in EMT associated vimentin induction) did not inhibit ABCC3 up-regulation. Silencing of the store operated calcium entry (SOCE) pathway components ORAI1 and STIM1 also did not alter ABCC3 induction by EGF. However, the calcium permeable ion channel transient receptor potential cation channel, subfamily C, member 1 (TRPC1) appears to contribute to the regulation of both basal and EGF-induced ABCC3 mRNA. Improved understanding of the relationship between calcium signaling, EMT and the regulation of genes important in therapeutic resistance may help identify novel therapeutic targets for breast cancer. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. The SRC homology 2 domain of Rin1 mediates its binding to the epidermal growth factor receptor and regulates receptor endocytosis.

    Science.gov (United States)

    Barbieri, M Alejandro; Kong, Chen; Chen, Pin-I; Horazdovsky, Bruce F; Stahl, Philip D

    2003-08-22

    Activated epidermal growth factor receptors (EGFRs) recruit intracellular proteins that mediate receptor signaling and endocytic trafficking. Rin1, a multifunctional protein, has been shown to regulate EGFR internalization (1). Here we show that EGF stimulation induces a specific, rapid, and transient membrane recruitment of Rin1 and that recruitment is dependent on the Src homology 2 (SH2) domain of Rin1. Immunoprecipitation of EGFR is accompanied by co-immunoprecipitation of Rin1 in a time- and ligand-dependent manner. Association of Rin1 and specifically the SH2 domain of Rin1 with the EGFR was dependent on tyrosine phosphorylation of the intracellular domain of the EGFR. The recruitment of Rin1, observed by light microscopy, indicated that although initially cytosolic, Rin1 was recruited to both plasma membrane and endosomes following EGF addition. Moreover, the expression of the SH2 domain of Rin1 substantially impaired the internalization of EGF without affecting internalization of transferrin. Finally, we found that Rin1 co-immunoprecipitated with a number of tyrosine kinase receptors but not with cargo endocytic receptors. These results indicate that Rin1 provides a link via its SH2 domain between activated tyrosine kinase receptors and the endocytic pathway through the recruitment and activation of Rab5a.

  3. Cell-cell adhesion mediated by binding of membrane-anchored transforming growth factor α to epidermal growth factor receptors promotes cell proliferation

    International Nuclear Information System (INIS)

    Anklesaria, P.; Greenberger, J.S.; Teixido, J.; Laiho, M.; Massague, J.; Pierce, J.H.

    1990-01-01

    The precursor for transforming growth factor α, pro-TGF-α, is a cell surface glycoprotein that can establish contact with epidermal growth factor (EGF) receptors on adjacent cells. To examine whether the pro-TGF-α/EGF receptor pair can simultaneously mediate cell adhesion and promote cell proliferation, the authors have expressed pro-TGF-α in a bone marrow stromal cell line labeled with [ 35 S] cysteine. Expression of pro-TGF-α allows these cells to support long-term attachment of an EGF/interleukin-3-dependent hematopoietic progenitor cell line that expresses EGF receptors but is unable to adhere to normal stroma. This interaction is inhibited by soluble EGF receptor ligands. Further, the hematopoietic progenitor cells replicate their DNA while they are attached to the stromal cell layer and become foci of sustained cell proliferation. Thus, pro-TGF-α and the EGF receptor can function as mediators of intercellular adhesion and this interaction may promote a mitogenic response. They propose the term juxtacrine to designate this form of stimulation between adjacent cells

  4. Analysis and characterization of heparin impurities.

    Science.gov (United States)

    Beni, Szabolcs; Limtiaco, John F K; Larive, Cynthia K

    2011-01-01

    This review discusses recent developments in analytical methods available for the sensitive separation, detection and structural characterization of heparin contaminants. The adulteration of raw heparin with oversulfated chondroitin sulfate (OSCS) in 2007-2008 spawned a global crisis resulting in extensive revisions to the pharmacopeia monographs on heparin and prompting the FDA to recommend the development of additional physicochemical methods for the analysis of heparin purity. The analytical chemistry community quickly responded to this challenge, developing a wide variety of innovative approaches, several of which are reported in this special issue. This review provides an overview of methods of heparin isolation and digestion, discusses known heparin contaminants, including OSCS, and summarizes recent publications on heparin impurity analysis using sensors, near-IR, Raman, and NMR spectroscopy, as well as electrophoretic and chromatographic separations.

  5. A cyclic peptide derived from alpha-fetoprotein inhibits the proliferative effects of the epidermal growth factor and estradiol in MCF7 cells.

    Science.gov (United States)

    Torres, Cristian; Antileo, Elmer; Epuñán, Maráa José; Pino, Ana María; Valladares, Luis Emilio; Sierralta, Walter Daniel

    2008-06-01

    A cyclic peptide derived from the active domain of alpha-fetoprotein (AFP) significantly inhibited the proliferation of MCF7 cells stimulated with the epidermal growth factor (EGF) or estradiol (E2). The action of these three agents on cell growth was independent of the presence of calf serum in the culture medium. Our results demonstrated that the cyclic peptide interfered markedly with the regulation of MAPK by activated c-erbB2. The cyclic peptide showed no effect on the E2-stimulated release of matrix metalloproteinases 2 and 9 nor on the shedding of heparin-binding EGF into the culture medium. We propose that the AFP-derived cyclic peptide represents a valuable novel antiproliferative agent for treating breast cancer.

  6. Recurrent exposure to nicotine differentiates human bronchial epithelial cells via epidermal growth factor receptor activation

    International Nuclear Information System (INIS)

    Martinez-Garcia, Eva; Irigoyen, Marta; Anso, Elena; Martinez-Irujo, Juan Jose; Rouzaut, Ana

    2008-01-01

    Cigarette smoking is the major preventable cause of lung cancer in developed countries. Nicotine (3-(1-methyl-2-pyrrolidinyl)-pyridine) is one of the major alkaloids present in tobacco. Besides its addictive properties, its effects have been described in panoply of cell types. In fact, recent studies have shown that nicotine behaves as a tumor promoter in transformed epithelial cells. This research focuses on the effects of acute repetitive nicotine exposure on normal human bronchial epithelial cells (NHBE cells). Here we show that treatment of NHBE cells with recurrent doses of nicotine up to 500 μM triggered cell differentiation towards a neuronal-like phenotype: cells emitted filopodia and expressed neuronal markers such as neuronal cell adhesion molecule, neurofilament-M and the transcription factors neuronal N and Pax-3. We also demonstrate that nicotine treatment induced NF-kB translocation to the nucleus, phosphorylation of the epidermal growth factor receptor (EGFR), and accumulation of heparin binding-EGF in the extracellular medium. Moreover, addition of AG1478, an inhibitor of EGFR tyrosine phosphorylation, or cetuximab, a monoclonal antibody that precludes ligand binding to the same receptor, prevented cell differentiation by nicotine. Lastly, we show that differentiated cells increased their adhesion to the extracellular matrix and their protease activity. Given that several lung pathologies are strongly related to tobacco consumption, these results may help to better understand the damaging consequences of nicotine exposure

  7. Structure-Activity Relationships of Bioengineered Heparin/Heparan Sulfates Produced in Different Bioreactors

    Directory of Open Access Journals (Sweden)

    Ha Na Kim

    2017-05-01

    Full Text Available Heparin and heparan sulfate are structurally-related carbohydrates with therapeutic applications in anticoagulation, drug delivery, and regenerative medicine. This study explored the effect of different bioreactor conditions on the production of heparin/heparan sulfate chains via the recombinant expression of serglycin in mammalian cells. Tissue culture flasks and continuously-stirred tank reactors promoted the production of serglycin decorated with heparin/heparan sulfate, as well as chondroitin sulfate, while the serglycin secreted by cells in the tissue culture flasks produced more highly-sulfated heparin/heparan sulfate chains. The serglycin produced in tissue culture flasks was effective in binding and signaling fibroblast growth factor 2, indicating the utility of this molecule in drug delivery and regenerative medicine applications in addition to its well-known anticoagulant activity.

  8. Metabolic engineering of Chinese hamster ovary cells: towards a bioengineered heparin.

    Science.gov (United States)

    Baik, Jong Youn; Gasimli, Leyla; Yang, Bo; Datta, Payel; Zhang, Fuming; Glass, Charles A; Esko, Jeffrey D; Linhardt, Robert J; Sharfstein, Susan T

    2012-03-01

    Heparin is the most widely used pharmaceutical to control blood coagulation in modern medicine. A health crisis that took place in 2008 led to a demand for production of heparin from non-animal sources. Chinese hamster ovary (CHO) cells, commonly used mammalian host cells for production of foreign pharmaceutical proteins in the biopharmaceutical industry, are capable of producing heparan sulfate (HS), a related polysaccharide naturally. Since heparin and HS share the same biosynthetic pathway, we hypothesized that heparin could be produced in CHO cells by metabolic engineering. Based on the expression of endogenous enzymes in the HS/heparin pathways of CHO-S cells, human N-deacetylase/N-sulfotransferase (NDST2) and mouse heparan sulfate 3-O-sulfotransferase 1 (Hs3st1) genes were transfected sequentially into CHO host cells growing in suspension culture. Transfectants were screened using quantitative RT-PCR and Western blotting. Out of 120 clones expressing NDST2 and Hs3st1, 2 clones, Dual-3 and Dual-29, were selected for further analysis. An antithrombin III (ATIII) binding assay using flow cytometry, designed to recognize a key sugar structure characteristic of heparin, indicated that Hs3st1 transfection was capable of increasing ATIII binding. An anti-factor Xa assay, which affords a measure of anticoagulant activity, showed a significant increase in activity in the dual-expressing cell lines. Disaccharide analysis of the engineered HS showed a substantial increase in N-sulfo groups, but did not show a pattern consistent with pharmacological heparin, suggesting that further balancing the expression of transgenes with the expression levels of endogenous enzymes involved in HS/heparin biosynthesis might be necessary. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Low molecular weight heparin versus unfractionated heparin in the initial treatment of venous thromboembolism

    NARCIS (Netherlands)

    Hettiarachchi, R. J.; Prins, M. H.; Lensing, A. W.; Buller, H. R.

    1998-01-01

    In this review, we analyze data from randomized trials in which low molecular weight heparin was compared with unfractionated heparin, both to estimate the treatment effect of low molecular weight heparin in the initial treatment of venous thromboembolism and to evaluate the effect of the varied

  10. Unfractionated heparin versus low molecular weight heparins for avoiding heparin-induced thrombocytopenia in postoperative patients.

    Science.gov (United States)

    Junqueira, Daniela R; Zorzela, Liliane M; Perini, Edson

    2017-04-21

    Heparin-induced thrombocytopenia (HIT) is an adverse drug reaction presenting as a prothrombotic disorder related to antibody-mediated platelet activation. It is a paradoxical immune reaction resulting in thrombin generation in vivo, which leads to a hypercoagulable state and the potential to initiate venous or arterial thrombosis. A number of factors are thought to influence the incidence of HIT including the type and preparation of heparin (unfractionated heparin (UFH) or low molecular weight heparin (LMWH)) and the heparin-exposed patient population, with the postoperative patient population at higher risk.Although LMWH has largely replaced UFH as a front-line therapy, there is evidence supporting a lack of superiority of LMWH compared with UFH regarding prevention of deep vein thrombosis and pulmonary embolism following surgery, and similar frequencies of bleeding have been described with LMWH and UFH. The decision as to which of these two preparations of heparin to use may thus be influenced by harmful effects such as HIT. We therefore sought to determine the relative impact of UFH and LMWH on HIT in postoperative patients receiving thromboembolism prophylaxis. This is an update of a review first published in 2012. The objective of this review was to compare the incidence of heparin-induced thrombocytopenia (HIT) and HIT complicated by venous thromboembolism in postoperative patients exposed to unfractionated heparin (UFH) versus low molecular weight heparin (LMWH). For this update, the Cochrane Vascular Information Specialist searched the Specialised Register (May 2016), CENTRAL (2016, Issue 4) and trials registries. The authors searched Lilacs (June 2016) and additional trials were sought from reference lists of relevant publications. We included randomised controlled trials (RCTs) in which participants were postoperative patients allocated to receive prophylaxis with UFH or LMWH, in a blinded or unblinded fashion. Studies were excluded if they did not use

  11. Parent heparin and daughter LMW heparin correlation analysis using LC-MS and NMR

    International Nuclear Information System (INIS)

    Liu, Xinyue; St Ange, Kalib; Wang, Xiaohua; Lin, Lei; Zhang, Fuming

    2017-01-01

    Heparin is a structurally complex, polysaccharide anticoagulant derived from livestock, primarily porcine intestinal tissues. Low molecular weight (LMW) heparins are derived through the controlled partial depolymerization of heparin. Increased manufacturing and regulatory concerns have provided the motivation for the development of more sophisticated analytical methods for determining both their structure and pedigree. A strategy, for the comprehensive comparison of parent heparins and their LMW heparin daughters, is described that relies on the analysis of monosaccharide composition, disaccharide composition, and oligosaccharide composition. Liquid chromatography-mass spectrometry is rapid, robust, and amenable to automated processing and interpretation of both top-down and bottom-up analyses. Nuclear magnetic resonance spectroscopy provides complementary top-down information on the chirality of the uronic acid residues and glucosamine substitution. Principal component analysis (PCA) was applied to the normalized abundance of oligosaccharides, calculated in the bottom-up analysis, to show parent and daughter correlation in oligosaccharide composition. Using these approaches, six pairs of parent heparins and their daughter generic enoxaparins from two different manufacturers were comprehensively analyzed. Enoxaparin is the most widely used LMW heparin and is prepared through controlled chemical β-eliminative cleavage of porcine intestinal heparin. Lovenox"®, the innovator version of enoxaparin marketed in the US, was analyzed as a reference for the daughter LMW heparins. The results, show similarities between LMW heparins from two different manufacturers with Lovenox"®, excellent lot-to-lot consistency of products from each manufacturer, and detects a correlation between each parent heparin and daughter LMW heparin. - Highlights: • Low molecular weight heparins prepared from different heparin parents were analyzed. • An integrated analytical approach relied

  12. Parent heparin and daughter LMW heparin correlation analysis using LC-MS and NMR

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xinyue, E-mail: liux22@rpi.edu [National Glycoengineering Research Center, Shandong Provincial Key Laboratory of Carbohydrate Chemistry and Glycobiology, State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, 250100 (China); Department of Chemistry and Chemical Biology, Department of Chemical and Biological Engineering, Department of Biology, Department of Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180 (United States); St Ange, Kalib, E-mail: stangk2@rpi.edu [Department of Chemistry and Chemical Biology, Department of Chemical and Biological Engineering, Department of Biology, Department of Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180 (United States); Wang, Xiaohua, E-mail: wangx35@rpi.edu [Department of Chemistry and Chemical Biology, Department of Chemical and Biological Engineering, Department of Biology, Department of Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180 (United States); School of Computer and Information, Hefei University of Technology, Hefei (China); Lin, Lei, E-mail: Linl5@rpi.edu [Department of Chemistry and Chemical Biology, Department of Chemical and Biological Engineering, Department of Biology, Department of Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180 (United States); Zhang, Fuming, E-mail: zhangf2@rpi.edu [Department of Chemistry and Chemical Biology, Department of Chemical and Biological Engineering, Department of Biology, Department of Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180 (United States); and others

    2017-04-08

    Heparin is a structurally complex, polysaccharide anticoagulant derived from livestock, primarily porcine intestinal tissues. Low molecular weight (LMW) heparins are derived through the controlled partial depolymerization of heparin. Increased manufacturing and regulatory concerns have provided the motivation for the development of more sophisticated analytical methods for determining both their structure and pedigree. A strategy, for the comprehensive comparison of parent heparins and their LMW heparin daughters, is described that relies on the analysis of monosaccharide composition, disaccharide composition, and oligosaccharide composition. Liquid chromatography-mass spectrometry is rapid, robust, and amenable to automated processing and interpretation of both top-down and bottom-up analyses. Nuclear magnetic resonance spectroscopy provides complementary top-down information on the chirality of the uronic acid residues and glucosamine substitution. Principal component analysis (PCA) was applied to the normalized abundance of oligosaccharides, calculated in the bottom-up analysis, to show parent and daughter correlation in oligosaccharide composition. Using these approaches, six pairs of parent heparins and their daughter generic enoxaparins from two different manufacturers were comprehensively analyzed. Enoxaparin is the most widely used LMW heparin and is prepared through controlled chemical β-eliminative cleavage of porcine intestinal heparin. Lovenox{sup ®}, the innovator version of enoxaparin marketed in the US, was analyzed as a reference for the daughter LMW heparins. The results, show similarities between LMW heparins from two different manufacturers with Lovenox{sup ®}, excellent lot-to-lot consistency of products from each manufacturer, and detects a correlation between each parent heparin and daughter LMW heparin. - Highlights: • Low molecular weight heparins prepared from different heparin parents were analyzed. • An integrated analytical

  13. Heparin-based hydrogels with tunable sulfation & degradation for anti-inflammatory small molecule delivery.

    Science.gov (United States)

    Peng, Yifeng; Tellier, Liane E; Temenoff, Johnna S

    2016-08-16

    Sustained release of anti-inflammatory agents remains challenging for small molecule drugs due to their low molecular weight and hydrophobicity. Therefore, the goal of this study was to control the release of a small molecule anti-inflammatory agent, crystal violet (CV), from hydrogels fabricated with heparin, a highly sulfated glycosaminoglycan capable of binding positively-charged molecules such as CV. In this system, both electrostatic interactions between heparin and CV and hydrogel degradation were tuned simultaneously by varying the level of heparin sulfation and varying the amount of dithiothreitol within hydrogels, respectively. It was found that heparin sulfation significantly affected CV release, whereby more sulfated heparin hydrogels (Hep and Hep(-N)) released CV with near zero-order release kinetics (R-squared values between 0.96-0.99). Furthermore, CV was released more quickly from fast-degrading hydrogels than slow-degrading hydrogels, providing a method to tune total CV release between 5-15 days while maintaining linear release kinetics. In particular, N-desulfated heparin hydrogels exhibited efficient CV loading (∼90% of originally included CV), near zero-order CV release kinetics, and maintenance of CV bioactivity after release, making this hydrogel formulation a promising CV delivery vehicle for a wide range of inflammatory diseases.

  14. Purification of foot-and-mouth disease virus by heparin as ligand for certain strains.

    Science.gov (United States)

    Du, Ping; Sun, Shiqi; Dong, Jinjie; Zhi, Xiaoying; Chang, Yanyan; Teng, Zhidong; Guo, Huichen; Liu, Zaixin

    2017-04-01

    The goal of this project was to develop an easily operable and scalable process for the recovery and purification of foot-and-mouth disease virus (FMDV) from cell culture. Heparin resins HipTrap Heparin HP and AF-Heparin HC-650 were utilized to purify FMDV O/HN/CHA/93. Results showed that the purity of AF-Heparin HC-650 was ideal. Then, the O/HN/CHA/93, O/Tibet/CHA/99, Asia I/HN/06, and A/CHA/HB/2009 strains were purified by AF-Heparin HC-650. Their affinity/virus recoveries were approximately 51.2%/45.8%, 71.5%/70.9%, 96.4%/73.5, and 59.5%/42.1%, respectively. During a stepwise elution strategy, the viral particles were mainly eluted at 300mM ionic strength peaks. The heparin affinity chromatography process removed more than 94% of cellular and medium proteins. Anion exchange resin Capto Q captured four FMD virus particles; 40% of binding proteins and 80%-90% of viral particles were eluted at 450mM NaCl. Moreover, ionic strength varied from 30 to 450mM had no effect on the immunity to FMDV. The results revealed that heparin sulfate may be the main receptor for CHA/99 strain attachment-susceptible cells. Heparin affinity chromatography can reach perfect results, especially when used as a ligand of the virus. Anion exchange is useful only as previous step for further purification. Copyright © 2016. Published by Elsevier B.V.

  15. Sterilization of heparinized cuprophan hemodialysis membranes

    NARCIS (Netherlands)

    ten Hoopen, Hermina W.M.; Hinrichs, W.L.J.; Hinrichs, W.L.J.; Engbers, G.H.M.; Feijen, Jan

    1996-01-01

    The effects of sterilization of dry heparinized Cuprophan hemodialysis membranes by means of ethylene oxide (EtO) exposure, gamma irradiation, or steam on the anticoagulant activity and chemical characteristics of immobilized heparin and the permeability of the membrane were investigated.

  16. 21 CFR 864.7525 - Heparin assay.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Heparin assay. 864.7525 Section 864.7525 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7525 Heparin assay. (a) Identification. A...

  17. Allergic anaphylaxis due to subcutaneously injected heparin

    Directory of Open Access Journals (Sweden)

    Anders Diana

    2013-01-01

    Full Text Available Abstract Heparins are one of the most used class of anticoagulants in daily clinical practice. Despite their widespread application immune-mediated hypersensitivity reactions to heparins are rare. Among these, the delayed-type reactions to s.c. injected heparins are well-known usually presenting as circumscribed eczematous plaques at the injection sites. In contrast, potentially life-threatening systemic immediate-type anaphylactic reactions to heparins are extremely rare. Recently, some cases of non-allergic anaphylaxis could be attributed to undesirable heparin contaminants. A 43-year-old patient developed severe anaphylaxis symptoms within 5–10 minutes after s.c. injection of enoxaparin. Titrated skin prick testing with wheal and flare responses up to an enoxaparin dilution of 1:10.000 indicated a probable allergic mechanism of the enoxaparin-induced anaphylaxis. The basophil activation test as an additional in-vitro test method was negative. Furthermore, skin prick testing showed rather broad cross-reactivity among different heparin preparations tested. In the presented case, history, symptoms, and results of skin testing strongly suggested an IgE-mediated allergic hypersensitivity against different heparins. Therefore, as safe alternative anticoagulants the patient could receive beneath coumarins the hirudins or direct thrombin inhibitors. Because these compounds have a completely different molecular structure compared with the heparin-polysaccharides.

  18. Voltammetric determination of heparin based on its interaction with malachite green

    Directory of Open Access Journals (Sweden)

    Xueliang Niu

    2008-08-01

    Full Text Available In this paper malachite green (MG was used as a bioprobe to determine heparin concentration by linear sweep voltammetry on the dropping mercury working electrode (DME. In Britton-Robinson (B-R buffer solution of pH 1.5, MG had a well-defined second order derivative linear sweep voltammetric reductive peak at –0.618 V (vs. SCE. After the addition of heparin into the MG solution, the reductive peak current decreased apparently without the movement of peak potential. Based on the difference of the peak current, a new voltammetric method for the determination of heparin was established. The conditions for the binding reaction and the electrochemical detection were optimized. Under the selected experimental conditions the difference of peak current was directly proportional to the concentration of heparin in the range from 0.3 to 10.0 mg/L with the linear regression equation as ∆ip″ (nA = 360.19 C (mg/L + 178.88 (n = 15, γ = 0.998 and the detection limit as 0.28 mg/L (3σ. The effects of coexisting substances such as metal ions, amino acids on the determination of heparin were investigated and the results showed that this method had good selectivity. This method was further applied to determine the heparin content in heparin sodium injection samples with satisfactory results and good recovery. The stoichiometry of the biocomplex was calculated by the electrochemical method and the binding mechanism was further discussed.

  19. Cutaneous reactions to heparin therapy: when are they caused by heparin allergy?

    Directory of Open Access Journals (Sweden)

    Giuliana Zisa

    2013-03-01

    Full Text Available Introduction: Little is known about the incidence and causes of heparin-induced skin lesions. The most commonly reported causes are delayed-type hypersensitivity reactions. We describe 3 patients who were referred to our staff between March and October 2009 for suspected heparin allergies. All were scheduled to undergo major surgery (cardiovascular or orthopedic. Materials and methods: All 3 patients reported the development of itchy, erythematous rashes a few days after the subcutaneous administration of heparin (nadroparin calcium in cases 1 and 2, unspecified in case 3. Each of them underwent a diagnostic work-up for heparin allergy, which included prick and intradermal tests with commonly used heparins and patch testing with undiluted heparins and disinfectants. Results: Patch tests with disinfectants were negative in all 3 cases. In case 2, all allergological tests were negative. In cases 1 and 3, delayed positivity emerged for nadroparin calcium and at least one other heparin tested. Intravenous and/or subcutaneous provocation testing was done with an alternative heparin which produced negative results in skin tests (heparin sodium in case 1, pentasaccharide fondaparinux in case 3. In both cases the alternative drug was tolerated. After our evaluation, all 3 patients underwent surgery with no heparin-related complications. Discussion: The presenting clinical features in these 3 cases provided no information on which reactions were likely to be allergic: all 3 patients presented with similar local delayed reaction. The allergic reactions were identified only after cutaneous testing.

  20. Preparation and characterization of microspheres of albumin-heparin conjugates

    NARCIS (Netherlands)

    Kwon, Glen S.; Bae, You Han; Kim, Sung Wan; Cremers, Harry; Cremers, H.F.M.; Feijen, Jan

    1991-01-01

    Albumin-heparin microspheres have been prepared as a new drug carrier. A soluble albumin-heparin conjugate was synthesized by forming amide bonds between human serum albumin and heparin. After purification the albumin-heparin conjugate was crosslinked in a water-in-oil emulsion to form

  1. Click-coated, heparinized, decellularized vascular grafts.

    Science.gov (United States)

    Dimitrievska, Sashka; Cai, Chao; Weyers, Amanda; Balestrini, Jenna L; Lin, Tylee; Sundaram, Sumati; Hatachi, Go; Spiegel, David A; Kyriakides, Themis R; Miao, Jianjun; Li, Guoyun; Niklason, Laura E; Linhardt, Robert J

    2015-02-01

    A novel method enabling the engineering of a dense and appropriately oriented heparin-containing layer on decellularized aortas has been developed. Amino groups of decellularized aortas were first modified to azido groups using 3-azidobenzoic acid. Azide-clickable dendrons were attached onto the azido groups through "alkyne-azide" click chemistry, affording a tenfold amplification of adhesions sites. Dendron end groups were finally decorated with end-on modified heparin chains. Heparin chains were oriented like heparan sulfate groups on native endothelial cells surface. X-ray photoelectron spectroscopy, nuclear magnetic resonance imaging, mass spectrometry and Fourier transform infrared FTIR spectroscopy were used to characterize the synthesis steps, building the final heparin layered coatings. The continuity of the heparin coating was verified using fluorescent microscopy and histological analysis. The efficacy of heparin linkage was demonstrated with factor Xa anti-thrombogenic assay and platelet adhesion studies. The results suggest that oriented heparin immobilization to decellularized aortas may improve the in vivo blood compatibility of decellularized aortas and vessels. Copyright © 2014 Acta Materialia Inc. All rights reserved.

  2. Oral heparin results in the appearance of heparin fragments in the plasma of rats

    International Nuclear Information System (INIS)

    Larsen, A.K.; Lund, D.P.; Langer, R.; Folkman, J.

    1986-01-01

    We have previously shown that angiogenesis inhibition and tumor regression can be accomplished by combinations of heparin or heparin fragments with cortisone. Oral heparin was also effective in combination with cortisone. We now show that a single oral dose of [ 35 S]heparin or [ 3 H]heparin (15,000 units/kg) results in continuous release of radioactive material into the bloodstream for at least 12 hr. This is associated with the presence of anti-factor Xa activity at a level of approximately equal to 0.1 unit/ml. The radioactive material is identified as oligo-, di-, and monosaccharides by its behavior in chromatographic systems, its possession of anti-factor Xa activity, and the effect of treatment with bacterial heparinase. The heparin fragments are extensively metabolized to fragments without anti-factor Xa activity that are readily subject to urinary excretion

  3. 77 FR 7584 - Draft Guidance for Industry on Heparin for Drug and Medical Device Use; Monitoring Crude Heparin...

    Science.gov (United States)

    2012-02-13

    ... strategies to ensure that the heparin supply chain is not contaminated with OSCS or any non- porcine origin... device manufacturers of finished products, and others to the potential risk of crude heparin...) among patients injected with heparin sodium in 2008, FDA identified the contaminant OSCS in heparin API...

  4. 78 FR 38058 - Guidance for Industry on Heparin for Drug and Medical Device Use: Monitoring Crude Heparin for...

    Science.gov (United States)

    2013-06-25

    ... public health. FDA developed this guidance to alert manufacturers to the risks of crude heparin contaminants and to recommend strategies to ensure that the heparin supply chain is not contaminated with OSCS... heparin sodium in 2008, FDA identified the contaminant OSCS in crude heparin sourced from China. FDA is...

  5. Heparin- induced thrombocytopenia (HIT: a case report of CABG patient

    Directory of Open Access Journals (Sweden)

    Alireza Jahangirifard

    2016-08-01

    Full Text Available Heparin- induced thrombocytopenia (HIT is an antibody mediated adverse effect of heparin therapy which is classified into two subtypes, HITI which is non-immune, spontaneously reversible thrombocytopenia and; HITII which is an autoimmune-mediated adverse effect of heparin therapy. In this case report, we described a 65-year old male patient with HITII after coronary artery bypass grafting.Key words: Heparin- induced thrombocytopenia, Heparin- induced thrombosis, coronary artery bypass grafting.

  6. Cationization of heparin for film applications

    Czech Academy of Sciences Publication Activity Database

    Šimkovic, I.; Mendichi, R.; Kelnar, Ivan; Filip, J.; Hricovíni, M.

    2015-01-01

    Roč. 115, 22 January (2015), s. 551-558 ISSN 0144-8617 Institutional support: RVO:61389013 Keywords : heparin * cationization * NMR Subject RIV: CD - Macromolecular Chemistry Impact factor: 4.219, year: 2015

  7. Heparin modulates the endopeptidase activity of Leishmania mexicana cysteine protease cathepsin L-Like rCPB2.8.

    Directory of Open Access Journals (Sweden)

    Wagner A S Judice

    Full Text Available Cysteine protease B is considered crucial for the survival and infectivity of the Leishmania in its human host. Several microorganism pathogens bind to the heparin-like glycosaminoglycans chains of proteoglycans at host-cell surface to promote their attachment and internalization. Here, we have investigated the influence of heparin upon Leishmania mexicana cysteine protease rCPB2.8 activity.THE DATA ANALYSIS REVEALED THAT THE PRESENCE OF HEPARIN AFFECTS ALL STEPS OF THE ENZYME REACTION: (i it decreases 3.5-fold the k 1 and 4.0-fold the k -1, (ii it affects the acyl-enzyme accumulation with pronounced decrease in k 2 (2.7-fold, and also decrease in k 3 (3.5-fold. The large values of ΔG  =  12 kJ/mol for the association and dissociation steps indicate substantial structural strains linked to the formation/dissociation of the ES complex in the presence of heparin, which underscore a conformational change that prevents the diffusion of substrate in the rCPB2.8 active site. Binding to heparin also significantly decreases the α-helix content of the rCPB2.8 and perturbs the intrinsic fluorescence emission of the enzyme. The data strongly suggest that heparin is altering the ionization of catalytic (Cys(25-S(-/(His(163-Im(+ H ion pair of the rCPB2.8. Moreover, the interaction of heparin with the N-terminal pro-region of rCPB2.8 significantly decreased its inhibitory activity against the mature enzyme.Taken together, depending on their concentration, heparin-like glycosaminoglycans can either stimulate or antagonize the activity of cysteine protease B enzymes during parasite infection, suggesting that this glycoconjugate can anchor parasite cysteine protease at host cell surface.

  8. Heparin-Functionalized chitosan/ κ-carrageenan complexes as potential scaffolds for tissue engineering

    International Nuclear Information System (INIS)

    Dofeliz, Joni L.; Rojas, Nina Rosario L.

    2015-01-01

    Cell-based approaches to tissue regeneration are playing an increasingly important role in bone and cartilage repair. This is made possible through the use of growth factors, which are signaling molecules that induce a number of effects such as cell proliferation, migration and differentiation. But problems arise as these growth factors tend to be expensive, short-lived and slow moving through the extracellular matrix, making them very inefficient in their current form of introduction. One such growth factor is basic fibroblast growth factor (bFGF). The general objective of this study is to construct heparin-functionalized chitosan/κ-carrageenan scaffolds, which when bound to basic fibroblast growth factor (bFGF), may be used in the culture of mesenchymal stem cells for differentiation into cartilage. In this study, gels of semi-interpenetrating networks (semi-IPN) of chitosan and κ-carrageenan (2:4:1 blend ration) were prepared using calcium chloride as a cross-linker. The gels were then functionalized with heparin, which is known for its growth factor binding ability, using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) as cross-linker. The functionalized gels were then reshaped into scaffold on the wells of 48-well plates through freeze-dry method. The scaffolds were found to be realatively porous with pore sizes larger than 100 μm which satisfies the requirements for cell culture. Subsequent thermogravimetric analysis shows that the scaffolds were relatively stable with a degradation temperature of 277°C. Additionally, there was no observable separation of the individual degradation temperatures of chitosan and κ-carrageenan, confirming that a single miscible phase in the form of a semi-IPN structure was created. Results of scanning electron microscopy also showed that the scaffolds were stable under 2 hours of UV sterilization. The FTIR spectra of the heparinized PEC showed characteristic absorption bands (S=O asymetric stretch) in the area of 1160

  9. Heparin octasaccharide decoy liposomes inhibit replication of multiple viruses

    Science.gov (United States)

    Hendricks, Gabriel L.; Velazquez, Lourdes; Pham, Serena; Qaisar, Natasha; Delaney, James C.; Viswanathan, Karthik; Albers, Leila; Comolli, James C.; Shriver, Zachary; Knipe, David M.; Kurt-Jones, Evelyn A.; Fygenson, Deborah K.; Trevejo, Jose M.

    2016-01-01

    Heparan sulfate (HS) is a ubiquitous glycosaminoglycan that serves as a cellular attachment site for a number of significant human pathogens, including respiratory syncytial virus (RSV), human parainfluenza virus 3 (hPIV3), and herpes simplex virus (HSV). Decoy receptors can target pathogens by binding to the receptor pocket on viral attachment proteins, acting as ‘molecular sinks’ and preventing the pathogen from binding to susceptible host cells. Decoy receptors functionalized with HS could bind to pathogens and prevent infection, so we generated decoy liposomes displaying HS-octasaccharide (HS-octa). These decoy liposomes significantly inhibited RSV, hPIV3, and HSV infectivity in vitro to a greater degree than the original HS-octa building block. The degree of inhibition correlated with the density of HS-octa displayed on the liposome surface. Decoy liposomes with HS-octa inhibited infection of viruses to a greater extent than either full-length heparin or HS-octa alone. Decoy liposomes were effective when added prior to infection or following the initial infection of cells in vitro. By targeting the well-conserved receptor-binding sites of HS-binding viruses, decoy liposomes functionalized with HS-octa are a promising therapeutic antiviral agent and illustrate the utility of the liposome delivery platform. PMID:25637710

  10. Epidermal Growth Factor and Intestinal Barrier Function

    Directory of Open Access Journals (Sweden)

    Xiaopeng Tang

    2016-01-01

    Full Text Available Epidermal growth factor (EGF is a 53-amino acid peptide that plays an important role in regulating cell growth, survival, migration, apoptosis, proliferation, and differentiation. In addition, EGF has been established to be an effective intestinal regulator helping to protect intestinal barrier integrity, which was essential for the absorption of nutrients and health in humans and animals. Several researches have demonstrated that EGF via binding to the EGF receptor and subsequent activation of Ras/MAPK, PI3K/AKT, PLC-γ/PKC, and STATS signal pathways regulates intestinal barrier function. In this review, the relationship between epidermal growth factor and intestinal development and intestinal barrier is described, to provide a better understanding of the effects of EGF on intestine development and health.

  11. DEGRADATION AND INTRAHEPATIC COMPATIBILITY OF ALBUMIN-HEPARIN CONJUGATE MICROSPHERES

    NARCIS (Netherlands)

    CREMERS, HFM; WOLF, RFE; BLAAUW, EH; SCHAKENRAAD, JM; LAM, KH; NIEUWENHUIS, P; VERRIJK, R; KWON, G; BAE, YH; KIM, SW; FEIJEN, J

    The in vitro degradation properties of glutaraldehyde cross-linked albumin and albumin-heparin conjugate microspheres (AMS and AHCMS respectively) were evaluated using light microscopy, turbidity measurements and heparin release determinations, showing that the microspheres are degraded by

  12. Endogenous heparin levels in the controlled asthmatic patient ...

    African Journals Online (AJOL)

    Background. Since heparin possesses anti-inflammatory properties, it is hypothesised that asthmatic patients have decreased levels of circulating heparin compared with healthy individuals. Design. We compared endogenous heparin levels in controlled asthmatic patients (53 adults) from the Asthma Clinic at ...

  13. Heparin increases food intake through AgRP neurons

    Science.gov (United States)

    Although the widely used anticoagulant drug heparin has been shown to have many other biological functions independent of its anticoagulant role, its effects on energy homeostasis are unknown. Here, we demonstrate that heparin level is negatively associated with nutritional states and that heparin t...

  14. Characterization of heparin aerosols generated in jet and ultrasonic nebulizers

    DEFF Research Database (Denmark)

    Bendstrup, K.E.; Newhouse, M.T.; Pedersen, Ole Finn

    1999-01-01

    Inhaled heparin has been used for asthma treatment, but results have been inconsistent, probably due to highly varying lung doses. We determined the output per unit time and the particle size distributions of sodium heparin, calcium heparin, and low molecular weight (LMW) heparin formulations in ...... on the exhalation filter, and 15,000 IU was captured on the inhalation filter (inhaled mass). This corresponds to a respirable mass of 10,000 IU of heparin with a high probability of reaching the lower respiratory tract in normal healthy adults....

  15. Antiproliferative heparin (glycosaminoglycans) isolated from giant ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-18

    May 18, 2009 ... source of these sulfated polysaccharides (Nader and. Dietrich, 1989) and it often corresponds up to 90% of the total GAG content of these organisms. Heparin and heap- rin-like substances have a wide range of important biolo- gical activities including inhibition of pulmonary artery smooth muscle cell ...

  16. Biological distribution of 51Cr-heparin

    International Nuclear Information System (INIS)

    Almeida, M.A.T.M. de.

    1979-01-01

    The kinetics of heparin in normal Wistar rats using the radioactive tracer 51 Cr, has been studied. The labeled and purified 51 Cr-heparin was injected into rats intravenously and by intraperitoneal injection. In measuring the radioactivity of organs it was possible to conclude that the tissues rich in mast cells, liver and spleen, were found to take up the greater amounts of heparin. The curve that represents the logarithm of the concentration of heparin versus time is biexponential. The half-lives of the two exponential were determined. The volume of distribution, the rate constant and the renal clearance were determined by the values of the plasma levels and urinary excretions. The biological half-time, the turnover rate and the turnover time were determined by measuring the residual radioactivity of the total body and urinary excretions. With the data obtained from the mentioned experiments a compartmental model was performed in which the plasma is the central compartment for the distribution of the drug, exchanging with another extraplasmatic compartment and finally the drug being stored in reticulo endothelial system cells. (Author) [pt

  17. [Progress in epidermal stem cells].

    Science.gov (United States)

    Wang, Li-Juan; Wang, You-Liang; Yang, Xiao

    2010-03-01

    Mammalian skin epidermis contains different epidermal stem cell pools which contribute to the homeostasis and repair of skin epithelium. Epidermal stem cells possess two essential features common to all stem cells: self-renewal and differentiation. Disturbing the balance between self-renewal and differentiation of epidermal stem cell often causes tumors or other skin diseases. Epidermal stem cell niches provide a special microenvironment that maintains a balance of stem cell quiescence and activity. This review primarily concentrates on the following points of the epidermal stem cells: the existing evidences, the self-renewal and differentiation, the division pattern, the signal pathways regulating self-renewal and differentiation, and the microenvironment (niche) and macroenvironment maintaining the homeostasis of stem cells.

  18. Surface biomimetic modification with laminin-loaded heparin/poly-L-lysine nanoparticles for improving the biocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Tao, E-mail: 11140021@hyit.edu.cn [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai' an (China); Hu, Youdong [Department of Geriatrics, The Affiliated Huai' an Hospital of Xuzhou Medical College, Huai' an (China); Tan, Jianying [Key Lab. of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Liu, Shihui [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai' an (China); Chen, Junying [Key Lab. of Advanced Technology for Materials of Chinese Education Ministry, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu (China); Guo, Xin; Pan, Changjiang [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai' an (China); Li, Xia, E-mail: xial_li@qq.com [Department of Geriatrics, The Affiliated Huai' an Hospital of Xuzhou Medical College, Huai' an (China)

    2017-02-01

    Late thrombus and restenosis caused by delayed endothelialization and insufficient biocompatibility of polymer coating continue to be the greatest limitations of drug-eluting stents. In this study, based on the specific structure of vascular basement membrane, a novel biomimetic nano-coating was constructed by incorporating laminin into electrostatic-assembled heparin/poly-L-lysine nanoparticles. Alteration of heparin and poly-L-lysine concentration ratio in a certain range has no significantly influence nanoparticle size, uniformity and stability, but may affect the chemical property and subsequently the binding efficiency to dopamine-coated titanium surface. By use of this feature, four different nanoparticles were synthesized and immobilized on titanium surface for creating gradient nanoparticle binding density. According to in vitro biocompatibility evaluation, the nanoparticle modified surfaces were found to effectively block coagulation pathway and reduce thrombosis formation. Moreover, NP10L and NP15L modified surface with relatively low heparin exposing density (4.9 to 7.1 μg/cm2) showed beneficial effect in selective promoting EPCs and ECs proliferation, as well as stimulating cell migration and NO synthesis. - Highlights: • A novel laminin-loaded anticoagulant nanoparticle was prepared and used for titanium surface modification. • The nanoparticle binding density was adjustable by alteration the concentration ratio of heparin and poly-L-lysine. • In a certain range of NPs density, the surface was found to selectively direct platelet and vascular cells behavior.

  19. Surface biomimetic modification with laminin-loaded heparin/poly-L-lysine nanoparticles for improving the biocompatibility

    International Nuclear Information System (INIS)

    Liu, Tao; Hu, Youdong; Tan, Jianying; Liu, Shihui; Chen, Junying; Guo, Xin; Pan, Changjiang; Li, Xia

    2017-01-01

    Late thrombus and restenosis caused by delayed endothelialization and insufficient biocompatibility of polymer coating continue to be the greatest limitations of drug-eluting stents. In this study, based on the specific structure of vascular basement membrane, a novel biomimetic nano-coating was constructed by incorporating laminin into electrostatic-assembled heparin/poly-L-lysine nanoparticles. Alteration of heparin and poly-L-lysine concentration ratio in a certain range has no significantly influence nanoparticle size, uniformity and stability, but may affect the chemical property and subsequently the binding efficiency to dopamine-coated titanium surface. By use of this feature, four different nanoparticles were synthesized and immobilized on titanium surface for creating gradient nanoparticle binding density. According to in vitro biocompatibility evaluation, the nanoparticle modified surfaces were found to effectively block coagulation pathway and reduce thrombosis formation. Moreover, NP10L and NP15L modified surface with relatively low heparin exposing density (4.9 to 7.1 μg/cm2) showed beneficial effect in selective promoting EPCs and ECs proliferation, as well as stimulating cell migration and NO synthesis. - Highlights: • A novel laminin-loaded anticoagulant nanoparticle was prepared and used for titanium surface modification. • The nanoparticle binding density was adjustable by alteration the concentration ratio of heparin and poly-L-lysine. • In a certain range of NPs density, the surface was found to selectively direct platelet and vascular cells behavior.

  20. Influence of spacer length on heparin coupling efficiency and fibrinogen adsorption of modified titanium surfaces

    Directory of Open Access Journals (Sweden)

    Gbureck Uwe

    2007-07-01

    Full Text Available Abstract Background Chemical bonding of the drug onto surfaces by means of spacer molecules is accompanied with a reduction of the biological activity of the drug due to a constricted mobility since normally only short spacer molecule like aminopropyltrimethoxysilane (APMS are used for drug coupling. This work aimed to study covalent attachment of heparin to titanium(oxide surfaces by varying the length of the silane coupling agent, which should affect the biological potency of the drug due to a higher mobility with longer spacer chains. Methods Covalent attachment of heparin to titanium metal and TiO2 powder was carried out using the coupling agents 3-(Trimethoxysilyl-propylamine (APMS, N- [3-(Trimethoxysilylpropyl]ethylenediamine (Diamino-APMS and N1- [3-(Trimethoxy-silyl-propyl]diethylenetriamine (Triamino-APMS. The amount of bound coupling agent and heparin was quantified photometrically by the ninhydrin reaction and the tolidine-blue test. The biological potency of heparin was determined photometrically by the chromogenic substrate Chromozym TH and fibrinogen adsorption to the modified surfaces was researched using the QCM-D (Quartz Crystal Microbalance with Dissipation Monitoring technique. Results Zeta-potential measurements confirmed the successful coupling reaction; the potential of the unmodified anatase surface (approx. -26 mV shifted into the positive range (> + 40 mV after silanisation. Binding of heparin results in a strongly negatively charged surface with zeta-potentials of approx. -39 mV. The retaining biological activity of heparin was highest for the spacer molecule Triamino-APMS. QCM-D measurements showed a lower viscosity for adsorbed fibrinogen films on heparinised surfaces by means of Triamino-APMS. Conclusion The remaining activity of heparin was found to be highest for the covalent attachment with Triamino-APMS as coupling agent due to the long chain of this spacer molecule and therefore the highest mobility of the drug

  1. Heparin molecularly imprinted polymer thin flm on gold electrode by plasma-induced graft polymerization for label-free biosensor.

    Science.gov (United States)

    Orihara, Kouhei; Hikichi, Atsushi; Arita, Tomohiko; Muguruma, Hitoshi; Yoshimi, Yasuo

    2018-03-20

    Heparin, a highly sulfated glycosaminoglycan, is an important biomaterial having biological and therapeutic functionalities such as anticoagulation, regeneration, and protein stabilization. This study addresses a label-free quartz crystal microbalance (QCM) biosensor for heparin detection based on a macromolecularly imprinted polymer (MIP) as an artificial recognition element. We demonstrate the novel strategy for MIP in the form of thin film on a gold (Au) electrode with the plasma-induced graft polymerization (PIP) technique. The procedure of PIP is as follows: (i) Hexamethyldisiloxane plasma-polymerized thin film (PPF) as a pre-coating scaffold of active species for PIP (post-polymerization) is deposited on an Au electrode. (ii) The PPF/Au electrode is soaked in an water solution containing heparin (template), (2-(methacryloxy)-ethyl)trimethylammonium chloride acrylamide (functional monomer), acrylamide, and N,N-methylenebisacrylamide (crosslinker). Double bonds of monomer and crosslinker attacked by residually active species in pre-coating PPF cause radical chain reaction. Consequently, a growing polymer network of 20 nm thickness of PIP-MIP thin film is formed and grafted on the PPF/Au surface. (iii) The PIP-MIP/PPF/Au is washed by sodium chloride solution so as to remove the template. Non-imprinted polymer (NIP) is carried out like the same procedure without a template. The AFM, XPS, and QCM measurements show that the PIP process facilitates macromolecularly surface imprinting of template heparin where the template is easily removed and is rapidly rebound to PIP-MIP without a diffusional barrier. The heparin-PIP-MIP specifically binds to heparin compared with heparin analog chondroitin sulfate C (selective factor: 4.0) and a detectable range of heparin in the presence of CS (0.1 wt%) was 0.001-0.1 wt%. The PIP-NIP does not show selectivity between them. The evaluated binding kinetics are association (k a  = 350 ± 100 M -1  s -1

  2. Sensitive detection of oversulfated chondroitin sulfate in heparin sodium or crude heparin with a colorimetric microplate based assay.

    Science.gov (United States)

    Sommers, Cynthia D; Mans, Daniel J; Mecker, Laura C; Keire, David A

    2011-05-01

    In this work we describe a 96-well microplate assay for oversulfated chondroitin sulfate A (OSCS) in heparin, based on a water-soluble cationic polythiophene polymer (3-(2-(N-(N'-methylimidazole))ethoxy)-4-methylthiophene (LPTP)) and heparinase digestion of heparin. The assay takes advantage of several unique properties of heparin, OSCS, and LPTP, including OSCS inhibition of heparinase I and II activity, the molecular weight dependence of heparin-LPTP spectral shifts, and the distinct association of heparin fragments and OSCS to LPTP. These factors combine to enable detection of the presence of 0.003% w/w spiked OSCS in 10 μg of heparin sodium active pharmaceutical ingredient (API) using a plate reader and with visual detection to 0.1% levels. The same detection limit for OSCS was observed in the presence of 10% levels of dermatan sulfate (DS) or chondroitin sulfate A (CSA) impurities. In addition, we surveyed a selection of crude heparin samples received by the agency in 2008 and 2009 to determine average and extreme DS, CSA, and galactosamine weight percent levels. In the presence of these impurities and the variable heparin content in the crude heparin samples, spiked OSCS was reliably detected to the 0.1% w/w level using a plate reader. Finally, authentically OSCS contaminated heparin sodium API and crude samples were distinguished visually by color from control samples using the LPTP/heparinase test.

  3. Increased synthesis of heparin affin regulatory peptide in the perforant path lesioned mouse hippocampal formation

    DEFF Research Database (Denmark)

    Poulsen, F R; Lagord, C; Courty, J

    2000-01-01

    Heparin affin regulatory peptide (HARP), also known as pleiotrophin or heparin-binding growth-associated molecule, is a developmentally regulated extracellular matrix protein that induces cell proliferation and promotes neurite outgrowth in vitro as well as pre- and postsynaptic developmental...... differentiation in vivo. Here we have investigated the expression of HARP mRNA and protein in the perforant path lesioned C57B1/6 mouse hippocampal formation from 1 to 35 days after surgery. This type of lesion induces a dense anterograde and terminal axonal degeneration, activation of glial cells, and reactive...... axonal sprouting within the perforant path zones of the fascia dentata and hippocampus as well as axotomy-induced retrograde neuronal degeneration in the entorhinal cortex. Analysis of sham- and unoperated control mice showed that HARP mRNA is expressed in neurons and white and gray matter glial cells...

  4. Electrophoresis for the analysis of heparin purity and quality.

    Science.gov (United States)

    Volpi, Nicola; Maccari, Francesca; Suwan, Jiraporn; Linhardt, Robert J

    2012-06-01

    The adulteration of raw heparin with oversulfated chondroitin sulfate (OSCS) in 2007-2008 produced a global crisis resulting in extensive revisions to the pharmacopeia monographs and prompting the FDA to recommend the development of additional methods for the analysis of heparin purity. As a consequence, a wide variety of innovative analytical approaches have been developed for the quality assurance and purity of unfractionated and low-molecular-weight heparins. This review discusses recent developments in electrophoresis techniques available for the sensitive separation, detection, and partial structural characterization of heparin contaminants. In particular, this review summarizes recent publications on heparin quality and related impurity analysis using electrophoretic separations such as capillary electrophoresis (CE) of intact polysaccharides and hexosamines derived from their acidic hydrolysis, and polyacrylamide gel electrophoresis (PAGE) for the separation of heparin samples without and in the presence of its relatively specific depolymerization process with nitrous acid treatment. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Does ′heparin-induced thrombocytopenia′ hit our minds?

    Directory of Open Access Journals (Sweden)

    Arun R Thangavel

    2016-01-01

    Full Text Available Unfractionated heparin is a widely used drug to prevent deep vein thrombosis and pulmonary emboli in patients at risk. With the advent of newer anticoagulants having lesser side effects, its use has diminished but not out of service. Here, we report a case of deep venous thrombosis, in a patient on prophylactic dose of heparin, which was later found to be a manifestation of heparin-induced thrombocytopenia (HIT. Thrombosis in the presence of heparin prophylaxis should be considered as HIT rather than a failure of anticoagulation.

