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Sample records for 2-hour urokinase regime

  1. Molecular-specific urokinase antibodies

    NASA Technical Reports Server (NTRS)

    Atassi, M. Zouhair (Inventor); Morrison, Dennis R. (Inventor)

    2009-01-01

    Antibodies have been developed against the different molecular forms of urokinase using synthetic peptides as immunogens. The peptides were synthesized specifically to represent those regions of the urokinase molecules which are exposed in the three-dimensional configuration of the molecule and are uniquely homologous to urokinase. Antibodies are directed against the lysine 158-isoleucine 159 peptide bond which is cleaved during activation from the single-chain (ScuPA) form to the bioactive double chain (54 KDa and 33 KDa) forms of urokinase and against the lysine 135 lysine 136 bond that is cleaved in the process of removing the alpha-chain from the 54 KDa form to produce the 33 KDa form of urokinase. These antibodies enable the direct measurement of the different molecular forms of urokinase from small samples of conditioned medium harvested from cell cultures.

  2. Development of immunoassays for human urokinase

    NASA Technical Reports Server (NTRS)

    Atassi, M. Zouhair

    1988-01-01

    Radioimmune assays (RIA) and enzyme linked immune assays for measurement of pro-urokinase and the two active forms of the enzyme were developed. Polyclonal and monoclonal antibodies, with desired specificities against preselected synthetic regions of urokinase (UK), were obtained by immunization with the respective synthetic peptides and used to develop RIA for zymogen and the two activated forms of UK.

  3. 29 CFR 2530.200b-2 - Hour of service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... MINIMUM STANDARDS FOR EMPLOYEE PENSION BENEFIT PLANS UNDER THE EMPLOYEE RETIREMENT INCOME SECURITY ACT OF 1974 RULES AND REGULATIONS FOR MINIMUM STANDARDS FOR EMPLOYEE PENSION BENEFIT PLANS Scope and General Provisions § 2530.200b-2 Hour of service. (a) General rule. An hour of service which must, as a minimum,...

  4. Quantitative method of measuring cancer cell urokinase and metastatic potential

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Inventor)

    1993-01-01

    The metastatic potential of tumors can be evaluated by the quantitative detection of urokinase and DNA. The cell sample selected for examination is analyzed for the presence of high levels of urokinase and abnormal DNA using analytical flow cytometry and digital image analysis. Other factors such as membrane associated urokinase, increased DNA synthesis rates and certain receptors can be used in the method for detection of potentially invasive tumors.

  5. Human Trials of a 2-Hour Prebreathe Protocol

    NASA Technical Reports Server (NTRS)

    Butler, Bruce D.; Vann, R. D.; Nishi, Ronald Y.; Gerth, W. A.; Beltran, E.; Conkin, J.; Schneider, Suzanne; Loftin, K. C.; Sullivan, Pat A.; Homick, Jerry L. (Technical Monitor)

    2000-01-01

    We evaluate 2-hour prebreathe protocols combining simulated microgravity and exercise during prebreathe with the objective of validating a protocol for use on International Space Station (ISS). The protocol was tested with four different exercise doses during prebreathe in a multi-center trial involving three laboratories. Subject selection, Doppler monitoring techniques for venous gas emboli (VGE), test termination criteria, and definitions of decompression sickness (DCS) were standardized in all laboratories. The Phase II protocol met the accept criteria for a prebreathe procedure for use by astronauts during assembly and maintenance of the ISS Dual-cycle ergometry or light exercise individually was not sufficient to protect against DCS at acceptable levels. The combination of both was successful.

  6. Antibodies Against Three Forms of Urokinase

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.; Atassi, M. Zouhair

    2007-01-01

    Antibodies that bind to preselected regions of the urokinase molecule have been developed. These antibodies can be used to measure small quantities of each of three molecular forms of urokinase that could be contained in microsamples or conditioned media harvested from cultures of mammalian cells. Previously available antibodies and assay techniques do not yield both clear distinctions among, and measurements of, all three forms. Urokinase is a zymogen that is synthesized in a single-chain form, called ScuPA, which is composed of 411 amino acid residues (see figure). ScuPA has very little enzyme activity, but it can be activated in two ways: (1) by cleavage of the peptide bond lysine 158/isoleucine 159 and the loss of lysine 158 to obtain the high molecular-weight (HMW) form of the enzyme or (2) by cleavage of the bond lysine 135/lysine 136 to obtain the low-molecular-weight (LMW) form of the enzyme. The antibodies in question were produced in mice and rabbits by use of peptides as immunogens. The peptides were selected to obtain antibodies that bind to regions of ScuPA that include the lysine 158/isoleucine 159 and the lysine 135/lysine 136 bonds. The antibodies include monoclonal and polyclonal ones that yield indications as to whether either of these bonds is intact. The polyclonal antibodies include ones that preferentially bind to the HMW or LMW forms of the urokinase molecule. The monoclonal antibodies include ones that discriminate between the ScuPA and the HMW form. A combination of these molecular-specific antibodies will enable simultaneous assays of the ScuPA, HMW, and LMW forms in the same specimen of culture medium.

  7. Increased Plasminogen Activator (Urokinase) in Tissue Culture After Fibrin Deposition

    PubMed Central

    Bernik, Maria B.

    1973-01-01

    Lysis of fibrin in tissue culture has been shown to be due to plasminogen activator identified immunologically as urokinase. The present study examines fibrinolytic events in culture, particularly mechanisms leading to increased urokinase levels and accelerated fibrinolysis. Deposition of fibrin on cells in culture was followed by a two- to six-fold increase in urokinase in the supernates and rapid disappearance of the fibrin. Investigation of factors that might be responsible for these events (including fibrin, fibrinogen, vasoactive stimuli, and the enzymes thrombin and plasmin) indicated that the enhanced urokinase yields were mediated through plasmin and thrombin. Study of the possible modes of action of thrombin and plasmin indicated that these enzymes are capable of acting on the cells themselves as well as on cell-produced material. The effect on cells was manifested by mitotic activity or, occasionally, cell injury and death. Although these effects influenced urokinase levels, enhanced yields were explained best by the action of enzymes on cellproduced material. Studies with plasmin and thrombin, and also trypsin, indicated that proteolytic enzymes may act in various ways—affect the stability of urokinase, interfere with inhibition of urokinase by naturally occurring inhibitor(s), and induce urokinase activity from inactive material. Plasma and thrombin appeared to act primarily through the latter mechanism. Inactive material, which gave rise to urokinase upon exposure to proteolytic enzymes and which may represent urokinase precursor, was found in cultures of kidney, lung, spleen, and thyroid. Urokinase in such inactive state appears to be readily accessible to activation by enzymes, particularly plasmin and thrombin, thus facilitating removal of fibrin and possibly also providing pathways to excessive fibrinolysis. PMID:4266421

  8. Inflight Exercise Regimen for the 2-Hour Prebreathe Protocol

    NASA Technical Reports Server (NTRS)

    Foster, Philip P.; Gernhardt, Michael L.; Woodruff, Kristin K.; Schneider, Susan M.; Homick, Jerry L. (Technical Monitor)

    2000-01-01

    A 10 min aerobic prebreathe exercise up to 75% V-O2(sub max) on a dual-cycle ergometer, included in the 2-hour prebreathe protocol, has been shown to dramatically reduce the incidence of decompression sickness (DCS) at altitude. In-flight only leg ergometry will be available. A balanced exercise was developed using surgical tubing with the ergometer on-orbit. We hypothesize that a 75% V02max workload, individually prescribed, would be achieved using a target heart rate to regulate the intensity of the arm exercise. VO2, heart rate (HR) / ECG, V-CO2 /V-O2, V(sub E), and V(sub T), and rate of perceived exertion (Borg scale) were measured in eleven healthy subjects who passed a US Air Force Class III Physical examination. A V-O2 peak test was performed to assess the sub-maximal exercise prescription. Two series of sub-maximal tests were performed: (1) leg ergometer/hand ergometer and (2) leg ergometer/surgical tubes. We found no significant differences (P > 0.05) in comparing the means for V-O2 and HR between the predicted and measured values during the final 4 minute-stage at "75% V-O2 workload" or between the two types of sub-maximal tests. The prescribed prebreathe sub-maximal exercise performed with flight certified surgical tubes was achieved using the target HR.

  9. Interaction of urokinase A chain with the receptor of human keratinocytes stimulates release of urokinase-like plasminogen activator

    SciTech Connect

    Fibbi, G.; Magnelli, L.; Pucci, M.; Del Rosso, M. )

    1990-03-01

    On the basis of a fibrinolytic assay with {sup 125}I-fibrin, zymography, and immunoprobing with anti-human urokinase antibody, the authors have observed that the in vitro established NCTC human keratinocyte cell line releases into the culture medium a 54,000-Da plasminogen activator which is indistinguishable from human urokinase. Only the early release following the washing of keratinocyte monolayers is accounted for by secretion of preformed enzyme, while late secretory events require the de novo synthesis of urokinase. The released enzyme can interact by autocriny with its own receptor present on keratinocytes. The addition to the keratinocyte culture medium of the urokinase A chain can stimulate a concentration-dependent urokinase oversecretion, which is not paralleled by oversecretion of plasminogen activator inhibitor-1. Since stimulation of urokinase production can be obtained by an A chain concentration which was previously shown to be efficient in inducing keratinocyte mobilization in an in vitro migration model system, they hypothesize that this mechanism may be important in vivo during the process of wound repair.

  10. Fluorescent-Antibody Measurement Of Cancer-Cell Urokinase

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.

    1993-01-01

    Combination of laboratory techniques provides measurements of amounts of urokinase in and between normal and cancer cells. Includes use of fluorescent antibodies specific against different forms of urokinase-type plasminogen activator, (uPA), fluorescence microscopy, quantitative analysis of images of sections of tumor tissue, and flow cytometry of different uPA's and deoxyribonucleic acid (DNA) found in suspended-tumor-cell preparations. Measurements provide statistical method for indicating or predicting metastatic potentials of some invasive tumors. Assessments of metastatic potentials based on such measurements used in determining appropriate follow-up procedures after surgical removal of tumors.

  11. Urokinase-controlled tumor penetrating peptide.

    PubMed

    Braun, Gary B; Sugahara, Kazuki N; Yu, Olivia M; Kotamraju, Venkata Ramana; Mölder, Tarmo; Lowy, Andrew M; Ruoslahti, Erkki; Teesalu, Tambet

    2016-06-28

    Tumor penetrating peptides contain a cryptic (R/K)XX(R/K) CendR element that must be C-terminally exposed to trigger neuropilin-1 (NRP-1) binding, cellular internalization and malignant tissue penetration. The specific proteases that are involved in processing of tumor penetrating peptides identified using phage display are not known. Here we design de novo a tumor-penetrating peptide based on consensus cleavage motif of urokinase-type plasminogen activator (uPA). We expressed the peptide, uCendR (RPARSGR↓SAGGSVA, ↓ shows cleavage site), on phage or coated it onto silver nanoparticles and showed that it is cleaved by uPA, and that the cleavage triggers binding to recombinant NRP-1 and to NPR-1-expressing cells. Upon systemic administration to mice bearing uPA-overexpressing breast tumors, FAM-labeled uCendR peptide and uCendR-coated nanoparticles preferentially accumulated in tumor tissue. We also show that uCendR phage internalization into cultured cancer cells and its penetration in explants of murine tumors and clinical tumor explants can be potentiated by combining the uCendR peptide with tumor-homing module, CRGDC. Our work demonstrates the feasibility of designing tumor-penetrating peptides that are activated by a specific tumor protease. As upregulation of protease expression is one of the hallmarks of cancer, and numerous tumor proteases have substrate specificities compatible with proteolytic unmasking of cryptic CendR motifs, the strategy described here may provide a generic approach for designing proteolytically-actuated peptides for tumor-penetrative payload delivery. PMID:27106816

  12. A comparison between 24-hour and 2-hour urine collection for the determination of proteinuria.

    PubMed

    Somanathan, N; Farrell, T; Galimberti, A

    2003-07-01

    Proteinuria is one of the fundamental criteria for the diagnosis of pre-eclampsia with quantitative assessment based on the 24-hour urine protein estimation as the gold standard. This study was undertaken to determine whether a 2-hour protein estimation correlated with that of a formal 24-hour collection. Thirty women with proteinuric hypertension were recruited. There was significant correlation between the 2-hour and 24-hour urine protein levels (Pearson's correlation coefficient 0.76 (P 0.000). A positive 2-hour test was associated more closely with significant levels of 24-hour proteinuria than dipstick analysis alone. We conclude from this study that a random 2-hour sample could be used for the initial assessment of proteinuria and so avoid the delay associated with 24-hour quantification of urinary protein. PMID:12881076

  13. Signaling through urokinase and urokinase receptor in lung cancer cells requires interactions with beta1 integrins.

    PubMed

    Tang, Chi-Hui; Hill, Marla L; Brumwell, Alexis N; Chapman, Harold A; Wei, Ying

    2008-11-15

    The urokinase receptor (uPAR) is upregulated upon tumor cell invasion and correlates with poor lung cancer survival. Although a cis-interaction with integrins has been ascribed to uPAR, whether this interaction alone is critical to urokinase (uPA)- and uPAR-dependent signaling and tumor promotion is unclear. Here we report the functional consequences of point mutations of uPAR (H249A-D262A) that eliminate beta1 integrin interactions but maintain uPA binding, vitronectin attachment and association with alphaV integrins, caveolin and epidermal growth factor receptor. Disruption of uPAR interactions with beta1 integrins recapitulated previously reported findings with beta1-integrin-derived peptides that attenuated matrix-dependent ERK activation, MMP expression and in vitro migration by human lung adenocarcinoma cell lines. The uPAR mutant cells acquired enhanced capacity to adhere to vitronectin via uPAR-alphaVbeta5-integrin, rather than through the uPAR-alpha3beta1-integrin complex and they were unable to initiate uPA signaling to activate ERK, Akt or Stat1. In an orthotopic lung cancer model, uPAR mutant cells exhibited reduced tumor size compared with cells expressing wild-type uPAR. Taken together, the results indicate that uPAR-beta1-integrin interactions are essential to signals induced by integrin matrix ligands or uPA that support lung cancer cell invasion in vitro and progression in vivo. PMID:18940913

  14. Urokinase production by electrophoretically separated cultured human embryonic kidney cells

    NASA Technical Reports Server (NTRS)

    Kunze, M. E.; Plank, L. D.; Giranda, V.; Sedor, K.; Todd, P. W.

    1985-01-01

    Urokinase is a plasminogen activator found in urine. Relatively pure preparations have been tested in Europe, Japan and the United States for the treatment of deep vein thrombosis and other dangerous blood clots. Human embryonic kidney cell cultures have been found to produce urokinase at much higher concentrations, but less than 5% of the cells in typical cultures are producers. Since human diploid cells become senescent in culture the selection of clones derived from single cells will not provide enough material to be useful, so a bulk purification method is needed for the isolation of urokinase producing cell populations. Preparative cell electrophoresis was chosen as the method, since evidence exists that human embryonic cell cultures are richly heterogeneous with respect to electrophoretic mobility, and preliminary electrophoretic separations on the Apollo-Soyuz space flight produced cell populations that were rich in urokinase production. Similarly, erythropoietin is useful in the treatment of certain anemias and is a kidney cell duct, and electrophoretically enriched cell populations producing this product have been reported. Thus, there is a clear need for diploid human cells that produce these products, and there is evidence that such cells should be separable by free-flow cell electrophoresis.

  15. Soluble Urokinase Receptor and Chronic Kidney Disease

    PubMed Central

    Hayek, Salim S.; Sever, Sanja; Ko, Yi-An; Trachtman, Howard; Awad, Mosaab; Wadhwani, Shikha; Altintas, Mehmet M.; Wei, Changli; Hotton, Anna L.; French, Audrey L.; Sperling, Laurence S.; Lerakis, Stamatios; Quyyumi, Arshed A.; Reiser, Jochen

    2015-01-01

    BACKGROUND Relatively high plasma levels of soluble urokinase-type plasminogen activator receptor (suPAR) have been associated with focal segmental glomerulosclerosis and poor clinical outcomes in patients with various conditions. It is unknown whether elevated suPAR levels in patients with normal kidney function are associated with future decline in the estimated glomerular filtration rate (eGFR) and with incident chronic kidney disease. METHODS We measured plasma suPAR levels in 3683 persons enrolled in the Emory Cardiovascular Biobank (mean age, 63 years; 65% men; median suPAR level, 3040 pg per milliliter) and determined renal function at enrollment and at subsequent visits in 2292 persons. The relationship between suPAR levels and the eGFR at baseline, the change in the eGFR over time, and the development of chronic kidney disease (eGFR <60 ml per minute per 1.73 m2 of body-surface area) were analyzed with the use of linear mixed models and Cox regression after adjustment for demographic and clinical variables. RESULTS A higher suPAR level at baseline was associated with a greater decline in the eGFR during follow-up; the annual change in the eGFR was −0.9 ml per minute per 1.73 m2 among participants in the lowest quartile of suPAR levels as compared with −4.2 ml per minute per 1.73 m2 among participants in the highest quartile (P<0.001). The 921 participants with a normal eGFR (≥90 ml per minute per 1.73 m2) at baseline had the largest suPAR-related decline in the eGFR. In 1335 participants with a baseline eGFR of at least 60 ml per minute per 1.73 m2, the risk of progression to chronic kidney disease in the highest quartile of suPAR levels was 3.13 times as high (95% confidence interval, 2.11 to 4.65) as that in the lowest quartile. CONCLUSIONS An elevated level of suPAR was independently associated with incident chronic kidney disease and an accelerated decline in the eGFR in the groups studied. (Funded by the Abraham J. and Phyllis Katz Foundation

  16. Urokinase and the intestinal mucosa: evidence for a role in epithelial cell turnover

    PubMed Central

    Gibson, P; Birchall, I; Rosella, O; Albert, V; Finch, C; Barkla, D; Young, G

    1998-01-01

    Background—The functions of urokinase in intestinal epithelia are unknown. 
Aims—To determine the relation of urokinase expressed by intestinal epithelial cells to their position in the crypt-villus/surface axis and of mucosal urokinase activity to epithelial proliferative kinetics in the distal colon. 
Methods—Urokinase expression was examined immunohistochemically in human intestinal mucosa. Urokinase activity was measured colorimetrically in epithelial cells isolated sequentially from the crypt-villus axis of the rat small intestine. In separate experiments, urokinase activity and epithelial kinetics (measured stathmokinetically) were measured in homogenates of distal colonic mucosa of 14 groups of eight rats fed diets known to alter epithelial turnover. 
Results—From the crypt base, an ascending gradient of expression and activity of urokinase was associated with the epithelial cells. Median mucosal urokinase activities in each of the dietary groups of rats correlated positively with autologous median number of metaphase arrests per crypt (r=0.68; p<0.005) and per 100 crypt cells (r=0.75; p<0.001), but not with crypt column height. 
Conclusions—Localisation of an enzyme capable of leading to digestion of cell substratum in the region where cells are loosely attached to their basement membrane, and the association of its activity with indexes of cell turnover, suggest a role for urokinase in facilitating epithelial cell loss in the intestine. 

 Keywords: urokinase; intestinal epithelium; colon; epithelial proliferation PMID:9824347

  17. Immunohistochemical Detection of Urokinase Plasminogen Activator and Urokinase Plasminogen Activator Receptor in Canine Vascular Endothelial Tumours.

    PubMed

    Anwar, Sh; Yanai, T; Sakai, H

    2015-11-01

    Immunohistochemistry was used to assess the expression of urokinase plasminogen activator (uPA) and uPA receptor (uPAR) in 57 canine primary haemangiosarcomas (HSAs), 26 canine cutaneous haemangiomas (HAs) and in control sections of canine cutaneous granulation tissue. The correlation between uPA/uPAR expression and the Ki67 labelling index (LI) was estimated in the HSA and HA tissues. uPA was expressed by 73.2% and 75.0% of splenic HSAs and non-splenic HSAs, respectively. All HSA tissues tested expressed uPAR. Expression of both molecules was significantly higher in HSAs than in cutaneous HAs (3.8% for uPA and 30.7% for uPAR). The average Ki67 LI of the uPA(+)/uPAR(+) HSAs was significantly higher than that of uPA(-)/uPAR(+) HSAs and HA tissues (mean ± SDs 32.8 ± 15.3, 15.2 ± 7.2 and 2.1 ± 0.7, respectively; P <0.05). These results suggest that uPA and uPAR play a significant role in the malignant proliferation of canine HSA, regardless of the primary origin of the tumour. PMID:26286429

  18. Characterization of urokinase receptor expression by human placental trophoblasts.

    PubMed

    Zini, J M; Murray, S C; Graham, C H; Lala, P K; Karikó, K; Barnathan, E S; Mazar, A; Henkin, J; Cines, D B; McCrae, K R

    1992-06-01

    The processes of implantation and placentation are both dependent on the invasion and remodeling of the uterine endometrium and vasculature by trophoblasts. Because the secretion and autocrine binding of urokinase (uPA) appears to be a common mechanism used by cells to facilitate plasmin-dependent tissue invasion, we measured the production of uPA and expression of uPA receptors by trophoblasts. Prourokinase bound specifically, reversibly, and with high affinity to cultured trophoblasts, via the uPA epidermal growth factor-like domain. Trophoblasts derived from two first-trimester placentae bound more prourokinase than cells isolated from term placentae. Furthermore, in vitro differentiation of cultured cytotrophoblasts into syncytiotrophoblasts was associated with diminished expression of urokinase receptors and a parallel decrease in the cellular content of uPA receptor mRNA. Trophoblasts also secreted prourokinase and plasminogen activator inhibitors types 1 and 2 (PAI-1 and PAI-2). Although prourokinase was secreted in amounts sufficient to endogenously saturate trophoblast uPA receptors, trophoblasts secreted greater amounts of PAI-1 and PAI-2 than uPA, and no net plasminogen activator activity was detected in trophoblast conditioned medium. In contrast, plasminogen added directly to cultured trophoblasts was readily converted to plasmin. Although the invasion and remodeling of uterine tissues by trophoblasts is a complex process dependent on several proteases of varying specificity, our findings suggest that the expression and modulation of urokinase receptors on the trophoblast cell surface may play an important role in this process. PMID:1316787

  19. Purification of urokinase by combined cation exchanger and affinity chromatographic cartridges.

    PubMed

    Hou, K C; Zaniewski, R

    1990-02-23

    Crude urokinase from human urine processed through foam flotation and ammonium sulfate precipitation containing 720 National Health Institute Committee on Thrombolytic Agents U/mg activity was purified by an SP cation exchanger followed by a zinc-chelated affinity chromatographic cartridge. The cartridges were of a radial-flow type formed by using acrylic and cellulose composite matrices. The high rigidity of the matrix structure permits fast flow of protein solutions (liters per minute) and thus allows processing of a large volume of crude urokinase under low operating pressures. A greater than six-fold increase in specific enzyme activity of urokinase was achieved by adsorbing and eluting 1 l of a 3 mg/ml crude urokinase solution on an SP cartridge. The eluent was further purified by passing through a zinc-chelated affinity cartridge to achieve greater than a eighteen-fold increase in urokinase specific activity. This report demonstrates the combined use of a cation exchanger with zinc-chelated chromatographic cartridges in purifying urokinase on a relatively large scale. The relationship between the amount of zinc chelated in the matrix to its effect on urokinase purification is also discussed. PMID:2329161

  20. Single-chain urokinase in empyema induced by Pasturella multocida.

    PubMed

    Idell, Steven; Jun Na, Moon; Liao, Huai; Gazar, A E; Drake, Wonder; Lane, Kirk B; Koenig, Kathy; Komissarov, Andrey; Tucker, Torry; Light, Richard W

    2009-10-01

    Intrapleural fibrin deposition and subsequent fibrosis characterize evolving empyema and contribute to the morbidity associated with this condition. Single-chain urokinase (scuPA) is proenzyme form of the urokinase plasminogen activator, which has recently been shown to effectively clear intrapleural loculation in tetracycline-induced pleurodesis in rabbits. The authors therefore hypothesized that scuPA could likewise improve intrapleural injury associated with empyema. The authors used a rabbit model of empyema induced by intrapleural administration of Pasturella multocida to test this hypothesis and determined the effects of intrapleural scuPA on pleural fluids indices of inflammation and intrapleural fibrosis. The authors found that intrapleural administration of scuPA was well tolerated, generated readily detectable fibrinolytic activity in the empyema fluids and did not induce intrapleural or systemic bleeding. Pleural fluid volume, intrapleural protein, and D-dimer concentrations were increased at 24 and 48 hours (P < .01, respectively) after induction of empyema. Intrapleural loculation did not occur in the scuPA- or vehicle control-treated animals and there was no significant change in the pleural empyema or thickening scores. These findings confirm that intrapleural scuPA generates fibrinolysis in empyema fluids but does not alter fibrotic repair at the pleural surface or the intensity of intrapleural inflammation in this empyema model. PMID:19895321

  1. Clinical study of urokinase-bound fibrocollagenous tubes.

    PubMed

    Senatore, F; Bernath, F; Meisner, K

    1986-02-01

    Dacron-reinforced fibrocollagenous tubes (FCT) were synthesized from canine mongrels using the mandril-rod technique in order to develop a small diameter (i.e., 4 mm i.d.) vascular graft. They were rendered fibrinolytic by immobilizing urokinase on to the inner surface of the tubes. Urokinase-bound fibrocollagenous tubes (UK-FCT), control FCTs (i.e., no bound enzyme), Perloff grafts (Dr. Perloff, Department of Surgery, University Medical Center, Sidney Australia, has developed a mandril-derived collagenous tube from goats. Samples were implanted for comparative purposes.) and autogeneous saphenous veins, were interposed in the carotid or femoral artery in chronic studies involving 21 canine mongrels. On the basis of Doppler auscultation and palpation, the UK-FCTs were statistically more patent than other candidate prostheses. Fibrin degradation product (FDP) increased in the dogs' systemic circulation with a postoperative peak of 5 days. The host's increase in fibrinolytic activity was shown to be local to the anastamosis. A carotid arterial extracorporeal shunt was designed to evaluate acute patency. Results indicated a rapid thrombosis but no platlet or fibrin adherence to the graft surface was observed, as evidenced by scanning electron microscopy. PMID:2937788

  2. Nuclear translocation of urokinase-type plasminogen activator.

    PubMed

    Stepanova, Victoria; Lebedeva, Tatiana; Kuo, Alice; Yarovoi, Serge; Tkachuk, Sergei; Zaitsev, Sergei; Bdeir, Khalil; Dumler, Inna; Marks, Michael S; Parfyonova, Yelena; Tkachuk, Vsevolod A; Higazi, Abd Al-Roof; Cines, Douglas B

    2008-07-01

    Urokinase-type plasminogen activator (uPA) participates in diverse (patho)physiological processes through intracellular signaling events that affect cell adhesion, migration, and proliferation, although the mechanisms by which these occur are only partially understood. Here we report that upon cell binding and internalization, single-chain uPA (scuPA) translocates to the nucleus within minutes. Nuclear translocation does not involve proteolytic activation or degradation of scuPA. Neither the urokinase receptor (uPAR) nor the low-density lipoprotein-related receptor (LRP) is required for nuclear targeting. Rather, translocation involves the binding of scuPA to the nucleocytoplasmic shuttle protein nucleolin through a region containing the kringle domain. RNA interference and mutational analysis demonstrate that nucleolin is required for the nuclear transport of scuPA. Furthermore, nucleolin is required for the induction smooth muscle alpha-actin (alpha-SMA) by scuPA. These data reveal a novel pathway by which uPA is rapidly translocated to the nucleus where it might participate in regulating gene expression. PMID:18337556

  3. Operational Implementation of a 2-Hour Prebreathe Protocol for International Space Station

    NASA Technical Reports Server (NTRS)

    Waligora, James M.; Conkin, J.; Foster, P. P.; Schneider, S.; Loftin, Karin C.; Gernhardt, Michael L.; Vann, R.

    2000-01-01

    Procedures, equipment, and analytical techniques were developed to implement the ground tested 2-hour protocol in-flight operations. The methods are: 1) The flight protocol incorporates additional safety margin over the ground tested protocol. This includes up to 20 min of additional time on enriched O2 during suit purge and pressure check, increased duration of extravehicular activity (EVA) preparation exercise during O2 prebreathing (up to 90 min vs; the tested 24 min), and reduced rates of depressurization. The ground test observations were combined with model projections of the conservative measures (using statistical models from Duke University and NASA JSQ to bound the risk of Type I and Type II decompression sickness (DCS). 2) An inflight exercise device using the in-flight ergometer and elastic tubes for upper body exercise was developed to replicate the dual cycle exercise in the ground trials. 3) A new in-flight breathing system was developed and man-tested. 4) A process to monitor inflight experience with the protocol, including the use of an in-suit Doppler bubble monitor when available, was developed. The results are: 1) The model projections of the conservative factors of the operational protocol were shown to reduce the risk of DCS to levels consistent with the observations of no DCS to date in the shuttle program. 2) Cross over trials of the dual cycle ergometer used in ground tests and the in-flight exercise system verified that02consumption and the % division of work between upper and lower body was not significantly different at the p= 0.05 level. 3) The in-flight breathing system was demonstrated to support work rates generating 75% O2(max) in 95 percentile subjects. 4) An in-flight monitoring plan with acceptance criteria was put in place for the 2-hour prebreathe protocol. And the conclusions are: The 2-hour protocol has been approved for flight, and all implementation efforts are in place to allow use of the protocol as early as flight ISS 7A

  4. Structural investigations of recombinant urokinase growth factor-like domain.

    PubMed

    Beloglazova, I B; Beabealashvilli, R Sh; Gursky, Ya G; Bocharov, E V; Mineev, K S; Parfenova, E V; Tkachuk, V A

    2013-05-01

    Urokinase-type plasminogen activator (uPA) is a serine protease that converts the plasminogen zymogen into the enzymatically active plasmin. uPA is synthesized and secreted as the single-chain molecule (scuPA) composed of an N-terminal domain (GFD) and kringle (KD) and C-terminal proteolytic (PD) domains. Earlier, the structure of ATF (which consists of GFD and KD) was solved by NMR (A. P. Hansen et al. (1994) Biochemistry, 33, 4847-4864) and by X-ray crystallography alone and in a complex with the soluble form of the urokinase receptor (uPAR, CD87) lacking GPI (C. Barinka et al. (2006) J. Mol. Biol., 363, 482-495). According to these data, GFD contains two β-sheet regions oriented perpendicularly to each other. The area in the GFD responsible for binding to uPAR is localized in the flexible Ω-loop, which consists of seven amino acid residues connecting two strings of antiparallel β-sheet. It was shown by site-directed mutagenesis that shortening of the Ω-loop length by one amino acid residue leads to the inability of GFD to bind to uPAR (V. Magdolen et al. (1996) Eur. J. Biochem., 237, 743-751). Here we show that, in contrast to the above-mentioned studies, we found no sign of the β-sheet regions in GFD in our uPA preparations either free or in a complex with uPAR. The GFD seems to be a rather flexible and unstructured domain, demonstrating in spite of its apparent flexibility highly specific interaction with uPAR both in vitro and in cell culture experiments. Circular dichroism, tryptophan fluorescence during thermal denaturation of the protein, and heteronuclear NMR spectroscopy of ¹⁵N/¹³C-labeled ATF both free and in complex with urokinase receptor were used to judge the secondary structure of GFD of uPA. PMID:23848154

  5. Dialysis Access Graft Thrombolysis: Randomized Study of Pulse-Spray Versus Continuous Urokinase Infusion

    SciTech Connect

    Goodwin, Scott C.; Arora, Lokesh C.; Razavi, Mahmood K.; Sayre, James; McNamara, Thomas O.; Yoon, Chun

    1998-03-15

    Purpose: To compare pulse-spray to continuous-infusion thrombolysis with high-dose urokinase in thrombosed dialysis access grafts. Methods: A prospective randomized controlled trial was performed. From August 1992 to September 1993, 30 thrombosed polytetrafluoroethylene (PTFE) grafts in 24 patients were included, 15 grafts in each group. The success of thrombolysis, mean time to thrombolysis, mean urokinase dose, and 60-day patency rate were evaluated. Results: In the pulse-spray group, the mean time to thrombolysis was 72 min with a mean urokinase dose of 560,000 U. The 60-day patency rate was 71%. In the continuous-infusion group, the mean infusion time to thrombolysis was 55 min with a mean dose of 479,000 U. The 60-day patency rate was 73%. Conclusion: No statistically significant difference was found between the two techniques in the mean time to thrombolysis, the mean urokinase dose used, or the 60-day patency rate.

  6. Urokinase receptor is a multifunctional protein: influence of receptor occupancy on macrophage gene expression.

    PubMed Central

    Rao, N K; Shi, G P; Chapman, H A

    1995-01-01

    Binding of urokinase to the glycolipid-anchored urokinase receptor (uPAR) has been implicated in macrophage differentiation. However, no biochemical markers of differentiation have yet been directly linked to uPAR occupancy. As extensive changes in proteolytic profile characterize monocytic differentiation, we have examined the role of uPAR occupancy on protease expression by differentiating phagocytes. Antibodies to either urokinase or to uPAR that prevent receptor binding inhibited induction of cathepsin B in cultured monocytes and both cathepsin B and 92-kD gelatinase mRNA and protein in phorbol diester-stimulated myeloid cells. Mannosamine, an inhibitor of glycolipid anchor assembly, also blocked protease expression. Anti-catalytic urokinase antibodies, excess inactive urokinase, or aprotinin had no effect, indicating that receptor occupancy per se regulated protease expression. Antibodies to the integrins CD11a and CD29 or to the glycolipid-anchored proteins CD14 and CD55 also had no effect. Protease induction was independent of matrix attachment. Antibodies to urokinase or uPAR affected neither the decrease in cathepsin G nor the increase in tumor necrosis factor-alpha in phorbol ester-stimulated cells. These data establish that uPAR is a multifunctional receptor, not only promoting pericellular proteolysis and matrix attachment, but also effecting cysteine- and metallo-protease expression during macrophage differentiation. Images PMID:7615819

  7. Urokinase and type I plasminogen activator inhibitor production by normal human hepatocytes: modulation by inflammatory agents.

    PubMed

    Busso, N; Nicodeme, E; Chesne, C; Guillouzo, A; Belin, D; Hyafil, F

    1994-07-01

    We examined the effects of inflammatory cytokines (interleukin-1 beta, tumor necrosis factor-alpha and transforming growth factor-beta) on the plasminogen activator system (urokinase, tissue-type plasminogen activator, type 1 plasminogen activator inhibitor) in primary cultures of human hepatocytes. We show that interleukin-1 beta and tumor necrosis factor-alpha increase urokinase-type plasminogen activator production, reinforcing the concept that increased urokinase production is associated with inflammatory processes. By contrast, the same agents (i.e., interleukin-1 beta and tumor necrosis factor-alpha) do not stimulate plasminogen activator inhibitor type 1 production. This latter observation rules out hepatocytes as a major cellular source of plasmatic plasminogen activator inhibitor type 1 during acute-phase-related responses. Among the inflammatory agents used, transforming growth factor-beta was found to be the most effective modulator of both urokinase-type plasminogen activator and plasminogen activator inhibitor type 1, inducing severalfold increases of activity of urokinase-type plasminogen activator, antigen and the corresponding mRNA and increasing plasminogen activator inhibitor type 1 antigen and mRNA levels. Urokinase-type plasminogen activator and plasminogen activator inhibitor type 1 modulation by transforming growth factor-beta may play a critical role in hepatic pathophysiology. PMID:8020888

  8. Thrombolytic Therapy Using Urokinase for Management of Central Venous Catheter Thrombosis

    PubMed Central

    Son, Jung Tack; Min, Sun Young; Kim, Jae Il; Choi, Pyong Wha; Heo, Tae Gil; Lee, Myung Soo; Kim, Chul-Nam; Kim, Hong-Yong; Yi, Seong Yoon; Lee, Hye Ran; Roh, Young-Nam

    2014-01-01

    Purpose: The management of central venous catheters (CVCs) and catheter thrombosis vary among centers, and the efficacy of the methods of management of catheter thrombosis in CVCs is rarely reported. We investigated the efficacy of bedside thrombolysis with urokinase for the management of catheter thrombosis. Materials and Methods: We retrospectively reviewed data from patients who had undergone CVC insertion by a single surgeon in a single center between April 2012 and June 2014. We used a protocol for the management of CVCs and when catheter thrombosis was confirmed, 5,000 U urokinase was infused into the catheter. Results: A total of 137 CVCs were inserted in 126 patients. The most common catheter-related complication was thrombosis (12, 8.8%) followed by infection (8, 5.8%). Nine of the 12 patients (75%) with catheter thrombosis were recanalized successfully with urokinase. The rate of CVC recanalization was higher in the peripherally inserted central catheter (PICC) group (87.5%) than the chemoport group (50%). Reintervention for catheter-related thrombosis was needed in only 2.2% of patients when thrombolytic therapy using urokinase was applied. Age <60 years (P=0.035), PICC group (P=0.037) and location of the catheter tip above the superior vena cava (P=0.044) were confirmed as independent risk factors for catheter thrombosis. Conclusion: Thrombolysis therapy using urokinase could successfully manage CVC thrombosis. Reintervention was rarely needed when a protocol using urokinase was applied for the management of CVC thromboses. PMID:26217634

  9. Rationale for monitoring cyclosporine concentration at 2 hours after administration in infants posttransplantation.

    PubMed

    Furlan, V; Lykavieris, P; Maubert, M A; Habes, D; Debray, D

    2009-10-01

    Therapeutic drug monitoring is critical to avoid overimmunosuppression or underimmunosuppression in young pediatric transplant recipients. The objective of this study was to examine cyclosporine (CsA) trough (C0) and 2-hour post-dose (C2) concentrations in the early period after liver transplantation (OLT) to determine whether CsA C2 monitoring is justified. Seventeen infants younger than 2 years treated with CsA (Neoral) were monitored at C0. The biopsy-proved acute rejection rate was 65% at 3 months post-OLT. No correlation was observed between values at C0 and C2. Poor absorption of CsA was observed in most infants during the first 2 weeks post-OLT, as well as interindividual variability in CsA clearance. Exposure to CsA could not be estimated using either C0 or C2 determinations in the early post-OLT period. As a marker of poor absorption, C2 is useful but does not indicate delayed or rapid clearance of drug without simultaneous measurement of concentration at C0. We suggest the use of both C0 and C2 monitoring, or AUC monitoring on an individual basis during at least the first 2 weeks post-OLT. PMID:19857744

  10. Application of Molecular Modeling to Urokinase Inhibitors Development

    PubMed Central

    Sulimov, V. B.; Katkova, E. V.; Oferkin, I. V.; Sulimov, A. V.; Romanov, A. N.; Roschin, A. I.; Beloglazova, I. B.; Plekhanova, O. S.; Tkachuk, V. A.; Sadovnichiy, V. A.

    2014-01-01

    Urokinase-type plasminogen activator (uPA) plays an important role in the regulation of diverse physiologic and pathologic processes. Experimental research has shown that elevated uPA expression is associated with cancer progression, metastasis, and shortened survival in patients, whereas suppression of proteolytic activity of uPA leads to evident decrease of metastasis. Therefore, uPA has been considered as a promising molecular target for development of anticancer drugs. The present study sets out to develop the new selective uPA inhibitors using computer-aided structural based drug design methods. Investigation involves the following stages: computer modeling of the protein active site, development and validation of computer molecular modeling methods: docking (SOL program), postprocessing (DISCORE program), direct generalized docking (FLM program), and the application of the quantum chemical calculations (MOPAC package), search of uPA inhibitors among molecules from databases of ready-made compounds to find new uPA inhibitors, and design of new chemical structures and their optimization and experimental examination. On the basis of known uPA inhibitors and modeling results, 18 new compounds have been designed, calculated using programs mentioned above, synthesized, and tested in vitro. Eight of them display inhibitory activity and two of them display activity about 10 μM. PMID:24967388

  11. Secretion of macrophage urokinase plasminogen activator is dependent on proteoglycans.

    PubMed

    Pejler, Gunnar; Winberg, Jan-Olof; Vuong, Tram T; Henningsson, Frida; Uhlin-Hansen, Lars; Kimata, Koji; Kolset, Svein O

    2003-10-01

    The importance of proteoglycans for secretion of proteolytic enzymes was studied in the murine macrophage cell line J774. Untreated or 4beta-phorbol 12-myristate 13-acetate (PMA)-stimulated macrophages were treated with hexyl-beta-d-thioxyloside to interfere with the attachment of glycosaminoglycan chains to their respective protein cores. Activation of the J774 macrophages with PMA resulted in increased secretion of trypsin-like serine proteinase activity. This activity was completely inhibited by plasminogen activator inhibitor 1 and by amiloride, identifying the activity as urokinase plasminogen activator (uPA). Treatment of both the unstimulated or PMA-stimulated macrophages with xyloside resulted in decreased uPA activity and Western blotting analysis revealed an almost complete absence of secreted uPA protein after xyloside treatment of either control- or PMA-treated cells. Zymography analyses with gels containing both gelatin and plasminogen confirmed these findings. The xyloside treatment did not reduce the mRNA levels for uPA, indicating that the effect was at the post-translational level. Treatment of the macrophages with xylosides did also reduce the levels of secreted matrix metalloproteinase 9. Taken together, these findings indicate a role for proteoglycans in the secretion of uPA and MMP-9. PMID:14511379

  12. Involvement of the Soluble Urokinase Receptor in Chondrosarcoma Cell Mobilization

    PubMed Central

    Bifulco, Katia; Longanesi-Cattani, Immacolata; Masucci, Maria Teresa; De Chiara, Annarosaria; Fazioli, Flavio; Di Carluccio, Gioconda; Pirozzi, Giuseppe; Gallo, Michele; La Rocca, Antonello; Apice, Gaetano; Rocco, Gaetano; Carriero, Maria Vincenza

    2011-01-01

    High levels of urokinase receptor (uPAR) in tissue and serum of patients with chondrosarcoma correlate with poor prognosis. First, we analyzed the uPAR levels in tissues and plasma of five patients affected by chondrosarcoma. Interestingly, very high levels of uPAR and its soluble forms (SuPAR) were found on tumor cell surfaces and plasma, respectively, of two patients with lung metastases. Therefore, to investigate the role of SuPAR in chondrosaromas, we generated a primary cell culture from a chondrosarcoma tissue overexpressing uPAR on cell surfaces. We found that chondrosarcoma-like primary culture cells release a large amount of SuPAR in the medium. In vitro, SuPAR elicits chondrosarcoma cell migration likely through its uPAR88-92 sequence, since the DII88-183 or DIIDIIR88-284 uPAR domains retain motogen effect whereas DI1-87 or DIII184-284 domains, both lacking the uPAR88-92 sequence, are ineffective. Chondrosarcoma cells cross matrigel in response to SuPAR, and their invasion capability is abrogated by RERF peptide which inhibits uPAR88-92 signalling. These findings assign a role to uPAR in mobilizing chondrosarcoma cells and suggest that RERF peptide may be regarded as a prototype to generate new therapeutics for the chondrosarcoma treatment. PMID:21253510

  13. Effects of a 2-hour run on metabolic economy and lower extremity strength in men and women.

    PubMed

    Glace, B W; McHugh, M P; Gleim, G W

    1998-03-01

    Changes in running economy, or the oxygen cost of running at a given submaximal speed (ml/m/kg), during prolonged exercise have been well described in men but not in women. Lower extremity strength changes associated with prolonged exercise have never been addressed. We examined changes in running economy and strength following a 2-hour run in eight men and eight women. Knee and hip strength were measured pre- and post-running. Peak oxygen consumption (VO2peak) and oxygen consumption at ventilatory threshold were determined. Subjects then ran for 2 hours at an intensity which elicited ventilatory threshold (68.7% vs. 66.6% of VO2peak for men and women, p = 0.5). Water was ingested at a rate of 0.5% of body weight each half hour. Oxygen uptake (VO2) and respiratory exchange ratio were measured initially and at 1 and 2 hours. Body weight declined in the men (p = 0.001) but not in the women (p = 0.12). Running economy decreased in the men (p < 0.001) but not in the women (p = 0.084). At 2 hours of running, knee flexion and extension strength declined significantly in the men only (effect of gender x time, p < 0.014), but hip flexion, abduction, and adduction strength declined in both genders. Decreased knee extensor/flexor strength was evident in men only, while decreased hip strength was independent of gender. We conclude that 2 hours of running produced changes in knee strength and running economy in men only. PMID:9513864

  14. Efficacy of 2-hour post glucose insulin levels in predicting insulin resistance in polycystic ovarian syndrome with infertility

    PubMed Central

    Saxena, Pikee; Prakash, Anupam; Nigam, Aruna

    2011-01-01

    BACKGROUND: Insulin resistance (IR) is central to the pathogenesis of polycystic ovarian syndrome (PCOS), but tests for determining IR are elaborate, tedious and expensive. AIMS: To evaluate if “2-hour post-glucose insulin level” is an effective indicator of IR and can aid in diagnosing IR in infertile PCOS women. SETTINGS AND DESIGN: Observational study at infertility clinic of a tertiary care center. MATERIALS AND METHODS: 50 infertile women with PCOS and 20 females with tubal/male factor infertility were evaluated for the presence of IR, as defined by the fasting/2-hour post-glucose insulin levels cutoffs of >25/>41 μU/mL, respectively. The clinical, metabolic and endocrinologic profile was determined in both the groups. STATISTICAL ANALYSIS: Statistical analysis was performed using SPSS (Chicago, IL, USA). RESULTS: Body mass index, post load glucose, insulin, glucose/insulin ratio, area under curve (AUC) of glucose and insulin and insulinogenic index were significantly lower in the controls as compared to the PCOS group. “2-hour post-glucose insulin levels” were elevated in 88% of PCOS individuals but were normal in all females not suffering from PCOS. These levels significantly correlated with AUC of glucose and insulin, and insulinogenic index and inversely correlated with 2-hour glucose to insulin ratio (r=0.827, 0.749 and –0.732, respectively). CONCLUSIONS: “2-hour post-glucose insulin levels” appears to be a good indicator of IR. It can be a useful tool, especially in low resource setting where a single sample can confirm the diagnosis, thus reducing cost and repeat visits. PMID:21772735

  15. Urokinase plasminogen activator gene deficiency inhibits fracture cartilage remodeling.

    PubMed

    Popa, Nicoleta L; Wergedal, Jon E; Lau, K-H William; Mohan, Subburaman; Rundle, Charles H

    2014-03-01

    Urokinase plasminogen activator (uPA) regulates a proteolytic cascade of extracellular matrix degradation that functions in tissue development and tissue repair. The development and remodeling of the skeletal extracellular matrix during wound healing suggests that uPA might regulate bone development and repair. To determine whether uPA functions regulate bone development and repair, we examined the basal skeletal phenotype and endochondral bone fracture repair in uPA-deficient mice. The skeletal phenotype of uPA knockout mice was compared with that of control mice under basal conditions by dual-energy X-ray absorptiometry and micro-CT analysis, and during femur fracture repair by micro-CT and histological examination of the fracture callus. No effects of uPA gene deficiency were observed in the basal skeletal phenotype of the whole body or the femur. However, uPA gene deficiency resulted in increased fracture callus cartilage abundance during femur fracture repair at 14 days healing. The increase in cartilage corresponded to reduced tartrate-resistant acid phosphatase (TRAP) staining for osteoclasts in the uPA knockout fracture callus at this time, consistent with impaired osteoclast-mediated remodeling of the fracture cartilage. CD31 staining was reduced in the knockout fracture tissues at this time, suggesting that angiogenesis was also reduced. Osteoclasts also colocalized with CD31 expression in the endothelial cells of the fracture tissues during callus remodeling. These results indicate that uPA promotes remodeling of the fracture cartilage by osteoclasts that are associated with angiogenesis and suggest that uPA promotes angiogenesis and remodeling of the fracture cartilage at this time of bone fracture repair. PMID:23700285

  16. Regulation of epithelial sodium channels in urokinase plasminogen activator deficiency

    PubMed Central

    Chen, Zaixing; Zhao, Runzhen; Zhao, Meimi; Liang, Xinrong; Bhattarai, Deepa; Dhiman, Rohan; Shetty, Sreerama; Idell, Steven

    2014-01-01

    Epithelial sodium channels (ENaC) govern transepithelial salt and fluid homeostasis. ENaC contributes to polarization, apoptosis, epithelial-mesenchymal transformation, etc. Fibrinolytic proteases play a crucial role in virtually all of these processes and are elaborated by the airway epithelium. We hypothesized that urokinase-like plasminogen activator (uPA) regulates ENaC function in airway epithelial cells and tested that possibility in primary murine tracheal epithelial cells (MTE). Both basal and cAMP-activated Na+ flow through ENaC were significantly reduced in monolayers of uPA-deficient cells. The reduction in ENaC activity was further confirmed in basolateral membrane-permeabilized cells. A decrease in the Na+-K+-ATPase activity in the basolateral membrane could contribute to the attenuation of ENaC function in intact monolayer cells. Dysfunctional fluid resolution was seen in uPA-disrupted cells. Administration of uPA and plasmin partially restores ENaC activity and fluid reabsorption by MTEs. ERK1/2, but not Akt, phosphorylation was observed in the cells and lungs of uPA-deficient mice. On the other hand, cleavage of γ ENaC is significantly depressed in the lungs of uPA knockout mice vs. those of wild-type controls. Expression of caspase 8, however, did not differ between wild-type and uPA−/− mice. In addition, uPA deficiency did not alter transepithelial resistance. Taken together, the mechanisms for the regulation of ENaC by uPA in MTEs include augmentation of Na+-K+-ATPase, proteolysis, and restriction of ERK1/2 phosphorylation. We demonstrate for the first time that ENaC may serve as a downstream signaling target by which uPA controls the biophysical profiles of airway fluid and epithelial function. PMID:25172911

  17. Imaging Active Urokinase Plasminogen Activator in Prostate Cancer

    PubMed Central

    LeBeau, Aaron M.; Sevillano, Natalia; Markham, Kate; Winter, Michael B.; Murphy, Stephanie T.; Hostetter, Daniel R.; West, James; Lowman, Henry; Craik, Charles S.; VanBrocklin, Henry F.

    2015-01-01

    The increased proteolytic activity of membrane-bound and secreted proteases on the surface of cancer cells and in the transformed stroma is a common characteristic of aggressive metastatic prostate cancer. We describe here the development of an active site-specific probe for detecting a secreted peritumoral protease expressed by cancer cells and the surrounding tumor microenvironment. Using a human fragment antigen binding phage display library, we identified a human antibody termed U33 that selectively inhibited the active form of the protease urokinase plasminogen activator (uPA, PLAU). In the full-length immunoglobulin form, U33 IgG labeled with near-infrared fluorophores or radionuclides allowed us to non-invasively detect active uPA in prostate cancer xenograft models using optical and single-photon emission computed tomography (SPECT) imaging modalities. U33 IgG labeled with 111In had a remarkable tumor uptake of 43.2% injected dose per gram (%ID/g) 72hr post tail vein injection of the radiolabeled probe in subcutaneous xenografts. Additionally, U33 was able to image active uPA in small soft-tissue and osseous metastatic lesions using a cardiac dissemination prostate cancer model that recapitulated metastatic human cancer. The favorable imaging properties were the direct result of U33 IgG internalization through an uPA receptor mediated mechanism where U33 mimicked the function of the endogenous inhibitor of uPA to gain entry into the cancer cell. Overall, our imaging probe targets a prostate cancer-associated protease, through a unique mechanism, allowing for the non-invasive preclinical imaging of prostate cancer lesions. PMID:25672980

  18. Regime change?

    SciTech Connect

    Pilat, Joseph F.; Budlong-Sylvester, K. W.

    2004-01-01

    Following the 1998 nuclear tests in South Asia and later reinforced by revelations about North Korean and Iraqi nuclear activities, there has been growing concern about increasing proliferation dangers. At the same time, the prospects of radiological/nuclear terrorism are seen to be rising - since 9/11, concern over a proliferation/terrorism nexus has never been higher. In the face of this growing danger, there are urgent calls for stronger measures to strengthen the current international nuclear nonproliferation regime, including recommendations to place civilian processing of weapon-useable material under multinational control. As well, there are calls for entirely new tools, including military options. As proliferation and terrorism concerns grow, the regime is under pressure and there is a temptation to consider fundamental changes to the regime. In this context, this paper will address the following: Do we need to change the regime centered on the Treaty on the Nonproliferation of Nuclear Weapons (NPT) and the International Atomic Energy Agency (IAEA)? What improvements could ensure it will be the foundation for the proliferation resistance and physical protection needed if nuclear power grows? What will make it a viable centerpiece of future nonproliferation and counterterrorism approaches?

  19. Dietary Fatty Acids Differentially Associate with Fasting Versus 2-Hour Glucose Homeostasis: Implications for The Management of Subtypes of Prediabetes

    PubMed Central

    Guess, Nicola; Perreault, Leigh; Kerege, Anna; Strauss, Allison; Bergman, Bryan C.

    2016-01-01

    Over-nutrition has fuelled the global epidemic of type 2 diabetes, but the role of individual macronutrients to the diabetogenic process is not well delineated. We aimed to examine the impact of dietary fatty acid intake on fasting and 2-hour plasma glucose concentrations, as well as tissue-specific insulin action governing each. Normoglycemic controls (n = 15), athletes (n = 14), and obese (n = 23), as well as people with prediabetes (n = 10) and type 2 diabetes (n = 11), were queried about their habitual diet using a Food Frequency Questionnaire. All subjects were screened by an oral glucose tolerance test (OGTT) and studied using the hyperinsulinemic/euglycemic clamp with infusion of 6,62H2-glucose. Multiple regression was performed to examine relationships between dietary fat intake and 1) fasting plasma glucose, 2) % suppression of endogenous glucose production, 3) 2-hour post-OGTT plasma glucose, and 4) skeletal muscle insulin sensitivity (glucose rate of disappearance (Rd) and non-oxidative glucose disposal (NOGD)). The %kcal from saturated fat (SFA) was positively associated with fasting (β = 0.303, P = 0.018) and 2-hour plasma glucose (β = 0.415, P<0.001), and negatively related to % suppression of hepatic glucose production (β = -0.245, P = 0.049), clamp Rd (β = -0.256, P = 0.001) and NOGD (β = -0.257, P = 0.001). The %kcal from trans fat was also negatively related to clamp Rd (β = -0.209, P = 0.008) and NOGD (β = -0.210, P = 0.008). In contrast, the %kcal from polyunsaturated fat (PUFA) was negatively associated with 2-hour glucose levels (β = -0.383, P = 0.001), and positively related to Rd (β = 0.253, P = 0.007) and NOGD (β = 0.246, P = 0.008). Dietary advice to prevent diabetes should consider the underlying pathophysiology of the prediabetic state. PMID:26999667

  20. Effects of acute and 2-hour postphysical activity on the estimation of body fat made by the bod pod.

    PubMed

    Harrop, Bradley J; Woodruff, Sarah J

    2015-06-01

    The Bod Pod has been found to be reliable/valid against several criterion methods, including hydrostatic weighing and dual-energy x-ray absorptiometry, and under different conditions, such as clothing, dehydrated states, and body temperature changes. However, questions remain regarding the effects of an acute bout of exercise. Therefore, the purpose was to determine the effects of an acute bout of exercise on the estimations made by the Bod Pod. Participants (15 men and 22 women) were of age 18-27 years and were currently exercising. Baseline Bod Pod measures were completed followed by a 30-minute cycling trial at 75% of maximum heart rate. Bod Pod measures were taken immediately after exercise and 2 hours after exercise. Differences between men and women were found at baseline between height (p < 0.001), weight (p < 0.001), body volume (BV; p < 0.001), and body density (Db; p < 0.001). Among men, body mass (p < 0.001), body fat percentage (%BF; p < 0.001), and BV (p < 0.001) decreased, whereas Db (p < 0.001) and body temperature (p < 0.001) increased directly after exercise; body mass (p < 0.001) and BV (p < 0.001) remained lower after 2 hours. Among women, body mass (p < 0.001) and BV (p < 0.001) decreased, whereas thoracic gas volume (p = 0.014) and temperature (p < 0.001) increased directly after exercise; body mass (p < 0.001) and BV (p < 0.001) remained lower, whereas %BF (p < 0.001) and Db (p = 0.006) remained higher 2 hours after exercise. These results suggest that a single bout of exercise immediately before Bod Pod testing seems to alter the estimate of %BF, and continues to affect the prediction 2 hours after exercise in women. PMID:25756324

  1. Dietary Fatty Acids Differentially Associate with Fasting Versus 2-Hour Glucose Homeostasis: Implications for The Management of Subtypes of Prediabetes.

    PubMed

    Guess, Nicola; Perreault, Leigh; Kerege, Anna; Strauss, Allison; Bergman, Bryan C

    2016-01-01

    Over-nutrition has fuelled the global epidemic of type 2 diabetes, but the role of individual macronutrients to the diabetogenic process is not well delineated. We aimed to examine the impact of dietary fatty acid intake on fasting and 2-hour plasma glucose concentrations, as well as tissue-specific insulin action governing each. Normoglycemic controls (n = 15), athletes (n = 14), and obese (n = 23), as well as people with prediabetes (n = 10) and type 2 diabetes (n = 11), were queried about their habitual diet using a Food Frequency Questionnaire. All subjects were screened by an oral glucose tolerance test (OGTT) and studied using the hyperinsulinemic/euglycemic clamp with infusion of 6,62H2-glucose. Multiple regression was performed to examine relationships between dietary fat intake and 1) fasting plasma glucose, 2) % suppression of endogenous glucose production, 3) 2-hour post-OGTT plasma glucose, and 4) skeletal muscle insulin sensitivity (glucose rate of disappearance (Rd) and non-oxidative glucose disposal (NOGD)). The %kcal from saturated fat (SFA) was positively associated with fasting (β = 0.303, P = 0.018) and 2-hour plasma glucose (β = 0.415, P<0.001), and negatively related to % suppression of hepatic glucose production (β = -0.245, P = 0.049), clamp Rd (β = -0.256, P = 0.001) and NOGD (β = -0.257, P = 0.001). The %kcal from trans fat was also negatively related to clamp Rd (β = -0.209, P = 0.008) and NOGD (β = -0.210, P = 0.008). In contrast, the %kcal from polyunsaturated fat (PUFA) was negatively associated with 2-hour glucose levels (β = -0.383, P = 0.001), and positively related to Rd (β = 0.253, P = 0.007) and NOGD (β = 0.246, P = 0.008). Dietary advice to prevent diabetes should consider the underlying pathophysiology of the prediabetic state. PMID:26999667

  2. Urokinase-Treated Antithrombogenic Drains and Optimized Drain Placement in Endoscopic Lumbar Decompressive Surgery.

    PubMed

    Nakamura, Shu; Ikeda, Shoji; Taguchi, Mitsuto

    2016-07-01

    Background Spinal epidural hematoma (SEH) frequently occurs after microendoscopic decompressive laminotomy (MEDL), and a drain may not be functioning sufficiently. Objective To reduce the incidence of SEH after MEDL. Methods  A urokinase-treated antithrombogenic drain, which is available only with a large diameter, was reduced in diameter and used after MEDL. Magnetic resonance imaging (MRI) and computed tomography (CT) were performed 36 to 48 hours after surgery. The size of the SEH was measured by MRI, and the location of the drain tip was assessed by CT scan. After imaging, the drain was removed. Results Use of the urokinase-treated antithrombogenic drain reduced the incidence of SEH. However, the drain was not adequately placed in many cases, limiting the effect of the drainage. When the urokinase-treated antithrombogenic drain was placed contralaterally to the approach side using an unsheathed endoscope, the incidence of SEH was further reduced. Conclusions The urokinase-treated antithrombogenic drain prevented thrombus-related drain obstruction. In addition, unsheathed endoscopic contralateral placement of the drain was effective for SEH prevention. PMID:26935298

  3. Soluble urokinase plasminogen activation receptor - An emerging new biomarker of cardiovascular disease and critical illness

    PubMed Central

    Cyrille, Nicole B.; Villablanca, Pedro A.; Ramakrishna, Harish

    2016-01-01

    Soluble urokinase plasminogen activation receptor (suPAR) is an emerging new biomarker, which has been shown to not only correlate with traditional biomarkers but also outperform CRP at prognosticating CVD. More clinical trials on suPAR is in the future research agenda. PMID:27052059

  4. Delta CK-MB outperforms delta troponin I at 2 hours during the ED rule out of acute myocardial infarction.

    PubMed

    Fesmire, F M

    2000-01-01

    It has been shown that a rise in creatine kinase MB bank (CK-MB) of > or = + 1.6 ng/mL in 2 hours is more sensitive and equally specific for detection of acute myocardial infarction (AMI) as compared with a 2-hour CK-MB > or = 6 ng/mL during the emergency department (ED) evaluation of chest pain. Because cardiac specific troponin I (cTnI) is thought to have similar early release kinetics as compared with CK-MB mass, we undertook a retrospective cohort study in 578 chest pain patients whose baseline CK-MB and cTnI was less than two times the hospital's upper limits of normal and who underwent a 2-hour CK-MB and cTnI to compare sensitivities and specificities of the 2-hour delta CK-MB (deltaCK-MB) and delta cTnI (delta cTnI) for AMI and 30-day Adverse Outcome (AO). Thirty day AO was defined as AMI, life-threatening complication, death, or percutaneous transluminal coronary angioplasty (PTCA)/coronary artery bypass graft (CABG) within 30 days of ED presentation. Optimum delta values were determined by choosing the smallest cutoff value greater than the assay precision where the deltaCK-MB and delta cTnI had a positive likelihood ratio for 30-day AO of > or = 15. A deltaCK-MB > or = +1.5 ng/mL was more sensitive than a deltaTnI > or = +0.2 ng/mL for AMI (87.7% versus 61.4%; P < .0005) and 30-day AO (56.7% versus 42.3%; P < .005). There were no differences in specificities for AMI and 30-day AO. Combining the two tests (MBdelta > or = +1.5 ng/mL and/or a deltaTnI > or = +0.2 ng/mL) resulted in an incremental increase in sensitivity of 89.5% for AMI and 61.9% for AO (P < .005). Patients with either a rise in CK-MB of > or = +1.5 ng/mL or rise in cTnI of > or = +0.2 ng/mL in 2 hours should receive consideration for aggressive antiischemic therapy and further diagnostic testing before making an exclusionary diagnosis of nonischemic chest pain. PMID:10674522

  5. Virtual Screening Targeting the Urokinase Receptor, Biochemical and Cell-Based Studies, Synthesis, Pharmacokinetic Characterization, and Effect on Breast Tumor Metastasis

    PubMed Central

    Wang, Fang; Li, Jing; Sinn, Anthony L.; Knabe, William Eric; Khanna, May; Jo, Inha; Silver, Jayne M.; Oh, Kyungsoo; Li, Liwei; Sandusky, George E.; Sledge, George W.; Nakshatri, Harikrishna; Jones, David R.; Pollok, Karen E.; Meroueh, Samy O.

    2011-01-01

    Virtual screening targeting the urokinase receptor (uPAR) led to (3R)-4-cyclohexyl-3-(hexahydrobenzo[d][1,3]dioxol-5-yl)-N-((hexahydrobenzo[d][1,3]dioxol-5-yl)methyl)butan-1-aminium 1 (IPR-1) and 4-(4-((3,5-dimethylcyclohexyl)carbamoyl)-2-(4-isopropylcyclohexyl)pyrazolidin-3-yl)piperidin-1-ium 3 (IPR-69). Synthesis of an analog of 1, namely 2 (IPR-9), and 3 led to breast MDA-MB-231 invasion, migration and adhesion assays with IC50 near 30 μM. Both compounds blocked angiogenesis with IC50 of 3 μM. Compounds 2 and 3 inhibited cell growth with IC50 of 6 and 18 μM and induced apoptosis. Biochemical assays revealed lead-like properties for 3, but not 2. Compound 3 administered orally reached peak concentration of nearly 40 μM with a half-life of about 2 hours. In NOD-SCID mice inoculated with breast TMD-231 cells in their mammary fat pads, compound 3 showed a 20% reduction in tumor volumes and less extensive metastasis was observed for the treated mice. The suitable pharmacokinetic properties of 3 and the encouraging preliminary results in metastasis make it an ideal starting point for next generation compounds. PMID:21851064

  6. Induction of Brain Microvascular Endothelial Cell Urokinase Expression by Cryptococcus neoformans Facilitates Blood-Brain Barrier Invasion

    PubMed Central

    Stie, Jamal; Fox, Deborah

    2012-01-01

    The invasive ability of the blood-borne fungal pathogen Cryptococcus neoformans can be enhanced through interactions with host plasma components, such as plasminogen. Previously we showed by in vitro studies that plasminogen coats the surface of C. neoformans and is converted to the active serine protease, plasmin, by host plasminogen activators. Viable, but not formaldehyde- or sodium azide-killed, cryptococcal strains undergo brain microvascular endothelial cell-dependent plasminogen-to-plasmin activation, which results in enhanced, plasmin-dependent cryptococcal invasion of primary bovine brain microvascular endothelial cells and fungal ability to degrade plasmin substrates. In the present work, brain microvascular endothelial cells cultured with viable, but not killed, cryptococcal strains led to significant increases in both urokinase mRNA transcription and cell-associated urokinase protein expression. Soluble urokinase was also detected in conditioned medium from brain microvascular endothelial cells cultured with viable, but not killed, C. neoformans. Exposure of plasminogen pre-coated viable C. neoformans to conditioned medium from strain-matched brain microvascular endothelial cell-fungal co-cultures resulted in plasminogen-to-plasmin activation and plasmin-dependent cryptococcal invasion. siRNA-mediated silencing of urokinase gene expression or the use of specific inhibitors of urokinase activity abrogated both plasminogen-to-plasmin activation on C. neoformans and cryptococcal-brain microvascular endothelial cell invasion. Our results suggest that pathogen exploitation of the host urokinase-plasmin(ogen) system may contribute to C. neoformans virulence during invasive cryptococcosis. PMID:23145170

  7. Effect of urokinase on the proliferation of primary cultures of human prostatic cells

    SciTech Connect

    Kirchheimer, J.C.; Wojta, J.; Hienert, G.; Christ, G.; Heger, M.E.; Pflueger, H.B.; Binder, B.R.

    1987-11-01

    The effects of exogenously added urokinase type plasminogen activator, tissue type plasminogen activator, plasmin and thrombin on the proliferation of primary cultures of cells derived from prostatic hyperplasia or prostatic carcinomas were investigated by measuring the incorporation of /sup 3/H-thymidine into the cultures. Addition of urokinase type plasminogen activator (1.35 x 10(-9) M) or thrombin (10(-7) M) to the culture medium caused a two-fold increase of /sup 3/H-thymidine incorporation, regardless of the origin of the prostatic cells. Tissue type plasminogen activator did not alter the rate of /sup 3/H-thymidine incorporation, whereas plasmin caused a 25% decrease of /sup 3/H-thymidine incorporation in all cultures.

  8. Targeting the urokinase plasminogen activator receptor enhances gene transfer to human airway epithelia

    PubMed Central

    Drapkin, Paola T.; O’Riordan, Catherine R.; Yi, Su Min; Chiorini, John A.; Cardella, Jonathan; Zabner, Joseph; Welsh, Michael J.

    2000-01-01

    Developing gene therapy for cystic fibrosis has been hindered by limited binding and endocytosis of vectors by human airway epithelia. Here we show that the apical membrane of airway epithelia express the urokinase plasminogen activator receptor (uPAR). Urokinase plasminogen activator (uPA), or a 7-residue peptide derived from this protein (u7-peptide), bound the receptor and stimulated apical endocytosis. Both ligands enhanced gene transfer by nonspecifically bound adenovirus and adeno-associated virus vectors and by a modified adenovirus vector that had been coupled to the u7-peptide. These data provide the first evidence that targeting an apical receptor can circumvent the two most important barriers to gene transfer in airway epithelia. Thus, the uPA/uPAR system may offer significant advantages for delivering genes and other pharmaceuticals to airway epithelia. PMID:10712430

  9. Targeting the urokinase plasminogen activator receptor enhances gene transfer to human airway epithelia.

    PubMed

    Drapkin, P T; O'Riordan, C R; Yi, S M; Chiorini, J A; Cardella, J; Zabner, J; Welsh, M J

    2000-03-01

    Developing gene therapy for cystic fibrosis has been hindered by limited binding and endocytosis of vectors by human airway epithelia. Here we show that the apical membrane of airway epithelia express the urokinase plasminogen activator receptor (uPAR). Urokinase plasminogen activator (uPA), or a 7-residue peptide derived from this protein (u7-peptide), bound the receptor and stimulated apical endocytosis. Both ligands enhanced gene transfer by nonspecifically bound adenovirus and adeno-associated virus vectors and by a modified adenovirus vector that had been coupled to the u7-peptide. These data provide the first evidence that targeting an apical receptor can circumvent the two most important barriers to gene transfer in airway epithelia. Thus, the uPA/uPAR system may offer significant advantages for delivering genes and other pharmaceuticals to airway epithelia. PMID:10712430

  10. Proteolytic regulation of epithelial sodium channels by urokinase plasminogen activator: cutting edge and cleavage sites.