  6. Immunomodulating effects of heparin on human B cell proliferation

    International Nuclear Information System (INIS)

    Wasik, Maria; Stepien-Sopniewska, Barbara; Gorski, Andrzej

    1993-01-01

    Recent data indicate that heparin may act as an immunomodulator. In this paper we have analyzed the effect of this agent on human B cell proliferation ''in vitro'' induced by ''S. aureus'' Cowan. The action of heparin is complex, but there was a trend for inhibition of B cell responses obtained from defibrinated but not heparinized blood samples. This suggest that heparin interacts with platelet products (growth factors, cytokines) and the results of such interactions determine the final effect. (author). 6 refs, 4 figs

  7. D-fructose-binding proteins in bull seminal plasma: Isolation and characterization

    Czech Academy of Sciences Publication Activity Database

    Liberda, J.; Kraus, Marek; Ryšlavá, H.; Vlasáková, M.; Jonáková, Věra; Tichá, M.

    2001-01-01

    Roč. 47, č. 4 (2001), s. 113-119 ISSN 0015-5500 R&D Projects: GA ČR GA303/99/0357; GA ČR GV524/96/K162 Institutional research plan: CEZ:AV0Z5052915 Keywords : bull seminal plasma * non-heparin-binding and heparin-binding proteins * D-fructose-binding proteins Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.519, year: 2001

  8. Effect of buffer at nanoscale molecular recognition interfaces - electrostatic binding of biological polyanions.

    Science.gov (United States)

    Rodrigo, Ana C; Laurini, Erik; Vieira, Vânia M P; Pricl, Sabrina; Smith, David K

    2017-10-19

    We investigate the impact of an over-looked component on molecular recognition in water-buffer. The binding of a cationic dye to biological polyanion heparin is shown by isothermal calorimetry to depend on buffer (Tris-HCl > HEPES > PBS). The heparin binding of self-assembled multivalent (SAMul) cationic micelles is even more buffer dependent. Multivalent electrostatic molecular recognition is buffer dependent as a result of competitive interactions between the cationic binding interface and anions present in the buffer.

  9. Toxic epidermal necrolysis.

    Science.gov (United States)

    Pereira, Frederick A; Mudgil, Adarsh Vijay; Rosmarin, David M

    2007-02-01

    Toxic epidermal necrolysis (TEN) is an unpredictable, life-threatening drug reaction associated with a 30% mortality. Massive keratinocyte apoptosis is the hallmark of TEN. Cytotoxic T lymphocytes appear to be the main effector cells and there is experimental evidence for involvement of both the Fas-Fas ligand and perforin/granzyme pathways. Optimal treatment for these patients remains to be clarified. Discontinuation of the offending drug and prompt referral to a burn unit are generally agreed upon steps. Beyond that, however, considerable controversy exists. Evidence both pro and con exists for the use of IVIG, systemic corticosteroid, and other measures. There is also evidence suggesting that combination therapies may be of value. All the clinical data, however, is anecdotal or based on observational or retrospective studies. Definitive answers are not yet available. Given the rarity of TEN and the large number of patients required for a study to be statistically meaningful, placebo controlled trials are logistically difficult to accomplish. The absence of an animal model further hampers research into this condition. This article reviews recent data concerning clinical presentation, pathogenesis and treatment of TEN. At the conclusion of this learning activity, participants should have acquired a more comprehensive knowledge of our current understanding of the classification, clinical presentation, etiology, pathophysiology, prognosis, and treatment of TEN.

  10. Structural and functional characterization of the interaction between cyclophilin B and a heparin-derived oligosaccharide.

    Science.gov (United States)

    Hanoulle, Xavier; Melchior, Aurélie; Sibille, Nathalie; Parent, Benjamin; Denys, Agnès; Wieruszeski, Jean-Michel; Horvath, Dragos; Allain, Fabrice; Lippens, Guy; Landrieu, Isabelle

    2007-11-23

    The chemotaxis and integrin-mediated adhesion of T lymphocytes triggered by secreted cyclophilin B (CypB) depend on interactions with both cell surface heparan sulfate proteoglycans (HSPG) and the extracellular domain of the CD147 membrane receptor. Here, we use NMR spectroscopy to characterize the interaction of CypB with heparin-derived oligosaccharides. Chemical shift perturbation experiments allowed the precise definition of the heparan sulfate (HS) binding site of CypB. The N-terminal extremity of CypB, which contains a consensus sequence for heparin-binding proteins was modeled on the basis of our experimental NMR data. Because the HS binding site extends toward the CypB catalytic pocket, we measured its peptidyl-prolyl cis-trans isomerase (PPIase) activity in the absence or presence of a HS oligosaccharide toward a CD147-derived peptide. We report the first direct evidence that CypB is enzymatically active on CD147, as it is able to accelerate the cis/trans isomerization of the Asp(179)-Pro(180) bond in a CD147-derived peptide. However, HS binding has no significant influence on this PPIase activity. We thus conclude that the glycanic moiety of HSPG serves as anchor for CypB at the cell surface, and that the signal could be transduced by CypB via its PPIase activity toward CD147.

  11. Naked eye detection of infertility based on sperm protamine-induced aggregation of heparin gold nanoparticles.

    Science.gov (United States)

    Vidya, Raj; Saji, Alex

    2018-05-01

    The development of an easy to use, one-pot, environmentally friendly, non-invasive and label-free colorimetric probe for the determination of semen protamines, the biochemical marker of male fertility, using heparin gold nanoparticles (HAuNPs) is presented. The affinity of HAuNPs for protamines was due to the electrostatic interactions between polycationic protamine and polyanionic heparin. The binding of HAuNPs to protamine was characterized by variation in the plasmon absorption spectra followed by a visibly observable colour change of the solution from red to blue. We observed a red shift in the plasmon peak and the method exhibited linearity in the range of 10-70 ng/mL with a detection limit of 5 ng/mL, which is much lower than that reported for colorimetric sensors of protamine. The colour change and the variation in the absorbance of HAuNPs were highly specific for protamines in the presence of different interfering compounds and the method was successfully applied for determining protamine in real samples of semen and serum. Rather than a quantitative estimation, it seems that the method provides a quick screening between a large array of positive and negative samples and, moreover, it maintains the privacy of the user. The method appears to be simple and would be very useful in third-world countries where high-tech diagnostic aids are inaccessible to the majority of the population. Graphical Abstract Heparin gold nanoparticles aided visual detection of infertility.

  12. SPECIFIC ASPECTS OF INTERACTION OF PLATELETS WITH THE HEPARINIZED MATERIALS

    Directory of Open Access Journals (Sweden)

    E.A. Nemets

    2012-01-01

    Full Text Available Comparative analysis of anticoagulant nature on medical materials testing was done. It was found that change of citrate by heparin is accompanied by significant changes in platelet adhesion and activation. This results allowed us to arrive at a conclusion about reasonability of heparin usage as anticoagulant in in vitro testing. 

  13. 99m Tc-labeled heparin test in orthopaedic surgery

    International Nuclear Information System (INIS)

    Bouvier, J.F.; Lafon, J.C.; Colin, M.; Chatelut, J.; Beaubatie, F.

    1983-01-01

    99m Tc-labeled heparin test was performed for early detection of phlebitis or pulmonary embolism after orthopaedic prothesis. Heparinic treatment and surgery per se were demonstrated to have no effect on the results. If this test demonstrates a statistical difference for pathologic patients, it is of greater value to consider ratio between rates before and after intervention [fr

  14. Citrate Anticoagulation for CRRT in Children: Comparison with Heparin

    Directory of Open Access Journals (Sweden)

    Sara Nicole Fernández

    2014-01-01

    Full Text Available Regional anticoagulation with citrate is an alternative to heparin in continuous renal replacement therapies, which may prolong circuit lifetime and decrease hemorrhagic complications. A retrospective comparative cohort study based on a prospective observational registry was conducted including critically ill children undergoing CRRT. Efficacy, measured as circuit survival, and secondary effects of heparin and citrate were compared. 12 patients on CRRT with citrate anticoagulation and 24 patients with heparin anticoagulation were analyzed. Median citrate dose was 2.6 mmol/L. Median calcium dose was 0.16 mEq/kg/h. Median heparin dose was 15 UI/kg/h. Median circuit survival was 48 hours with citrate and 31 hours with heparin (P=0.028. 66.6% of patients treated with citrate developed mild metabolic alkalosis, which was directly related to citrate dose. There were no cases of citrate intoxication: median total calcium/ionic calcium index (CaT/I of 2.16 and a maximum CaT/I of 2.33, without metabolic acidosis. In the citrate group, 45.5% of patients developed hypochloremia and 27.3% hypomagnesemia. In the heparin group, 27.8% developed hypophosphatemia. Three patients were moved from heparin to citrate to control postoperatory bleeding. In conclusion citrate is a safe and effective anticoagulation method for CRRT in children and it achieves longer circuit survival than heparin.

  15. Heparin release from thermosensitive polymer coatings: in vivo studies

    NARCIS (Netherlands)

    Gutowska, Anna; Bae, You Han; Jacobs, Harvey; Mohammad, Fazal; Mix, Donald; Feijen, Jan; Kim, Sung Wan

    1995-01-01

    Biomer/poly(N-isopropylacrylamide)/[poly(NiPAAm)] thermosensitive polymer blends were prepared and their application as heparin-releasing polymer coatings for the prevention of surface-induced thrombosis was examined. The advantage of using poly(NiPAAm)-based coatings as heparin-releasing polymers

  16. Heparin-induced thrombocytopenia: real-world issues.

    Science.gov (United States)

    Linkins, Lori-Ann; Warkentin, Theodore E

    2011-09-01

    Heparin-induced thrombocytopenia (HIT) is a prothrombotic drug reaction caused by platelet-activating antibodies. HIT sera often activate platelets without needing heparin-such heparin-"independent" platelet activation can be associated with HIT beginning or worsening despite stopping heparin ("delayed-onset HIT"). We address important issues in HIT diagnosis and therapy, using a recent cohort of HIT patients to illustrate influences of heparin type; triggers for HIT investigation; serological features of heparin-independent platelet activation; and treatment. In our cohort of recent HIT cases ( N = 13), low-molecular-weight heparin (dalteparin) was a common causative agent ( N = 8, 62%); most patients were diagnosed after HIT-thrombosis had occurred; and danaparoid was the most frequently selected treatment. Heparin-independent platelet activation was common (7/13 [54%]) and predicted slower platelet count recovery (>1 week) among evaluable patients (5/5 vs 1/6; P = 0.015). In our experience with argatroban-treated patients, HIT-associated consumptive coagulopathy confounds anticoagulant monitoring. Our observations provide guidance on practical aspects of HIT diagnosis and management. Thieme Medical Publishers.

  17. Anticoagulant effect of low molecular weight heparin on central ...

    African Journals Online (AJOL)

    Purpose: To analyse the effect of low molecular weight heparin on venous catheters in haemodialysis patients. Methods: This study included 140 eligible patients who were randomly and evenly divided into two groups, viz, a study group that received low molecular weight heparin and a control group that received ...

  18. Epidermal growth factor receptor (EGFR) and EGFR mutations, function and possible role in clinical trials

    DEFF Research Database (Denmark)

    Voldborg, B R; Damstrup, L; Spang-Thomsen, M

    1997-01-01

    The epidermal growth factor receptor (EGFR) is a growth factor receptor that induces cell differentiation and proliferation upon activation through the binding of one of its ligands. The receptor is located at the cell surface, where the binding of a ligand activates a tyrosine kinase in the intr...... aspects of therapeutic targeting of EGFR....

  19. Use of heparin in the investigation of obscure gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Mernagh, J.R.; O'Donovan, N.; Somers, S.; Gill, G.; Sridhar, S.

    2001-01-01

    To determine if the administration of heparin improves the predictive value of angiography in the investigation of obscure gastrointestinal (GI) bleeding. 18 patients with a history of chronic GI bleeding were investigated with angiography. For 6 patients, the cause of GI bleeding was established with angiography; the 12 patients who had negative results were given heparin for 24 h and were reassessed with angiography. After heparin administration, the source of GI bleeding was determined with angiography for 6 of the remaining 12 patients. Thus, heparinization increased diagnostic yield from 33% (6 of 18) to 67% (12 of 18). No significant complications, such as uncontrolled GI bleeding, occurred. Heparinization improves the diagnostic yield of angiography when obscure GI bleeding is being investigated. (author)

  20. Polyguluronate sulfate and its oligosaccharides but not heparin promotes FGF19/FGFR1c signaling

    Science.gov (United States)

    Lan, Ying; Zeng, Xuan; Guo, Zhihua; Zeng, Pengjiao; Hao, Cui; Zhao, Xia; Yu, Guangli; Zhang, Lijuan

    2017-06-01

    Fibroblast growth factor 19(FGF19) functions as a hormone by affecting glucose metabolism. FGF19 improves glucose tolerance when overexpressed in mice with impaired glucose tolerance or diabetes. A functional cellular FGF19 receptor consists of FGF receptor (FGFR) and glycosaminoglycan complexed with either α Klotho or β Klotho. Interestingly, in mice with diet-induced diabetes, a single injection of FGF1 is enough to restore blood sugar levels to a healthy range. FGF1 binds heparin with high affinity whereas FGF19 does not, indicating that polysaccharides other than heparin might enhance FGF19/FGFR signaling. Using a FGFs/FGFR1c signaling-dependent BaF3 cell proliferation assay, we discovered that polyguluronate sulfate (PGS) and its oligosaccharides, PGS12 and PGS25, but not polyguluronate (PG), a natural marine polysaccharide, enhanced FGF19/FGFR1c signaling better than that of heparin based on 3H-thymidine incorporation. Interestingly, PGS6, PGS8, PGS10, PGS12, PGS25, and PGS, but not PG, had comparable FGF1/FGFR1c signal-stimulating activity compared to that of heparin. These results indicated that PGS and its oligosaccharides were excellent FGF1/FGFR1c and FGF19/FGFR1c signaling enhancers at cellular level. Since the inexpensive PGS and PGS oligosaccharides can be absorbed through oral route, these seaweed-derived compounds merit further investigation as novel agents for the treatment of type 2 diabetes through enhancing FGF1/FGFR1c and FGF19/FGFR1c signaling in future.

  1. Printed microfluidic filter for heparinized blood.

    Science.gov (United States)

    Bilatto, Stanley E R; Adly, Nouran Y; Correa, Daniel S; Wolfrum, Bernhard; Offenhäusser, Andreas; Yakushenko, Alexey

    2017-05-01

    A simple lab-on-a-chip method for blood plasma separation was developed by combining stereolithographic 3D printing with inkjet printing, creating a completely sealed microfluidic device. In some approaches, one dilutes the blood sample before separation, reducing the concentration of a target analyte and increasing a contamination risk. In this work, a single drop (8  μ l) of heparinized whole blood could be efficiently filtered using a capillary effect without any external driving forces and without dilution. The blood storage in heparin tubes during 24 h at 4 °C initiated the formation of small crystals that formed auto-filtration structures in the sample upon entering the 3D-printed device, with pores smaller than the red blood cells, separating plasma from the cellular content. The total filtration process took less than 10 s. The presented printed plasma filtration microfluidics fabricated with a rapid prototyping approach is a miniaturized, fast and easy-to-operate device that can be integrated into healthcare/portable systems for point-of-care diagnostics.

  2. AUTOIMMUNE EPIDERMAL BLISTERING DISEASES

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2013-11-01

    Full Text Available Autoimmune bullous skin diseases (ABDs are uncommon, potentially fatal diseases of skin and mucous membranes which are associated with deposits of autoantibodies and complement against distinct molecules of the epidermis and dermal/epidermal basement membrane zone (BMZ. These autoantibodies lead to a loss in skin molecular integrity, which manifests clinically as formation of blisters or erosions. In pemphigus vulgaris, loss of adhesion occurs within the epidermis. The pioneering work of Ernst H. Beutner, Ph.D. and Robert E. Jordon, M.D. confirmed the autoimmune nature of these diseases. Walter F. Lever, M.D. contributed significantly to our understanding of the histopathologic features of these diseases. Walter Lever, M.D. and Ken Hashimoto, M.D. contributed electron microscopic studies of these diseases, especially in pemphigus vulgaris and bullous pemphigoid. In bullous pemphigoid (BP, linear IgA bullous dermatosis, epidermolysis bullosa acquisita (EBA and dermatitis herpetiformis (DH, loss of adhesion takes place within or underneath the BMZ. Classic EBA demonstrates extensive skin fragility; DH is commonly associated with gluten-sensitive enteropathy, and manifests clinically with pruritic papulovesicles on the extensor surfaces of the extremities and the lumbosacral area. The clinical spectrum of bullous pemphigoid includes tense blisters, urticarial plaques, and prurigo-like eczematous lesions. Pemphigoid gestationis mostly occurs during the last trimester of pregnancy, and mucous membrane pemphigoid primarily involves the oral mucosa and conjunctivae and leads to scarring. Linear IgA bullous dermatosis manifests with tense blisters in a „cluster of jewels”-like pattern in childhood (chronic bullous disease of childhood and is more clinically heterogeneous in adulthood. Many of the autoantigens in these disorders are known and have been well characterized. ABDs may be influenced by both genetic and exogenous factors. The diagnoses of

  3. Construction of mussel-inspired coating via the direct reaction of catechol and polyethyleneimine for efficient heparin immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yujie [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Luo, Rifang, E-mail: lrifang@126.com [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Shen, Fangyu; Tang, Linlin [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Wang, Jin, E-mail: jinxxwang@263.net [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Huang, Nan [School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); The Institute of Biomaterials and Surface Engineering, Southwest Jiaotong University, Chengdu 610031 (China)

    2015-02-15

    Highlights: • Catechol (CA) and PEI copolymerization was a mimetic and dopamine-like coating method. • CA/PEI film provided amine groups and was effective in heparin immobilization. • CA/PEI coating could inhibit smooth muscle cell proliferation. • CA/PEI coating did not show any significant cytotoxicity to endothelial cell. - Abstract: Dopamine could self-polymerize to form the coating on various substrates and the co-existence of catechols and amines was crucial in performing such polymerization process. In this work, a mimetic approach of coating formation was carried out based on the co-polymerization of catechol (CA) and polyethyleneimine (PEI). Mussel-inspired CA/PEI coating was deposited on 316L stainless steel (SS). Fourier transform infrared spectra (FTIR) and X-ray photoelectron spectroscopy (XPS) demonstrated the successful coating formation. QCM measurement showed good affinity of heparin immobilization on CA/PEI coating surface ascribed to the amine groups. Herein, vascular cell-material interactions like endothelial cells (ECs) and smooth muscle cells (SMCs) were also investigated. Interestingly, CA/PEI and heparin modified coatings presented no cytotoxicity to ECs, however to a certain extent, decreased SMCs proliferation. Moreover, heparin-binding surface presented significant anti-platelet adhesion and activation properties. These results effectively suggested that the mussel-inspired CA/PEI coating might be promising when served as a platform for biomolecule immobilization.

  4. Bioinspired Heparin Nanosponge Prepared by Photo-crosslinking for Controlled Release of Growth Factors

    DEFF Research Database (Denmark)

    Choi, Won Il; Sahu, Abhishek; Vilos, Cristian

    2017-01-01

    to overcome these limitations. Herein, we have developed a thermosensitive heparin nanosponge (Hep-NS) by a one step photopolymerization reaction between diacrylated pluronic and thiolated heparin molecules. The amount of heparin in Hep-NS was precisely controlled by varying the heparin amount in the reaction...

  5. Current Trends in Heparin Use During Arterial Vascular Interventional Radiology

    International Nuclear Information System (INIS)

    Durran, Alexandra C.; Watts, Christopher

    2012-01-01

    Purpose: This study was designed to assess the current use of heparinized saline and bolus doses of heparin in non-neurological interventional radiology and to determine whether consensus could be reached to produce guidance for heparin use during arterial vascular intervention. Methods: An interactive electronic questionnaire was distributed to members of the British Society of Interventional Radiology regarding their current practice in the use, dosage, and timing of heparin boluses and heparinized flushing solutions.ResultsA total of 108 completed questionnaires were received. More than 80% of respondents used heparinized saline with varying concentrations; the most prevalent was 1,000 IU/l (international units of heparin per liter) and 5,000 IU/l. Fifty-one percent of interventionalists use 3,000 IU as their standard bolus dose; however, the respondents were split regarding the timing of bolus dose with ∼60% administering it after arterial access is obtained and 40% after crossing the lesion. There was no consensus on altering dose according to body weight, and only 4% monitored clotting parameters. Conclusions: There seems to be some coherence among practicing interventionalists regarding heparin administration. We hypothesize that heparinized saline should be used at a recognized standard concentration of 1,000 IU/l as a flushing concentration in all arterial vascular interventions and that 3,000 IU bolus is considered the standard dose for straightforward therapeutic procedures and 5000 IU for complex, crural, and endovascular aneurysm repair work. The bolus should be given after arterial access is obtained to allow time for optimal anticoagulation to be achieved by the time of active intervention and stenting. Further research into clotting abnormalities following such interventional procedures would be an interesting quantifiable follow-up to this initial survey of opinions and practice.

  6. Prophylaxis of postoperative thromboembolism with low molecular weight heparins

    DEFF Research Database (Denmark)

    Jørgensen, L N; Wille-Jørgensen, P; Hauch, O

    1993-01-01

    To evaluate the thromboprophylactic use of low molecular weight heparins (LMWHs), publications from 27 orthopaedic trials and 35 studies of patients undergoing general or gynaecological surgery were scrutinized and subjected to a partial meta-analysis. In orthopaedic surgery, LMWHs were superior...... to placebo or dextran and at least as efficient as unfractionated heparin in the prevention of deep vein thrombosis (DVT). Compared with unfractionated heparin, one of the LMWH preparations significantly reduced the total incidence of DVT. The rate of non-fatal pulmonary embolism was 0.49 per cent...

  7. Increased accuracy in heparin and protamine administration decreases bleeding

    DEFF Research Database (Denmark)

    Runge, Marx; Møller, Christian H; Steinbrüchel, Daniel A

    2009-01-01

    Three to 5 percent of the patients undergoing cardiac surgery are reoperated because of bleeding. When a surgical cause can be excluded, heparin/protamine mismatch may be considered. Insufficient reversal of heparin and overdosing of protamine may cause postoperative bleeding. The purpose......). A reduced number of patients needed blood transfusions in the RxDx group, although this was not statistically significant (19% vs. 38%, respectively; p = .13). Initial heparin dose was significantly reduced in the RxDx group (250 mg; range, 100-375 mg) compared with the control group (300 mg; range, 200...

  8. Results of the HepZero study comparing heparin-grafted membrane and standard care show that heparin-grafted dialyzer is safe and easy to use for heparin-free dialysis

    NARCIS (Netherlands)

    Laville, Maurice; Dorval, Marc; Ros, Joan Fort; Fay, Renaud; Cridlig, Joelle; Nortier, Joelle L.; Juillard, Laurent; Debska-Slizien, Alicja; Lorente, Loreto Fernandez; Thibaudin, Damien; Franssen, Casper; Schulz, Michael; Moureau, Frederique; Loughraieb, Nathalie; Rossignol, Patrick

    2014-01-01

    Heparin is used to prevent clotting during hemodialysis, but heparin-free hemodialysis is sometimes needed to decrease the risk of bleeding. The HepZero study is a randomized, multicenter international controlled open-label trial comparing no-heparin hemodialysis strategies designed to assess

  9. Clinical effects of low-molecular-weight heparin combined with ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research August 2016; 15 (8): 1787-1792 ... Keywords: Acute pancreatitis, Low-molecular-weight heparin, Multiple organ function syndrome,. APACHE II score ... mediators by lowering the expression of.

  10. Epidermal Overexpression of Xenobiotic Receptor PXR Impairs the Epidermal Barrier and Triggers Th2 Immune Response.

    Science.gov (United States)

    Elentner, Andreas; Schmuth, Matthias; Yannoutsos, Nikolaos; Eichmann, Thomas O; Gruber, Robert; Radner, Franz P W; Hermann, Martin; Del Frari, Barbara; Dubrac, Sandrine

    2018-01-01

    The skin is in daily contact with environmental pollutants, but the long-term effects of such exposure remain underinvestigated. Many of these toxins bind and activate the pregnane X receptor (PXR), a ligand-activated transcription factor that regulates genes central to xenobiotic metabolism. The objective of this work was to investigate the effect of constitutive activation of PXR in the basal layer of the skin to mimic repeated skin exposure to noxious molecules. We designed a transgenic mouse model that overexpresses the human PXR gene linked to the herpes simplex VP16 domain under the control of the keratin 14 promoter. We show that transgenic mice display increased transepidermal water loss and elevated skin pH, abnormal stratum corneum lipids, focal epidermal hyperplasia, activated keratinocytes expressing more thymic stromal lymphopoietin, a T helper type 2/T helper type 17 skin immune response, and increased serum IgE. Furthermore, the cutaneous barrier dysfunction precedes development of the T helper type 2/T helper type 17 inflammation in transgenic mice, thereby mirroring the time course of atopic dermatitis development in humans. Moreover, further experiments suggest increased PXR signaling in the skin of patients with atopic dermatitis when compared with healthy skin. Thus, PXR activation by environmental pollutants may compromise epidermal barrier function and favor an immune response resembling atopic dermatitis. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Multistep change in epidermal growth factor receptors during spontaneous neoplastic progression in Chinese hamster embryo fibroblasts

    International Nuclear Information System (INIS)

    Wakshull, E.; Kraemer, P.M.; Wharton, W.

    1985-01-01

    Whole Chinese hamster embryo lineages have been shown to undergo multistep spontaneous neoplastic progression during serial passage in culture. The authors have studied the binding, internalization, and degradation of 125 I-labeled epidermal growth factor at four different stages of transformation. The whole Chinese hamster embryo cells lost cell surface epidermal growth factor receptors gradually during the course of neoplastic progression until only 10% of the receptor number present in the early-passage cells (precrisis) were retained in the late-passage cells (tumorigenic). No differences in internalization rates, chloroquine sensitivity, or ability to degrade hormone between the various passage levels were seen. No evidence for the presence in conditioned medium of transforming growth factors which might mask or down-regulate epidermal growth factor receptor was obtained. These results suggest that a reduction in cell surface epidermal growth factor receptor might be an early event during spontaneous transformation in whole Chinese hamster embryo cells

  12. Steroid hormone and epidermal growth factor receptors in meningiomas.

    Science.gov (United States)

    Horsfall, D J; Goldsmith, K G; Ricciardelli, C; Skinner, J M; Tilley, W D; Marshall, V R

    1989-11-01

    A prospective study of steroid hormone and epidermal growth factor receptor expression in 57 meningiomas is presented. Scatchard analysis of radioligand binding identified 20% of meningiomas as expressing classical oestrogen receptors (ER) at levels below that normally accepted for positivity, the remainder being negative. ER could not be visualized in any meningioma using immunocytochemistry. Alternatively, 74% of meningiomas demonstrated the presence of progesterone receptors (PR) by Scatchard analysis, the specificity of which could not be attributed to glucocorticoid or androgen receptors. Confirmation of classical PR presence was determined by immunocytochemical staining. The presence of epidermal growth factor receptor (EGFR) was demonstrated in 100% of meningiomas using immunocytochemical staining. These data are reviewed in the context of previously reported results and are discussed in relation to the potential for medical therapy as an adjunct to surgery.

  13. Evolution of dinosaur epidermal structures.

    Science.gov (United States)

    Barrett, Paul M; Evans, David C; Campione, Nicolás E

    2015-06-01

    Spectacularly preserved non-avian dinosaurs with integumentary filaments/feathers have revolutionized dinosaur studies and fostered the suggestion that the dinosaur common ancestor possessed complex integumentary structures homologous to feathers. This hypothesis has major implications for interpreting dinosaur biology, but has not been tested rigorously. Using a comprehensive database of dinosaur skin traces, we apply maximum-likelihood methods to reconstruct the phylogenetic distribution of epidermal structures and interpret their evolutionary history. Most of these analyses find no compelling evidence for the appearance of protofeathers in the dinosaur common ancestor and scales are usually recovered as the plesiomorphic state, but results are sensitive to the outgroup condition in pterosaurs. Rare occurrences of ornithischian filamentous integument might represent independent acquisitions of novel epidermal structures that are not homologous with theropod feathers. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  14. Biochemistry of epidermal stem cells.

    Science.gov (United States)

    Eckert, Richard L; Adhikary, Gautam; Balasubramanian, Sivaprakasam; Rorke, Ellen A; Vemuri, Mohan C; Boucher, Shayne E; Bickenbach, Jackie R; Kerr, Candace

    2013-02-01

    The epidermis is an important protective barrier that is essential for maintenance of life. Maintaining this barrier requires continuous cell proliferation and differentiation. Moreover, these processes must be balanced to produce a normal epidermis. The stem cells of the epidermis reside in specific locations in the basal epidermis, hair follicle and sebaceous glands and these cells are responsible for replenishment of this tissue. A great deal of effort has gone into identifying protein epitopes that mark stem cells, in identifying stem cell niche locations, and in understanding how stem cell populations are related. We discuss these studies as they apply to understanding normal epidermal homeostasis and skin cancer. An assortment of stem cell markers have been identified that permit assignment of stem cells to specific regions of the epidermis, and progress has been made in understanding the role of these cells in normal epidermal homeostasis and in conditions of tissue stress. A key finding is the multiple stem cell populations exist in epidermis that give rise to different structures, and that multiple stem cell types may contribute to repair in damaged epidermis. Understanding epidermal stem cell biology is likely to lead to important therapies for treating skin diseases and cancer, and will also contribute to our understanding of stem cells in other systems. This article is part of a Special Issue entitled Biochemistry of Stem Cells. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Biochemistry of epidermal stem cells☆

    Science.gov (United States)

    Eckert, Richard L.; Adhikary, Gautam; Balasubramanian, Sivaprakasam; Rorke, Ellen A.; Vemuri, Mohan C.; Boucher, Shayne E.; Bickenbach, Jackie R.; Kerr, Candace

    2014-01-01

    Background The epidermis is an important protective barrier that is essential for maintenance of life. Maintaining this barrier requires continuous cell proliferation and differentiation. Moreover, these processes must be balanced to produce a normal epidermis. The stem cells of the epidermis reside in specific locations in the basal epidermis, hair follicle and sebaceous glands and these cells are responsible for replenishment of this tissue. Scope of review A great deal of effort has gone into identifying protein epitopes that mark stem cells, in identifying stem cell niche locations, and in understanding how stem cell populations are related. We discuss these studies as they apply to understanding normal epidermal homeostasis and skin cancer. Major conclusions An assortment of stem cell markers have been identified that permit assignment of stem cells to specific regions of the epidermis, and progress has been made in understanding the role of these cells in normal epidermal homeostasis and in conditions of tissue stress. A key finding is the multiple stem cell populations exist in epidermis that give rise to different structures, and that multiple stem cell types may contribute to repair in damaged epidermis. General significance Understanding epidermal stem cell biology is likely to lead to important therapies for treating skin diseases and cancer, and will also contribute to our understanding of stem cells in other systems. This article is part of a Special Issue entitled Biochemistry of Stem Cells. PMID:22820019

  16. Advanced nanocarriers based on heparin and its derivatives for cancer management.

    Science.gov (United States)

    Yang, Xiaoye; Du, Hongliang; Liu, Jiyong; Zhai, Guangxi

    2015-02-09

    To obtain a satisfying anticancer effect, rationally designed nanocarriers are intensively studied. In this field, heparin and its derivatives have been widely attempted recently as potential component of nanocarriers due to their unique biological and physiochemical features, especially the anticancer activity. This review focuses on state-of-the-art nanocarriers with heparin/heparin derivatives as backbone or coating material. At the beginning, the unique advantages of heparin used in cancer nanotechnology are discussed. After that, different strategies of heparin chemical modification are reviewed, laying the foundation of developing various nanocarriers. Then a systematic summary of diverse nanoparticles with heparin as component is exhibited, involving heparin-drug conjugate, polymeric nanoparticles, nanogels, polyelectrolyte complex nanoparticles, and heparin-coated organic and inorganic nanoparticles. The application of these nanoparticles in various novel cancer therapy (containing targeted therapy, magnetic therapy, photodynamic therapy, and gene therapy) will be highlighted. Finally, future challenges and opportunities of heparin-based biomaterials in cancer nanotechnology are discussed.

  17. In vitro anticoagulation monitoring of low-molecular-weight heparin

    Institute of Scientific and Technical Information of China (English)

    WANG Jian-qi; SHI Xu-bo; YANG Jin-gang; HU Da-yi

    2009-01-01

    Background Although low-molecular-weight heparin has replaced unfractionated heparin to become the primary anticoagulation drug for treatment of acute coronary syndrome, there is no convenient bedside monitoring method. We explored the best laboratory monitoring method of low-molecular-weight heparins (enoxapadn, dalteparin, and nadroparin) by use of the Sonoclot coagulation analyzer to monitor the activated clotting time.Methods Atotal of 20 healthy volunteers were selected and 15 ml of fasting venous blood samples were collected and incubated. Four coagulants, kaolin, diatomite, glass bead, and magnetic stick, were used to determine the activated clotting time of the low-molecular-weight heparins at different in vitro anti-Xa factor concentrations. A correlation analysis was made to obtain the regression equation. The activated clotting time of the different low-molecular-weight heparins with the same anti-Xa factor concentration was monitored when the coagulant glass beads were applied. Results The activated clotting time measured using the glass beads, diatomite, kaolin, and magnetic stick showed a linear correlation with the concentration of nadroparin (r= 0.964, 0.966, 0.970, and 0.947, respectively). The regression equation showed that the linear slopes of different coagulants were significantly different (glass beads 230.03 s/IU,diatomite 89.91 s/IU, kaolin 50.87 s/IU, magnetic stick could not be calculated). When the concentration of the anti-Xa factor was the same for different low-molecular-weight heparins, the measured activated clotting time was different after the application of the glass bead coagulant.Conclusions The glass bead coagulant is most feasible for monitoring the in vitro anticoagulation activity of nadroparin.The different effects of different low-molecular-weight heparins on the activated clotting time may be related to the different anti-Ila activities.

  18. Disappearance of a low molecular weight heparin fraction (CY 216) differs from standard heparin in rabbits

    International Nuclear Information System (INIS)

    Boneu, B.; Buchanan, M.R.; Caranobe, C.; Gabaig, A.M.; Dupouy, D.; Sie, P.; Hirsh, J.

    1987-01-01

    In previous studies, we have reported that standard heparin (SH) was cleared by two mechanisms, a saturable mechanism which predominated at low doses (less than 100 anti-factor Xa U/kg) and a non-saturable mechanism which predominated at higher doses, when the first mechanism became saturated. In this study, we examined the importance of these two mechanisms in the disappearance of a low molecular weight heparin fraction (LMWH) (CY 216), by comparing the pharmacokinetics and the pharmacodynamics of a wide range of doses of SH and CY 216 (1.5 to 500 anti-factor Xa U/kg). Pharmacokinetics was measured as the disappearance of 125 I-radiolabelled SH or CY 216. Pharmacodynamics was measured as the disappearance of the anti-factor Xa activity of SH and CY 216. We found that the saturable mechanism contributed little to the disappearance of CY 216 and that it was cleared predominantly by the non-saturable mechanism at all doses tested. Thus, at low doses (less than 100 anti-factor Xa U/kg), SH was cleared more rapidly than CY 216, whereas at higher doses, CY 216 was cleared more rapidly than SH. We conclude that the mechanism of disappearance of LMWH's differ significantly from those of SH, and that this difference may explain the apparent prolonged anticoagulant activity of LMWH's within the therapeutic range doses

  19. Veno-venous bypass without systemic heparinization using a centrifugal pump: a blind comparison of a heparin bonded circuit versus a non heparin bonded circuit

    NARCIS (Netherlands)

    van der Hulst, V. P.; Henny, C. P.; Moulijn, A. C.; Engbers, G.; ten Cate, H.; Gründeman, P. F.; Klopper, P. J.

    1989-01-01

    Veno-venous bypass without the use of systemic heparinization has recently become of increasing interest for application during liver transplantation and surgery on the large abdominal veins. However, possible adverse effects on blood components as demonstrated by means of hematologic and hemostatic

  20. Pharmacokinetics of heparin and related polysaccharides

    International Nuclear Information System (INIS)

    Boneu, B.; Dol, F.; Caranobe, C.; Sie, P.; Houin, G.

    1989-01-01

    The pharmacodynamic profile of standard heparin (SH), a low molecular weight derivative (CY 216) and of dermatan sulfate (DS), a new potential antithrombotic drug, was investigated in the rabbit over a large range of doses. After bolus i.v. injection of low doses, the biological activity of SH disappeared exponentially; however, its half-life was prolonged when the dose injected increased, and over 158 micrograms/kg (100 anti-factor Xa U/kg) the biological activity disappeared as a concave-convex curve. CY 216 disappeared more slowly than SH at low doses but faster than SH at higher doses. More than 90% of the DS biological activity present 1 minute after the i.v. injection disappeared exponentially without dose-dependent effects. Increasing doses of the three drugs were then delivered for 5 h under continuous infusions. Below 500 micrograms/kg/h the DS and CY 216 plateau concentrations were higher than that of SH while above this dose the SH concentration was higher than that of DS and CY 216. These observations may be explained by the results of pharmacokinetics experiments where 125 I-labeled compounds were delivered by bolus i.v. injection in association with increasing doses of their unlabeled counterparts. For SH there was a 10-fold difference between the half-life of the lower dose (32 micrograms/kg or 5 anti-factor Xa U/kg) and that of the higher dose (3200 micrograms/kg); it was demonstrated that the half-life of SH continuously shortened as its plasma concentration decreased. In contrast the CY 216 and DS half-lives were very close, independent of the dose delivered, and therefore longer than that of SH at low doses and shorter than that of SH at higher doses

  1. Potentiation of C1-esterase inhibitor by heparin and interactions with C1s protease as assessed by surface plasmon resonance.

    Science.gov (United States)

    Rajabi, Mohsen; Struble, Evi; Zhou, Zhaohua; Karnaukhova, Elena

    2012-01-01

    Human C1-esterase inhibitor (C1-INH) is a multifunctional plasma protein with a wide range of inhibitory and non-inhibitory properties, mainly recognized as a key down-regulator of the complement and contact cascades. The potentiation of C1-INH by heparin and other glycosaminoglycans (GAGs) regulates a broad spectrum of C1-INH activities in vivo both in normal and disease states. SCOPE OF RESEARCH: We have studied the potentiation of human C1-INH by heparin using Surface Plasmon Resonance (SPR), circular dichroism (CD) and a functional assay. To advance a SPR for multiple-unit interaction studies of C1-INH we have developed a novel (consecutive double capture) approach exploring different immobilization and layout. Our SPR experiments conducted in three different design versions showed marked acceleration in C1-INH interactions with complement protease C1s as a result of potentiation of C1-INH by heparin (from 5- to 11-fold increase of the association rate). Far-UV CD studies suggested that heparin binding did not alter C1-INH secondary structure. Functional assay using chromogenic substrate confirmed that heparin does not affect the amidolytic activity of C1s, but does accelerate its consumption due to C1-INH potentiation. This is the first report that directly demonstrates a significant acceleration of the C1-INH interactions with C1s due to heparin by using a consecutive double capture SPR approach. The results of this study may be useful for further C-INH therapeutic development, ultimately for the enhancement of current C1-INH replacement therapies. Published by Elsevier B.V.

  2. Degranulating mast cells in fibrotic regions of human tumors and evidence that mast cell heparin interferes with the growth of tumor cells through a mechanism involving fibroblasts

    International Nuclear Information System (INIS)

    Samoszuk, Michael; Kanakubo, Emi; Chan, John K

    2005-01-01

    The purpose of this study was to test the hypothesis that mast cells that are present in fibrotic regions of cancer can suppress the growth of tumor cells through an indirect mechanism involving peri-tumoral fibroblasts. We first immunostained a wide variety of human cancers for the presence of degranulated mast cells. In a subsequent series of controlled in vitro experiments, we then co-cultured UACC-812 human breast cancer cells with normal fibroblasts in the presence or absence of different combinations and doses of mast cell tryptase, mast cell heparin, a lysate of the human mast cell line HMC-1, and fibroblast growth factor-7 (FGF-7), a powerful, heparin-binding growth factor for breast epithelial cells. Degranulating mast cells were localized predominantly in the fibrous tissue of every case of breast cancer, head and neck cancer, lung cancer, ovarian cancer, non-Hodgkin's lymphoma, and Hodgkin's disease that we examined. Mast cell tryptase and HMC-1 lysate had no significant effect on the clonogenic growth of cancer cells co-cultured with fibroblasts. By contrast, mast cell heparin at multiple doses significantly reduced the size and number of colonies of tumor cells co-cultured with fibroblasts, especially in the presence of FGF-7. Neither heparin nor FGF-7, individually or in combination, produced any significant effect on the clonogenic growth of breast cancer cells cultured without fibroblasts. Degranulating mast cells are restricted to peri-tumoral fibrous tissue, and mast cell heparin is a powerful inhibitor of clonogenic growth of tumor cells co-cultured with fibroblasts. These results may help to explain the well-known ability of heparin to inhibit the growth of primary and metastatic tumors

  3. Degranulating mast cells in fibrotic regions of human tumors and evidence that mast cell heparin interferes with the growth of tumor cells through a mechanism involving fibroblasts

    Directory of Open Access Journals (Sweden)

    Kanakubo Emi

    2005-09-01

    Full Text Available Abstract Background The purpose of this study was to test the hypothesis that mast cells that are present in fibrotic regions of cancer can suppress the growth of tumor cells through an indirect mechanism involving peri-tumoral fibroblasts. Methods We first immunostained a wide variety of human cancers for the presence of degranulated mast cells. In a subsequent series of controlled in vitro experiments, we then co-cultured UACC-812 human breast cancer cells with normal fibroblasts in the presence or absence of different combinations and doses of mast cell tryptase, mast cell heparin, a lysate of the human mast cell line HMC-1, and fibroblast growth factor-7 (FGF-7, a powerful, heparin-binding growth factor for breast epithelial cells. Results Degranulating mast cells were localized predominantly in the fibrous tissue of every case of breast cancer, head and neck cancer, lung cancer, ovarian cancer, non-Hodgkin's lymphoma, and Hodgkin's disease that we examined. Mast cell tryptase and HMC-1 lysate had no significant effect on the clonogenic growth of cancer cells co-cultured with fibroblasts. By contrast, mast cell heparin at multiple doses significantly reduced the size and number of colonies of tumor cells co-cultured with fibroblasts, especially in the presence of FGF-7. Neither heparin nor FGF-7, individually or in combination, produced any significant effect on the clonogenic growth of breast cancer cells cultured without fibroblasts. Conclusion Degranulating mast cells are restricted to peri-tumoral fibrous tissue, and mast cell heparin is a powerful inhibitor of clonogenic growth of tumor cells co-cultured with fibroblasts. These results may help to explain the well-known ability of heparin to inhibit the growth of primary and metastatic tumors.

  4. The intracellular uptake and protracted release of exogenous heparins by cultured endothelial cells

    International Nuclear Information System (INIS)

    Hiebert, L.M.; McDuffie, N.M.

    1989-01-01

    Heparins from bovine or porcine sources were fed in media for 48 hrs to cultured porcine aortic and human umbilical vein endothelial cells. Heparin was found in pericellular and cellular fractions after extraction by chemical methods and 125 I radiolabelled heparins were recovered when radiolabelled heparin was included in the feed. Even after washing and media changes heparin was detected in media and cell fractions up to 6 days post feeding. Metachromatic vacuoles within cells were demonstrated histologically up to 7 days post feeding after staining with toluidine blue. This is the first report of protracted internalization of exogenous heparin by cultured endothelial cells with concurrent prolonged release of the heparin to the media. This clearly demonstrates that the endothelium plays an important role in the distribution and metabolism of heparin

  5. Quantitation of heparosan with heparin lyase III and spectrophotometry.

    Science.gov (United States)

    Huang, Haichan; Zhao, Yingying; Lv, Shencong; Zhong, Weihong; Zhang, Fuming; Linhardt, Robert J

    2014-02-15

    Heparosan is Escherichia coli K5 capsule polysaccharide, which is the key precursor for preparing bioengineered heparin. A rapid and effective quantitative method for detecting heparosan is important in the large-scale production of heparosan. Heparin lyase III (Hep III) effectively catalyzes the heparosan depolymerization, forming unsaturated disaccharides that are measurable using a spectrophotometer at 232 nm. We report a new method for the quantitative detection of heparosan with heparin lyase III and spectrophotometry that is safer and more specific than the traditional carbazole assay. In an optimized detection system, heparosan at a minimum concentration of 0.60 g/L in fermentation broth can be detected. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Heparin-Based Nanoparticles: An Overview of Their Applications

    Directory of Open Access Journals (Sweden)

    Maria del Pilar Rodriguez-Torres

    2018-01-01

    Full Text Available This review deals with nanoparticles synthesized using heparin. Such nanoparticles have been widely studied since a long time ago, obtaining satisfactory outcomes. An outstanding aspect of these nanoparticles is that they possess good biocompatible characteristics, and since heparin is produced in the human body within the mast cells, this makes these nanoparticles useful for future applications like imaging, disease and cancer treatment, and antibacterial activity. They can also be used for applications that are not oriented directly to the medical and biological areas such as in the case of analyte detection in aqueous solution, although such studies are very few. These nanoparticles synthesis is mainly through wet chemistry methods, using heparin that could have been modified or not.

  7. Sequence similarity between the erythrocyte binding domain 1 of the Plasmodium vivax Duffy binding protein and the V3 loop of HIV-1 strain MN reveals binding residues for the Duffy Antigen Receptor for Chemokines

    Directory of Open Access Journals (Sweden)

    Garry Robert F

    2011-01-01

    Full Text Available Abstract Background The surface glycoprotein (SU, gp120 of the human immunodeficiency virus (HIV must bind to a chemokine receptor, CCR5 or CXCR4, to invade CD4+ cells. Plasmodium vivax uses the Duffy Binding Protein (DBP to bind the Duffy Antigen Receptor for Chemokines (DARC and invade reticulocytes. Results Variable loop 3 (V3 of HIV-1 SU and domain 1 of the Plasmodium vivax DBP share a sequence similarity. The site of amino acid sequence similarity was necessary, but not sufficient, for DARC binding and contained a consensus heparin binding site essential for DARC binding. Both HIV-1 and P. vivax can be blocked from binding to their chemokine receptors by the chemokine, RANTES and its analog AOP-RANTES. Site directed mutagenesis of the heparin binding motif in members of the DBP family, the P. knowlesi alpha, beta and gamma proteins abrogated their binding to erythrocytes. Positively charged residues within domain 1 are required for binding of P. vivax and P. knowlesi erythrocyte binding proteins. Conclusion A heparin binding site motif in members of the DBP family may form part of a conserved erythrocyte receptor binding pocket.

  8. Changes in heparin dose response slope during cardiac surgery: possible result in inaccuracy in predicting heparin bolus dose requirement to achieve target ACT.

    Science.gov (United States)

    Ichikawa, Junko; Mori, Tetsu; Kodaka, Mitsuharu; Nishiyama, Keiko; Ozaki, Makoto; Komori, Makiko

    2017-09-01

    The substantial interpatient variability in heparin requirement has led to the use of a heparin dose response (HDR) technique. The accuracy of Hepcon-based heparin administration in achieving a target activated clotting time (ACT) using an HDR slope remains controversial. We prospectively studied 86 adult patients scheduled for cardiac surgery requiring cardiopulmonary bypass. The total dose of calculated heparin required for patient and pump priming was administered simultaneously to achieve a target ACT of 450 s for HDR on the Hepcon HMS system. Blood samples were obtained after the induction of anesthesia, at 3 min after heparin administration and after the initiation of CPB to measure kaolin ACT, HDR slope, whole-blood heparin concentration based on the HDR slope and anti-Xa heparin concentration, antithrombin and complete blood count. The target ACT of 450 s was not achieved in 68.6% of patients. Compared with patients who achieved the target ACT, those who failed to achieve their target ACT had a significantly higher platelet count at baseline. Correlation between the HDR slope and heparin sensitivity was poor. Projected heparin concentration and anti-Xa heparin concentration are not interchangeable based on the Bland-Altman analysis. It can be hypothesized that the wide discrepancy in HDR slope versus heparin sensitivity may be explained by an inaccurate prediction of the plasma heparin level and/or the change in HDR of individual patients, depending on in vivo factors such as extravascular sequestration of heparin, decreased intrinsic antithrombin activity level and platelet count and/or activity.

  9. Histones Differentially Modulate the Anticoagulant and Profibrinolytic Activities of Heparin, Heparin Derivatives, and Dabigatran.

    Science.gov (United States)

    Ammollo, Concetta Tiziana; Semeraro, Nicola; Carratù, Maria Rosaria; Colucci, Mario; Semeraro, Fabrizio

    2016-02-01

    The antithrombin activity of unfractionated heparin (UFH) is offset by extracellular histones, which, along with DNA, represent a novel mediator of thrombosis and a structural component of thrombi. Here, we systematically evaluated the effect of histones, DNA, and histone-DNA complexes on the anticoagulant and profibrinolytic activities of UFH, its derivatives enoxaparin and fondaparinux, and the direct thrombin inhibitor dabigatran. Thrombin generation was assessed by calibrated automated thrombinography, inhibition of factor Xa and thrombin by synthetic substrates, tissue plasminogen activator-mediated clot lysis by turbidimetry, and thrombin-activatable fibrinolysis inhibitor (TAFI) activation by a functional assay. Histones alone delayed coagulation and slightly stimulated fibrinolysis. The anticoagulant activity of UFH and enoxaparin was markedly inhibited by histones, whereas that of fondaparinux was enhanced. Histones neutralized both the anti-Xa and anti-IIa activities of UFH and preferentially blocked the anti-IIa activity of enoxaparin. The anti-Xa activity of fondaparinux was not influenced by histones when analyzed by chromogenic substrates, but was potentiated in a plasma prothrombinase assay. Histones inhibited the profibrinolytic activity of UFH and enoxaparin and enhanced that of fondaparinux by acting on the modulation of TAFI activation by anticoagulants. Histone H1 was mainly responsible for these effects. Histone-DNA complexes, as well as intact neutrophil extracellular traps, impaired the activities of UFH, enoxaparin, and fondaparinux. Dabigatran was not noticeably affected by histones and/or DNA, whatever the assay performed. In conclusion, histones and DNA present in the forming clot may variably influence the antithrombotic activities of anticoagulants, suggesting a potential therapeutic advantage of dabigatran and fondaparinux over heparins. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  10. The effect of different forms of heparin on point-of-care blood gas ...

    African Journals Online (AJOL)

    and heparin vacutainers on blood gas and electrolyte analysis and ... This prospective, cross-sectional study took place in the ED of a ... the effect of two concentrations of liquid heparin and the use of heparin vacutainers on the reliability of blood gas ... Germany) and (iv) a 2 mL plastic syringe (BD) washed with 5 000 IU/.

  11. Coexistence of Antiphospholipid Syndrome and Heparin-Induced Thrombocytopenia in a Patient with Recurrent Venous Thromboembolism

    Directory of Open Access Journals (Sweden)

    Samuel Adediran

    2017-01-01

    Full Text Available Heparin-induced thrombocytopenia (HIT is a prothrombotic adverse drug reaction in which heparin forms complexes with platelet factor 4 forming neoantigens that are recognized by autoantibodies. Antiphospholipid syndrome (APS is similar to HIT in that it is mediated by autoantibodies that are also prothrombotic. We present a case of rare coexistence of antiphospholipid antibody syndrome and heparin-induced thrombocytopenia.

  12. A genome-wide association study of heparin-induced thrombocytopenia using an electronic medical record

    DEFF Research Database (Denmark)

    Karnes, Jason H; Cronin, Robert M; Rollin, Jerome

    2015-01-01

    Heparin-induced thrombocytopenia (HIT) is an unpredictable, potentially catastrophic adverse effect of heparin treatment resulting from an immune response to platelet factor 4 (PF4)/heparin complexes. No genome-wide evaluations have been performed to identify potential genetic influences on HIT. ...

  13. 12500 E heparin and 12500 E of a semisynthetic heparin analogue (SSHA) in preventing thrombosis during radiotherapy of gynaecological carcinomas

    International Nuclear Information System (INIS)

    Hilscher, T.M.