    PubMed

    Ji, Hong-Long; Zhao, Runzhen; Komissarov, Andrey A; Chang, Yongchang; Liu, Yongfeng; Matthay, Michael A

    2015-02-27

    Plasminogen activator inhibitor 1 (PAI-1) level is extremely elevated in the edematous fluid of acutely injured lungs and pleurae. Elevated PAI-1 specifically inactivates pulmonary urokinase-type (uPA) and tissue-type plasminogen activators (tPA). We hypothesized that plasminogen activation and fibrinolysis may alter epithelial sodium channel (ENaC) activity, a key player in clearing edematous fluid. Two-chain urokinase (tcuPA) has been found to strongly stimulate heterologous human αβγ ENaC activity in a dose- and time-dependent manner. This activity of tcuPA was completely ablated by PAI-1. Furthermore, a mutation (S195A) of the active site of the enzyme also prevented ENaC activation. By comparison, three truncation mutants of the amino-terminal fragment of tcuPA still activated ENaC. uPA enzymatic activity was positively correlated with ENaC current amplitude prior to reaching the maximal level. In sharp contrast to uPA, neither single-chain tPA nor derivatives, including two-chain tPA and tenecteplase, affected ENaC activity. Furthermore, γ but not α subunit of ENaC was proteolytically cleaved at ((177)GR↓KR(180)) by tcuPA. In summary, the underlying mechanisms of urokinase-mediated activation of ENaC include release of self-inhibition, proteolysis of γ ENaC, incremental increase in opening rate, and activation of closed (electrically "silent") channels. This study for the first time demonstrates multifaceted mechanisms for uPA-mediated up-regulation of ENaC, which form the cellular and molecular rationale for the beneficial effects of urokinase in mitigating mortal pulmonary edema and pleural effusions. PMID:25555911

  11. [Significance of urokinase and its inhibitors in the invasiveness and metastasing of malignant tumors].

    PubMed

    Halámková, J; Kiss, I; Tomášek, J; Pavlovský, Z; Tuček, S; Penka, M

    2012-02-01

    Fibrinolysis is process, which leads to the degradation of fibrin to fibrin monomers. Fibrinolysis helps to regulate hemostasis and prevents the creation of inappropriately large thrombus, which could reduce blood flow to the bloodstream. The main enzyme involved in fibrinolysis is plasmin. Tissue plasminogen activator (tPA) and urokinase (uPA) are agents converting plasminogen into active plasmin, together with urokinase receptor (uPAR) and urokinase inhibitors (PAI 1, PAI 2, PAI 3 and protease nexin) form plasminogen activator system (PAS) which is among others also part of the metastatic cascade and significantly contributes to invasive growth and angiogenesis of malignant tumours. In contrast to tPA that is fundamental in fibrinolysis, uPA plays an essential role in tissue degradation as part of physiological and pathological processes. uPAR is a GPI (glycosylphosphatidylinositol)-anchored protein. The binding of uPA to uPAR results in activation of protein tyrosine kinase, protein kinase C and MAP kinase. At the same time, direct signalling pathway via Jak/STAT cascade utilising signalling transduction of Scr-like protein tyrosine kinase have also been described. uPAR expression is regulated by many growth factors, e.g. EGF, FGF-2 and HGF. It seems that individual PAS factors are involved in the process of rendering malignant tumors invasive. To what degree this influence is essential to specific malignancies, should be answered by further research. In the article the authors present a summary of findings about the interaction of fibrinolysis and tumor process, especially on the effects of urokinase and other activators and their inhibitors in metastasis of malignant tumors. The text contains information on the factors theirs introduction into practice is still the subject of numerous discussions, but in the future, individual PAS factors could play an important role in planning treatment strategies and also could become targets of targeted therapy. PMID

  12. Flushing the liver with urokinase before transplantation does not prevent nonanastomotic biliary strictures.

    PubMed

    Pietersen, Lars C; den Dulk, A Claire; Braat, Andries E; Putter, Hein; Korkmaz, Kerem Sebib; Baranski, Andre G; Schaapherder, Alexander F M; Dubbeld, Jeroen; van Hoek, Bart; Ringers, Jan

    2016-04-01

    The aim of the present study was to assess whether flushing the donor liver with urokinase immediately before implantation reduces the incidence of nonanastomotic biliary strictures (NASs) after liver transplantation, without causing increased blood loss, analyzed as a historical cohort study. Between January 2005 and October 2012, all liver (re-)transplantations were included. Of the 185 liver transplant recipients included, 63 donor livers between January 2010 and October 2012 received urokinase (study group), whereas the donor liver of 122 consecutive recipients, who served as a historical control group, between January 2005 and January 2010 did not receive urokinase. Basic donor (Eurotransplant donor risk index) and recipient (age, body mass index, laboratory Model for End-Stage Liver Disease score) characteristics did not significantly differ in both groups. Thirty-three recipients developed NASs: 22 in the control group (18%) and 11 (17.5%) in the study group (P = 0.68). Analyzed separately for donation after circulatory death (P = 0.42) or donation after brain death (P = 0.89), there was no difference between the groups in incidence of NAS. Of all the recipients developing NAS, 7 (21%) needed retransplantation and all others were treated conservatively. Autologous blood transfusion requirements did not differ significantly between both groups (P = 0.91), whereas interestingly, more heterologous blood transfusions were needed in the control group (P < 0.001). This study has its limitations by its retrospective character. A multi-institutional prospective study could clarify this issue. In conclusion, arterial flushing of the liver with urokinase immediately before implantation did not lead to a lower incidence of NAS in this study, nor did it lead to increased blood loss. Liver Transplantation 22 420-426 2016 AASLD. PMID:26600096

  13. Design of a 2-Hour Prebreathe Protocol for Space Walks (EVAs) from the International Space Station (ISS)

    NASA Technical Reports Server (NTRS)

    Gernhardt, M. L.; Conkin, J.; Foster, P. P.; Pilmanis, A. A.; Butler, B. D.; Fife, C.; Vann, R. D.; Gerth, W. A.; Loftin, K. C.; Dervay, J.; Waligora, J. M.; Powell, M. R.; Homick, Jerry L. (Technical Monitor)

    2000-01-01

    The majority of extravehicular activities (EVAs) performed from the shuttle use a 10.2 psi staged decompression. The International Space Station (ISS) will operate at 14.7 psi, requiring crews to "campout" in the airlock at 10.2 psi. The constraints associated with campout (crew isolation, oxygen usage, and waste management), provided the rationale to develop a 2-hour prebreathe protocol from 14.7 psi. Previous studies on the affect of microgravity and exercise during prebreathe suggested the feasibility of this approach. Various combinations of adynamia (nonwalking subjects), prebreathe exercise doses, and space suit donning options (10.2 vs. 14.7 psi) were analyzed against timeline and consumable constraints. Prospective decompression sickness (DCS) and venous gas emboli (VGE) accept/reject criteria were defined from statistical analysis of historical DCS data, combined with risk management of DCS under ISS mission circumstances. Maximum operational DCS levels were defined based on protecting for EVA capability with two crew members at 95% confidence, throughout ISS lifetime (within the constraints of NASA DCS disposition policy JPG 1800.3). The accept / reject limits were adjusted for greater safety (including Grade IV VGE criteria) based on analysis of related medical factors. Monte-Carlo simulation was performed to design a closed sequential, multi-center laboratory trial, including the capability of rejecting the primary protocol and testing at least one alternate exercise dose, within the 2-hour prebreathe. The 2-hour protocol incorporates 0, breathing for 5 0 min at 14.7 psi, including 10 min dual cycle ergometry at 75%VO(2max). It requires an additional 30 minO2breathing during depress from 14.7 to 10.2 psi, followed by a 30-60 min suit donning break at 10.2 psi/26.5% O2. It concludes with a 40 min in-suit O2 prebreathe. The protocol would be accepted for operations, if the incidence of DCS was less than 15% and Grade IV VGE less than 20%, both at 95

  14. Urokinase perfusion prevents intrahepatic ischemic-type biliary lesion in donor livers

    PubMed Central

    Lang, Ren; He, Qiang; Jin, Zhong-Kui; Han, Dong-Dong; Chen, Da-Zhi

    2009-01-01

    AIM: To evaluate whether urokinase perfusion of non-heart-beating cadaveric donor livers reduces the incidence of intrahepatic ischemic-type biliary lesions (IITBLs). METHODS: A prospective study was conducted to investigate potential microthrombosis in biliary microcirculation when non-heart-beating cadaveric livers were under warm or cold ischemic conditions. The experimental group included 140 patients who underwent liver transplantation during the period of January 2006 to December 2007, and survived for more than 1 year. The control group included 220 patients who received liver transplantation between July 1999 and December 2005 and survived for more than 1 year. In the experimental group, the arterial system of the donor liver was perfused twice with urokinase during cold perfusion and after trimming of the donor liver. The incidence of IITBLs was compared between the two groups. RESULTS: In the control group, the incidence of IITBLs was 5.9% (13/220 cases) after 3-11 mo of transplantation. In the experimental group, two recipients (1.4%) developed IITBLs at 3 and 6 mo after transplantation, respectively. The difference in the incidence between the two groups was statistically significant (P < 0.05). CONCLUSION: Double perfusion of cadaveric livers from non-heart-beating donors with urokinase may reduce the incidence of IITBLs. PMID:19630111

  15. Structural Basis of Interaction Between Urokinase-type Plasminogen Activator and its Receptor

    SciTech Connect

    Barinka,C.; Parry, G.; Callahan, J.; Shaw, D.; Kuo, A.; Cines, B.; Mazar, A.; Lubkowski, J.

    2006-01-01

    Recent studies indicate that binding of the urokinase-type plasminogen activator (uPA) to its high-affinity receptor (uPAR) orchestrates uPAR interactions with other cellular components that play a pivotal role in diverse (patho-)physiological processes, including wound healing, angiogenesis, inflammation, and cancer metastasis. However, notwithstanding the wealth of biochemical data available describing the activities of uPAR, little is known about the exact mode of uPAR/uPA interactions or the presumed conformational changes that accompany uPA/uPAR engagement. Here, we report the crystal structure of soluble urokinase plasminogen activator receptor (suPAR), which contains the three domains of the wild-type receptor but lacks the cell-surface anchoring sequence, in complex with the amino-terminal fragment of urokinase-type plasminogen activator (ATF), at the resolution of 2.8 {angstrom}. We report the 1.9 {angstrom} crystal structure of free ATF. Our results provide a structural basis, represented by conformational changes induced in uPAR, for several published biochemical observations describing the nature of uPAR/uPA interactions and provide insight into mechanisms that may be responsible for the cellular responses induced by uPA binding.

  16. Design and Testing of a 2-Hour Oxygen Prebreathe Protocol for Space Walks from the International Space Station

    NASA Technical Reports Server (NTRS)

    Gernhardt, Michael L.; Conkin, J.; Foster, P. P.; Pilmanis, A. A.; Butler, B. D.; Beltran, E.; Fife, C. E.; Vann, R. D.; Gerth, W. A.; Loftin, K. C.; Paloski, William H. (Technical Monitor)

    2000-01-01

    To develop and test a 2-hour prebreathe protocol for performing extravehicular activities (EVAs) from the International Space Station (ISS). Combinations of adynamia (non-walking), prebreathe exercise, and space suit donning options (10.2 vs. 14.7 psi) were evaluated, against timeline and consumable contraints to develop an operational 2- hour prebreathe protocol. Prospective accept/reject criteria were defined for decompression sickness (DCS) and venous gas emboli (VGE) from analysis of historical DCS data, combined with risk management of DCS under ISS mission circumstances. Maximum operational DCS levels were defined based on protecting for EVA capability with two crew-members at 95% confidence, throughout ISS lifetime (within the constraints of NASA DCS disposition policy JPG 1800.3). The accept/reject limits were adjusted for greater safety based on analysis of related medical factors. Monte-Carlo simulation was performed to design a closed sequential, multi-center human trial. Protocols were tested with 4 different prebreathe exercises (Phases I-IV), prior to exposure to 4.3 psi for 4 hrs. Subject selection, Doppler monitoring for VGE, test termination criteria, and DCS definitions were standardized. Phase I: upper and lower body exercises using dual-cycle ergometry (75% VO2 max for 10 min). Phase II: ergometry plus 24 min of light exercise (simulating space-suit preparations). Phase III: same 24 min of light exercise but no ergometry, and Phase IV: 56 min of light exercise without ergometry. A prebreathe procedure was accepted if, at 95% confidence, the incidence of DCS was less than 15% (with no Type II DCS), and Grade IV VGE was less than 20%.

  17. Tirofiban combined with urokinase selective intra-arterial thrombolysis for the treatment of middle cerebral artery occlusion

    PubMed Central

    FENG, LEI; LIU, JUN; LIU, YUNZHEN; CHEN, JIAN; SU, CHUNHAI; LV, CHUANFENG; WEI, YUZHEN

    2016-01-01

    The aims of the present study were to establish a model of embolic stroke in rabbits and to evaluate the efficacy and safety of intra-arterially administered tirofiban combined with urokinase thrombolysis. The middle cerebral artery occlusion model (MCAO) of embolic stroke was established in New Zealand rabbits via an autologous clot. The model rabbits were allocated at random into four groups: Tirofiban group (T group), urokinase group (UK group), tirofiban and urokinase group (T + UK group) and the control group (C group). The recanalization rate, relative-apparent diffusion coefficient (rADC) and neurological function deficit score (NFDS) values were compared among the four groups. The recanalization rate, rADC and NFDS values were improved in the T + UK group compared with the other groups. In summary, the intra-arterial administration of tirofiban combined with urokinase thrombolysis was a more effective intervention in an MCAO model compared with intra-arterial urokinase alone, and may promote reperfusion and reduce infarct volume. PMID:26998029

  18. Reproducibility of the pulmonary function response of older men and women to a 2-hour ozone exposure

    SciTech Connect

    Bedi, J.F.; Horvath, S.M.; Drechsler-Parks, D.M.

    1988-08-01

    To test the reproducibility of the pulmonary function response to ozone exposure in older individuals, eight men and eight women, average age 62.8 years, participated in three 2-hour exposures to 0.45 ppm ozone at 23.3 C and 62.5 percent relative humidity. The first and second exposures were separated by an average time of 17.2 days, and 27.3 days separated the second and third exposures. Subjects alternated riding a bicycle ergometer for 20 minutes at an average minute ventilation of 26 liters BTPS (body temperature pressure, saturated), with 20-minute rest periods. Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV-1), and forced expiratory flow between 25 and 75% of FVC (FEF 25-75%) were measured pre and post exposure. The reproducibility of individual pre-post changes were assessed by calculation of the best linear fit and correlation coefficients between exposures. For FVC and FEV-1, the slopes were significantly different from 1, and correlation coefficients not significantly different from zero, implying that older individuals may not respond consistently to similar ozone exposures.

  19. Effects of bacteria involved with the pathogenesis of infection-induced urolithiasis on the urokinase and sialidase (neuraminidase) activity.

    PubMed

    du Toit, P J; van Aswegen, C H; Steyn, P L; Pols, A; du Plessis, D J

    1992-01-01

    It has been hypothesized that urinary urokinase and sialidase may play a role in urolithiasis. If these theories have substance it is to be expected that microorganisms may also affect these enzymes, since the association between urinary tract infection and renal stone formation is well known. It is generally assumed that Proteus mirabilis and Staphylococcus albus, which produce the urea-splitting enzyme urease, are responsible for stone formation. However, the importance of non-urease-producing microorganisms (Escherichia coli and Enterococcus) in urolithiasis is unclear. Spectrophotometric studies were therefore devised to clarify this problem. Microorganisms associated with infection-induced stones (Proteus mirabilis and Escherichia coli) respectively inhibited the urokinase and stimulated the sialidase activity. In contrast, microorganisms which were not associated with infection stones (Bacillus subtilis) had significantly less effect on urokinase and sialidase activity. This study may explain infection-induced stone formation and could open a completely new line of research. PMID:1462476

  20. Role of urokinase and its receptor in basal and stimulated colonic epithelial cell migration in vitro

    PubMed Central

    Wilson, A; Gibson, P

    2000-01-01

    BACKGROUND—Migration of colonic epithelial cells is important for mucosal repair following injury. The urokinase (u-PA) system regulates migration in other cell types.
AIM—To examine the role of u-PA and its receptor (u-PAR) in colonic epithelial cell migration.
METHODS—Migration was assessed over 24 hours in circular wounds made in confluent monolayers of LIM1215 and Caco-2 human colon cancer cells. The function of u-PA and u-PAR was ablated with antisense oligonucleotides to block expression, with synthetic u-PA peptides to block interaction, and with aprotinin to block u-PA mediated proteolysis.
RESULTS—Migration was stimulated two to threefold by exogenous u-PA, an effect dependent on u-PAR binding but independent of u-PA mediated mitogenesis and proteolysis. Expression of u-PA and u-PAR was inhibited by 80% by the appropriate antisense oligonucleotide. Basal migration and the motogenic effects of butyrate, epidermal growth factor, and phorbol-12-myristate-13-acetate were suppressed by the u-PAR antisense oligonucleotide (40-60%) but were at best minimally affected following inhibition of u-PA expression and binding. 
CONCLUSIONS—In an in vitro model of wounded colonic epithelium, u-PAR promotes cell migration through mechanisms that are not exclusively dependent on u-PA binding. Therefore, u-PA and u-PAR may contribute to colonic mucosal repair in vivo.


Keywords: colon; migration; urokinase; urokinase receptor; epidermal growth factor; butyrate; protein kinase C PMID:10861271

  1. Performance of the 2-hour Accelerated Diagnostic Protocol Within the American College of Radiology Imaging Network PA 4005 Cohort

    PubMed Central

    Mahler, Simon A.; Miller, Chadwick D.; Litt, Harold I.; Gatsonis, Constantine A.; Snyder, Bradley S.; Hollander, Judd E.

    2015-01-01

    Objectives The 2-hour accelerated diagnostic protocol (ADAPT) is a decision rule designed to identify emergency department (ED) patients with chest pain for early discharge. Previous studies in the Asia-Pacific region demonstrated high sensitivity (97.9% to 99.7%) for major adverse cardiac events (MACE) at 30 days. The objective of this study was to determine the validity of ADAPT for risk stratification in a cohort of U.S. ED patients with suspected acute coronary syndrome (ACS). Methods A secondary analysis of participants enrolled in the American College of Radiology Imaging Network (ACRIN) PA 4005 trial was conducted. This trial enrolled 1,369 patients at least 30 years old with symptoms suggestive of ACS. All data elements were collected prospectively at the time of enrollment. Each patient was classified as low risk or at risk by ADAPT. Early discharge rate and sensitivity for MACE, defined as cardiac death, myocardial infarction (MI), or coronary revascularization at 30 days, were calculated. Results Of 1,140 patients with complete biomarker data, MACE occurred in 31 patients (2.7%). Among 551 of the 1,140 (48.3%, 95% confidence interval [CI] = 45.4% to 51.3%), ADAPT identified for early discharge; five of the 551 (0.9%, 95% CI = 0.3% to 2.1%) had MACE at 30 days. ADAPT was 83.9% (95% CI = 66.3% to 94.5%) sensitive, identifying 26 of 31 patients with MACE. Of the five patients identified for early discharge by ADAPT with MACE, there were no deaths, one patient with MI, and five with revascularizations. Conclusions In this first North American application of the ADAPT strategy, sensitivity for MACE within 30 days was 83.9%. One missed adverse event was a MI, with the remainder representing coronary revascularizations. The effect of missing revascularization events needs further investigation. PMID:25810343

  2. Urokinase infusion of chronically occluded femoropopliteal Gortex bypass grafts via the popliteal approach.

    PubMed

    Dorros, G; Hall, P; Iyer, S S

    1991-11-01

    Thrombolysis of two occluded above-knee femoropopliteal Gortex bypass grafts utilizing the popliteal approach for catheter placement was successfully performed without complication. In both cases, the proximal anastomoses of the graft could not be identified. A percutaneous popliteal approach was used for catheter placement and delivery of urokinase. Angioplasty was performed on the unveiled stenoses that, presumptively, led to graft closure. Selective thrombolysis via catheter placed from popliteal approach is a new technique for recanalization of occluded femoropopliteal bypass grafts and warrants further investigation. PMID:1764742

  3. Comparison of the Current Diagnostic Criterion of HbA1c with Fasting and 2-Hour Plasma Glucose Concentration.

    PubMed

    Karnchanasorn, Rudruidee; Huang, Jean; Ou, Horng-Yih; Feng, Wei; Chuang, Lee-Ming; Chiu, Ken C; Samoa, Raynald

    2016-01-01

    To determine the effectiveness of hemoglobin A1c (HbA1c) ≥ 6.5% in diagnosing diabetes compared to fasting plasma glucose (FPG) ≥ 126 mg/dL and 2-hour plasma glucose (2hPG) ≥ 200 mg/dL in a previously undiagnosed diabetic cohort, we included 5,764 adult subjects without established diabetes for whom HbA1c, FPG, 2hPG, and BMI measurements were collected. Compared to the FPG criterion, the sensitivity of HbA1c ≥ 6.5% was only 43.3% (106 subjects). Compared to the 2hPG criterion, the sensitivity of HbA1c ≥ 6.5% was only 28.1% (110 subjects). Patients who were diabetic using 2hPG criterion but had HbA1c < 6.5% were more likely to be older (64 ± 15 versus 60 ± 15 years old, P = 0.01, mean ± STD), female (53.2% versus 38.2%, P = 0.008), leaner (29.7 ± 6.1 versus 33.0 ± 6.6 kg/m(2), P = 0.000005), and less likely to be current smokers (18.1% versus 29.1%, P = 0.02) as compared to those with HbA1c ≥ 6.5%. The diagnostic agreement in the clinical setting revealed the current HbA1c ≥ 6.5% is less likely to detect diabetes than those defined by FPG and 2hPG. HbA1c ≥ 6.5% detects less than 50% of diabetic patients defined by FPG and less than 30% of diabetic patients defined by 2hPG. When the diagnosis of diabetes is in doubt by HbA1c, FPG and/or 2hPG should be obtained. PMID:27597979

  4. Comparison of the Current Diagnostic Criterion of HbA1c with Fasting and 2-Hour Plasma Glucose Concentration

    PubMed Central

    Karnchanasorn, Rudruidee; Huang, Jean; Feng, Wei; Chuang, Lee-Ming

    2016-01-01

    To determine the effectiveness of hemoglobin A1c (HbA1c) ≥ 6.5% in diagnosing diabetes compared to fasting plasma glucose (FPG) ≥ 126 mg/dL and 2-hour plasma glucose (2hPG) ≥ 200 mg/dL in a previously undiagnosed diabetic cohort, we included 5,764 adult subjects without established diabetes for whom HbA1c, FPG, 2hPG, and BMI measurements were collected. Compared to the FPG criterion, the sensitivity of HbA1c ≥ 6.5% was only 43.3% (106 subjects). Compared to the 2hPG criterion, the sensitivity of HbA1c ≥ 6.5% was only 28.1% (110 subjects). Patients who were diabetic using 2hPG criterion but had HbA1c < 6.5% were more likely to be older (64 ± 15 versus 60 ± 15 years old, P = 0.01, mean ± STD), female (53.2% versus 38.2%, P = 0.008), leaner (29.7 ± 6.1 versus 33.0 ± 6.6 kg/m2, P = 0.000005), and less likely to be current smokers (18.1% versus 29.1%, P = 0.02) as compared to those with HbA1c ≥ 6.5%. The diagnostic agreement in the clinical setting revealed the current HbA1c ≥ 6.5% is less likely to detect diabetes than those defined by FPG and 2hPG. HbA1c ≥ 6.5% detects less than 50% of diabetic patients defined by FPG and less than 30% of diabetic patients defined by 2hPG. When the diagnosis of diabetes is in doubt by HbA1c, FPG and/or 2hPG should be obtained. PMID:27597979

  5. The Heparin-Induced Thrombocytopenia and Thrombosis Syndrome: Treatment with Intraarterial Urokinase and Systemic Platelet Aggregation Inhibitors

    SciTech Connect

    Murphy, Kenneth D.; McCrohan, Gerard; DeMarta, Deborah A.; Shirodkar, Nitin B.; Kwon, Oun J.; Chopra, Paramjit S.

    1996-03-15

    We report a case of the heparin-induced thrombocytopenia and thrombosis syndrome presenting with acute ischemia of a lower limb. The patient was successfully treated by withdrawal of heparin products, intraarterial urokinase, and platelet anti-aggregation therapy consisting of Dextran and aspirin.

  6. Bound plasminogen is rate-limiting for cell-surface-mediated activation of plasminogen by urokinase.

    PubMed Central

    Namiranian, S; Naito, Y; Kakkar, V V; Scully, M F

    1995-01-01

    The ability of U937 monocyte-like cells and KATO III cells (a human gastric carcinoma line) to potentiate activation of plasminogen by single-chain urokinase-type plasminogen activator (scu-PA), as mediated by the cell receptor for urokinase (u-PAR), was compared. It was observed that, although the concentration of u-PAR on these cell lines differed considerably (U937 cells: 5000 receptors/cell, Kd 0.35 nM; KATO III cells: 400 receptors/cell, Kd 0.85 nM), the rate of activation of plasminogen by scu-PA in the presence of the same density of each cell line was equivalent. From data generated in the presence of increasing concentrations of scu-PA, the kcat, for plasminogen activation in the presence of each cell line was calculated and found to differ by 26-fold (0.36 s-1 on U937 cells; 9.25 s-1 on KATO III cells). However, the Km for plasminogen with respect to the rate of formation of plasmin was lower than the Kd for binding (0.2 microM compared with 0.5 microM on U937 cells; 0.34 microM compared with 1.6 microM on KATO III cells). A rapid transformation from Glu-plasminogen (native plasminogen with N-terminal Glu) to Lys-plasminogen (plasmin-degraded plasminogen with primarily N-terminal Lys-77) occurred on the surface of U937 cells (unlike KATO III cells), but this transition did not coincide with faster rates of plasminogen activation. From this evidence it is concluded that the accessibility of bound plasminogen acts to limit the rate of activation by cell-bound urokinase. The significance of this proposal is that the proteolytic potential of the cell-mediated activation of plasminogen would be controlled by the accessibility of plasminogen for activation rather than by the concentration of u-PAR (the latter may act to localize proteolysis to appropriate domains on the surface of the cell). PMID:7639718

  7. Overexpression of urokinase-type plasminogen activator in transgenic mice is correlated with impaired learning.

    PubMed Central

    Meiri, N; Masos, T; Rosenblum, K; Miskin, R; Dudai, Y

    1994-01-01

    Transgenic mice designated alpha MUPA overproduce in the brain murine urokinase-type plasminogen activator (uPA), an extracellular protease implicated in tissue remodeling. We have now localized, by in situ hybridization, extensive signal of uPA mRNA in the alpha MUPA cortex, hippocampus, and amygdala, sites that were not labeled in counterpart wild-type mice. Furthermore, biochemical measurements reveal a remarkably high level of enzymatic activity of uPA in the cortex and hippocampus of alpha MUPA compared with wild-type mice. We have used the alpha MUPA mice to examine whether the abnormal level of uPA in the cortex and the limbic system affects learning ability. We report that alpha MUPA mice perform poorly in tasks of spatial, olfactory, and taste-aversion learning, while displaying normal sensory and motor capabilities. Our results suggest that uPA is involved in neural processes subserving a variety of learning types. Images PMID:8159723

  8. Proteolytic cleavage of the urokinase receptor substitutes for the agonist-induced chemotactic effect.

    PubMed Central

    Resnati, M; Guttinger, M; Valcamonica, S; Sidenius, N; Blasi, F; Fazioli, F

    1996-01-01

    Physiological concentrations of urokinase plasminogen activator (uPA) stimulated a chemotactic response in human monocytic THP-1 through binding to the urokinase receptor (uPAR). The effect did not require the protease moiety of uPA, as stimulation was achieved also with the N-terminal fragment (ATF), while the 33 kDa low molecular weight uPA was ineffective. Co-immunoprecipitation experiments showed association of uPAR with intracellular kinase(s), as demonstrated by in vitro kinase assays. Use of specific antibodies identified p56/p59hck as a kinase associated with uPAR in THP-1 cell extracts. Upon addition of ATF, p56/p59hck activity was stimulated within 2 min and returned to normal after 30 min. Since uPAR lacks an intracellular domain capable of interacting with intracellular kinase, activation of p56/p59hck must require a transmembrane adaptor. Evidence for this was strongly supported by the finding that a soluble form of uPAR (suPAR) was capable of inducing chemotaxis not only in THP-1 cells but also in cells lacking endogenous uPAR (IC50, 5 pM). However, activity of suPAR require chymotrypsin cleavage between the N-terminal domain D1 and D2 + D3. Chymotrypsin-cleaved suPAR also induced activation of p56/p59hck in THP-1 cells, with a time course comparable with ATF. Our data show that uPA-induced signal transduction takes place via uPAR, involves activation of intracellular tyrosine kinase(s) and requires an as yet undefined adaptor capable of connecting the extracellular ligand binding uPAR to intracellular transducer(s). Images PMID:8612581

  9. Purification of rabbit kidney cytokinase and a comparison of its properties with human urokinase

    PubMed Central

    Ali, S. Y.; Evans, Lois

    1968-01-01

    1. The cytokinase (tissue activator of plasminogen) content of several mammalian tissues was evaluated by a quantitative casein hydrolysis method. 2. An alkaline (pH10·5) extraction of cytokinase from rabbit kidney lysosome–microsome fraction, followed by chromatography on DEAE-cellulose at pH7·6 with stepwise or linear increase in concentration of phosphate buffer, gave an 86-fold purification of the enzyme. The purified material was non-proteolytic against casein and heated fibrin and was freeze-dried without significant loss of activity or solubility. 3. Cytokinase is a protein with E0·1%1cm.=0·87 at 280mμ, and does not possess sufficient hexose or sialic acid to be classified as a glycoprotein. It has S20,w 2·9–3·1s and molecular weight 50000 when measured on a calibrated Sephadex G-100 column. It has an isoelectric point between pH8 and pH9, and is maximally active and stable at pH8·5. It is inactivated by heat at 78°. 4. Cytokinase and human urokinase have the same Km value and are inhibited in a partially competitive manner by ∈-aminohexanoic acid and aminomethylcyclohexanecarboxylic acid. They are also inhibited by cysteine and arginine, but are unaffected by iodoacetamide and p-chloromercuribenzoate. 5. On the basis of this and other evidence it is suggested that rabbit kidney cytokinase and human urokinase are similar, if not identical, enzymes. PMID:5641883

  10. Urokinase Receptors Promote β1 Integrin Function through Interactions with Integrin α3β1

    PubMed Central

    Wei, Ying; Eble, Johannes A.; Wang, Zemin; Kreidberg, Jordan A.; Chapman, Harold A.

    2001-01-01

    The urokinase receptor (uPAR) is linked to cellular migration through its capacity to promote pericellular proteolysis, regulate integrin function, and mediate cell signaling in response to urokinase (uPA) binding. The mechanisms for these activities remain incompletely defined, although uPAR was recently identified as a cis-acting ligand for the β2 integrin CD11b/CD18 (Mac-1). Here we show that a major β1 integrin partner for uPAR/uPA signaling is α3. In uPAR-transfected 293 cells uPAR complexed (>90%) with α3β1 and antibodies to α3 blocked uPAR-dependent vitronectin (Vn) adhesion. Soluble uPAR bound to recombinant α3β1 in a uPA-dependent manner (Kd < 20 nM) and binding was blocked by a 17-mer α3β1 integrin peptide (α325) homologous to the CD11b uPAR-binding site. uPAR colocalized with α3β1 in MDA-MB-231 cells and uPA (1 nM) enhanced spreading and focal adhesion kinase phosphorylation on fibronectin (Fn) or collagen type I (Col) in a pertussis toxin- and α325-sensitive manner. A critical role of α3β1 in uPA signaling was verified by studies of epithelial cells from α3-deficient mice. Thus, uPAR preferentially complexes with α3β1, promoting direct (Vn) and indirect (Fn, Col) pathways of cell adhesion, the latter a heterotrimeric G protein-dependent mechanism of signaling between α3β1 and other β1 integrins. PMID:11598185

  11. Ligand Binding Alters Dimerization and Sequestering of Urokinase Receptors in Raft-Mimicking Lipid Mixtures

    PubMed Central

    Ge, Yifan; Siegel, Amanda P.; Jordan, Rainer; Naumann, Christoph A.

    2014-01-01

    Lipid heterogeneities, such as lipid rafts, are widely considered to be important for the sequestering of membrane proteins in plasma membranes, thereby influencing membrane protein functionality. However, the underlying mechanisms of such sequestration processes remain elusive, in part, due to the small size and often transient nature of these functional membrane heterogeneities in cellular membranes. To overcome these challenges, here we report the sequestration behavior of urokinase receptor (uPAR), a glycosylphosphatidylinositol-anchored protein, in a planar model membrane platform with raft-mimicking lipid mixtures of well-defined compositions using a powerful optical imaging platform consisting of confocal spectroscopy XY-scans, photon counting histogram, and fluorescence correlation spectroscopy analyses. This methodology provides parallel information about receptor sequestration, oligomerization state, and lateral mobility with single molecule sensitivity. Most notably, our experiments demonstrate that moderate changes in uPAR sequestration are not only associated with modifications in uPAR dimerization levels, but may also be linked to ligand-mediated allosteric changes of these membrane receptors. Our data show that these modifications in uPAR sequestration can be induced by exposure to specific ligands (urokinase plasminogen activator, vitronectin), but not via adjustment of the cholesterol level in the planar model membrane system. Good agreement of our key findings with published results on cell membranes confirms the validity of our model membrane approach. We hypothesize that the observed mechanism of receptor translocation in the presence of raft-mimicking lipid mixtures is also applicable to other glycosylphosphatidylinositol-anchored proteins. PMID:25418095

  12. Conformation of one- and two-chain high molecular weight urokinase analyzed by small-angle neutron scattering and vacuum ultraviolet circular dichroism

    SciTech Connect

    Mangel, W.F.; Lin, B.H.; Ramakrishnan, V. )

    1991-05-25

    The structures of one- and two-chain high molecular weight human urokinase were analyzed by small-angle neutron scattering and vacuum ultraviolet circular dichroism. Both one- and two-chain high molecular weight urokinases exhibited a radius of gyration of 31 A and a maximum dimension of 90 A. Neither parameter was affected by the presence of lysine sufficient to saturate all the lysine-binding sites in human plasminogen. These physical parameters are consistent with the sedimentation coefficient of high molecular weight urokinase and indicate that both proteins are highly asymmetric. Neither protein contained much alpha-helix or parallel beta-sheet. Most of the secondary structure was in the form of antiparallel beta-sheet and beta-turns, very similar to the secondary structure of plasminogen. The macroscopic kinetic constants, Km and kcat, for the hydrolysis of (pyroGlu-Gly-Arg-NH)2-rhodamine by two-chain high molecular weight urokinase and low molecular weight urokinase which lacks the epidermal growth factor and kringle domains were similar. These structural and kinetic data are consistent with the domains in both forms of urokinase being independent structural and functional units.

  13. Successful lung transplantation after donor lung reconditioning with urokinase in ex vivo lung perfusion system.

    PubMed

    Inci, Ilhan; Yamada, Yoshito; Hillinger, Sven; Jungraithmayr, Wolfgang; Trinkwitz, Michael; Weder, Walter

    2014-11-01

    Acute pulmonary embolism is considered a contraindication to lung donation for transplantation as it might result in graft dysfunction. Ex vivo lung perfusion (EVLP) is a novel method to assess and recondition a questionable donor graft before transplantation. In this report we present a case of successful bilateral lung transplant after donor lung assessment and treatment with a fibrinolytic agent, urokinase, during EVLP. PMID:25441801

  14. In vitro inhibition of human malignant brain tumour cell line proliferation by anti-urokinase-type plasminogen activator monoclonal antibodies.

    PubMed Central

    Abaza, M. S.; Shaban, F. A.; Narayan, R. K.; Atassi, M. Z.