    1983-01-01

    The effects of 12500 E calcium heparin given once daily were contrasted with those seen under daily treatment with 12500 E of a semisynthetic heparin analogue (SSHA) and evaluated using iodine-125-labelled fibrinogen. The study included 80 patients, who were randomly assigned to the two treatment groups on a 1:1 basis. The findings revealed here led to the conclusion that both drugs, administered once daily by the subcutaneous route, were effective in preventing the occurrence of thrombosis during radiation treatment of gynaecological tumours. (orig./MG) [de

  14. Proteolytic activation transforms heparin cofactor II into a host defense molecule.

    Science.gov (United States)

    Kalle, Martina; Papareddy, Praveen; Kasetty, Gopinath; Tollefsen, Douglas M; Malmsten, Martin; Mörgelin, Matthias; Schmidtchen, Artur

    2013-06-15

    The abundant serine proteinase inhibitor heparin cofactor II (HCII) has been proposed to inhibit extravascular thrombin. However, the exact physiological role of this plasma protein remains enigmatic. In this study, we demonstrate a previously unknown role for HCII in host defense. Proteolytic cleavage of the molecule induced a conformational change, thereby inducing endotoxin-binding and antimicrobial properties. Analyses employing representative peptide epitopes mapped these effects to helices A and D. Mice deficient in HCII showed increased susceptibility to invasive infection by Pseudomonas aeruginosa, along with a significantly increased cytokine response. Correspondingly, decreased levels of HCII were observed in wild-type animals challenged with bacteria or endotoxin. In humans, proteolytically cleaved HCII forms were detected during wounding and in association with bacteria. Thus, the protease-induced uncovering of cryptic epitopes in HCII, which transforms the molecule into a host defense factor, represents a previously unknown regulatory mechanism in HCII biology and innate immunity.

  15. Acid-citrate-dextrose compared with heparin in the preparation of in vivo/in vitro technetium-99m red blood cells

    International Nuclear Information System (INIS)

    Porter, W.C.; Dees, S.M.; Freitas, J.E.; Dworkin, H.J.

    1983-01-01

    Red blood cells labeled in vivo/in vitro with Tc-99m (Tc-99m RBC) were prepared in a series of 21 patients and two normal volunteers. In each subject both heparin and acid-citrate-dextrose (ACD) solutions were used to label tandem blood samples. The immediate preinjection binding efficiency (BE) was then determined. In each of the 23 studies, the ACD preparation yielded superior BE. The average BE was 93.47% (+/- 3.78) with ACD and 87.23% (+/- 4.29) with heparin. With the ACD method the effect of carrier Tc-99 may be as great as a 24% reduction in BE observed when initial eluates from long-ingrowth-time generators were used. Improved image quality with minimal renal and urinary-bladder activity results with ACD labeling. It is concluded that the use of ACD results in superior RBC labeling with less nontarget activity relative to heparin and is preferred over heparin for preparing in vivo/in vitro Tc-99m RBC

  16. Cellular Responses Modulated by FGF-2 Adsorbed on Albumin/Heparin Layer-by-Layer Assemblies.

    Science.gov (United States)

    Kumorek, Marta; Kubies, Dana; Filová, Elena; Houska, Milan; Kasoju, Naresh; Mázl Chánová, Eliška; Matějka, Roman; Krýslová, Markéta; Bačáková, Lucie; Rypáček, František

    2015-01-01

    In a typical cell culture system, growth factors immobilized on the cell culture surfaces can serve as a reservoir of bio-signaling molecules, without the need to supplement them additionally into the culture medium. In this paper, we report on the fabrication of albumin/heparin (Alb/Hep) assemblies for controlled binding of basic fibroblast growth factor (FGF-2). The surfaces were constructed by layer-by-layer adsorption of polyelectrolytes albumin and heparin and were subsequently stabilized by covalent crosslinking with glutaraldehyde. An analysis of the surface morphology by atomic force microscopy showed that two Alb/Hep bilayers are required to cover the surface of substrate. The formation of the Alb/Hep assemblies was monitored by the surface plasmon resonance (SPR), the infrared multiinternal reflection spectroscopy (FTIR MIRS) and UV/VIS spectroscopy. The adsorption of FGF-2 on the cross-linked Alb/Hep was followed by SPR. The results revealed that FGF-2 binds to the Alb/Hep assembly in a dose and time-dependent manner up to the surface concentration of 120 ng/cm(2). The bioactivity of the adsorbed FGF-2 was assessed in experiments in vitro, using calf pulmonary arterial endothelial cells (CPAE). CPAE cells could attach and proliferate on Alb/Hep surfaces. The adsorbed FGF-2 was bioactive and stimulated both the proliferation and the differentiation of CPAE cells. The improvement was more pronounced at a lower FGF-2 surface concentration (30 ng/cm(2)) than on surfaces with a higher concentration of FGF-2 (120 ng/cm(2)).

  17. Cyclic Voltammetry of Biopolymer Heparin at PVC Plasticized Liquid Membrane

    Czech Academy of Sciences Publication Activity Database

    Samec, Zdeněk; Trojánek, Antonín; Langmaier, Jan; Samcová, E.

    2003-01-01

    Roč. 5, - (2003), s. 867-870 ISSN 1388-2481 R&D Projects: GA ČR GA203/04/0424 Institutional research plan: CEZ:AV0Z4040901 Keywords : cyclic voltammetry * PVC plasticized liquit membrane * heparin Subject RIV: CG - Electrochemistry Impact factor: 2.300, year: 2003

  18. The Effect of Low Molecular Weight Heparins on Fracture Healing.

    Science.gov (United States)

    Kapetanakis, Stylianos; Nastoulis, Evangelos; Demesticha, Theano; Demetriou, Thespis

    2015-01-01

    Venous Thromboembolism is a serious complication in the trauma patient. The most commonly studied and used anticoagulant treatment in prophylaxis of thrombosis is heparin. The prolonged use of unfractionated heparin has been connected with increased incidence of osteoporotic fractures. Low molecular-weight-heparins (LMWHs) have been the golden rule in antithrombotic therapy during the previous two decades as a way to overcome the major drawbacks of unfractioned heparin. However there are few studies reporting the effects of LMWHs on bone repair after fractures. This review presents the studies about the effects of LMWHs on bone biology (bone cells and bone metabolism) and underlying the mechanisms by which LMWHs may impair fracture healing process. The authors' research based on literature concluded that there are no facts and statistics for the role of LMWHs on fracture healing process in humans and the main body of evidence of their role comes from in vitro and animal studies. Further large clinical studies designed to compare different types of LMWHs, in different dosages and in different patient or animal models are needed for exploring the effects of LMWHs on fracture healing process.

  19. 21 CFR 864.5680 - Automated heparin analyzer.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated heparin analyzer. 864.5680 Section 864.5680 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices § 864...

  20. Clinical effects of low-molecular-weight heparin combined with ...

    African Journals Online (AJOL)

    Purpose: To explore the clinical effects of low-molecular-weight heparin (LMWH) combined with ulinastatin (UTI) in children with acute pancreatitis. Methods: In total, 560 patients with severe acute pancreatitis treated at Binzhou People's Hospital, Shandong, China, from April 2012 to June 2014 were enrolled in this study.

  1. Alternative method for determination of contaminated heparin using chiral recognition.

    Science.gov (United States)

    Szekely, J; Collins, M; Currie, C A

    2014-05-15

    Since 2008 a significant amount of work has focused on the development of methods to analyze contaminated heparin. This work focuses on utilizing heparin's ability to serve as a chiral selector as a means for determining contamination. Specifically, the effect of contamination on the separation of pheniramine and chloroquine enantiomers was explored. Separations were conducted using heparin contaminated with chondroitin sulfate at varying levels. For each pair of enantiomers, electrophoretic mobility and resolution were calculated. For pheniramine enantiomers, an increase in contamination leads to a decrease in the electrophoretic mobility and resolution. A linear relationship between contamination level and electrophoretic mobility of the pheniramine enantiomers was observed for the entire contamination range. A linear relationship was also found between contamination level and resolution of the enantiomers between 0 and 70 percent contamination. For the separation of chloroquine enantiomers, it was found that at low levels of contamination, the resolution of enantiomers was increased due to the secondary interaction between the chloroquine enantiomers and the chondroitin sulfate. Results of this study illustrate the potential of using chiral recognition as a means to determine heparin contamination as well as the improvement of the chiral resolution of chloroquine with the additional of low levels of chondroitin sulfate A. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Highly sensitive ratiometric detection of heparin and its oversulfated chondroitin sulfate contaminant by fluorescent peptidyl probe.

    Science.gov (United States)

    Mehta, Pramod Kumar; Lee, Hyeri; Lee, Keun-Hyeung

    2017-05-15

    The selective and sensitive detection of heparin, an anticoagulant in clinics as well as its contaminant oversulfated chondroitin sulfate (OSCS) is of great importance. We first reported a ratiometric sensing method for heparin as well as OSCS contaminants in heparin using a fluorescent peptidyl probe (Pep1, pyrene-GSRKR) and heparin-digestive enzyme. Pep1 exhibited a highly sensitive ratiometric response to nanomolar concentration of heparin in aqueous solution over a wide pH range (2~11) and showed highly selective ratiometric response to heparin among biological competitors such as hyaluronic acid and chondroitin sulfate. Pep1 showed a linear ratiometric response to nanomolar concentrations of heparin in aqueous solutions and in human serum samples. The detection limit for heparin was calculated to be 2.46nM (R 2 =0.99) in aqueous solutions, 2.98nM (R 2 =0.98) in 1% serum samples, and 3.43nM (R 2 =0.99) in 5% serum samples. Pep1 was applied to detect the contaminated OSCS in heparin with heparinase I, II, and III, respectively. The ratiometric sensing method using Pep1 and heparinase II was highly sensitive, fast, and efficient for the detection of OSCS contaminant in heparin. Pep1 with heparinase II could detect as low as 0.0001% (w/w) of OSCS in heparin by a ratiometric response. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Toxic epidermal necrolysis successfully treated with etanercept.

    Science.gov (United States)

    Gubinelli, Emanuela; Canzona, Flora; Tonanzi, Tiziano; Raskovic, Desanka; Didona, Biagio

    2009-03-01

    Toxic epidermal necrolysis (TEN) is a rare and acute severe adverse reaction to drugs, characterised by massive apoptosis and widespread epidermal and mucosal detachment. Although no gold standard therapy exists, human i.v. immunoglobulins have recently been described as an effective treatment for this disease. We report a case of phenobarbital-induced TEN in a 59-year-old white woman where the epidermal detachment stopped 48 h after beginning the etanercept treatment with complete healing after 20 days. To the best of our knowledge, this is only the second reported case of TEN successfully treated with etanercept.

  4. A role for the epidermal growth factor receptor signaling in development of intestinal serrated polyps in mice and humans.

    Science.gov (United States)

    Bongers, Gerold; Muniz, Luciana R; Pacer, Michelle E; Iuga, Alina C; Thirunarayanan, Nanthakumar; Slinger, Erik; Smit, Martine J; Reddy, E Premkumar; Mayer, Lloyd; Furtado, Glaucia C; Harpaz, Noam; Lira, Sergio A

    2012-09-01

    Epithelial cancers can be initiated by activating mutations in components of the mitogen-activated protein kinase signaling pathway such as v-raf murine sarcoma viral oncogene homolog B1 (BRAF), v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS), or epidermal growth factor receptor (EGFR). Human intestinal serrated polyps are a heterogeneous group of benign lesions, but some progress to colorectal cancer. Tumors that arise from these polyps frequently contain activating mutations in BRAF or KRAS, but little is known about the role of EGFR activation in their development. Polyp samples were obtained from adults during screening colonoscopies at Mount Sinai Hospital in New York. We measured levels of EGFR protein and phosphorylation in human serrated polyps by immunohistochemical and immunoblot analyses. We generated transgenic mice that express the ligand for EGFR, Heparin-binding EGF-like growth factor (HB-EGF), in the intestine. EGFR and the extracellular-regulated kinases (ERK)1/2 were phosphorylated in serrated areas of human hyperplastic polyps (HPPs), sessile serrated adenomas, and traditional serrated adenomas. EGFR and ERK1/2 were phosphorylated in the absence of KRAS or BRAF activating mutations in a subset of HPP. Transgenic expression of the EGFR ligand HB-EGF in the intestines of mice promoted development of small cecal serrated polyps. Mice that expressed a combination of HB-EGF and US28 (a constitutively active, G-protein-coupled receptor that increases processing of HB-EGF from the membrane) rapidly developed large cecal serrated polyps. These polyps were similar to HPPs and had increased phosphorylation of EGFR and ERK1/2 within the serrated epithelium. Administration of pharmacologic inhibitors of EGFR or MAPK to these transgenic mice significantly reduced polyp development. Activation of EGFR signaling in the intestine of mice promotes development of serrated polyps. EGFR signaling also is activated in human HPPs, sessile serrated adenomas

  5. Heparin and Heparin-Derivatives in Post-Subarachnoid Hemorrhage Brain Injury: A Multimodal Therapy for a Multimodal Disease

    Directory of Open Access Journals (Sweden)

    Erik G. Hayman

    2017-05-01

    Full Text Available Pharmacologic efforts to improve outcomes following aneurysmal subarachnoid hemorrhage (aSAH remain disappointing, likely owing to the complex nature of post-hemorrhage brain injury. Previous work suggests that heparin, due to the multimodal nature of its actions, reduces the incidence of clinical vasospasm and delayed cerebral ischemia that accompany the disease. This narrative review examines how heparin may mitigate the non-vasospastic pathological aspects of aSAH, particularly those related to neuroinflammation. Following a brief review of early brain injury in aSAH and heparin’s general pharmacology, we discuss potential mechanistic roles of heparin therapy in treating post-aSAH inflammatory injury. These roles include reducing ischemia-reperfusion injury, preventing leukocyte extravasation, modulating phagocyte activation, countering oxidative stress, and correcting blood-brain barrier dysfunction. Following a discussion of evidence to support these mechanistic roles, we provide a brief discussion of potential complications of heparin usage in aSAH. Our review suggests that heparin’s use in aSAH is not only safe, but effectively addresses a number of pathologies initiated by aSAH.

  6. Neutralisation of the anti-coagulant effects of heparin by histones in blood plasma and purified systems.

    Science.gov (United States)

    Longstaff, Colin; Hogwood, John; Gray, Elaine; Komorowicz, Erzsebet; Varjú, Imre; Varga, Zoltán; Kolev, Krasimir

    2016-03-01

    Neutrophil extracellular traps (NETs) composed primarily of DNA and histones are a link between infection, inflammation and coagulation. NETs promote coagulation and approaches to destabilise NETs have been explored to reduce thrombosis and treat sepsis. Heparinoids bind histones and we report quantitative studies in plasma and purified systems to better understand physiological consequences. Unfractionated heparin (UFH) was investigated by activated partial thromboplastin time (APTT) and alongside low-molecular-weight heparins (LMWH) in purified systems with thrombin or factor Xa (FXa) and antithrombin (AT) to measure the sensitivity of UFH or LMWH to histones. A method was developed to assess the effectiveness of DNA and non-anticoagulant heparinoids as anti-histones. Histones effectively neutralised UFH, the IC50 value for neutralisation of 0.2 IU/ml UFH was 1.8 µg/ml histones in APTT and 4.6 µg/ml against 0.6 IU/ml UFH in a purified system. Histones also inhibited the activities of LMWHs with thrombin (IC50 6.1 and 11.0 µg/ml histones, for different LMWHs) or FXa (IC50 7.8 and 7.0 µg/ml histones). Direct interactions of UFH and LMWH with DNA and histones were explored by surface plasmon resonance, while rheology studies showed complex effects of histones, UFH and LMWH on clot resilience. A conclusion from these studies is that anticoagulation by UFH and LMWH will be compromised by high affinity binding to circulating histones even in the presence of DNA. A complete understanding of the effects of histones, DNA and heparins on the haemostatic system must include an appreciation of direct effects on fibrin and clot structure.

  7. An Epidermal Biosensor for Carcinoembryonic Antigen

    National Research Council Canada - National Science Library

    Schwartz, Pauline

    2001-01-01

    ...). An epidermal biosensor is a new approach for the early continuous, in vivo detection of the onset of disease by the using genetically modified skin cells to respond to molecules secreted by tumor cells...

  8. An Epidermal Biosensor for Carcinoembryonic Antigen

    National Research Council Canada - National Science Library

    Schwartz, Pauline

    2003-01-01

    ...) An epidermal biosensor was conceived as a new approach for the early continuous, in vivo detection of the onset of disease by the using genetically modified skin cells to respond to molecules secreted by tumor cells...

  9. Epidermal growth factor in the rat prostate

    DEFF Research Database (Denmark)

    Tørring, Niels; Jørgensen, P E; Poulsen, Steen Seier

    1998-01-01

    Epidermal growth factor (EGF) induces proliferation in prostate epithelial and stromal cells in primary culture. This investigation was set up to characterize the time and spatial expression of EGF in the rat prostate.......Epidermal growth factor (EGF) induces proliferation in prostate epithelial and stromal cells in primary culture. This investigation was set up to characterize the time and spatial expression of EGF in the rat prostate....

  10. Foliar Epidermal Studies of Plants in Euphorbiaceae

    Directory of Open Access Journals (Sweden)

    H. A. Thakur

    2014-03-01

    Full Text Available This paper describes foliar epidermal structure in 17 species belonging to 17 genera of the family Euphoprbiaceae. Anomocytic stomata is predominant, rarely they are anisocytic, paracytic on the same foliar surface with different combinations. Leaves are hypostomatic and rarely amphistomatic. The foliar surface is smooth, rarely striated. The foliar epidermal cell walls are straight or undulate. Distribution of stomata, stomatal index, stomatal frequency, stomatal size and other cell wall contours are described in detail.

  11. Epidermal Inclusion Cysts of The Breast

    Directory of Open Access Journals (Sweden)

    Amir R. Motabar

    2009-02-01

    Full Text Available Epidermal inclusion cysts are uncommon in the breast, but the consequences can besevere when these cysts occur in the breast parenchyma. Here,we report two suchcases. The patient in case 1 was an 37-year-old woman with a 3-cm palpable mass inthe right breast. Mammography revealed a round and smoothly outlined mass, whichindicated a benign tumor, and sonography showed an irregularly shaped and heterogeneoushypoechoic mass, fibroadenoma was suspected on the basis of clinical andimage findings, but excisional biopsy revealed an epidermal inclusion cyst. The patientin case 2 was a 50-year-old woman with a 2.5-cm lesion in the left breast. Mammographyrevealed a round, dense, smoothly outlined mass, and sonography showeda well-defined, central hyperechoic mass. . Breast cancer was suspected on the basisof the sonographic findings and the age of the patient, but the resected specimen revealedan epidermal inclusion cyst. Although epidermal inclusion cysts are benign,occasionally they may play a role in the origin of squamous carcinoma of the breast. .Mammographic and sonographic features of an epidermal cyst may mimic a malignantlesion. Malignant change appears to occur more frequently in epidermal inclusioncysts in the mammary gland, compared to common epidermal inclusion cysts,and this may be associated with origination of mammary epidermal inclusion cystsfrom squamous metaplasia of the mammary duct epithelium.Epidermmoid inclusion cyst of the breast is potentially serious, although such cystsare rare, and differentiation from a malignant or benign breast tumor is required. Excisionis probably the most appropriate treatment, and can eliminate the possible riskof malignant transformation.

  12. Extracellular matrix inspired surface functionalization with heparin, fibronectin and VEGF provides an anticoagulant and endothelialization supporting microenvironment

    International Nuclear Information System (INIS)

    Wang, Xue; Liu, Tao; Chen, Yuan; Zhang, Kun; Maitz, Manfred F.; Pan, Changjiang; Chen, Junying; Huang, Nan

    2014-01-01

    Highlights: • Surface modification with fibronectin, heparin and VEGF could selectively anticoagulant and promote endothelialization. • The bioactivity of biomolecules was more efficiently maintained via specific intermolecular interaction. • Poly-l-lysine interlayer was more feasible and the degradation product had no harm to human body. - Abstract: The biocompatibility of currently used coronary artery stent is still far from perfect, which closely related to insufficient endothelialization and thrombus formation. In this study, heparin, fibronectin and VEGF were immobilized on Ti surface to construct a multifunctional microenvironment with favorable properties to inhibit thrombosis formation and promote endothelialization simultaneously. The microenvironment on Ti surface was characterized in detail and demonstrated that the Hep/Fn/VEGF biofunctional coating was constructed successfully on Ti surface. The influence of surface properties such as chemical composition, roughness, hydrophilicity, and binding density of biomolecules on the performances of hemocompatibility and cytocompatibility was evaluated and discussed. Modified surface significantly enhanced the AT III binding density and prolonged the clotting time. In vitro platelet adhesion and activation assays further proved that the modified surface presented favorable anti-coagulant property. In addition, the proliferation of endothelial progenitor cells (EPCs) and endothelial cells (ECs) on the Hep/Fn/VEGF biofunctional coating was significantly promoted. In conclusion, the Hep/Fn/VEGF biofunctional coating was successfully constructed with desirable anticoagulant and endothelialization supporting properties. This work may provide a promising approach for biofunctional surface modification of coronary artery stent to acquire a desired multifunctional microenvironment

  13. Sensitive and selective turn off-on fluorescence detection of heparin based on the energy transfer platform using the BSA-stabilized Au nanoclusters/amino-functionalized graphene oxide hybrids.

    Science.gov (United States)

    Lan, Jing; Zou, Hong Yan; Wang, Qiang; Zeng, Ping; Li, Yuan Fang; Huang, Cheng Zhi

    2016-12-01

    An ultra-sensitive and selective turn off-on fluorescence detection of heparin based on the energy transfer in the BSA-stabilized gold nanoclusters/amino-functionalized graphene oxide (BSA-AuNCs/NH 2 -GO) hybrids was successfully realized. The BSA-AuNCs containing amounts of carboxyl groups could be absorbed on the surface of NH 2 -GO through the electrostatic interaction, which resulted in the fluorescence quenching of BSA-AuNCs with high efficiency. However, heparin, possessing high density of negative charge, could compete with BSA-AuNCs to bind NH 2 -GO and block the energy transfer from BSA-AuNCs to NH 2 -GO. The fluorescence recovery of BSA-AuNCs was closely related to the amount of heparin and there was a good linear relationship between fluorescence recovery of BSA-AuNCs and heparin over the range of 100ng/mL to 30μg/mL with a detection limit of 40ng/mL. What's more, the fluorescence assay was successfully applied for heparin sensing in human serums and intracellular imaging. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. The regulatory role of heparin on c-Met signaling in hepatocellular carcinoma cells.

    Science.gov (United States)

    İşcan, Evin; Güneş, Aysim; Korhan, Peyda; Yılmaz, Yeliz; Erdal, Esra; Atabey, Neşe

    2017-06-01

    The role of heparin as an anticoagulant is well defined; however, its role in tumorigenesis and tumor progression is not clear yet. Some studies have shown that anticoagulant treatment in cancer patients improve overall survival, however, recent clinical trials have not shown a survival benefit in cancer patients receiving heparin treatment. In our previous studies we have shown the inhibitory effects of heparin on Hepatocyte Growth Factor (HGF)-induced invasion and migration in hepatocellular carcinoma (HCC) cells. In this study, we showed the differential effects of heparin on the behaviors of HCC cells based on the presence or absence of HGF. In the absence of HGF, heparin activated HGF/c-Met signaling and promoted motility and invasion in HCC cells. Heparin treatment led to c-Met receptor dimerization and activated c-Met signaling in an HGF independent manner. Heparin-induced c-Met activation increased migration and invasion through ERK1/2, early growth response factor 1 (EGR1) and Matrix Metalloproteinases (MMP) axis. Interestingly, heparin modestly decreased the proliferation of HCC cells by inhibiting activatory phosphorylation of Akt. The inhibition of c-Met signaling reversed heparin-induced increase in motility and invasion and, proliferation inhibition. Our study provides a new perspective into the role of heparin on c-Met signaling in HCC.

  15. Voltammetric determination of heparin based on its interaction with ...

    African Journals Online (AJOL)

    ... with the linear regression equation as ∆ip″ (nA) = 360.19 C (mg/L) + 178.88 (n = 15, γ = 0.998) and the detection limit as 0.28 mg/L (3σ). The effects of coexisting substances such as metal ions, amino acids on the determination of heparin were investigated and the results showed that this method had good selectivity.

  16. Protein interactions with quaternized chitosan/heparin multilayers

    Czech Academy of Sciences Publication Activity Database

    Kumorek, Marta M.; Kubies, Dana; Riedel, Tomáš

    2016-01-01

    Roč. 65, Suppl. 2 (2016), S253-S261 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) LQ1604 Institutional support: RVO:61389013 Keywords : heparin * chitosan * protein Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.461, year: 2016 http://www.biomed.cas.cz/physiolres/pdf/65%20Suppl%202/65_S253.pdf

  17. Heparin defends against the toxicity of circulating histones in sepsis.

    Science.gov (United States)

    Wang, Feifei; Zhang, Naipu; Li, Biru; Liu, Lanbo; Ding, Lei; Wang, Ying; Zhu, Yimin; Mo, Xi; Cao, Qing

    2015-06-01

    Although circulating histones were demonstrated as major mediators of death in septic mice models, their roles in septic patients are not clarified. The present study sought to evaluate the clinical relevance of the circulating histone levels in septic children, and the antagonizing effects of heparin on circulating histones. Histone levels in the plasma of septic children were significantly higher than healthy controls, and positively correlated with disease severity. Histone treatment could activate NF-κB pathway of the endothelial cells and induce the secretion of large amount of cytokines that further amplify inflammation, subsequently leading to organ damage. Co-injection of low dose heparin with lethal dose histones could protect mouse from organ damage and death by antagonizing circulating histones, and similar effects were also observed in other septic models. Collectively, these findings indicated that circulating histones might serve as key factors in the pathogenesis of sepsis and their levels in plasma might be a marker for disease progression and prognosis. Furthermore, low dose heparin might be an effective therapy to hamper sepsis progression and reduce the mortality.

  18. The Use of Heparin during Endovascular Peripheral Arterial Interventions: A Synopsis

    Directory of Open Access Journals (Sweden)

    Arno M. Wiersema

    2016-01-01

    Full Text Available A large variety exists for many aspects of the use of heparin as periprocedural prophylactic antithrombotics (PPAT during peripheral arterial interventions (PAI. This variation is present, not only within countries, but also between them. Due to a lack of (robust data, no systematic review on the use of heparin during PAI could be justified. A synopsis of all available literature on heparin during PAI describes that heparin is used on technical equipment to reduce the thrombogenicity and in the flushing solution with saline. Heparin could have a cumulative anticoagulant effect when used in combination with ionic contrast medium. No level-1 evidence exists on the use of heparin. A measurement of actual anticoagulation status by means of an activated clotting time should be mandatory.

  19. Qualitative and Quantitative Analysis of Heparin during Precipitation by Near-Infrared Spectroscopy

    OpenAIRE

    Lian Li; Jinfeng Wang; Hengchang Zang; Hui Zhang; Wei Jiang; Shang Chen; Fengshan Wang

    2016-01-01

    Heparin is a glycosaminoglycan (GAG) that plays an important role in the blood coagulation system. Its quality is of great importance, so it is necessary to develop a fast analytical method during the manufacture process to analyse the quality of heparin produced. In this study, the heparin contents of 80 samples collected from five batches during the precipitation process were analysed using nearinfrared (NIR) spectroscopy and a chemometrics approach. This was done in order to improve the ef...

  20. Epidermal growth factor receptor in primary human lung cancer

    International Nuclear Information System (INIS)

    Yu Xueyan; Hu Guoqiang; Tian Keli; Wang Mingyun

    1996-01-01

    Cell membranes were prepared from 12 human lung cancers for the study of the expression of epidermal growth factor receptors (EGFR). EGFR concentration was estimated by ligand binding studies using 125 I-radiolabeled EGF. The dissociation constants of the high affinity sites were identical, 1.48 nmol and 1.1 nmol in cancer and normal lung tissues, the EGFR contents were higher in lung cancer tissues (range: 2.25 to 19.39 pmol·g -1 membrane protein) than that in normal tissues from the same patients (range: 0.72 to 7.43 pmol·g -1 membrane protein). These results suggest that EGF and its receptor may play a role in the regulatory mechanisms in the control of lung cellular growth and tumor promotion

  1. Epidermal growth factor pathway substrate 15, Eps15

    DEFF Research Database (Denmark)

    Salcini, A E; Chen, H; Iannolo, G

    1999-01-01

    Eps15 was originally identified as a substrate for the kinase activity of the epidermal growth factor receptor (EGFR). Eps15 has a tripartite structure comprising a NH2-terminal portion, which contains three EH domains, a central putative coiled-coil region, and a COOH-terminal domain containing...... multiple copies of the amino acid triplet Aspartate-Proline-Phenylalanine. A pool of Eps15 is localized at clathrin coated pits where it interacts with the clathrin assembly complex AP-2 and a novel AP-2 binding protein, Epsin. Perturbation of Eps15 and Epsin function inhibits receptor-mediated endocytosis...... of EGF and transferrin, demonstrating that both proteins are components of the endocytic machinery. Since the family of EH-containing proteins is implicated in various aspects of intracellular sorting, biomolecular strategies aimed at interfering with these processes can now be envisioned...

  2. Analysis of E2F factors during epidermal differentiation.

    Science.gov (United States)

    Chang, Wing Y; Dagnino, Lina

    2005-01-01

    The multigene E2F family of transcription factors is central in the control of cell cycle progression. The expression and activity of E2F proteins is tightly regulated transcriptionally and posttranslationally as a function of the proliferation and differentiation status of the cell. In this chapter, we review protocols designed to determine E2F mRNA abundance in tissues by in situ hybridization techniques. The ability to culture primary epidermal keratinocytes and maintain them as either undifferentiated or terminally differentiated cells allows the biochemical and molecular characterization of changes in E2F expression and activity. Thus, we also discuss in detail methods to analyze E2F protein abundance by immunoblot and their ability to bind DNA in cultured cells using electrophoretic mobility shift assays.

  3. From Farm to Pharma: An Overview of Industrial Heparin Manufacturing Methods.

    Science.gov (United States)

    van der Meer, Jan-Ytzen; Kellenbach, Edwin; van den Bos, Leendert J

    2017-06-21

    The purification of heparin from offal is an old industrial process for which commercial recipes date back to 1922. Although chemical, chemoenzymatic, and biotechnological alternatives for this production method have been published in the academic literature, animal-tissue is still the sole source for commercial heparin production in industry. Heparin purification methods are closely guarded industrial secrets which are not available to the general (scientific) public. However by reviewing the academic and patent literature, we aim to provide a comprehensive overview of the general methods used in industry for the extraction of heparin from animal tissue.

  4. Heparin and insulin in the management of hypertriglyceridemia-associated pancreatitis: case series and literature review.

    Science.gov (United States)

    Kuchay, Mohammad Shafi; Farooqui, Khalid J; Bano, Tarannum; Khandelwal, Manoj; Gill, Harmandeep; Mithal, Ambrish

    2017-01-01

    Severe hypertriglyceridemia accounts for up to 7% of all cases of acute pancreatitis. Heparin and insulin activate lipoprotein lipase (LPL), thereby reducing plasma triglyceride levels. However, the safety and efficacy of heparin and insulin in the treatment of hypertriglyceridemia-associated acute pancreatitis have not been well established yet. We successfully used heparin and insulin as first-line therapy in four consecutive patients with acute pancreatitis secondary to hypertriglyceridemia. In a literature search, we revised almost all reports published to date of patients managed successfully with this combination. Heparin and insulin appear to be a safe, effective, and inexpensive first-line therapy for hypertriglyceridemia-associated acute pancreatitis.

  5. Evidence-based algorithm for heparin dosing before cardiopulmonary bypass. Part 1: Development of the algorithm.

    Science.gov (United States)

    McKinney, Mark C; Riley, Jeffrey B

    2007-12-01

    The incidence of heparin resistance during adult cardiac surgery with cardiopulmonary bypass has been reported at 15%-20%. The consistent use of a clinical decision-making algorithm may increase the consistency of patient care and likely reduce the total required heparin dose and other problems associated with heparin dosing. After a directed survey of practicing perfusionists regarding treatment of heparin resistance and a literature search for high-level evidence regarding the diagnosis and treatment of heparin resistance, an evidence-based decision-making algorithm was constructed. The face validity of the algorithm decisive steps and logic was confirmed by a second survey of practicing perfusionists. The algorithm begins with review of the patient history to identify predictors for heparin resistance. The definition for heparin resistance contained in the algorithm is an activated clotting time 450 IU/kg heparin loading dose. Based on the literature, the treatment for heparin resistance used in the algorithm is anti-thrombin III supplement. The algorithm seems to be valid and is supported by high-level evidence and clinician opinion. The next step is a human randomized clinical trial to test the clinical procedure guideline algorithm vs. current standard clinical practice.

  6. Identification of a novel structure in heparin generated by potassium permanganate oxidation

    Science.gov (United States)

    Beccati, Daniela; Roy, Sucharita; Yu, Fei; Gunay, Nur Sibel; Capila, Ishan; Lech, Miroslaw; Linhardt, Robert J.; Venkataraman, Ganesh

    2012-01-01

    The worldwide heparin contamination crisis in 2008 led health authorities to take fundamental steps to better control heparin manufacture, including implementing appropriate analytical and bio-analytical methods to ensure production and release of high quality heparin sodium product. Consequently, there is an increased interest in the identification and structural elucidation of unusually modified structures that may be present in heparin. Our study focuses on the structural elucidation of species that give rise to a signal observed at 2.10 ppm in the N-acetyl region of the 1H NMR spectrum of some pharmaceutical grade heparin preparations. Structural elucidation experiments were carried out using homonuclear (COSY, TOSCY and NOESY) and heteronuclear (HSQC, HSQC-DEPT, HMQC-COSY, HSQC-TOCSY, and HMBC) 2D NMR spectroscopy on both heparin as well as heparin-like model compounds. Our results identify a novel type of oxidative modification of the heparin chain that results from a specific step in the manufacturing process used to prepare heparin. PMID:25147414

  7. The DP-1 transcription factor is required for keratinocyte growth and epidermal stratification.

    Science.gov (United States)

    Chang, Wing Y; Bryce, Dawn M; D'Souza, Sudhir J A; Dagnino, Lina

    2004-12-03

    The epidermis is a stratified epithelium constantly replenished through the ability of keratinocytes in its basal layer to proliferate and self-renew. The epidermis arises from a single-cell layer ectoderm during embryogenesis. Large proliferative capacity is central to ectodermal cell and basal keratinocyte function. DP-1, a heterodimeric partner of E2F transcription factors, is highly expressed in the ectoderm and all epidermal layers during embryogenesis. To investigate the role of DP-1 in epidermal morphogenesis, we inhibited DP-1 activity through exogenous expression of a dominant-negative mutant (dnDP-1). Expression of the dnDP-1 mutant interferes with binding of E2F/DP-1 heterodimers to DNA and inhibits DNA replication, as well as cyclin A mRNA and protein expression. Chromatin immunoprecipitation analysis demonstrated that the cyclin A promoter is predominantly bound in proliferating keratinocytes by complexes containing E2F-3 and E2F-4. Thus, the mechanisms of decreased expression of cyclin A in the presence of dnDP-1 seem to involve inactivation of DP-1 complexes containing E2F-3 and E2F-4. To assess the consequences on epidermal morphogenesis of inhibiting DP-1 activity, we expressed dnDP-1 in rat epithelial keratinocytes in organotypic culture and observed that DP-1 inhibition negatively affected stratification of these cells. Likewise, expression of dnDP-1 in embryonic ectoderm explants produced extensive disorganization of subsequently formed epidermal basal and suprabasal layers, interfering with normal epidermal formation. We conclude that DP-1 activity is required for normal epidermal morphogenesis and ectoderm-to-epidermis transition.

  8. Epidermal growth factor and its receptors in human pancreatic carcinoma

    International Nuclear Information System (INIS)

    Chen, Y.F.; Pan, G.Z.; Hou, X.; Liu, T.H.; Chen, J.; Yanaihara, C.; Yanaihara, N.

    1990-01-01

    The role of epidermal growth factor (EGF) in oncogenesis and progression of malignant tumors is a subject of vast interest. In this study, radioimmunoassay and radioreceptor assay of EGF were established. EGF contents in malignant and benign pancreatic tumors, in normal pancreas tissue, and in culture media of a human pancreatic carcinoma cell line were determined. EGF receptor binding studies were performed. It was shown that EGF contents in pancreatic carcinomas were significantly higher than those in normal pancreas or benign pancreatic tumors. EGF was also detected in the culture medium of a pancreatic carcinoma cell line. The binding of 125I-EGF to the pancreatic carcinoma cells was time and temperature dependent, reversible, competitive, and specific. Scatchard analysis showed that the dissociation constant of EGF receptor was 2.1 X 10(-9) M, number of binding sites was 1.3 X 10(5) cell. These results indicate that there is an over-expression of EGF/EGF receptors in pancreatic carcinomas, and that an autocrine regulatory mechanism may exist in the growth-promoting effect of EGF on tumor cells

  9. Microneedle fractional radiofrequency increases epidermal hyaluronan and reverses age-related epidermal dysfunction.

    Science.gov (United States)

    Lee, Hee Jung; Seo, Seong Rak; Yoon, Moon Soo; Song, Ji-Ye; Lee, Eun Young; Lee, Sang Eun

    2016-02-01

    Skin aging results in physiological alterations in keratinocyte activities and epidermal function, as well as dermal changes. Yet, the cellular and molecular mechanisms that cause epidermal dysfunction during skin aging are not well understood. Recently, the role of epidermal hyaluronan (HA) as an active regulator of dynamic cellular processes is getting attention and alterations in HA metabolism are thought to be important in age-related epidermal dysfunction. Microneedle fractional radiofrequency (RF) has shown effects for improving cutaneous aging. However, little is known about the effects of fractional RF on the epidermal HA and epidermal function. We investigated the effect of microneedle fractional RF on the expression of epidermal HA in young and aged mice epidermis. We performed fractional RF on the dorsal skin of 30 8-week-old (young) hairless mice and 15 47-week-old (aged) C57BL/6J mice. Skin samples were collected on day 1, 3, and 7. HA content was measured by ELISA. Gene expressions of CD 44, HABP4, and HAS3 were measured using real time RT-PCR. Immunohistochemistry for detection of HA, CD44, PCNA, and filaggrin were performed. HA content and the mRNA levels of HABP4, CD44, and HAS3 were upregulated in the epidermis of both young and aged mice after microneedle fractional RF treatment. The expression was increased from day 1 after treatment and increased expression persisted on day 7. Fractional RF treatment significantly increased PCNA and filaggrin expression only in the aged mice skin. Microneedle fractional RF increased epidermal HA and CD44 expression in both young and aged mice and reversed age-related epidermal dysfunction especially in aged mice, suggesting a new mechanism involved in the skin rejuvenation effect of microneedle fractional RF. © 2015 Wiley Periodicals, Inc.

  10. Compromised epidermal barrier stimulates Harderian gland activity and hypertrophy in ACBP-/- mice

    DEFF Research Database (Denmark)

    Sørensen, Signe Bek; Neess, Ditte; Dixen, Karen

    2015-01-01

    of the eye lid. We show that disruption of the Acbp gene leads to a significant enlargement of this gland with hypertrophy of the acinar cells and increased de novo synthesis of monoalkyl diacylglycerol, the main lipid species produced by the gland. Mice with conditional targeting of the Acbp gene......Acyl-CoA binding protein (ACBP) is a small, ubiquitously expressed intracellular protein that binds C14-C22 acyl-CoA esters with very high affinity and specificity. We have recently shown that targeted disruption of the Acbp gene leads to a compromised epidermal barrier and that this causes delayed...

  11. Covalent co-immobilization of heparin/laminin complex that with different concentration ratio on titanium surface for selectively direction of platelets and vascular cells behavior

    International Nuclear Information System (INIS)

    Wang, Jian; Chen, Yuan; Liu, Tao; Wang, Xue; Liu, Yang; Wang, Yuan; Chen, Junying; Huang, Nan

    2014-01-01

    Highlights: • Extracellular matrix inspired surface modification with fibronectin, heparin and VEGF to construct a favorable microenvironment for selectively anticoagulant and promote endothelialization. • Take the advantage of specific intermolecular interaction, the bioactivity of above biomolecules was more efficiently maintained in compared with the common used covalent immobilization method. • Poly-l-lysine was used as a novel interlayer for surface amination, and in comparison, PLL coating was more feasible and the degradation product had no harm to human body. - Abstract: Surface biofunctional modification of coronary artery stent to improve the hemocompatibility and selectively accelerate endothelium regeneration but prevent restenosis have been become a new hotspot. For this, a novel method was developed in this work by co-immobilization of Ln and heparin complex on poly-L-lysine modified Ti surface. Take the advantage of the specific interaction between Ln and heparin, Ln and heparin complexes with different concentration ratios were set up for creating different exposure density of these two types of biomolecules. According to biocompatibility evaluation results, the Hep/Ln complexes modified surface displayed less platelet adhesion and activation. Especially, on L(150)H and L(200)H surface, the AT III binding quantity, APTT value and anti-coagulation property of modified surface were significantly promoted. Furthermore, the adherent density and proliferation activity of ECs and EPCs were positively correlated with Ln concentration. Notably, the proliferation of both ECs and EPCs on L(100)H, L(150)H and L(200)H surface were greatly promoted. Another hand, the proliferation activity of SMCs was significantly inhibited on Hep/Ln modified surfaces, which was considered mainly due to the inhibitory effect of heparin to SMCs. According to the existing results, this study demonstrated that in a certain range of heparin and laminin concentration ratio

  12. Vitamin K antagonists or low-molecular-weight heparin for the long term treatment of symptomatic venous thromboembolism

    NARCIS (Netherlands)

    van der Heijden, J. F.; Hutten, B. A.; Büller, H. R.; Prins, M. H.

    2002-01-01

    BACKGROUND: People with venous thromboembolism are generally treated for five days with intravenous unfractionated heparin or subcutaneous low-molecular-weight heparin followed by three months of vitamin K antagonists treatment. Treatment with vitamin K antagonists requires regular laboratory

  13. EPIDERMAL MORPHOLOGY OF WEST AFRICAN OKRA ...

    African Journals Online (AJOL)

    Administrator

    stem peels were obtained from a slight cut on the tenth internodes. Peels from fruit ... xia l su rfa ce. A b a xia l su rfa ce. Adaxial surface. Abaxial surface. L e n g th. (µ m. ) ..... Variations in epidermal cell shape of both adaxial and abaxial surfaces ...

  14. FOLIAR EPIDERMAL AND PHYTOCHEMICAL STUDIES OF THE ...

    African Journals Online (AJOL)

    Administrator

    alkaloid, saponin, inulin, cellulose, tannin and lignin; Eragrostis tremula tested negative for lignin and positive for cellulose, saponin and alkaloids while Axonopus compressus tested negative for lignin, but positive for alkaloid, saponin, inulin, cellulose and tannin respectively. Leaf epidermal studies help to determine ...

  15. Stevens Johnsons syndrom og toksisk epidermal nekrolyse

    DEFF Research Database (Denmark)

    Kaur-Knudsen, Diljit; Zachariae, Claus; Thomsen, Simon Francis

    2013-01-01

    Stevens-Johnson syndrome and toxic epidermal necrolysis are acute mucocutaneous diseases primarily due to drug intake. The diseases are characterised by the separation of epidermis from dermis which can be life-threatening. Mortality is often caused by sepsis and multiple organ failure. The most...

  16. Interaction of the amyloid precursor protein-like protein 1 (APLP1) E2 domain with heparan sulfate involves two distinct binding modes

    Energy Technology Data Exchange (ETDEWEB)

    Dahms, Sven O., E-mail: sdahms@fli-leibniz.de [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany); Mayer, Magnus C. [Freie Universität Berlin, Thielallee 63, 14195 Berlin (Germany); Miltenyi Biotec GmbH, Robert-Koch-Strasse 1, 17166 Teterow (Germany); Roeser, Dirk [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany); Multhaup, Gerd [McGill University Montreal, Montreal, Quebec H3G 1Y6 (Canada); Than, Manuel E., E-mail: sdahms@fli-leibniz.de [Leibniz Institute for Age Research (FLI), Beutenbergstrasse 11, 07745 Jena (Germany)

    2015-03-01

    Two X-ray structures of APLP1 E2 with and without a heparin dodecasaccharide are presented, revealing two distinct binding modes of the protein to heparan sulfate. The data provide a mechanistic explanation of how APP-like proteins bind to heparan sulfates and how they specifically recognize nonreducing structures of heparan sulfates. Beyond the pathology of Alzheimer’s disease, the members of the amyloid precursor protein (APP) family are essential for neuronal development and cell homeostasis in mammals. APP and its paralogues APP-like protein 1 (APLP1) and APP-like protein 2 (APLP2) contain the highly conserved heparan sulfate (HS) binding domain E2, which effects various (patho)physiological functions. Here, two crystal structures of the E2 domain of APLP1 are presented in the apo form and in complex with a heparin dodecasaccharide at 2.5 Å resolution. The apo structure of APLP1 E2 revealed an unfolded and hence flexible N-terminal helix αA. The (APLP1 E2){sub 2}–(heparin){sub 2} complex structure revealed two distinct binding modes, with APLP1 E2 explicitly recognizing the heparin terminus but also interacting with a continuous heparin chain. The latter only requires a certain register of the sugar moieties that fits to a positively charged surface patch and contributes to the general heparin-binding capability of APP-family proteins. Terminal binding of APLP1 E2 to heparin specifically involves a structure of the nonreducing end that is very similar to heparanase-processed HS chains. These data reveal a conserved mechanism for the binding of APP-family proteins to HS and imply a specific regulatory role of HS modifications in the biology of APP and APP-like proteins.

  17. Assessment of HIT Antibody Complex in Hip Fracture Patients Receiving Enoxaparin or Unfractionated Heparin

    DEFF Research Database (Denmark)

    Griffin, Justin W; Hopkinson, William J; Rud-Lassen, Michael

    2011-01-01

    of antiheparin-PF4 antibodies and a greater prevalence of immunoglobulin G (IgG) subtype. Heparin and enoxaparin are capable of generating heparin-induced thrombocytopenia (HIT) antibodies in elderly patients undergoing orthopedic surgery but perhaps not to the same extent. When comparing low...

  18. Heparin induced alterations in clearance and distribution of blood-borne microparticles following operative trauma.

    Science.gov (United States)

    Saba, T M; Antikatzides, T G

    1979-04-01

    The influence of systemic heparin administration on the vascular clearance and tissue distribution of blood-borne microparticles was evaluated in normal rats and rats after operation (laparotomy plus intestinal manipulation) utilizing an (131)I- colloid which is phagocytized by the reticuloendothelial system (RES). Intravenous heparin administration (100 USP/100g body weight) into normal animals three minutes prior to colloid injection (50 mg/lOOg) induced a significant increase in pulmonary localization of the microparticles as compared to nonheparinized control rats, while hepatic and splenic uptake were decreased. Surgical trauma decreased hepatic RE uptake and increased pulmonary localization of the microparticles when injected systemically at 60 minutes postsurgery. Heparin administration 60 minutes after surgery and three minutes prior to colloid injection, magnified the increased pulmonary localization response with an associated further depression of the RES. The ability of heparin to alter both RE clearance function and lung localization of microparticles was dose dependent and a function of the interval between heparin administration and systemic particulate infusion. Thus, low dose heparin administration was capable of stimulating RE activity while heparin in doses of excess of 50 USP units/lOOg body weight decreased RE function. These findings suggest that the functional state of the hepatic RE system can be greatly affected in a dose-dependent manner by systemic heparin administration which may influence distribution of blood-borne microparticles.

  19. Covalently bound conjugates of albumin and heparin: Synthesis, fractionation and characterization

    NARCIS (Netherlands)

    Hennink, Wim E.; Feijen, Jan; Ebert, Charles D.; Kim, Sung Wan

    1983-01-01

    Covalently bound conjugates of human serum albumin and heparin were prepared as compounds which could improve the blood-compatibility of polymer surfaces either by preadsorption or by covalent coupling of the conjugates onto blood contacting surfaces. The conjugates (10–16 weight % of heparin) were

  20. Safety of low-molecular-weight heparin in pregnancy: a systematic review

    NARCIS (Netherlands)

    Sanson, B. J.; Lensing, A. W.; Prins, M. H.; Ginsberg, J. S.; Barkagan, Z. S.; Lavenne-Pardonge, E.; Brenner, B.; Dulitzky, M.; Nielsen, J. D.; Boda, Z.; Turi, S.; Mac Gillavry, M. R.; Hamulyák, K.; Theunissen, I. M.; Hunt, B. J.; Büller, H. R.

    1999-01-01

    Unfractionated heparin (UFH) remains the anticoagulant of choice during pregnancy. Low-molecular-weight heparins (LMWH) are an attractive alternative to UFH due to their logistic advantages and their association with a lower incidence of osteoporosis and HIT. We reviewed all published clinical

  1. Poly(vinyl alcohol)-heparin hydrogels as sensor catheter membranes

    NARCIS (Netherlands)

    Brinkman, E.; van der Does, L.; Bantjes, A.

    1991-01-01

    Poly(vinyl alcohol)-heparin hydrogels with varying water content were synthesized for use as sensor catheter membranes. Films were cast from aqueous mixtures of poly(viny) alcohol) (PVA), a photosensitive cross-linker p-diazonium diphenyl amine polymer (PA), glutaraldehyde (GA) and heparin. After

  2. Design of a new type of coating for the controlled release of heparin

    NARCIS (Netherlands)

    Hinrichs, W.L.J.; Hinrichs, W.L.J.; ten Hoopen, Hermina W.M.; Wissink, M.J.B.; Engbers, G.H.M.; Feijen, Jan

    1997-01-01

    Thrombus formation at the surface of blood contacting devices can be prevented by local release of heparin. Preferably, the release rate should be constant for prolonged periods of time. The minimum heparin release rate to achieve thromboresistance will be different for various applications and

  3. Anti-Platelet Factor 4/Heparin Antibody Formation Occurs Endogenously and at Unexpected High Frequency in Polycythemia Vera

    Directory of Open Access Journals (Sweden)

    Sara C. Meyer

    2017-01-01

    Full Text Available Background. Myeloproliferative neoplasms (MPN encounter thromboses due to multiple known risk factors. Heparin-induced thrombocytopenia (HIT is a thrombotic syndrome mediated by anti-platelet factor 4 (PF4/heparin antibodies with undetermined significance for thrombosis in MPN. We hypothesized that anti-PF4/heparin Ab might occur in MPN and promote thrombosis. Methods. Anti-PF4/heparin antibodies were analyzed in 127 MPN patients including 76 PV and 51 ET. Screening, validation testing, and isotype testing of anti-PF4/heparin Ab were correlated with disease characteristics. Results. Anti-PF4/heparin antibodies were detected in 21% of PV and 12% of ET versus 0.3–3% in heparin-exposed patients. Validation testing confirmed anti-PF4/heparin immunoglobulins in 15% of PV and 10% of ET. Isotype testing detected 9.2% IgG and 5.3% IgM in PV and exclusively IgM in ET. IgG-positive PV patients encountered thromboses in 57.1% suggesting anti-PF4/heparin IgG may contribute to higher risk for thrombosis in MPN. Overall, 45% of PV patients experienced thromboses with 11.8% positive for anti-PF4/heparin IgG versus 7.1% in PV without thrombosis. Conclusion. Anti-PF4/heparin antibodies occur endogenously and more frequently in MPN than upon heparin exposure. Thrombotic risk increases in anti-PF4/heparin IgG-positive PV reflecting potential implications and calling for larger, confirmatory cohorts. Anti-PF4/heparin IgG should be assessed upon thrombosis in PV to facilitate avoidance of heparin in anti-PF4/heparin IgG-positive PV.

  4. Heparinization of alimentation solutions administered through peripheral veins in premature infants: a controlled study.

    Science.gov (United States)

    Alpan, G; Eyal, F; Springer, C; Glick, B; Goder, K; Armon, J

    1984-09-01

    A randomized controlled study was done to determine whether the addition of heparin (1 U/mL) to peripheral intravenous alimentation solutions would affect the incidence of phlebitis and duration of patency of intravenous catheters in premature infants. Twenty-two-gauge Teflon catheters were uniformly used. One hundred five catheters infused with heparin were placed in 13 infants, and 122 catheters were placed in the control group of 13 infants. The time, nature, and incidence of complications were noted for each infusion site. Infusion of heparin was found to double the duration of patency of intravenous catheters and to reduce significantly the incidence of phlebitis. No complications related to the administration of heparin were noted. Heparinization of intravenous alimentation solutions should therefore be considered in premature infants as a means of reducing the work load and incidence of complications associated with peripheral lines.