    1998-01-01

    A brain tumour-associated marker, urokinase (UK), was investigated using rabbit anti-UK polyclonal and murine anti-UK monoclonal antibodies, which were prepared by immunization with low molecular weight UK (LMW-UK) and high molecular weight urokinase (HMW-UK) synthetic peptide respectively. The polyclonal antibody cross-reacted with both LMW-UK and HMW-UK, whereas the murine MAbs were specific for HMW-UK. These immunological probes were used to study urokinase in glioma extracts, tissues, sera and cell lines that had been prepared from primary cultures of freshly dissected gliomas. Radioimmunoassays showed that glioma extracts had much higher level (5- to 44-fold) of UK than normal human brain extracts. This result was confirmed by immunoblotting of electrophoresis gels of glioma and human brain extracts. Immunohistochemical study using anti-UK MAb demonstrated much higher levels of UK in glioma tissue than normal brain tissue. Immunohistochemical study using anti-UK MAbs localized UK on the cell surface of glioma cells. Anti-UK MAbs inhibited the proliferation of AA cell lines and GB cell lines (50% to > 90%) and exerted minor effects (< or = 20%) on normal human liver, intestine and lymphocyte cell lines. Taken together, these results suggest that anti-UK MAbs may have therapeutic potential for human gliomas and cancer metastasis. Images Figure 2 Figure 3 PMID:9862567

  15. Targeting of peptide conjugated magnetic nanoparticles to urokinase plasminogen activator receptor (uPAR) expressing cells

    NASA Astrophysics Data System (ADS)

    Hansen, Line; Unmack Larsen, Esben Kjær; Nielsen, Erik Holm; Iversen, Frank; Liu, Zhuo; Thomsen, Karen; Pedersen, Michael; Skrydstrup, Troels; Nielsen, Niels Chr.; Ploug, Michael; Kjems, Jørgen

    2013-08-01

    Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific targeting peptide onto polyethylene glycol (PEG) coated USPIO nanoparticles by click chemistry resulted in a five times higher uptake in vitro in a uPAR positive cell line compared to nanoparticles carrying a non-binding control peptide. In accordance with specific receptor-mediated recognition, a low uptake was observed in the presence of an excess of ATF, a natural ligand for uPAR. The uPAR specific magnetic nanoparticles can potentially provide a useful supplement for tumor patient management when combined with MRI and drug delivery.Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific

  16. Single Amino Acid Substitutions in the Chemotactic Sequence of Urokinase Receptor Modulate Cell Migration and Invasion

    PubMed Central

    Franco, Paola; Pavone, Vincenzo; Mugione, Pietro; Di Carluccio, Gioconda; Masucci, Maria Teresa; Arra, Claudio; Pirozzi, Giuseppe; Stoppelli, Maria Patrizia; Carriero, Maria Vincenza

    2012-01-01

    The receptor for urokinase-type plasminogen activator (uPAR) plays an important role in controlling cell migration. uPAR binds urokinase and vitronectin extracellular ligands, and signals in complex with transmembrane receptors such as Formyl-peptide Receptors (FPR)s and integrins. Previous work from this laboratory has shown that synthetic peptides, corresponding to the uPAR88–92 chemotactic sequence, when carrying the S90P or S90E substitutions, up- or down-regulate cell migration, respectively. To gain mechanistic insights into these opposite cell responses, the functional consequences of S90P and S90E mutations in full-length uPAR were evaluated. First, (HEK)-293 embryonic kidney cells expressing uPARS90P exhibit enhanced FPR activation, increased random and directional cell migration, long-lasting Akt phosphorylation, and increased adhesion to vitronectin, as well as uPAR/vitronectin receptor association. In contrast, the S90E substitution prevents agonist-triggered FPR activation and internalization, decreases binding and adhesion to vitronectin, and inhibits uPAR/vitronectin receptor association. Also, 293/uPARS90P cells appear quite elongated and their cytoskeleton well organized, whereas 293/uPARS90E cells assume a large flattened morphology, with random orientation of actin filaments. Interestingly, when HT1080 cells co-express wild type uPAR with uPAR S90E, the latter behaves as a dominant-negative, impairing uPAR-mediated signaling and reducing cell wound repair as well as lung metastasis in nude mice. In contrast, signaling, wound repair and in vivo lung metastasis of HT1080 cells bearing wild type uPAR are enhanced when they co-express uPARS90P. In conclusion, our findings indicate that Ser90 is a critical residue for uPAR signaling and that the S90P and S90E exert opposite effects on uPAR activities. These findings may be accommodated in a molecular model, in which uPARS90E and uPARS90P are forced into inactive and active forms, respectively

  17. Posttranscriptional regulation of urokinase receptor mRNA: identification of a novel urokinase receptor mRNA binding protein in human mesothelioma cells.

    PubMed Central

    Shetty, S; Kumar, A; Idell, S

    1997-01-01

    Treatment of human pleural mesothelioma (MS-1) cells with phorbol myristate acetate (PMA) and cycloheximide results in 17- and 10-fold, respectively, increases in steady-state expression of urokinase-type plasminogen activator receptor (uPAR) mRNA. Studies of transcriptional inhibition by actinomycin D showed four- and sixfold extensions of uPAR mRNA half-life in MS-1 cells treated with PMA and cycloheximide, respectively, suggesting that uPAR gene expression involves a posttranscriptional regulatory mechanism. Using gel mobility shift and UV cross-linking assays, we identified a 50-kDa uPAR mRNA binding protein (uPAR mRNABp) that selectively bound to a 51-nucleotide (nt) fragment of mRNA corresponding to the uPAR coding region. We investigated the possibility that this 51-nt protein binding fragment of uPAR mRNA contains regulatory information for message stability. Chimeric beta-globin/uPAR/beta-globin mRNA containing the 51-nt protein binding fragment was able to destabilize otherwise stable beta-globin mRNA. Conversely, a control chimeric beta-globin/uPAR/beta-globin mRNA containing a 51-nt fragment of the uPAR coding region that does not bind uPAR mRNABp was stable under identical conditions. Binding of uPAR mRNABp to uPAR mRNA was abolished after treatment with cycloheximide and rapidly down-regulated by PMA. These data suggest that the 51-nt protein binding fragment of uPAR mRNA may be involved in mRNA turnover as well as in cycloheximide-induced uPAR message stabilization. Our results indicate a novel mechanism of uPAR gene regulation in which cis elements within a 51-nt coding region interact with a uPAR mRNABp to regulate uPAR message stability. PMID:9032234

  18. Percutaneous treatment of intrabdominal abscess: urokinase versus saline serum in 100 cases using two surgical scoring systems in a randomized trial.

    PubMed

    Laborda, A; De Gregorio, M A; Miguelena, J M; Medrano, J; Gómez-Arrue, J; Serrano, C; de Blas, I; Gimenez, M; D'Agostino, H

    2009-07-01

    The purpose of this study was to assess whether regular instillation of urokinase during abscess drainage leads to an improved outcome compared to saline irrigation alone. One hundred patients referred for image-guided abdominal abscess drainage were randomized between thrice daily urokinase instillation or saline irrigation alone. At the end of the study, patient medical records were reviewed to determine drainage, study group, Altona (PIA II) and Mannheim (MPI) scoring, duration of drainage, procedure-related complications, hospital stay duration, and clinical outcome. The technical success rate of the percutaneous abscess drainage was 100%. The success or failure of abscess remission did not differ significantly between groups (success rate of 91.5% in the urokinase group vs. 88.8% in the saline group; failure rate was of 8.5 vs. 21.2%, respectively); however, days of drainage, main hospital stay, and overall costs were significantly reduced in patients treated with urokinase compared to the control group (P < 0.05). No adverse effects from urokinase were observed. Surgical scores were a useful homogeneity factor, and MPI showed a good correlation with prognosis, while PIA results did not have a significant correlation. For drainage of complex abscesses (loculations, hemorrhage, viscous material), fibrinolytics safely accelerate drainage and recovery, reducing the length of the hospital stay and, therefore, the total cost. PMID:19190912

  19. The steady states and dynamics of urokinase-mediated plasmin activation.

    PubMed

    Venkatraman, Lakshmi; Yu, Hanry; Bhowmick, Sourav S; Dewey, Forbes; Tucker-Kellogg, Lisa

    2010-01-01

    Plasmin and urokinase-type plasminogen activator (uPA) are ubiquitous proteases regulating the extracellular environment. They can activate each other via proteolytic cleavage, suggesting the potential for complex dynamic behaviors that could be elucidated by computational modeling. Ordinary differential equations are constructed to model the activation dynamics of plasminogen into plasmin, and single-chain uPA (scUPA) into two-chain uPA (tcUPA). Computational simulations and phase plane analysis reveal two stable steady states for the activation of each protein. Bifurcation analysis shows the in silico system to be bistable. Cell-free experiments verify the system to have ultrasensitive activation behavior, where scUPA is the stimulus and plasmin the output. Furthermore, two significantly different steady states could be seen in vitro for the same stimulus levels, depending on the initial activation level of the plasmin. The switch-like dynamics of the uPA-plasmin system could have potential relevance to many normal and disease processes including angiogenesis, migration and metastasis, wound healing and fibrosis. PMID:19908371

  20. Electroanalysis of pM-levels of urokinase plasminogen activator in serum by phosphorothioated RNA aptamer.

    PubMed

    Jarczewska, Marta; Kékedy-Nagy, László; Nielsen, Jesper S; Campos, Rui; Kjems, Jørgen; Malinowska, Elżbieta; Ferapontova, Elena E

    2015-06-01

    Protein biomarkers of cancer allow a dramatic improvement in cancer diagnostics as compared to the traditional histological characterisation of tumours by enabling a non-invasive analysis of cancer development and treatment. Here, an electrochemical label-free assay for urokinase plasminogen activator (uPA), a universal biomarker of several cancers, has been developed based on the recently selected uPA-specific fluorinated RNA aptamer, tethered to a gold electrode via a phosphorothioated dA tag, and soluble redox indicators. The binding properties of the uPA-aptamer couple and interference from the non-specific adsorption of bovine serum albumin (BSA) were modulated by the electrode surface charge. A nM uPA electroanalysis at positively charged surfaces, complicated by the competitive adsorption of BSA, was tuned to the pM uPA analysis at negative surface charges of the electrode, being improved in the presence of negatively charged BSA. The aptamer affinity for uPA displayed via the binding/dissociation constant relationship correspondingly increased, ca. three orders of magnitude, from 0.441 to 367. Under optimal conditions, the aptasensor allowed 10(-12)-10(-9) M uPA analysis, also in serum, being practically useful for clinical applications. The proposed strategy for optimization of the electrochemical protein sensing is of particular importance for the assessment and optimization of in vivo protein ligand binding by surface-tethered aptamers. PMID:25620243

  1. Tyk2 mediates effects of urokinase on human vascular smooth muscle cell growth

    SciTech Connect

    Patecki, Margret; Schaewen, Markus von; Tkachuk, Sergey; Jerke, Uwe; Dietz, Rainer; Dumler, Inna; Kusch, Angelika . E-mail: angelika.kusch@charite.de

    2007-08-03

    The urokinase (uPA)/uPA receptor (uPAR) system plays a role in the response of the vessel wall to injury, presumably by modulating vascular smooth muscle cell (VSMC) functional behaviour. The Jak/Stat signaling pathway has been implicated to mediate the uPA/uPAR-directed cell migration and proliferation in VSMC. We have therefore investigated the underlying molecular mechanisms, which remained not completely understood. In particular, we aimed at identification of the kinase involved in the signaling cascade leading to Stat1 phosphorylation by uPA and its impact on VSMC growth. We performed expression in VSMC of kinase-deficient mutant forms of the Janus kinases Jak1 and Tyk2 and used different cell culture models imitating the response to vascular injury. We provide evidence that Tyk2, but not Jak1, mediates uPA-induced Stat1 phosphorylation and VSMC growth inhibition and suggest a novel function for Tyk2 as an important modulator of the uPA-directed VSMC functional behaviour at the place of injury.

  2. Urokinase links plasminogen activation and cell adhesion by cleavage of the RGD motif in vitronectin.

    PubMed

    De Lorenzi, Valentina; Sarra Ferraris, Gian Maria; Madsen, Jeppe B; Lupia, Michela; Andreasen, Peter A; Sidenius, Nicolai

    2016-07-01

    Components of the plasminogen activation system including urokinase (uPA), its inhibitor (PAI-1) and its cell surface receptor (uPAR) have been implicated in a wide variety of biological processes related to tissue homoeostasis. Firstly, the binding of uPA to uPAR favours extracellular proteolysis by enhancing cell surface plasminogen activation. Secondly, it promotes cell adhesion and signalling through binding of the provisional matrix protein vitronectin. We now report that uPA and plasmin induces a potent negative feedback on cell adhesion through specific cleavage of the RGD motif in vitronectin. Cleavage of vitronectin by uPA displays a remarkable receptor dependence and requires concomitant binding of both uPA and vitronectin to uPAR Moreover, we show that PAI-1 counteracts the negative feedback and behaves as a proteolysis-triggered stabilizer of uPAR-mediated cell adhesion to vitronectin. These findings identify a novel and highly specific function for the plasminogen activation system in the regulation of cell adhesion to vitronectin. The cleavage of vitronectin by uPA and plasmin results in the release of N-terminal vitronectin fragments that can be detected in vivo, underscoring the potential physiological relevance of the process. PMID:27189837

  3. Terminalia catappa attenuates urokinase-type plasminogen activator expression through Erk pathways in Hepatocellular carcinoma

    PubMed Central

    2014-01-01

    Background The survival rate of malignant tumors, and especially hepatocellular carcinoma (HCC), has not improved primarily because of uncontrolled metastasis. In our previous studies, we have reported that Terminalia catappa leaf extract (TCE) exerts antimetastasis effects on HCC cells. However, the molecular mechanisms of urokinase-type plasminogen activator (u-PA) in HCC metastasis have not been thoroughly investigated, and remain poorly understood. Methods The activities and protein levels of u-PA were determined by casein zymography and western blotting. Transcriptional levels of u-PA were detected by real-time PCR and promoter assays. Results We found that treatment of Huh7 cells with TCE significantly reduced the activities, protein levels and mRNA levels of u-PA. A chromatin immunoprecipitation (ChIP) assay showed that TCE inhibited the transcription protein of nuclear factors SP-1 and NF-κB. TCE also did inhibit the effects of u-PA by reducing the phosphorylation of ERK1/2 pathway. Conclusions These results show that u-PA expression may be a potent therapeutic target in the TCE-mediated suppression of HCC metastasis. PMID:24886639

  4. Soluble Urokinase Receptors in Focal Segmental Glomerulosclerosis: A Review on the Scientific Point of View

    PubMed Central

    Saleem, Moin A.; Meijers, Björn

    2016-01-01

    Focal segmental glomerulosclerosis (FSGS) is one of the primary glomerular disorders in both children and adults which can progress to end-stage renal failure. Although there are genetic and secondary causes, circulating factors have also been regarded as an important factor in the pathogenesis of FSGS, because about 40% of the patients with FSGS have recurrence after renal transplantation. Soluble urokinase-type plasminogen activator receptor (suPAR) is a soluble form of uPAR, which is a membrane-bound protein linked to GPI in various immunologically active cells, including podocytes. It has recently been suggested as a potential circulating factor in FSGS by in vitro podocyte experiments, in vivo mice models, and human studies. However, there have also been controversies on this issue, because subsequent studies showed conflicting results. suPAR levels were also increased in patients with other glomerular diseases and were inversely correlated with estimated glomerular filtration rate. Nevertheless, there has been no balanced review on this issue. In this review, we compare the conflicting data on the involvement of suPAR in the pathogenesis of FSGS and shed light on interpretation by taking into account many points and the potential variables and confounders influencing serum suPAR levels. PMID:27504461

  5. Density enhanced phosphatase-1 down-regulates urokinase receptor surface expression in confluent endothelial cells

    PubMed Central

    Brunner, Patrick M.; Heier, Patricia C.; Mihaly-Bison, Judit; Priglinger, Ute; Binder, Bernd R.

    2011-01-01

    VEGF165, the major angiogenic growth factor, is known to activate various steps in proangiogenic endothelial cell behavior, such as endothelial cell migration and invasion, or endothelial cell survival. Thereby, the urokinase-type plasminogen activator (uPA) system has been shown to play an essential role not only by its proteolytic capacities, but also by induction of intracellular signal transduction. Therefore, expression of its cell surface receptor uPAR is thought to be an essential regulatory mechanism in angiogenesis. We found that uPAR expression on the surface of confluent endothelial cells was down-regulated compared with subconfluent proliferating endothelial cells. Regulation of uPAR expression was most probably affected by extracellular signal-regulated kinase 1/2 (ERK1/2) activation, a downstream signaling event of the VEGF/VEGF-receptor system. Consistently, the receptor-like protein tyrosine phosphatase DEP-1 (density enhanced phosphatase-1/CD148), which is abundantly expressed in confluent endothelial cells, inhibited the VEGF-dependent activation of ERK1/2, leading to down-regulation of uPAR expression. Overexpression of active ERK1 rescued the DEP-1 effect on uPAR. That DEP-1 plays a biologic role in angiogenic endothelial cell behavior was demonstrated in endothelial cell migration, proliferation, and capillary-like tube formation assays in vitro. PMID:21304107

  6. [Preparation of novel magnetic dextran affinity adsorbents and their application to purify urokinase].

    PubMed

    Dong, Y S; Liang, F; Yu, X Y; Guo, L A; Chang, J H

    2001-01-01

    The reverse phase suspension and embedment technique were adopted to prepare magnetic dextran microsphere (MDMS). The dispersion medium was mixture of some organic solvents. Span-80 was used as stabilizer. The aqueous dextran with magnetic fluid was suspended in dispersion medium with epichlorohydrin as cross-linking reagent. The mixture was stirred for 30 minutes at room temperature and then heated at 70 degrees C for 4 hours, MDMS was thus obtained. MDMS was activated by epichlorohydrin on which 6-aminohexanoic acid, glycine or ethylene diamine was bonded as spacers. Then it was coupled with p-aminobenzamide, L-arginine methyl ester or guanidohexanoic acid and five magnetic affinity adsorbents were prepared. The MDMS was polydisperse particles with the size of 50-300 meshes and the content of Fe3O4 was about 6.2 per cent in the MDMS. Influence of some parameters such as viscosity and density of organic phase, the volume ratio of organic and aqueous phase, the quantity of surfactant and stirring speed on preparing MDMS was studied. Magnetic affinity adsorbents were used to purify crude urokinase in a bath mode and the effect of coupling reagents and ligands on results of purification was discussed. The bioactivity recovery was 40.0 to 60.7 per cent, the purification-fold was between 14.9 and 32.8, and the adsorptive capacity varies from 89 mg to 121 mg per milliliter of adsorbent. PMID:12541840

  7. Challenges for drug discovery - a case study of urokinase receptor inhibition

    PubMed Central

    Chen, Zhuo; Lin, Lin; Huai, Qing; Huang, Mingdong

    2009-01-01

    Urokinase receptor (uPAR) is a widely recognized target for potential treatment of cancer. The development of uPAR inhibitors has been going on for over a decade. Despite the identification and validation of many highly potent hits using screening or medicinal approaches, none of them has been moved further along the drug discovery pipeline. The development of uPAR inhibitors exemplifies several challenges now faced by drug discovery. These include 1) hydrophobicity and thus poor bioavailability of the inhibitors from screening approaches; 2) specificity of the inhibitor, where a peptidyl inhibitor causes conformational change of the receptor; 3) species specificity, where some inhibitors developed based on the human receptor do not inhibit the murine receptor and thus cannot be validated in mouse models. The recently determined crystal structures of uPAR in complex with its ligand or inhibitor not only provide the structural insight to understand these challenges but also offer a potential solution for further inhibitor development and thus illustrate the importance of structural information in facilitating drug discovery. PMID:20025562

  8. Regulation of plasminogen activator inhibitor-1 and urokinase by hyaluronan fragments in mouse macrophages.

    PubMed

    Horton, M R; Olman, M A; Bao, C; White, K E; Choi, A M; Chin, B Y; Noble, P W; Lowenstein, C J

    2000-10-01

    Pulmonary inflammation and fibrosis are characterized by increased turnover and production of the extracellular matrix as well as an impairment of lung fibrinolytic activity. Although fragments of the extracellular matrix component hyaluronan induce macrophage production of inflammatory mediators, the effect of hyaluronan on the fibrinolytic mediators plasminogen activator inhibitor (PAI)-1 and urokinase-type plasminogen activator (uPA) is unknown. This study demonstrates that hyaluronan fragments augment steady-state mRNA, protein, and inhibitory activity of PAI-1 as well as diminish the baseline levels of uPA mRNA and inhibit uPA activity in an alveolar macrophage cell line. Hyaluronan fragments alter macrophage expression of PAI-1 and uPA at the level of gene transcription. Similarly, hyaluronan fragments augment PAI-1 and diminish uPA mRNA levels in freshly isolated inflammatory alveolar macrophages from bleomycin-treated rats. These data suggest that hyaluronan fragments influence alveolar macrophage expression of PAI-1 and uPA and may be a mechanism for regulating fibrinolytic activity during lung inflammation. PMID:11000131

  9. A reassessment of soluble urokinase-type plasminogen activator receptor in glomerular disease

    PubMed Central

    Spinale, Joann M.; Mariani, Laura H.; Kapoor, Shiv; Zhang, Jidong; Weyant, Robert; Song, Peter X.; Wong, Hetty N.; Troost, Jonathan P.; Gadegbeku, Crystal A.; Gipson, Debbie S.; Kretzler, Matthias; Nihalani, Deepak; Holzman, Lawrence B.

    2014-01-01

    It has been suggested that soluble urokinase receptor (suPAR) is a causative circulating factor for and a biomarker of focal and segmental glomerulosclerosis (FSGS). Here we undertook validation of these assumptions in both mouse and human models. Injection of recombinant suPAR in wild-type mice did not induce proteinuria within 24 hours. Moreover, a disease phenotype was not seen in an inducible transgenic mouse model that maintained elevated suPAR concentrations for 6 weeks. Plasma and urine suPAR concentrations were evaluated as clinical biomarkers in 241 patients with glomerular disease from the prospective, longitudinal multi-center observational NEPTUNE cohort. The serum suPAR concentration at baseline inversely correlated with estimated glomerular filtration rate (eGFR) and the urine suPAR/creatinine ratio positively correlated with the urine protein/creatinine ratio. After adjusting for eGFR and urine protein, neither the serum nor urine suPAR level was an independent predictor of FSGS histopathology. A multivariable mixed-effects model of longitudinal data evaluated the association between the change in serum suPAR concentration from baseline with eGFR. After adjusting for baseline suPAR concentration, age, gender, proteinuria and time, the change in suPAR from baseline was associated with eGFR, but this association was not different for patients with FSGS as compared to other diagnoses. Thus, these results do not support a pathological role for suPAR in FSGS. PMID:25354239

  10. A reassessment of soluble urokinase-type plasminogen activator receptor in glomerular disease.

    PubMed

    Spinale, Joann M; Mariani, Laura H; Kapoor, Shiv; Zhang, Jidong; Weyant, Robert; Song, Peter X; Wong, Hetty N; Troost, Jonathan P; Gadegbeku, Crystal A; Gipson, Debbie S; Kretzler, Matthias; Nihalani, Deepak; Holzman, Lawrence B

    2015-03-01

    It has been suggested that soluble urokinase receptor (suPAR) is a causative circulating factor for and a biomarker of focal and segmental glomerulosclerosis (FSGS). Here we undertook validation of these assumptions in both mouse and human models. Injection of recombinant suPAR in wild-type mice did not induce proteinuria within 24 h. Moreover, a disease phenotype was not seen in an inducible transgenic mouse model that maintained elevated suPAR concentrations for 6 weeks. Plasma and urine suPAR concentrations were evaluated as clinical biomarkers in 241 patients with glomerular disease from the prospective, longitudinal multicenter observational NEPTUNE cohort. The serum suPAR concentration at baseline inversely correlated with estimated glomerular filtration rate (eGFR) and the urine suPAR/creatinine ratio positively correlated with the urine protein/creatinine ratio. After adjusting for eGFR and urine protein, neither the serum nor urine suPAR level was an independent predictor of FSGS histopathology. A multivariable mixed-effects model of longitudinal data evaluated the association between the change in serum suPAR concentration from baseline with eGFR. After adjusting for baseline suPAR concentration, age, gender, proteinuria, and time, the change in suPAR from baseline was associated with eGFR, but this association was not different for patients with FSGS as compared with other diagnoses. Thus these results do not support a pathological role for suPAR in FSGS. PMID:25354239

  11. Full-length soluble urokinase plasminogen activator receptor down-modulates nephrin expression in podocytes.

    PubMed

    Alfano, Massimo; Cinque, Paola; Giusti, Guido; Proietti, Silvia; Nebuloni, Manuela; Danese, Silvio; D'Alessio, Silvia; Genua, Marco; Portale, Federica; Lo Porto, Manuela; Singhal, Pravin C; Rastaldi, Maria Pia; Saleem, Moin A; Mavilio, Domenico; Mikulak, Joanna

    2015-01-01

    Increased plasma level of soluble urokinase-type plasminogen activator receptor (suPAR) was associated recently with focal segmental glomerulosclerosis (FSGS). In addition, different clinical studies observed increased concentration of suPAR in various glomerular diseases and in other human pathologies with nephrotic syndromes such as HIV and Hantavirus infection, diabetes and cardiovascular disorders. Here, we show that suPAR induces nephrin down-modulation in human podocytes. This phenomenon is mediated only by full-length suPAR, is time-and dose-dependent and is associated with the suppression of Wilms' tumor 1 (WT-1) transcription factor expression. Moreover, an antagonist of αvβ3 integrin RGDfv blocked suPAR-induced suppression of nephrin. These in vitro data were confirmed in an in vivo uPAR knock out Plaur(-/-) mice model by demonstrating that the infusion of suPAR inhibits expression of nephrin and WT-1 in podocytes and induces proteinuria. This study unveiled that interaction of full-length suPAR with αvβ3 integrin expressed on podocytes results in down-modulation of nephrin that may affect kidney functionality in different human pathologies characterized by increased concentration of suPAR. PMID:26380915

  12. Urokinase-type plasminogen activator receptor signaling is critical in nasopharyngeal carcinoma cell growth and metastasis.

    PubMed

    Bao, Ying-Na; Cao, Xue; Luo, Dong-Hua; Sun, Rui; Peng, Li-Xia; Wang, Lin; Yan, Yong-Pan; Zheng, Li-Sheng; Xie, Ping; Cao, Yun; Liang, Ying-Ying; Zheng, Fang-Jing; Huang, Bi-Jun; Xiang, Yan-Qun; Lv, Xing; Chen, Qiu-Yan; Chen, Ming-Yuan; Huang, Pei-Yu; Guo, Ling; Mai, Hai-Qiang; Guo, Xiang; Zeng, Yi-Xin; Qian, Chao-Nan

    2014-01-01

    Nasopharyngeal carcinoma (NPC) is one of the most common malignancies in southern China and Southeast Asia, with the highest metastasis rate among head and neck cancers. The mechanisms underlying NPC progression remain poorly understood. Genome-wide expression profiling on 18 NPC vs. 18 noncancerous nasopharyngeal tissues together with GeneGo pathway analysis and expression verification in NPC cells and tissues revealed a potential role of urokinase-type plasminogen activator receptor (uPAR) in NPC progression, which has not been investigated in NPC. We then observed that uPAR expression is increased in poorly differentiated, highly metastatic NPC cells compared with lowly metastatic cells or differentiated NPC cells. In vitro studies demonstrated that uPAR regulates NPC cell growth, colony formation, migration, and invasion and promotes the epithelial-mesenchymal transition (EMT). Additional tumor xenograft and spontaneous metastasis experiments revealed that uPAR promotes NPC cell growth and metastasis in vivo. The JAK-STAT pathway is involved in uPAR-regulated signaling in NPC cells as determined by immunoblotting. Moreover, uPAR-mediated growth and motility is partially abolished upon treatment with the Jak1/Jak2 inhibitor INCB018424. We suppressed uPA expression in uPAR-overexpressing NPC cells and found that uPAR-mediated cellular growth and motility is not exclusively dependent on uPA. In summary, uPAR is a significant regulator of NPC progression and could serve as a promising therapeutic target. PMID:24763226

  13. Cytokines in cerebrospinal fluid of neurosyphilis patients: Identification of Urokinase plasminogen activator using antibody microarrays.

    PubMed

    Lu, Ping; Zheng, Dao-Cheng; Fang, Chang; Huang, Jin-Mei; Ke, Wu-Jian; Wang, Liu-Yuan; Zeng, Wei-Ying; Zheng, He-Ping; Yang, Bin

    2016-04-15

    Little is known regarding protein responses to syphilis infection in cerebrospinal fluid (CSF) of patients presenting with neurosyphilis. Protein and antibody arrays offer a new opportunity to gain insights into global protein expression profiles in these patients. Here we obtained CSF samples from 46 syphilis patients, 25 of which diagnosed as having central nervous system involvement based on clinical and laboratory findings. The CSF samples were then analyzed using a RayBioH L-Series 507 Antibody Array system designed to simultaneously analyze 507 specific cytokines. The results indicated that 41 molecules showed higher levels in patients with neurosyphilis in comparison with patients without neural involvement. For validation by single target ELISA, we selected five of them (MIP-1a, I-TAC/CXCL11, Urokinase plasminogen activator [uPA], and Oncostatin M) because they have previously been found to be involved in central nervous system (CNS) disorders. The ELISA tests confirmed that uPA levels were significantly higher in the CSF of neurosyphilis patients (109.1±7.88pg/ml) versus patients without CNS involvement (63.86±4.53pg/ml, p<0.0001). There was also a clear correlation between CSF uPA levels and CSF protein levels (p=0.0128) as well as CSF-VDRL titers (p=0.0074) used to diagnose neurosyphilis. No significant difference between the two groups of patients, however, was found in uPA levels in the serum, suggesting specific activation of the inflammatory system in the CNS but not the periphery in neurosyphilis patients. We conclude that measurements of uPA levels in CSF may be an additional parameter for diagnosing neurosyphilis. PMID:27049560

  14. Microglia and the urokinase plasminogen activator receptor/uPA system in innate brain inflammation.

    PubMed

    Cunningham, Orla; Campion, Suzanne; Perry, V Hugh; Murray, Carol; Sidenius, Nicolai; Docagne, Fabian; Cunningham, Colm

    2009-12-01

    The urokinase plasminogen activator (uPA) receptor (uPAR) is a GPI-linked cell surface protein that facilitates focused plasmin proteolytic activity at the cell surface. uPAR has been detected in macrophages infiltrating the central nervous system (CNS) and soluble uPAR has been detected in the cerebrospinal fluid during a number of CNS pathologies. However, its expression by resident microglial cells in vivo remains uncertain. In this work, we aimed to elucidate the murine CNS expression of uPAR and uPA as well as that of tissue plasminogen activator and plasminogen activator inhibitor 1 (PAI-1) during insults generating distinct and well-characterized inflammatory responses; acute intracerebral lipopolysaccharide (LPS), acute kainate-induced neurodegeneration, and chronic neurodegeneration induced by prion disease inoculation. All three insults induced marked expression of uPAR at both mRNA and protein level compared to controls (naïve, saline, or control inoculum-injected). uPAR expression was microglial in all cases. Conversely, uPA transcription and activity was only markedly increased during chronic neurodegeneration. Dissociation of uPA and uPAR levels in acute challenges is suggestive of additional proteolysis-independent roles for uPAR. PAI-1 was most highly expressed upon LPS challenge, whereas tissue plasminogen activator mRNA was constitutively present and less responsive to all insults studied. These data are novel and suggest much wider involvement of the uPAR/uPA system in CNS function and pathology than previously supposed. PMID:19459212

  15. Urokinase-type plasminogen activator receptor modulates epileptogenesis in mouse model of temporal lobe epilepsy.

    PubMed

    Ndode-Ekane, Xavier Ekolle; Pitkänen, Asla

    2013-06-01

    Mutation in Plaur gene encoding urokinase-type plasminogen activator receptor (uPAR) results in epilepsy and autistic phenotype in mice. In humans, a single nucleotide polymorphism in PLAUR gene represents a risk for autism spectrum disorders. Importantly, the expression of uPAR is elevated in the brain after various epileptogenic insults like traumatic brain injury and status epilepticus. So far, the consequences of altered uPAR expression on brain networks are poorly known. We tested a hypothesis that uPAR regulates post-injury neuronal reorganization and consequent functional outcome, particularly epileptogenesis. Epileptogenesis was induced by intrahippocampal injection of kainate in adult male wild type (Wt) or uPAR knockout (uPAR-/-) mice, and animals were monitored with continuous (24/7) video-electroencephalogram for 30 days. The severity of status epilepticus did not differ between the genotypes. The spontaneous electrographic seizures which developed were, however, longer and their behavioral manifestations were more severe in uPAR-/- than Wt mice. The more severe epilepsy phenotype in uPAR-/- mice was associated with delayed but augmented inflammatory response and more severe neurodegeneration in the hippocampus. Also, the distribution of newly born cells in the dentate gyrus was more scattered, and the recovery of hippocampal blood vessel length from status epilepticus-induced damage was compromised in uPAR-/- mice as compared to Wt mice. Our data demonstrate that a deficiency in uPAR represents a mechanisms which results in the development of a more severe epilepsy phenotype and progressive brain pathology after status epilepticus. We suggest that uPAR represents a rational target for disease-modifying treatments after epileptogenic brain insults. PMID:23263886

  16. Urokinase-coated chitosan nanoparticles for thrombolytic therapy: preparation and pharmacodynamics in vivo.

    PubMed

    Jin, Hai-jiang; Zhang, Hao; Sun, Min-li; Zhang, Bai-gen; Zhang, Ji-wei

    2013-11-01

    Blood reperfusion of affected limbs is the most effective therapy for peripheral vascular thrombotic disease, restoring nutrition and blood flow to threatened tissues. Because it is more cost-effective than other thrombolytics, urokinase (UK) is widely used to treat venous thrombosis in China. However, its use is limited because of the risk of UK-related hemorrhagic complications. UK-coated nanoparticles (NPs) may decrease adverse effects while simultaneously increasing thrombolytic benefits. The aim of this study was to combine the sustained-release properties of NPs with the clinical benefits of catheter-directed thrombolysis (CDT) to create a promising new therapy. NPs were prepared via self-assembled chitosan and tripolyphosphate, introduced into a thrombosis model in New Zealand white rabbits, and the ratio of the residual thrombus cross-sectional area to the vascular cross-sectional area was calculated. The NPs had a drug-bearing efficiency of 14.5 ± 1.3%, an encapsulation efficiency of 94.8 ± 2.1% while the particle size of UK-coated NPs was 236 nm. Transmission electron microscopy results showed that the shape of the NPs were spherical and regular. Whether delivered by intravenation or catheter, UK-coated NPs produced a significant increase in the thrombolytic effect compared with free UK and confirmed the superiority of CDT for improving clot lysis over drug-induced systemic thrombolysis. The intravenous NPs caused an abnormal increase in fibrinogen. In conclusion, a water-soluble UK-WCS-NP suspension with good encapsulation efficiency was easily prepared UK-WCS-NPs were capable of maintaining UK activity, provided sustained-release of UK and exhibited better thrombolytic function than free UK. PMID:23728739