  5. Heparin-Induced Cardiac Tamponade and Life-Threatening Hyperkalemia in a Patient with Chronic Hemodialysis

    Directory of Open Access Journals (Sweden)

    Ho-Ming Su

    2005-03-01

    Full Text Available Heparin, a commonly used anticoagulant agent, is frequently used in patients undergoing hemodialysis. As with most medications, heparin has a significant side effect profile. Two of its most important side effects, major bleeding and hyperkalemia, may be devastating without immediate diagnosis and treatment. Major bleeding such as gastrointestinal, genitourinary or intracranial bleeding is occasionally encountered and rarely neglected. However, heparin-induced cardiac tamponade is rarely encountered and may be easily overlooked. Another side effect, heparin-induced hyperkalemia, an unusual but well-described side effect, is frequently forgotten until life-threatening arrhythmia has occurred. We report a case involving a 40-year-old male patient with uremia, who had received heparin for 10 days for deep vein thrombosis in the left lower extremity. Hemopericardium with cardiac tamponade and life-threatening hyperkalemia were both noted in this patient.

  6. The US regulatory and pharmacopeia response to the global heparin contamination crisis.

    Science.gov (United States)

    Szajek, Anita Y; Chess, Edward; Johansen, Kristian; Gratzl, Gyöngyi; Gray, Elaine; Keire, David; Linhardt, Robert J; Liu, Jian; Morris, Tina; Mulloy, Barbara; Nasr, Moheb; Shriver, Zachary; Torralba, Pearle; Viskov, Christian; Williams, Roger; Woodcock, Janet; Workman, Wesley; Al-Hakim, Ali

    2016-06-09

    The contamination of the widely used lifesaving anticoagulant drug heparin in 2007 has drawn renewed attention to the challenges that are associated with the characterization, quality control and standardization of complex biological medicines from natural sources. Heparin is a linear, highly sulfated polysaccharide consisting of alternating glucosamine and uronic acid monosaccharide residues. Heparin has been used successfully as an injectable antithrombotic medicine since the 1930s, and its isolation from animal sources (primarily porcine intestine) as well as its manufacturing processes have not changed substantially since its introduction. The 2007 heparin contamination crisis resulted in several deaths in the United States and hundreds of adverse reactions worldwide, revealing the vulnerability of a complex global supply chain to sophisticated adulteration. This Perspective discusses how the US Food and Drug Administration (FDA), the United States Pharmacopeial Convention (USP) and international stakeholders collaborated to redefine quality expectations for heparin, thus making an important natural product better controlled and less susceptible to economically motivated adulteration.

  7. Interactions of oversulfated chondroitin sulfate (OSCS) from different sources with unfractionated heparin.

    Science.gov (United States)

    Gray, Angel; Litinas, Evangelos; Jeske, Walter; Fareed, Jawed; Hoppensteadt, Debra

    2012-01-01

    In 2008, oversulfated chondroitin sulfate (OSCS) was identified as the main contaminant in recalled heparin. Oversulfated chondroitin sulfate can be prepared from bovine (B), porcine (P), shark (Sh), or skate (S) origin and may produce changes in the antithrombotic, bleeding, and hemodynamic profile of heparins. This study examines the interactions of various OSCSs on heparin in animal models of thrombosis and bleeding, as well as on the anticoagulant and antiprotease effects in in vitro assays. Mixtures of 70% unfractionated heparin (UFH) with 30% OSCS from different sources were tested. In the in vitro activated partial thromboplastin time (aPTT) assay, all contaminant mixtures showed a decrease in clotting times. In addition, a significant increase in bleeding time compared to the control (UFH/saline) was observed. In the thrombosis model, no significant differences were observed. The OSCSs significantly increased anti-Xa activity in ex vivo blood samples. These results indicate that various sources of OSCS affect the hemostatic properties of heparin.

  8. Neratinib Reverses ATP-Binding Cassette B1-Mediated Chemotherapeutic Drug Resistance In Vitro, In Vivo, and Ex Vivo

    OpenAIRE

    Zhao, Xiao-qin; Xie, Jing-dun; Chen, Xing-gui; Sim, Hong May; Zhang, Xu; Liang, Yong-ju; Singh, Satyakam; Talele, Tanaji T.; Sun, Yueli; Ambudkar, Suresh V.; Chen, Zhe-Sheng; Fu, Li-wu

    2012-01-01

    Neratinib, an irreversible inhibitor of epidermal growth factor receptor and human epidermal receptor 2, is in phase III clinical trials for patients with human epidermal receptor 2-positive, locally advanced or metastatic breast cancer. The objective of this study was to explore the ability of neratinib to reverse tumor multidrug resistance attributable to overexpression of ATP-binding cassette (ABC) transporters. Our results showed that neratinib remarkably enhanced the sensitivity of ABCB1...

  9. Epidermal growth factor-mediated effects on equine vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Grosenbaugh, D.A.; Amoss, M.S.; Hood, D.M.; Morgan, S.J.; Williams, J.D.

    1988-01-01

    Epidermal growth factor (EGF) receptor binding kinetics and EGF-mediated stimulation of DNA synthesis and cellular proliferation were studied in cultured vascular smooth muscle cells (VSMC) from the equine thoracic aorta. Binding studies, using murine 125 I-labeled EGF, indicate the presence of a single class of high-affinity binding sites, with an estimated maximal binding capacity of 5,800 sites/cells. EGF stimulated [ 3 H]thymidine uptake in confluent quiescent monolayers in a dose-dependent fashion, half-maximal stimulation occurring at 7.5 x 10 -11 M. Likewise, EGF-mediated cellular proliferation was dose dependent under reduced serum concentrations. Equine VSMC contain specific receptors for EGF, and EGF can stimulate DNA synthesis and proliferation in these cultured cells, which suggests that EGF may participate in the proliferative changes observed in equine distal digital peripheral vascular disease

  10. How much heparin do we really need to go on pump? A rethink of current practices.

    LENUS (Irish Health Repository)

    Shuhaibar, M N

    2012-02-03

    OBJECTIVES: Patients undergoing myocardial revascularisation using extracorporeal circulation require heparin anticoagulation. We aimed to evaluate the effect of reducing heparin dosage on target activated clotting time (ACT) and postoperative blood loss. METHODS: In a prospective randomised trial, 195 patients undergoing isolated primary CABG were randomised into four groups A, B, C, and D receiving an initial heparin dosage of 100, 200, 250 and 300 iu\\/kg, respectively. Extra incremental heparin (50 iu\\/kg) was added if required to achieve a target ACT of 480 s before initiating cardiopulmonary bypass. Postoperative blood loss was measured from the time of heparin reversal to drain removal 24h later. RESULTS: Target ACT was achieved in 0, 63, 68.3 and 82.4% of patients in groups A, B, C and D, respectively, after the initial dose of heparin. In group B, of those not achieving target act a single increment of heparin was sufficient to achieve target ACT in further 18.6%. The mean ACT after the initial dose in groups B, C and D was 482.9, 519 and 588 s, respectively (P<0.05). Postoperative blood loss in millilitre per kilogram was directly proportional to preoperative heparin dose. CONCLUSIONS: Patients receiving lower dose of heparin has lower postoperative blood loss. Of those achieving the target ACT, group B was significantly the closest to the target ACT. A starting dose of 200 iu\\/kg of heparin and if necessary one 50 iu\\/kg increment achieved target ACT in 81.5% of patients. The added benefit of significant drop in postoperative blood loss is evident.

  11. Intravitreal low molecular weight heparin in PVR surgery.

    Directory of Open Access Journals (Sweden)

    Kumar Atul

    2003-01-01

    Full Text Available Purpose: To evaluate the efficacy of low molecular weight heparin (LMWH in prevention of postoperative fibrin formation following vitreoretinal surgery with proliferative vitreoretinopathy (PVR. Material and Methods: Thirty consecutive patients of retinal detachment with advanced PVR were enrolled in the study. They were randomised to study and control groups (n = 15 each. Study group patients received vitreoretinal surgery with 5 IU/cc of LMWH in vitrectomy infusion fluid. The control group patients received vitroretinal surgery without heparin in the infusion fluid. Patients were followed up at 1 week, 1 month and 3 months after surgery. Postoperative bleeding, media clarity, best-corrected visual acuity and success of the surgery at the end of 3 months were compared between the two groups. Results: At each follow-up visit, the study group showed a better media clarity, which was statistically significant ( P = 0.0042. The study group had a 50% better chance of retinal reattachment compared to the control group. Five patients had intraoperative bleeding in the study group (33% compared to 3 patients in the control group (20%. Conclusion: Use of intravitreal LMWH prevents postoperative fibrin formation and is beneficial in repair of retinal detachments with PVR.

  12. Multifunctional silk-heparin biomaterials for vascular tissue engineering applications

    Science.gov (United States)

    Seib, F. Philipp; Herklotz, Manuela; Burke, Kelly A.; Maitz, Manfred F.; Werner, Carsten; Kaplan, David L.

    2013-01-01

    Over the past 30 years, silk has been proposed for numerous biomedical applications that go beyond its traditional use as a suture material. Silk sutures are well tolerated in humans, but the use of silk for vascular engineering applications still requires extensive biocompatibility testing. Some studies have indicated a need to modify silk to yield a hemocompatible surface. This study examined the potential of low molecular weight heparin as a material for refining silk properties by acting as a carrier for vascular endothelial growth factor (VEGF) and improving silk hemocompatibility. Heparinized silk showed a controlled VEGF release over 6 days; the released VEGF was bioactive and supported the growth of human endothelial cells. Silk samples were then assessed using a humanized hemocompatibility system that employs whole blood and endothelial cells. The overall thrombogenic response for silk was very low and similar to the clinical reference material polytetrafluoroethylene. Despite an initial inflammatory response to silk, apparent as complement and leukocyte activation, the endothelium was maintained in a resting, anticoagulant state. The low thrombogenic response and the ability to control VEGF release support the further development of silk for vascular applications. PMID:24099708

  13. Backbone dynamics of a biologically active human FGF-1 monomer, complexed to a hexasaccharide heparin-analogue, by 15N NMR relaxation methods

    International Nuclear Information System (INIS)

    Canales-Mayordomo, Angeles; Fayos, Rosa; Angulo, Jesus; Ojeda, Rafael; Martin-Pastor, Manuel; Nieto, Pedro M.; Martin-Lomas, Manuel; Lozano, Rosa; Gimenez-Gallego, Guillermo; Jimenez-Barbero, Jesus

    2006-01-01

    The binding site and backbone dynamics of a bioactive complex formed by the acidic fibroblast growth factor (FGF-1) and a specifically designed heparin hexasaccharide has been investigated by HSQC and relaxation NMR methods. The comparison of the relaxation data for the free and bound states has allowed showing that the complex is monomeric, and still induces mutagenesis, and that the protein backbone presents reduced motion in different timescale in its bound state, except in certain points that are involved in the interaction with the fibroblast growth factor receptor (FGFR)

  14. Backbone dynamics of a biologically active human FGF-1 monomer, complexed to a hexasaccharide heparin-analogue, by {sup 15}N NMR relaxation methods

    Energy Technology Data Exchange (ETDEWEB)

    Canales-Mayordomo, Angeles; Fayos, Rosa [Centro de Investigaciones Biologicas, CSIC, Departamento de Estructura y Funcion de Proteinas (Spain); Angulo, Jesus; Ojeda, Rafael [Instituto de Investigaciones Quimicas, CSIC, Grupo de Carbohidratos (Spain); Martin-Pastor, Manuel [Unidad de RM y Unidad de RMN de Biomoleculas Asociada al CSIC, Laboratorio de Estructura e Estructura de Biomoleculas Jose Carracido (Spain); Nieto, Pedro M.; Martin-Lomas, Manuel [Instituto de Investigaciones Quimicas, CSIC, Grupo de Carbohidratos (Spain); Lozano, Rosa; Gimenez-Gallego, Guillermo; Jimenez-Barbero, Jesus [Centro de Investigaciones Biologicas, CSIC, Departamento de Estructura y Funcion de Proteinas (Spain)], E-mail: jjbarbero@cib.csic.es

    2006-08-15

    The binding site and backbone dynamics of a bioactive complex formed by the acidic fibroblast growth factor (FGF-1) and a specifically designed heparin hexasaccharide has been investigated by HSQC and relaxation NMR methods. The comparison of the relaxation data for the free and bound states has allowed showing that the complex is monomeric, and still induces mutagenesis, and that the protein backbone presents reduced motion in different timescale in its bound state, except in certain points that are involved in the interaction with the fibroblast growth factor receptor (FGFR)

  15. A peptide of heparin cofactor II inhibits endotoxin-mediated shock and invasive Pseudomonas aeruginosa infection.

    Directory of Open Access Journals (Sweden)

    Martina Kalle

    Full Text Available Sepsis and septic shock remain important medical problems with high mortality rates. Today's treatment is based mainly on using antibiotics to target the bacteria, without addressing the systemic inflammatory response, which is a major contributor to mortality in sepsis. Therefore, novel treatment options are urgently needed to counteract these complex sepsis pathologies. Heparin cofactor II (HCII has recently been shown to be protective against Gram-negative infections. The antimicrobial effects were mapped to helices A and D of the molecule. Here we show that KYE28, a 28 amino acid long peptide representing helix D of HCII, is antimicrobial against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, the Gram-positive Bacillus subtilis and Staphylococcus aureus, as well as the fungus Candida albicans. Moreover, KYE28 binds to LPS and thereby reduces LPS-induced pro-inflammatory responses by decreasing NF-κB/AP-1 activation in vitro. In mouse models of LPS-induced shock, KYE28 significantly enhanced survival by dampening the pro-inflammatory cytokine response. Finally, in an invasive Pseudomonas infection model, the peptide inhibited bacterial growth and reduced the pro-inflammatory response, which lead to a significant reduction of mortality. In summary, the peptide KYE28, by simultaneously targeting bacteria and LPS-induced pro-inflammatory responses represents a novel therapeutic candidate for invasive infections.

  16. An antimicrobial helix A-derived peptide of heparin cofactor II blocks endotoxin responses in vivo.

    Science.gov (United States)

    Papareddy, Praveen; Kalle, Martina; Singh, Shalini; Mörgelin, Matthias; Schmidtchen, Artur; Malmsten, Martin

    2014-05-01

    Host defense peptides are key components of the innate immune system, providing multi-facetted responses to invading pathogens. Here, we describe that the peptide GKS26 (GKSRIQRLNILNAKFAFNLYRVLKDQ), corresponding to the A domain of heparin cofactor II (HCII), ameliorates experimental septic shock. The peptide displays antimicrobial effects through direct membrane disruption, also at physiological salt concentration and in the presence of plasma and serum. Biophysical investigations of model lipid membranes showed the antimicrobial action of GKS26 to be mirrored by peptide incorporation into, and disordering of, bacterial lipid membranes. GKS26 furthermore binds extensively to bacterial lipopolysaccharide (LPS), as well as its endotoxic lipid A moiety, and displays potent anti-inflammatory effects, both in vitro and in vivo. Thus, for mice challenged with ip injection of LPS, GKS26 suppresses pro-inflammatory cytokines, reduces vascular leakage and infiltration in lung tissue, and normalizes coagulation. Together, these findings suggest that GKS26 may be of interest for further investigations as therapeutic against severe infections and septic shock. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. A peptide of heparin cofactor II inhibits endotoxin-mediated shock and invasive Pseudomonas aeruginosa infection.

    Science.gov (United States)

    Kalle, Martina; Papareddy, Praveen; Kasetty, Gopinath; van der Plas, Mariena J A; Mörgelin, Matthias; Malmsten, Martin; Schmidtchen, Artur

    2014-01-01

    Sepsis and septic shock remain important medical problems with high mortality rates. Today's treatment is based mainly on using antibiotics to target the bacteria, without addressing the systemic inflammatory response, which is a major contributor to mortality in sepsis. Therefore, novel treatment options are urgently needed to counteract these complex sepsis pathologies. Heparin cofactor II (HCII) has recently been shown to be protective against Gram-negative infections. The antimicrobial effects were mapped to helices A and D of the molecule. Here we show that KYE28, a 28 amino acid long peptide representing helix D of HCII, is antimicrobial against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, the Gram-positive Bacillus subtilis and Staphylococcus aureus, as well as the fungus Candida albicans. Moreover, KYE28 binds to LPS and thereby reduces LPS-induced pro-inflammatory responses by decreasing NF-κB/AP-1 activation in vitro. In mouse models of LPS-induced shock, KYE28 significantly enhanced survival by dampening the pro-inflammatory cytokine response. Finally, in an invasive Pseudomonas infection model, the peptide inhibited bacterial growth and reduced the pro-inflammatory response, which lead to a significant reduction of mortality. In summary, the peptide KYE28, by simultaneously targeting bacteria and LPS-induced pro-inflammatory responses represents a novel therapeutic candidate for invasive infections.

  18. Preparation of Low Molecular Weight Heparin by Microwave Discharge Electrodeless Lamp/TiO2 Photo-Catalytic Reaction.

    Science.gov (United States)

    Lee, Do-Jin; Kim, Byung Hoon; Kim, Sun-Jae; Kim, Jung-Sik; Lee, Heon; Jung, Sang-Chul

    2015-01-01

    An MDEL/TiO2 photo-catalyst hybrid system was applied, for the first time, for the production of low molecular weight heparin. The molecular weight of produed heparin decreased with increasing microwave intensity and treatment time. The abscission of the chemical bonds between the constituents of heparin by photo-catalytic reaction did not alter the characteristics of heparin. Formation of by-products due to side reaction was not observed. It is suggested that heparin was depolymerized by active oxygen radicals produced during the MDEL/TiO2 photo-chemical reaction.

  19. Epidermal CYP2 family cytochromes P450

    International Nuclear Information System (INIS)

    Du Liping; Hoffman, Susan M.G.; Keeney, Diane S.

    2004-01-01

    Skin is the largest and most accessible drug-metabolizing organ. In mammals, it is the competent barrier that protects against exposure to harmful stimuli in the environment and in the systemic circulation. Skin expresses many cytochromes P450 that have critical roles in exogenous and endogenous substrate metabolism. Here, we review evidence for epidermal expression of genes from the large CYP2 gene family, many of which are expressed preferentially in extrahepatic tissues or specifically in epithelia at the environmental interface. At least 13 CYP2 genes (CYP2A6, 2A7, 2B6, 2C9, 2C18, 2C19, 2D6, 2E1, 2J2, 2R1, 2S1, 2U1, and 2W1) are expressed in skin from at least some human individuals, and the majority of these genes are expressed in epidermis or cultured keratinocytes. Where epidermal expression has been localized in situ by hybridization or immunocytochemistry, CYP2 transcripts and proteins are most often expressed in differentiated keratinocytes comprising the outer (suprabasal) cell layers of the epidermis and skin appendages. The tissue-specific transcriptional regulation of CYP2 genes in the epidermis, and in other epithelia that interface with the environment, suggests important roles for at least some CYP2 gene products in the production and disposition of molecules affecting competency of the epidermal barrier

  20. Epidermal cell death in frogs with chytridiomycosis

    Directory of Open Access Journals (Sweden)

    Laura A. Brannelly

    2017-02-01

    Full Text Available Background Amphibians are declining at an alarming rate, and one of the major causes of decline is the infectious disease chytridiomycosis. Parasitic fungal sporangia occur within epidermal cells causing epidermal disruption, but these changes have not been well characterised. Apoptosis (planned cell death can be a damaging response to the host but may alternatively be a mechanism of pathogen removal for some intracellular infections. Methods In this study we experimentally infected two endangered amphibian species Pseudophryne corroboree and Litoria verreauxii alpina with the causal agent of chytridiomycosis. We quantified cell death in the epidermis through two assays: terminal transferase-mediated dUTP nick end-labelling (TUNEL and caspase 3/7. Results Cell death was positively associated with infection load and morbidity of clinically infected animals. In infected amphibians, TUNEL positive cells were concentrated in epidermal layers, correlating to the localisation of infection within the skin. Caspase activity was stable and low in early infection, where pathogen loads were light but increasing. In animals that recovered from infection, caspase activity gradually returned to normal as the infection cleared. Whereas, in amphibians that did not recover, caspase activity increased dramatically when infection loads peaked. Discussion Increased cell death may be a pathology of the fungal parasite, likely contributing to loss of skin homeostatic functions, but it is also possible that apoptosis suppression may be used initially by the pathogen to help establish infection. Further research should explore the specific mechanisms of cell death and more specifically apoptosis regulation during fungal infection.

  1. Cancer Cell Adhesion and Metastasis: Selectins, Integrins, and the Inhibitory Potential of Heparins

    Directory of Open Access Journals (Sweden)

    Gerd Bendas

    2012-01-01

    Full Text Available Cell adhesion molecules play a significant role in cancer progression and metastasis. Cell-cell interactions of cancer cells with endothelium determine the metastatic spread. In addition, direct tumor cell interactions with platelets, leukocytes, and soluble components significantly contribute to cancer cell adhesion, extravasation, and the establishment of metastatic lesions. Clinical evidence indicates that heparin, commonly used for treatment of thromboembolic events in cancer patients, is beneficial for their survival. Preclinical studies confirm that heparin possesses antimetastatic activities that lead to attenuation of metastasis in various animal models. Heparin contains several biological activities that may affect several steps in metastatic cascade. Here we focus on the role of cellular adhesion receptors in the metastatic cascade and discuss evidence for heparin as an inhibitor of cell adhesion. While P- and L-selectin facilitation of cellular contacts during hematogenous metastasis is being accepted as a potential target of heparin, here we propose that heparin may also interfere with integrin activity and thereby affect cancer progression. This review summarizes recent findings about potential mechanisms of tumor cell interactions in the vasculature and antimetastatic activities of heparin.

  2. Quantitative determination of heparin levels in serum with microtiter plate-format optode

    International Nuclear Information System (INIS)

    Kim, Sung Bae; Kang, Tae Young; Cha, Geun Sig; Nam, Hakhyun

    2006-01-01

    A new assay method has been developed for the quantitative determination of heparin in serum using a microtiter plate-format optode (MPO). Heparin and proton in physiological sample are favorably co-extracted into the solvent polymeric optode membrane containing both cationic lipophilic additive, tridodecylmethyl ammonium chloride (TDMAC), and proton-selective ionophore, 3-hydroxy-4-(4-nitrophenylazo)-phenyloctadecanoate (ETH 2412), resulting in the absorbance change of the membrane to varying heparin levels. The optimized MPO composition contains low polymer-to-plasticizer ratio compared to those of conventional ion-selective optodes or electrodes, i.e., poly(vinyl chloride) (20.0)/dioctylsebacate (76.3)/ETH 2412 (1.7)/TDMAC (1.0) (wt.%): it resulted in a quantitative response to heparin from 0 to 15 unit/mL in serum with high sensitivity. The heparin-protamine titration on the MPO could provide rapid and precise determination of heparin. It was shown that the heparin levels in serum sample could be determined from the rate of absorbance change over time (ΔA/Δt); this method was more effective than the direct absorbance measurement in minimizing the interferences from color and turbidity of serum samples. MPO has been developed as a high throughput and convenient disposable sensing device, and may find a wide application in the determination of polyions and charged macromolecules

  3. Heparin and glutathione II: correlation between decondensation of bull sperm cells and its nucleons.

    Science.gov (United States)

    Delgado, N M; Flores-Alonso, J C; Rodríguez-Hernández, H M; Merchant-Larios, H; Reyes, R

    2001-01-01

    The correlation between the kinetics of bull sperm nuclear and nucleon decondensation induced by the action of physiological concentrations of heparin/GSH was studied. Sperm and nucleon suspensions were incubated at 37 degrees C in salt medium, at a constant concentration of either heparin or GSH and increasing concentrations of the other reagent. Even though nucleons are pretreated with DTT/CTAB, when they are incubated alone with GSH for 96 h, they remain intact, no matter which concentration is employed, and it was impossible to observe the slightest sign of nuclei decondensation. Therefore, rupture of disulfide bridges is not the main mechanism to induce nuclei decondensation and perhaps the GSH role resides in potentate the heparin effect by increasing its negative charge. Nevertheless, nucleons reach 95% of chromatin decondensation in the presence of heparin plus GSH or heparin alone. The fact that the correlation between heparin and GSH concentrations needed to induce sperm nuclei decondensation was 3- to 4-fold greater that in nucleons might be due to the complete lack of nucleon membranes. Heparin/GSH seem to induce nuclei decondensation by an ionic chromatin charge neutralization mechanism.

  4. Heparin modulates human intestinal smooth muscle (HISM) cell proliferation and matrix production

    International Nuclear Information System (INIS)

    Graham, M.; Perr, H.; Drucker, D.E.; Diegelmann, R.F.

    1986-01-01

    (HISM) cell proliferation and collagen production may play a role in the pathogenesis of intestinal stricture in Crohn's disease. The present studies were performed to evaluate the effects of heparin, a known modulator of vascular smooth muscle cells, on HISM cell proliferation and collagen production. Heparin (100 μg/ml) was added daily to HISM cell cultures for cell proliferation studies and for 24 hours at various time points during culture for collagen synthesis studies. Collagen synthesis was determined by the uptake of 3 H proline into collagenase-sensitive protein. Heparin completely inhibited cell proliferation for 7 days, after which cell numbers increased but at a slower rate than controls. Cells released from heparin inhibition demonstrated catch-up growth to control levels. Collagen production was significantly inhibited by 24 hours exposure to heparin but only at those times during culture when collagen synthesis was maximal (8 to 12 days). Non-collagen protein synthesis was inhibited by heparin at all time points during culture. Heparin through its modulation of HISM cells may play an important role in the control of the extracellular matrix of the intestinal wall

  5. Nerve growth factor loaded heparin/chitosan scaffolds for accelerating peripheral nerve regeneration.

    Science.gov (United States)

    Li, Guicai; Xiao, Qinzhi; Zhang, Luzhong; Zhao, Yahong; Yang, Yumin

    2017-09-01

    Artificial chitosan scaffolds have been widely investigated for peripheral nerve regeneration. However, the effect was not as good as that of autologous grafts and therefore could not meet the clinical requirement. In the present study, the nerve growth factor (NGF) loaded heparin/chitosan scaffolds were fabricated via electrostatic interaction for further improving nerve regeneration. The physicochemical properties including morphology, wettability and composition were measured. The heparin immobilization, NGF loading and release were quantitatively and qualitatively characterized, respectively. The effect of NGF loaded heparin/chitosan scaffolds on nerve regeneration was evaluated by Schwann cells culture for different periods. The results showed that the heparin immobilization and NGF loading did not cause the change of bulk properties of chitosan scaffolds except for morphology and wettability. The pre-immobilization of heparin in chitosan scaffolds could enhance the stability of subsequently loaded NGF. The NGF loaded heparin/chitosan scaffolds could obviously improve the attachment and proliferation of Schwann cells in vitro. More importantly, the NGF loaded heparin/chitosan scaffolds could effectively promote the morphology development of Schwann cells. The study may provide a useful experimental basis to design and develop artificial implants for peripheral nerve regeneration and other tissue regeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Chitosan-capped gold nanoparticles for selective and colorimetric sensing of heparin

    International Nuclear Information System (INIS)

    Chen, Zhanguang; Wang, Zhen; Chen, Xi; Xu, Haixiong; Liu, Jinbin

    2013-01-01

    In this contribution, novel chitosan-stabilized gold nanoparticles (AuNPs) were prepared by mixing chitosan with citrate-reductive AuNPs under appropriate conditions. The as-prepared chitosan-stabilized AuNPs were positively charged and highly stably dispersed in aqueous solution. They exhibited weak resonance light scattering (RLS) intensity and a wine red color. In addition, the chitosan-stabilized AuNPs were successfully utilized as novel sensitive probes for the detection of heparin for the first time. It was found that the addition of heparin induced a strong increase of RLS intensity for AuNPs and the color change from red to blue. The increase in RLS intensity and the color change of chitosan-stabilized AuNPs caused by heparin allowed the sensitive detection of heparin in the range of 0.2–60 μM (∼6.7 U/mL). The detection limit for heparin is 0.8 μM at a signal-to-noise ratio of 3. The present sensor for heparin detection possessed a low detection limit and wide linear range. Additionally, the proposed method was also applied to the detection of heparin in biological media with satisfactory results

  7. P-selectin- and heparanase-dependent antimetastatic activity of non-anticoagulant heparins.

    Science.gov (United States)

    Hostettler, Nina; Naggi, Annamaria; Torri, Giangiacomo; Ishai-Michaeli, Riva; Casu, Benito; Vlodavsky, Israel; Borsig, Lubor

    2007-11-01

    Vascular cell adhesion molecules, P- and L-selectins, facilitate metastasis of cancer cells in mice by mediating interactions with platelets, endothelium, and leukocytes. Heparanase is an endoglycosidase that degrades heparan sulfate of extracellular matrix, thereby promoting tumor invasion and metastasis. Heparin is known to efficiently attenuate metastasis in different tumor models. Here we identified modified, nonanticoagulant species of heparin that specifically inhibit selectin-mediated cell-cell interactions, heparanase enzymatic activity, or both. We show that selective inhibition of selectin interactions or heparanase with specific heparin derivatives in mouse models of MC-38 colon carcinoma and B16-BL6 melanoma attenuates metastasis. Selectin-specific heparin derivatives attenuated metastasis of MC-38 carcinoma, but heparanase-specific derivatives had no effect, in accordance with the virtual absence of heparanase activity in these cells. Heparin derivatives had no further effect on metastasis in mice deficient in P- and L-selectin, indicating that selectins are the primary targets of heparin antimetastatic activity. Selectin-specific and heparanase-specific derivatives attenuated metastasis of B16-BL6 melanomas to a similar extent. When mice were injected with a derivative containing both heparanase and selectin inhibitory activity, no additional attenuation of metastasis could be observed. Thus, selectin-specific heparin derivatives efficiently attenuated metastasis of both tumor cell types whereas inhibition of heparanase led to reduction of metastasis only in tumor cells producing heparanase.

  8. Investigation of the heparin-thrombin interaction by dynamic force spectroscopy.

    Science.gov (United States)

    Wang, Congzhou; Jin, Yingzi; Desai, Umesh R; Yadavalli, Vamsi K

    2015-06-01

    The interaction between heparin and thrombin is a vital step in the blood (anti)coagulation process. Unraveling the molecular basis of the interactions is therefore extremely important in understanding the mechanisms of this complex biological process. In this study, we use a combination of an efficient thiolation chemistry of heparin, a self-assembled monolayer-based single molecule platform, and a dynamic force spectroscopy to provide new insights into the heparin-thrombin interaction from an energy viewpoint at the molecular scale. Well-separated single molecules of heparin covalently attached to mixed self-assembled monolayers are demonstrated, whereby interaction forces with thrombin can be measured via atomic force microscopy-based spectroscopy. Further these interactions are studied at different loading rates and salt concentrations to directly obtain kinetic parameters. An increase in the loading rate shows a higher interaction force between the heparin and thrombin, which can be directly linked to the kinetic dissociation rate constant (koff). The stability of the heparin/thrombin complex decreased with increasing NaCl concentration such that the off-rate was found to be driven primarily by non-ionic forces. These results contribute to understanding the role of specific and nonspecific forces that drive heparin-thrombin interactions under applied force or flow conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Characterization of currently marketed heparin products: key tests for LMWH quality assurance.

    Science.gov (United States)

    Ye, Hongping; Toby, Timothy K; Sommers, Cynthia D; Ghasriani, Houman; Trehy, Michael L; Ye, Wei; Kolinski, Richard E; Buhse, Lucinda F; Al-Hakim, Ali; Keire, David A

    2013-11-01

    During the 2007-2008 heparin crisis it was found that the United States Pharmacopeia (USP) testing monograph for heparin sodium or low molecular weight heparins did not detect the presence of the contaminant, oversulfated chondroitin sulfate (OSCS). In response to this concern, new tests and specifications were developed by the Food and Drug Administration (FDA) and USP and put in place to detect not only the contaminant OSCS, but also to improve assurance of quality and purity of these drug products. The USP monographs for the low molecular weight heparins (LMWHs) approved for use in the United States (dalteparin, tinzaparin and enoxaparin) are also undergoing revision to include many of the same tests used for heparin sodium, including; one-dimensional (1D) 500 MHz (1)H NMR, SAX-HPLC, percent galactosamine in total hexosamine and anticoagulation time assays with purified Factor IIa or Factor Xa. These tests represent orthogonal approaches for heparin identification, measurement of bioactivity and for detection of process impurities or contaminants in these drug products. Here we describe results from a survey of multiple lots from three types of LMWHs in the US market which were collected after the 2009 heparin sodium monograph revision. In addition, innovator and generic versions of formulated enoxaparin products purchased in 2011 are compared using these tests and found to be highly similar within the discriminating power of the assays applied. Published by Elsevier B.V.

  10. Chitosan-capped gold nanoparticles for selective and colorimetric sensing of heparin

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhanguang, E-mail: kqlu@stu.edu.cn; Wang, Zhen; Chen, Xi [Shantou University, Department of Chemistry (China); Xu, Haixiong [Shantou Central Hospital, Affiliated Shantou Hospital of SUN YAT-SEN University (China); Liu, Jinbin [University of Texasat Dallas, Department of Chemistry (United States)

    2013-09-15

    In this contribution, novel chitosan-stabilized gold nanoparticles (AuNPs) were prepared by mixing chitosan with citrate-reductive AuNPs under appropriate conditions. The as-prepared chitosan-stabilized AuNPs were positively charged and highly stably dispersed in aqueous solution. They exhibited weak resonance light scattering (RLS) intensity and a wine red color. In addition, the chitosan-stabilized AuNPs were successfully utilized as novel sensitive probes for the detection of heparin for the first time. It was found that the addition of heparin induced a strong increase of RLS intensity for AuNPs and the color change from red to blue. The increase in RLS intensity and the color change of chitosan-stabilized AuNPs caused by heparin allowed the sensitive detection of heparin in the range of 0.2-60 {mu}M ({approx}6.7 U/mL). The detection limit for heparin is 0.8 {mu}M at a signal-to-noise ratio of 3. The present sensor for heparin detection possessed a low detection limit and wide linear range. Additionally, the proposed method was also applied to the detection of heparin in biological media with satisfactory results.

  11. Comparison of established and novel purity tests for the quality control of heparin by means of a set of 177 heparin samples.

    Science.gov (United States)

    Alban, Susanne; Lühn, Susanne; Schiemann, Simone; Beyer, Tanja; Norwig, Jochen; Schilling, Claudia; Rädler, Oliver; Wolf, Bernhard; Matz, Magnus; Baumann, Knut; Holzgrabe, Ulrike

    2011-01-01

    The widespread occurrence of heparin contaminated with oversulfated chrondroitin sulfate (OSCS) in 2008 initiated a comprehensive revision process of the Pharmacopoeial heparin monographs and stimulated research in analytical techniques for the quality control of heparin. Here, a set of 177 heparin samples from the market in 2008 as well as pure heparin sodium spiked with defined amounts of OSCS and DS were used to evaluate established and novel methods for the quality control of heparin. Besides (1)H nuclear magnetic resonance spectroscopy (NMR), the assessment included two further spectroscopic methods, i.e., attenuated total reflection-infrared spectroscopy (ATR-IR) and Raman spectroscopy, three coagulation assays, i.e., activated partial thromboplastin time (aPTT) performed with both sheep and human plasma and the prothrombin time (PT), and finally two novel purity assays, each consisting of an incubation step with heparinase I followed by either a fluorescence measurement (Inc-PolyH-assay) or by a chromogenic aXa-assay (Inc-aXa-assay). NMR was shown to allow not only sensitive detection, but also quantification of OSCS by using the peak-height method and a response factor determined by calibration. Chemometric evaluation of the NMR, ATR-IR, and Raman spectra by statistical classification techniques turned out to be best with NMR spectra concerning the detection of OSCS. The validity of the aPTT, the current EP assay, could be considerably improved by replacing the sheep plasma by human plasma. In this way, most of the contaminated heparin samples did not meet the novel potency limit of 180 IU/mg. However, also more than 50% of the uncontaminated samples had interpretation of the results.

  12. Importance of lipopolysaccharide aggregate disruption for the anti-endotoxic effects of heparin cofactor II peptides.

    Science.gov (United States)

    Singh, Shalini; Papareddy, Praveen; Kalle, Martina; Schmidtchen, Artur; Malmsten, Martin

    2013-11-01

    Lipid membrane and lipopolysaccharide (LPS) interactions were investigated for a series of amphiphilic and cationic peptides derived from human heparin cofactor II (HCII), using dual polarization interferometry, ellipsometry, circular dichroism (CD), cryoTEM, and z-potential measurements. Antimicrobial effects of these peptides were compared to their ability to disorder bacterial lipid membranes, while their capacity to block endotoxic effects of LPS was correlated to the binding of these peptides to LPS and its lipid A moiety, and to charge, secondary structure, and morphology of peptide/LPS complexes. While the peptide KYE28 (KYEITTIHNLFRKLTHRLFRRNFGYTLR) displayed potent antimicrobial and anti-endotoxic effects, its truncated variants KYE21 (KYEITTIHNLFRKLTHRLFRR) and NLF20 (NLFRKLTHRLFRRNFGYTLR) provide some clues on structure-activity relations, since KYE21 retains both the antimicrobial and anti-endotoxic effects of KYE28 (although both attenuated), while NLF20 retains the antimicrobial but only a fraction of the anti-endotoxic effect, hence locating the anti-endotoxic effects of KYE28 to its N-terminus. The antimicrobial effect, on the other hand, is primarily located at the C-terminus of KYE28. While displaying quite different endotoxic effects, these peptides bind to a similar extent to both LPS and lipid A, and also induce comparable LPS scavenging on model eukaryotic membranes. In contrast, fragmentation and densification of LPS aggregates, in turn dependent on the secondary structure in the peptide/LPS aggregates, correlate to the anti-endotoxic effect of these peptides, thus identifying peptide-induced packing transitions in LPS aggregates as key for anti-endotoxic functionality. This aspect therefore needs to be taken into account in the development of novel anti-endotoxic peptide therapeutics. Copyright © 2013. Published by Elsevier B.V.

  13. Community nurse resource implications for a change in heparin prophylaxis policy

    Directory of Open Access Journals (Sweden)

    Parker Martyn J.

    2015-01-01

    Full Text Available Introduction: A review was undertaken for a consecutive series of hip fracture patients for the year before and then after a change in low dose heparin prophylaxis policy. Patients and methods: For the first year heparin was administered in hospital for a maximum of 14 days only. Patients sent home before this time were not discharged taking heparin. For the second year heparin was administered as recommended by NICE guidelines for 28 days from admission regardless of whether the patient was discharged. Results: For the first year 486 patients were treated with a mean of 10.4 doses of heparin per patient. For the second year 465 patients were treated with a mean of 24.3 doses per patient. In total an extra 6,464 doses of heparin were administered. 33.8% of patients were unable to administer their heparin at home therefore a district nurse administered 2,284 of these doses of subcutaneous heparin at the patient’s home. The increased cost associated with the change in policy was estimated to be £161 per patient, with over 90% of this increase being incurred by the district nurse expense. If applied nationally for the England, using extended heparin prophylaxis for hip fracture patients would cost in excess of 12 million pounds each year. Conclusion: Whilst the necessity for and duration of thromboembolic prophylaxis for these patients remains undetermined, there is a need to re-evaluate the cost effectiveness of the current recommendations for hip fracture patients.

  14. Heparin induced thrombocytopenia type ii and myocardial infarction: Two case reports

    Directory of Open Access Journals (Sweden)

    Antonijević Nebojša

    2004-01-01

    Full Text Available Heparin-induced thrombocytopenia (HIT type II is an acquired thrombophylic state and life-threatening immune complication of a heparin treatment mainly clinically manifested by marked thrombocytopenia, frequently by arterial and venous thrombosis, and sometimes by skin changes. Functional assay as heparin aggregation test and 14C-serotonin release assays are used in diagnostics as well as antigen assays of which detection tests for heparin-platelet factor 4 antibodies are most frequently used. Considering the fact that there is no single reliable assays for HIT II detection available, sometimes it is necessary to combine both of the above-mentioned types of assays. We present the case of a 57-year-old patient with an acute anterior myocardial infarction with cardiac insufficiency of III and IV degree according to Killip, recurrent ventricular fibrillation and diabetes mellitus type II developing thrombocytopenia to 37x10 9/l accompanied with typical skin changes. The diagnosis was confirmed by the heparin aggregation test. The second patient aged 70 undergoing the treatment for anteroseptal myocardial infarction and reinfarction of the inferior wall complicated by a cardiogenic shock and acute right bundle branch block developed thrombocytopenia 59x10 9/I on the third day of the heparin therapy, with the remark that he had received a heparin therapy during the first infarction as well. Antibodies against heparin-platelet factor 4 were detected by particle gel ID-HPF4 immunoassay. In both patients, the disease had a lethal outcome despite all then available therapeutic measures applied. Further on we discuss advantages of certain types of tests, a therapy doctrine, need for urgent therapeutic measures, inclusive of the administration of anitithrombins, avoidance of harmful procedures like low-molecular-weight heparins administration and prophylactic platelet transfusion as well as preventive measures.

  15. [Thrombocytopenia induced by type II heparin and myocardial infarct: 2 case reports].

    Science.gov (United States)

    Antonijević, Nabojsa; Stanojević, Milica; Perunicić, Jovan; Djokić, Milan; Miković, Danijla; Kovac, Mirjana; Miljić, Predrag; Milosević, Rajko; Terzić, Branka; Vasiljević, Zorana

    2004-01-01

    Heparin-induced thrombocytopenia (HIT) type II is an acquired thrombophylic state and life-threatening immune complication of a heparin treatment mainly clinically manifested by marked thrombocytopenia, frequently by arterial and venous thrombosis, and sometimes by skin changes. Functional assay as heparin aggregation test and 14C-serotonin release assays are used in diagnostics as well as antigen assays of which detection tests for heparin-platelet factor 4 antibodies are most frequently used. Considering the fact that there is no single reliable assays for HIT II detection available, sometimes it is necessary to combine both of the above-mentioned types of assays. We present the case of a 57-year-old patient with an acute anterior myocardial infarction with cardiac insufficiency of III and IV degree according to Killip, recurrent ventricular fibrillation and diabetes mellitus type II developing thrombocytopenia to 37 x 10(9)/l accompanied with typical skin changes. The diagnosis was confirmed by the heparin aggregation test. The second patient aged 70 undergoing the treatment for anteroseptal myocardial infarction and reinfarction of the inferior wall complicated by a cardiogenic shock and acute right bundle branch block developed thrombocytopenia 59 x 10(9)/l on the third day of the heparin therapy, with the remark that he had received a heparin therapy during the first infarction as well. Antibodies against heparin-platelet factor 4 were detected by particle gel ID-HPF4 immuno-assay. In both patients, the disease had a lethal outcome despite all then available therapeutic measures applied. Further on we discuss advantages of certain types of tests, a therapy doctrine, need for urgent therapeutic measures, inclusive of the administration of antithrombins, avoidance of harmful procedures like low-molecular-weight heparins administration and prophylactic platelet transfusion as well as preventive measures.

  16. Heparan sulfate C5-epimerase is essential for heparin biosynthesis in mast cells.

    Science.gov (United States)

    Feyerabend, Thorsten B; Li, Jin-Ping; Lindahl, Ulf; Rodewald, Hans-Reimer

    2006-04-01

    Biosynthesis of heparin, a mast cell-derived glycosaminoglycan with widespread importance in medicine, has not been fully elucidated. In biosynthesis of heparan sulfate (HS), a structurally related polysaccharide, HS glucuronyl C5-epimerase (Hsepi) converts D-glucuronic acid (GlcA) to L-iduronic acid (IdoA) residues. We have generated Hsepi-null mouse mutant mast cells, and we show that the same enzyme catalyzes the generation of IdoA in heparin and that 'heparin' lacking IdoA shows a distorted O-sulfation pattern.

  17. Increased accuracy in heparin and protamine administration decreases bleeding: a pilot study

    DEFF Research Database (Denmark)

    Runge, Marx; Møller, Christian H; Steinbrüchel, Daniel A

    2009-01-01

    Three to 5 percent of the patients undergoing cardiac surgery are reoperated because of bleeding. When a surgical cause can be excluded, heparin/protamine mismatch may be considered. Insufficient reversal of heparin and overdosing of protamine may cause postoperative bleeding. The purpose......). A reduced number of patients needed blood transfusions in the RxDx group, although this was not statistically significant (19% vs. 38%, respectively; p = .13). Initial heparin dose was significantly reduced in the RxDx group (250 mg; range, 100-375 mg) compared with the control group (300 mg; range, 200...

  18. Recent developments in separation of low molecular weight heparin anticoagulants.

    Science.gov (United States)

    Sadowski, Radosław; Gadzała-Kopciuch, Renata; Buszewski, Bogusław

    2017-10-05

    The general function of anticoagulants is to prevent blood clotting and growing of the existing clots in blood vessels. In recent years, there has been a significant improvement in developing methods of prevention as well as pharmacologic and surgical treatment of thrombosis. For over the last two decades, low molecular weight heparins (LMWHs) have found their application in the antithrombotic diseases treatment. These types of drugs are widely used in clinical therapy. Despite the biological and medical importance of LMWHs, they have not been completely characterized in terms of their chemical structure. Due to both, the structural complexity of these anticoagulants and the presence of impurities, their structural characterization requires the employment of advanced analytical techniques. Since separation techniques play the key role in these endeavors, this review will focus on the presentation of recent developments in the separation of LMWH anticoagulants. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. Hyaluronan- and heparin-reduced silver nanoparticles with antimicrobial properties

    Science.gov (United States)

    Kemp, Melissa M; Kumar, Ashavani; Clement, Dylan; Ajayan, Pulickel; Mousa, Shaker

    2009-01-01

    Aims Silver nanoparticles exhibit unique antibacterial properties that make these ideal candidates for biological and medical applications. We utilized a clean method involving a single synthetic step to prepare silver nanoparticles that exhibit antimicrobial activity. Materials & methods These nanoparticles were prepared by reducing silver nitrate with diaminopyridinylated heparin (DAPHP) and hyaluronan (HA) polysaccharides and tested for their efficacy in inhibiting microbial growth. Results & discussion The resulting silver nanoparticles exhibit potent antimicrobial activity against Staphylococcus aureus and modest activity against Escherichia coli. Silver–HA showed greater antimicrobial activity than silver–DAPHP, while silver–glucose nanoparticles exhibited very weak antimicrobial activity. Neither HA nor DAPHP showed activity against S. aureus or E. coli. Conclusion These results suggest that DAPHP and HA silver nanoparticles have potential in antimicrobial therapeutic applications. PMID:19505245

  20. Role of Heparan Sulfate in Cellular Infection of Integrin-Binding Coxsackievirus A9 and Human Parechovirus 1 Isolates.

    Directory of Open Access Journals (Sweden)

    Pirjo Merilahti

    Full Text Available Heparan sulfate/heparin class of proteoglycans (HSPG have been shown to function in cellular attachment and infection of numerous viruses including picornaviruses. Coxsackievirus A9 (CV-A9 and human parechovirus 1 (HPeV-1 are integrin-binding members in the family Picornaviridae. CV-A9 Griggs and HPeV-1 Harris (prototype strains have been reported not to bind to heparin, but it was recently shown that some CV-A9 isolates interact with heparin in vitro via VP1 protein with a specific T132R/K mutation. We found that the infectivity of both CV-A9 Griggs and HPeV-1 Harris was reduced by sodium chlorate and heparinase suggestive of HSPG interactions. We analyzed the T132 site in fifty-four (54 CV-A9 clinical isolates and found that only one of them possessed T132/R mutation while the other nine (9 had T132K. We then treated CV-A9 Griggs and HPeV-1 Harris and eight CV-A9 and six HPeV-1 clinical isolates with heparin and protamine. Although infectivity of Griggs strain was slightly reduced (by 25%, heparin treatment did not affect the infectivity of the CV-A9 isolates that do not possess the T132R/K mutation, which is in line with the previous findings. Some of the HPeV-1 isolates were also affected by heparin treatment, which suggested that there may be a specific heparin binding site in HPeV-1. In contrast, protamine (a specific inhibitor of heparin completely inhibited the infection of both prototypes and clinical CV-A9 and HPeV-1 isolates. We conclude that T132R/K mutation has a role in heparin binding of CV-A9, but we also show data, which suggest that there are other HSPG binding sites in CV-A9. In all, we suggest that HSPGs play a general role in both CV-A9 and HPeV-1 infections.

  1. Obstetric outcome with low molecular weight heparin therapy during pregnancy.

    LENUS (Irish Health Repository)

    Donnelly, J

    2012-01-01

    This was a prospective study of women attending a combined haematology\\/obstetric antenatal clinic in the National Maternity Hospital (2002-2008). Obstetric outcome in mothers treated with low molecular weight heparin (LMWH) was compared to the general obstetric population of 2006. There were 133 pregnancies in 105 women. 85 (63.9%) received prophylactic LMWH and 38 (28.6%) received therapeutic LMWH in pregnancy. 10 (7.5%) received postpartum prophylaxis only. The perinatal mortality rate was 7.6\\/1000 births. 14 (11.3%) women delivered preterm which is significantly higher than the hospital population rate (5.7%, p<0.05). Despite significantly higher labour induction rates (50% vs 29.2% p<0.01), there was no difference in CS rates compared to the general hospital population (15.4% vs 18.9%, NS). If carefully managed, these high-risk women can achieve similar vaginal delivery rates as the general obstetric population.

  2. Qualitative and quantitative analysis of heparin and low molecular weight heparins using size exclusion chromatography with multiple angle laser scattering/refractive index and inductively coupled plasma/mass spectrometry detectors.

    Science.gov (United States)

    Ouyang, Yilan; Zeng, Yangyang; Yi, Lin; Tang, Hong; Li, Duxin; Linhardt, Robert J; Zhang, Zhenqing

    2017-11-03

    Heparin, a highly sulfated glycosaminoglycan, has been used as a clinical anticoagulant over 80 years. Low molecular weight heparins (LMWHs), heparins partially depolymerized using different processes, are widely used as clinical anticoagulants. Qualitative molecular weight (MW) and quantitative mass content analysis are two important factors that contribute to LMWH quality control. Size exclusion chromatography (SEC), relying on multiple angle laser scattering (MALS)/refractive index (RI) detectors, has been developed for accurate analysis of heparin MW in the absence of standards. However, the cations, which ion-pair with the anionic polysaccharide chains of heparin and LMWHs, had not been considered in previous reports. In this study, SEC with MALS/RI and inductively coupled plasma/mass spectrometry detectors were used in a comprehensive analytical approach taking both anionic polysaccharide and ion-paired cations heparin products. This approach was also applied to quantitative analysis of heparin and LMWHs. Full profiles of MWs and mass recoveries for three commercial heparin/LMWH products, heparin sodium, enoxaparin sodium and nadroparin calcium, were obtained and all showed higher MWs than previously reported. This important improvement more precisely characterized the MW properties of heparin/LMWHs and potentially many other anionic polysaccharides. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Reptured Epidermal Inclusion Cyst in the Axilla: A Case Report

    International Nuclear Information System (INIS)

    Kim, Kyu Soon; Kim, Hak Hee; Shin, Hee Jeong; Yang, Hye Rin; Sohn, Jeong Hee; Kwon, Gui Young; Gong, Gyung Yub

    2006-01-01

    Epidermal inclusion cysts, the most common type of simple epithelial cyst, are typically well-encapsulated, subepidermal and mobile nodules. They may occur anywhere, but are mostly found on the scalp, face, neck, trunk, and back. Less than 10% of epidermal inclusion cysts occur on the extremities, and even fewer are found on the palms, soles, and breasts. If epidermal inclusion cysts rupture, foreign body reaction, granulomatous reaction or abscess formation could follow. We described here the sonographic findings of ruptured epidermal inclusion cyst of the right axilla in a 33-year-old woman who presented with a palpable axillary mass forming an inflammatory abscess

  4. Preparation of tin -heparin complex to be applied for myocardial infarct diagnosis

    International Nuclear Information System (INIS)

    Badi, J. M.; Al-Azzawi, H. A.; Resen, H. M.; Abed, I. G.; Owiad, H.; Manji, A. N.