  17. Effect of urokinase-type plasminogen activator system in gastric cancer with peritoneal metastasis

    PubMed Central

    DING, YOUCHENG; ZHANG, HUI; LU, AIGUO; ZHOU, ZHUQING; ZHONG, MINGAN; SHEN, DONGWEI; WANG, XUJING; ZHU, ZHENGGANG

    2016-01-01

    Peritoneal metastasis is a primary cause of mortality in patients with gastric cancer. Urokinase-type plasminogen activator (uPA) has been demonstrated to be associated with tumor cell metastasis through the degradation of the extracellular matrix. The present study aimed to investigate the mechanisms of the uPA system in gastric cancer with peritoneal metastasis. Expression of uPA, uPA receptor (uPAR) and plasminogen activator inhibitor-1 (PAI-1) in four gastric cell lines (AGS, SGC7901, MKN45 and MKN28) was measured by semiquantitative reverse transcription polymerase chain reaction, enzyme-linked immunosorbent assay and western blotting. uPA activity was detected using a uPA activity kit. Peritoneal implantation models of rats were established by injecting four gastric cancer cell lines for the selection of the cancer cells with a high planting potential. Biological behaviors, including adhesion, migration and invasion, were determined using a methyl thiazolyl tetrazolium assay. Expression of the uPA system was observed to be highest in the SGC7901 cells among the four gastric cell lines. uPA activity was observed to be highest in the MKN45 cells and lowest in the AGS cells. Furthermore, peritoneal implantation analysis demonstrated that no peritoneal tumors were identified in the AGS cells, whilst the tumor masses observed in the SGC7901 and MKN45 cells were of different sizes. The survival times of the rats injected with the MKN28 and SGC7901 cells were longer than those of the rats injected with the MKN45 cells. Antibodies for uPA, uPAR and PAI-1 in the uPA system had the ability to inhibit the adhesion, migration and invasion of peritoneal metastasis in the gastric cancer cells. The results of the present study demonstrated that the uPA system was positively associated with peritoneal metastasis in gastric cancer. PMID:27313768

  18. Hypoxia stimulates urokinase receptor expression through a heme protein-dependent pathway.

    PubMed

    Graham, C H; Fitzpatrick, T E; McCrae, K R

    1998-05-01

    Hypoxia underlies a number of biologic processes in which cellular migration and invasion occur. Because earlier studies have shown that the receptor for urokinase-type plasminogen activator (uPAR) may facilitate such events, we studied the effect of hypoxia on the expression of uPAR by first trimester human trophoblasts (HTR-8/SVneo) and human umbilical vein endothelial cells (HUVEC). Compared with control cells cultured under standard conditions (20% O2), HTR-8/SVneo cells and HUVEC cultured in 1% O2 expressed more uPAR, as determined by flow cytometric and [125I]-prourokinase ligand binding analyses. Increased uPAR expression paralleled increases in uPAR mRNA. The involvement of a heme protein in the hypoxia-induced expression of uPAR was suggested by the observations that culture of cells with cobalt chloride, or sodium 4, 5-dihydroxybenzene-1,3-disulfonate (Tiron), an iron-chelating agent, also stimulated uPAR expression, and that the hypoxia-induced uPAR expression was inhibited by adding carbon monoxide to the hypoxic atmosphere. Culture of HTR-8/SVneo cells with vascular endothelial growth factor (VEGF) did not increase uPAR mRNA levels, suggesting that the hypoxia-mediated effect on uPAR expression by these cells did not occur through a VEGF-dependent mechanism. The functional importance of these findings is suggested by the fact that HTR-8/SVneo cells cultured under hypoxia displayed higher levels of cell surface plasminogen activator activity and greater invasion through a reconstituted basement membrane. These results suggest that hypoxia may promote cellular invasion by stimulating the expression of uPAR through a heme protein-dependent pathway. PMID:9558386

  19. Preclinical evaluation of a urokinase plasminogen activator receptor-targeted nanoprobe in rhesus monkeys

    PubMed Central

    Chen, Yushu; Gong, Li; Gao, Ning; Liao, Jichun; Sun, Jiayu; Wang, Yuqing; Wang, Lei; Zhu, Pengjin; Fan, Qing; Wang, Yongqiang Andrew; Zeng, Wen; Mao, Hui; Yang, Lily; Gao, Fabao

    2015-01-01

    Purpose To translate a recombinant peptide containing the amino-terminal fragment (ATF) of urokinase plasminogen activator receptor-targeted magnetic iron oxide (IO) nanoparticles (uPAR-targeted human ATF-IONPs) into clinical applications, we conducted a pilot study to evaluate the toxicity and pharmacokinetics of this nanoparticle in normal rhesus monkeys. Methods We assessed the changes in the following: magnetic resonance imaging (MRI) signals from pretreatment stage to 14 days posttreatment, serum iron concentrations from 5 minutes posttreatment to 12 weeks posttreatment, routine blood examination and serum chemistry analysis results from pretreatment stage to 12 weeks after administration, and results of staining of the liver with Perls’ Prussian Blue and hematoxylin–eosin at 24 hours and 3 months posttreatment in two rhesus monkeys following an intravenous administration of the targeted nanoparticles either with a polyethylene glycol (ATF-PEG-IONP) or without a PEG (ATF-IONP) coating. Results The levels of alkaline phosphatase, alanine transaminase, and direct bilirubin in the two monkeys increased immediately after the administration of the IONPs but returned to normal within 20 days and stayed within the normal reference range 3 months after the injection. The creatinine levels of the two monkeys stayed within the normal range during the study. In addition, red blood cells, white blood cells, hemoglobin level, and platelets remained normal during the 3 months of the study. Conclusion All of the results suggest that a transient injury in terms of normal organ functions, but no microscopic necrotic lesions, was observed at a systemic delivery dose of 5 mg/kg of iron equivalent concentration in the acute phase, and that no chronic toxicity was found 3 months after the injection. Therefore, we conclude that uPAR-targeted IONPs have the potential to be used as receptor-targeted MRI contrasts as well as theranostic agents for the detection and treatment of

  20. A chimeric platelet-targeted urokinase prodrug selectively blocks new thrombus formation

    PubMed Central

    Fuentes, Rudy E.; Zaitsev, Sergei; Ahn, Hyun Sook; Hayes, Vincent; Kowalska, M. Anna; Lambert, Michele P.; Wang, Yuhuan; Siegel, Donald L.; Bougie, Daniel W.; Aster, Richard H.; Myers, Daniel D.; Stepanova, Victoria; Cines, Douglas B.; Muzykantov, Vladimir R.; Poncz, Mortimer

    2015-01-01

    The use of fibrinolytic agents to prevent new thrombus formation is limited by an increased risk of bleeding due to lysis of hemostatic clots that prevent hemorrhage in damaged blood vessels. We sought to develop an agent that provides thromboprophylaxis without carrying a significant risk of causing systemic fibrinolysis or disrupting hemostatic clots. We previously showed that platelet (PLT) α granule–delivered urokinase plasminogen activator (uPA) is highly effective in preventing thrombosis, while being associated with little systemic fibrinolysis or bleeding. Here, we generated a chimeric prodrug composed of a single-chain version of the variable region of an anti-αIIbβ3 mAb fused to a thrombin-activatable, low-molecular-weight pro-uPA (PLT/uPA-T). PLT/uPA-T recognizes human αIIbβ3 on both quiescent and activated platelets and is enzymatically activated specifically by thrombin. We found that this prodrug binds tightly to human platelets even after gel filtration, has a prolonged half-life in mice transgenic for human αIIb compared with that of uPA-T, and prevents clot formation in a microfluidic system. Importantly, in two murine injury models, PLT/uPA-T did not lyse preexisting clots, even when administration was delayed by as little as 10 minutes, while it concurrently prevented the development of nascent thrombi. Thus, PLT/uPA-T represents the prototype of a platelet-targeted thromboprophylactic agent that selectively targets nascent over preexisting thrombi. PMID:26690701

  1. Urokinase, a constitutive component of the inflamed synovial fluid, induces arthritis

    PubMed Central

    Jin, Tao; Tarkowski, Andrej; Carmeliet, Peter; Bokarewa, Maria

    2003-01-01

    Urokinase plasminogen activator (uPA) is an important regulator of fibrinolysis in synovial fluid. An increase of uPA activity and expression of its receptor have been reported in joints of patients with rheumatoid arthritis (RA). The aim of the present study was to assess the arthritogenic capacity of uPA and the mechanisms by which this effect is mediated. uPA was injected into the knee joints of healthy mice, and morphological signs of arthritis were assessed 4 days after the injection. The prerequisite of different leukocyte populations for the development of uPA-triggered arthritis was assessed by selective cell depletion. The inflammatory capacity of uPA was assessed in vitro. Finally, levels of uPA were measured in 67 paired blood and synovial fluid samples from RA patients. The synovial fluid from RA patients displayed higher levels of uPA compared with blood samples. Morphological signs of arthritis were found in 72% of uPA-injected joints compared with in only 18% of joints injected with PBS (P < 0.05). Synovitis was characterised by infiltration of CD4-Mac-1+ mononuclear cells, by the formation of pannus and by occasional cartilage destruction. The absence of monocytes and lymphocytes diminished the frequency of synovitis (P < 0.01), indicating an arthritogenic role of both these leukocyte populations. Synthetic uPA inhibitor downregulated the incidence of uPA-triggered arthritis by 50%. uPA induced arthritis, stimulating the release of proinflammatory cytokines IL-6, IL-1β and tumour necrosis factor alpha. Accumulation of uPA locally in the joint cavity is a typical finding in erosive RA. uPA exerts potent arthritogenic properties and thus may be viewed as one of the essential mediators of joint inflammation. PMID:12716448

  2. Probing Binding and Cellular Activity of Pyrrolidinone and Piperidinone Small Molecules Targeting the Urokinase Receptor

    PubMed Central

    Mani, Timmy; Liu, Degang; Zhou, Donghui; Li, Liwei; Knabe, William Eric; Wang, Fang; Oh, Kyungsoo; Meroueh, Samy O.

    2014-01-01

    The urokinase receptor (uPAR) is a cell-surface protein that is part of an intricate web of transient and tight protein interactions that promote cancer cell invasion and metastasis. Here we evaluate the binding and biological activity of a new class of pyrrolidinone (3) and piperidinone (4) compounds, along with derivatives of previously-identified pyrazole (1) and propylamine (2) compounds. Competition assays revealed that the compounds displaced a fluorescently-labeled peptide (AE147-FAM) with inhibition constant Ki ranging from 6 to 63 μM. Structure-based computational pharmacophore analysis followed by extensive explicit-solvent molecular dynamics simulations and free energy calculations suggested pyrazole-based 1a and piperidinone-based 4 adopt different binding modes, despite their similar two-dimensional structures. In cells, compounds 1b and 1f showed significant inhibition of breast MDA-MB-231 and pancreatic ductal adenocarcinoma (PDAC) cell proliferation, but 4b exhibited no cytotoxicity even at concentrations of 100 μM. 1f impaired MDA-MB-231 invasion, adhesion, and migration in a concentration-dependent manner, while 4b inhibited only invasion. 1f inhibited gelatinase (MMP-9) activity in a concentration-dependent manner, while 4b showed no effect suggesting different mechanisms for inhibition of cell invasion. Signaling studies further highlighted these differences, showing that pyrazole compounds completely inhibited ERK phosphorylation and impaired HIF1α and NF-κB signaling, while pyrrolidinone and piperidinone (3 and 4b) had no effect. Annexin V staining suggested that the effect of pyrazole-based 1f on proliferation was due to cell killing through an apoptotic mechanism. PMID:24115356

  3. Imaging the urokinase plasminongen activator receptor in preclinical breast cancer models of acquired drug resistance.

    PubMed

    LeBeau, Aaron M; Sevillano, Natalia; King, Mandy L; Duriseti, Sai; Murphy, Stephanie T; Craik, Charles S; Murphy, Laura L; VanBrocklin, Henry F

    2014-01-01

    Subtype-targeted therapies can have a dramatic impact on improving the quality and quantity of life for women suffering from breast cancer. Despite an initial therapeutic response, cancer recurrence and acquired drug-resistance are commonplace. Non-invasive imaging probes that identify drug-resistant lesions are urgently needed to aid in the development of novel drugs and the effective utilization of established therapies for breast cancer. The protease receptor urokinase plasminogen activator receptor (uPAR) is a target that can be exploited for non-invasive imaging. The expression of uPAR has been associated with phenotypically aggressive breast cancer and acquired drug-resistance. Acquired drug-resistance was modeled in cell lines from two different breast cancer subtypes, the uPAR negative luminal A subtype and the uPAR positive triple negative subtype cell line MDA-MB-231. MCF-7 cells, cultured to be resistant to tamoxifen (MCF-7 TamR), were found to significantly over-express uPAR compared to the parental cell line. uPAR expression was maintained when resistance was modeled in triple-negative breast cancer by generating doxorubicin and paclitaxel resistant MDA-MB-231 cells (MDA-MB-231 DoxR and MDA-MB-231 TaxR). Using the antagonistic uPAR antibody 2G10, uPAR was imaged in vivo by near-infrared (NIR) optical imaging and (111)In-single photon emission computed tomography (SPECT). Tumor uptake of the (111)In-SPECT probe was high in the three drug-resistant xenografts (> 46 %ID/g) and minimal in uPAR negative xenografts at 72 hours post-injection. This preclinical study demonstrates that uPAR can be targeted for imaging breast cancer models of acquired resistance leading to potential clinical applications. PMID:24505235

  4. Inhibitors of Urokinase Type Plasminogen Activator and Cytostatic Activity from Crude Plants Extracts

    PubMed Central

    Zha, Xueqiang; Diaz, Ricardo; Franco, Jose Javier Rosado; Sanchez, Veronica Forbes; Fasoli, Ezio; Barletta, Gabriel; Carvajal, Augusto; Bansal, Vibha

    2014-01-01

    In view of the clear evidence that urokinase type plasminogen activator (uPA) plays an important role in the processes of tumor cell metastasis, aortic aneurysm, and multiple sclerosis, it has become a target of choice for pharmacological intervention. The goal of this study was thus to determine the presence of inhibitors of uPA in plants known traditionally for their anti-tumor properties. Crude methanol extracts were prepared from the leaves of plants (14) collected from the subtropical dry forest (Guanica, Puerto Rico), and tested for the presence of inhibitors of uPA using the fibrin plate assay. The extracts that tested positive (6) were then partitioned with petroleum ether, chloroform, ethyl acetate and n-butanol, in a sequential manner. The resulting fractions were then tested again using the fibrin plate assay. Extracts from leaves of Croton lucidus (C. lucidus) showed the presence of a strong uPA inhibitory activity. Serial dilutions of these C. lucidus partitions were performed to determine the uPA inhibition IC50 values. The chloroform extract showed the lowest IC50 value (3.52 μg/mL) and hence contained the most potent uPA inhibitor. Further investigations revealed that the crude methanol extract and its chloroform and n-butanol partitions did not significantly inhibit closely related proteases such as the tissue type plasminogen activator (tPA) and plasmin, indicating their selectivity for uPA, and hence superior potential for medicinal use with fewer side effects. In a further evaluation of their therapeutic potential for prevention of cancer metastasis, the C. lucidus extracts displayed cytostatic activity against human pancreatic carcinoma (PaCa-2) cells, as determined through an MTS assay. The cytostatic activities recorded for each of the partitions correlated with their relative uPA inhibitory activities. There are no existing reports of uPA inhibitors being present in any of the plants reported in this study. PMID:23896619

  5. Reduction of mouse atherosclerosis by urokinase inhibition or with a limited-spectrum matrix metalloproteinase inhibitor

    PubMed Central

    Hu, Jie Hong; Touch, Phanith; Zhang, Jingwan; Wei, Hao; Liu, Shihui; Lund, Ida K.; Høyer-Hansen, Gunilla; Dichek, David A.

    2015-01-01

    Aims Elevated activity of urokinase plasminogen activator (uPA) and MMPs in human arteries is associated with accelerated atherosclerosis, aneurysms, and plaque rupture. We used Apoe-null mice with macrophage-specific uPA overexpression (SR-uPA mice; a well-characterized model of protease-accelerated atherosclerosis) to investigate whether systemic inhibition of proteolytic activity of uPA or a subset of MMPs can reduce protease-induced atherosclerosis and aortic dilation. Methods and results SR-uPA mice were fed a high-fat diet for 10 weeks and treated either with an antibody inhibiting mouse uPA (mU1) or a control antibody. mU1-treated mice were also compared with PBS-treated non-uPA-overexpressing Apoe-null mice. Other SR-uPA mice were treated with one of three doses of a limited-spectrum synthetic MMP inhibitor (XL784) or vehicle. mU1 reduced aortic root intimal lesion area (20%; P = 0.05) and aortic root circumference (12%; P = 0.01). All XL784 doses reduced aortic root intimal lesion area (22–29%) and oil-red-O-positive lesion area (36–42%; P < 0.05 for all doses and both end points), with trends towards reduced aortic root circumference (6–10%). Neither mU1 nor XL784 significantly altered percent aortic surface lesion coverage. Several lines of evidence identified MMP-13 as a mediator of uPA-induced aortic MMP activity. Conclusions Pharmacological inhibition of either uPA or selected MMPs decreased atherosclerosis in SR-uPA mice. uPA inhibition decreased aortic dilation. Differential effects of both agents on aortic root vs. distal aortic atherosclerosis suggest prevention of atherosclerosis progression vs. initiation. Systemic inhibition of uPA or a subset of MMPs shows promise for treating atherosclerosis. PMID:25616415

  6. Benefits of maltodextrin intake 2 hours before cholecystectomy by laparotomy in respiratory function and functional capacity: a prospective randomized clinical trial

    PubMed Central

    Zani, Fabiana Vieira Breijão; Aguilar-Nascimento, José Eduardo; Nascimento, Diana Borges Dock; da Silva, Ageo Mário Cândido; Caporossi, Fernanda Stephan; Caporossi, Cervantes

    2015-01-01

    ABSTRACT Objective: To evaluate the change in respiratory function and functional capacity according to the type of preoperative fasting. Methods: Randomized prospective clinical trial, with 92 female patients undergoing cholecystectomy by laparotomy with conventional or 2 hours shortened fasting. The variables measured were the peak expiratory flow, forced expiratory volume in the first second, forced vital capacity, dominant handgrip strength, and non-dominant handgrip strength. Evaluations were performed 2 hours before induction of anesthesia and 24 hours after the operation. Results: The two groups were similar in preoperative evaluations regarding demographic and clinical characteristics, as well as for all variables. However, postoperatively the group with shortened fasting had higher values than the group with conventional fasting for lung function tests peak expiratory flow (128.7±62.5 versus 115.7±59.9; p=0.040), forced expiratory volume in the first second (1.5±0.6 versus 1.2±0.5; p=0.040), forced vital capacity (2.3±1.1 versus 1.8±0.9; p=0.021), and for muscle function tests dominant handgrip strength (24.9±6.8 versus 18.4±7.7; p=0.001) and non-dominant handgrip strength (22.9±6.3 versus 17.0±7.8; p=0.0002). In the intragroup evaluation, there was a decrease in preoperative compared with postoperative values, except for dominant handgrip strength (25.2±6.7 versus 24.9±6.8; p=0.692), in the shortened fasting group. Conclusion: Abbreviation of preoperative fasting time with ingestion of maltodextrin solution is beneficial to pulmonary function and preserves dominant handgrip strength. PMID:26154547

  7. Arctic circulation regimes.

    PubMed

    Proshutinsky, Andrey; Dukhovskoy, Dmitry; Timmermans, Mary-Louise; Krishfield, Richard; Bamber, Jonathan L

    2015-10-13

    Between 1948 and 1996, mean annual environmental parameters in the Arctic experienced a well-pronounced decadal variability with two basic circulation patterns: cyclonic and anticyclonic alternating at 5 to 7 year intervals. During cyclonic regimes, low sea-level atmospheric pressure (SLP) dominated over the Arctic Ocean driving sea ice and the upper ocean counterclockwise; the Arctic atmosphere was relatively warm and humid, and freshwater flux from the Arctic Ocean towards the subarctic seas was intensified. By contrast, during anticylonic circulation regimes, high SLP dominated driving sea ice and the upper ocean clockwise. Meanwhile, the atmosphere was cold and dry and the freshwater flux from the Arctic to the subarctic seas was reduced. Since 1997, however, the Arctic system has been under the influence of an anticyclonic circulation regime (17 years) with a set of environmental parameters that are atypical for this regime. We discuss a hypothesis explaining the causes and mechanisms regulating the intensity and duration of Arctic circulation regimes, and speculate how changes in freshwater fluxes from the Arctic Ocean and Greenland impact environmental conditions and interrupt their decadal variability. PMID:26347536

  8. Arctic circulation regimes

    PubMed Central

    Proshutinsky, Andrey; Dukhovskoy, Dmitry; Timmermans, Mary-Louise; Krishfield, Richard; Bamber, Jonathan L.

    2015-01-01

    Between 1948 and 1996, mean annual environmental parameters in the Arctic experienced a well-pronounced decadal variability with two basic circulation patterns: cyclonic and anticyclonic alternating at 5 to 7 year intervals. During cyclonic regimes, low sea-level atmospheric pressure (SLP) dominated over the Arctic Ocean driving sea ice and the upper ocean counterclockwise; the Arctic atmosphere was relatively warm and humid, and freshwater flux from the Arctic Ocean towards the subarctic seas was intensified. By contrast, during anticylonic circulation regimes, high SLP dominated driving sea ice and the upper ocean clockwise. Meanwhile, the atmosphere was cold and dry and the freshwater flux from the Arctic to the subarctic seas was reduced. Since 1997, however, the Arctic system has been under the influence of an anticyclonic circulation regime (17 years) with a set of environmental parameters that are atypical for this regime. We discuss a hypothesis explaining the causes and mechanisms regulating the intensity and duration of Arctic circulation regimes, and speculate how changes in freshwater fluxes from the Arctic Ocean and Greenland impact environmental conditions and interrupt their decadal variability. PMID:26347536

  9. No consensus on gestational diabetes mellitus screening regimes in Sweden: pregnancy outcomes in relation to different screening regimes 2011 to 2012, a cross-sectional study

    PubMed Central

    2014-01-01

    Background Although associated adverse pregnancy outcomes, no international or Swedish consensus exists that identifies a cut-off value or what screening method to use for definition of gestational diabetes mellitus. This study investigates the following: i) guidelines for screening of GDM; ii) background and risk factors for GDM and selection to OGTT; and iii) pregnancy outcomes in relation to GDM, screening regimes and levels of OGTT 2 hour glucose values. Methods This cross-sectional and population-based study uses data from the Swedish Maternal Health Care Register (MHCR) (2011 and 2012) combined with guidelines for GDM screening (2011–2012) from each Maternal Health Care Area (MHCA) in Sweden. The sample consisted of 184,183 women: 88,140 in 2011 and 96,043 in 2012. Chi-square and two independent samples t-tests were used. Univariate and multivariate logistic regression analyses were performed. Results Four screening regimes of oral glucose tolerance test (OGTT) (75 g of glucose) were used: A) universal screening with a 2-hour cut-off value of 10.0 mmol/L; B) selective screening with a 2-hour cut-off value of 8.9 mmol/L; C) selective screening with a 2-hour cut-off value of 10.0 mmol/L; and D) selective screening with a 2-hour cut-off value of 12.2 mmol/L. The highest prevalence of GDM (2.9%) was found with a 2-hour cut-off value of 8.9 mmol/L when selective screening was applied. Unemployment and low educational level were associated with an increased risk of GDM. The OR was 4.14 (CI 95%: 3.81-4.50) for GDM in obese women compared to women with BMI <30 kg/m2. Women with non-Nordic origin presented a more than doubled risk for GDM compared to women with Nordic origin (OR = 2.24; CI 95%: 2.06-2.43). Increasing OGTT values were associated with increasing risks of adverse pregnancy outcomes. Conclusions There was no consensus regarding screening regimes for GDM from 2011 through 2012 when four different regimes were applied in Sweden. Increasing

  10. The tyrosine phosphatase SHP-2 controls urokinase-dependent signaling and functions in human vascular smooth muscle cells

    SciTech Connect

    Kiyan, Julia Haller, Hermann; Dumler, Inna

    2009-04-01

    The urokinase (uPA)/urokinase receptor (uPAR) multifunctional system is an important mediator of functional behaviour of human vascular smooth muscle cells (VSMC). uPAR associates with platelet-derived growth factor receptor {beta} (PDGFR-{beta}), which serves as a transmembrane adaptor for uPAR in VSMC, to transduce intracellular signaling and initiate functional changes. The precise and rapid propagation of these signaling cascades demands both strict and flexible regulatory mechanisms that remain unexplored. We provide evidence that the tyrosine phosphatase SHP-2 mediates these processes. uPA regulated SHP-2 phosphorylation, catalytic activity, and its co-localization and association with the PDGFR-{beta}. Active PDGFR-{beta} was required for the uPA-induced SHP-2 phosphorylation. uPAR-directed STAT1 pathway was disturbed in cells expressing SHP-2 inactive mutant. Both, cell proliferation and migration were impaired in VSMC with downregulated SHP-2. Elucidating the underlying mechanisms, we found that uPA induced SHP-2 recruitment to lipid rafts. Disruption of rafts abolished uPA-related control of SHP-2 phosphorylation, its association with PDGFR-{beta} and finally the VSMC functional responses. Our results demonstrate that SHP-2 plays an important role in uPA-directed signaling and functional control of human VSMC and suggest that this phosphatase might contribute to the pathogenesis of the uPA-related vascular remodeling.

  11. Design, Synthesis, Biochemical Studies, Cellular Characterization, and Structure-Based Computational Studies of Small Molecules Targeting the Urokinase Receptor

    PubMed Central

    Wang, Fang; Knabe, W. Eric; Li, Liwei; Jo, Inha; Mani, Timmy; Roehm, Hartmut; Oh, Kyungsoo; Li, Jing; Khanna, May; Meroueh, Samy O.

    2012-01-01

    The urokinase receptor (uPAR) serves as a docking site to the serine protease urokinase-type plasminogen activator (uPA) to promote extracellular matrix (ECM) degradation and tumor invasion and metastasis. Previously, we had reported a small molecule inhibitor of the uPAR•uPA interaction that emerged from structure-based virtual screening. Here, we measure the affinity of a large number of derivatives from commercial sources. Synthesis of additional compounds was carried out to probe the role of various groups on the parent compound. Extensive structure-based computational studies suggested a binding mode for these compounds that led to a structure-activity relationship study. Cellular studies in non-small cell lung cancer (NSCLC) cell lines that include A549, H460 and H1299 showed that compounds blocked invasion, migration and adhesion. The effects on invasion of active compounds were consistent with their inhibition of uPA and MMP proteolytic activity. These compounds showed weak cytotoxicity consistent with the confined role of uPAR to metastasis. PMID:22771232

  12. Relationship between urokinase plasminogen activator receptor (uPAR) and the invasion of human prenatal hair follicle.

    PubMed

    Gao, Qiangguo; Fu, Gang; Huang, Gang; Lian, Xiaohua; Yu, Jin; Yang, Tian

    2010-08-01

    During the morphogenesis of hair follicles, the invasive migration of basal keratinocytes resembles cell's dissemination of tissue remodeling. The urokinase-type plasminogen activator receptor (uPAR) appears to be a key molecule in the metastasis. In order to elucidate the relationship between uPAR and the invasion of the human hair follicle, immunohistochemistry, RT-PCR, plasmids transfection, and western blot were used. The results showed that uPAR was expressed in the outermost epithelial cells of the hair follicle and the basal keratinocytes of epidermis, and that the expression decreased with the development of the hair follicle. The cells of the outer root sheath (ORS) and interfollicle epidermis, which overexpressed uPAR, acquired increased invasiveness; however, they showed decreased invasion with overexpression of the urokinase-type plasminogen activator amino terminal fragment (uPA ATF), which inhibited the combination of uPAR and uPA competitively, and the cell invasive migration with overexpressed uPAR was required activated extracellular signal-regulated kinases (ERK). These results implied that overexpression of uPAR promote the invasive migration of hair follicle into the dermis in uPA-dependent and independent manner during human prenatal development. PMID:20012874

  13. Altered expression of urokinase-type plasminogen activator and plasminogen activator inhibitor in high-risk soft tissue sarcomas.

    PubMed

    Benassi, M S; Ponticelli, F; Azzoni, E; Gamberi, G; Pazzaglia, L; Chiechi, A; Conti, A; Spessotto, P; Scapolan, M; Pignotti, E; Bacchini, P; Picci, P

    2007-09-01

    In recent years, classification of soft-tissue sarcomas (STS) has improved with cytogenetic analyses, but their clinical behavior is still not easily predictable. The aim of this study was to detect alterations in the urokinase-type plasminogen system, involved in tumor growth and invasion, by comparing mRNA levels of its components with those of paired normal tissues, and relating them with patient clinical course. Real-time PCR was performed on human STS cell lines and tissues from highly malignant STS, including leiomyosarcomas and malignant fibrous histiocytomas, to evaluate the expression of urokinase-type plasminogen activator (uPA), uPA receptor (uPAR) and plasminogen activator inhibitor-1 (PAI-1). Immunohistochemistry of gene products was also performed. Median mRNA values of all genes studied were higher in tumors than in paired normal tissues. In agreement with data on STS cell lines, significant up-regulation for uPA and PAI-1 genes compared to reference values was seen. Moreover, different levels of expression were related to histotype and metastatic phenotype. There was accordance between uPA mRNA and protein expression, while immunodetection of PAI-1 product was weak and scattered. Clearly, the controversial role of PAI-1 protein requires further biological analyses, but evident involvement of uPA/PAI-1 gene overexpression in STS malignancy may highlight a molecular defect useful in discriminating STS high-risk patients. PMID:17523079

  14. Urokinase receptor-dependent and -independent p56/59(hck) activation state is a molecular switch between myelomonocytic cell motility and adherence.

    PubMed Central

    Chiaradonna, F; Fontana, L; Iavarone, C; Carriero, M V; Scholz, G; Barone, M V; Stoppelli, M P

    1999-01-01

    Anchorage-independent myelomonocytic cells acquire adherence within minutes of differentiation stimuli, such as the proteolytically inactive N-terminal fragment of urokinase binding to its cognate glycosylphosphatidylinositol (GPI)-anchored receptor. Here, we report that urokinase-treated differentiating U937 monocyte-like cells exhibit a rapid and transient inhibition of p56/59(hck) and p55(fgr) whereas no changes in the activity of other Src family kinases, such as p53/56(lyn) and p59(fyn) were observed. U937 transfectants expressing a kinase-defective (Lys267 to Met) p56/59(hck) variant exhibit enhanced adhesiveness and a marked F-actin redistribution in thin protruding structures. Conversely, urokinase as well as expression of wild-type or constitutively active (Tyr499 to Phe) p56/59(hck) stimulates the directional migration of uninduced U937 cells. Accordingly, expression of constitutively active or kinase inactive p56/59(hck) selectively prevents urokinase receptor-dependent induction of either adhesion or motility, indicating that a specific activation state of p56/59(hck) is required for each cell response. In conclusion, modulation of the intracellular p56/59(hck) tyrosine kinase activity switches cell motility towards adherence, providing a mutually exclusive mechanism to regulate these properties during monocyte/macrophage differentiation in vivo. PMID:10357814

  15. Regimes of Helium Burning

    SciTech Connect

    Timmes, F. X.; Niemeyer, J. C.

    2000-07-10

    The burning regimes encountered by laminar deflagrations and Zeldovich von Neumann Doering [ZND] detonations propagating through helium-rich compositions in the presence of buoyancy-driven turbulence are analyzed. Particular attention is given to models of X-ray bursts that start with a thermonuclear runaway on the surface of a neutron star and to the thin-shell helium instability of intermediate-mass stars. In the X-ray burst case, turbulent deflagrations propagating in the lateral or radial direction encounter a transition from the distributed regime to the flamelet regime at a density of {approx}108 g cm-3. In the radial direction, the purely laminar deflagration width is larger than the pressure scale height for densities smaller than {approx}106 g cm-3. Self-sustained laminar deflagrations traveling in the radial direction cannot exist below this density. Similarly, the planar ZND detonation width becomes larger than the pressure scale height at {approx}107 g cm-3, suggesting that steady state, self-sustained detonations cannot come into existence in the radial direction. In the thin helium shell case, turbulent deflagrations traveling in the lateral or radial direction encounter the distributed regime at densities below {approx}107 g cm-3 and the flamelet regime at larger densities. In the radial direction, the purely laminar deflagration width is larger than the pressure scale height for densities smaller than {approx}104 g cm-3, indicating that steady state laminar deflagrations cannot form below this density. The planar ZND detonation width becomes larger than the pressure scale height at {approx}5x10{sup 4} g cm-3, suggesting that steady state, self-sustained detonations cannot come into existence in the radial direction. (c) 2000 The American Astronomical Society.

  16. Urine soluble urokinase-type plasminogen activator receptor levels correlate with proteinuria in Puumala hantavirus infection

    PubMed Central

    Outinen, Tuula K.; Mäkelä, Satu; Huttunen, Reetta; Mäenpää, Niina; Libraty, Daniel; Vaheri, Antti; Mustonen, Jukka; Aittoniemi, Janne

    2014-01-01

    Objectives Urokinase-type plasminogen activator receptor (uPAR) is upregulated during inflammation and known to bind to β3-integrins, receptors used by pathogenic hantaviruses to enter endothelial cells. It has been proposed that soluble uPAR (suPAR) is a circulating factor that causes focal segmental glomerulosclerosis and proteinuria by activating β3-integrin in kidney podocytes. Proteinuria is also a characteristic feature of hantavirus infections. The aim of this study was to evaluate the relation between urine suPAR levels and disease severity in acute Puumala hantavirus (PUUV) infection. Design A single-centre, prospective cohort study. Subjects and methods Urinary suPAR levels were measured twice during the acute phase and once during convalescence in 36 patients with serologically confirmed PUUV infection. Fractional excretion of suPAR (FE suPAR) and of albumin (FE alb) were calculated. Results The FE suPAR was significantly elevated during the acute phase of PUUV infection compared to the convalescent phase (median 3.2%, range 0.8–52.0%, vs. median 1.9%, range 1.0–5.8%, P = 0.005). Maximum FE suPAR was correlated markedly with maximum FE alb (r = 0.812, P < 0.001), and with several other variables that reflect disease severity. There was a positive correlation with the length of hospitalization (r = 0.455, P = 0.009) and maximum plasma creatinine level (r = 0.780, P < 0.001), and an inverse correlation with minimum urinary output (r = −0.411, P = 0.030). There was no correlation between FE suPAR and plasma suPAR (r = 0.180, P = 0.324). Conclusion Urinary suPAR is markedly increased during acute PUUV infection and is correlated with proteinuria. High urine suPAR level may reflect local production of suPAR in the kidney during the acute infection. PMID:24717117

  17. Characterization of the murine plasminogen/urokinase-type plasminogen-activator system.

    PubMed

    Lijnen, H R; Van Hoef, B; Collen, D

    1996-11-01

    The murine plasminogen/urokinase-type plasminogen-activator (u-PA) system was studied using purified proteins, plasma and endothelioma cells. Recombinant murine u-PA was obtained as a single-chain molecule of 45 kDa which was converted to two-chain u-PA with plasmin by cleavage of the Lys159-Ile160 peptide bond. Murine plasminogen, purified from plasma as a single-chain protein of 95 kDa, was resistant to quantitative activation with murine recombinant two-chain u-PA: only 15% activation within 1 h at 37 degrees C was obtained in mixtures of 1 microM plasminogen and 5 nM recombinant two-chain u-PA, whereas quantitative activation was observed in the autologous human system. Addition of 6-aminohexanoic acid to native murine plasminogen resulted in quantitative activation within 1 h. In murine plasma in vitro, plasminogen was also resistant to quantitative activation with u-PA (50% activation within 1 h at 37 degrees C with 50 nM recombinant two-chain u-PA, whereas in the human system nearly quantitative activation was obtained). Murine plasma clots submerged in murine plasma were resistant to lysis with u-PA; < or = 2% clot lysis in 2 h was obtained with 80 nM recombinant two-chain u-PA in the autologous murine system whereas 50% clot lysis in 2 h required only 15 nM recombinant two-chain u-PA in the autologous human system. Saturable binding of murine recombinant two-chain u-PA was observed to murine endothelioma cells that are genetically deficient in u-PA (u-PA-/- End cells). Binding was characterized by a Kd of 5.5 nM and 800000 binding sites/cell. However, u-PA-/- End cells did not significantly stimulate the activation rate of murine plasminogen by murine recombinant two-chain u-PA and did not enhance the plasmin-mediated conversion rate of murine recombinant single-chain u-PA to its two-chain derivative. Murine recombinant two-chain u-PA bound to murine endothelioma cells was quantitatively inhibited by murine plasminogen-activator inhibitor-1 (PAI-1). Thus

  18. High level of urokinase plasminogen activator contributes to cholangiocarcinoma invasion and metastasis

    PubMed Central

    Thummarati, Parichut; Wijitburaphat, Sitsom; Prasopthum, Aruna; Menakongka, Apaporn; Sripa, Banchob; Tohtong, Rutaiwan; Suthiphongchai, Tuangporn

    2012-01-01

    AIM: To investigate the role of urokinase plasminogen activator (uPA) in cholangiocarcinoma (CCA) invasion and its correlation with clinicopathological parameters. METHODS: uPA expression in CCA tissue was determined by immunohistochemistry. The level of uPA from two CCA cell lines (HuCCA-1 and KKU-M213) and a non-cancer immortalized cholangiocyte cell line (H69) was monitored by plasminogen-gelatin zymography and western blotting, whereas that of plasminogen activator inhibitor type 1 (PAI-1) protein and uPA receptor (uPAR) mRNA was monitored by western blotting and quantitative real-time reverse transcriptase polymerase chain reaction, respectively. Two independent methods were employed to suppress uPA function: a synthetic uPA inhibitor (B428) and silencing of uPA gene expression using siRNA. In vitro invasion of the uPA-disrupted cells was assessed by Matrigel-coated Transwell assay. RESULTS: The immunohistochemical study showed that 75.3% (131/174) of CCA tissues expressed uPA. High uPA expression was correlated with lymphatic invasion and metastasis of CCA patients. Plasminogen-gelatin zymography of the conditioned media and cell-surface eluates showed that both CCA cell lines, but not H69, expressed both secreted and membrane-bound forms of uPA. Although the two CCA cell lines, HuCCA-1 and KKU-M213, expressed a relatively high level of uPA and uPAR, the latter exhibited a much lower degree of in vitro invasiveness, correlating with a high expression of PAI-1 in the latter, but not in the former. Suppressing uPA function with a specific uPA inhibitor, B428, or with siRNA against uPA reduced in vitro invasiveness of KKU-M213 cells, demonstrating the requirement for uPA in the invasiveness of CCA cells. Therefore, our in vivo and in vitro studies suggest that uPA is an important requirement for the invasion process of CCA. CONCLUSION: uPA expression correlates with lymphatic invasion and metastasis in vivo and is required for CCA cell invasion in vitro

  19. Radiation-induced hypomethylation triggers urokinase plasminogen activator transcription in meningioma cells.

    PubMed

    Velpula, Kiran Kumar; Gogineni, Venkateswara Rao; Nalla, Arun Kumar; Dinh, Dzung H; Rao, Jasti S

    2013-02-01

    Our previous studies have shown the role of radiation-induced urokinase plasminogen activator (uPA) expression in the progression of meningioma. In the present study, we investigated whether modulation of DNA methylation profiles could regulate uPA expression. Initially, radiation treatment was found to induce hypomethylation in meningioma cells with a decrease in DNA (cytosine-5)-methyltransferase 1 (DNMT1) and methyl-CpG binding domain protein (MBD) expression. However, oxidative damage by H(2)O(2) or pretreatment of irradiated cells with N-acetyl cysteine (NAC) did not show any influence on these proteins, thereby indicating a radiation-specific change in the methylation patterns among meningioma cells. Further, we identified that hypomethylation is coupled to an increase in uPA expression in these cells. Azacytidine treatment induced a dose-dependent surge of uPA expression, whereas pre-treatment with sodium butyrate inhibited radiation-induced uPA expression, which complemented our prior results. Methylation-specific polymerase chain reaction on bisulfite-treated genomic DNA revealed a diminished methylation of uPA promoter in irradiated cells. Transfection with small hairpin RNA (shRNA)-expressing plasmids targeting CpG islands of the uPA promoter showed a marked decline in uPA expression with subsequent decrease in invasion and proliferation of meningioma cells. Further, radiation treatment was found to recruit SP1 transcription factor, which was abrogated by shRNA treatment. Analysis on signaling events demonstrated the activation of MAP kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) in radiation-treated cells, while U0126 (MEK/ERK inhibitor) blocked hypomethylation, recruitment of SP1, and uPA expression. In agreement with our in vitro data, low DNMT1 levels and high uPA were found in intracranial tumors treated with radiation compared to untreated tumors. In conclusion, our data suggest that radiation-mediated hypomethylation triggers u

  20. Radiation-Induced Hypomethylation Triggers Urokinase Plasminogen Activator Transcription in Meningioma Cells1

    PubMed Central

    Velpula, Kiran Kumar; Gogineni, Venkateswara Rao; Nalla, Arun Kumar; Dinh, Dzung H; Rao, Jasti S

    2013-01-01

    Our previous studies have shown the role of radiation-induced urokinase plasminogen activator (uPA) expression in the progression of meningioma. In the present study, we investigated whether modulation of DNA methylation profiles could regulate uPA expression. Initially, radiation treatment was found to induce hypomethylation in meningioma cells with a decrease in DNA (cytosine-5)-methyltransferase 1 (DNMT1) and methyl-CpG binding domain protein (MBD) expression. However, oxidative damage by H2O2 or pretreatment of irradiated cells with N-acetyl cysteine (NAC) did not show any influence on these proteins, thereby indicating a radiation-specific change in the methylation patterns among meningioma cells. Further, we identified that hypomethylation is coupled to an increase in uPA expression in these cells. Azacytidine treatment induced a dose-dependent surge of uPA expression, whereas pre-treatment with sodium butyrate inhibited radiation-induced uPA expression, which complemented our prior results. Methylation-specific polymerase chain reaction on bisulfite-treated genomic DNA revealed a diminished methylation of uPA promoter in irradiated cells. Transfection with small hairpin RNA (shRNA)-expressing plasmids targeting CpG islands of the uPA promoter showed a marked decline in uPA expression with subsequent decrease in invasion and proliferation of meningioma cells. Further, radiation treatment was found to recruit SP1 transcription factor, which was abrogated by shRNA treatment. Analysis on signaling events demonstrated the activation of MAP kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) in radiation-treated cells, while U0126 (MEK/ERK inhibitor) blocked hypomethylation, recruitment of SP1, and uPA expression. In agreement with our in vitro data, low DNMT1 levels and high uPA were found in intracranial tumors treated with radiation compared to untreated tumors. In conclusion, our data suggest that radiation-mediated hypomethylation triggers u

  1. The "lipid accumulation product" is associated with 2-hour postload glucose outcomes in overweight/obese subjects with nondiabetic fasting glucose.

    PubMed

    Malavazos, Alexis Elias; Cereda, Emanuele; Ermetici, Federica; Caccialanza, Riccardo; Briganti, Silvia; Rondanelli, Mariangela; Morricone, Lelio

    2015-01-01

    "Lipid accumulation product" (LAP) is a continuous variable based on waist circumference and triglyceride concentration previously associated with insulin resistance. We investigated the accuracy of LAP in identifying oral glucose tolerance test (OGTT) abnormalities and compared it to the homeostasis model assessment of insulin resistance (HOMA-IR) in a population of overweight/obese outpatients presenting with nondiabetic fasting glucose. We studied 381 (male: 23%) adult (age: 18-70 years) overweight/obese Caucasians (body mass index: 36.9 ± 5.4 Kg/m(2)) having fasting plasma glucose < 7.0 mmol/L. OGTT was used to diagnose unknown glucose tolerance abnormalities: impaired glucose tolerance (IGT) and type-2 diabetes mellitus (T2-DM). According to OGTT 92, subjects had an IGT and 33 were diagnosed T2-DM. Logistic regression analysis detected a significant association for both LAP and HOMA-IR with single (IGT and T2-DM) and composite (IGT + T2-DM) abnormal glucose tolerance conditions. However, while the association with diabetes was similar between LAP and HOMA-IR, the relationship with IGT and composite outcomes by models including LAP was significantly superior to those including HOMA-IR (P = 0.006 and P = 0.007, resp.). LAP seems to be an accurate index, performing better than HOMA-IR, for identifying 2-hour postload OGTT outcomes in overweight/obese patients with nondiabetic fasting glucose. PMID:25792981

  2. The “Lipid Accumulation Product” Is Associated with 2-Hour Postload Glucose Outcomes in Overweight/Obese Subjects with Nondiabetic Fasting Glucose

    PubMed Central

    Malavazos, Alexis Elias; Cereda, Emanuele; Ermetici, Federica; Caccialanza, Riccardo; Briganti, Silvia; Rondanelli, Mariangela; Morricone, Lelio

    2015-01-01

    “Lipid accumulation product” (LAP) is a continuous variable based on waist circumference and triglyceride concentration previously associated with insulin resistance. We investigated the accuracy of LAP in identifying oral glucose tolerance test (OGTT) abnormalities and compared it to the homeostasis model assessment of insulin resistance (HOMA-IR) in a population of overweight/obese outpatients presenting with nondiabetic fasting glucose. We studied 381 (male: 23%) adult (age: 18–70 years) overweight/obese Caucasians (body mass index: 36.9 ± 5.4 Kg/m2) having fasting plasma glucose < 7.0 mmol/L. OGTT was used to diagnose unknown glucose tolerance abnormalities: impaired glucose tolerance (IGT) and type-2 diabetes mellitus (T2-DM). According to OGTT 92, subjects had an IGT and 33 were diagnosed T2-DM. Logistic regression analysis detected a significant association for both LAP and HOMA-IR with single (IGT and T2-DM) and composite (IGT + T2-DM) abnormal glucose tolerance conditions. However, while the association with diabetes was similar between LAP and HOMA-IR, the relationship with IGT and composite outcomes by models including LAP was significantly superior to those including HOMA-IR (P = 0.006 and P = 0.007, resp.). LAP seems to be an accurate index, performing better than HOMA-IR, for identifying 2-hour postload OGTT outcomes in overweight/obese patients with nondiabetic fasting glucose. PMID:25792981

  3. Dynamic Treatment Regimes

    PubMed Central

    Chakraborty, Bibhas; Murphy, Susan A.

    2014-01-01

    A dynamic treatment regime consists of a sequence of decision rules, one per stage of intervention, that dictate how to individualize treatments to patients based on evolving treatment and covariate history. These regimes are particularly useful for managing chronic disorders, and fit well into the larger paradigm of personalized medicine. They provide one way to operationalize a clinical decision support system. Statistics plays a key role in the construction of evidence-based dynamic treatment regimes – informing best study design as well as efficient estimation and valid inference. Due to the many novel methodological challenges it offers, this area has been growing in popularity among statisticians in recent years. In this article, we review the key developments in this exciting field of research. In particular, we discuss the sequential multiple assignment randomized trial designs, estimation techniques like Q-learning and marginal structural models, and several inference techniques designed to address the associated non-standard asymptotics. We reference software, whenever available. We also outline some important future directions. PMID:25401119

  4. Defect of vacuolar protein sorting stimulates proteolytic processing of human urokinase-type plasminogen activator in the yeast Hansenula polymorpha.

    PubMed

    Agaphonov, Michael; Romanova, Nina; Sokolov, Sviatoslav; Iline, Anna; Kalebina, Tatyana; Gellissen, Gerd; Ter-Avanesyan, Michael

    2005-11-01

    Human urokinase-type plasminogen activator (uPA) is poorly secreted by yeast cells. Here, we have selected Hansenula polymorpha mutants with increased productivity of active extracellular uPA. Several of the obtained mutants also demonstrated a defect of sorting of carboxypeptidase Y to the vacuole and the mutant loci have been identified in six of them. All these mutations damaged genes involved in protein traffic between the Golgi apparatus and the vacuole, namely PEP3, VPS8, VPS10, VPS17, and VPS35. We have shown that inactivation of the VPS10 gene encoding the vacuolar protein sorting receptor does not increase uPA secretion but stimulates its proteolytic processing. PMID:16181812

  5. Re-engineering the Immune Response to Metastatic Cancer: Antibody-Recruiting Small Molecules Targeting the Urokinase Receptor.

    PubMed

    Rullo, Anthony F; Fitzgerald, Kelly J; Muthusamy, Viswanathan; Liu, Min; Yuan, Cai; Huang, Mingdong; Kim, Minsup; Cho, Art E; Spiegel, David A

    2016-03-01

    Developing selective strategies to treat metastatic cancers remains a significant challenge. Herein, we report the first antibody-recruiting small molecule (ARM) that is capable of recognizing the urokinase-type plasminogen activator receptor (uPAR), a uniquely overexpressed cancer cell-surface marker, and facilitating the immune-mediated destruction of cancer cells. A co-crystal structure of the ARM-U2/uPAR complex was obtained, representing the first crystal structure of uPAR complexed with a non-peptide ligand. Finally, we demonstrated that ARM-U2 substantially suppresses tumor growth in vivo with no evidence of weight loss, unlike the standard-of-care agent doxorubicin. This work underscores the promise of antibody-recruiting molecules as immunotherapeutics for treating cancer. PMID:26879524

  6. QSAR study of substituted 2-pyridinyl guanidines as selective urokinase-type plasminogen activator (uPA) inhibitors.

    PubMed

    Karthikeyan, C; Moorthy, N S Hari Narayana; Trivedi, Piyush

    2009-02-01

    A quantitative structure-activity relationship analysis was conducted on two different series of pyridinylguanidines acting as inhibitors of urokinase-type plasminogen activator using QuaSAR descriptors of molecular modeling software MOE. Multiple linear regression analysis following a stepwise scheme was employed to generate QSARs that relate molecular descriptors to uPA inhibitory activity data of the title compounds. Among the several QSARs generated by MLR analysis, the best models were selected on the basis of their statistical significance and predictive potential. The interpretation of the selected QSAR models suggest that uPA inhibitory activity of compounds in series 1 is influenced by their molecular shape, molecular flexibility and halogen atoms in the molecule whereas the uPA inhibitory potency of compounds in series 2 is dependent on molecular lipophilicity, number of double bonds and spatial orientation of bulky substituents in the molecule. PMID:19012070

  7. Relationship of Exercise, Age, and Gender on Decompression Sickness and Venous Gas Emboli During 2-Hour Oxygen Prebreathe Prior to Hypobaric Exposure

    NASA Technical Reports Server (NTRS)

    Conkin, J.; Gernhardt, M. L.; Foster, P. P.; Pilmanis, A. A.; Butler, B. D.; Beltran, E.; Fife, C. E.; Vann, R. D.; Gerth, W. A.; Loftin, K. C.; Paloski, William H. (Technical Monitor)

    2000-01-01

    We evaluated four 2-hour oxygen prebreathe protocols combining adynamia (non-walking) and 4 different amounts of exercise for potential use with extravehicular activity (EVA) on the International Space Station. Phase I: upper and lower body exercises using dual-cycle ergometry (75% VO2 max for 10 min). Phase 11: same ergometry plus 24 min of light exercise that simulated space suit preparations. Phase III: same 24 min of light exercise but no ergometry, and Phase IV: 56 min of light exercise without ergometry. After 80 min on 100% O2, the subjects breathed 26.5% O2 - 73.5% N2 for 30 min at 10.2 psi. All subjects performed a series of upper body exercises from a recumbent position for 4 hrs at 4.3 psi to simulate EVA work. Venous gas emboli (VGE) were monitored every 12 min using precordial Doppler ultrasound. The 39 female and 126 male exposures were analyzed for correlations between decompression sickness (DCS) or VGE, and risk variables. The duration and quantity of exercise during prebreathe inversely relates to DCS and VGE incidence. The type and distribution of the 19 cases of DCS were similar to historical cases. There was no correlation of age, gender, body mass index, or fitness level with greater incidence of DCS or all VGE. However there were more Grade IV VGE in males > 40 years (10 of 19) than in those =< 40 years (3 of 107), with p<0.01 from Fisher's Exact Chi square The latency time for VGE was longer (103 min +/- 56 SD, n = 15 versus 53 min +/- 31, n =13) when the ergometry occurred about 15 min into the prebreathe than when performed at the start of the prebreathe, but the order of the ergometry did not influence the overall DCS and VGE incidence. An increasing amount of exercise during prebreathes reduced the risk of DCS during subsequent exposures to 4.3 psi. Age, gender, or fitness level did not correlate with the incidence of DCS or VGE (combination of Grades I-IV). However males greater than 40 years had a higher incidence of Grade IV VGE.

  8. Transradial Approach for Transcatheter Selective Superior Mesenteric Artery Urokinase Infusion Therapy in Patients with Acute Extensive Portal and Superior Mesenteric Vein Thrombosis

    SciTech Connect

    Wang Maoqiang Guo Liping; Lin Hanying; Liu Fengyong; Duan Feng; Wang Zhijun

    2010-02-15

    The purpose of this investigation was to assess the feasibility and effectiveness of transradial approach for transcatheter superior mesenteric artery (SMA) urokinase infusion therapy in patients with acute extensive portal and superior mesenteric venous thrombosis. During a period of 7 years, 16 patients with acute extensive thrombosis of the portal (PV) and superior mesenteric veins (SMV) were treated by transcatheter selective SMA urokinase infusion therapy by way of the radial artery. The mean age of the patients was 39.5 years. Through the radial sheath, a 5F Cobra catheter was inserted into the SMA, and continuous infusion of urokinase was performed for 5-11 days (7.1 {+-} 2.5 days). Adequate anticoagulation was given during treatment, throughout hospitalization, and after discharge. Technical success was achieved in all 16 patients. Substantial clinical improvement was seen in these 16 patients after the procedure. Minor complications at the radial puncture site were observed in 5 patients, but trans-SMA infusion therapy was not interrupted. Follow-up computed tomography scan before discharge demonstrated nearly complete disappearance of PV-SMV thrombosis in 9 patients and partial recanalization of PV-SMV thrombosis in 7 patients. The 16 patients were discharged 9-19 days (12 {+-} 6.0 days) after admission. Mean duration of follow-up after hospital discharge was 44 {+-} 18.5 months, and no recurrent episodes of PV-SMV thrombosis developed during that time period. Transradial approach for transcatheter selective SMA urokinase infusion therapy in addition to anticoagulation is a safe and effective therapy for the management of patients with acute extensive PV-SMV thrombosis.

  9. The human urokinase-plasminogen activator gene (PLAU) is located on chromosome 10q24 centromeric to the HOX11 gene

    SciTech Connect

    Stein, P.M.; Stass, S.A.; Kagan, J. )

    1993-04-01

    Urokinase-plasminogen activator is one of two soluble serine proteases that are produced by humans and that convert plasminogen, an inactive proenzyme present in plasma and other extracellular fluids, to plasmin, a protease with broad substrate specificities. Its activity is involved in processes requiring localized extracellular proteolysis such as fibrinolysis, tissue remodeling, and cell migration. Increased production of urokinase has been associated with cancer metastases. The gene for urokinase-plasminogen activator, PLAU, was mapped to chromosome 10q24-qter. By employing somatic cell genetics, polymerase chain reaction (PCR), and Southern blot analysis, the authors assign PLAU to chromosome 10q24. Human chromosome segment 10q23-q25 contains the genes for terminal deoxynucleotidyltransferase, cytochrome P450IIC, glutamic-oxaloacetic transaminase, and plasma retinol binding protein, which form a syntenic group on murine chromosome 19. It is therfore of interest that PLAU and glutamate dehydrogenase, which are on murine chromosome 14, also map in or close to this region of human chromosome 10.

  10. ApaL1 urokinase and Taq1 vitamin D receptor gene polymorphisms in first-stone formers, recurrent stone formers, and controls in a Caucasian population.

    PubMed

    Aykan, Serdar; Tuken, Murat; Gunes, Sezgin; Akin, Yigit; Ozturk, Murat; Seyhan, Serkan; Yuruk, Emrah; Temiz, Mustafa Zafer; Yılmaz, Ali Faik; Nguyen, Daniel P

    2016-04-01

    The purpose of this study was to determine differences in genotype distribution and allele frequency of urokinase and vitamin D receptor (VDR) single nucleotide polymorphisms (SNPs) between first-stone formers, recurrent stone formers, and controls in a Caucasian population. A total of 86 first-stone formers, 78 recurrent stone formers, and 167 controls were included. Urokinase and VDR SNPs were tested by gene amplification followed by ApaL1 and Taq1 endonuclease digestion, respectively. Baseline variables, genotype, and allele frequencies were compared between the three groups, using descriptive statistics. Adjusted odds ratios were calculated to estimate the risk for recurrent urolithiasis associated with genotypes. We found that differences in the distribution of ApaL1 SNP and Taq1 SNP genotypes were statistically different between recurrent stone formers and first-stone formers, and between recurrent stone formers and controls. Allele frequency analysis showed that the T allele for ApaL1 SNP and the C allele for Taq1 SNP were significantly associated with recurrent urolithiasis. For Taq1 SNP, logistic regression analysis showed that the C/C genotype was associated with a more than threefold higher risk for recurrent urolithiasis. We conclude that ApaL1 and Taq1 SNPs of the urokinase and VDR genes are associated with recurrent urolithiasis in a Caucasian population. PMID:26275878

  11. Examination Regimes and Student Achievement

    ERIC Educational Resources Information Center

    Cosentino de Cohen, Clemencia

    2010-01-01

    Examination regimes at the end of secondary school vary greatly intra- and cross-nationally, and in recent years have undergone important reforms often geared towards increasing student achievement. This research presents a comparative analysis of the relationship between examination regimes and student achievement in the OECD. Using a micro…

  12. Mutation of the protein-O-mannosyltransferase enhances secretion of the human urokinase-type plasminogen activator in Hansenula polymorpha.

    PubMed

    Agaphonov, Michael O; Sokolov, Sviatoslav S; Romanova, Nina V; Sohn, Jung-Hoon; Kim, So-Young; Kalebina, Tatyana S; Choi, Eui-Sung; Ter-Avanesyan, Michael D

    2005-10-15

    Human urokinase-type plasminogen activator (uPA) is poorly secreted and aggregates in the endoplasmic reticulum of yeast cells due to inefficient folding. A screen for Hansenula polymorpha mutants with improved uPA secretion revealed a gene encoding a homologue of the Saccharomyces cerevisiae protein-O-mannosyltransferase Pmt1p. Expression of the H. polymorpha PMT1 gene (HpPMT1) abolished temperature sensitivity of the S. cerevisiae pmt1 pmt2 double mutant. As in S. cerevisiae, inactivation of the HpPMT1 gene affected electrophoretic mobility of the O-glycosylated protein, extracellular chitinase. In contrast to S. cerevisiae, disruption of HpPMT1 alone caused temperature sensitivity. Inactivation of the HpPMT1 gene decreased intracellular aggregation of uPA, suggesting that enhanced secretion of uPA was due to improvement of its folding in the endoplasmic reticulum. Unlike most of the endoplasmic reticulum membrane proteins, HpPmt1p possesses the C-terminal KDEL retention signal. PMID:16200504

  13. Risk factors associated with serum levels of the inflammatory biomarker soluble urokinase plasminogen activator receptor in a general population.

    PubMed

    Haupt, Thomas H; Kallemose, Thomas; Ladelund, Steen; Rasmussen, Line Jh; Thorball, Christian W; Andersen, Ove; Pisinger, Charlotta; Eugen-Olsen, Jesper

    2014-01-01

    The soluble urokinase plasminogen activator receptor (suPAR) is a biomarker of mortality risk in various patient populations. However, little is known about the implications of lifestyle for suPAR levels in the general population. Lifestyle, demographic, and cardiovascular disease (CVD) risk factor data were collected from 5,538 participants in the Danish population-based Inter99 study. Their suPAR levels were measured using a sandwich enzyme-linked immunosorbent assay. In the final adjusted model, smoking and morbid obesity were strongly associated with higher suPAR levels (P < 0.001). An unhealthy diet and alcohol abstinence in men were also associated with higher suPAR levels. Physical activity in leisure time had a modest impact on suPAR levels in univariate analysis, but not in the final adjusted model. In conclusion, smoking and morbid obesity were strongly associated with higher serum suPAR levels in this general population. Diet and alcohol consumption also seemed to impact suPAR levels. Lifestyle changes are likely to affect suPAR since ex-smokers had suPAR levels comparable to those of never-smokers. PMID:25574132

  14. Increased Soluble Urokinase-Type Plasminogen Activator Receptor (suPAR) Levels in Plasma of Suicide Attempters

    PubMed Central

    Ventorp, Filip; Gustafsson, Anna; Träskman-Bendz, Lil; Westrin, Åsa; Ljunggren, Lennart

    2015-01-01

    The soluble form of the urokinase receptor, suPAR, has been suggested as a novel biomarker of low-grade inflammation. Activation of the immune system has been proposed to contribute to the development of depression and suicidal behavior. In order to identify depressed and suicidal individuals who could benefit from an anti-inflammatory treatment, a reliable biomarker of low-grade inflammation is vital. This study evaluates plasma suPAR levels as a biomarker of low-grade inflammation in patients with major depressive disorder and in patients who recently attempted suicide. The plasma suPAR and an established biomarker, C reactive protein (CRP) of suicide attempters (n = 54), depressed patients (n = 19) and healthy controls (n = 19) was analyzed with enzyme-linked immunosorbent assays. The biomarker attributes of sensitivity and sensibility were evaluated using ROC curve analysis. Both the depressed patients and suicide attempters had increased plasma suPAR. The levels of suPAR discriminated better between controls and suicide attempters than did CRP. In the future, plasma suPAR might be a superior prognosticator regarding outcome of treatment applying conventional antidepressants in conjunction with anti-inflammatory drugs. PMID:26451727

  15. A multicenter cross-sectional study of circulating soluble urokinase receptor in Japanese patients with glomerular disease.

    PubMed

    Wada, Takehiko; Nangaku, Masaomi; Maruyama, Shoichi; Imai, Enyu; Shoji, Kumi; Kato, Sawako; Endo, Tomomi; Muso, Eri; Kamata, Kouju; Yokoyama, Hitoshi; Fujimoto, Keiji; Obata, Yoko; Nishino, Tomoya; Kato, Hideki; Uchida, Shunya; Sasatomi, Yoshie; Saito, Takao; Matsuo, Seiichi

    2014-03-01

    Elevated serum-soluble urokinase receptor (suPAR) levels have been described in patients with focal segmental glomerulosclerosis (FSGS) in several different cohorts. However, it remains unclear whether this is the case for Japanese patients and whether circulating suPAR can be clinically useful as a diagnostic marker. To determine this, we measured serum suPAR levels in 69 Japanese patients with biopsy-proven glomerular diseases in a cross-sectional manner. The serum suPAR levels showed a significant inverse correlation with renal function by univariate (R(2) of 0.242) and multivariate (β=0.226) analyses. Even after excluding patients with renal dysfunction, no significant difference in the suPAR levels was detected among the groups. Receiver operating characteristic analysis and measures of the diagnostic test performance showed that suPAR was not a useful parameter for differentiating FSGS from the other glomerular diseases (AUC-ROC: 0.621), although a small subgroup analysis showed that patients with FSGS, treated with steroids and/or immunosuppressants, had significantly lower suPAR levels. Patients with ANCA-associated glomerulonephritis had significantly higher levels of suPAR compared with the other disease groups, which may be owing to their lower renal function and systemic inflammation. Thus, suPAR levels are significantly affected by renal function and have little diagnostic value even in patients with normal renal function. PMID:24429394

  16. Proximity oscillations of complement type 4 (alphaX beta2) and urokinase receptors on migrating neutrophils.

    PubMed Central

    Kindzelskii, A L; Eszes, M M; Todd, R F; Petty, H R

    1997-01-01

    Migrating neutrophils utilize beta2 integrins for substrate attachment and urokinase receptors (uPAR) to focus pericellular proteolysis. Our studies show that CR3 associates with uPAR on resting cells, whereas uPAR associates with CR4 at lamellipodia of migrating cells. Using resonance energy transfer (RET) microscopy, we show that the molecular proximity between CR4 and uPAR oscillates on migrating cells, thus suggesting that CR4 molecules periodically bind/release uPAR. Cell contact with fibrinogen, endothelial cells, chemotactic factors and indomethacin, and treatment with sub-optimal doses of signal transduction inhibitors, affect the oscillations' period, amplitude, and/or waveform. The oscillations were indistinguishable in period and 180 degrees out-of-phase with cytosolic NAD(P)H autofluorescence oscillations. Thus, CR4 and CR3 identify a neutrophil's axis of migration and CR4 may restrain uPAR at lamellipodia. Oscillations in signal transduction and energy metabolism may coordinate cell adherence, local proteolysis, oxidant release, actin assembly, and cell extension. Images FIGURE 1 PMID:9336173

  17. A high-affinity receptor for urokinase plasminogen activator on human keratinocytes: characterization and potential modulation during migration.

    PubMed Central

    McNeill, H; Jensen, P J

    1990-01-01

    Low passage cultures of normal human keratinocytes produce several components of the plasminogen activator/plasmin proteolytic cascade, including urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA), and two specific inhibitors. Studies here presented demonstrate that these cells also contain a high-affinity (Kd = 3 x 10(-10) M) plasma membrane-binding site for uPA. High molecular weight uPA, either as the single-chain precursor or two-chain activated form, bound to the receptor; however, low molecular weight (33 kD) uPA, tPA, or epidermal growth factor did not compete for binding, demonstrating specificity. Acid treatment, which removed endogenous uPA from the receptor, was required to detect maximal binding (45,000 sites per cell). To investigate the possibility that the uPA receptor on keratinocytes may be involved in epithelial migration during wound repair, cultures were wounded and allowed to migrate into the wounded site. Binding sites for uPA were localized by autoradiographic analysis of 125I-uPA binding as well as by immunocytochemical studies using anti-uPA IgG. With both techniques uPA binding sites were detected selectively on the plasma membrane of cells at the leading edge of the migrating epithelial sheet. This localization pattern suggests that uPA receptor expression on keratinocytes may be coupled to cell migration during cutaneous wounding. Images PMID:1965151

  18. Structure-based Engineering of Species Selectivity in the Interaction Between Urokinase and its Receptor: Implication for Preclinical Cancer Therapy

    SciTech Connect

    Lin, L.; Gardsvoll, H; Huai, Q; Huang, M; Ploug, M

    2010-01-01

    The high affinity interaction between the urokinase-type plasminogen activator (uPA) and its glycolipid-anchored receptor (uPAR) is decisive for cell surface-associated plasminogen activation. Because plasmin activity controls fibrinolysis in a variety of pathological conditions, including cancer and wound healing, several intervention studies have focused on targeting the uPA {center_dot} uPAR interaction in vivo. Evaluations of such studies in xenotransplanted tumor models are, however, complicated by the pronounced species selectivity in this interaction. We now report the molecular basis underlying this difference by solving the crystal structure for the murine uPA {center_dot} uPAR complex and demonstrate by extensive surface plasmon resonance studies that the kinetic rate constants for this interaction can be swapped completely between these orthologs by exchanging only two residues. This study not only discloses the structural basis required for a successful rational design of the species selectivity in the uPA {center_dot} uPAR interaction, which is highly relevant for functional studies in mouse models, but it also suggests the possible development of general inhibitors that will target the uPA {center_dot} uPAR interaction across species barriers.

  19. Zinc phthalocyanine conjugated with the amino-terminal fragment of urokinase for tumor-targeting photodynamic therapy.

    PubMed

    Chen, Zhuo; Xu, Peng; Chen, Jincan; Chen, Hongwei; Hu, Ping; Chen, Xueyuan; Lin, Lin; Huang, Yunmei; Zheng, Ke; Zhou, Shanyong; Li, Rui; Chen, Song; Liu, Jianyong; Xue, Jinping; Huang, Mingdong

    2014-10-01

    Photodynamic therapy (PDT) has attracted much interest for the treatment of cancer due to the increased incidence of multidrug resistance and systemic toxicity in conventional chemotherapy. Phthalocyanine (Pc) is one of main classes of photosensitizers for PDT and possesses optimal photophysical and photochemical properties. A higher specificity can ideally be achieved when Pcs are targeted towards tumor-specific receptors, which may also facilitate specific drug delivery. Herein, we develop a simple and unique strategy to prepare a hydrophilic tumor-targeting photosensitizer ATF-ZnPc by covalently coupling zinc phthalocyanine (ZnPc) to the amino-terminal fragment (ATF) of urokinase-type plasminogen activator (uPA), a fragment responsible for uPA receptor (uPAR, a biomarker overexpressed in cancer cells), through the carboxyl groups of ATF. We demonstrate the high efficacy of this tumor-targeting PDT agent for the inhibition of tumor growth both in vitro and in vivo. Our in vivo optical imaging results using H22 tumor-bearing mice show clearly the selective accumulation of ATF-ZnPc in tumor region, thereby revealing the great potential of ATF-ZnPc for clinical applications such as cancer detection and guidance of tumor resection in addition to photodynamic treatment. PMID:24969665

  20. Transforming Growth Factor-Beta and Urokinase-Type Plasminogen Activator: Dangerous Partners in Tumorigenesis—Implications in Skin Cancer

    PubMed Central

    Santibanez, Juan F.