    2012-12-01

    Tin-heparin complex has been prepared (liquid form) to be labeled with technetium-99 can be applied for diagnosis of myocardial infarcts vascular diseases and deep vein thrombosis. The preparation contents are 0.1mg tin chloride dehydrate and 1250 1.U of heparin. The results of the pH effect on the labeling yield indicated that high percentage of labeling yield (96.1%) was obtained in the optimal pH (5.50). The obtained results showed that the quantity of reducing agent (tin chloride dehydrate) and chelating agent (heparin) has no effect on the labeling yield. Results of radio analytical studies by paper chromatography technique wear confirmed by data obtained by Gel chromatography column scanning techniques. These techniques showed the high labeling yield of the tin-heparin complex. The persistence of high labeling yield for 8 hours is a good indication for its stability and efficiency for radio diagnosis examination in nuclear medicine centers. (Author)

  5. Distribution of heparin-/sup 67/Ga in tumor-bearing rats

    Energy Technology Data Exchange (ETDEWEB)

    Hiraki, T; Ando, A; Sanada, S [Kanazawa Univ. (Japan). School of Paramedicine; Ando, I; Hisada, K

    1976-06-01

    Heparin is a kind of acidic mucopolysaccharide. The distribution of heparin-/sup 67/Ga complex in tumor-bearing rats was investigated by administering it to rats into which Yoshida sarcoma had been transplanted subcutaneously. These rats were sacrificed at 10 minutes, 30 minutes, 1 hour and 3 hours after injection. Radioactivity of the tumor, blood, muscle, liver, kidney, spleen and urine were measured with a well-type scintillation counter. Retention values in these organs and excretion rates in the urine were calculated. Excretion rates (%/dose) of heparin-/sup 67/Ga in 10 min., 30 min., 1 hour, and 3 hours were 38.2%, 67.5%, 79.5% and 78.0%, respectively. From these facts, it was thought that heparin-/sup 67/Ga complex was not suitable for tumor scanning, but that this compound might be a suitable agent for the renal function test.

  6. Bilateral adrenal haemorrhage associated with heparin-induced thrombocytopaenia during treatment of Fournier gangrene.

    Science.gov (United States)

    Tattersall, Timothy Lee; Thangasamy, Isaac A; Reynolds, Jamie

    2014-10-14

    We present a case of bilateral adrenal haemorrhage (BAH) associated with heparin-induced thrombocytopaenia (HIT) in a 61-year-old man admitted to hospital for the treatment of Fournier's gangrene. He presented to hospital with scrotal swelling and fever, and developed spreading erythaema and a gangrenous scrotum. His scrotum was surgically debrided and intravenous broad-spectrum antibiotics were administered. Unfractionated heparin was given postoperatively for venous thromboembolism prophylaxis. The patient deteriorated clinically 8-11 days postoperatively with delirium, chest pain and severe hypertension followed by hypotension and thrombocytopaenia. Abdominal CT scan revealed bilateral adrenal haemorrhage. Antibodies to the heparin-platelet factor 4 complex were present. HIT-associated BAH was diagnosed and heparin was discontinued. Intravenous bivalirudin and hydrocortisone were started, with rapid improvement in clinical status. BAH is a rare complication of HIT and should be considered in the postoperative patient with unexplained clinical deterioration. 2014 BMJ Publishing Group Ltd.

  7. Culture technique of rabbit primary epidermal keratinocytes

    Directory of Open Access Journals (Sweden)

    Marini M

    2012-10-01

    Full Text Available The epidermis is the protective covering outer layer of the mammalian skin. The epidermal cells are stratified squamous epithelia which undergo continuous differentiation of loss and replacement of cells. Ninety per cent of epidermal cells consist of keratinocytes that are found in the basal layer of the stratified epithelium called epidermis. Keratinocytes are responsible for forming tight junctions with the nerves of the skin as well as in the process of wound healing. This article highlights the method of isolation and culture of rabbit primary epidermal keratinocytes in vitro. Approximately 2cm x 2cm oval shaped line was drawn on the dorsum of the rabbit to mark the surgical area. Then, the skin was carefully excised using a surgical blade and the target skin specimens harvested from the rabbits were placed in transport medium comprising of Dulbecco’s Modified Eagle Medium (DMEM and 1% of antibiotic-antimycotic solution. The specimens were transferred into a petri dish containing 70% ethanol and washed for 5 min followed by a wash in 1 x Dulbecco’s Phosphate Buffered Saline (DBPS. Then, the skin specimens were placed in DMEM and minced into small pieces using a scalpel. The minced pieces were placed in a centrifuge tube containing 0.6% Dispase and 1% antibiotic-antimycotic solution overnight at 4°C in a horizontal orientation. The epidermis layer (whitish, semi-transparent was separated from the dermis (pink, opaque, gooey with the aid of curved forceps by fixing the dermis with one pair of forceps while detaching the epidermis with the second pair. The cells were cultured at a density of 4 x 104 cells/cm2 in culture flask at 37°C and 5% CO2. The cell morphology of the keratinocytes was analyzed using inverted microscope.

  8. Indium-111-labeled platelets: effect of heparin on uptake by venous thrombi and relationship to the activated partial thromboplastin time

    International Nuclear Information System (INIS)

    Fedullo, P.F.; Moser, K.M.; Moser, K.S.; Konopka, R.; Hartman, M.T.

    1982-01-01

    The goal of heparin thepapy in deep vein thrombosis is to prevent thrombus extension. The relationship between thrombus extension and the results of coagulation tests used to monitor heparin thepapy is unclear. To expose this relationship, we studied the effect of several heparin regimens on the accretion of indium-111-labeled platelets on fresh venous thrombi, as detected by gamma imaging, and monitored the activated partial thromboplastin time (APTT). Six dogs were treated with a 300-U/kg bolus of heparin followed by a 90-U/kg/hour heparin infusion, a dose of heparin sufficient to increase the APTT to levels greater than eight times baseline (APTT ratio); platelet accretion (thrombus imaging) occurred only after the heparin effect was reversed with protamine sulfate. Nineteen dogs were treated with a 150-U/kg bolus of heparin followed by a 4-hour, 45-U/kg/hour heparin infusion; a thrombus was demonstrated only after protamine injection in 12 (mean APTT ratio 1.3 +/- 0.19) and before protamine injection in seven. In thirteen of these 19 dogs, 30 minutes separated the platelet injection from heparin therapy, while in six this duration was less than 30 minutes. In four of these six dogs, thrombi were demonstrated before protamine therapy and at APTT ratios greater than 3.0. Finally, 10 dogs were treated with a 100-U/kg bolus followed by a 3-hour, 50-U/kg/hour heparin infusion, after which the APTT was allowed to return to baseline values spontaneously. In all 10 dogs, a thrombus was demonstrated only after cessation of the heparin infusion, and at a mean APTT ratio of 1.4 +/- 0.15 times baseline. These results suggest that, except with very early platelet injection, platelet accretion by thrombi is consistently inhibited by heparin at APTT ratios greater than 2.5

  9. Ultrasensitive colorimetric detection of heparin based on self-assembly of gold nanoparticles on graphene oxide.

    Science.gov (United States)

    Fu, Xiuli; Chen, Lingxin; Li, Jinhua

    2012-08-21

    A novel colorimetric method was developed for ultrasensitive detection of heparin based on self-assembly of gold nanoparticles (AuNPs) onto the surface of graphene oxide (GO). Polycationic protamine was used as a medium for inducing the self-assembly of citrate-capped AuNPs on GO through electrostatic interaction, resulting in a shift in the surface plasmon resonance (SPR) absorption of AuNPs and exhibiting a blue color. Addition of polyanionic heparin disturbed the self-assemble of AuNPs due to its strong affinity to protamine. With the increase of heparin concentration, the amounts of self-assembly AuNPs decreased and the color changed from blue to red in solution. Therefore, a "blue-to-red" colorimetric sensing strategy based on self-assembly of AuNPs could be established for heparin detection. Compared with the commonly reported aggregation-based methods ("red-to-blue"), the color change from blue to red was more eye-sensitive, especially in low concentration of target. Moreover, stronger interaction between protamine and heparin led to distinguish heparin from its analogues as well as various potentially coexistent physiological species. The strategy was simply achieved by the self-assembly nature of AuNPs and the application of two types of polyionic media, showing it to be label-free, simple, rapid and visual. This method could selectively detect heparin with a detection limit of 3.0 ng mL(-1) in standard aqueous solution and good linearity was obtained over the range 0.06-0.36 μg mL(-1) (R = 0.9936). It was successfully applied to determination of heparin in fetal bovine serum samples as low as 1.7 ng mL(-1) with a linear range of 0-0.8 μg mL(-1).

  10. Biomimetic synthesis and biocompatibility evaluation of carbonated apatites template-mediated by heparin

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Yi [Department of Oral and Maxillofacial Surgery, Laboratory of Interdisciplinary Studies, School and Hospital of Stomatology, Peking University, Beijing 100081 (China); Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Sun, Yuhua [Department of Oral and Maxillofacial Surgery, Laboratory of Interdisciplinary Studies, School and Hospital of Stomatology, Peking University, Beijing 100081 (China); Chen, Xiaofang [Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Zhu, Peizhi, E-mail: pzzhu@umich.edu [Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China); Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Wei, Shicheng, E-mail: sc-wei@pku.edu.cn [Department of Oral and Maxillofacial Surgery, Laboratory of Interdisciplinary Studies, School and Hospital of Stomatology, Peking University, Beijing 100081 (China); Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871 (China)

    2013-07-01

    Biomimetic synthesis of carbonated apatites with good biocompatibility is a promising strategy for the broadening application of apatites for bone tissue engineering. Most researchers were interested in collagen or gelatin-based templates for synthesis of apatite minerals. Inspired by recent findings about the important role of polysaccharides in bone biomineralization, here we reported that heparin, a mucopolysaccharide, was used to synthesize carbonated apatites in vitro. The results indicated that the Ca/P ratio, carbon content, crystallinity and morphology of the apatites varied depending on the heparin concentration and the initial pH value. The morphology of apatite changed from flake-shaped to needle-shaped, and the degree of crystallinity decreased with the increasing of heparin concentration. Biocompatibility of the apatites was tested by proliferation and alkaline phosphatase activity of MC3T3-E1 cells. The results suggested that carbonated apatites synthesized in the presence of heparin were more favorable to the proliferation and differentiation of MC3T3-E1 cells compared with traditional method. In summary, the heparin concentration and the initial pH value play a key role in the chemical constitution and morphology, as well as biological properties of apatites. These biocompatible nano-apatite crystals hold great potential to be applied as bioactive materials for bone tissue engineering. - Highlights: • Heparin was used as a template to synthesize needle-shaped nano-apatite. • Changing the pH value and concentration led to different properties of apatite. • Apatite prepared by heparin was more favorable to the osteogenic differentiation. • Possible synthesis mechanism of apatite templated by heparin was described.

  11. Elimination of heparin interference during microarray processing of fresh and biobank-archived blood samples.

    Science.gov (United States)

    Hebels, Dennie G A J; van Herwijnen, Marcel H M; Brauers, Karen J J; de Kok, Theo M C M; Chalkiadaki, Georgia; Kyrtopoulos, Soterios A; Kleinjans, Jos C S

    2014-07-01

    In the context of environmental health research, biobank blood samples have recently been identified as suitable for high-throughput omics analyses enabling the identification of new biomarkers of exposure and disease. However, blood samples containing the anti-coagulant heparin could complicate transcriptomic analysis because heparin may inhibit RNA polymerase causing inefficient cRNA synthesis and fluorophore labelling. We investigated the inhibitory effect of heparin and the influence of storage conditions (0 or 3 hr bench times, storage at room temperature or -80°C) on fluorophore labelling in heparinized fresh human buffy coat and whole blood biobank samples during the mRNA work-up protocol for microarray analysis. Subsequently, we removed heparin by lithium chloride (LiCl) treatment and performed a quality control analysis of LiCl-treated biobank sample microarrays to prove their suitability for downstream data analysis. Both fresh and biobank samples experienced varying degrees of heparin-induced inhibition of fluorophore labelling, making most samples unusable for microarray analysis. RNA derived from EDTA and citrate blood was not inhibited. No effect of bench time was observed but room temperature storage gave slightly better results. Strong correlations were observed between original blood sample RNA yield and the amount of synthesized cRNA. LiCl treatment restored sample quality to normal standards in both fresh and biobank samples and the previously identified correlations disappeared. Microarrays hybridized with LiCl-treated biobank samples were of excellent quality with no identifiable influence of heparin. We conclude that, to obtain high quality results, in most cases heparin removal is essential in blood-derived RNA samples intended for microarray analysis. Copyright © 2014 Wiley Periodicals, Inc.

  12. Prospective multicentre cohort study of heparin-induced thrombocytopenia in acute ischaemic stroke patients

    Science.gov (United States)

    Kawano, Hiroyuki; Yamamoto, Haruko; Miyata, Shigeki; Izumi, Manabu; Hirano, Teruyuki; Toratani, Naomi; Kakutani, Isami; Sheppard, Jo-Ann I; Warkentin, Theodore E; Kada, Akiko; Sato, Shoichiro; Okamoto, Sadahisa; Nagatsuka, Kazuyuki; Naritomi, Hiroaki; Toyoda, Kazunori; Uchino, Makoto; Minematsu, Kazuo

    2011-01-01

    Acute ischaemic stroke patients sometimes receive heparin for treatment and/or prophylaxis of thromboembolic complications. This study was designed to elucidate the incidence and clinical features of heparin-induced thrombocytopenia (HIT) in acute stroke patients treated with heparin. We conducted a prospective multicentre cohort study of 267 patients who were admitted to three stroke centres within 7 d after stroke onset. We examined clinical data until discharge and collected blood samples on days 1 and 14 of hospitalization to test anti-platelet factor 4/heparin antibodies (anti-PF4/H Abs) using an enzyme-linked immunosorbent assay (ELISA); platelet-activating antibodies were identified by serotonin-release assay (SRA). Patients with a 4Ts score ≥4 points, positive-ELISA, and positive-SRA were diagnosed as definite HIT. Heparin was administered to 172 patients (64·4%: heparin group). Anti-PF4/H Abs were detected by ELISA in 22 cases (12·8%) in the heparin group. Seven patients had 4Ts ≥ 4 points. Among them, three patients (1·7% overall) were also positive by both ELISA and SRA. National Institutes of Health Stroke Scale score on admission was high (range, 16–23) and in-hospital mortality was very high (66·7%) in definite HIT patients. In this study, the incidence of definite HIT in acute ischaemic stroke patients treated with heparin was 1·7% (95% confidence interval: 0·4–5·0). The clinical severity and outcome of definite HIT were unfavourable. PMID:21671895

  13. Anticoagulation and endothelial cell behaviors of heparin-loaded graphene oxide coating on titanium surface

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Chang-Jiang, E-mail: panchangjiang@hyit.edu.cn [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai' an 223003 (China); Pang, Li-Qun [Department of General Surgery, Huai' an First People' s Hospital, Nanjing Medical University, Huai' an 223300 (China); Gao, Fei [Zhejiang Zylox Medical Devices Co., Ltd., Hangzhou 310000 (China); Wang, Ya-Nan; Liu, Tao; Ye, Wei; Hou, Yan-Hua [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huai' an 223003 (China)

    2016-06-01

    Owing to its unique physical and chemical properties, graphene oxide (GO) has attracted tremendous interest in many fields including biomaterials and biomedicine. The purpose of the present study is to investigate the endothelial cell behaviors and anticoagulation of heparin-loaded GO coating on the titanium surface. To this end, the titanium surface was firstly covered by the polydopamine coating followed by the deposition of the GO coating. Heparin was finally loaded on the GO coating to improve the blood compatibility. The results of attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) indicated that the heparin-loaded GO coating was successfully created on the titanium surface. The scanning electron microscopy (SEM) images indicated that a relative uniform GO coating consisting of multilayer GO sheets was formed on the substrate. The hydrophilicity of the titanium surface was enhanced after the deposition of GO and further improved significantly by the loading heparin. The GO coating can enhance the endothelial cell adhesion and proliferation as compared with polydopamine coating and the blank titanium. Loading heparin on the GO coating can significantly reduce the platelet adhesion and prolong the activated partial thromboplastin time (APTT) while not influence the endothelial cell adhesion and proliferation. Therefore, the heparin-loaded GO coating can simultaneously enhance the cytocompatibility to endothelial cells and blood compatibility of biomaterials. Because the polydopamine coating can be easily prepared on most of biomaterials including polymer, ceramics and metal, thus the approach of the present study may open up a new window of promising an effective and efficient way to promote endothelialization and improve the blood compatibility of blood-contact biomedical devices such as intravascular stents. - Highlights: • Heparin-loaded graphene oxide coating was

  14. The Epidermal Growth Factor Receptor Is a Regulator of Epidermal Complement Component Expression and Complement Activation

    DEFF Research Database (Denmark)

    Abu-Humaidan, Anas H A; Ananthoju, Nageshwar; Mohanty, Tirthankar

    2014-01-01

    The complement system is activated in response to tissue injury. During wound healing, complement activation seems beneficial in acute wounds but may be detrimental in chronic wounds. We found that the epidermal expression of many complement components was only increased to a minor extent in skin...

  15. Eps15 is recruited to the plasma membrane upon epidermal growth factor receptor activation and localizes to components of the endocytic pathway during receptor internalization

    DEFF Research Database (Denmark)

    Torrisi, M R; Lotti, L V; Belleudi, F

    1999-01-01

    Eps15 is a substrate for the tyrosine kinase of the epidermal growth factor receptor (EGFR) and is characterized by the presence of a novel protein:protein interaction domain, the EH domain. Eps15 also stably binds the clathrin adaptor protein complex AP-2. Previous work demonstrated an essential...

  16. The development of epidermal growth factor receptor molecular imaging in cancer

    International Nuclear Information System (INIS)

    Zhou Xiaoliang; Wang Hao; Shi Peiji; Liu Jianfeng; Meng Aimin

    2013-01-01

    In vivo epidermal growth factor receptor (EGFR) targeted therapy has great potential for cancer diagnosis and the evaluation of curative effects. Enhancement of EGFR-targeted therapy needs a reliable quantitative molecular imaging method which could enable monitoring of receptor drug binding and receptor occupancy in vivo, and identification of the mutation in EGFR. PET or SPECT is the most advanced molecular imaging technology of non-invasively selecting responders, predicting therapeutic outcome and monitoring EGFR-targeted treatment. This review analyzed the present situation and research progress of molecular imaging agents. (authors)

  17. Roles of p63 in epidermal development and tumorigenesis

    Directory of Open Access Journals (Sweden)

    Jeng-Yuan Yao

    2012-12-01

    Full Text Available pidermis is composed mainly of keratinocytes and is the ma­jor barrier of human body. The development and maintenance of normal epithelial structures and functions require the transcrip­tion factor p63. The p63 gene encodes proteins with structures simi­lar to that of p53, including an N-terminal transacti­vation (TA domain, a DNA-binding domain and a car­boxy-oligomerization domain. TAp63 and ΔNp63 (p63 isoforms without TA domain regulate a wide range of target genes that are important for embryonal development and epithelial integrity. Mutations of p63 gene cause epider­mal abnormalities characterized by ectodermal dysplasia. Recent reports have indicated that p63 plays important role in tumorigenesis as well. However, the relative importance of TAp63 and ΔNp63 in epidermal development and tumorigenesis re­mains mostly unclear and awaits further investigation. In this review, we summarize the current knowledge on the structure and function of p63 and its isoforms.

  18. Update on the clinical use of the low-molecular-weight heparin, parnaparin

    Directory of Open Access Journals (Sweden)

    Giuseppe Camporese

    2009-09-01

    Full Text Available Giuseppe Camporese1, Enrico Bernardi2, Franco Noventa31Unit of Angiology and 3Department of Clinical and Experimental Medicine, Clinical Epidemiology Group, University Hospital of Padua, Italy; 2Department of Emergency and Accident Medicine, Hospital of Conegliano Veneto, ItalyAbstract: Parnaparin is a low-molecular-weight heparin that has widely shown its efficacy and safety in prevention of venous thromboembolism, in the treatment of chronic venous disorders, and in the treatment of venous and arterial (stable and unstable angina, acute ST-segment elevation myocardial infarction thrombosis. Parnaparin at the respective dosages of 3200, 4250, 6400, or 12800 IUaXa for a period ranging from 3 to 5 days to 6 months, is usually administered subcutaneously by means of once-daily regimen and is better tolerated than unfractionated heparin at the injection site. In the variety of commercially available low-molecular-weight heparins, parnaparin represents a useful therapeutic option, even though little evidence is available comparing the superiority or the equivalent efficacy and safety of parnaparin to that of the unfractionated heparin or placebo. This review summarizes the available literature on the use of parnaparin in different settings of cardiovascular diseases, including papers published during the past year and ongoing studies.Keywords: low-molecular-weight heparin, heparin, parnaparin, acute coronary syndromes, venous thromboembolism

  19. Preparation and in vitro evaluation of heparin-loaded polymeric nanoparticles.

    Science.gov (United States)

    Jiao, Y Y; Ubrich, N; Marchand-Arvier, M; Vigneron, C; Hoffman, M; Maincent, P

    2001-01-01

    Nanoparticles of a highly soluble macromolecular drug, heparin, were formulated with two biodegradable polymers (poly-E-caprolactone [PCL] and poly (D, L-lactic-co-glycolic-acid) 50/50 [PLAGA]) and two nonbiodegradable positively charged polymers (Eudragit RS and RL) by the double emulsion and solvent evaporation method, using a high-pressure homogenization device. The encapsulation efficiency and heparin release profiles were studied as a function of the type of polymers employed (alone or in combination) and the concentration of heparin. Optimal encapsulation efficiency was observed when 5000 IU of heparin were incorporated in the first emulsion. High drug entrapment efficiency was observed in both Eudragit RS and RL nanoparticles (60% and 98%, respectively), compared with PLAGA and PCL nanoparticles (PLAGA increased the encapsulation efficiency compared with these two biodegradable polymers used alone; however, the in vitro drug release was not modified and remained low. On the other hand, the addition of esterase to the dissolution medium resulted in a significant increase in heparin release. The in vitro biological activity of released heparin, evaluated by measuring the anti-Xa activity by a colorimetric assay, was conserved after the encapsulation process.

  20. [Heparin-induced thrombocytopenia developed during the acute phase after left upper lobectomy for lung cancer].

    Science.gov (United States)

    Mitomo, Hideki; Miyamoto, Akira; Tabata, Toshiharu; Sugawara, Takafumi; Yabuki, Hiroshi; Fujimura, Shigefumi

    2014-12-01

    Heparin-induced thrombocytopenia (HIT) is a serious adverse effect of heparin administration. This must not be rarely encountered but is not often reported in Japan compared to Western countries. A 68-year-old woman underwent left upper lobectomy for lung cancer. Low-dose unfractionated heparin was administrated to prevent thromboembolism after the operation. Two days later, sudden dyspnea appeared and ultracardiosonography showing an extensive thromboembolus from the main trunk to both main branches of pulmonary artery indicated pulmonary embolization. After the establishment of percutaneous cardiopulmonary support (PCPS) support, the embolus was removed by emergent open heart surgery. However, despite further unfractionated heparin administration following embolization surgery, other thrombus was identified in both the bi-lateral internal jagular veins and inferior vena cava by ultrasonography and contrast computed tomography( CT). Her platelet count was decreased gradually despite platelet transfusion. Plate factor 4( PF4) antibody against heparin in her blood examination was found, and HIT II was diagnosed. Discontinuation of unfractionated heparin and administration of antithrombin agent improved platelet count, and no additional embolization was identified.

  1. Prevention of equine herpesvirus myeloencephalopathy - Is heparin a novel option? A case report.

    Science.gov (United States)

    Walter, Jasmin; Seeh, Christoph; Fey, Kerstin; Bleul, Ulrich; Osterrieder, Nikolaus

    2016-10-12

    Equine herpesvirus myeloencephalopathy (EHM) is a severe manifestation of equine herpesvirus 1 (EHV-1) infection. Prevention and treatment of EHM during EHV-1 outbreaks is critical, but no reliable and tested specific medication is available. Due to the thromboischemic nature of EHM and due to the fact that EHV-1 entry in cells is blocked by heparin, it was hypothesized that this compound may be useful in reduction of EHM incidence and severity. Therefore, during an acute EHV-1 outbreak with the neuropathogenic G 2254 /D 752 Pol variant, metaphylactic treatment with heparin to prevent EHM was initiated. Clinical signs were present in 61 horses (fever n = 55; EHM n = 8; abortion n = 6). Heparin (25000 IU subcutaneously twice daily for 3 days) was given to 31 febrile horses from day 10 of the outbreak, while the first 30 horses exhibiting fever remained untreated. Treatment outcome was analyzed retrospectively. Heparin-treated horses showed a lower EHM incidence (1/31; 3.2%) than untreated horses (7/30; 23.3%; p = 0.03). Results indicate that heparin may be useful for prevention of EHM during an EHV-1 outbreak. These promising data highlight the need for randomized and possibly blinded studies for the use of heparin in EHV-1 outbreaks.

  2. Heparin concentration is critical for cell culture with human platelet lysate.

    Science.gov (United States)

    Hemeda, Hatim; Kalz, Jana; Walenda, Gudrun; Lohmann, Michael; Wagner, Wolfgang

    2013-09-01

    Culture media for mesenchymal stromal cells (MSCs) are generally supplemented with fetal bovine serum. Human platelet lysate (hPL) has been proven to be a very effective alternative without the risk of xenogeneic infections or immune reactions. In contrast to fetal bovine serum, hPL comprises plasma, and anticoagulants-usually unfractionated heparin (UFH)-need to be added to prevent gel formation. Cultures of MSCs in hPL media with various concentrations of UFH and enoxaparin, a low-molecular-weight heparin (LMWH), were systematically compared with regard to proliferation, fibroblastoid colony-forming unit frequency, immunophenotype and in vitro differentiation. At least 0.61 IU/mL UFH or 0.024 mg/mL LMWH was necessary for reliable prevention of coagulation of hPL pools used in this study. Higher concentrations impaired cellular proliferation in a dose-dependent manner even without benzyl alcohol, which is commonly added to heparins as a bacteriostatic agent. Colony-forming unit frequency was also reduced at higher heparin concentrations, particularly with LMWH, whereas no significant effect was observed on cellular morphology or immunophenotype. High concentrations of heparins reduced the in vitro differentiation toward adipogenic and osteogenic lineages. Heparin concentration is critical for culture of MSCs in hPL media; this is of particular relevance for cellular therapy where cell culture procedures need to be optimized and standardized. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  3. Association between Activated Partial Thromboplastin Time and the Amount of Infused Heparin at Bone Marrow Transplantation.

    Science.gov (United States)

    Kusuda, Machiko; Kimura, Shun-Ichi; Misaki, Yukiko; Yoshimura, Kazuki; Gomyo, Ayumi; Hayakawa, Jin; Tamaki, Masaharu; Akahoshi, Yu; Ugai, Tomotaka; Kameda, Kazuaki; Wada, Hidenori; Ishihara, Yuko; Kawamura, Koji; Sakamoto, Kana; Sato, Miki; Terasako-Saito, Kiriko; Kikuchi, Misato; Nakasone, Hideki; Kako, Shinichi; Tanihara, Aki; Kanda, Yoshinobu

    2018-03-27

    The actual heparin concentration of harvested allogeneic bone marrow varies among harvest centers. We monitor the activated partial thromboplastin time (APTT) of the patient during bone marrow infusion and administer prophylactic protamine according to the APTT. We retrospectively reviewed the charts of consecutive patients who underwent bone marrow transplantation without bone marrow processing at our center between April 2007 and March 2016 (n = 94). APTT was monitored during marrow transfusion in 52 patients. We analyzed the relationship between the APTT ratio and several parameters related to heparin administration. As a result, the weight-based heparin administration rate (U/kg/hour) seemed to be more closely related to the APTT ratio (r = .38, P = .005) than to the total amount of heparin. There was no significant correlation between the APTT ratio and renal or liver function. Bleeding complications during and early after infusion were seen in 3 of 52 patients, and included intracranial, nasal, and punctured-skin bleeding. The APTT ratio during transfusion was over 5.88 in the former 2 patients and 2.14 in the latter. All of these patients recovered without sequelae. In conclusion, slow bone marrow infusion is recommended to decrease the weight-based heparin administration rate when the heparin concentration per patient body weight is high. Copyright © 2018 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  4. Analytical characterization of heparin by capillary zone electrophoresis with conductivity detection and polymeric buffer additives.

    Science.gov (United States)

    Mikus, Peter; Valásková, Iva; Havránek, Emil

    2004-11-15

    A capillary zone electrophoresis (CZE) method for the analytical characterization of intact (high-molecular-weight) heparin was developed. For the first time, a hydrodynamically closed CZE separation system with conductivity detector was used for the separation, detection and quantitation of this highly sulfated, linear polysaccharide. Glycine (25mM) adjusted to pH 9.0 by bis-Tris-propane served as the running electrolyte system. Polymeric additives, polyvinylpyrrolidone (PVP), dextran (DEX), were used to improve the separation selectivity as they strongly retarded the heparin macromolecule while they did not practically influence comigrating inorganic anions. The proposed electrophoretic method was successfully validated. It was convenient for the sensitive, simple, rapid and reproducible assay of heparin in raw materials and isotonic saline. Here, the use of the conductivity detector was advantageous as it allowed heparin to be analyzed without a sample pretreatment. The CZE method should be an alternative to the pharmacopoeial conventional gel electrophoresis having used in the quality control of heparin so far. In addition, it should be convenient to quantitative estimation of heparin present in a preparation used, e.g., as the chiral selector in CE separations.

  5. In vitro effects of heparin and tissue factor pathway inhibitor on factor VII assays. possible implications for measurements in vivo after heparin therapy

    DEFF Research Database (Denmark)

    Bladbjerg, E-M; Larsen, L F; Ostergaard, P

    2000-01-01

    The coagulant activity of blood coagulation factor VII (FVII:C) can be lowered by changes in lifestyle and by therapeutic intervention, e.g. heparin infusion. The question is, however, whether FVII:C determined ex vivo is a valid measure of the FVII activity in vivo. We measured plasma FVII......:C, activated FVII (FVIIa), FVII protein (FVII:Ag), tissue factor pathway inhibitor (TFPI), triglycerides, and free fatty acids (FFA) before and 15 min after infusion of a bolus of unfractionated heparin (50 IU/kg body weight) in 12 healthy subjects. Additionally, we conducted in vitro experiments...

  6. Etanercept therapy for toxic epidermal necrolysis.

    Science.gov (United States)

    Paradisi, Andrea; Abeni, Damiano; Bergamo, Fabio; Ricci, Francesco; Didona, Dario; Didona, Biagio

    2014-08-01

    Toxic epidermal necrolysis (TEN) is a severe and potentially lethal drug reaction for which no standard treatment is available. To describe a case series of patients with TEN treated with a single dose of etanercept. We observed 10 consecutive patients with TEN. For each patient, we recorded the presence of comorbidities and all the drugs recently started (ie, in the last month). In all cases, 50 mg of etanercept was administered in a single subcutaneous injection. The clinical severity of disease was computed using the SCORe of Toxic Epidermal Necrosis (SCORTEN) scale. Using the probabilities of death linked to each level of SCORTEN score, we calculated the expected probability of death in our patients. Healing was defined as complete reepithelialization, and a time to healing curve was then obtained using the Kaplan-Meier method. All patients promptly responded to treatment, reaching complete reepithelialization without complications or side effects. The median time to healing was 8.5 days. This is a small, uncontrolled case series. These preliminary results suggest the possibility that tumor necrosis factor-alfa may be an effective target for control of TEN, a dangerous skin condition for which no effective cure has yet been found. Copyright © 2014 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

  7. Post-female-circumcision clitoral epidermal inclusion cyst: a case ...

    African Journals Online (AJOL)

    Keywords: complication, epidermal inclusion cyst, female circumcision. Pediatric Urology Division, Department of Urology, ... transplantation of the epidermis into the subcutaneous tissue with subsequent proliferation of epidermal ... The evolution of the practice of FGM, from being performed by traditional birth attendants to.

  8. Herbal medicines that benefit epidermal permeability barrier function

    Directory of Open Access Journals (Sweden)

    Lizhi Hu

    2015-06-01

    Full Text Available Epidermal permeability barrier function plays a critical role in regulating cutaneous functions. Hence, researchers have been searching for effective and affordable regimens to enhance epidermal permeability barrier function. In addition to topical stratum corneum lipids, peroxisome proliferator-activated receptor, and liver X receptor ligands, herbal medicines have been proven to benefit epidermal permeability barrier function in both normal and diseased skin, including atopic dermatitis, glucocorticoid-induced skin damage, and UVB-damaged skin. The potential mechanisms by which herbal medicines improve the permeability barrier include stimulation of epidermal differentiation, lipid production, antimicrobial peptide expression, and antioxidation. Therefore, utilization of herbal medicines could be a valuable alternative approach to enhance epidermal permeability barrier function in order to prevent and/or treat skin disorders associated with permeability barrier abnormalities.

  9. Genetic analysis of Ras genes in epidermal development and tumorigenesis

    Science.gov (United States)

    Drosten, Matthias; Lechuga, Carmen G; Barbacid, Mariano

    2013-01-01

    Proliferation and differentiation of epidermal keratinocytes are tightly controlled to ensure proper development and homeostasis of the epidermis. The Ras family of small GTPases has emerged as a central node in the coordination of cell proliferation in the epidermis. Recent genetic evidence from mouse models has revealed that the intensity of Ras signaling modulates the proliferative capacity of epidermal keratinocytes. Interfering with Ras signaling either by combined elimination of the 3 Ras genes from the basal layer of the epidermis or by overexpression of dominant-negative Ras isoforms caused epidermal thinning due to hypoproliferation of keratinocytes. In contrast, overexpression of oncogenic Ras mutants in different epidermal cell layers led to hyperproliferative phenotypes including the development of papillomas and squamous cell carcinomas. Here, we discuss the value of loss- and gain-of-function studies in mouse models to assess the role of Ras signaling in the control of epidermal proliferation. PMID:24150175

  10. Low-molecular-weight heparins: pharmacologic profile and product differentiation.

    Science.gov (United States)

    Fareed, J; Jeske, W; Hoppensteadt, D; Clarizio, R; Walenga, J M

    1998-09-10

    The interchangeability of low-molecular-weight heparins (LMWHs) has been the subject of discussion since these products were first introduced for the prophylaxis of deep vein thrombosis. Experimental evidence now exists to show that LMWHs differ from each other in a number of characteristics. Products have been differentiated on the basis of molecular weight and biologic properties, but only limited information derived from the clinical setting is available. Potency has been described on the basis of anti-Factor Xa activity, but at equivalent anti-Xa activities, the anti-Factor IIa activity of different products shows marked variations. At the relatively small doses used for the management of postsurgical deep vein thrombosis, the effect of these interproduct differences may be relatively minor, but as LMWHs are developed for therapeutic use at much higher doses, such differences may become clinically important. Variations in safety and efficacy reported in clinical trials of LMWHs may reflect the known differences in their molecular composition and pharmacologic properties.

  11. Molecular Weights of Bovine and Porcine Heparin Samples: Comparison of Chromatographic Methods and Results of a Collaborative Survey

    Directory of Open Access Journals (Sweden)

    Sabrina Bertini

    2017-07-01

    Full Text Available In a collaborative study involving six laboratories in the USA, Europe, and India the molecular weight distributions of a panel of heparin sodium samples were determined, in order to compare heparin sodium of bovine intestinal origin with that of bovine lung and porcine intestinal origin. Porcine samples met the current criteria as laid out in the USP Heparin Sodium monograph. Bovine lung heparin samples had consistently lower average molecular weights. Bovine intestinal heparin was variable in molecular weight; some samples fell below the USP limits, some fell within these limits and others fell above the upper limits. These data will inform the establishment of pharmacopeial acceptance criteria for heparin sodium derived from bovine intestinal mucosa. The method for MW determination as described in the USP monograph uses a single, broad standard calibrant to characterize the chromatographic profile of heparin sodium on high-resolution silica-based GPC columns. These columns may be short-lived in some laboratories. Using the panel of samples described above, methods based on the use of robust polymer-based columns have been developed. In addition to the use of the USP’s broad standard calibrant for heparin sodium with these columns, a set of conditions have been devised that allow light-scattering detected molecular weight characterization of heparin sodium, giving results that agree well with the monograph method. These findings may facilitate the validation of variant chromatographic methods with some practical advantages over the USP monograph method.

  12. Convective Leakage Makes Heparin Locking of Central Venous Catheters Ineffective Within Seconds: Experimental Measurements in a Model Superior Vena Cava.

    Science.gov (United States)

    Barbour, Michael C; McGah, Patrick M; Ng, Chin H; Clark, Alicia M; Gow, Kenneth W; Aliseda, Alberto

    2015-01-01

    Central venous catheters (CVCs), placed in the superior vena cava (SVC) for hemodialysis or chemotherapy, are routinely filled while not in use with heparin, an anticoagulant, to maintain patency and prevent thrombus formation at the catheter tip. The heparin-locking procedure, however, places the patient at risk for systemic bleeding, as heparin is known to leak from the catheter into the blood stream. We provide evidence from detailed in vitro experiments that shows the driving mechanism behind heparin leakage to be convective-diffusive transport due to the pulsatile flow surrounding the catheter. This novel mechanism is supported by experimental planar laser-induced fluorescence (PLIF) and particle image velocimetry (PIV) measurements of flow velocity and heparin transport from a CVC placed inside a model SVC inside a pulsatile flow loop. The results predict an initial, fast (<10 s), convection-dominated phase that rapidly depletes the concentration of heparin in the near-tip region, the region of the catheter with side holes. This is followed by a slow, diffusion-limited phase inside the catheter lumen, where the concentration is still high, that is insufficient at replenishing the lost heparin concentration in the near-tip region. The results presented here, which are consistent with previous in vivo estimates of 24 hour leakage rates, predict that the concentration of heparin in the near-tip region is essentially zero for the majority of the interdialytic phase, rendering the heparin locking procedure ineffective.

  13. Molecular Weights of Bovine and Porcine Heparin Samples: Comparison of Chromatographic Methods and Results of a Collaborative Survey.

    Science.gov (United States)

    Bertini, Sabrina; Risi, Giulia; Guerrini, Marco; Carrick, Kevin; Szajek, Anita Y; Mulloy, Barbara

    2017-07-19

    In a collaborative study involving six laboratories in the USA, Europe, and India the molecular weight distributions of a panel of heparin sodium samples were determined, in order to compare heparin sodium of bovine intestinal origin with that of bovine lung and porcine intestinal origin. Porcine samples met the current criteria as laid out in the USP Heparin Sodium monograph. Bovine lung heparin samples had consistently lower average molecular weights. Bovine intestinal heparin was variable in molecular weight; some samples fell below the USP limits, some fell within these limits and others fell above the upper limits. These data will inform the establishment of pharmacopeial acceptance criteria for heparin sodium derived from bovine intestinal mucosa. The method for MW determination as described in the USP monograph uses a single, broad standard calibrant to characterize the chromatographic profile of heparin sodium on high-resolution silica-based GPC columns. These columns may be short-lived in some laboratories. Using the panel of samples described above, methods based on the use of robust polymer-based columns have been developed. In addition to the use of the USP's broad standard calibrant for heparin sodium with these columns, a set of conditions have been devised that allow light-scattering detected molecular weight characterization of heparin sodium, giving results that agree well with the monograph method. These findings may facilitate the validation of variant chromatographic methods with some practical advantages over the USP monograph method.

  14. Cost-utility of enoxaparin compared with unfractionated heparin in unstable coronary artery disease

    Directory of Open Access Journals (Sweden)

    Milne Ruairidh

    2001-10-01

    Full Text Available Abstract Background Low molecular weight heparins hold several advantages over unfractionated heparin including convenience of administration. Enoxaparin is one such heparin licensed in the UK for use in unstable coronary artery disease (unstable stable angina and non-Q wave myocardial infarction. In these patients, two large randomised controlled trials and their meta-analysis showed small benefits for enoxaparin over unfractionated heparin at 30–43 days and potentially at one year. We found no relevant published full economic evaluations, only cost studies, one of which was conducted in the UK. The other studies, from the US, Canada and France, are difficult to interpret since their resource use and costs may not reflect UK practice. Methods We aimed to compare the benefits and costs of short-term treatment (two to eight days with enoxaparin and unfractionated heparin in unstable coronary artery disease. We used published data sources to estimate the incremental cost per quality adjusted life year (QALY, adopting a NHS perspective and using 1998 prices. Results The base case was a 0.013 QALY gain and net cost saving of £317 per person treated with enoxaparin instead of unfractionated heparin. All but one sensitivity analysis showed net savings and QALY gains, the exception (the worst case being a cost per QALY of £3,305. Best cases were a £495 saving and 0.013 QALY gain, or a £317 saving and 0.014 QALY gain per person. Conclusions Enoxaparin appears cost saving compared with unfractionated heparin in patients with unstable coronary artery disease. However, cost implications depend on local revascularisation practice.

  15. Effects of heparin on platelet aggregation and release and thromboxane A2 production

    International Nuclear Information System (INIS)

    Mohammad, S.F.; Anderson, W.H.; Smith, J.B.; Chuang, H.Y.; Mason, R.G.

    1981-01-01

    Heparin, when added to citrated platelet-rich plasma (PRP), caused potentiation of platelet aggregation and the release reaction induced by the aggregating agents adenosine diphosphate (ADP), arachidonic acid, collagen, and epinephrine. At low concentrations (4.7 x 10(-5) M) arachidonic acid failed to cause aggregation of platelets in citrated PRP. However, in the presence of heparin, the same concentration of arachidonic acid caused aggregation. Examination of PRP for the presence of thromboxane A2 (TxA2) by use of a bioassay revealed that heparin also stimulated release of TxA2. This finding indicated that platelets released more TxA2 when they were challenged by low concentrations of arachidonic acid in the presence of heparin than in its absence. Platelets were labeled with 3 H-arachidonic acid and 14 C-serotonin, and attempts were made to determine whether heparin stimulated the platelet release reaction first with subsequent increased production of TxA2, or alternatively, whether heparin stimulated TxA2 production first with subsequent enhancement of the release reaction. In view of the demonstrated simultaneous release of 14 C-serotonin and 3 H-arachidonic acid metabolites, it appeared that either release of 14 C and 3 H occurs concurrently or, even if one of these events is dependent on the other, both events take place in rapid succession. Timed sequential studies revealed that in the presence of arachidonic acid, the addition of heparin hastened the apparently simultaneous release of both 14 C and 3 H

  16. Epidermal Growth Factor Receptor in Pancreatic Cancer

    International Nuclear Information System (INIS)

    Oliveira-Cunha, Melissa; Newman, William G.; Siriwardena, Ajith K.

    2011-01-01

    Pancreatic cancer is the fourth leading cause of cancer related death. The difficulty in detecting pancreatic cancer at an early stage, aggressiveness and the lack of effective therapy all contribute to the high mortality. Epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein, which is expressed in normal human tissues. It is a member of the tyrosine kinase family of growth factors receptors and is encoded by proto-oncogenes. Several studies have demonstrated that EGFR is over-expressed in pancreatic cancer. Over-expression correlates with more advanced disease, poor survival and the presence of metastases. Therefore, inhibition of the EGFR signaling pathway is an attractive therapeutic target. Although several combinations of EGFR inhibitors with chemotherapy demonstrate inhibition of tumor-induced angiogenesis, tumor cell apoptosis and regression in xenograft models, these benefits remain to be confirmed. Multimodality treatment incorporating EGFR-inhibition is emerging as a novel strategy in the treatment of pancreatic cancer

  17. Study of the Efficacy, Safety and Tolerability of Low-Molecular-Weight Heparin vs. Unfractionated Heparin as Bridging Therapy in Patients with Embolic Stroke due to Atrial Fibrillation.

    Science.gov (United States)

    Feiz, Farnia; Sedghi, Reyhane; Salehi, Alireza; Hatam, Nahid; Bahmei, Jamshid; Borhani-Haghighi, Afshin

    2016-06-01

    Anticoagulation with adjusted dose warfarin is a well-accepted treatment for the prevention of recurrent stroke in patients with atrial fibrillation. Meanwhile, using bridging therapy with heparin or heparinoids before warfarin for initiation of anticoagulation is a matter of debate. We compared safety, efficacy, and tolerability of low-molecular-weight heparin (LMWH) and unfractionated heparin (UFH) as a bridging method in patients with recent ischemic stroke due to atrial fibrillation. This study was a randomized single-blind controlled trial in patients with acute ischemic stroke due to atrial fibrillation who were eligible for receiving warfarin and were randomly treated with 60 milligrams (mg) of LMWH (enoxaparin) subcutaneously every 12 h, or 1000 units/h of continuous intravenous heparin. The primary efficacy endpoints were recurrence of new ischemic stroke, myocardial infarction and/or death. The primary safety endpoint was central nervous system and/or systemic bleeding. Seventy-four subjects were recruited. Baseline demographic and clinical characteristics of two groups were matched. Composite endpoint outcome of new ischemic stroke, myocardial infarction, and/or death in follow-up period was seen in 10 subjects (27.03%) in UFH group and in four subjects (10.81%) in LMWH group (p value: 0.136). All hemorrhages and symptomatic central nervous system (CNS) hemorrhages in follow-up period were in 7 (18.9%) and 4 (10.8%) patients in UFH group, in 5 (13.5%), and 3 (8.1%) patients in LMWH group (p values: 0.754 and 0.751), respectively. Drop out and major adverse-effects such as heparin-induced thrombocytopenia and drug hypersensitivity were not seen in any patient. Enoxaparin can be a safe and efficient alternative for UFH as bridging therapy.

  18. Does epidermal growth factor play a role in the action of sucralfate?

    DEFF Research Database (Denmark)

    Nexø, Ebba; Poulsen, Steen Seier

    1987-01-01

    Epidermal growth factor (EGF) is a mitogenic peptide synthesized in the submandibular glands and released in saliva. EGF is able to prevent the development of gastrointestinal ulcers in the rat and to accelerate their healing. The present work was undertaken to examine whether Sucralfate acts via...... the effector system of EGF. We conclude that Sucralfate does not change the binding of EGF to its receptor, but it is able to bind EGF in a pH dependent manner and at pH below 4.5 virtually all EGF is bound to Sucralfate. In vivo studies in rats with acid-induced gastric ulcers show that sucralfate carries EGF...... to the ulcer, and that EGF is available for a longer period of time (3 hours) when EGF and Sucralfate are is given together than when EGF is given alone....

  19. Prevention of fatal postoperative pulmonary embolism by low doses of heparin. An international multicentre trial.

    Science.gov (United States)

    1975-07-12

    The efficacy of low-dose heparin in preventing fatal postoperative pulmonary embolism has been investigated in a multicentre prospective randomised trial. 4121 patients over the age of forty years undergoing a variety of elective major surgical procedures were included in the trial; 2076 of these were in the control group and 2045 patients received heparin. The two groups were well matched for age, sex, weight, blood-group, and other factors which could predispose to the development of venous thromboembolism. 180 (4-4 %) patients died during the postoperative period, 100 in the control and 80 in the heparin group: 72% of deaths in the control and 66% in the heparin group had necropsy examination. 16 patients in the control group and 2 in the heparin group were found at necropsy to have died due to acute massive pulmonary embolism (P smaller than 0-005). In addition, emboli found at necropsy in 6 patients in the control group and 3 in the heparin group were considered either contributory to death or an incidental finding since death in these patients was attributed to other causes. Taking all pulmonary emboli together, the findings were again significant (P smaller than 0-005). Of 1292 patients in whom the 125-I-fibrinogen test was performed to detect deep-vein thrombosis (D.V.T.) 667 were in the control group and 625 in the heparin group. The frequency of isotopic D.V.T. was reduced from 24-6% in the control group 7-7% in the heparin group (P smaller 0-005). In 30 patients D.V.T. was detected at necropsy; 24 in the control and 6 in the heparin group (P smaller 0-005). 32 patients in the control group and 11 in the heparin group developed clinically diagnosed D.V.T. which was confirmed by venography (P smaller than 0-005). In addition, 24 patients in the control and 8 in the heparin group were treated for clinically suspected pulmonary emoblism. The difference in the number of patients requiring treatment for D.V.T. and/or pulmonary embolism in the two groups was

  20. Morbidity associated with heparin therapy in spinal surgery patients with cardiovascular diseases

    International Nuclear Information System (INIS)

    Sawakami, Kimihiko; Ishikawa, Seiichi; Ito, Takui

    2011-01-01

    The objectives of this study were to investigate morbidity associated with heparin therapy in spinal surgery patients. The management of patients on anticoagulant therapy who undergo spinal surgery is becoming a common clinical problem. Although guidelines for the management of gastrointestinal endoscopy patients on heparin therapy have been published, spinal surgery may lead to specific complications, especially because of heparin therapy. However, only few studies have examined the clinical significance of heparin therapy in spinal surgery patients. The subjects of this study were 116 consecutive patients who were on anticoagulant or antiplatelet therapy. This says that all of the patients were receiving heparin or another anticoagunt. The patients were divided into 2 groups: a group that received heparin therapy before and after surgery (H group, n=25) and a group that did not receive heparin therapy (NH group, n=91). The results of clinical examinations and magnetic resonance imaging (MRI) in the 2 groups were compared. There were no significant differences between the 2 groups in baseline data. Comorbidities in both groups included valvular heart disease, atrial fibrillation, angina pectoris/myocardial infarction, and cerebral infarction. Mean intraoperative and postoperative blood loss in the H group were 324 ml and 536 ml, respectively, and the corresponding values in the NH group were 431 ml and 449 ml, respectively. MRI of all patients was performed within 10 days after surgery and T2-weighted images in the axial plane were examined for evidence of an epidural hematoma. Although the proportion of patients with an epidural hematoma, detected by MRI was higher in the H group than in the NH group (71% vs. 64%), none of the patients in either group required revision surgery because of intolerable pain or muscle weakness. Thrombocytopenia and skin necrosis were observed as complications of the heparin therapy in 1 patient in the H group (4%). The rate of

  1. Preparation and characterization of chitosan-heparin composite matrices for blood contacting tissue engineering

    International Nuclear Information System (INIS)

    He Qing; Gong Kai; Gong Yandao; Zhang Xiufang; Ao Qiang; Zhang Lihai; Hu Min

    2010-01-01

    Chitosan has been widely used for biomaterial scaffolds in tissue engineering because of its good mechanical properties and cytocompatibility. However, the poor blood compatibility of chitosan has greatly limited its biomedical utilization, especially for blood contacting tissue engineering. In this study, we exploited a polymer blending procedure to heparinize the chitosan material under simple and mild conditions to improve its antithrombogenic property. By an optimized procedure, a macroscopically homogeneous chitosan-heparin (Chi-Hep) blended suspension was obtained, with which Chi-Hep composite films and porous scaffolds were fabricated. X-ray photoelectron spectroscopy and sulfur elemental analysis confirmed the successful immobilization of heparin in the composite matrices (i.e. films and porous scaffolds). Toluidine blue staining indicated that heparin was distributed homogeneously in the composite matrices. Only a small amount of heparin was released from the matrices during incubation in normal saline for 10 days. The composite matrices showed improved blood compatibility, as well as good mechanical properties and endothelial cell compatibility. These results suggest that the Chi-Hep composite matrices are promising candidates for blood contacting tissue engineering.