    2013-01-01

    Transforming growth factor-beta (TGF-β) is a pleiotropic factor, with several different roles in health and disease. TGF-β has been postulated as a dual factor in tumor progression, since it represses epithelial tumor development in early stages, whereas it stimulates tumor progression in advanced stages. During tumorigenesis, cancer cells acquire the capacity to migrate and invade surrounding tissues and to metastasize different organs. The urokinase-type plasminogen activator (uPA) system, comprising uPA, the uPA cell surface receptor, and plasminogen-plasmin, is involved in the proteolytic degradation of the extracellular matrix and regulates key cellular events by activating intracellular signal pathways, which together allow cancer cells to survive, thus, enhancing cell malignance during tumor progression. Due to their importance, uPA and its receptor are tightly transcriptionally regulated in normal development, but are deregulated in cancer, when their activity and expression are related to further development of cancer. TGF-β regulates uPA expression in cancer cells, while uPA, by plasminogen activation, may activate the secreted latent TGF-β, thus, producing a pernicious cycle which contributes to the enhancement of tumor progression. Here we review the specific roles and the interplay between TGF-β and uPA system in cancer cells and their implication in skin cancer. PMID:23984088

  1. Multifunctional roles of urokinase plasminogen activator (uPA) in cancer stemness and chemoresistance of pancreatic cancer

    PubMed Central

    Asuthkar, Swapna; Stepanova, Victoria; Lebedeva, Tatiana; Holterman, AiXuan L.; Estes, Norman; Cines, Douglas B.; Rao, Jasti S.; Gondi, Christopher S.

    2013-01-01

    Pancreatic ductal adenocarcinoma (PDAC) is almost always lethal. One of the underlying reasons for this lethality is believed to be the presence of cancer stem cells (CSC), which impart chemoresistance and promote recurrence, but the mechanisms responsible are unclear. Recently the poor prognosis of PDAC has been correlated with increased expression of urokinase plasminogen activator (uPA). In the present study we examine the role of uPA in the generation of PDAC CSC. We observe a subset of cells identifiable as a side population (SP) when sorted by flow cytometry of MIA PaCa-2 and PANC-1 pancreatic cancer cells that possess the properties of CSC. A large fraction of these SP cells are CD44 and CD24 positive, are gemcitabine resistant, possess sphere-forming ability, and exhibit increased tumorigenicity, known characteristics of cancer stemness. Increased tumorigenicity and gemcitabine resistance decrease after suppression of uPA. We observe that uPA interacts directly with transcription factors LIM homeobox-2 (Lhx2), homeobox transcription factor A5 (HOXA5), and Hey to possibly promote cancer stemness. uPA regulates Lhx2 expression by suppressing expression of miR-124 and p53 expression by repressing its promoter by inactivating HOXA5. These results demonstrate that regulation of gene transcription by uPA contributes to cancer stemness and clinical lethality. PMID:23864708

  2. Risk Factors Associated with Serum Levels of the Inflammatory Biomarker Soluble Urokinase Plasminogen Activator Receptor in a General Population

    PubMed Central

    Haupt, Thomas H; Kallemose, Thomas; Ladelund, Steen; Rasmussen, Line JH; Thorball, Christian W; Andersen, Ove; Pisinger, Charlotta; Eugen-Olsen, Jesper

    2014-01-01

    The soluble urokinase plasminogen activator receptor (suPAR) is a biomarker of mortality risk in various patient populations. However, little is known about the implications of lifestyle for suPAR levels in the general population. Lifestyle, demographic, and cardiovascular disease (CVD) risk factor data were collected from 5,538 participants in the Danish population-based Inter99 study. Their suPAR levels were measured using a sandwich enzyme-linked immunosorbent assay. In the final adjusted model, smoking and morbid obesity were strongly associated with higher suPAR levels (P < 0.001). An unhealthy diet and alcohol abstinence in men were also associated with higher suPAR levels. Physical activity in leisure time had a modest impact on suPAR levels in univariate analysis, but not in the final adjusted model. In conclusion, smoking and morbid obesity were strongly associated with higher serum suPAR levels in this general population. Diet and alcohol consumption also seemed to impact suPAR levels. Lifestyle changes are likely to affect suPAR since ex-smokers had suPAR levels comparable to those of never-smokers. PMID:25574132

  3. In vivo effects of urease-producing bacteria involved with the pathogenesis of infection-induced urolithiasis on renal urokinase and sialidase activity.

    PubMed

    du Toit, P J; van Aswegen, C H; Nel, J A; Steyn, P L; Ligthelm, A J; du Plessis, D J

    1995-01-01

    Many hypotheses have been proposed for renal stone formation. It has been argued that with infection-induced renal stones the hydrolysis of urea by bacterial urease increases urinary pH, with consequent stone formation. Unfortunately, this theory is not applicable to the micro-organisms that do not produce urease (e.g. Escherichia coli). It has been recently reported that E. coli reduces the urinary urokinase activity of male rats, but does not influence the urinary sialidase activity. This study has now been expanded to the urease-producing bacteria Proteus mirabilis, Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa and Micrococcus luteus. Subcutaneous injections with these bacteria were found to significantly (P < 0.003) reduce the UK activity of extrarenally obstructed kidneys. The urease-producing mammalian skin bacterium, M. luteus, was, however, the exception (P = 0.1079). In contrast to S. epidermidis, P. aeruginosa and M. luteus (P < 0.0213), P. mirabilis and S. aureus had no effect on renal sialidase activity (P < 0.4047). These results may explain why Proteus species are predominant in infection-induced renal stones. According to the urokinase-sialidase hypothesis, a decrease in urinary urokinase activity should increase the uromucoid levels, whilst no effect on the urinary sialidase activity should favour conversion of urinary uromucoid to mineralizable matrix. These conditions may lead to renal stone formation. An increase in urinary pH resulting from urease-producing micro-organisms will increase salt precipitation on the uromucoid. It is thus concluded that urease-producing bacteria may play a double role in renal stone formation. PMID:8839391

  4. Cigarette Smoke and the Induction of Urokinase Plasminogen Activator Receptor In Vivo: Selective Contribution of Isoforms to Bronchial Epithelial Phenotype.

    PubMed

    Portelli, Michael A; Stewart, Ceri E; Hall, Ian P; Brightling, Christopher E; Sayers, Ian

    2015-08-01

    The urokinase plasminogen activator receptor (uPAR) gene (PLAUR) has been identified as an asthma susceptibility gene, with polymorphisms within that gene being associated with baseline lung function, lung function decline, and lung function in a smoking population. Soluble cleaved uPAR (scuPAR), a molecule identified as a marker of increased morbidity and mortality in a number of diseases, has been shown to be elevated in the airways of patients with asthma and in patients with chronic obstructive pulmonary disease. However, the functionality of soluble receptor isoforms and their relationship with an important initiator for obstructive lung disease, cigarette smoke, remains undefined. In this study, we set out to determine the effect of cigarette smoke on soluble uPAR isoforms, its regulatory pathway and the resultant effect on bronchial epithelial cell function. We identified a positive association between cigarette pack-years and uPAR expression in the airway bronchial epithelium of biopsies from patients with asthma (n = 27; P = 0.0485). In vitro, cigarette smoke promoted cleavage of uPAR from the surface of bronchial epithelial cells (1.5× induction; P < 0.0001) and induced the soluble spliced isoform through changes in messenger RNA expression (∼2× change; P < 0.001), driven by loss of endogenous 3' untranslated region suppression. Elevated expression of the soluble isoforms resulted in a proremodeling cell phenotype, characterized by increased proliferation and matrix metalloproteinase-9 expression in primary bronchial epithelial cells. This suggests that cigarette smoke elevates soluble receptor isoforms in bronchial epithelial cells through direct (cleavage) and indirect (messenger RNA expression) means. These findings provide further insight into how cigarette smoke may influence changes in the airways of importance to airway remodeling and obstructive lung disease progression. PMID:25490122

  5. Serum Soluble Urokinase-Type Plasminogen Activator Receptor Levels and Idiopathic FSGS in Children: A Single-Center Report

    PubMed Central

    Price, Heather E.; Gallon, Lorenzo; Langman, Craig B.

    2013-01-01

    Summary Background and objectives FSGS is the primary cause of childhood nephrotic syndrome leading to ESRD. Permeability factors, including circulating serum soluble urokinase-type plasminogen activator receptor (suPAR), have been postulated as putative causes in adults with primary FSGS. Similar results have yet to be proven in children. Design, setting, participants, & measurements This cross-sectional single-center study assessed the association of serum suPAR in children with FSGS or other glomerular and nonglomerular kidney diseases. Results This study examined 110 samples retrieved from 99 individuals (between January 2011 and April 2012), aged 1–21 years; of these individuals, 20 had primary FSGS, 24 had non-FSGS glomerular disease, 26 had nonglomerular kidney disease, and 29 were healthy controls. suPAR levels were not significantly different in children with FSGS, non-FSGS glomerular disease, and healthy controls (P>0.05). However, suPAR levels (median [25%–75%]) were higher in children with nonglomerular kidney disease (3385 pg/ml [2695–4392]) versus FSGS (2487 pg/ml [2191–3351]; P<0.05). Female patients with nephrotic-range proteinuria (U-Pr/Cr >2) had lower suPAR levels than those without proteinuria (2380 pg/ml [2116–2571] versus 3125 pg/ml [2516–4198], respectively; P<0.001). This trend was not seen among male participants; suPAR levels in all female participants were lower than in male participants (P=0.03). Thirty-four patients studied were kidney transplant recipients; transplant status was not associated with suPAR levels in patients with FSGS or non-FSGS diagnoses, independent of proteinuria, race, or sex (P>0.05). Conclusions On the basis of these results, circulating suPAR is unlikely the leading cause for childhood idiopathic FSGS. PMID:23620441

  6. Cytokines induce urokinase-dependent adhesion of human myeloid cells. A regulatory role for plasminogen activator inhibitors.

    PubMed Central

    Waltz, D A; Sailor, L Z; Chapman, H A

    1993-01-01

    Differentiation of monocytic precursors often results in adhesive properties thought to be important in migration. In this study, the influence of cytokines, known to induce macrophage differentiation, on the adhesiveness of the monocytic cell line U937 was examined in vitro. Despite development of a macrophage morphology, < 5% of cytokine-stimulated U937 cells were adherent at 24 h. Addition of 1-10 nM urokinase-type plasminogen activator (uPA) induced adherence in the presence of transforming growth factor type beta-1, 1,25-(OH)2 vitamin D3, granulocyte macrophage colony-stimulating factor, or tumor necrosis factor alpha. uPA-dependent adhesiveness was reversible after 24 h of stimulation with cytokines and uPA as adherence was prevented by the subsequent addition of anti-uPA antibodies. Adherence induced by diisopropylfluorophosphate-inactivated uPA was severalfold greater than that seen with active uPA. This difference was largely due to cell-surface turnover of active uPA complexed with plasminogen activator inhibitor (PAI). These data indicate that cytokines prime monocyte progenitors for uPA receptor-mediated signals leading to adherence, continued uPA receptor occupancy is required for adherence, and PAI decreases adherence by promoting clearance of uPA/PAI complexes. Thus the interaction of uPA and PAI at the cell surface, known to affect extracellular matrix proteolysis and hence myeloid cell migration, also regulates adhesion. The coordinated regulation of these two uPA functions by PAI may enhance the migratory potential of monocytic cells. Images PMID:8386190

  7. Thrombosis recanalization by paeoniflorin through the upregulation of urokinase-type plasminogen activator via the MAPK signaling pathway

    PubMed Central

    YE, SONGSHAN; MAO, BINGYU; YANG, LEI; FU, WEIYUN; HOU, JUNRAN

    2016-01-01

    Paeoniflorin, the major component of Paeonia lactiflora pall, has previously been reported to prevent thrombosis. Plasminogen activator urokinase (uPA) is a serine protease that markedly facilitates normal thrombosis resolution. Paeoniflorin and uPA have been linked to the mitogen-activated protein kinase (MAPK) signaling pathway. In the current study, the influence of paeoniflorin on the expression of uPA was investigated and the underlying regulatory mechanism was preliminarily determined. The prothrombotic state of the model animals treated with paeoniflorin were assessed by enzyme-linked immunosorbent assay (ELISA). Additionally, the cytotoxicity of paeoniflorin on human umbilical vein endothelial cell (HUVEC) cultures was estimated using a methyl thiazolyl tetrazolium assay and the possible pathways involved in the interaction between paeoniflorin and uPA were evaluated using western blot analysis. The ELISA results demonstrated that the levels of 6-keto prostaglandin F1a, fibronectin and uPA were significantly upregulated by treatment with paeoniflorin compared with control (P<0.05). By contrast, the expression of fibrinogen, D-dimer and thromboxane B2 were inhibited. With an increase in the concentration of paeoniflorin the cell viability of HUVECs decreased gradually. The results of western blot analysis demonstrated that paeoniflorin increased the phosphorylation of MAPK 14 (p38) and MAPK 8 (JNK). The present study demonstrated that paeoniflorin has the potential to improve the prethrombotic state and recanalize thrombosis by increasing the expression of uPA, which may be mediated via regulation of the p38 and JNK MAPK signaling pathways. However, this treatment effect was dependent on the concentration of paeoniflorin used, an unsuitable concentration of the agent would result in a negative effect on the anti-thrombosis pathways. PMID:27082639

  8. Overexpression of urokinase receptor increases matrix invasion without altering cell migration in a human osteosarcoma cell line.

    PubMed

    Karikó, K; Kuo, A; Boyd, D; Okada, S S; Cines, D B; Barnathan, E S

    1993-07-01

    Proteolysis triggered by receptor-bound urokinase-type plasminogen activator (uPA) involves a cascade of species-specific molecular interactions. To study the role of the uPA receptor (uPAR) in such interactions, a human osteosarcoma cell line (HOS), which normally expresses low levels of uPAR, was transfected with human uPAR complementary DNA. One of several stably transformed clonal cells lines, designated 2A2, was characterized and compared to the parental HOS, revealing the following: (a) stable incorporation of uPAR complementary DNA into the genome demonstrated by Southern blot analysis; (b) a 10-fold increase in steady state mRNA levels of uPAR assessed by Northern blot analysis; (c) a 2-fold increase in the surface expression of glycosylphosphatidylinositol anchored uPAR protein determined by enzyme-linked immunosorbent assay and by the specific binding of radiolabeled single chain uPA; (d) a 2-fold increase in internalization and degradation of radiolabeled uPA/PAI-1 complexes; and (e) a 2-fold increase in receptor-bound uPA-mediated plasmin generation measured by the cleavage of a chromogenic substrate and degradation of 125I-labeled laminin. The involvement of uPAR in cellular processes was determined by comparing 2A2 and HOS cells in in vitro migration and invasion assays. The migration of 2A2 cells were slower on fibronectin-coated surfaces in a linear under-agarose assay, but both cell lines migrated at the same rate on uncoated polycarbonate filters in Boyden chamber assays. In the invasion experiments, 4 times more 2A2 than HOS cells penetrated through the barrier of reconstituted basement membrane Matrigel. These data suggest that uPAR does not potentiate random cell migration but facilitates matrix degradation and subsequent cell invasion. PMID:8391387

  9. CFTR suppresses tumor progression through miR-193b targeting urokinase plasminogen activator (uPA) in prostate cancer.

    PubMed

    Xie, C; Jiang, X H; Zhang, J T; Sun, T T; Dong, J D; Sanders, A J; Diao, R Y; Wang, Y; Fok, K L; Tsang, L L; Yu, M K; Zhang, X H; Chung, Y W; Ye, L; Zhao, M Y; Guo, J H; Xiao, Z J; Lan, H Y; Ng, C F; Lau, K M; Cai, Z M; Jiang, W G; Chan, H C

    2013-05-01

    Cystic fibrosis (CF) transmembrane conductance regulator (CFTR) is expressed in the epithelial cells of a wide range of organs/tissues from which most cancers are derived. Although accumulating reports have indicated the association of cancer incidence with genetic variations in CFTR gene, the exact role of CFTR in cancer development and the possible underlying mechanism have not been elucidated. Here, we report that CFTR expression is significantly decreased in both prostate cancer cell lines and human prostate cancer tissue samples. Overexpression of CFTR in prostate cancer cell lines suppresses tumor progression (cell growth, adhesion and migration), whereas knockdown of CFTR leads to enhanced malignancies both in vitro and in vivo. In addition, we demonstrate that CFTR knockdown-enhanced cell proliferation, cell invasion and migration are significantly reversed by antibodies against either urokinase plasminogen activator (uPA) or uPA receptor (uPAR), which are known to be involved in various malignant traits of cancer development. More interestingly, overexpression of CFTR suppresses uPA by upregulating the recently described tumor suppressor microRNA-193b (miR-193b), and overexpression of pre-miR-193b significantly reverses CFTR knockdown-enhanced malignant phenotype and abrogates elevated uPA activity in prostate cancer cell line. Finally, we show that CFTR gene transfer results in significant tumor repression in prostate cancer xenografts in vivo. Taken together, the present study has demonstrated a previously undefined tumor-suppressing role of CFTR and its involvement in regulation of miR-193b in prostate cancer development. PMID:22797075

  10. Prognostic relevance of urokinase plasminogen activator detection in micrometastatic cells in the bone marrow of patients with primary breast cancer.

    PubMed Central

    Solomayer, E. F.; Diel, I. J.; Wallwiener, D.; Bode, S.; Meyberg, G.; Sillem, M.; Gollan, C.; Kramer, M. D.; Krainick, U.; Bastert, G.

    1997-01-01

    Patients with an elevated level of urokinase plasminogen activator (uPA) in breast cancer tissue have an adverse prognosis. This study evaluated the prognostic relevance of uPA detection in disseminated tumour cells in bone marrow. Bone marrow was sampled intraoperatively from both iliac crests in 280 patients with primary breast cancer. Interphase cells were enhanced and stained immunocytologically with two antibodies: 2E11, which detects TAG 12--a tumour-associated glycoprotein typically expressed by almost all breast cancer cells--and the anti-uPA antibody HD-UK9. Thirty-five of the 2E11-positive women (n = 132, 47%) developed metastatic disease (median follow-up time 44 months). Of these, most were uPA positive (n = 23, 65%) and only 12 were uPA negative. Patients with uPA-positive cells in bone marrow (n = 98, 35%) had a significantly shorter metastasis-free interval (36 months) than women who were uPA negative (44.5 months). The worst prognosis was seen in patients positive for both markers (29.5 months), followed by those who were uPA negative and 2E11 positive (37 months). The detection of uPA on disseminated tumour cells characterizes a subgroup of patients with an even worse prognosis, who should undergo more aggressive adjuvant systemic therapy. For the first time, it was possible to evaluate an important qualitative parameter involved in the process of breast cancer metastases. Images Figure 1 PMID:9310251

  11. Cloud regimes as phase transitions

    NASA Astrophysics Data System (ADS)

    Stechmann, Samuel N.; Hottovy, Scott

    2016-06-01

    Clouds are repeatedly identified as a leading source of uncertainty in future climate predictions. Of particular importance are stratocumulus clouds, which can appear as either (i) closed cells that reflect solar radiation back to space or (ii) open cells that allow solar radiation to reach the Earth's surface. Here we show that these clouds regimes -- open versus closed cells -- fit the paradigm of a phase transition. In addition, this paradigm characterizes pockets of open cells as the interface between the open- and closed-cell regimes, and it identifies shallow cumulus clouds as a regime of higher variability. This behavior can be understood using an idealized model for the dynamics of atmospheric water as a stochastic diffusion process. With this new conceptual viewpoint, ideas from statistical mechanics could potentially be used for understanding uncertainties related to clouds in the climate system and climate predictions.

  12. Inhibitory effect of berberine on the invasion of human lung cancer cells via decreased productions of urokinase-plasminogen activator and matrix metalloproteinase-2

    SciTech Connect

    Peng, P.-L.; Hsieh, Y.-S.; Wang, C.-J.; Hsu, J.-L.; Chou, F.-P. . E-mail: fpchou@csmu.edu.tw

    2006-07-01

    Berberine, a compound isolated from medicinal herbs, has been reported with many pharmacological effects related to anti-cancer and anti-inflammation capabilities. In this study, we observed that berberine exerted a dose- and time-dependent inhibitory effect on the motility and invasion ability of a highly metastatic A549 cells under non-cytotoxic concentrations. In cancer cell migration and invasion process, matrix-degrading proteinases are required. A549 cell treated with berberine at various concentrations showed reduced ECM proteinases including matrix metalloproteinase-2 (MMP2) and urokinase-plasminogen activator (u-PA) by gelatin and casein zymography analysis. The inhibitory effect is likely to be at the transcriptional level, since the reduction in the transcripts levels was corresponding to the proteins. Moreover, berberine also exerted its action via regulating tissue inhibitor of metalloproteinase-2 (TIMP-2) and urokinase-plasminogen activator inhibitor (PAI). The upstream mediators of the effect involved c-jun, c-fos and NF-{kappa}B, as evidenced by reduced phosphorylation of the proteins. These findings suggest that berberine possesses an anti-metastatic effect in non-small lung cancer cell and may, therefore, be helpful in clinical treatment.

  13. Soluble Urokinase-Type Plasminogen Activator Receptor Plasma Concentration May Predict Susceptibility to High Altitude Pulmonary Edema

    PubMed Central

    Zügel, Stefanie; Schoeb, Michele; Auinger, Katja; Dehnert, Christoph; Maggiorini, Marco

    2016-01-01

    Introduction. Acute exposure to high altitude induces inflammation. However, the relationship between inflammation and high altitude related illness such as high altitude pulmonary edema (HAPE) and acute mountain sickness (AMS) is poorly understood. We tested if soluble urokinase-type plasminogen activator receptor (suPAR) plasma concentration, a prognostic factor for cardiovascular disease and marker for low grade activation of leukocytes, will predict susceptibility to HAPE and AMS. Methods. 41 healthy mountaineers were examined at sea level (SL, 446 m) and 24 h after rapid ascent to 4559 m (HA). 24/41 subjects had a history of HAPE and were thus considered HAPE-susceptible (HAPE-s). Out of the latter, 10/24 HAPE-s subjects were randomly chosen to suppress the inflammatory cascade with dexamethasone 8 mg bid 24 h prior to ascent. Results. Acute hypoxic exposure led to an acute inflammatory reaction represented by an increase in suPAR (1.9 ± 0.4 at SL versus 2.3 ± 0.5 at HA, p < 0.01), CRP (0.7 ± 0.5 at SL versus 3.6 ± 4.6 at HA, p < 0.01), and IL-6 (0.8 ± 0.4 at SL versus 3.3 ± 4.9 at HA, p < 0.01) in all subjects except those receiving dexamethasone. The ascent associated decrease in PaO2 correlated with the increase in IL-6 (r = 0.46, p < 0.001), but not suPAR (r = 0.27, p = 0.08); the increase in IL-6 was not correlated with suPAR (r = 0.16, p = 0.24). Baseline suPAR plasma concentration was higher in the HAPE-s group (2.0 ± 0.4 versus 1.8 ± 0.4, p = 0.04); no difference was found for CRP and IL-6 and for subjects developing AMS. Conclusion. High altitude exposure leads to an increase in suPAR plasma concentration, with the missing correlation between suPAR and IL-6 suggesting a cytokine independent, leukocyte mediated mechanism of low grade inflammation. The correlation between IL-6 and PaO2 suggests a direct effect of hypoxia, which is not the case for suPAR. However, suPAR plasma concentration measured before hypoxic exposure may predict

  14. Tissue and urokinase plasminogen activators instigate the degeneration of retinal ganglion cells in a mouse model of glaucoma.

    PubMed

    Chintala, Shravan K

    2016-02-01

    Elevated intraocular pressure (IOP) promotes the degeneration of retinal ganglion cells (RGCs) during the progression of Primary Open-Angle Glaucoma (POAG). However, the molecular mechanisms underpinning IOP-mediated degeneration of RGCs remain unclear. Therefore, by employing a mouse model of POAG, this study examined whether elevated IOP promotes the degeneration of RGCs by up-regulating tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA) in the retina. IOP was elevated in mouse eyes by injecting fluorescent-microbeads into the anterior chamber. Once a week, for eight weeks, IOP in mouse eyes was measured by using Tono-Pen XL. At various time periods after injecting microbeads, proteolytic activity of tPA and uPA in retinal protein extracts was determined by fibrinogen/plasminogen zymography assays. Localization of tPA and uPA, and their receptor LRP-1 (low-density receptor-related protein-1) in the retina was determined by immunohistochemistry. RGCs' degeneration was assessed by immunostaining with antibodies against Brn3a. Injection of microbeads into the anterior chamber led to a progressive elevation in IOP, increased the proteolytic activity of tPA and uPA in the retina, activated plasminogen into plasmin, and promoted a significant degeneration of RGCs. Elevated IOP up-regulated tPA and LRP-1 in RGCs, and uPA in astrocytes. At four weeks after injecting microbeads, RAP (receptor associated protein; 0.5 and 1.0 μM) or tPA-Stop (1.0 and 4.0 μM) was injected into the vitreous humor. Treatment of IOP-elevated eyes with RAP led to a significant decrease in proteolytic activity of both tPA and uPA, and a significant decrease in IOP-mediated degeneration of RGCs. Also, treatment of IOP-elevated eyes with tPA-Stop decreased the proteolytic activity of both tPA and uPA, and, in turn, significantly attenuated IOP-mediated degeneration of RGCs. Results presented in this study provide evidence that elevated IOP promotes the degeneration of

  15. Plasma Levels of Soluble Urokinase-Type Plasminogen Activator Receptor Associate with the Clinical Severity of Acute Puumala Hantavirus Infection

    PubMed Central

    Outinen, Tuula K.; Tervo, Laura; Mäkelä, Satu; Huttunen, Reetta; Mäenpää, Niina; Huhtala, Heini; Vaheri, Antti; Mustonen, Jukka; Aittoniemi, Janne

    2013-01-01

    Objectives Urokinase-type plasminogen activator receptor is a multifunctional glycoprotein, the expression of which is increased during inflammation. It is known to bind to β3-integrins, which are elementary for the cellular entry of hantaviruses. Plasma soluble form of the receptor (suPAR) levels were evaluated as a predictor of severe Puumala hantavirus (PUUV) infection and as a possible factor involved in the pathogenesis of the disease. Design A single-centre prospective cohort study. Subjects and Methods Plasma suPAR levels were measured twice during the acute phase and once during the convalescence in 97 patients with serologically confirmed acute PUUV infection using a commercial enzyme-linked immunosorbent assay (ELISA). Results The plasma suPAR levels were significantly higher during the acute phase compared to the control values after the hospitalization (median 8.7 ng/ml, range 4.0–18.2 ng/ml vs. median 4.7 ng/ml, range 2.4–12.2 ng/ml, P<0.001). The maximum suPAR levels correlated with several variables reflecting the severity of the disease. There was a positive correlation with maximum leukocyte count (r = 0.475, p<0.001), maximum plasma creatinine concentration (r = 0.378, p<0.001), change in weight during the hospitalization (r = 0.406, p<0.001) and the length of hospitalization (r = 0.325, p = 0.001), and an inverse correlation with minimum platelet count (r = −0.325, p = 0.001) and minimum hematocrit (r = −0.369, p<0.001). Conclusion Plasma suPAR values are markedly increased during acute PUUV infection and associate with the severity of the disease. The overexpression of suPAR possibly activates β3-integrin in PUUV infection, and thus might be involved in the pathogenesis of the disease. PMID:23990945

  16. Epitope-mapped monoclonal antibodies as tools for functional and morphological analyses of the human urokinase receptor in tumor tissue.

    PubMed Central

    Luther, T.; Magdolen, V.; Albrecht, S.; Kasper, M.; Riemer, C.; Kessler, H.; Graeff, H.; Müller, M.; Schmitt, M.

    1997-01-01

    uPAR (CD87), the receptor for the urokinase-type plasminogen activator (uPA) facilitates tumor cell invasion and metastasis by focusing uPA proteolytic activity to the cell surface. As uPAR exists in various molecular forms, it is desirable to use well defined antibodies for analyses of uPAR antigen expression in human malignant tumors by immunological methods. Therefore, twelve monoclonal antibodies (MAbs) directed against uPAR were generated by using nonglycosylated, recombinant human uPAR (spanning amino acids 1 to 284), expressed in Escherichia coli, as the immunogen. The reaction pattern of these MAbs with the immunogen and a series of carboxyl-terminally truncated versions of uPAR demonstrated that at least six different epitopes of uPAR are recognized. All MAbs reacted under reducing conditions in immunoblot analyses with E. coli-expressed uPA and also with highly glycosylated, functionally intact, recombinant human uPAR expressed in Chinese hamster ovary (CHO) cells. Seven of the MAbs recognized CHO uPAR under nonreducing conditions as well. By flow cytofluorometric analyses, three of these MAbs were shown to bind to native human uPAR present on the cell surface of monocytoid U937 cells with MAb IIIF10 being the best. Saturation of uPAR with uPA on U937 cells completely blocked interaction of MAb IIIF10 with uPAR (mapped epitope, amino acids 52 to 60 of domain I of uPAR). In turn, preincubation of U937 cells with MAb IIIF10 efficiently reduced binding of uPA to uPAR, indicating that the epitope detected by MAb IIIF10 is located within or closely to the uPA-binding site of uPAR, and thus, this site may be a target to influence uPA/uPAR-mediated proteolysis in tumors. Binding of MAbs IID7 or IIIB11 (mapped epitope, amino acids 125 to 132 of domain II of uPAR) to uPAR is not affected when uPAR is occupied by uPA. As these MAbs reacted strongly with cellular uPAR antigen in formalin-fixed paraffin-embedded tumor sections, the domain-II-specific antibodies IID7

  17. Soluble Urokinase-Type Plasminogen Activator Receptor Plasma Concentration May Predict Susceptibility to High Altitude Pulmonary Edema.

    PubMed

    Hilty, Matthias Peter; Zügel, Stefanie; Schoeb, Michele; Auinger, Katja; Dehnert, Christoph; Maggiorini, Marco

    2016-01-01

    Introduction. Acute exposure to high altitude induces inflammation. However, the relationship between inflammation and high altitude related illness such as high altitude pulmonary edema (HAPE) and acute mountain sickness (AMS) is poorly understood. We tested if soluble urokinase-type plasminogen activator receptor (suPAR) plasma concentration, a prognostic factor for cardiovascular disease and marker for low grade activation of leukocytes, will predict susceptibility to HAPE and AMS. Methods. 41 healthy mountaineers were examined at sea level (SL, 446 m) and 24 h after rapid ascent to 4559 m (HA). 24/41 subjects had a history of HAPE and were thus considered HAPE-susceptible (HAPE-s). Out of the latter, 10/24 HAPE-s subjects were randomly chosen to suppress the inflammatory cascade with dexamethasone 8 mg bid 24 h prior to ascent. Results. Acute hypoxic exposure led to an acute inflammatory reaction represented by an increase in suPAR (1.9 ± 0.4 at SL versus 2.3 ± 0.5 at HA, p < 0.01), CRP (0.7 ± 0.5 at SL versus 3.6 ± 4.6 at HA, p < 0.01), and IL-6 (0.8 ± 0.4 at SL versus 3.3 ± 4.9 at HA, p < 0.01) in all subjects except those receiving dexamethasone. The ascent associated decrease in PaO2 correlated with the increase in IL-6 (r = 0.46, p < 0.001), but not suPAR (r = 0.27, p = 0.08); the increase in IL-6 was not correlated with suPAR (r = 0.16, p = 0.24). Baseline suPAR plasma concentration was higher in the HAPE-s group (2.0 ± 0.4 versus 1.8 ± 0.4, p = 0.04); no difference was found for CRP and IL-6 and for subjects developing AMS. Conclusion. High altitude exposure leads to an increase in suPAR plasma concentration, with the missing correlation between suPAR and IL-6 suggesting a cytokine independent, leukocyte mediated mechanism of low grade inflammation. The correlation between IL-6 and PaO2 suggests a direct effect of hypoxia, which is not the case for suPAR. However, suPAR plasma concentration measured before hypoxic exposure may predict

  18. Structural analysis and tissue localization of human C4.4A: a protein homologue of the urokinase receptor.

    PubMed Central

    Hansen, Line V; Gårdsvoll, Henrik; Nielsen, Boye S; Lund, Leif R; Danø, Keld; Jensen, Ole N; Ploug, Michael

    2004-01-01

    C4.4A, a structural homologue of the urokinase-type plasminogen activator receptor (uPAR), was originally identified as a metastasis-associated membrane protein, but little is known about its structural and functional properties. Therefore, we expressed, purified and characterized a soluble truncated form of human C4.4A, and used this protein to produce specific polyclonal anti-C4.4A antibodies. By immunohistochemistry we observed a pronounced surface staining for C4.4A in suprabasal keratinocytes of chronic human wounds and found C4.4A expression markedly upregulated in migrating keratinocytes during re-epithelisation of incisional skin wounds. Phorbol-ester-induced hyperplasia of mouse skin is also accompanied by a significant induction of C4.4A expression in the multilayered, suprabasal keratinocytes. C4.4A contains two Ly-6 (leucocyte antigen 6)/uPAR/alpha-neurotoxin modules. Our recombinant human C4.4A is extensively modified by post-translational glycosylation, which include 5-6 N-linked carbohydrates primarily located in or close to its second Ly-6/uPAR/alpha-neurotoxin module and approximately 15 O-linked carbohydrates clustered in a Ser/Thr/Pro-rich region at the C-terminus. A highly protease-sensitive region (Tyr200-Arg204) is located between these two clusters of N- and O-linked carbohydrates. The natural, glycolipid-anchored C4.4A from amnion membranes of human term placenta exhibits similar properties. Using recombinant, soluble C4.4A or MCF 7 cells, which express significant amounts of GPI-anchored C4.4A, we find no evidence for an interaction between C4.4A and uPA, a property suggested previously for rat C4.4A. Collectively these data indicate that C4.4A, although being a structural homologue of uPAR, is unlikely to have a functional overlap with uPAR. PMID:15012588

  19. The emerging climate change regime

    SciTech Connect

    Bodansky, D.M.

    1995-11-01

    The emerging climate change regime--with the UN Framework Convention on Climate Change (FCCC) at its core--reflects the substantial uncertainties, high stakes and complicated politics of the greenhouse warming issue. The regime represents a hedging strategy. On the one hand, it treats climate change as a potentially serious problem, and in response, creates a long-term, evolutionary process to encourage further research, promote national planning, increase public awareness, and help create a sense of community among states. But it requires very little by way of substantive--and potentially costly--mitigation or adaptation measures. Although the FCCC parties have agreed to negotiate additional commitments, substantial progress is unlikely without further developments in science, technology, and public opinion. The FCCC encourages such developments, and is capable of evolution and growth, should the political will to take stronger international action emerge. 120 refs., 3 tabs.

  20. Optics in the Relativistic Regime

    NASA Astrophysics Data System (ADS)

    Tajima, Toshiki

    2012-06-01

    Optics has extended the frontier of low energy physics. Here we present the progress in the opposite direction of relativistic intensity regime of optics. With intense and large energy laser, particles may be accelerated to high energies via laser wakefield acceleration (Tajima and Dawson, 1979) over a compact distance orders of magnitude shorter than the RF approach. We should be able to accelerate electrons (over 30m) and ions (over cm) toward TeV with an existing kJ laser. We can check Lorentz invariance in the ultrarelativistic regime. Further, laser allows us to explore the presence of weakly coupling fields such as Dark Matter and Dark Energy with an unprecedented sensitivity. We call this emerging capability as the Laser Particle Physics Paradigm (LP^3).