  2. Laboratory tests for identification or exclusion of heparin induced thrombocytopenia: HIT or miss?

    Science.gov (United States)

    Favaloro, Emmanuel J

    2018-02-01

    Heparin induced thrombocytopenia (HIT) is a potentially fatal condition that arises subsequent to formation of antibodies against complexes containing heparin, usually platelet-factor 4-heparin ("anti-PF4-heparin"). Assessment for HIT involves both clinical evaluation and, if indicated, laboratory testing for confirmation or exclusion, typically using an initial immunological assay ("screening"), and only if positive, a secondary functional assay for confirmation. Many different immunological and functional assays have been developed. The most common contemporary immunological assays comprise enzyme-linked immunosorbent assay [ELISA], chemiluminescence, lateral flow, and particle gel techniques. The most common functional assays measure platelet aggregation or platelet activation events (e.g., serotonin release assay; heparin-induced platelet activation (HIPA); flow cytometry). All assays have some sensitivity and specificity to HIT antibodies, but differ in terms of relative sensitivity and specificity for pathological HIT, as well as false negative and false positive error rate. This brief article overviews the different available laboratory methods, as well as providing a suggested approach to diagnosis or exclusion of HIT. © 2017 Wiley Periodicals, Inc.

  3. Hemocompatible ɛ-polylysine-heparin microparticles: A platform for detecting triglycerides in whole blood.

    Science.gov (United States)

    Xu, Tingting; Chi, Bo; Chu, Meilin; Zhang, Qicheng; Zhan, Shuyue; Shi, Rongjia; Xu, Hong; Mao, Chun

    2018-01-15

    Triglycerides are clinically important marker for atherosclerosis, heart disease and hypertension. Here, a platform for detecting triglycerides in whole blood directly was developed based on hemocompatible ɛ-polylysine-heparin microparticles. The obtained products of ɛ-polylysine-heparin microparticles were characterized by fourier transform infrared (FT-IR) spectra, transmission electron microscopy (TEM) and ζ-potential. Moreover, the blood compatibility of ɛ-polylysine-heparin microparticles was characterized by in vitro coagulation tests, hemolysis assay and whole blood adhesion tests. Considering of uniform particle size, good dispersibility and moderate long-term anticoagulation capability of the microparticles, a Lipase-(ɛ-polylysine-heparin)-glassy carbon electrode (GCE) was constructed to detect triglycerides. The proposed biosensor had good electrocatalytic activity towards triglycerides, in which case the sensitivity was 0.40μAmg -1 dLcm -2 and the detection limit was 4.67mgdL -1 (S/N = 3). Meanwhile, the Lipase-(ɛ-polylysine-heparin)-GCE electrode had strong anti-interference ability as well as a long shelf-life. Moreover, for the detection of triglycerides in whole blood directly, the detection limit was as low as 5.18mgdL -1 . The new constructed platform is suitable for detecting triglycerides in whole blood directly, which provides new analytical systems for clinical illness diagnosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Evidence for a saturable mechanism of disappearance of standard heparin in rabbits

    International Nuclear Information System (INIS)

    Boneu, B.; Caranobe, C.; Gabaig, A.M.; Dupouy, D.; Sie, P.; Buchanan, M.R.; Hirsh, J.

    1987-01-01

    This work demonstrates that after bolus intravenous injection standard heparin (SH) disappearance results from the combination of a saturable and a non saturable mechanism. Pharmacokinetics and pharmacodynamics of SH were studied by measuring the disappearance of increasing doses (5 - 500 anti-factor Xa U/kg) of 125 I-heparin and of its biological effects. CPM curves allowed the determination of the half lives of heparin according to the dose injected. The half lives were clearly dose dependent and reached a plateau over 100 anti-factor Xa U/kg. The complex curve which describes the amount of heparin cleared per time unit after any given dose has been resolved into its two components reflecting a saturable and a non saturable mechanism of disappearance. For the doses less than 100 anti-factor Xa U/kg the saturable mechanism was preeminent and the anti-factor Xa activity disappearance followed an exponential pattern; for the doses less than 100 anti-factor Xa U/kg the contribution of the non saturable mechanism becomes more important and the anti-factor Xa activity disappearance followed a concave-convex pattern. Further experiments showed that the heparin half life shortened as the circulating anti-factor Xa activity decreased; this phenomenon may explain the concave-convex pattern of the curve of the anticoagulant effect observed after injection of large doses of SH

  5. Effect of heparin calcium different concentrations on some physical properties and structure in polyacrylamide matrix

    International Nuclear Information System (INIS)

    Abdelrazek, E.M.; Ibrahim, Hosam S.

    2010-01-01

    Films of polyacrylamide (PAAm) doped with different concentrations of heparin calcium, from 0.0 to 8 wt%, have been prepared by casting method. Studies were carried out utilizing X-ray, FT-IR, UV/VIS, DSC and DC electrical conduction to characterize the structural, optical and thermal properties of the films. Results revealed that the structural and chemical characterizations of PAAm films are affected by the addition of heparin calcium content. XRD spectra revealed that the amorphous phases increase with increase in filling levels of heparin (FLs). FT-IR analysis revealed that incorporation of heparin calcium leads to a small modification in the spectra of films. The optical absorption spectra in the UV/VIS region revealed structural variation increases with increase in concentration, which is reflected in the form of decrease in the energy band gap E g . Significant changes of DSC curves of the films suggest that strong interaction established between heparin calcium and PAAm molecules. The DC electric conduction data were interpreted on the basis of an intrachain one-dimensional interpolaron hopping model of Kuivalainen.

  6. Heparin-Induced Thrombocytopenia in a Patient with Essential Thrombocythemia: A Case Based Update

    Directory of Open Access Journals (Sweden)

    Edva Noel

    2015-01-01

    Full Text Available Vascular thrombosis is a common clinical feature of both essential thrombocythemia (ET and heparin-induced thrombocytopenia (HIT. The development of HIT in a patient with ET is rare and underrecognized. We report the case of a 77-year-old woman with preexisting ET, who was admitted with acute coronary syndrome, and IV heparin was started. She was exposed to unfractionated heparin (UFH 5 days prior to this admission. Decrease in platelet count was noted, and HIT panel was sent. Heparin was discontinued. Patient developed atrial fibrillation, and Dabigatran was started. On day three, patient also developed multiple tiny cerebral infarctions and acute right popliteal DVT. On day ten of admission, HIT panel was positive, and Dabigatran was changed to Lepirudin. Two days later, Lepirudin was also discontinued because patient developed pseudoaneurysm on the right common femoral artery at the site of cardiac catheterization access. A progressive increase in the platelet count was noted after discontinuing heparin. Physicians should be aware of the coexistence of HIT and ET, accompanied challenges of the prompt diagnosis, and initiation of appropriate treatment.

  7. Nycthemeral variations of 99Tcsup(m)-labelled heparin pharmacokinetic parameters

    International Nuclear Information System (INIS)

    Decousus, M.; Gremillet, E.; Decousus, H.; Champailler, A.; Houzard, C.; Perpoint, B.; Jaubert, J.

    1985-01-01

    Six healthy volunteers received four i.v.boluses of 99 Tcsup(m)-heparin at 8.00, 14.00, 20.00 and 02.00 hours at seven-day intervals. Nine blood samples were taken covering a period of 2 h after administration. Simultaneously urine was collected and diuresis not noted. Plasma and urinary radioactivity were measured and standard pharmacokinetic parameters were calculated. Nycthemeral variations of these kinetic parameters were detected by means of distribution-free tests. Circadian rhythms were analysed by means of the cosinor method and the Gauss-Marquardt method. The mean raw value of the following parameters: apparent volume of distribution, plasmatic clearance and extra-renal metabolic clearance, increased significantly between 8.00 and 14.00 and decreased between 14.00 and 20.00. A circadian rhythm was found for the plasmatic clearance only. On the other hand the elimination half-lives and the renal clearance were unaffected by the time of the injections. These results obtained for low doses of 99 Tcsup(m)-heparin suggest a circadian rhythm of the bio-availability of heparin in man. This fact should be taken into account for the use of 99 Tcsup(m)-heparin in the diagnosis of deep-vein thrombosis and for the safe adjustment of the heparin dosages in the treatment of severe thromboembolism. (author)

  8. Heparin-induced increase in serum levels of aminotranferases. A controlled clinical trial.

    Science.gov (United States)

    Nielsen, H K; Husted, S E; Koopmann, H D; Fasting, H; Simonsen, O; Andersen, K; Husegaard, H C; Petersen, T K

    1984-01-01

    Sixty-four patients over the age of 40 years, undergoing elective surgery of at least one hour's duration, were randomized to treatment with either a thromboembolic deterrent ( TED ) stocking (Kendall Co.) or subcutaneous low-dose heparin 5 000 IU every 12 hours. Serum levels of alanine aminotransferase (S-ALAT), aspartate aminotransferase (S-ASAT), gamma-glutamyl transpeptidase (S-gamma-GT) and alkaline phosphatase (S-ALP) were measured. S-ALAT increased significantly on the 5th and 10th postoperative day, from 27 +/- 2 (x +/- SE) to 40 +/- 4 (p less than 0.01) and 55 +/- 7 U/l (p less than 0.001), respectively, in the heparin group and was significantly higher in the heparin than in the TED group both on the 5th (p less than 0.01) and 10th (p less than 0.05) postoperative day. S-ASAT and S-gamma-GT increased significantly during heparin treatment, but did not differ significantly from the values of the TED group. No change in S-ALP was registered in either group. It is concluded that prophylactic treatment with low-dose heparin induces a significant increase in S-aminotransferase levels, especially in S-ALAT. The phenomenon has profound differential diagnostic implications in conditions such as pulmonary embolism and acute myocardial infarction.

  9. Assessment of Heparin Anticoagulation Measured Using i-STAT and Hemochron Activated Clotting Time.

    Science.gov (United States)

    Maslow, Andrew; Chambers, Alison; Cheves, Tracey; Sweeney, Joseph

    2018-01-31

    Adequate anticoagulation, measured using activated clotting time (ACT), is important during vascular and cardiac surgeries. Unfractionated heparin is the most common anticoagulant used. The purpose of this analysis was to compare the i-STAT ACT (iACT) to the Hemochron ACT (hACT), both of which were then compared to anti-factor Xa (anti-Xa) assay, a representation of heparin level and activity. Prospective study. Tertiary care cardiovascular center. Eleven consecutive elective adult cardiac surgical patients. Prior to cardiopulmonary bypass, ACTs were measured using i-STAT and Hemochron technologies and compared to each other and to anti-Xa assay prior to and during a cumulative administration of heparin. Data were compared using bias analyses. Heparin (300 U/kg) was administered in quarterly doses. Coagulation labs were collected prior to and 3 minutes after each quarterly dose of heparin. The baseline ACTs for i-STAT and Hemochron were 147 and 142 seconds, respectively. A significant association was found between iACT and hACT (p = 0.002). The iACT measurements underestimated hACT at ACT levels >180 seconds or anti-Xa levels >0.75 U/mL. No significant difference was found between ACT data at anti-Xa levels 0.75 U/mL. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. The role of heparin in sepsis: much more than just an anticoagulant.

    Science.gov (United States)

    Li, Xu; Ma, Xiaochun

    2017-11-01

    Despite progress in antibiotic treatment, mechanical ventilation, fluid resuscitation and blood glucose maintenance, sepsis remains a cause of high mortality in the intensive care unit to date, there are no proven treatment strategies for the routine management of septic patients. The extensive interaction between inflammation and coagulation contributes to the basic pathophysiology of sepsis. Thus, the agents that attenuate the activation of both inflammation and coagulation may improve the outcome in sepsis. Apart from the well-known anticoagulant effects of heparin, it also possesses various immunomodulatory properties and protects glycocalyx from shedding. Hence, heparin seems to be such an agent. Immunothrombosis plays an important role in early host defence against bacterial dissemination, thus the proper timing for anticoagulant therapy should be determined. We review the available experimental and clinical data supporting the use of heparin in sepsis. At this time the use of heparin in the treatment of sepsis is conflicting. Future trials of heparin therapy for sepsis should concentrate on the very severely ill patients, in whom benefit is most likely to be demonstrated. © 2017 John Wiley & Sons Ltd.

  11. Characterization of currently marketed heparin products: key tests for quality assurance.

    Science.gov (United States)

    Keire, David A; Ye, Hongping; Trehy, Michael L; Ye, Wei; Kolinski, Richard E; Westenberger, Benjamin J; Buhse, Lucinda F; Nasr, Moheb; Al-Hakim, Ali

    2011-01-01

    During the 2007-2008 heparin crisis, it was found that the United States Pharmacopeia (USP) testing monograph for unfractionated heparin sodium (UFH) did not detect the presence of the contaminant, oversulfated chondroitin sulfate (OSCS) in heparin. In response to this concern, new tests and specifications were developed by the Food and Drug Administration (FDA) and USP and put in place to not only detect the contaminant OSCS but also to improve assurance of quality and purity of the drug product. Additional tests were also developed to monitor the heparin supply chain for other possible economically motivated additives or impurities. In 2009, a new USP monograph was put in place that includes 500 MHz (1)H NMR, SAX-HPLC, %galactosamine in total hexosamine, and anticoagulation time assays with purified factor IIa or factor Xa. These tests represent orthogonal approaches for UFH identification, measurement of bioactivity, and for detection of process impurities or contaminants in UFH. The FDA has applied these analytical approaches to the study of UFH active pharmaceutical ingredients in the marketplace. Here, we describe results from a comprehensive survey of UFH collected from seven different sources after the 2009 monograph revision and compare these data with results obtained on other heparin samples collected during the 2007-2008 crisis.

  12. Spatiotemporal Expression of p63 in Mouse Epidermal Commitment

    Directory of Open Access Journals (Sweden)

    Qian Zhao

    2015-12-01

    Full Text Available The embryonic surface ectoderm is a simple flat epithelium consisting of cells that express the cytokeratins K8/K18. Before stratification, K5/K14 expression substitutes K8/K18 expression, marking the event called epidermal commitment. Previous studies show that the transcription factor p63 plays an essential role in epidermal commitment. However, detailed expression information of p63 during early epidermal development in mice is still unclear. We systematically studied the expression pattern of p63 in mouse epidermal commitment, together with K8 and K5. We show that p63 expression could be detected as early as E8.5 in mouse embryos preceding epidermal commitment. p63 expression first appears near the newly formed somites and the posterior part of the embryo, further expanding to the whole embryonic surface with particular enrichment in the first branchial arches and the limb buds. ΔNp63 is the major class of isoforms expressed in this period. Relative expression intensity of p63 depends on the embryonic position. In summary, there is a sequential and regular expression pattern of K8, p63 and K5 in mouse epidermal commitment. Our study not only contributes to understanding the early events during epidermal development but also provides a basal tool to study the function of p63 in mammals.

  13. Polymeric membranes modulate human keratinocyte differentiation in specific epidermal layers.

    Science.gov (United States)

    Salerno, Simona; Morelli, Sabrina; Giordano, Francesca; Gordano, Amalia; Bartolo, Loredana De

    2016-10-01

    In vitro models of human bioengineered skin substitutes are an alternative to animal experimentation for testing the effects and toxicity of drugs, cosmetics and pollutants. For the first time specific and distinct human epidermal strata were engineered by using membranes and keratinocytes. To this purpose, biodegradable membranes of chitosan (CHT), polycaprolactone (PCL) and a polymeric blend of CHT-PCL were prepared by phase-inversion technique and characterized in order to evaluate their morphological, physico-chemical and mechanical properties. The capability of membranes to modulate keratinocyte differentiation inducing specific interactions in epidermal membrane systems was investigated. The overall results demonstrated that the membrane properties strongly influence the cell morpho-functional behaviour of human keratinocytes, modulating their terminal differentiation, with the creation of specific epidermal strata or a fully proliferative epidermal multilayer system. In particular, human keratinocytes adhered on CHT and CHT-PCL membranes, forming the structure of the epidermal top layers, such as the corneum and granulosum strata, characterized by withdrawal or reduction from the cell cycle and cell proliferation. On the PCL membrane, keratinocytes developed an epidermal basal lamina, with high proliferating cells that stratified and migrated over time to form a complete differentiating epidermal multilayer system. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Epidermal stem cells: location, potential and contribution to cancer.

    Science.gov (United States)

    Ambler, C A; Määttä, A

    2009-01-01

    Epidermal stem cells have been classically characterized as slow-cycling, long-lived cells that reside in discrete niches in the skin. Gene expression studies of niche-resident cells have revealed a number of stem cell markers and regulators, including the Wnt/beta-catenin, Notch, p63, c-Myc and Hedgehog pathways. A new study challenges the traditional developmental paradigm of slow-cycling stem cells and rapid-cycling transit amplifying cells in some epidermal regions, and there is mounting evidence to suggest that multi-lineage epidermal progenitors can be isolated from highly proliferative, non-niche regions. Whether there is a unique microenvironment surrounding these progenitors remains to be determined. Interestingly, cancer stem cells derived from epidermal tumours exist independent of the classic skin stem cell niche, yet also have stem cell properties, including multi-lineage differentiation. This review summarizes recent studies identifying the location and regulators of mouse and human epidermal stem cells and highlights the strategies used to identify cancer stem cells, including expression of normal epidermal stem cell markers, expression of cancer stem cell markers identified in other epidermal tumours and characterization of side-population tumour cells.

  15. E-cadherin homophilic ligation inhibits cell growth and epidermal growth factor receptor signaling independently of other cell interactions

    DEFF Research Database (Denmark)

    Perrais, Michaël; Chen, Xiao; Perez-Moreno, Mirna

    2007-01-01

    growth inhibitory signals. To address this question, we have selectively formed E-cadherin homophilic bonds at the cell surface of isolated epithelial cells by using functionally active recombinant E-cadherin protein attached to microspheres. We find that E-cadherin ligation alone reduces the frequency...... of cells entering the S phase, demonstrating that E-cadherin ligation directly transduces growth inhibitory signals. E-cadherin binding to beta-catenin is required for cell growth inhibition, but beta-catenin/T-cell factor transcriptional activity is not involved in growth inhibition resulting from...... homophilic binding. Neither E-cadherin binding to p120-catenin nor beta-catenin binding to alpha-catenin, and thereby the actin cytoskeleton, is required for growth inhibition. E-cadherin ligation also inhibits epidermal growth factor (EGF) receptor-mediated growth signaling by a beta...

  16. Analysis of the complex formation of heparin with protamine by light scattering and analytical ultracentrifugation: implications for blood coagulation management.

    Science.gov (United States)

    Maurer, Jürgen; Haselbach, Stephanie; Klein, Oliver; Baykut, Doan; Vogel, Vitali; Mäntele, Werner

    2011-02-02

    Heparin, a linear glycosaminoglycan, is used in different forms in anticoagulation treatment. Protamine, a highly positive charged peptide containing about 32 amino acids, acts as an antagonist for heparin to restore normal blood coagulation. The complex formation of protamine with heparin was analyzed by a combination of analytical ultracentrifugation and light scattering. Titration of heparin with protamine in blood plasma preparations results in a drastic increase of turbidity, indicating the formation of nanoscale particles. A similar increase of turbidity was observed in physiological saline solution with or without human serum albumin (HSA). Particle size analysis by analytical ultracentrifugation revealed a particle radius of approximately 30 nm for unfractionated heparin and of approximately 60 nm for low molecular weight heparin upon complexation with excess protamine, in agreement with atomic force microscopy data. In the absence of HSA, larger and more heterogeneous particles were observed. The particles obtained were found to be stable for hours. The particle formation kinetics was analyzed by light scattering at different scattering angles and was found to be complete within several minutes. The time course of particle formation suggests a condensation reaction, with sigmoidal traces for low heparin concentrations and quasi-first-order reaction for high heparin concentrations. Under all conditions, the final scattering intensity reached after several minutes was found to be proportional to the amount of heparin in the blood plasma or buffer solution, provided that excess protamine was available and no multiple scattering occurred. On the basis of a direct relation between particle concentration and the heparin concentration present before protaminization, a light scattering assay was developed which permits the quantitative analysis of the heparin concentration in blood plasma and which could complement or even replace the activated clotting time test

  17. Thyroid hormone regulation of epidermal growth factor receptor levels in mouse mammary glands

    International Nuclear Information System (INIS)

    Vonderhaar, B.K.; Tang, E.; Lyster, R.R.; Nascimento, M.C.

    1986-01-01

    The specific binding of iodinated epidermal growth factor ([ 125 I]iodo-EGF) to membranes prepared from the mammary glands and spontaneous breast tumors of euthyroid and hypothyroid mice was measured in order to determine whether thyroid hormones regulate the EGF receptor levels in vivo. Membranes from hypothyroid mammary glands of mice at various developmental ages bound 50-65% less EGF than those of age-matched euthyroid controls. Treatment of hypothyroid mice with L-T4 before killing restored binding to the euthyroid control level. Spontaneous breast tumors arising in hypothyroid mice also bound 30-40% less EGF than tumors from euthyroid animals even after in vitro desaturation of the membranes of endogenous growth factors with 3 M MgCl2 treatment. The decrease in binding in hypothyroid membranes was due to a decrease in the number of binding sites, not to a change in affinity of the growth factor for its receptor, as determined by Scatchard analysis of the binding data. Both euthyroid and hypothyroid membranes bound EGF primarily to a single class of high affinity sites [dissociation constant (Kd) = 0.7-1.8 nM]. Euthyroid membranes bound 28.4 +/- (SE) 0.6 fmol/mg protein, whereas hypothyroid membranes bound 15.5 +/- 1.0 fmol/mg protein. These data indicate that EGF receptor levels in normal mammary glands and spontaneous breast tumors in mice are subject to regulation by thyroid status

  18. Biomedical Application of Low Molecular Weight Heparin/Protamine Nano/Micro Particles as Cell- and Growth Factor-Carriers and Coating Matrix

    Directory of Open Access Journals (Sweden)

    Masayuki Ishihara

    2015-05-01

    Full Text Available Low molecular weight heparin (LMWH/protamine (P nano/micro particles (N/MPs (LMWH/P N/MPs were applied as carriers for heparin-binding growth factors (GFs and for adhesive cells including adipose-derived stromal cells (ADSCs and bone marrow-derived mesenchymal stem cells (BMSCs. A mixture of LMWH and P yields a dispersion of N/MPs (100 nm–3 μm in diameter. LMWH/P N/MPs can be immobilized onto cell surfaces or extracellular matrix, control the release, activate GFs and protect various GFs. Furthermore, LMWH/P N/MPs can also bind to adhesive cell surfaces, inducing cells and LMWH/P N/MPs-aggregate formation. Those aggregates substantially promoted cellular viability, and induced vascularization and fibrous tissue formation in vivo. The LMWH/P N/MPs, in combination with ADSCs or BMSCs, are effective cell-carriers and are potential promising novel therapeutic agents for inducing vascularization and fibrous tissue formation in ischemic disease by transplantation of the ADSCs and LMWH/P N/MPs-aggregates. LMWH/P N/MPs can also bind to tissue culture plates and adsorb exogenous GFs or GFs from those cells. The LMWH/P N/MPs-coated matrix in the presence of GFs may provide novel biomaterials that can control cellular activity such as growth and differentiation. Furthermore, three-dimensional (3D cultures of cells including ADSCs and BMSCs using plasma-medium gel with LMWH/P N/MPs exhibited efficient cell proliferation. Thus, LMWH/P N/MPs are an adequate carrier both for GFs and for stromal cells such as ADSCs and BMSCs, and are a functional coating matrix for their cultures.

  19. UVB-induced epidermal hyperproliferation is modified by a single, topical treatment with a mitosis inhibitory epidermal pentapeptide

    International Nuclear Information System (INIS)

    Olsen, W.M.; Elgjo, K.

    1990-01-01

    A single application of a water-miscible cream base containing the recently identified mitosis inhibitory epidermal pentapeptide pyroGlu-Glu-Asp-Ser-GlyOH (EPP) to hairless mouse skin is followed by a long-lasting period of reduced epidermal cell proliferation. To examine if a similar growth inhibition could be achieved in stimulated and rapidly proliferating epidermis, EPP was applied at two different concentrations, 0.005 or 0.02%, to hairless mouse skin immediately after exposure of the left flank to an erythemic dose of ultraviolet B light (UVB). This dose of UVB alone induces a sustained period of rapid epidermal cell proliferation, starting at about 18 h after the irradiation. Epidermal cell proliferation was followed from 18 to 54 h (0.005% cream) or from 18 to 30 h (0.02% cream) after the treatment by estimating the rate of G2-M cell flux (the mitotic rate) by means of Colcemid, and epidermal DNA synthesis by counting labeled cells after pulse-labeling with 3H-thymidine. The unirradiated side of the mice was used as reference. The results showed that topical treatment with a 0.02% EPP cream partially inhibited UVB-induced epidermal hyperproliferation, while the 0.005% EPP cream inhibited as well as stimulated the UVB-induced hyperproliferation. Thus, EPP is effective even in rapidly proliferating epidermal cell populations, but the outcome is obviously dose-dependent in this test system

  20. Managing cancer-related venous thromboembolic disease: low-molecular-weight heparins and beyond.

    Science.gov (United States)

    O'Connell, Casey L; Liebman, Howard A

    2008-12-01

    Venous thromboembolism is a major contributor to the morbidity and mortality of patients with cancer. For patients undergoing cancer surgery, several trials support the safety and efficacy of unfractionated heparin and of low-molecular-weight heparin for the prevention of venous thromboembolism, while data regarding the efficacy and safety of these agents in the setting of medical hospitalization is less definitive and must be extracted from trials including noncancer patients with different thrombotic risk factors. Randomized clinical studies confirm that patients with cancer who develop venous thromboembolism have superior outcomes when treated with long-term low-molecular-weight heparin as compared with warfarin. Novel anticoagulants that are orally bioavailable and function by directly inhibiting factor Xa or thrombin are entering the market. To date, data regarding the efficacy and safety of these novel anticoagulants as venous thromboembolism prophylaxis and treatment in cancer patients are not available and must be extracted from larger trials with heterogeneous patient populations.

  1. Safety and Efficacy of Argatroban in the Management of Heparin-Induced Thrombocytopenia

    Directory of Open Access Journals (Sweden)

    Bernd Saugel

    2011-01-01

    Full Text Available Heparin-induced thrombocytopenia (HIT is a life-threatening adverse reaction to heparin therapy that is characterized by thrombocytopenia and an increased risk of venous and arterial thrombosis. According to guidelines, in patients with strongly suspected or confirmed HIT all sources of heparin have to be discontinued and an alternative, nonheparin anticoagulant for HIT treatment must immediately be started. For both the prophylaxis of thrombembolic events in HIT and the treatment of HIT with thrombosis the direct thrombin inhibitor argatroban is approved in the United States. The objective of this review is to describe the mechanism of action and the pharmacokinetic profile of argatroban, to characterize argatroban regarding its safety and therapeutic efficacy and to discuss its place in therapy in HIT.

  2. Platelet count recovery and seroreversion in immune HIT despite continuation of heparin: further observations and literature review.

    Science.gov (United States)

    Shih, Andrew W; Sheppard, Jo-Ann I; Warkentin, Theodore E

    2017-10-05

    One of the standard distinctions between type 1 (non-immune) and type 2 (immune-mediated) heparin-induced thrombocytopenia (HIT) is the transience of thrombocytopenia: type 1 HIT is viewed as early-onset and transient thrombocytopenia, with platelet count recovery despite continuing heparin administration. In contrast, type 2 HIT is viewed as later-onset (i. e., 5 days or later) thrombocytopenia in which it is generally believed that platelet count recovery will not occur unless heparin is discontinued. However, older reports of type 2 HIT sometimes did include the unexpected observation that platelet counts could recover despite continued heparin administration, although without information provided regarding changes in HIT antibody levels in association with platelet count recovery. In recent years, some reports of type 2 HIT have confirmed the observation that platelet count recovery can occur despite continuing heparin administration, with serological evidence of waning levels of HIT antibodies ("seroreversion"). We now report two additional patient cases of type 2 HIT with platelet count recovery despite ongoing therapeutic-dose (1 case) or prophylactic-dose (1 case) heparin administration, in which we demonstrate concomitant waning of HIT antibody levels. We further review the literature describing this phenomenon of HIT antibody seroreversion and platelet count recovery despite continuing heparin administration. Our observations add to the concept that HIT represents a remarkably transient immune response, including sometimes even when heparin is continued.

  3. Anticoagulant effects of inhaled unfractionated heparin in the dog as determined by partial thromboplastin time and factor Xa activity.

    Science.gov (United States)

    Manion, Jill S; Thomason, John M; Langston, Vernon C; Claude, Andrew K; Brooks, Marjory B; Mackin, Andrew J; Lunsford, Kari V

    2016-01-01

    To evaluate the anticoagulant effects of inhaled heparin in dogs. This study was conducted in 3 phases. In phase 1, bronchoalveolar lavage fluid (BALf) was collected to generate an in vitro calibration curve to relate heparin concentration to the activated partial thromboplastin time (aPTT). In phase 2, heparin was administered via nebulization to determine the threshold dose needed to prolong systemic aPTT. In phase 3, the local anticoagulant activity of inhaled heparin was determined by measurement of BALf anti-Xa activity and aPTT. University teaching hospital. Six healthy intact female Walker Hounds were used in this study. Two dogs were used for each phase. Inhaled unfractionated sodium heparin was administered in doses ranging from 50,000 to 200,000 IU. In vitro addition of heparin to BALf caused a prolongation in aPTT. Inhaled heparin at doses as high as 200,000 IU failed to prolong systemic aPTT, and a threshold dose could not be determined. No significant local anticoagulant effects were detected. Even at doses higher than those known to be effective in people, inhaled heparin appears to have no detectable local or systemic anticoagulant effects in dogs with the current delivery method. © Veterinary Emergency and Critical Care Society 2015.

  4. Safety and potential anticoagulant effects of nebulised heparin in burns patients with inhalational injury at Singapore General Hospital Burns Centre.

    Science.gov (United States)

    Yip, Lian Yee; Lim, Yen Fang; Chan, Hong Ngee

    2011-11-01

    Nebulised heparin, N-acetylcysteine (NAC) and salbutamol were shown to decrease reintubation rates, incidence of atelectasis and mortality in paediatric patients and reduce lung injury scores in adult burns patients with inhalational lung injury (ILI). Nebulised heparin, NAC and salbutamol treatment protocol was introduced in Singapore General Hospital (SGH) Burns Centre in 2006. However, safety data on the use of nebulised heparin and NAC for burns patients with ILI is not well established. In this study, we investigated the safety and potential anticoagulant effects of nebulised heparin in burns patients with ILI. A retrospective study with historical control was conducted. The treatment group consisted of 52 mechanically ventilated adult patients, with a diagnosis of ILI as confirmed by bronchoscopy, admitted to burn intensive care unit (BICU) from the year 2006 to 2009. The group was treated with nebulised heparin, NAC and salbutamol. The control group consists of 11 mechanically ventilated BICU ILI patients treated from year 2001 to 2005 before protocol initiation. Blood coagulation indices (prothrombin time (PT), activated partial thromboplastin time (APTT) and platelet count) were monitored and bleeding incidences were assessed. Blood coagulation indices did not suggest an increase risk of bleeding with nebulised heparin. The APTT, PT and platelet count followed a similar trend for both groups over 7 days. No clinically significant increase in bleeding risk was found to be associated with nebulised heparin. Nebulised heparin was not found to potentiate the risk of bleeding in burns patients with ILI. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

  5. The effect of heparin on pregnancy associated plasma protein-A concentration in healthy, non-pregnant individuals

    DEFF Research Database (Denmark)

    Jespersen, Camilla H B; Vestergaard, Kirstine R.; Schou, Morten

    2015-01-01

    Objectives: The objective of this study was to determine the differences in pregnancy associated plasma protein-A (PAPP-A) concentrations in heparin naive and heparin treated healthy men and non-pregnant women, to find a possible difference in different age groups, and to determine the response...

  6. Vitamin K antagonists or low-molecular-weight heparin for the long term treatment of symptomatic venous thromboembolism

    NARCIS (Netherlands)

    van der Heijden, J. F.; Hutten, B. A.; Büller, H. R.; Prins, M. H.

    2000-01-01

    Patients who have had an episode of symptomatic venous thromboembolism are usually treated for at least five days with intravenous unfractionated heparin or subcutaneous low-molecular-weight heparin. Thereafter, they received a three month course of a vitamin K antagonist, with a dose adjusted to

  7. Vascular access site complication in transfemoral coronary angiography between uninterrupted warfarin and heparin bridging.

    Science.gov (United States)

    Wongcharoen, Wanwarang; Pinyosamosorn, Kittipong; Gunaparn, Siriluck; Boonnayhun, Suchada; Thonghong, Tasalak; Suwannasom, Pannipa; Phrommintikul, Arintaya

    2017-08-01

    Warfarin discontinuation with heparin bridging is a common practice in patients receiving warfarin prior to elective coronary angiography (CAG). The uninterrupted warfarin strategy has been suggested to be alternative option for patients with high thromboembolic risk. Therefore, we aimed to assess the safety of elective transfemoral CAG during uninterrupted warfarin therapy compared to heparin bridging. This study was a randomized open-label design with blinded event evaluation. The 110 consecutive patients (age ≥ 18 years) receiving warfarin before the planned transfemoral CAG were randomly assigned to either heparin bridging or uninterrupted warfarin with targeted INR (2.0-3.0). The primary outcome was the incidence of major vascular access site complications. The baseline characteristics were comparable between two groups (mean age was 60.1 ± 7.8 years, 49 males). The mean INR on the day of CAG of heparin bridging and uninterrupted warfarin groups was 1.2 ± 0.3 and 2.2 ± 0.5 (P warfarin patients (P = 0.243). The total vascular access site complications occurred in 6 (10.9%) heparin-bridging and one (1.8%) uninterrupted warfarin patients (P = 0.113). No patient developed either other bleeding or thromboembolic events during 7 days after CAG. We demonstrated that an uninterrupted warfarin strategy did not increase vascular access site complications in patients undergoing transfemoral CAG compared to heparin bridging therapy. Due to the safety and the ease of uninterrupted warfarin strategy, this approach should be encouraged in patients receiving long-term warfarin who undergo elective transfemoral CAG. © 2017, Wiley Periodicals, Inc.

  8. High-throughput differentiation of heparin from other glycosaminoglycans by pyrolysis mass spectrometry.

    Science.gov (United States)

    Nemes, Peter; Hoover, William J; Keire, David A

    2013-08-06

    Sensors with high chemical specificity and enhanced sample throughput are vital to screening food products and medical devices for chemical or biochemical contaminants that may pose a threat to public health. For example, the rapid detection of oversulfated chondroitin sulfate (OSCS) in heparin could prevent reoccurrence of heparin adulteration that caused hundreds of severe adverse events including deaths worldwide in 2007-2008. Here, rapid pyrolysis is integrated with direct analysis in real time (DART) mass spectrometry to rapidly screen major glycosaminoglycans, including heparin, chondroitin sulfate A, dermatan sulfate, and OSCS. The results demonstrate that, compared to traditional liquid chromatography-based analyses, pyrolysis mass spectrometry achieved at least 250-fold higher sample throughput and was compatible with samples volume-limited to about 300 nL. Pyrolysis yielded an abundance of fragment ions (e.g., 150 different m/z species), many of which were specific to the parent compound. Using multivariate and statistical data analysis models, these data enabled facile differentiation of the glycosaminoglycans with high throughput. After method development was completed, authentically contaminated samples obtained during the heparin crisis by the FDA were analyzed in a blinded manner for OSCS contamination. The lower limit of differentiation and detection were 0.1% (w/w) OSCS in heparin and 100 ng/μL (20 ng) OSCS in water, respectively. For quantitative purposes the linear dynamic range spanned approximately 3 orders of magnitude. Moreover, this chemical readout was successfully employed to find clues in the manufacturing history of the heparin samples that can be used for surveillance purposes. The presented technology and data analysis protocols are anticipated to be readily adaptable to other chemical and biochemical agents and volume-limited samples.

  9. Fatal toxic epidermal necrolysis associated with minoxidil.

    Science.gov (United States)

    Karaoui, Lamis R; Chahine-Chakhtoura, Corinne

    2009-04-01

    Minoxidil is a direct-acting peripheral vasodilator for the treatment of symptomatic hypertension, or refractory hypertension associated with target organ damage, that is not manageable with a diuretic and two other antihypertensive drugs. The most frequent adverse events associated with minoxidil include hypertrichosis and cardiovascular events related to its powerful antihypertensive effect, and less frequently, rashes, bullous eruptions, and Stevens-Johnson syndrome (SJS). Evidence suggests that SJS and toxic epidermal necrolysis (TEN) are variants of a single disease with common causes and mechanisms, but differing severities. Epidermal detachment is mild in SJS, moderate in overlap SJS-TEN, and severe (> 30% of body surface area) in TEN. We describe a case of minoxidil-associated SJS that evolved into fatal TEN. A 69-year-old African-American woman with a history of chronic kidney disease was admitted to the hospital for a cerebrovascular accident and uncontrolled hypertension. On hospital day 12, oral minoxidil was added to her drug regimen. On day 23, she developed a maculopapular rash on her face that gradually diffused to her chest and back. Vesicles and papular lesions extended to her extremities and mucosal membranes; results of a skin biopsy revealed SJS. A positive Nikolsky's sign (blisters spread on application of pressure) was detected. On days 27-31, diffuse bullae developed with rash exacerbation. Skin detachment exceeded 30% and was consistent with TEN. The patient died on day 39. An evaluation of the causality and time course suggested that minoxidil was the most likely culpable drug, with a Naranjo adverse drug reaction probability scale score indicating that the likelihood of the association was possible (score of 3). The mechanism of this reaction has not been well elucidated. It may be related to an impaired clearance of the minoxidil metabolite, or an immune stimulation resulting in apoptosis and epidermis destruction. To our knowledge, this

  10. Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis ...

    African Journals Online (AJOL)

    REVIEW. Introduction. Stevens-Johnson syndrome (SJS) and toxic epidermal ... that affect the skin and mucous membranes. ... Open Access article distributed under the terms of the .... pathogenic components are removed from plasma. The.

  11. Epidermal and dermal integumentary structures of ankylosaurian dinosaurs.

    Science.gov (United States)

    Arbour, Victoria M; Burns, Michael E; Bell, Phil R; Currie, Philip J

    2014-01-01

    Ankylosaurian dinosaurs are most notable for their abundant and morphologically diverse osteoderms, which would have given them a spiky appearance in life. Isolated osteoderms are relatively common and provide important information about the structure of the ankylosaur dermis, but fossilized impressions of the soft-tissue epidermis of ankylosaurs are rare. Nevertheless, well-preserved integument exists on several ankylosaur fossils that shows osteoderms were covered by a single epidermal scale, but one or many millimeter-sized ossicles may be present under polygonal, basement epidermal scales. Evidence for the taxonomic utility of ankylosaurid epidermal scale architecture is presented for the first time. This study builds on previous osteological work that argues for a greater diversity of ankylosaurids in the Dinosaur Park Formation of Alberta than has been traditionally recognized and adds to the hypothesis that epidermal skin impressions are taxonomically relevant across diverse dinosaur clades. Copyright © 2013 Wiley Periodicals, Inc.

  12. "Cut-and-paste" manufacture of multiparametric epidermal electronic systems

    Science.gov (United States)

    Lu, Nanshu; Yang, Shixuan; Wang, Pulin

    2016-05-01

    Epidermal electronics is a class of noninvasive and unobstructive skin-mounted, tattoo-like sensors and electronics capable of vital sign monitoring and establishing human-machine interface. The high cost of manpower, materials, vacuum equipment, and photolithographic facilities associated with its manufacture greatly hinders the widespread use of disposable epidermal electronics. Here we report a cost and time effective, completely dry, benchtop "cut-and-paste" method for the freeform and portable manufacture of multiparametric epidermal sensor systems (ESS) within minutes. This versatile method works for all types of thin metal and polymeric sheets and is compatible with any tattoo adhesives or medical tapes. The resulting ESS are multimaterial and multifunctional and have been demonstrated to noninvasively but accurately measure electrophysiological signals, skin temperature, skin hydration, as well as respiratory rate. In addition, planar stretchable coils exploiting double-stranded serpentine design have been successfully applied as wireless, passive epidermal strain sensors.

  13. Predicting human epidermal melanin concentrations for different skin tones

    CSIR Research Space (South Africa)

    Smit, Jacoba E

    2011-07-01

    Full Text Available epidermal melanin concentrations for different skin tones JE Smit 1 , AE Karsten 2 , RW Sparrow 1 1 CSIR Biosciences, Pretoria, South Africa 2 CSIR National Laser Centre, Pretoria, South Africa Author e-mail address: KSmit...

  14. Epidermal Nevus Syndrome Associated with Brain Malformations and Medulloblastoma

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2013-01-01

    Full Text Available Researchers at Juntendo University and Tokyo Women’s Medical University, Japan; and University of California, San Francisco, Ca, report a male infant with epidermal nevus syndrome associated with brainstem and cerebellar malformations and neonatal medulloblastoma.

  15. A new approach for heparin standardization: combination of scanning UV spectroscopy, nuclear magnetic resonance and principal component analysis.

    Directory of Open Access Journals (Sweden)

    Marcelo A Lima

    Full Text Available The year 2007 was marked by widespread adverse clinical responses to heparin use, leading to a global recall of potentially affected heparin batches in 2008. Several analytical methods have since been developed to detect impurities in heparin preparations; however, many are costly and dependent on instrumentation with only limited accessibility. A method based on a simple UV-scanning assay, combined with principal component analysis (PCA, was developed to detect impurities, such as glycosaminoglycans, other complex polysaccharides and aromatic compounds, in heparin preparations. Results were confirmed by NMR spectroscopy. This approach provides an additional, sensitive tool to determine heparin purity and safety, even when NMR spectroscopy failed, requiring only standard laboratory equipment and computing facilities.

  16. The effect of heparin administration on the FT4-levels and on an unspecific peripheral thyroid parameter

    International Nuclear Information System (INIS)

    Eber, B.; Borkenstein, J.; Leb, G.

    1984-01-01

    Heparin produces changes in FT 4 -levels both in vivo and in vitro as determined by commercial kits. Methods utilising the principle of equilibrium dialysis show significant increases whereas methods using T 4 -tracer analogue techniques reveal marked decreases in FT 4 -values. Possible clinical side-effects of heparin administration such as heparin-induced hyperthyroidism and tachyarrhythmias are discussed. The present results confirm the FT 4 -decreasing effect of in vivo and in vitro administration of heparin with FT 4 -RIAs based on the tracer analogue technique; however, the unspecific peripheral thyroid parameter of systolic time-intervals did not reveal any tendency towards hyperthyroidism. Also the discrepant results dependent on the method used, indicate that, following heparin administration FT 4 -levels do not reflect that hormone concentration is relevant to the metabolism of the whole body. (orig.) [de

  17. The physiologic and therapeutic role of heparin in implantation and placentation

    Directory of Open Access Journals (Sweden)

    Michela Quaranta

    2015-01-01

    Full Text Available Implantation, trophoblast development and placentation are crucial processes in the establishment and development of normal pregnancy. Abnormalities of these processes can lead to pregnancy complications known as the great obstetrical syndromes: preeclampsia, intrauterine growth restriction, fetal demise, premature prelabor rupture of membranes, preterm labor, and recurrent pregnancy loss. There is mounting evidence regarding the physiological and therapeutic role of heparins in the establishment of normal gestation and as a modality for treatment and prevention of pregnancy complications. In this review, we will summarize the properties and the physiological contributions of heparins to the success of implantation, placentation and normal pregnancy.

  18. Heparin as a pharmacologic intervention to induce positive scintiscan in occult gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Chaudhuri, T.K.; Brantly, M.

    1984-01-01

    The value of using heparin as a pharmacologic intervention to induce a positive scintiscan was studied in a patient with chronic occult gastrointestinal bleeding. When all standard diagnostic tests (upper and lower gastrointestinal series, upper and lower endoscopy, and conventional noninterventional Tc-99m RBC imaging) fail to detect and localize gastrointestinal bleeding in a patient who has definite clinical evidence (guaiac positive stool and dropping hemoglobin, hematocrit) of chronic occult gastrointestinal oozing, heparin may be used (with proper precaution) as a last resort to aid in the scintigraphic detection and localization of chronic occult gastrointestinal bleeding

  19. Spurious hypocalcemia in hemodialysis patients after heparinization. In-vitro formation of calcium soaps.

    Science.gov (United States)

    Godolphin, W; Cameron, E C; Frohlich, J; Price, J D

    1979-02-01

    Patients on long-term hemodialysis via arteriovenous fistula received heparin when the fistula needle was inserted, before a sample of blood was obtained for chemical analysis. The resultant release of lipoprotein lipase activity in vivo and continued lipolytic activity in vitro sometimes produced sufficient free fatty acid to precipitate calcium soaps. The consequent spurious hypocalcemia was most frequently observed when the patients had chylomicronemia. This cause of apparent hypocalcemia was eliminated either by immediate analyses of the blood samples or by obtaining samples before systemic heparinization.

  20. Optimal allocation of leaf epidermal area for gas exchange

    OpenAIRE

    de Boer, Hugo J.; Price, Charles A.; Wagner-Cremer, Friederike; Dekker, Stefan C.; Franks, Peter J.; Veneklaas, Erik J.

    2016-01-01

    Summary A long?standing research focus in phytology has been to understand how plants allocate leaf epidermal space to stomata in order to achieve an economic balance between the plant's carbon needs and water use. Here, we present a quantitative theoretical framework to predict allometric relationships between morphological stomatal traits in relation to leaf gas exchange and the required allocation of epidermal area to stomata. Our theoretical framework was derived from first principles of ...

  1. Functionalization of chitosan/poly(lactic acid-glycolic acid) sintered microsphere scaffolds via surface heparinization for bone tissue engineering.

    Science.gov (United States)

    Jiang, Tao; Khan, Yusuf; Nair, Lakshmi S; Abdel-Fattah, Wafa I; Laurencin, Cato T

    2010-06-01

    Scaffolds exhibiting biological recognition and specificity play an important role in tissue engineering and regenerative medicine. The bioactivity of scaffolds in turn influences, directs, or manipulates cellular responses. In this study, chitosan/poly(lactic acid-co-glycolic acid) (chitosan/PLAGA) sintered microsphere scaffolds were functionalized via heparin immobilization. Heparin was successfully immobilized on chitosan/PLAGA scaffolds with controllable loading efficiency. Mechanical testing showed that heparinization of chitosan/PLAGA scaffolds did not significantly alter the mechanical properties and porous structures. In addition, the heparinized chitosan/PLAGA scaffolds possessed a compressive modulus of 403.98 +/- 19.53 MPa and a compressive strength of 9.83 +/- 0.94 MPa, which are in the range of human trabecular bone. Furthermore, the heparinized chitosan/PLAGA scaffolds had an interconnected porous structure with a total pore volume of 30.93 +/- 0.90% and a median pore size of 172.33 +/- 5.89 mum. The effect of immobilized heparin on osteoblast-like MC3T3-E1 cell growth was investigated. MC3T3-E1 cells proliferated three dimensionally throughout the porous structure of the scaffolds. Heparinized chitosan/PLAGA scaffolds with low heparin loading (1.7 microg/scaffold) were shown to be capable of stimulating MC3T3-E1 cell proliferation by MTS assay and cell differentiation as evidenced by elevated osteocalcin expression when compared with nonheparinized chitosan/PLAGA scaffold and chitosan/PLAGA scaffold with high heparin loading (14.1 microg/scaffold). This study demonstrated the potential of functionalizing chitosan/PLAGA scaffolds via heparinization with improved cell functions for bone tissue engineering applications.

  2. Investigation of a Potential Protective Mechanism Against Heparin-Induced Thrombocytopenia in Patients on Chronic Intermittent Hemodialysis

    Science.gov (United States)

    Tanhehco, Yvette C.; Cuker, Adam; Rudnick, Michael; Sachais, Bruce S.

    2015-01-01

    BACKGROUND Heparin-induced thrombocytopenia (HIT) develops as a result of platelet (PLT) activation by anti-platelet factor 4 (PF4)/heparin complex antibodies. Despite repeated exposure to heparin, patients undergoing chronic intermittent hemodialysis (HD) rarely develop HIT. We investigated the possibility that HD decreases/removes PF4 from PLT surfaces and/or plasma, thereby disfavoring immune complex formation as a mechanism of protection against HIT. MATERIALS AND METHODS We enrolled 20 patients undergoing chronic HD at the Penn Presbyterian Medical Center. Blood samples were drawn before, during and after treatment in the presence and absence of heparin. PF4, PF4/heparin antibody, heparin, and P-selectin levels were measured. RESULTS No patients demonstrated clinical symptoms of HIT. PLT surface PF4 levels decreased and plasma PF4 levels increased concurrently with increase in plasma heparin concentration. In the absence of heparin, PLT surface and plasma PF4 levels were unchanged. Anti-PF4/heparin antibodies, which were non-functional by the serotonin release assay, were detectable in 8 patients. PLT surface P-selectin levels did not change during treatment. CONCLUSIONS Removal of PLT surface and/or plasma PF4 as a mechanism of protection against HIT in patients undergoing HD is not supported by the results of our study, although the transient decrease in PLT surface PF4 in the presence of large amounts of heparin remains a candidate mechanism. The small sample size, single type of dialyzer membrane, and early sampling time points may have led to the inability to detect changes in PF4 levels. Future studies should explore other potential protective mechanisms. PMID:23305841

  3. In vitro binding of 67Ga to Ehrlich ascites tumor cells

    International Nuclear Information System (INIS)

    Kojima, S.; Kubodera, A.

    1984-01-01

    The binding of 67 Ga to Ehrlich ascites tumor cells (ETC) was studied in vitro. Acid mucopolysaccharide (AMPS) present at the cell surface of ETC was identified as heparan sulfate (HS). The extent of 67 Ga binding to ETC reached a plateau (ca. 10% of the added dose) at 1-2 h after the start of incubation. The binding was higher under neutral or alkaline conditions than under acidic conditions. Heparin and heparitinase treatment both significantly decreased the extent of 67 Ga binding to ETC. Mild treatment with protease, including trypsin or papain, also decreased the binding. On the contrary, the treatment with trypsin under severe conditions markedly increased the extent of 67 Ga binding to ETC. These results support the hypothesis that HS plays an important role as a 67 Ga receptor in the mechanism of gallium binding to ETC. (orig.)

  4. Species of /sup 67/Ga-binding acid mucopolysaccharide in liver

    Energy Technology Data Exchange (ETDEWEB)

    Ando, A.; Ando, I.

    1985-01-01

    It was determined from measuring neutral saccharide in the structure that the principal /sup 67/Ga-binding acid mucopolysaccharide in liver was keratan sulfate and/or keratan polysulfate. On the other hand, it was clarified from the results of mucopolysaccharase treatment that the main /sup 67/Ga-binding acid mucopolysaccharide in liver was neither keratan sulfate, heparan sulfate, heparin, nor chondroitin sulfate A, B and C. Based on the present results, it was deduced that the main /sup 67/Ga-binding acid mucopolysaccharide in liver was keratan polysulfate.

  5. Tight junction regulates epidermal calcium ion gradient and differentiation

    International Nuclear Information System (INIS)

    Kurasawa, Masumi; Maeda, Tetsuo; Oba, Ai; Yamamoto, Takuya; Sasaki, Hiroyuki

    2011-01-01

    Research highlights: → We disrupted epidermal tight junction barrier in reconstructed epidermis. → It altered Ca 2+ distribution and consequentially differentiation state as well. → Tight junction should affect epidermal homeostasis by maintaining Ca 2+ gradient. -- Abstract: It is well known that calcium ions (Ca 2+ ) induce keratinocyte differentiation. Ca 2+ distributes to form a vertical gradient that peaks at the stratum granulosum. It is thought that the stratum corneum (SC) forms the Ca 2+ gradient since it is considered the only permeability barrier in the skin. However, the epidermal tight junction (TJ) in the granulosum has recently been suggested to restrict molecular movement to assist the SC as a secondary barrier. The objective of this study was to clarify the contribution of the TJ to Ca 2+ gradient and epidermal differentiation in reconstructed human epidermis. When the epidermal TJ barrier was disrupted by sodium caprate treatment, Ca 2+ flux increased and the gradient changed in ion-capture cytochemistry images. Alterations of ultrastructures and proliferation/differentiation markers revealed that both hyperproliferation and precocious differentiation occurred regionally in the epidermis. These results suggest that the TJ plays a crucial role in maintaining epidermal homeostasis by controlling the Ca 2+ gradient.

  6. Extracellular Matrix as a Regulator of Epidermal Stem Cell Fate.

    Science.gov (United States)

    Chermnykh, Elina; Kalabusheva, Ekaterina; Vorotelyak, Ekaterina

    2018-03-27

    Epidermal stem cells reside within the specific anatomic location, called niche, which is a microenvironment that interacts with stem cells to regulate their fate. Regulation of many important processes, including maintenance of stem cell quiescence, self-renewal, and homeostasis, as well as the regulation of division and differentiation, are common functions of the stem cell niche. As it was shown in multiple studies, extracellular matrix (ECM) contributes a lot to stem cell niches in various tissues, including that of skin. In epidermis, ECM is represented, primarily, by a highly specialized ECM structure, basement membrane (BM), which separates the epidermal and dermal compartments. Epidermal stem cells contact with BM, but when they lose the contact and migrate to the overlying layers, they undergo terminal differentiation. When considering all of these factors, ECM is of fundamental importance in regulating epidermal stem cells maintenance, proper mobilization, and differentiation. Here, we summarize the remarkable progress that has recently been made in the research of ECM role in regulating epidermal stem cell fate, paying special attention to the hair follicle stem cell niche. We show that the destruction of ECM components impairs epidermal stem cell morphogenesis and homeostasis. A deep understanding of ECM molecular structure as well as the development of in vitro system for stem cell maintaining by ECM proteins may bring us to developing new approaches for regenerative medicine.

  7. Epidermal growth factor and insulin-like growth factor I upregulate the expression of the epidermal growth factor system in rat liver

    DEFF Research Database (Denmark)

    Bor, M V; Sørensen, B S; Vinter-Jensen, L

    2000-01-01

    BACKGROUND/AIM: Both epidermal growth factor and insulin-like growth factor I play a role in connection with the liver. In the present study, the possible interaction of these two growth factor systems was studied by investigating the effect of epidermal growth factor or insulin-like growth factor...... I treatment on the expression of the epidermal growth factor receptor, and its activating ligands, transforming growth factor-alpha and epidermal growth factor. METHODS: Fifty-five male rats received no treatment, human recombinant epidermal growth factor or human recombinant insulin-like growth.......8+/-1.6 fmol/mg protein epidermal growth factor and 144+/-22 fmol/mg protein transforming growth factor-alpha. Both epidermal growth factor and insulin-like growth factor I treatment increased the expression of mRNA for transforming growth factor-alpha and epidermal growth factor receptor, as well...

  8. Selection of DNA aptamers against epidermal growth factor receptor with high affinity and specificity.

    Science.gov (United States)

    Wang, Deng-Liang; Song, Yan-Ling; Zhu, Zhi; Li, Xi-Lan; Zou, Yuan; Yang, Hai-Tao; Wang, Jiang-Jie; Yao, Pei-Sen; Pan, Ru-Jun; Yang, Chaoyong James; Kang, De-Zhi

    2014-10-31

    Epidermal growth factor receptor (EGFR/HER1/c-ErbB1), is overexpressed in many solid cancers, such as epidermoid carcinomas, malignant gliomas, etc. EGFR plays roles in proliferation, invasion, angiogenesis and metastasis of malignant cancer cells and is the ideal antigen for clinical applications in cancer detection, imaging and therapy. Aptamers, the output of the systematic evolution of ligands by exponential enrichment (SELEX), are DNA/RNA oligonucleotides which can bind protein and other substances with specificity. RNA aptamers are undesirable due to their instability and high cost of production. Conversely, DNA aptamers have aroused researcher's attention because they are easily synthesized, stable, selective, have high binding affinity and are cost-effective to produce. In this study, we have successfully identified DNA aptamers with high binding affinity and selectivity to EGFR. The aptamer named TuTu22 with Kd 56±7.3nM was chosen from the identified DNA aptamers for further study. Flow cytometry analysis results indicated that the TuTu22 aptamer was able to specifically recognize a variety of cancer cells expressing EGFR but did not bind to the EGFR-negative cells. With all of the aforementioned advantages, the DNA aptamers reported here against cancer biomarker EGFR will facilitate the development of novel targeted cancer detection, imaging and therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Human recombinant interleukin-1 beta- and tumor necrosis factor alpha-mediated suppression of heparin-like compounds on cultured porcine aortic endothelial cells

    International Nuclear Information System (INIS)

    Kobayashi, M.; Shimada, K.; Ozawa, T.

    1990-01-01

    Cytokines are known to tip the balance of the coagulant-anticoagulant molecules on the endothelial cell surface toward intravascular coagulation. Their effects on endothelial cell surface-associated heparin-like compounds have not been examined yet. Incorporation of [35S]sulfate into heparan sulfate on cultured porcine aortic endothelial cells was suppressed by human recombinant interleukin-1 beta (rIL-1 beta) or tumor necrosis factor alpha (rTNF alpha) in a dose- and time-dependent manner with little effect on cell number, protein content, and [3H]leucine incorporation of cells. Maximal inhibition was achieved by incubation of cells with 100 ng/ml of rIL-1 beta or 5 ng/ml of rTNF alpha for 12-24 hours, resulting in a reduction of the synthesis of heparan sulfate on the cell surface by approximately 50%. The dose dependency was consistent with that seen in the stimulation of endothelial cell procoagulant activity by each cytokine. The suppression of heparan sulfate synthesis was sustained for at least 48 hours after pretreatment of cells with cytokines and was unchanged after the addition of indomethacin or polymyxin B. The rate of degradation of prelabeled 35S-heparan sulfate on the cell surface was not altered by cytokine treatments. Neither the size, the net negative charge, nor the proportion of the molecule with high affinity for antithrombin III of endothelial cell heparan sulfate was changed by cytokines. Furthermore, specific binding of 125I-labeled antithrombin III to the endothelial cell surface was reduced to 40-60% of control by cytokines. In parallel with reduction in binding, antithrombin III cofactor activity was partially diminished in cytokine-treated endothelial cells. Thus, cytokine-mediated suppression of heparin-like substance on endothelial cells appears to be another cytokine-inducible endothelial effects affecting coagulation

  10. Blood interaction with a Bioline heparin coated HIA-VAD : A study on calves

    NARCIS (Netherlands)

    vanderKamp, KWHJ; Magielse, CPE; Elstrodt, JM; vanderMeer, J; vanOeveren, W; Rakhorst, G

    The blood compatibility of ventricular assist devices developed by the Helmholtz institute Aachen (HA-VAD's) was tested on calves. Seven calves received a non-coated HIA-VAD (control) and three a Bioline heparin coated device. The circulatory support of these HIA-VAD's lasted one week. Mechanical

  11. Cooperative control of blood compatibility and re-endothelialization by immobilized heparin and substrate topography.

    Science.gov (United States)

    Ding, Yonghui; Yang, Meng; Yang, Zhilu; Luo, Rifang; Lu, Xiong; Huang, Nan; Huang, Pingbo; Leng, Yang

    2015-03-01

    A wide variety of environmental cues provided by the extracellular matrix, including biophysical and biochemical cues, are responsible for vascular cell behavior and function. In particular, substrate topography and surface chemistry have been shown to regulate blood and vascular compatibility individually. The combined impact of chemical and topographic cues on blood and vascular compatibility, and the interplay between these two types of cues, are subjects that are currently being explored. In the present study, a facile polydopamine-mediated approach is introduced for immobilization of heparin on topographically patterned substrates, and the combined effects of these cues on blood compatibility and re-endothelialization are systematically investigated. The results show that immobilized heparin and substrate topography cooperatively modulate anti-coagulation activity, endothelial cell (EC) attachment, proliferation, focal adhesion formation and endothelial marker expression. Meanwhile, the substrate topography is the primary determinant of cell alignment and elongation, driving in vivo-like endothelial organization. Importantly, combining immobilized heparin with substrate topography empowers substantially greater competitive ability of ECs over smooth muscle cells than each cue individually. Moreover, a model is proposed to elucidate the cooperative interplay between immobilized heparin and substrate topography in regulating cell behavior. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Low-molecular-weight heparin in the treatment of patients with venous thromboembolism

    NARCIS (Netherlands)

    tenCate, JW; Buller, HR; Gent, M; Hirsh, J; Prins, MH; Baildon, R; Lensing, AWA; Anderson, DR; vanBeek, EJR; Fiesinger, JN; Tijssen, JGP; vanBarneveld, A; Eimers, LT; Graafsma, YP; Hettiarachchi, R; Hutten, B; Redekop, K; Haley, S; LIberale, L; Finch, T; Whittaker, S; Wilkinson, L; Prandoni, P; Villalta, S; Girolami, B; Bagatella, P; Rossi, L; Girolami, A; Piovella, F; Barone, M; Beltrametti, C; Serafini, S; Siragusa, S; Ascari, E; Kovacs, MJ; Morrow, B; Kovacs, J; Kuijer, PMM; Koopman, MMW; Jagt, H; Weitz, J; Kearon, C; Biagioni, L; Haas, S; Lossner, F; Spengel, FA; Berger, M; Demers, C; Poulin, J; vanderMeer, J; Que, GTH; Smid, WM; Robinson, KS; Boyle, E; Leclerc, [No Value; StJacques, B; Finkenbine, S; Gallus, AS; Cohlan, D; Rich, C; Brandjes, DPM; Hoefnagel, CA; deRijk, M; Turkstra, F; Desjardins, L; CoteDesjardins, J; Couture, L; Ruel, M; Villenueve, J; Geerts, WH; Jay, RM; Code, EKI; Turpie, AGG; Johnson, J; Nguyen, P; Cusson, [No Value; Roy, S; Wells, PS; Bormanis, J; Goudie, D; Cruickshank, M; vonLewinski, M; Monreal, M; Sahuquillo, JC; Lafoz, E; Simonneau, G; Parent, F; Jagot, J; Douketis, JD; Kinnon, K; Ginsberg, JS; BrillEdwards, P; Donovan, D; Ockelford, PA; Kassis, J; Bornais, S; Planchon, B; ElKouri, D; Pistorius, MA; Escribano, M; Garrido, G; Chesterman, CN; Chong, BH; Pritchard, S; Cade, JF; Bynon, T; Stanford, J; Brien, WM; Palmer, B; Faivre, R; Petiteau, B; Manucci, PM; Moia, M; Bucciarelli, P

    1997-01-01

    Background Low-molecular-weight heparin is known to be safe and effective for the initial Treatment of patients with proximal deep-vein thrombosis. However, its application to patients with pulmonary embolism or previous episodes of thromboembolism has not been studied. Methods We randomly assigned

  13. Improved distribution and reduced toxicity of adriamycin bound to albumin-heparin microspheres

    NARCIS (Netherlands)

    Cremers, Harry; Cremers, H.F.M.; Bayon, L.G.; Verrijk, R.; Wesseling, M.M.; Wondergem, J.; Heuff, G.; Kwon, G.S.; Bae, Y.H.; Feijen, Jan; Kim, S.W.

    1995-01-01

    Adriamycin (ADR) was formulated in albumin-heparin conjugate microspheres (AHCMS) to improve site-specific delivery and to reduce the toxicity of the drug. The effect of formulating ADR in AHCMS was investigated upon intrahepatic administration to male Wag/Rij rats. After intraveno-portal (i.v.p.)

  14. Transfer of heparin polyion across a polarized water/ionic liquid membrane interface

    Czech Academy of Sciences Publication Activity Database

    Langmaier, Jan; Samec, Zdeněk; Samcová, E.; Tůma, P.

    2012-01-01

    Roč. 24, OCT 2012 (2012), s. 25-27 ISSN 1388-2481 R&D Projects: GA ČR GAP206/11/0707 Institutional support: RVO:61388955 Keywords : heparin polyion * ionic liquid membrane * amperometric detection Subject RIV: CG - Electrochemistry Impact factor: 4.425, year: 2012

  15. Immobilization of heparin to EDC/NHS-crosslinked collagen. Characterization and in vitro evaluation

    NARCIS (Netherlands)

    Wissink, M.J.B.; Beernink, R.; Pieper, J.S.; Poot, Andreas A.; Engbers, G.H.M.; Beugeling, T.; Beugeling, T.; van Aken, W.G.; Feijen, Jan

    2001-01-01

    In the present study, heparin immobilization to a non-cytotoxic crosslinked collagen substrate for endothelial cell seeding was investigated. Crosslinking of collagen using N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide (EDC) and N-hydroxysuccinimide (NHS) resulted in a material containing 14 free

  16. Effect of low-dose heparin on urinary albumin excretion in insulin-dependent diabetes mellitus

    DEFF Research Database (Denmark)

    Myrup, B; Hansen, P M; Jensen, T

    1995-01-01

    We investigated the effect of heparin on urinary albumin excretion in patients with insulin-dependent diabetes mellitus. 39 patients with persistent urinary albumin excretion of 30-300 mg/24 h were randomly treated for 3 months with subcutaneous injections twice daily of isotonic saline, 5000 IU...

  17. Amperometric Sensor for Heparin: Sensing Mechanism and Application in Human Blood Plasma Analysis

    Czech Academy of Sciences Publication Activity Database

    Langmaier, Jan; Olšák, J.; Samcová, E.; Samec, Zdeněk; Trojánek, Antonín

    2006-01-01

    Roč. 18, 13-14 (2006), s. 1329-1338 ISSN 1040-0397 R&D Projects: GA ČR GA203/04/0424 Institutional research plan: CEZ:AV0Z40400503 Keywords : heparin * amperometry * PVC membrane electrode * sensing mechanism * human blood plasma Subject RIV: CG - Electrochemistry Impact factor: 2.444, year: 2006

  18. Early Heparin Administration Reduces Risk for Left Atrial Thrombus Formation during Atrial Fibrillation Ablation Procedures

    Directory of Open Access Journals (Sweden)

    Stefan Asbach

    2011-01-01

    Full Text Available Objective. Despite the use of anticoagulation during left atrial (LA ablation procedures, ischemic cerebrovascular accidents (CVAs are recognized as a serious complication. Heparin is usually given after safe transseptal access has been obtained, resulting in a short unprotected dwell time of catheters within the LA, which may account for CVAs. We investigated the frequency of CVAs and LA thrombus formation as detected by intracardiac ultrasound (ICE depending on the timing of heparin administration. Methods and Results. Sixty LA ablation procedures with the use of ICE were performed in 55 patients. Patients were grouped by heparin administration after (Group I, =13 and before (Group II, =47 transseptal access. Group I patients were younger (56.6±13.7 versus 65.9±9.9 years, =.01; other clinical and echocardiographic characteristics did not differ between groups. Early thrombus formation was observed in 2 (15.4% of group I patients as compared to 0% of group II patients (=.04. One CVA (2.1% occurred in one group II patient without prior thrombus detection, and none occurred in group I patients (=ns. Conclusion. Early administration of heparin reduces the risk of early intracardiac thrombus formation during LA ablation procedures. This did not result in reduced rate of CVAs.

  19. Extrapulmonary colony formation after intravenous injection of tumour cells into heparin treated animals

    NARCIS (Netherlands)

    Maat, B.

    1978-01-01

    Recent data on extrapulmonary colony formation after heparin administration are inconclusive. A systemic study of this topic was undertaken with 4 experimental tumour systems and 2 distinct periods of reduced clotting capacity in rats and mice. I.v. injection of various numbers of tumour cells into

  20. Influence of heparin on the assay of amitriptyline, clomipramine, and their metabolites

    NARCIS (Netherlands)

    Levering, S.C.M.; Oostelbos, M.C.J.M.; Toll, P.J.M.M.; Loonen, A.J.M.

    1996-01-01

    In this study the effect of the use of lithium heparin containers on the plasma levels of amitriptyline, clomipramine, and their metabolites was investigated. Twenty-five patients (10 men and 15 women, mean age 51.8 ± 14.9 years) taking either amitriptyline or clomipramine in a daily dosage varying

  1. Biosynthesis of heparin. Effects of n-butyrate on cultured mast cells

    International Nuclear Information System (INIS)

    Jacobsson, K.G.; Riesenfeld, J.; Lindahl, U.

    1985-01-01

    Murine mastocytoma cells were incubated in vitro with inorganic [ 35 S]sulfate, in the absence or presence of 2.5 mM n-butyrate, and labeled heparin was isolated. The polysaccharide produced in the presence of butyrate showed a lower charge density on anion exchange chromatography than did the control material and a 3-fold increased proportion of components with high affinity for antithrombin. Structural analysis of heparin labeled with [ 3 H] glucosamine in the presence of butyrate showed that approximately 35% of the glucosamine units were N-acetylated, as compared to approximately 10% in the control material; the nonacetylated glucosamine residues were N-sulfated. The presence of butyrate thus leads to an inhibition of the N-deacetylation/N-sulfation process in heparin biosynthesis, along with an augmented formation of molecules with high affinity for antithrombin. Preincubation of the mastocytoma cells with butyrate was required for manifestation of either effect; when the preincubation period was reduced from 24 to 10 h the effects of butyrate were no longer observed. A polysaccharide formed on incubating mastocytoma microsomal fraction with UDP-[ 3 H]glucuronic acid, UDP-N-acetylglucosamine, and 3'-phosphoadenylylsulfate in the presence of 5 mM butyrate showed the same N-acetyl/N-sulfate ratio as did the corresponding control polysaccharide, produced in the absence of butyrate. These findings suggest that the effect of butyrate on heparin biosynthesis depends on the integrity of the cell

  2. Synthesis and characterization of polystyrene-poly(ethylene oxide)-heparin block copolymers

    NARCIS (Netherlands)

    Vulić, I.; Okano, T.; Kim, S.W.; Feijen, Jan

    1988-01-01

    A procedure for the preparation of new block copolymers composed of a hydrophobic block of polystyrene, a hydrophilic spacer-block of poly(ethylene oxide) and a bioactive block of heparin was investigated. Polystyrene with one amino group per chain was synthesized by free radical oligomerization of

  3. Improved synthesis of polystyrene-poly(ethylene oxide)-heparin block copolymers

    NARCIS (Netherlands)

    Vulic, I.; Loman, A.J.B.; Feijen, Jan; Okano, T.; Kim, S.W.

    1990-01-01

    A novel procedure for the synthesis of block copolymers composed of a hydrophobic block of polystyrene, a hydrophilic block of poly(ethylene oxide) and a bioactive block of nitrous acid-degraded heparin was developed. Amino-semitelechelic polystyrene was prepared by anionic polymerization of styrene

  4. Heparin interferes with the radioenzymatic and homogeneous enzyme immunoassays for aminoglycosides

    International Nuclear Information System (INIS)

    Krogstad, D.J.; Granich, G.G.; Murray, P.R.; Pfaller, M.A.; Valdes, R.

    1981-01-01

    Heparin interferes with measurement of aminoglycosides in serum by biological, radioenzymatic, and homogeneous enzyme immunoassay techniques, but not with radioimmunoassay. At concentrations greater than or equal to 10 5 and greater than or equal to 3 X 10 6 USP units/L, respectively, it interferes with the radioenzymatic assay by inhibiting the gentamicin 3-acetyltransferase and kanamycin 6'-acetyltransferase enzymes used in the assay. It interferes with the homogeneous enzyme immunoassays for gentamicin and tobramycin (at concentrations greater than or equal to 10 5 and greater than or equal to10 4 USP units/L, respectively), but not with the commercially available homogeneous enzyme immunoassays for other drugs. Heparin interference with the homogeneous enzyme immunoassay for aminoglycosides requires both the heparin polyanion and glucose-6-phosphate dehydrogenase bound to a cationic aminoglycoside. This interference can be reproduced with dextran sulfate (but not dextran), and does not occur with free enzyme (glucose-6-phosphate dehydrogenase) alone. Heparin interference with these two assays and at concentrations that may be present in intravenous infusions or in seriously underfilled blood-collection tubes is described

  5. In vitro Heparin Precipitation in the Plasma of Euthyroid women with ...

    African Journals Online (AJOL)

    OBJECTIVE: Women with elevated Lp(a), who are susceptible to atherosclerosis, get to reduce, their cardiovascular disease by in-vivo administration of low dose heparin. And history of recurrent miscarriage associated with auto antibodies have had a high rate of life births in subsequent pregnancies when they were ...

  6. Ergotism of the lower limb complicating DHE-heparin thrombosis prophylaxis. Observation by serial angiography

    Energy Technology Data Exchange (ETDEWEB)

    Warmuth-Metz, M.

    1988-10-01

    Today ergotism is becoming more and more important as a complication in the treatment of migraine headache or thrombosis prophylaxis with DHE heparin. Although complete recovery is seldom reported in the current literature, in our case it was possible to resolve a spasm of the left lower limb completely by early diagnosis and adaequate pharmacological treatment. The case was well documented by serial angiography.

  7. Endothelial glycocalyx degradation induces endogenous heparinization in patients with severe injury and early traumatic coagulopathy

    DEFF Research Database (Denmark)

    Ostrowski, Sisse R; Johansson, Pär I

    2012-01-01

    There is emerging evidence that early trauma-induced coagulopathy (TIC) is mechanistically linked to disruption of the vascular endothelium and its glycocalyx, assessed by thrombomodulin and syndecan 1, respectively. This study evaluated if degradation of the endothelial glycocalyx and ensuing...... release of its heparin-like substances induce autoheparinization and thereby contributes to TIC....

  8. Low dose intravesical heparin as prophylaxis against recurrent noninvasive (stage Ta) bladder cancer

    DEFF Research Database (Denmark)

    Bitsch, M; Hermann, G G; Andersen, J P

    1990-01-01

    A controlled randomized clinical trial was conducted to examine the efficacy of topical low dose heparin (0.125 gm./l., 25,000 units per l.) as prophylaxis against recurrent noninvasive (stage Ta) transitional cell bladder cancer. Transurethral tumor resection was done with irrigation fluid conta...

  9. Optical sensing of sulfate by polymethinium salt receptors: colorimetric sensor for heparin

    Czech Academy of Sciences Publication Activity Database

    Bříza, T.; Kejík, Z.; Císařová, I.; Králová, Jarmila; Martásek, P.; Král, V.

    2008-01-01

    Roč. 16, - (2008), s. 1901-1903 ISSN 1359-7345 R&D Projects: GA AV ČR KAN200200651; GA ČR(CZ) GA203/06/1038 Institutional research plan: CEZ:AV0Z50520514 Keywords : colorimetric sensor * heparin * polymethinium salt Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.340, year: 2008

  10. Venous thromboembolism in pregnancy: prophylaxis and treatment with low molecular weight heparin

    DEFF Research Database (Denmark)

    Andersen, Anita Sylvest; Berthelsen, Jørgen G; Bergholt, Thomas

    2010-01-01

    OBJECTIVE: To evaluate the safety of individually dosed low molecular weight heparin (LMWH) for prophylaxis and treatment of thromboembolic complications in pregnancy. DESIGN: Cohort study with a chronologic register-based control group. SETTING: Department of Obstetrics and Gynecology, Hillerød ...

  11. Venous thromboembolism in pregnancy: prophylaxis and treatment with low molecular weight heparin

    DEFF Research Database (Denmark)

    Andersen, Anita Sylvest; Berthelsen, Jørgen G.; Bergholt, Thomas

    2010-01-01

    OBJECTIVE: To evaluate the safety of individually dosed low molecular weight heparin (LMWH) for prophylaxis and treatment of thromboembolic complications in pregnancy. DESIGN: Cohort study with a chronologic register-based control group. SETTING: Department of Obstetrics and Gynecology, Hillerød...

  12. The impact of heparin-coated circuits on hemodynamics during and after cardiopulmonary bypass

    NARCIS (Netherlands)

    de Vroege, R; Huybregts, R; van Oeveren, W; van Klarenbosch, J; Linley, G; Mutlu, J; Jansen, E; Hack, E; Eijsman, L; Wildevuur, C

    This study was performed to investigate if heparin-coated extracorporeal circuits can reduce the systemic inflammatory reaction with the subsequent release of vasoactive substances during and after cardiopulmonary bypass. Fifty-one patients scheduled for coronary artery bypass grafting were perfused

  13. ADRIAMYCIN-LOADED ALBUMIN-HEPARIN CONJUGATE MICROSPHERES FOR INTRAPERITONEAL CHEMOTHERAPY

    NARCIS (Netherlands)

    CREMERS, HFM; SEYMOUR, LW; LAM, K; LOS, G; KWON, G; BAE, YH; KIM, SW; FEIJEN, J

    1994-01-01

    Adriamycin-loaded albumin-heparin conjugate microspheres (ADR-AHCMS) were evaluated as possible intraperitoneal (i.p.) delivery systems for site-specific cytotoxic action. The biocompatibility of the microspheres after intraperitoneal injection was tested first. 1 day after i.p. administration of

  14. Release of proteins via ion exchange from albumin-heparin microspheres

    NARCIS (Netherlands)

    Kwon, Glen S.; Bae, You Han; Cremers, H.F.M.; Cremers, Harry; Feijen, Jan; Kim, Sung Wan

    1992-01-01

    Albumin-heparin and albumin microspheres were prepared as ion exchange gels for the controlled release of positively charged polypeptides and proteins. The adsorption isotherms of chicken egg and human lysozyme, as model proteins, on microspheres were obtained. An adsorption isotherm of chicken egg

  15. Effect of low-dose heparin on urinary albumin excretion in insulin-dependent diabetes mellitus

    NARCIS (Netherlands)

    Myrup, B.; Hansen, P.M.; Jensen, T.; Kofoed-Enevoldsen, A.; Feldt-Rasmussen, B.; Gram, J.; Kluft, C.; Jespersen, J.; Deckert, T.

    1995-01-01

    We investigated the effect of heparin on urinary albumin excretion in patients with insulin-dependent diabetes mellitus. 39 patients with persistent urinary albumin excretion of 30-300 mg/24 h were randomly treated for 3 months with subcutaneous injections twice daily of isotonic saline, 5000 IU

  16. Epidermal growth factor and growth in vivo

    International Nuclear Information System (INIS)

    Rhodes, J.A.

    1986-01-01

    Epidermal growth factor (EGF) causes a dose-dependent thickening of the epidermis in suckling mice. The cellular mechanisms underlying this thickening were analyzed by measuring the effect of EGF on the cell-cycle. Neonatal mice were given daily injections of either 2ug EGF/g body weight/day or an equivalent volume of saline, and on the seventh day received a single injection of 3 H-thymidine. At various times the mice were perfused with fixative; 1um sections of skin were stained with a modification of Harris' hematoxylin and were autoradiographed. The sections were analyzed using three methods based on the dependence on time after injection of 3 H-thymidine of: frequency of labelled mitoses, labelling index, and reciprocal grains/nucleus. It was found that EGF caused a two-fold increase in the cell production rate. The effect of exogenous EGF on the morphology of gastric mucosa and incisors of suckling mice was also studied. The gastric mucosa appeared thicker in EGF-treated animals, but the effect was not statistically significant. In contrast to its effect on epidermis and gastric mucosa, EGF caused a significant, dose-dependent decrease in the size of the incisors. Because the mouse submandibular salivary gland is the major source of EGF the effect of sialoadenectomy on female reproductive functions was examined. Ablation of the submandibular gland had no effect on: length of estrus cycle, ability of the female to produce litters, length of the gestation period, litter size, and weight of the litter at birth. There was also no effect on survival of the offspring or on age at which the eyelids separated

  17. Surface Modification of Titanium with BMP-2/GDF-5 by a Heparin Linker and Its Efficacy as a Dental Implant

    Directory of Open Access Journals (Sweden)

    Dae Hyeok Yang

    2017-01-01

    Full Text Available In this study, we prepared human bone morphogenetic protein-2 (hBMP-2/human growth and differentiation factor-5 (hGDF-5-coated titanium (Ti disc and screw types for controlled release of the growth factors (GFs. The two growth factors were coated onto Ti with a smooth surface using their specific interaction with heparin, because they have heparin binding sites in their molecular structures. Efficacy of the two growth factor-coated Ti for enhancement of bone formation and osseointegration was compared to pristine Ti, and hBMP-2- and hGDF-5-coated Ti in vivo. The surface chemical composition, surface morphology, and wettability characteristics of the metal samples were determined by X-ray photoelectron spectroscopy (XPS, scanning electron microscopy (SEM, and contact angle measurement, respectively. The initial burst of hBMP-2, hGDF-5, and their combination, occurred within one day of the release study, resulting in 12.5%, 4.5%, and 13.5%/3.2%, and then there was a sustained, even release of these two growth factors from the coated metal for 30 days. In vitro tests revealed that MC3T3-E1 cells cultured on the two growth factor-coated Ti had a higher proliferation rate and a higher activity for alkaline phosphatase (ALP, which led to a larger amount of calcium deposition and larger expressions of type I collagen (COL 1, ALP, and osteocalcin (OCN mRNAs. In vivo animal tests using ten white New Zealand rabbits showed that the two growth factor-coated Ti enhanced bone formation and osseointegration at the interface between the implants and host bone. In addition, histological evaluation showed that bone remodeling, including bone formation by osteoblasts and bone resorption by osteoclasts, actively occurred between the two growth factor-coated Ti and host bone. Consequently, it is suggested that Ti surface modification with the combination of hBMP-2 and hGDF-5 for the two growth factor-coated Ti implants can improve the clinical properties of

  18. Heparin for prolonging peripheral intravenous catheter use in neonates: a randomized controlled trial.

    Science.gov (United States)

    Upadhyay, A; Verma, K K; Lal, P; Chawla, D; Sreenivas, V

    2015-04-01

    To determine the efficacy of heparinized saline administered as intermittent flush on functional duration of the peripheral intravenous catheter (PIVC) in neonates. Randomized, double-blind and placebo-controlled trial. Neonatal intensive care unit of a teaching hospital. Term and preterm neonates born at >32 weeks of gestation who required PIVC only for intermittent administration of antibiotics. Eligible neonates were randomized to receive 1 ml of either heparinized saline (10 U ml(-1)) (n=60) or normal saline (n=60) every 12 h before and after intravenous antibiotics. Functional duration of first peripheral intravenous catheter. A total of 120 neonates were randomized to two groups of 60 neonates each. The mean (s.d.) of age of babies in case and control group was 5.7 (2.5) days and 4.6 (3.1) days, respectively. The average weight of babies in both the groups was 2.1 kg. Mean functional duration of first catheter was more in heparinized saline group, mean (s.d.) of 71.68 h  (27.3) as compared with 57.7 h (23.6) in normal saline group (P<0.005). The mean (95% confidence interval) difference in functional duration in the two groups was 13.9 h (4.7-23.15). Mean duration of patency for any catheter was also significantly more in heparinized saline group than control group. Heparinized saline flush increases the functional duration of peripheral intravenous catheter.

  19. Epidermal growth factor reactivity in rat milk

    DEFF Research Database (Denmark)

    Raaberg, Lasse; Nexø, Ebba; Tollund, L

    1990-01-01

    whey elutes as a broad peak corresponding to a Stokes radius of 4.0 nm (an approximate molecular weight of 80 kDa). Almost no 6 kDa EGF is present. Judged by gel filtration of whey pre-incubated with 125I-EGF (6 kDa), no binding protein for EGF is present in rat whey. When rat milk is incubated...

  20. 111In-labeled platelets: effects of heparin on uptake by venous thrombi and relationship to the activated partial thromboplastin time

    International Nuclear Information System (INIS)

    Fedullo, P.F.; Moser, K.M.; Moser, K.S.; Konopka, R.; Hartman, M.T.

    1982-01-01

    The goal of heparin therapy in deep vein thrombosis is to prevent thrombus extension. The relationship between thrombus extension and the results of coagulation tests used to monitor heparin therapy is unclear. To explore this relationship, we studied the effect of several heparin regimens on the accretion of 111 In-labeled platelets on fresh venous thrombi, as detected by gamma imaging, and monitored the activated partial thromboplastin time (APTT). Six dogs were treated with a 300-U/kg bolus of heparin followed by a 90-U/kg/hour heparin infusion, a dose of heparin sufficient to increase the APTT to levels greater than eight times baseline (APTT ratio); platelet accretion (thrombus imaging) occurred only after the heparin effect was reversed with protamine sulfate. Nineteen dogs were treated with a 150-U/kg bolus of heparin followed by a 4-hour, 45-U/kg/hour heparin infusion; a thrombus was demonstrated only after protamine injection in 12 (mean APTT ratio 1.3 +/- 0.19) and before protamine injection in seven. In thirteen of these 19 dogs, 30 minutes separated the platelet injection from heparin therapy, while in six this duration was less than 30 minutes. In four of these six dogs, thrombi were demonstrated before protamine therapy and at APTT ratios greater than 3.0. Finally, 10 dogs were treated with a 100-U/kg bolus followed by a 3-hour, 50-U/kg/hour heparin infusion, after which the APTT was allowed to return to baseline values spontaneously. In all 10 dogs, a thrombus was demonstrated only after cessation of the heparin infusion, and at a mean APTT ratio of 1.4 +/- 0.15 times baseline. These results suggest that, except with very early platelet injection, platelet accretion by thrombi is consistently inhibited by heparin at APTT ratios greater than 2.5. Platelet accretion by venous thrombi occurs within narrow limits of heparin effect as reflected by the APTT

  1. Subtle differences in commercial heparins can have serious consequences for cardiopulmonary bypass patients: A randomized controlled trial.

    Science.gov (United States)

    Arsenault, Kyle A; Paikin, Jeremy S; Hirsh, Jack; Dale, Brian; Whitlock, Richard P; Teoh, Kevin; Young, Ed; Ginsberg, Jeffrey S; Weitz, Jeffrey I; Eikelboom, John W

    2012-10-01

    To compare the potency, reversibility, and perioperative bleeding risk of Hepalean with those of PPC heparin. Because in vitro testing failed to detect differences in the potency or protamine reversibility of the 2 heparin preparations, we conducted a parallel group, single-center, double-blind, randomized, controlled trial to compare the anticoagulant effects of Hepalean to those of PPC heparin in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass. From June 1, 2011, to June 30, 2011, we randomly assigned 11 patients to receive PPC heparin and 10 to receive Hepalean. Despite similar initial doses of heparin, the median initial activated clotting time was numerically lower in the PPC heparin group than in the Hepalean group (median, 516.0 seconds; interquartile range, 481.0-633.0; vs median, 584.0 seconds, interquartile range, 520.0-629.0; P = .418). Those given PPC heparin required a greater total heparin dose (median, 46,000.0 U; interquartile range, 39,500.0-60,000.0 vs median, 34,500.0 U; interquartile range, 32,250.0-37,000.0; P = .011) and a greater dose of heparin per kilogram than those given Hepalean (median, 572.9 U/kg; interquartile range, 443.0-659.7 vs median, 401.1 U/kg; interquartile range, 400.0-419.4; P = .003). The key secondary results included an increased median total protamine dose (median, 600.0 mg; interquartile range, 550.0-700.0; vs median, 500.0 mg; interquartile range, 425.0-542.5; P = .026) and a trend toward increased chest tube output within 24 hours (median, 830.0 mL; interquartile range, 425.0-1135.0; vs median, 702.5 mL; interquartile range, 550.0-742.5; P = .324). PPC heparin use was associated with greater heparin and protamine dose requirements than Hepalean. These findings indicate that heparin preparations are not interchangeable and suggest that a direct comparison of the potency with the brand in use is needed if a change is made to ensure that the agents exert similar anticoagulant

  2. Oral mucosa: an alternative epidermic cell source to develop autologous dermal-epidermal substitutes from diabetic subjects

    Directory of Open Access Journals (Sweden)

    Daniela GUZMÁN-URIBE

    Full Text Available Abstract Oral mucosa has been highlighted as a suitable source of epidermal cells due to its intrinsic characteristics such as its higher proliferation rate and its obtainability. Diabetic ulcers have a worldwide prevalence that is variable (1%-11%, meanwhile treatment of this has been proven ineffective. Tissue-engineered skin plays an important role in wound care focusing on strategies such autologous dermal-epidermal substitutes. Objective The aim of this study was to obtain autologous dermal-epidermal skin substitutes from oral mucosa from diabetic subjects as a first step towards a possible clinical application for cases of diabetic foot. Material and Methods Oral mucosa was obtained from diabetic and healthy subjects (n=20 per group. Epidermal cells were isolated and cultured using autologous fibrin to develop dermal-epidermal in vitro substitutes by the air-liquid technique with autologous human serum as a supplement media. Substitutes were immunocharacterized with collagen IV and cytokeratin 5-14 as specific markers. A Student´s t- test was performed to assess the differences between both groups. Results It was possible to isolate epidermal cells from the oral mucosa of diabetic and healthy subjects and develop autologous dermal-epidermal skin substitutes using autologous serum as a supplement. Differences in the expression of specific markers were observed and the cytokeratin 5-14 expression was lower in the diabetic substitutes, and the collagen IV expression was higher in the diabetic substitutes when compared with the healthy group, showing a significant difference. Conclusion Cells from oral mucosa could be an alternative and less invasive source for skin substitutes and wound healing. A difference in collagen production of diabetic cells suggests diabetic substitutes could improve diabetic wound healing. More research is needed to determine the crosstalk between components of these skin substitutes and damaged tissues.

  3. Immune sensitization against epidermal antigens in polymorphous light eruption

    International Nuclear Information System (INIS)

    Gonzalez-Amaro, R.; Baranda, L.; Salazar-Gonzalez, J.F.; Abud-Mendoza, C.; Moncada, B.

    1991-01-01

    To get further insight into the pathogenesis of polymorphous light eruption, we studied nine patients with polymorphous light eruption and six healthy persons. Two skin biopsy specimens were obtained from each person, one from previously ultraviolet light-irradiated skin and another one from unirradiated skin. An epidermal cell suspension, skin homogenate, or both were prepared from each specimen. Autologous cultures were made with peripheral blood mononuclear cells combined with irradiated or unirradiated skin homogenate and peripheral blood mononuclear cells combined with irradiated or unirradiated epidermal cell suspension. Cell proliferation was assessed by 3H-thymidine incorporation assay. The response of peripheral blood mononuclear cells to unirradiated epidermal cells or unirradiated skin homogenate was similar in both patients and controls. However, peripheral blood mononuclear cells from patients with polymorphous light eruption showed a significantly increased proliferative response to both irradiated epidermal cells and irradiated skin homogenate. Our results indicate that ultraviolet light increases the stimulatory capability of polymorphous light eruption epidermal cells in a unidirectional mixed culture with autologous peripheral blood mononuclear cells. This suggests that an immune sensitization against autologous ultraviolet light-modified skin antigens occurs in polymorphous light eruption

  4. Radiotherapy and receptor of epidermal growth factor

    International Nuclear Information System (INIS)

    Deberne, M.

    2009-01-01

    The expression level of the receptor of the epidermal growth factor is in correlation with the tumor cells radiosensitivity. An overexpression of the E.G.F.R. is often present in the bronchi cancer, epidermoid carcinomas of the O.R.L. sphere, esophagus, uterine cervix, and anal duct but also in the rectum cancers and glioblastomas. At the clinical level, the E.G.F.R. expression is in correlation with an unfavourable prognosis after radiotherapy in numerous tumoral localizations. In the rectum cancers it is an independent prognosis factor found in multifactorial analysis: increase of the rate of nodes and local recurrence when the E.G.F.R. is over expressed. In the uterine cervix cancers, the survival is is negatively affected in multifactorial analysis by the E.G.F.R. membranes expression level. At the therapy level, the development of anti E.G.F.R. targeted therapies (tyrosine kinase inhibitors and monoclonal antibodies) opens a new therapy field at radio-sensitivity potentiality. The irradiation makes an activation of the E.G.F.R. way that would be partially responsible of the post irradiation tumoral repopulation. This activation leads the phosphorylation of the PI3 kinase ways and M.A.P. kinase ones, then the Akt protein one that acts an apoptotic modulator part. It has been shown that blocking the E.G.F.R. way acts on three levels: accumulation of ells in phase G1, reduction of the cell repair and increasing of apoptosis. he inhibition of post irradiation action of the E.G.F.R. signal way is a factor explaining the ionizing radiation - anti E.G.F.R. synergy. The preclinical data suggest that the E.G.F.R. blocking by the monoclonal antibodies is more important than the use of tyrosine kinase inhibitors. A first positive randomized study with the cetuximab, published in 2006 in the epidermoid carcinomas of the O.R.L. sphere lead to its authorization on the market with the radiotherapy for this localization. The use of cetuximab in other indication with or in

  5. A transcription factor active on the epidermal growth factor receptor gene

    International Nuclear Information System (INIS)

    Kageyama, R.; Merlino, G.T.; Pastan, I.

    1988-01-01

    The authors have developed an in vitro transcription system for the epidermal growth factor receptor (EGFR) oncogene by using nuclear extracts of A431 human epidermoid carcinoma cells, which overproduce EGFR. They found that a nuclear factor, termed EGFR-specific transcription factor (ETF), specifically stimulated EGFR transcription by 5- to 10-fold. In this report, ETF, purified by using sequence-specific oligonucleotide affinity chromatography, is shown by renaturing material eluted from a NaDodSO 4 /polyacrylamide gel to be a protein with a molecular mass of 120 kDa. ETF binds to the promoter region, as measured by DNase I footprinting and gel-mobility-shift assays, and specifically stimulates the transcription of the EGFR gene in a reconstituted in vitro transcription system. These results suggest that ETF could play a role in the overexpression of the cellular oncogene EGFR

  6. Markedly diminished epidermal keratinocyte expression of intercellular adhesion molecule-1 (ICAM-1) in Sezary syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Nickoloff, B.J.; Griffiths, E.M.; Baadsgaard, O.; Voorhees, J.J.; Hanson, C.A.; Cooper, K.D. (Univ. of Michigan Medical Center, Ann Arbor (USA))

    1989-04-21

    In mucosis fungoides the malignant T cells express lymphocyte function-associated antigen-1, which allows them to bind to epidermal keratinocytes expressing the gamma interferon-inducible intercellular adhesion molecule-1. In this report, a patient with leukemic-stage mucosis fungoides (Sezary syndrome) had widespread erythematous dermal infiltrates containing malignant T cells, but without any epidermotropism. The authors discovered that the T cells expressed normal amounts of functional lymphocyte function-associated antigen-1, but the keratinocytes did not express significant levels of intercellular adhesion molecule-1, which was probably due to the inability of the malignant T cells to produce gamma interferon. These results support the concept that the inability of malignant T cells to enter the epidermis may contribute to emergence of more clinically aggressive T-cell clones that are no longer confined to the skin, but infiltrate the blood, lymph nodes, and viscera, as is seen in Sezary syndrome.

  7. Delayed Hepatic Adaptation to Weaning in ACBP(-/-) Mice Is Caused by Disruption of the Epidermal Barrier

    DEFF Research Database (Denmark)

    Neess, Ditte; Bek, Signe; Bloksgaard, Maria

    2013-01-01

    in the skin rather than in the liver. Similarly to ACBP(-/-) mice, K14-ACBP(-/-) mice exhibit an increased transepidermal water loss, and we show that the hepatic phenotype is caused specifically by the epidermal barrier defect, which leads to increased lipolysis in white adipose tissue. Our data demonstrate......We previously reported that mice deficient in acyl-CoA-binding protein (ACBP) display a delayed metabolic adaptation to weaning. This includes a delayed activation of the hepatic lipogenic gene program, which may result from hepatic accumulation of triacylglycerol and/or cholesteryl esters...... in the late suckling period. To further investigate the basis for this phenotype, we generated mice deficient in ACBP in hepatocytes (Alb-ACBP(-/-)) and keratinocytes (K14-ACBP(-/-)). Surprisingly, the delayed adaptation to weaning, including hepatic lipid accumulation, is caused by ACBP deficiency...

  8. Notch-deficient skin induces a lethal systemic B-lymphoproliferative disorder by secreting TSLP, a sentinel for epidermal integrity.

    Directory of Open Access Journals (Sweden)

    Shadmehr Demehri

    2008-05-01

    Full Text Available Epidermal keratinocytes form a highly organized stratified epithelium and sustain a competent barrier function together with dermal and hematopoietic cells. The Notch signaling pathway is a critical regulator of epidermal integrity. Here, we show that keratinocyte-specific deletion of total Notch signaling triggered a severe systemic B-lymphoproliferative disorder, causing death. RBP-j is the DNA binding partner of Notch, but both RBP-j-dependent and independent Notch signaling were necessary for proper epidermal differentiation and lipid deposition. Loss of both pathways caused a persistent defect in skin differentiation/barrier formation. In response, high levels of thymic stromal lymphopoietin (TSLP were released into systemic circulation by Notch-deficient keratinocytes that failed to differentiate, starting in utero. Exposure to high TSLP levels during neonatal hematopoiesis resulted in drastic expansion of peripheral pre- and immature B-lymphocytes, causing B-lymphoproliferative disorder associated with major organ infiltration and subsequent death, a previously unappreciated systemic effect of TSLP. These observations demonstrate that local skin perturbations can drive a lethal systemic disease and have important implications for a wide range of humoral and autoimmune diseases with skin manifestations.

  9. Expression and significance of HMGB1, TLR4 and NF-κB p65 in human epidermal tumors

    International Nuclear Information System (INIS)

    Weng, Hui; Deng, Yunhua; Xie, Yuyan; Liu, Hongbo; Gong, Feili

    2013-01-01

    High mobility group protein box 1 (HMGB1) is a DNA binding protein located in nucleus. It is released into extracellular fluid where it acts as a novel proinflammatory cytokine which interacts with Toll like receptor 4 (TLR4) to activate nuclear factor-κB (NF-κB). This sequence of events is involved in tumor growth and progression. However, the effects of HMGB1, TLR4 and NF-κB on epidermal tumors remain unclear. Human epidermal tumor specimens were obtained from 96 patients. Immunohistochemistry was used to detect expression of HMGB1, TLR4 and NF-κB p65 in human epidermal tumor and normal skin specimens. Western blot analysis was used to detect the expression of NF-κB p65 in epithelial cell nuclei in human epidermal tumor and normal tissues. Immunohistochemistry and western blot analysis indicated a progressive but statistically significant increase in p65 expression in epithelial nuclei in benign seborrheic keratosis (SK), precancerous lesions (PCL), low malignancy basal cell carcinoma (BCC) and high malignancy squamous cell carcinoma (SCC) (P <0.01). The level of extracellular HMGB1 in SK was significantly higher than in normal skin (NS) (P <0.01), and was higher than in SCC but without statistical significance. The level of TLR4 on epithelial membranes of SCC cells was significantly higher than in SK, PCL, BCC and NS (P <0.01). There was a significant positive correlation between p65 expression in the epithelial nuclei and TLR4 expression on the epithelial cell membranes (r = 0.3212, P <0.01). These findings indicate that inflammation is intensified in parallel with increasing malignancy. They also indicate that the TLR4 signaling pathway, rather than HMGB1, may be the principal mediator of inflammation in high-grade malignant epidermal tumors. Combined detection of p65 in the epithelial nuclei and TLR4 on the epithelial membranes may assist the accurate diagnosis of malignant epidermal tumors

  10. Self-phosphorylation of epidermal growth factor receptor: evidence for a model of intermolecular allosteric activation

    International Nuclear Information System (INIS)

    Yarden, Y.; Schlessinger, J.

    1987-01-01

    The membrane receptor for epidermal growth factor (EGF) is a 170,000 dalton glycoprotein composed of an extracellular EGF-binding domain and a cytoplasmic kinase domain connected by a stretch of 23 amino acids traversing the plasma membrane. The binding of EGF to the extracellular domain activates the cytoplasmic kinase function even in highly purified preparations of EGF receptor, suggesting that the activation occurs exclusively within the EGF receptor moiety. Conceivably, kinase activation may require the transfer of a conformational change through the single transmembrane region from the ligand binding domain to the cytoplasmic kinase region. Alternatively, ligand-induced receptor-receptor interactions may activate the kinase and thus bypass this requirement. Both mechanisms were contrasted by employing independent experimental approaches. On the basis of these results, an allosteric aggregation model is formulated for the activation of the cytoplasmic kinase function of the receptor by EGF. This model may be relevant to the mechanism by which the mitogenic signal of EGF is transferred across the membrane

  11. [Morphology research of the rat sciatic nerve bridged by collage-heparin sulfate scaffold].

    Science.gov (United States)

    Wang, Shu-sen; Hu, Yun-yu; Luo, Zhuo-jing; Chen, Liang-wei; Liu, Hui-ling; Meng, Guo-lin; Lü, Rong; Xu, Xin-zhi

    2005-04-15

    To observe the treating effect of collage-heparin sulfate after the 10 mm rat sciatic nerve defect was bridged by it. A new kind of nervous tissue engineering scaffold was produced by freeze-drying technique from collagen-heparin sulfate. Thirty-two SD rats were randomly divided into A, B, C and D groups. Sciatic nerve defect in group A was bridged by collagen-heparin sulfate. In group B, sciatic nerve was bridged by auto-nerve transplantation. Group C was the blank control group. Animals in group D were normal. And 10 mm sciatic nerve defect was bridged in the experiment. Thirty-six weeks after the operation, the experimental animals were detected by HRP labeled retrograde trace, HE staining, toluidine staining, silvering staining, S100, GAP-43 and NF immunohistological staining, MBP immunofluorescence staining and transmission electron microscope to observe the nerve regeneration inducing effect of this new scaffold. Nine months after operation, the collage-heparin sulfate scaffold was replaced by newly regenerated nerve. The number of HRP labeled spinal cord anterior horn cells and the area of sensation nerve fiber at the posterior horn were similar with that was repaired by auto-nerve. GAP-43, NF and S100 labeled regenerated nerve fiber had passed the total scaffold and entered the distal terminal. The regenerated nerve fibers were paralleled, lineage arranged, coincide with the prearranged regenerating "channel" in the collagen-heparin sulfate scaffold. MBP immunofluorescence staining also proved that the newly regenerated nerve fiber could be ensheathed. In the experimental group, the area of myelinated nerve fiber and the thickness of the myelin sheath had no obvious difference with that of the group repaired by auto-nerve, except that the density of the regenerated myelinated sheath fiber was lower than that of the control group. Nervous tissue engineering scaffold produced by collagen-heparin sulfate can guide the regeneration of nerve fibers. The nerve

  12. Inhibition of epidermal cell proliferation by borderline rays

    Energy Technology Data Exchange (ETDEWEB)

    Born, W [Freiburg Univ.; Daikeler, G

    1976-08-01

    Treatment of guinea pig flanks with very soft x-rays (borderline rays) directly caused a partial block of epidermal DNA synthesis which had been determined by measuring the /sup 3/H-Tdr incorporation. Higher doses and repeated applications would undoubtedly cause lasting damage to the tissue. The enhanced epidermal DNA synthesis which is sometimes observed should not be misinterpreted as a sign of a directly biopositive utilisation of the quantum energy supplied. Rather, it is a secondary repair process following initial phases of depression. A reparative increase in DNA synthesis may also occur as a primary process if the radiation is almost completely absorbed above the germinative layer.

  13. Epidermal growth factor in mammary glands and milk from rats

    DEFF Research Database (Denmark)

    Thulesen, J; Raaberg, Lasse; Nexø, Ebba

    1993-01-01

    Epidermal growth factor (EGF) is one of the major growth-promoting agents in milk. Using immunohistochemistry we localized EGF in the mammary glands of lactating rats to the luminal border of the secretory cells. Following proteolytic pretreatment of the histological sections, the EGF-immunoreact......Epidermal growth factor (EGF) is one of the major growth-promoting agents in milk. Using immunohistochemistry we localized EGF in the mammary glands of lactating rats to the luminal border of the secretory cells. Following proteolytic pretreatment of the histological sections, the EGF...

  14. Selection of DNA aptamers against epidermal growth factor receptor with high affinity and specificity

    International Nuclear Information System (INIS)

    Wang, Deng-Liang; Song, Yan-Ling; Zhu, Zhi; Li, Xi-Lan; Zou, Yuan; Yang, Hai-Tao; Wang, Jiang-Jie; Yao, Pei-Sen; Pan, Ru-Jun; Yang, Chaoyong James; Kang, De-Zhi

    2014-01-01

    Highlights: • This is the first report of DNA aptamer against EGFR in vitro. • Aptamer can bind targets with high affinity and selectivity. • DNA aptamers are more stable, cheap and efficient than RNA aptamers. • Our selected DNA aptamer against EGFR has high affinity with K d 56 ± 7.3 nM. • Our selected DNA aptamer against EGFR has high selectivity. - Abstract: Epidermal growth factor receptor (EGFR/HER1/c-ErbB1), is overexpressed in many solid cancers, such as epidermoid carcinomas, malignant gliomas, etc. EGFR plays roles in proliferation, invasion, angiogenesis and metastasis of malignant cancer cells and is the ideal antigen for clinical applications in cancer detection, imaging and therapy. Aptamers, the output of the systematic evolution of ligands by exponential enrichment (SELEX), are DNA/RNA oligonucleotides which can bind protein and other substances with specificity. RNA aptamers are undesirable due to their instability and high cost of production. Conversely, DNA aptamers have aroused researcher’s attention because they are easily synthesized, stable, selective, have high binding affinity and are cost-effective to produce. In this study, we have successfully identified DNA aptamers with high binding affinity and selectivity to EGFR. The aptamer named TuTu22 with K d 56 ± 7.3 nM was chosen from the identified DNA aptamers for further study. Flow cytometry analysis results indicated that the TuTu22 aptamer was able to specifically recognize a variety of cancer cells expressing EGFR but did not bind to the EGFR-negative cells. With all of the aforementioned advantages, the DNA aptamers reported here against cancer biomarker EGFR will facilitate the development of novel targeted cancer detection, imaging and therapy

  15. Selection of DNA aptamers against epidermal growth factor receptor with high affinity and specificity

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Deng-Liang [The First Clinical Medical College of Fujian Medical University, Fuzhou (China); Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou (China); Song, Yan-Ling; Zhu, Zhi; Li, Xi-Lan; Zou, Yuan [State Key Laboratory for Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Key Laboratory of Analytical Chemistry, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Yang, Hai-Tao; Wang, Jiang-Jie [The First Clinical Medical College of Fujian Medical University, Fuzhou (China); Yao, Pei-Sen [Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou (China); Pan, Ru-Jun [The First Clinical Medical College of Fujian Medical University, Fuzhou (China); Yang, Chaoyong James, E-mail: cyyang@xmu.edu.cn [State Key Laboratory for Physical Chemistry of Solid Surfaces, Key Laboratory for Chemical Biology of Fujian Province, Key Laboratory of Analytical Chemistry, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Kang, De-Zhi, E-mail: kdzy99988@163.com [The First Clinical Medical College of Fujian Medical University, Fuzhou (China); Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou (China)

    2014-10-31

    Highlights: • This is the first report of DNA aptamer against EGFR in vitro. • Aptamer can bind targets with high affinity and selectivity. • DNA aptamers are more stable, cheap and efficient than RNA aptamers. • Our selected DNA aptamer against EGFR has high affinity with K{sub d} 56 ± 7.3 nM. • Our selected DNA aptamer against EGFR has high selectivity. - Abstract: Epidermal growth factor receptor (EGFR/HER1/c-ErbB1), is overexpressed in many solid cancers, such as epidermoid carcinomas, malignant gliomas, etc. EGFR plays roles in proliferation, invasion, angiogenesis and metastasis of malignant cancer cells and is the ideal antigen for clinical applications in cancer detection, imaging and therapy. Aptamers, the output of the systematic evolution of ligands by exponential enrichment (SELEX), are DNA/RNA oligonucleotides which can bind protein and other substances with specificity. RNA aptamers are undesirable due to their instability and high cost of production. Conversely, DNA aptamers have aroused researcher’s attention because they are easily synthesized, stable, selective, have high binding affinity and are cost-effective to produce. In this study, we have successfully identified DNA aptamers with high binding affinity and selectivity to EGFR. The aptamer named TuTu22 with K{sub d} 56 ± 7.3 nM was chosen from the identified DNA aptamers for further study. Flow cytometry analysis results indicated that the TuTu22 aptamer was able to specifically recognize a variety of cancer cells expressing EGFR but did not bind to the EGFR-negative cells. With all of the aforementioned advantages, the DNA aptamers reported here against cancer biomarker EGFR will facilitate the development of novel targeted cancer detection, imaging and therapy.

  16. Prolonged Activated Clotting Time after Protamine Administration Does Not Indicate Residual Heparinization after Cardiopulmonary Bypass in Pediatric Open Heart Surgery.

    Science.gov (United States)

    Yamamoto, Tomohiro; Wolf, Hans-Gerd; Sinzobahamvya, Nicodème; Asfour, Boulos; Hraska, Victor; Schindler, Ehrenfried

    2015-08-01

    In open heart surgery, heparinization is commonly neutralized using an empirical heparin:protamine ratio ranging between 1:1 and 1:1.5. However, these ratios may result in protamine overdose that should be avoided for its negative side effects on the coagulation system. This study aimed to indicate the appropriate treatment for prolonged activated clotting time (ACT) after protamine administration following cardiopulmonary bypass (CPB) in pediatric open heart surgery by investigating the underlying reasons for it. Twenty-seven children (open heart surgery were included. Heparin was administered only before CPB (400 IU/kg) and in the pump priming volume for CPB (2,000 IU) and was neutralized by 1:1 protamine after CPB. The blood heparin concentration was measured using anti-Xa assay. ACT and blood concentrations of heparin, coagulation factors, thrombin-antithrombin complex, and prothrombin fragment 1 + 2 were assessed. A rotational thromboelastometry (ROTEM; Tem International GmbH, München, Bayern, Germany) was used to confirm the coagulation status and residual heparin after protamine administration. Anti-Xa assay showed that there is no residual heparin in the blood after 1:1 protamine administration. Nevertheless, ACT (128.89 ± 3.09 seconds before heparin administration) remained prolonged (177.14 ± 5.43 seconds at 10 minutes after protamine, 182.00 ± 5.90 seconds at 30 minutes after protamine). The blood concentrations of coagulation factors were significantly lower than those before heparin administration (p < 0.01). The low FIBTEM MCF of ROTEM (4.43 ± 0.32 mm) at 10 minutes after protamine indicated low fibrinogen concentration. Prolonged ACT after heparin neutralization by 1:1 protamine administration does not necessarily indicate residual heparin, but low blood concentrations of coagulation factors should be considered as a reason as well. Accordingly, supply of coagulation factors instead of additional protamine should be

  17. Influência da heparina sódica na ocorrência de laminite eqüina induzida por sobrecarga de carboidratos Influence of heparin in occurrence of carbohydrate overload-induced equine laminitis

    Directory of Open Access Journals (Sweden)

    L.P. Martins Filho

    2008-12-01

    intravenous administration of 5ml of acepromazine followed by 1g of thiopental sodium and 1 liter of saturated solution of KCl to obtain hoof tissues samples for histological examination. GII and GIII horses developed laminitis, showing lameness 12 and 24h after carbohydrate administration, respectively, as well increased heart rate and capillary refill time. The histological alterations, similar in GII and GIII, were degenerative lesions, as thinness of epidermal lamina, retraction, flattening and dislocation of the dermal lamina, epidermal vacuolization, and disruption of the epidermal tissues. The occurrence of laminar degeneration was not prevented or attenuated with intravenous heparin administration.

  18. Taurolidine lock is superior to heparin lock in the prevention of catheter related bloodstream infections and occlusions.

    Directory of Open Access Journals (Sweden)

    Evelyn D Olthof

    Full Text Available Patients on home parenteral nutrition (HPN are at risk for catheter-related complications; mainly infections and occlusions. We have previously shown in HPN patients presenting with catheter sepsis that catheter locking with taurolidine dramatically reduced re-infections when compared with heparin. Our HPN population therefore switched from heparin to taurolidine in 2008. The aim of the present study was to compare long-term effects of this catheter lock strategy on the occurrence of catheter-related bloodstream infections and occlusions in HPN patients.Data of catheter-related complications were retrospectively collected from 212 patients who received HPN between January 2000 and November 2011, comprising 545 and 200 catheters during catheter lock therapy with heparin and taurolidine, respectively. We evaluated catheter-related bloodstream infection and occlusion incidence rates using Poisson-normal regression analysis. Incidence rate ratios were calculated by dividing incidence rates of heparin by those of taurolidine, adjusting for underlying disease, use of anticoagulants or immune suppressives, frequency of HPN/fluid administration, composition of infusion fluids, and duration of HPN/fluid use before catheter creation.Bloodstream infection incidence rates were 1.1/year for heparin and 0.2/year for taurolidine locked catheters. Occlusion incidence rates were 0.2/year for heparin and 0.1/year for taurolidine locked catheters. Adjusted incidence ratios of heparin compared to taurolidine were 5.9 (95% confidence interval, 3.9-8.7 for bloodstream infections and 1.9 (95% confidence interval, 1.1-3.1 for occlusions.Given that no other procedural changes than the catheter lock strategy were implemented during the observation period, these data strongly suggest that taurolidine decreases catheter-related bloodstream infections and occlusions in HPN patients compared with heparin.

  19. Influence of epidermal growth factor on liver regeneration after partial hepatectomy in rats

    DEFF Research Database (Denmark)

    Olsen, Peter Skov; Boesby, S.; Kirkegaard, P.

    2013-01-01

    The role of epidermal growth factor on liver regeneration after partial hepatectomy in rats was investigated. After a 70% hepatectomy in rats, the concentration of epidermal growth factor in portal venous blood was unchanged compared with unoperated controls. However, small amounts of epidermal...... growth factor could be identified in portal venous blood after intestinal instillation of epidermal growth factor. Brunner's glands and the submandibular glands secrete epidermal growth factor. Extirpation of Brunner's glands decreased liver regeneration, whereas removal of the submandibular glands had...... no effect on liver regeneration. Epidermal growth factor antiserum reduced liver regeneration significantly. Oral or s.c. administration of epidermal growth factor had no effect on liver regeneration, whereas epidermal growth factor enhanced the effect of insulin and glucagon on liver regeneration...

  20. Influence of Human Leukocyte Antigen (HLA) Alleles and Killer Cell Immunoglobulin-Like Receptors (KIR) Types on Heparin-Induced Thrombocytopenia (HIT).

    Science.gov (United States)

    Karnes, Jason H; Shaffer, Christian M; Cronin, Robert; Bastarache, Lisa; Gaudieri, Silvana; James, Ian; Pavlos, Rebecca; Steiner, Heidi E; Mosley, Jonathan D; Mallal, Simon; Denny, Joshua C; Phillips, Elizabeth J; Roden, Dan M

    2017-09-01

    Heparin-induced thrombocytopenia (HIT) is an unpredictable, life-threatening, immune-mediated reaction to heparin. Variation in human leukocyte antigen (HLA) genes is now used to prevent immune-mediated adverse drug reactions. Combinations of HLA alleles and killer cell immunoglobulin-like receptors (KIR) are associated with multiple autoimmune diseases and infections. The objective of this study is to evaluate the association of HLA alleles and KIR types, alone or in the presence of different HLA ligands, with HIT. HIT cases and heparin-exposed controls were identified in BioVU, an electronic health record coupled to a DNA biobank. HLA sequencing and KIR type imputation using Illumina OMNI-Quad data were performed. Odds ratios for HLA alleles and KIR types and HLA*KIR interactions using conditional logistic regressions were determined in the overall population and by race/ethnicity. Analysis was restricted to KIR types and HLA alleles with a frequency greater than 0.01. The p values for HLA and KIR association were corrected by using a false discovery rate qHIT cases and 350 matched controls were identified. No statistical differences in baseline characteristics were observed between cases and controls. The HLA-DRB3*01:01 allele was significantly associated with HIT in the overall population (odds ratio 2.81 [1.57-5.02], p=2.1×10 -4 , q=0.02) and in individuals with European ancestry, independent of other alleles. No KIR types were associated with HIT, although a significant interaction was observed between KIR2DS5 and the HLA-C1 KIR binding group (p=0.03). The HLA-DRB3*01:01 allele was identified as a potential risk factor for HIT. This class II HLA gene and allele represent biologically plausible candidates for influencing HIT pathogenesis. We found limited evidence of the role of KIR types in HIT pathogenesis. Replication and further study of the HLA-DRB3*01:01 association is necessary. © 2017 Pharmacotherapy Publications, Inc.

  1. Inversion of lithium heparin gel tubes after centrifugation is a significant source of bias in clinical chemistry testing.

    Science.gov (United States)

    Lippi, Giuseppe; Salvagno, Gian Luca; Danese, Elisa; Lima-Oliveira, Gabriel; Brocco, Giorgio; Guidi, Gian Cesare

    2014-09-25

    This study was planned to establish whether random orientation of gel tubes after centrifugation may impair sample quality. Eight gel tubes were collected from 17 volunteers: 2 Becton Dickinson (BD) serum tubes, 2 Terumo serum tubes, 2 BD lithium heparin tubes and 2 Terumo lithium heparin tubes. One patient's tube for each category was kept in a vertical, closure-up position for 90 min ("upright"), whereas paired tubes underwent bottom-up inversion every 15 min, for 90 min ("inverted"). Immediately after this period of time, 14 clinical chemistry analytes, serum indices and complete blood count were then assessed in all tubes. Significant increases were found for phosphate and lipaemic index in all inverted tubes, along with AST, calcium, cholesterol, LDH, potassium, hemolysis index, leukocytes, erythrocytes and platelets limited to lithium heparin tubes. The desirable quality specifications were exceeded for AST, LDH, and potassium in inverted lithium heparin tubes. Residual leukocytes, erythrocytes, platelets and cellular debris were also significantly increased in inverted lithium heparin tubes. Lithium heparin gel tubes should be maintained in a vertical, closure-up position after centrifugation. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Comparison of Efficacy Compressive Stockings with Heparin in Prevention of Deep Vein Thrombosis in Stroke Patients

    Directory of Open Access Journals (Sweden)

    Nastaran Majdi-Nasab

    2013-04-01

    Full Text Available Background: The present study is carried out to make a comparison between two pharmacological (heparin and physical (compression stockings in the prevention of deep vein thrombosis in lower limb of the patients suffered from acute stroke. Materials and Methods: In this investigation as a clinical trial, the effectiveness of the above methods on 100 patients with the stroke was compared in two groups of 50 persons. Results: Three patients in physical group and two patients in pharmacological group got deep vein thrombosis that showed no significant difference between two groups.Conclusion: In spite of no significant relationship and due to less incurrence of thrombosis in heparin group, it is more reasonable to use pharmacological methods.

  3. Low molecular weight heparins in the prevention of deep-vein thrombosis in general surgery.

    Science.gov (United States)

    Breddin, H K

    1999-01-01

    Unfractionated heparin (UFH) was the established treatment in the early 1980s for the prophylaxis of venous thromboembolic disease (VTED) in patients undergoing general surgery. This was one of the earliest indications in which low molecular weight heparins (LMWHs) were tested, and about 40 trials have revealed that these agents are at least as effective and safe as UFH with a tendency of superiority when higher dosages are used. In most trials, the fibrinogen uptake test has been used to assess the frequency of deep vein thrombosis. LMWHs exhibit a number of improved features over UFH, including ease of administration and convenient once daily dosing, facilitating outpatient management. A still open question is the ideal time and dose of the first one or two injections of a LMWH. To determine the clinical relevance of product differentiation further, clinical trials, directly comparing different LMWHs, are required.

  4. Disparate effects of heparin on free thyroxine measured by two different radioimmunoassays

    International Nuclear Information System (INIS)

    McDougall, I.R.; Bayer, M.F.; Nierenberg, D.; Lewis, S.J.

    1983-01-01

    Heparin causes a rise in free thyroxine (FT4) measured by equilibrium dialysis (E.D.). With the introduction of at least 4 commercial radioimmunoassays (RIA) for FT4, FT4 measurements have become accepted as one of the best routine thyroid function tests. Investigators have indicated that FT4 levels determined by RIA may be of particular value in patients hospitalized for various severe nonthyroidal illnesses in whom conventional thyroid function tests tend to be abnormal. However, very little information is as yet available on possible effects of various drugs on FT4 levels measured by these new methods. A study was undertaken to evaluate the effect of heparin on FT4 measured by 2 different RIA procedures: RIA-I, GammaCoat FT4 by clinical Assays and RIA-II, Amerlex FT4 by Amersham

  5. Heparin Assisted Photochemical Synthesis of Gold Nanoparticles and Their Performance as SERS Substrates

    Science.gov (United States)

    Rodríguez-Torres, Maria del Pilar; Díaz-Torres, Luis Armando; Romero-Servin, Sergio

    2014-01-01

    Reactive and pharmaceutical-grade heparins were used as biologically compatible reducing and stabilizing agents to photochemically synthesize colloidal gold nanoparticles. Aggregates and anisotropic shapes were obtained photochemically under UV black-light lamp irradiation (λ = 366 nm). Heparin-functionalized gold nanoparticles were characterized by Scanning Electron Microscopy and UV-Vis spectroscopy. The negatively charged colloids were used for the Surface Enhanced Raman Spectroscopy (SERS) analysis of differently charged analytes (dyes). Measurements of pH were taken to inspect how the acidity of the medium affects the colloid-analyte interaction. SERS spectra were taken by mixing the dyes and the colloidal solutions without further functionalization or addition of any aggregating agent. PMID:25342319

  6. [Obstetrical APS: Is there a place for additional treatment to aspirin-heparin combination?

    Science.gov (United States)

    Mekinian, A; Kayem, G; Cohen, J; Carbillon, L; Abisror, N; Josselin-Mahr, L; Bornes, M; Fain, O

    2017-01-01

    Obstetrical APS is defined by thrombosis and/or obstetrical morbidity associated with persistent antiphospholipid antibodies. The aspirin and low molecular weighted heparin combination dramatically improved obstetrical outcome in APS patients. Several factors could be associated with obstetrical prognosis, as previous history of thrombosis, associated SLE, the presence of lupus anticoagulant and triple positivity of antiphospholipid antibodies. Obstetrical APS with isolated recurrent miscarriages is mostly associated with isolated anticardiolipids antibodies and have better obstetrical outcome. The pregnancy loss despite aspirin and heparin combination define the refractory obstetrical APS, and the prevalence could be estimated to 20-39%. Several other treatments have been used in small and open labeled studies, as steroids, intravenous immunoglobulins, plasma exchanges and hydroxychloroquine to improve the obstetrical outcome. Some other drugs as eculizumab and statins could also have physiopathological rational, but studies are necessary to define the place of these various drugs. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  7. Low-thrombogenic fibrin-heparin coating promotes in vitro endothelialization

    Czech Academy of Sciences Publication Activity Database

    Kaplan, Ondřej; Hierlemann, T.; Krajewski, S.; Kurz, J.; Nevoralová, Martina; Houska, Milan; Riedel, Tomáš; Riedelová, Zuzana; Zárubová, Jana; Wendel, H. P.; Brynda, Eduard

    2017-01-01

    Roč. 105, č. 11 (2017), s. 2995-3005 ISSN 1549-3296 R&D Projects: GA MZd(CZ) NV15-29153A Institutional support: RVO:61389013 ; RVO:67985823 Keywords : fibrin-heparin coating * hemocompatibility * endothelialization Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery; FA - Cardiovascular Diseases incl. Cardiotharic Surgery (FGU-C) OBOR OECD: Cardiac and Cardiovascular systems; Cardiac and Cardiovascular systems (FGU-C) Impact factor: 3.076, year: 2016

  8. Relationship between heparin anticoagulation and clinical outcomes in coronary stent intervention: observations from the ESPRIT trial.

    Science.gov (United States)

    Tolleson, Thaddeus R; O'Shea, J Conor; Bittl, John A; Hillegass, William B; Williams, Kathryn A; Levine, Glenn; Harrington, Robert A; Tcheng, James E

    2003-02-05

    We evaluated the relationship between the degree of heparin anticoagulation and clinical efficacy and bleeding in patients undergoing contemporary percutaneous coronary intervention (PCI) with stent implantation. Despite universal acceptance of heparin anticoagulation as a standard of care in PCI, considerable controversy still exists regarding the appropriate dosing of heparin. The study population (n = 2,064) comprised all patients enrolled in the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial. The index activated clotting time (ACT) was defined as the ACT measured after the last heparin dose and before first device activation and was correlated with outcome and bleeding events. No association was observed between decreasing ACT levels and the rate of ischemic events in the treatment or placebo arms. The incidence of the primary composite end point (death, myocardial infarction, urgent target vessel revascularization, and thrombotic bailout glycoprotein IIb/IIIa inhibitor therapy at 48 h) was actually lowest in the lowest ACT tertile for both the placebo (10.0%) and treatment groups (6.1%). When analyzed by tertile, major bleeding rates did not increase in the lowest ACT tertile in patients given placebo (0.6%) versus those receiving eptifibatide (0.7%). Major bleeding rates increased as the ACT increased in the eptifibatide-treated patients. Ischemic end points in patients undergoing contemporary PCI with stent placement do not increase by decreasing ACT levels, at least to a level of 200 s. Bleeding events do increase with increasing ACT levels and are enhanced with eptifibatide treatment. An ACT of 200 to 250 s is reasonable in terms of efficacy and safety with the use of contemporary technology and pharmacotherapy.

  9. Human Endothelial Cells: Use of Heparin in Cloning and Long-Term Serial Cultivation

    Science.gov (United States)

    Thornton, Susan C.; Mueller, Stephen N.; Levine, Elliot M.

    1983-11-01

    Endothelial cells from human blood vessels were cultured in vitro, with doubling times of 17 to 21 hours for 42 to 79 population doublings. Cloned human endothelial cell strains were established for the first time and had similar proliferative capacities. This vigorous cell growth was achieved by addition of heparin to culture medium containing reduced concentrations of endothelial cell growth factor. The routine cloning and long-term culture of human endothelial cells will facilitate studying the human endothelium in vitro.

  10. Cefotaxime-heparin lock prophylaxis against hemodialysis catheter-related sepsis among Staphylococcus aureus nasal carriers

    Directory of Open Access Journals (Sweden)

    Anil K Saxena

    2012-01-01

    Full Text Available Staphylococcus aureus nasal carriers undergoing hemodialysis (HD through tunneled cuffed catheters (TCCs form a high-risk group for the development of catheter-related bloodstream infections (CRBSI and ensuing morbidity. The efficacy of antibiotic-locks on the outcomes of TCCs among S. aureus nasal carriers has not been studied earlier. Persistent nasal carriage was defined by two or more positive cultures for methicillin-susceptible (MSSA or methicillin-resistant (MRSA S. aureus of five standardized nasal swabs taken from all the participants dialyzed at a large out-patient HD center affiliated to a tertiary care hospital. Of 218 participants, 82 S. aureus nasal carriers dialyzed through TCCs (n = 88 were identified through April 2005 to March 2006 and randomized to two groups. Group I comprised of 39 nasal carriers who had TCCs (n = 41 "locked" with cefotaxime/heparin while group II included 43 patients with TCCs (n = 47 filled with standard heparin. The CRBSI incidence and TCC survival at 365 days were statistically compared between the two groups. A significantly lower CRBSI incidence (1.47 vs. 3.44/1000 catheter-days, P <0.001 and higher infection-free TCC survival rates at 365 days (80.5 vs. 40.4%, P <0.0001 were observed in the cefotaxime group compared with the stan-dard heparin group. However, no significant difference in MRSA-associated CRBSI incidence was observed between the two groups. Cefotaxime-heparin "locks" effectively reduced CRBSI-incidence associated with gram-positive cocci, including MSSA, among S. aureus nasal carriers. There remains a compelling requirement for antibiotic-locks effective against MRSA.

  11. Bilateral rectal sheath hematomas after low-molecular weight heparin treatment in uremia.

    Science.gov (United States)

    Xu, Lu; Liu, Lei; Li, Xinjian

    2017-11-01

    Rectus sheath hematomas (RSHs) are uncommon. They are usually unilateral and rarely bilateral. In this paper, we report the first case of spontaneous bilateral RSHs in a uremic patient after the administration of the first dose of low-molecular weight heparin during hemodialysis. The most interesting aspect of this case is that the main symptom of RSH in our patient was urinary bladder irritation. We highlight the importance of the prompt diagnosis and management of this medical emergency.

  12. LOW-MOLECULAR-WEIGHT HEPARIN TREATMENT FAILURE IN PREVENTION OF PROSTHETIC MITRAL VALVE THROMBOSIS

    OpenAIRE

    David Šuran; Vojko Kanič; Tatjana Golob Gulič; Husam Franjo Naji; Robert Lipovec

    2009-01-01

    Background Prosthetic heart valve thrombosis (PHVT) represents a dangerous postoperative complication following prosthetic heart valve replacement. Incidence varies according to different data from 0.5–4 % per year following mitral or aortic valve replacement in spite of adequate oral anticoagulation with coumarins. Case report We are presenting a case of prosthetic mitral valve thrombosis as a result of 6-month lowmolecular-weight heparin (LMWH) (nadroparine) treatment failure. Our pat...

  13. Obstacles in the diagnostics and therapy of heparin-induced thrombocytopenia.

    Science.gov (United States)

    Antonijević, Nebojsa M; Radovanović, Nebojsa; Obradović, Slobodan; Vucelić, Dragica; Stojanović, Bojan; Miković, Danijela; Kovac, Mirjana; Kocica, Tina; Tadić, Svetlana; Antonijević, Irina; Drasković, Snezana; Djordjević, Valentina; Calija, Branko; Perunicić, Jovan; Vasiljević, Zorana

    2010-01-01

    An immune-mediated, severe, acquired prothrombotic disorder, heparin-induced thrombocytopenia type II (HIT II) occurs in 0.5-5% of patients exposed to unfractionated heparin longer than 5-7 days. Arterial and venous thromboses are induced by HIT II in about 35-50% of patients. Typical death rate for HIT is about 29%, while 21% of HIT patients result in amputation of a limb. The trend towards the occurrence of HIT due to the administration of low molecular weight heparins (LMWH) taking ever conspicuous place in the standard venous thromboembolism (VTE) prophylaxis has been more frequently observed recently. It is considered that LMWH may cause HIT II in about 0.25-1%. The need for further modification of HIPA assays with LMWH has been imposed in the HIT laboratory diagnostics, heretofore overburdened with complexity. There are several constantly opposing problems arising in HIT laboratory diagnostics, one of which is that in a certain number of patients immunologic assays detect nonpathogenic antibodies (mainly IgM or IgA heparin-PF4 antibodies) while, on the other hand, the occurrence of HIT pathogenetically mediated by minor antigens (neutrophil-activating peptide 2 or interleukin 8) may be neglected in certain cases. The following factors play an important role in the interpretation of each laboratory HIT assays performed: 1. correlation with HIT clinical probability test, the best known of which is 4T'score, 2. the interpretation of the laboratory findings dependent on the time of the thrombocytopenia onset, as well as 3. the sensitivity and specificity of each test respectively. The HIT diagnostics in the presence of other comorbid states which may also induce thrombocytopenia, more precisely known as pseudo HIT (cancer, sepsis, disseminated intravascular coagulation, pulmonary embolism, antiphospholipid syndrome, etc), represents a specific clinical problem.

  14. Subcutis calcinosis caused by injection of calcium-containing heparin in a chronic kidney injury patient

    Directory of Open Access Journals (Sweden)

    Lilia Ben Fatma

    2014-01-01

    Full Text Available Subcutis calcinosis, characterized by abnormal calcium deposits in the skin, is a rare complication of using calcium-containing heparin occurring in patients with advanced renal failure. We report the case of an 83-year-old female, a known case of chronic kidney disease (CKD for four years with recent worsening of renal failure requiring hospitalization and hemodialysis. She developed subcutis calcinosis following injection of calcium-containing heparin. Biochemical tests showed serum parathormone level at 400 pg/dL, hypercalcemia, elevated calcium-phosphate product and monoclonal gammopathy related to multiple myeloma. She developed firm subcu-taneous nodules in the abdomen and the thighs, the injection sites of Calciparin ® (calcium nadroparin that was given as a preventive measure against deep vein thrombosis. The diagnosis of subcutis calcinosis was confirmed by the histological examination showing calcium deposit in the dermis and hypodermis. These lesions completely disappeared after discontinuing calcium nadro-parin injections. Subcutis calcinosis caused by injections of calcium-containing heparin is rare, and, to the best our knowledge, not more than 12 cases have been reported in the literature. Pathogenesis is not well established but is attributed to the calcium disorders usually seen in advanced renal failure. Diagnosis is confirmed by histological tests. Outcome is mostly favorable. The main differential diagnosis is calciphylaxis, which has a poor prognosis. Even though rarely reported, we should be aware that CKD patients with elevated calcium-phosphorus product can develop subcutis calcinosis induced by calcium-containing heparin. When it occurs, fortunately and unlike calci-phylaxis, outcome is favorable.

  15. Micromorphology and development of the epicuticular structure on the epidermal cell of ginseng leaves

    Directory of Open Access Journals (Sweden)

    Kyounghwan Lee

    2015-04-01

    Conclusion: The outwardly projected cuticle and epidermal cell wall (i.e., an epicuticular wrinkle acts as a major barrier to block out sunlight in ginseng leaves. The small vesicles in the peripheral region of epidermal cells may suppress the cuticle and parts of epidermal wall, push it upward, and consequently contribute to the formation of the epicuticular structure.

  16. Retrospective Study of Epidermal Parasitic Skin Diseases amongst ...

    African Journals Online (AJOL)

    ADOWIE PERE

    ABSTRACT: A ten year retrospective study (1997-2006) was undertaken to determine the prevalence of. Epidermal Parasitic Skin Diseases (EPSD) among out-patients from the skin diseases hospital in Maiduguri, Borno state. Out of 10,000 out-patients examined during the study period, 3527(35.27%) where infected with ...

  17. An immunologic approach to induction of epidermal growth factor deficiency

    DEFF Research Database (Denmark)

    Raaberg, Lasse; Nexø, Ebba; Poulsen, Steen Seier

    1995-01-01

    Epidermal growth factor (EGF) in pharmacologic doses is able to induce growth and development in the fetus and the newborn. To investigate the opposite situation, the effects of insufficient amounts of EGF during development, we wanted to establish an in vivo model with a state of EGF deficiency....

  18. Clinical Studies on conformal radiotherapy combined with epidermal ...

    African Journals Online (AJOL)

    Purpose: To study the effect of conformal radiotherapy combined with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) in the second-line treatment of non-small cell lung cancer (NSCLC). Methods: A total of 316 patients attending Shanghai Pulmonary Hospital affiliated to Tongji University, were divided ...

  19. Assessment of the Developmental Toxicity of Epidermal Growth ...

    African Journals Online (AJOL)

    Purpose: To determine whether epidermal growth factor (EGF) is involved in reproductive developmental toxicity, using the embryonic stem cell test (EST), as well as ascertain how EGF influences embryonic development. Methods: To predict developmental toxicity on the basis of reducing cell viability and inhibition of ...

  20. Pattern of hormone receptors and human epidermal growth factor ...

    African Journals Online (AJOL)

    Introduction: Breast cancer is the most common cancer among women globally. With immunohistochemistry (IHC), breast cancer is classified into four groups based on IHC profile of estrogen receptor (ER)/progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2/neu) expression, positive (+) and/or ...

  1. Adding a Piece to the Leaf Epidermal Cell Shape Puzzle.

    Science.gov (United States)

    von Wangenheim, Daniel; Wells, Darren M; Bennett, Malcolm J

    2017-11-06

    The jigsaw puzzle-shaped pavement cells in the leaf epidermis collectively function as a load-bearing tissue that controls organ growth. In this issue of Developmental Cell, Majda et al. (2017) shed light on how the jigsaw shape can arise from localized variations in wall stiffness between adjacent epidermal cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Gastric luminal epidermal growth factor is affected by diet | Iputo ...

    African Journals Online (AJOL)

    Objective. Diet is an area of major interest to those investigating the causes of cancer of the oesophagus in the Transkei. This study looked at the associations between intragastric epidermal growth factor level, diet and intragastric pH. Setting and subjects. A dietary survey was co-ordinated with studies of gastric luminal ...

  3. Epidermal hydration levels in rosacea patients improve after minocycline therapy.

    LENUS (Irish Health Repository)

    Ní Raghallaigh, S

    2013-12-06

    Patients with rosacea frequently report increased skin sensitivity, with features suggestive of an abnormal stratum corneum (SC) permeability barrier. Sebum, pH and hydration levels influence epidermal homeostasis. The correlation of the change in these parameters with clinically effective treatment has not been previously analysed.

  4. Inflammatory linear verrucous epidermal naevus: Report of three ...

    African Journals Online (AJOL)

    Background: Epidermal naevi are congenital harmatomas that arise from embryonal ectodermal cells. The inflammatory linear verrucous variant is rare and presents with disturbing symptoms. In blacks the classical erythema is not common but pruritus and discharge are the commonest features. Methods and results: We ...

  5. Identification of grazed grasses using epidermal characters | R ...

    African Journals Online (AJOL)

    The use of anatomical features of the abaxial epidermis of grasses is discussed for the identification of fragments of epidermis present in samples of rumen. The reliability of this technique, and the variation of the epidermal characters in two widely distributed species of grass, is given. A "Key" to identity certain genera of ...

  6. Improvement of arbutin trans-epidermal delivery using ...

    African Journals Online (AJOL)

    Purpose: To assess the ability of radiofrequency (RF) microporation to promote trans-epidermal delivery of arbutin. Methods: To investigate the enhancing effect of RF microchannels on skin permeation of arbutin, in vitro skin permeability studies were performed with RF microporation-treated Hartley albino guinea pig skin ...

  7. Platelet-derived growth factor inhibits platelet activation in heparinized whole blood.

    Science.gov (United States)

    Selheim, F; Holmsen, H; Vassbotn, F S

    1999-08-15

    We previously have demonstrated that human platelets have functionally active platelet-derived growth factor alpha-receptors. Studies with gel-filtered platelets showed that an autocrine inhibition pathway is transduced through this tyrosine kinase receptor during platelet activation. The physiological significance of this inhibitory effect of platelet-derived growth factor on gel-filtered platelets activation is, however, not known. In the present study, we investigated whether platelet-derived growth factor inhibits platelet activation under more physiological conditions in heparinized whole blood, which represents a more physiological condition than gel-filtered platelets. Using flow cytometric assays, we demonstrate here that platelet-derived growth factor inhibits thrombin-, thrombin receptor agonist peptide SFLLRN-, and collagen-induced platelet aggregation and shedding of platelet-derived microparticles from the platelet plasma membrane during platelet aggregation in stirred heparinized whole blood. The inhibitory effect of platelet-derived growth factor was dose dependent. However, under nonaggregating conditions (no stirring), we could not demonstrate any significant effect of platelet-derived growth factor on thrombin- and thrombin receptor agonist peptide-induced platelet surface expression of P-selectin. Our results demonstrate that platelet-derived growth factor appears to be a true antithrombotic agent only under aggregating conditions in heparinized whole blood.

  8. Influences of apolipoprotein E on soluble and heparin-immobilized hepatic lipase

    International Nuclear Information System (INIS)

    Landis, B.A.; Rotolo, F.S.; Meyers, W.C.; Clark, A.B.; Quarfordt, S.H.

    1987-01-01

    The effect of human apolipoprotein E (apoE), either alone or in combination with apoC, on the lipolysis of a radiolabeled triglyceride emulsion was studied with hepatic lipase in solution and immobilized on heparin-Sepharose. The soluble hepatic lipase was inhibited, whereas the heparin-immobilized lipase was stimulated by apoE. This stimulation was attenuated by combining apoE with either apoC-II or C-III. The heparin-immobilized lipase demonstrated much less lipolysis of the zwitterionic phosphatidylcholine-stabilized triglyceride emulsion than did the soluble enzyme. This difference was less when the emulsion was stabilized by a nonionic detergent. apoE inhibited lipase activity when assayed under conditions (0.4 M NaCl) of bound enzyme and unbound substrate. Increasing the emulsion apoE content beyond optimum inhibited lipolysis by the immobilized enzyme. Kinetic analysis of phosphatidylcholine-stabilized triglyceride emulsions revealed a significant decrease in immobilized enzyme K/sub m/ and an increase in V/sub max/ when the emulsion was supplemented with apoE. Distributing the immobilized lipase in clustered aggregates produced more lipolysis than when the same enzyme content was uniformly bound

  9. Mapping of low molecular weight heparins using reversed phase ion pair liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Li, Daoyuan; Chi, Lequan; Jin, Lan; Xu, Xiaohui; Du, Xuzhao; Ji, Shengli; Chi, Lianli

    2014-01-01

    Low molecular weight heparins (LMWHs) are structurally complex, highly sulfated and negatively charged, linear carbohydrate polymers prepared by chemical or enzymatic depolymerization of heparin. They are widely used as anticoagulant drugs possessing better bioavailability, longer half-life, and lower side effects than heparin. Comprehensive structure characterization of LMWHs is important for drug quality assurance, generic drug application, and new drug research and development. However, fully characterization of all oligosaccharide chains in LMWHs is not feasible for current available analytical technologies due to their structure complexity and heterogeneity. Fingerprinting profiling is an efficient way for LMWHs' characterization and comparison. In this work, we present a simple, sensitive, and powerful analytical approach for structural characterization of LMWHs. Two different LMWHs, enoxaparin and nadroparin, were analyzed using reversed phase ion pair electrospray ionization mass spectrometry (RPIP-ESI-MS). More than 200 components were identified, including major structures, minor structures, and process related impurities. This approach is robust for high resolution and complementary fingerprinting analysis of LMWHs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Comparison of digoxin concentration in plastic serum tubes with clot activator and heparinized plasma tubes.

    Science.gov (United States)

    Dukić, Lora; Simundić, Ana-Maria; Malogorski, Davorin

    2014-01-01

    Sample type recommended by the manufacturer for the digoxin Abbott assay is either serum collected in glass tubes or plasma (sodium heparin, lithium heparin, citrate, EDTA or oxalate as anticoagulant) collected in plastic tubes. In our hospital samples are collected in plastic tubes. Our hypothesis was that the serum sample collected in plastic serum tube can be used interchangeably with plasma sample for measurement of digoxin concentration. Our aim was verification of plastic serum tubes for determination of digoxin concentration. Concentration of digoxin was determined simultaneously in 26 venous blood plasma (plastic Vacuette, LH Lithium heparin) and serum (plastic Vacuette, Z Serum Clot activator; both Greiner Bio-One GmbH, Kremsmünster, Austria) samples, on Abbott AxSYM analyzer using the original Abbott Digoxin III assay (Abbott, Wiesbaden, Germany). Tube comparability was assessed using the Passing Bablok regression and Bland-Altman plot. Serum and plasma digoxin concentrations are comparable. Passing Bablok intercept (0.08 [95% CI = -0.10 to 0.20]) and slope (0.99 [95% CI = 0.92 to 1.11]) showed there is no constant or proportional error. Blood samples drawn in plastic serum tubes and plastic plasma tubes can be interchangeably used for determination of digoxin concentration.

  11. A new biocompatible delivery scaffold containing heparin and bone morphogenetic protein 2

    Directory of Open Access Journals (Sweden)

    Thanyaphoo Suphannee

    2016-09-01

    Full Text Available Silicon-substituted calcium phosphate (Si-CaP was developed in our laboratory as a biomaterial for delivery in bone tissue engineering. It was fabricated as a 3D-construct of scaffolds using chitosan-trisodium polyphosphate (TPP cross-linked networks. In this study, heparin was covalently bonded to the residual -NH2 groups of chitosan on the scaffold applying carbodiimide chemistry. Bonded heparin was not leached away from scaffold surfaces upon vigorous washing or extended storage. Recombinant human bone morphogenetic protein 2 (rhBMP-2 was bound to conjugated scaffolds by ionic interactions between the negatively charged SO42- clusters of heparin and positively charged amino acids of rhBMP-2. The resulting scaffolds were inspected for bone regenerative capacity by subcutaneous implanting in rats. Histological observation and mineralization assay were performed after 4 weeks of implantation. Results from both in vitro and in vivo experiments suggest the potential of the developed scaffolds for bone tissue engineering applications in the future.

  12. Heparin-Induced Thrombocytopenia Associated with Massive Intracardiac Thrombosis: A Case Report

    Directory of Open Access Journals (Sweden)

    Atheer Ahmed

    2012-01-01

    Full Text Available A 60-years old patient was admitted to a community hospital with septic arthritis. He was treated with antibiotics and subcutaneous unfractionated heparin (UH was used for venous thromboprophylaxis. After three days, he developed leg deep venous thrombosis and was treated with IV heparin. One day later, the patient developed pulmonary emboli, which was found using ventilation/perfusion scan. He was transferred to the University Hospital for further management. Upon arrival, antibiotic and intravenous UH were continued. Trans-Esophageal Echocardiogram showed a thrombus in the right atrium, a small portion of which extended to the left atrium through a patent foramen ovale. Another large thrombus was noted in the right ventricle, which extended to the pulmonary artery. Review of the patient’s medical records revealed a halving of his platelet count three days following the heparin administration. Therefore, HIT seemed very likely. Intravenous UH was stopped and an emergency thrombectomy was performed. ELISA testing of HIT antibodies came negative. This made HIT diagnosis unlikely and the patient received dalteparin. A week later, as the platelet count declined again, HIT antibodies’ testing using ELISA and C-14 serotonin release was repeated, and both assays were positive. Argatroban was restarted and the platelet count normalized.

  13. Thrombolytic treatment for acute ischemic cerebral stroke: intraarterial urokinase infusion vs. intravenous heparin and urokinase infusion

    International Nuclear Information System (INIS)

    Ko, Gi Young; Suh, Dae Chul; Lee, Jae Hong; Kim, Jun Hyoung; Choi, Choong Gon; Lee, Ho Kyu; Lee, Myoung Chong

    1996-01-01

    To evaluate the efficacy and limitation of intra-arterial urokinase (IAUK) infusion for treatment of acute cerebral stroke. Twenty-seven acute cerebral stroke patients treated with IAUK infusion within six hours of stroke onset were reviewed. All patients showed normal initial brain findings on CT. In 21 patients, urokinase(5-15 x 10 5 IU) was administered through a microcatheter placed into or proximal to occluded segment. Mechanical disruption of thrombus by guidewire was performed in 17 patients. Angiographic and clinical responses and complications after IAUK infusion, were evaluated and the results were compared with those of intravenous heparin(N=19) and urokinase infusion(N=19). Complete or partial angiographic recanalization of occluded segment was found in 18 patients (67%), and neurologic improvement was followed in 14 patients(52%). The degree of improvement on the stroke scale score after IAUK infusion was statistically more significant(p<0.05) than that shown after intravenous heparin and urokinase infusion. Complications after IAUK infusion were large(15%) and small amount intracerebral hemorrhage(15%), contrast leakage into brain parenchyma(11%), and gastrointestinal bleeding(4%). Between the IAVK and the intravenous urokinase infusion group, differences in extent and types of complications were statistically insignificant, but were significantly higher in those two groups than in the intravenous heparin infusion group. IAUK infusion may be effective for the treatment of acute cerebral stroke

  14. Photochemically synthesized heparin-based silver nanoparticles: an antimicrobial activity study

    Science.gov (United States)

    Rodriguez-Torres, Maria del Pilar; Acosta-Torres, Laura Susana; Díaz-Torres, Luis Armando

    2017-08-01

    The antimicrobial activity of silver nanoparticles has been extensively studied in the last years. Such nanoparticles constitute a potential and promising approach for the development of new antimicrobial systems especially due to the fact that several microorganisms are developing resistance to some already existing antimicrobial agents, therefore making antibacterial and antimicrobial studies on alternative materials necessary to overcome this issue. Silver nanoparticle concentration and size are determining factors on the antimicrobial activity of these nano systems. Heparin is a polysaccharide that belongs to the glycosaminoglycans (GAGs) family, molecules formed by a base disaccharide whose components are joined by a glycosidic linkage that is a repeating unit along their structure. It is highly sulfated making it a negatively charged material that is also widely used as an anticoagulant in Medicine because its biocompatibility besides it is also produced within the human body, specifically in the mast cells. Heparin alone possesses antimicrobial activity although it has not been studied very much in detail, it only has been demonstrated that it inhibits E. coli, P. aeruginosa, S. aureus and S. epidermidis, so taking this into account, this study is dedicated to assess UV photochemically-synthesized (λ=254 nm) heparin-based silver nanoparticles antimicrobial activity using the agar disk diffusion method complemented by the broth microdilution method to estimate de minimum inhibitory concentration (MIC), that is the lowest concentration at which an antimicrobial will inhibit visible growth of a microorganism. The strains used were the ones aforementioned to assess the antimicrobial activity degree these heparinbased nanoparticles exhibit.

  15. Heparin crisis 2008: a tipping point for increased FDA enforcement in the pharma sector?

    Science.gov (United States)

    Rosania, Larry

    2010-01-01

    Against a backdrop of steady deregulation, the pharmaceutical industry is increasingly outsourcing manufacturing, resulting in decentralized control of the global supply chain. Established products such as heparin have been held to outdated analytical standards. Ten million Americans receive heparin every year; Baxter International accounts for half of this market. In 2008, contamination of Baxter's heparin--sourced in China--resulted in about 350 adverse events and 150 deaths in the United States. In future, increasingly stringent FDA inspections and enforcement are expected for imported drugs and ingredients. More regional FDA offices will be set up overseas. FDA funding will likely be supplemented in future by user fees charged to importers. For newer products, companies will face pressure to adopt Quality by Design, with solid control of the global supply chain and a proactive focus on GMP. Older products will be held to modern standards. Long-term, imports of drugs and ingredients from developing markets will continue. This makes sense to companies from an economic standpoint, but protections will be essential to ensure that it is also justifiable from a public health perspective.

  16. Capillary electrophoresis of heparin and other glycosaminoglycans using a polyamine running electrolyte

    International Nuclear Information System (INIS)

    Loegel, Thomas N.; Trombley, John D.; Taylor, Richard T.; Danielson, Neil D.

    2012-01-01

    Highlights: ► Ethylenediamine is likely acting as an ion-pairing agent. ► Oversulfated chondroitin sulfate is last peak instead of first peak. ► There is about a factor of five improved detectability with a 12.5 min analysis time. ► Use of a 50 μm ID capillary is possible. - Abstract: This study involves the use of polyamines as potential resolving agents for the capillary electrophoresis (CE) of glycosaminoglycans (GAGs), specifically heparin, dermatan sulfate, chondroitin sulfate, over-sulfated chondroitin sulfate (OSCS), and hyaluronan. All of the compounds can be separated from each other with the exception of chondroitin sulfate and hyaluronan. Using optimization software, the final run conditions are found to be 200 mM ethylenediamine and 45.5 mM phosphate as the electrolyte with −14 V applied across a 50 μm ID × 24.5 cm fused silica capillary at 15 °C. The ion migration order, with OSCS as the last instead of the first peak, is in contrast to previous reports using either a high molarity TRIS or lithium phosphate run buffer with narrower bore capillaries. Total analysis time is 12. 5 min and the relative standard deviation of the heparin migration time is about 2.5% (n = 5). The interaction mechanism between selected polyamines and heparin is explored using conductivity measurements in addition to CE experiments to show that an ion-pairing mechanism is likely.

  17. Effect of combined topical heparin and steroid on corneal neovascularization in children.

    Science.gov (United States)

    Michels, Rike; Michels, Stephan; Kaminski, Stephan

    2012-01-01

    To demonstrate the effect of topical heparin combined with topical steroid on corneal neovascularization (CN) in children. Four children (5 eyes) with new-onset progressive CN in at least one eye received topical rimexolone or dexamethasone in combination with heparin until complete regression of CN was obtained. The regression of CN was documented by slit-lamp or anterior segment photography. All 5 eyes showed complete regression of CN within 5 months. An anti-angiogenic effect was found as early as 1 week after starting topical combination treatment. No ocular and systemic side effects were detected and treatment was well tolerated by all children. In the 3 eyes with involvement of the optical axis, symmetrical visual acuity was obtained by amblyopia treatment. Recurrence of the CN was detectable in 2 eyes at 1 and 6 months, respectively, after ending combination therapy. Both eyes responded favorably to re-treatment. Combination of topical heparin and steroid leads to rapid regression and complete inactivity of CN. This therapeutic approach is promising, especially in children with limited therapeutic alternatives and a high risk for amblyopia. Copyright 2012, SLACK Incorporated.

  18. Prediction of the oversulphated chondroitin sulphate contamination of unfractionated heparin by ATR-IR spectrophotometry.

    Science.gov (United States)

    Norwig, J; Beyer, T; Brinz, D; Holzgrabe, U; Diller, M; Manns, D

    2009-03-01

    The detection of a contamination of heparin with oversulphated chondroitin sulphate (OSCS) was first analysed in an unfractionated heparin batch supplied to the US API-market in April 2006. OSCS is a semi-synthetic derivative of the natural occuring glycosaminoglycan chondroitin sulphate. Moreover some spectroscopic characteristics of the substance overlap with those of heparin, so that the infrared (IR) spectra are visually difficult to distinguish whereas (1)H-NMR (Nuclear Magnetic Resonance) spectroscopy or capillary electrophoresis (CE) provides identification by a simple visual inspection of either the spectrum or the electropherogram respectively. However, applying special tools of Multivariate Data Analysis (MVA) to the IR spectra an identification of the contaminated samples is possible. In detail a rapid Attenuation Total Reflectance-Infrared (ATR-IR) measurement was selected, which does not require any sample preparation. The result (contaminated or not contaminated) is predicted within a few minutes. A method transfer to mobile ATR-IR spectrometers seems to be possible. The analysis is based on the fact that the fingerprint of the OSCS IR spectrum (1st derivative) complies with a theoretically calculated principal component in the MVA.

  19. Anti-tumor activity of a novel HS-mimetic-vascular endothelial growth factor binding small molecule.

    Directory of Open Access Journals (Sweden)

    Kazuyuki Sugahara

    Full Text Available The angiogenic process is controlled by variety of factors of which the vascular endothelial growth factor (VEGF pathway plays a major role. A series of heparan sulfate mimetic small molecules targeting VEGF/VEGFR pathway has been synthesized. Among them, compound 8 (2-butyl-5-chloro-3-(4-nitro-benzyl-3H-imidazole-4-carbaldehyde was identified as a significant binding molecule for the heparin-binding domain of VEGF, determined by high-throughput-surface plasmon resonance assay. The data predicted strong binding of compound 8 with VEGF which may prevent the binding of VEGF to its receptor. We compared the structure of compound 8 with heparan sulfate (HS, which have in common the functional ionic groups such as sulfate, nitro and carbaldehyde that can be located in similar positions of the disaccharide structure of HS. Molecular docking studies predicted that compound 8 binds at the heparin binding domain of VEGF through strong hydrogen bonding with Lys-30 and Gln-20 amino acid residues, and consistent with the prediction, compound 8 inhibited binding of VEGF to immobilized heparin. In vitro studies showed that compound 8 inhibits the VEGF-induced proliferation migration and tube formation of mouse vascular endothelial cells, and finally the invasion of a murine osteosarcoma cell line (LM8G7 which secrets high levels of VEGF. In vivo, these effects produce significant decrease of tumor burden in an experimental model of liver metastasis. Collectively, these data indicate that compound 8 may prevent tumor growth through a direct effect on tumor cell proliferation and by inhibition of endothelial cell migration and angiogenesis mediated by VEGF. In conclusion, compound 8 may normalize the tumor vasculature and microenvironment in tumors probably by inhibiting the binding of VEGF to its receptor.

  20. Structural model for the interaction of a designed Ankyrin Repeat Protein with the human epidermal growth factor receptor 2.

    Directory of Open Access Journals (Sweden)

    V Chandana Epa

    Full Text Available Designed Ankyrin Repeat Proteins are a class of novel binding proteins that can be selected and evolved to bind to targets with high affinity and specificity. We are interested in the DARPin H10-2-G3, which has been evolved to bind with very high affinity to the human epidermal growth factor receptor 2 (HER2. HER2 is found to be over-expressed in 30% of breast cancers, and is the target for the FDA-approved therapeutic monoclonal antibodies trastuzumab and pertuzumab and small molecule tyrosine kinase inhibitors. Here, we use computational macromolecular docking, coupled with several interface metrics such as shape complementarity, interaction energy, and electrostatic complementarity, to model the structure of the complex between the DARPin H10-2-G3 and HER2. We analyzed the interface between the two proteins and then validated the structural model by showing that selected HER2 point mutations at the putative interface with H10-2-G3 reduce the affinity of binding up to 100-fold without affecting the binding of trastuzumab. Comparisons made with a subsequently solved X-ray crystal structure of the complex yielded a backbone atom root mean square deviation of 0.84-1.14 Ångstroms. The study presented here demonstrates the capability of the computational techniques of structural bioinformatics in generating useful structural models of protein-protein interactions.