  1. Demystifying optimal dynamic treatment regimes.

    PubMed

    Moodie, Erica E M; Richardson, Thomas S; Stephens, David A

    2007-06-01

    A dynamic regime is a function that takes treatment and covariate history and baseline covariates as inputs and returns a decision to be made. Murphy (2003, Journal of the Royal Statistical Society, Series B 65, 331-366) and Robins (2004, Proceedings of the Second Seattle Symposium on Biostatistics, 189-326) have proposed models and developed semiparametric methods for making inference about the optimal regime in a multi-interval trial that provide clear advantages over traditional parametric approaches. We show that Murphy's model is a special case of Robins's and that the methods are closely related but not equivalent. Interesting features of the methods are highlighted using the Multicenter AIDS Cohort Study and through simulation. PMID:17688497

  2. Hall effect in hopping regime

    NASA Astrophysics Data System (ADS)

    Avdonin, A.; Skupiński, P.; Grasza, K.

    2016-02-01

    A simple description of the Hall effect in the hopping regime of conductivity in semiconductors is presented. Expressions for the Hall coefficient and Hall mobility are derived by considering averaged equilibrium electron transport in a single triangle of localization sites in a magnetic field. Dependence of the Hall coefficient is analyzed in a wide range of temperature and magnetic field values. Our theoretical result is applied to our experimental data on temperature dependence of Hall effect and Hall mobility in ZnO.

  3. The International Climate Change Regime

    NASA Astrophysics Data System (ADS)

    Yamin, Farhana; Depledge, Joanna

    2005-01-01

    Aimed at the increasing number of policy-makers, stakeholders, researchers, and other professionals working on climate change, this volume presents a detailed description and analysis of the international regime established in 1992 to combat the threat of global climate change. It provides a comprehensive accessible guide to a high-profile area of international law and politics, covering not only the obligations and rights of countries, but ongoing climate negotiations as well.

  4. Merging of Rhine flow regimes

    NASA Astrophysics Data System (ADS)

    Boessenkool, Berry; Bronstert, Axel; Bürger, Gerd

    2016-04-01

    The Rhine flow regime is changing: (a) in the alpine nival regime, snow melt floods occur earlier in the year and (b) in the pluvial middle-Rhine regime, rainfall induced flood magnitudes rise. The seasonality of each is currently separated in time, but it is conceivable that this may shift due to climate change. If extremes of both flood types coincide, this would create a new type of hydrologic extreme with disastrous consequences. Quantifying the probability for a future overlap of pluvial and nival floods is therefore of high relevance to society and particularly to reinsurance companies. In order to investigate possible changes in magnitude and timing of flood types, we are developing a chain of physical models for spatio-temporal combination of flood probabilities. As input, we aim to use stochastically downscaled temperature and rainfall extremes from climate model weather projections. Preliminary research shows a six-week forward-shift of peak discharge at the nival gauge Maxau in the past century. The aim of presenting our early-stage work as a poster is to induce an exchange of ideas with fellow scientists in close research disciplines.

  5. Optimization of Crystals of an Inhibitory Antibody of Urokinase Plasminogen Activator Receptor (uPAR) with Hydrogen Peroxide and Low Protein Concentration

    SciTech Connect

    Li, Yongdong; Shi, Xiaoli; Parry, Graham; Chen, Liqing; Callahan, Jennifer A.; Mazar, Andrew P.; Huang, Mingdong

    2010-07-19

    Optimization of protein crystal formation is often a necessary step leading to diffraction-quality crystals to enable collection of a full X-ray data set. Typical protein crystal optimization involves screening different components, e.g., pH, precipitants, and additives of the precipitant solution. Here we present an example using an inhibitory antibody of urokinase plasminogen activator receptor (uPAR) where such procedures did not yield diffracting crystals. In contrast, it was the treatment of the protein with hydrogen peroxide incubation and the protein concentration reduction that were found to be key factors in obtaining diffracting crystals. Final crystals diffracted to 1.75 {angstrom}, and belong to orthorhombic P212121 space group with unit cell parameters a = 37.162 {angstrom}, b = 84.474 {angstrom}, c = 134.030 {angstrom}, and contain one molecule of Fab fragment of anti-uro kinase receptor antibody in the asymmetric unit.

  6. Anti-Urokinase Receptor Antisense Oligonucleotide (uPAR-aODN) to Prevent and Cure Long-Term Space Exploration-Related Retinal Pathological Angiogenesis

    NASA Astrophysics Data System (ADS)

    Lazzarano, Stefano; Lulli, Matteo; Fibbi, Gabriella; Margheri, Francesca; Papucci, Laura; Serrati, Simona; Witort, Ewa; Chilla, Anastasia; Lapucci, Andrea; Donnini, Martino; Quaglierini, Paolo; Romiti, Alice; Specogna, Rebecca; Del Rosso, Mario; Capaccioli, Sergio

    2008-06-01

    Angiogenesis underlies a variety of physiological processes and its possible deregulation during long term space exploration needs to be investigated. Angiogenesis is a multistep process of new blood capillary formation, where degradation of the extracellular matrix (ECM) by proteolytic enzymes, including uPA (urokinase plasminogen activator) and opening the way to migration of endothelial cells (EC), is critical. Plasminogen activation system regulates angiogenesis by both uPA-driven ECM degradation and uPA receptor (uPAR). Microgravity and low dose irradiations promote tissue neoangiogeenesis and neovascularization is often common occurence in ophthalmologic pathologies. We have designed and patented the uPAR antisense oligonucleotide (aODN) and evaluated its antiangiogenetic activity by EC cellular migration and capillary morphogenesis assays. The uPAR aODN treatment caused a 75% inhibition of human microvascular EC migration and a complete inhibition of capillary morphogenesis, suggesting its therapeutic application to prevent neoangiogenesis-related ophthalmologic pathologies during space exploration.

  7. The Role of Urokinase Plasminogen Activator and Plasmin Activator Inhibitor-1 on Vein Wall Remodeling in Experimental Deep Vein Thrombosis

    PubMed Central

    Baldwin, Joe F.; Sood, Vikram; Elfline, Megan A.; Luke, Cathy E.; Dewyer, Nicholas A.; Diaz, Jose A.; Myers, Dan D.; Wakefield, Thomas; Henke, Peter K.

    2012-01-01

    OBJECTIVE Deep vein thrombosis (DVT) resolution instigates an inflammatory response, resulting in vessel wall damage and scarring. Urokinase-plasminogen activator (uPA) and its inhibitor, plasminogen activator inhibitor-1 (PAI-1), are integral components of the fibrinolytic system, essential for VT resolution. This study determined the vein wall response when exposed to increased and decreased plasmin activity. Methods A mouse inferior vena cava (IVC) ligation model in uPA −/− or PAI-1 −/− and their genetic wild types (B6/SvEv and C57/BL6, respectively) was used to create stasis thrombi, with tissue harvest at either 8 or 21d. Tissue analysis included gene expression of vascular smooth muscle cells (alpha SMA [αSMA], SM22) and endothelial marker (CD31), by real time PCR, ELISA, matrix metalloproteinase (MMP) -2 and 9 activity by zymography and vein wall collagen by picrosirius red histological analysis. A P < .05 was considered significant. RESULTS Thrombi were significantly larger in both 8d and 21d uPA −/− as compared to WT, and were significantly smaller in both 8 and 21d PAI-1 −/− as compared to WT. Correspondingly, 8d plasmin levels were reduced in half in uPA −/− and increased 3 fold in PAI-1 −/− when compared to respective WT thrombi (P < .05, N = 5 – 6). The endothelial marker CD31 was elevated 2 fold in PAI-1 −/− mice at 8d, but reduced 2.5 fold at 21d in uPA −/− as compared with WT (P = .02, N = 5 – 6), suggesting less endothelial preservation. Vein wall VSMC gene expression showed that 8d and 21d PAI-1 −/− mice had 2.3 and 3.8 fold more SM22 and 1.8 and 2.3 fold more αSMA expression than respective WT (P < .05, N = 5 – 7), as well as 1.8 fold increased αSMA (+) cells (N = 3 – 5, P ≤ .05). No significant difference in MMP2 or 9 activity was found in the PAI-1 −/− mice compared with WT, while 5.4 fold more MMP9 was present in 21d WT than 21d uPA −/− (P = .03, N = 5). Lastly, collagen was ~2 fold

  8. Stimulation of urokinase-type plasminogen activator receptor expression by PMA requires JNK1-dependent and -independent signaling modules.

    PubMed

    Gum, R; Juarez, J; Allgayer, H; Mazar, A; Wang, Y; Boyd, D

    1998-07-16

    The urokinase-type plasminogen activator receptor (u-PAR) has been implicated in tumor progression, and previous studies have shown that the expression of this gene is strongly up-regulated by PMA. Although the signaling mechanism by which PMA modulates u-PAR expression is not known, the effect of this phorbol ester on the expression of other genes has been ascribed to activation of the c-Raf-1-ERK signaling pathway. However, in the current study we examined an alternate possibility that the inductive effect of PMA on u-PAR expression also required a JNK1-dependent signaling cascade usually associated with stress-inducing stimuli. PMA treatment of the u-PAR-deficient OVCAR-3 ovarian cancer cells, which contain low JNK activities, resulted in a rapid (5 min) increase in JNK activity. Maximal JNK activity (12-fold induction) occurred after 30 min; this preceding the earliest detected rise in u-PAR protein (2 h). Dose-response studies with PMA also indicated that the increased JNK activity was tightly correlated with elevated u-PAR protein levels. The stimulation of u-PAR promoter activity by PMA required an intact upstream AP-1 motif (-184) and in PMA-treated cells this motif was bound with c-Jun as indicated from mobility shift assays. PMA up-regulated the c-Jun trans acting activity as indicated by the higher activity of a GAL4-regulated luciferase reporter in phorbol-ester-treated cells co-transfected with an expression vector encoding the c-Jun transactivation domain fused to the GAL4 DNA-binding domain. The ability of PMA to stimulate u-PAR promoter activity was effectively titrated out by the co-expression of either a kinase-defective JNK1 or a dominant negative MEKK1 the latter being an upstream activator of JNK1. Conversely, u-PAR promoter activity was stimulated by the co-expression of a constitutively active MEKK1 and this induction was antagonized by the inclusion of the kinase-defective JNK1 plasmid. We also determined the biological significance of the

  9. Urokinase-type Plasminogen Activator-like Proteases in Teleosts Lack Genuine Receptor-binding Epidermal Growth Factor-like Domains*

    PubMed Central

    Bager, René; Kristensen, Thomas K.; Jensen, Jan K.; Szczur, Agnieszka; Christensen, Anni; Andersen, Lisbeth M.; Johansen, Jesper S.; Larsen, Niels; Baatrup, Erik; Huang, Mingdong; Ploug, Michael; Andreasen, Peter A.

    2012-01-01

    Plasminogen activation catalyzed by urokinase-type plasminogen activator (uPA) plays an important role in normal and pathological tissue remodeling processes. Since its discovery in the mid-1980s, the cell membrane-anchored urokinase-type plasminogen activator receptor (uPAR) has been believed to be central to the functions of uPA, as uPA-catalyzed plasminogen activation activity appeared to be confined to cell surfaces through the binding of uPA to uPAR. However, a functional uPAR has so far only been identified in mammals. We have now cloned, recombinantly produced, and characterized two zebrafish proteases, zfuPA-a and zfuPA-b, which by several criteria are the fish orthologs of mammalian uPA. Thus, both proteases catalyze the activation of fish plasminogen efficiently and both proteases are inhibited rapidly by plasminogen activator inhibitor-1 (PAI-1). But zfuPA-a differs from mammalian uPA by lacking the exon encoding the uPAR-binding epidermal growth factor-like domain; zfuPA-b differs from mammalian uPA by lacking two cysteines of the epidermal growth factor-like domain and a uPAR-binding sequence comparable with that found in mammalian uPA. Accordingly, no zfuPA-b binding activity could be found in fish white blood cells or fish cell lines. We therefore propose that the current consensus of uPA-catalyzed plasminogen activation taking place on cell surfaces, derived from observations with mammals, is too narrow. Fish uPAs appear incapable of receptor binding in the manner known from mammals and uPA-catalyzed plasminogen activation in fish may occur mainly in solution. Studies with nonmammalian vertebrate species are needed to obtain a comprehensive understanding of the mechanism of plasminogen activation. PMID:22733817

  10. Mapping the topographic epitope landscape on the urokinase plasminogen activator receptor (uPAR) by surface plasmon resonance and X-ray crystallography.

    PubMed

    Zhao, Baoyu; Gandhi, Sonu; Yuan, Cai; Luo, Zhipu; Li, Rui; Gårdsvoll, Henrik; de Lorenzi, Valentina; Sidenius, Nicolai; Huang, Mingdong; Ploug, Michael

    2015-12-01

    The urokinase-type plasminogen activator receptor (uPAR or CD87) is a glycolipid-anchored membrane protein often expressed in the microenvironment of invasive solid cancers and high levels are generally associated with poor patient prognosis (Kriegbaum et al., 2011 [1]). uPAR is organized as a dynamic modular protein structure composed of three homologous Ly6/uPAR domains (LU).This internally flexible protein structure of uPAR enables an allosteric regulation of the interactions with its two principal ligands: the serine protease urokinase-type plasminogen activator (uPA) and the provisional matrix protein vitronectin (Vn) (Mertens et al., 2012; Gårdsvoll et al., 2011; Madsen et al., 2007 [2-4]). The data presented here relates to the non-covalent trapping of one of these biologically relevant uPAR-conformations by a novel class of monoclonal antibodies (Zhao et al., 2015 [5]) and to the general mapping of the topographic epitope landscape on uPAR. The methods required to achieve these data include: (1) recombinant expression and purification of a uPAR-hybrid protein trapped in the desired conformation [patent; WO 2013/020898 A12013]; (2) developing monoclonal antibodies with unique specificities using this protein as antigen; (3) mapping the functional epitope on uPAR for these mAbs by surface plasmon resonance with a complete library of purified single-site uPAR mutants (Zhao et al., 2015; Gårdsvoll et al., 2006 [5,6]); and finally (4) solving the three-dimensional structures for one of these mAbs by X-ray crystallography alone and in complex with uPAR [deposited in the PDB database as 4QTH and 4QTI, respectively]. PMID:26504891

  11. Breddin's graph for tectonic regimes

    NASA Astrophysics Data System (ADS)

    Célérier, Bernard; Séranne, Michel

    2001-05-01

    A simple graphical method is proposed to infer the tectonic regime from a fault and slip data set. An abacus is overlaid on a plot of the rake versus strike of the data. This yields the horizontal principal stress directions and a constraint on the stress tensor aspect ratio, in a manner similar to Breddin's graph for two-dimensional strain analysis. The main requirement is that one of the principal stress directions is close to the vertical. This method is illustrated on monophase synthetic and natural data, but is also expected to help sort out multiphase data sets.

  12. Ireland unveils new license regime

    SciTech Connect

    Not Available

    1992-11-23

    Ireland has unveiled new terns designed to integrate the licensing regime for oil and gas exploration and development. They apply to new exploration and development authorizations and replace the exclusive offshore licensing terns introduced in 1975. Holders of existing licenses are still subject to the 1975 terms but can choose the new terns under appropriate circumstances. Frontier exploration licenses are currently available to complement the standard and deepwater exploration licenses in use. Rental fees are now spread evenly over the duration of the license, thereby eliminating large upfront payments. Lease extensions also have been introduced to enable operators to judge commerciality of a discovery beyond the set license period.

  13. Different regimes of dynamic wetting

    NASA Astrophysics Data System (ADS)

    Gustav, Amberg; Wang, Jiayu; Do-Quang, Minh; Shiomi, Junichiro; Physiochemical fluid mechanics Team; Maruyama-Chiashi Laboratory Team

    2014-11-01

    Dynamic wetting, as observed when a droplet contacts a dry solid surface, is important in various engineering processes, such as printing, coating, and lubrication. Our overall aim is to investigate if and how the detailed properties of the solid surface influence the dynamics of wetting. Here we discuss how surface roughness influences the initial dynamic spreading of a partially wetting droplet by studying the spreading on a solid substrate patterned with microstructures just a few micrometers in size. This is complemented by matching numerical simulations. We present a parameter map, based on the properties of the liquid and the solid surface, which identifies qualitatively different spreading regimes, where the spreading speed is limited by either the liquid viscosity, the surface properties, or the liquid inertia. The peculiarities of the different spreading regimes are studied by detailed numerical simulations, in conjuction with experiments. This work was financially supported in part by, the Japan Society for the Promotion of Science (J.W. and J.S) and Swedish Governmental Agency for Innovation Systems (M.D.-Q. and G.A).

  14. Adaptation in Collaborative Governance Regimes

    NASA Astrophysics Data System (ADS)

    Emerson, Kirk; Gerlak, Andrea K.

    2014-10-01

    Adaptation and the adaptive capacity of human and environmental systems have been of central concern to natural and social science scholars, many of whom characterize and promote the need for collaborative cross-boundary systems that are seen as flexible and adaptive by definition. Researchers who study collaborative governance systems in the public administration, planning and policy literature have paid less attention to adaptive capacity specifically and institutional adaptation in general. This paper bridges the two literatures and finds four common dimensions of capacity, including structural arrangements, leadership, knowledge and learning, and resources. In this paper, we focus on institutional adaptation in the context of collaborative governance regimes and try to clarify and distinguish collaborative capacity from adaptive capacity and their contributions to adaptive action. We posit further that collaborative capacities generate associated adaptive capacities thereby enabling institutional adaptation within collaborative governance regimes. We develop these distinctions and linkages between collaborative and adaptive capacities with the help of an illustrative case study in watershed management within the National Estuary Program.

  15. A surfactant film spreading regime

    SciTech Connect

    Nikishov, V.I.

    1984-06-01

    Interest has recently increased in the study of the mechanisms whereby oil spills spread over sea and ocean surfaces. In the later stages of this process, when the petroleum film thickness becomes sufficiently small, the main forces determining the growth of its horizontal dimensions are surface tension and viscosity. In this case the flow characteristics do not depend on total quantity of spreading substance nor its surface concentration distribution. However, in the final stages of the spreading process the film becomes so thin that it is necessary to consider the effect of surface concentration distribution of the material on the process. Similar problems occur in the study of the spreading of a surfactant in the case where the total quantity of material is small and the surface tension regime sets in quickly. Therefore, the author examines here the spreading of a film in a regime wherein it is necessary to consider the total quantity of surfactant present, initially located on the surface of a viscous incompressible liquid.

  16. Adaptation in collaborative governance regimes.

    PubMed

    Emerson, Kirk; Gerlak, Andrea K

    2014-10-01

    Adaptation and the adaptive capacity of human and environmental systems have been of central concern to natural and social science scholars, many of whom characterize and promote the need for collaborative cross-boundary systems that are seen as flexible and adaptive by definition. Researchers who study collaborative governance systems in the public administration, planning and policy literature have paid less attention to adaptive capacity specifically and institutional adaptation in general. This paper bridges the two literatures and finds four common dimensions of capacity, including structural arrangements, leadership, knowledge and learning, and resources. In this paper, we focus on institutional adaptation in the context of collaborative governance regimes and try to clarify and distinguish collaborative capacity from adaptive capacity and their contributions to adaptive action. We posit further that collaborative capacities generate associated adaptive capacities thereby enabling institutional adaptation within collaborative governance regimes. We develop these distinctions and linkages between collaborative and adaptive capacities with the help of an illustrative case study in watershed management within the National Estuary Program. PMID:25073764

  17. Propagation Regime of Iron Dust Flames

    NASA Technical Reports Server (NTRS)

    Tang, Francois-David; Goroshin, Samuel; Higgins, Andrew J.

    2012-01-01

    A flame propagating through an iron-dust mixture can propagate in two asymptotic regimes. When the characteristic time of heat transfer between particles is much smaller than the characteristic time of particle combustion, the flame propagates in the continuum regime where the heat released by reacting particles can be modelled as a space-averaged function. In contrast, when the characteristic time of heat transfer is much larger than the particle reaction time, the flame can no longer be treated as a continuum due to dominating effects associated with the discrete nature of the particle reaction. The discrete regime is characterized by weak dependence of the flame speed on the oxygen concentration compared to the continuum regime. The discrete regime is observed in flames propagating through an iron dust cloud within a gas mixture containing xenon, while the continuum regime is obtained when xenon is substituted with helium.

  18. Discriminatory Proofreading Regimes in Nonequilibrium Systems

    NASA Astrophysics Data System (ADS)

    Murugan, Arvind; Huse, David A.; Leibler, Stanislas

    2014-04-01

    We use ideas from kinetic proofreading, an error-correcting mechanism in biology, to identify new kinetic regimes in nonequilibrium systems. These regimes are defined by the sensitivity of the occupancy of a state of the system to a change in its energy. In biological contexts, higher sensitivity corresponds to stronger discrimination between molecular substrates with different energetics competing in the same reaction. We study this discriminatory ability in systems with discrete states that are connected by a general network of transitions. We find multiple regimes of different discriminatory ability when the energy of a given state of the network is varied. Interestingly, the occupancy of the state can even increase with its energy, corresponding to an "antiproofreading" regime. The number and properties of such discriminatory regimes are limited by the topology of the network. Finally, we find that discriminatory regimes can be changed without modifying any "hard-wired" structural aspects of the system but rather by simply changing external chemical potentials.

  19. On unstable periodic regime of small HAWT

    NASA Astrophysics Data System (ADS)

    Dosaev, Marat Z.; Klimina, Liubov A.; Selyutskiy, Yury D.; Tsai, Mi-Ching; Yang, Hong-Tzer

    2012-11-01

    Dynamics of a small HAWT is studied. The closed mathematical model involving phenomenological description of both aerodynamic load upon turbine blades and permanent magnet electric generator is developed, in order to take into account the inductive reactance of the electric circuit. A series of experiments is performed in the subsonic wind tunnel of the LMSU Institute of Mechanics that allowed verifying the model and identifying its parameters. Parameters of dynamic model are identified, such as the coefficient of electromechanical interaction, the active internal resistance of generator, the circuit reactance. Parametric analysis of steady regimes is performed. The model prediction that HAWT operating dynamic system has two stable steady regimes (high speed regime and low speed one) is confirmed by experiments. Transient regimes are registered depending on parameters of the system, which allows estimating the unstable steady regime. The characteristics of the unstable regime are experimentally determined. Obtained results are used for estimation of aerodynamic moment acting on HAWT blades.

  20. Multistability of synchronous regimes in rotator ensembles.

    PubMed

    Kryukov, A K; Petrov, V S; Osipov, G V; Kurths, J

    2015-12-01

    We study collective dynamics in rotator ensembles and focus on the multistability of synchronous regimes in a chain of coupled rotators. We provide a detailed analysis of the number of coexisting regimes and estimate in particular, the synchronization boundary for different types of individual frequency distribution. The number of wave-based regimes coexisting for the same parameters and its dependence on the chain length are estimated. We give an analytical estimation for the synchronization frequency of the in-phase regime for a uniform individual frequency distribution. PMID:26723160

  1. Macromolecular interaction on a cAMP responsive region in the urokinase-type plasminogen activator gene: a role of protein phosphorylation.

    PubMed Central

    von der Ahe, D; Pearson, D; Nagamine, Y

    1990-01-01

    We have studied the regulation of urokinase-type plasminogen activator gene expression by cAMP in LLC-PK1 cells. We found a cAMP responsive region 3.4 kb upstream of the transcription initiation site, which comprised three protein-binding domains designated A, B, and C. Domains A and B both contain a sequence, TGACG, homologous to a consensus cAMP response element (CRE; TGACGTCA). Effective cAMP-mediated induction was achieved when these two domains were linked with domain C, which by itself did not confer cAMP responsiveness to a heterologous promoter nor contained CRE-like sequence, suggesting a functional cooperation among these domains. Results of competition studies using gel retardation and DNase I footprinting assays suggest that there is a protein-protein interaction between a CRE binding protein and a domain C binding protein. In gel retardation assays, binding of a nuclear protein to domains A and B was strongly augmented by addition of the catalytic subunit of cAMP-dependent protein kinase, whereas the protein binding to domain C was slightly inhibited, suggesting that protein phosphorylation is involved in the regulation of protein-DNA interaction. Images PMID:2159633

  2. The mRNA expression of soluble urokinase plasminogen activator surface receptor in human adipose tissue is positively correlated with body mass index.

    PubMed

    Ng, Hien Fuh; Chin, Kin Fah; Chan, Kok-Gan; Ngeow, Yun Fong

    2015-06-01

    suPLAUR is the transcript variant that encodes the soluble form of the urokinase plasminogen activator surface receptor (suPLAUR). This soluble protein has been shown to enhance leukocyte migration and adhesion, and its circulatory level is increased in inflammatory states. In this pilot study, we used RNA-Seq to examine the splicing pattern of PLAUR in omental adipose tissues from obese and lean individuals. Of the three transcript variants of the PLAUR gene, only the proportion of suPLAUR (transcript variant 2) increases in obesity. After removing the effects of gender and age, the expression of suPLAUR is positively correlated with body mass index. This observation was validated using RT-qPCR with an independent cohort of samples. Additionally, in our RNA-Seq differential expression analysis, we also observed, in obese adipose tissues, an up-regulation of genes encoding other proteins involved in the process of chemotaxis and leukocyte adhesion; of particular interest is the integrin beta 2 (ITGB2) that is known to interact with suPLAUR in leukocyte adhesion. These findings suggest an important role for suPLAUR in the recruitment of immune cells to obese adipose tissue, in the pathogenesis of obesity. PMID:26284904

  3. Incidence of Apoptosis in the Lymphoid Organs of Normal or Malaria Infected Mice is Decreased in CD18 and Urokinase - Receptor (UPAR, CD87) Deficient Mice

    PubMed Central

    da Laperrousaz, Chen; Vesin, Christian; Donati, Yves

    2001-01-01

    Incidence of apoptosis was investigated in the spleen and lymph nodes of +/+, CD18 -/- and urokinase receptor (uPAR, CD87) -/- mice, untreated or Plasmodium Berghei Anka (PbA) infected. In non infected mice, incidence of apoptosis was lower in the lymph nodes of CD18 -/- and uPAR -/- than in +/+ mice, as seen by FACS analysis to count the number of hypodiploid and Annexin-V binding cells. Infection of mice with PbA resulted in a marked increase in the size of spleen and lymph nodes 7–8 days after infection, which was slightly higher in uPAR -/- and CD18 -/- than in +/+ mice. PbA infection increased about 7 fold the incidence of apoptosis in the lymphoid organs of +/+, especially in the white pulp and germinal centers of the spleen and lymph nodes, while in contrast it was unchanged in PbA infected CD18 -/- or uPAR -/- mice. Serum IgG levels, and number of circulating leukocytes were significantly higher in both uPAR and CD18 -/- than in +/+ mice. These results indicate that the CD18 and uPAR surface molecules, which are known to be associated in the cell membrane, have an important influence upon the incidence of cell survival in both normal or stimulated lymphoid organs. PMID:11785668

  4. NFkappaB-dependent regulation of urokinase plasminogen activator by proanthocyanidin-rich grape seed extract: effect on invasion by prostate cancer cells.

    PubMed

    Uchino, Ryoji; Madhyastha, Radha; Madhyastha, Harishkumar; Dhungana, Sandra; Nakajima, Yuichi; Omura, Sayuri; Maruyama, Masugi

    2010-09-01

    Tumor invasion and metastasis present major obstacles to successful control of androgen-independent prostate cancer. Cell migration is a fundamental aspect of cancer cell metastasis. Urokinase plasminogen activator (uPA) system is implicated in cell migration and cancer metastasis and has potential to be developed as therapeutic target. In recent years, efficacy of dietary nutrients in preventing and curing cancer has gained increasing attention. One such promising candidate is proanthocyanidin-rich grape seed extract (GSE). We investigated the efficacy of GSE in regulating uPA expression and cell migration using highly metastatic androgen-independent PC3 prostate cancer cells as a model. GSE down-regulated uPA as a function of concentration. Additional studies showed that GSE inhibited DNA-binding activity of the transcription factor nuclear factor kappa B (NFkappaB), which in turn decreased NFkappaB-dependent uPA transcription. Invasion assays revealed the inhibitory effect of GSE on PC3 cell migration. These in-vitro experiments demonstrate the therapeutic property of GSE as an antimetastatic agent by targeting uPA. PMID:20502321

  5. Human single-chain urokinase is activated by the omptins PgtE of Salmonella enterica and Pla of Yersinia pestis despite mutations of active site residues.

    PubMed

    Järvinen, Hanna M; Laakkonen, Liisa; Haiko, Johanna; Johansson, Tiira; Juuti, Katri; Suomalainen, Marjo; Buchrieser, Carmen; Kalkkinen, Nisse; Korhonen, Timo K

    2013-08-01

    Fibrinolysis is important in cell migration and tightly regulated by specific inhibitors and activators; of the latter, urokinase (uPA) associates with enhancement of cell migration. Active uPA is formed through cleavage of the single-chain uPA (scuPA). The Salmonella enterica strain 14028R cleaved human scuPA at the peptide bond Lys158-Ile159, the site cleaved also by the physiological activator human plasmin. The cleavage led to activation of scuPA, while no cleavage or activation were detected with the mutant strain 14028R lacking the omptin protease PgtE. Complementation and expression studies confirmed the role of PgtE in scuPA activation. Similar cleavage and activation of scuPA were detected with recombinant Escherichia coli expressing the omptin genes pla from Yersinia pestis, ompT and ompP from E. coli, sopA from Shigella flexneri, and leo from Legionella pneumophila. For these omptins the activation of scuPA is the only shared function so far detected. Only poor cleavage and activation of scuPA were seen with YcoA of Y. pestis and YcoB of Yersinia pseudotuberculosis that are considered to be proteolytically inactive omptin variants. Point mutations of active site residues in Pla and PgtE had different effects on the proteolysis of plasminogen and of scuPA, indicating versatility in omptin proteolysis. PMID:23763588

  6. Hemangiosarcoma and its cancer stem cell subpopulation are effectively killed by a toxin targeted through epidermal growth factor and urokinase receptors.

    PubMed

    Schappa, Jill T; Frantz, Aric M; Gorden, Brandi H; Dickerson, Erin B; Vallera, Daniel A; Modiano, Jaime F

    2013-10-15

    Targeted toxins have the potential to overcome intrinsic or acquired resistance of cancer cells to conventional cytotoxic agents. Here, we hypothesized that EGFuPA-toxin, a bispecific ligand-targeted toxin (BLT) consisting of a deimmunized Pseudomonas exotoxin (PE) conjugated to epidermal growth factor and urokinase, would efficiently target and kill cells derived from canine hemangiosarcoma (HSA), a highly chemotherapy resistant tumor, as well as cultured hemangiospheres, used as a surrogate for cancer stem cells (CSC). EGFuPA-toxin showed cytotoxicity in four HSA cell lines (Emma, Frog, DD-1 and SB) at a concentration of ≤100 nM, and the cytotoxicity was dependent on specific ligand-receptor interactions. Monospecific targeted toxins also killed these chemoresistant cells; in this case, a "threshold" level of EGFR expression appeared to be required to make cells sensitive to the monospecific EGF-toxin, but not to the monospecific uPA-toxin. The IC₅₀ of CSCs was higher by approximately two orders of magnitude as compared to non-CSCs, but these cells were still sensitive to EGFuPA-toxin at nanomolar (i.e., pharmacologically relevant) concentrations, and when targeted by EGFuPA-toxin, resulted in death of the entire cell population. Taken together, our results support the use of these toxins to treat chemoresistant tumors such as sarcomas, including those that conform to the CSC model. Our results also support the use of companion animals with cancer for further translational development of these cytotoxic molecules. PMID:23553371

  7. The diagnostic value of soluble urokinase plasminogen activator receptor compared with C-reactive protein and procalcitonin in children with febrile neutropenia.

    PubMed

    Sirinoglu, Melis; Soysal, Ahmet; Karaaslan, Ayşe; Kepenekli Kadayifci, Eda; Cinel, Ismail; Koç, Ahmet; Tokuç, Gülnur; Yaman, Ali; Haklar, Goncagül; Şirikçi, Önder; Turan, Serap; Altınkanat Gelmez, Gülşen; Söyletir, Güner; Bakır, Mustafa

    2016-04-01

    The aim of the present study was to determine the diagnostic value of soluble urokinase plasminogen activator receptor (suPAR) in pediatric patients with febrile neutropenia. A prospective case-control study was performed. Patients included 29 children with febrile neutropenia (FN) and 27 control subjects without any infection or immunosuppressive condition. Blood samples were obtained on the day of admission and on the 4th to 7th days of the hospital stay. The median (minimum-maximum) serum levels of suPAR obtained on the first day of the admission were 2.08 (0.93-9.42) and 2.22 (1.08-5.13) ng/mL for the FN group and the control group, respectively. The median serum levels of suPAR in the FN and control groups were not significantly different (P = .053). The mean serum suPAR level was significantly higher in nonsurvivors than in survivors in the FN group (P < .05). In the FN group, the area under the receiver operating characteristics curve (AUCROC) for suPAR was 0.546, but no optimum cutoff value, sensitivity, specificity, negative predictive value (NPV), or positive predictive value (PPV) was obtained. We conclude that suPAR is not useful as a diagnostic biomarker in children with febrile neutropenia; however, persistent high serum suPAR level may predict mortality in FN in children. PMID:27057782

  8. Design of Specific Serine Protease Inhibitors Based on a Versatile Peptide Scaffold: Conversion of a Urokinase Inhibitor to a Plasma Kallikrein Inhibitor.

    PubMed

    Xu, Peng; Xu, Mingming; Jiang, Longguang; Yang, Qinglan; Luo, Zhipu; Dauter, Zbigniew; Huang, Mingdong; Andreasen, Peter A

    2015-11-25

    All serine proteases hydrolyze peptide bonds by the same basic mechanism and have very similar active sites, in spite of the fact that individual proteases have different physiological functions. We here report a strategy for designing high-affinity and high-specificity serine protease inhibitors using a versatile peptide scaffold, a 10-mer peptide, mupain-1 (CPAYSRYLDC). Mupain-1 was previously reported as a specific inhibitor of murine urokinase-type plasminogen activator (Ki = 0.55 μM) without measurable affinity to plasma kallikrein (Ki > 1000 μM). On the basis of a structure-based rational design, we substituted five residues of mupain-1 and converted it to a potent plasma kallikrein inhibitor (Ki = 0.014 μM). X-ray crystal structure analysis showed that the new peptide was able to adapt a new set of enzyme surface interactions by a slightly changed backbone conformation. Thus, with an appropriate re-engineering, mupain-1 can be redesigned to specific inhibitors of other serine proteases. PMID:26536069

  9. Discovery and SAR of Novel and Selective Inhibitors of Urokinase Plasminogen Activator (uPA) with an Imidazo[1,2-a]pyridine Scaffold.

    PubMed

    Gladysz, Rafaela; Adriaenssens, Yves; De Winter, Hans; Joossens, Jurgen; Lambeir, Anne-Marie; Augustyns, Koen; Van der Veken, Pieter

    2015-12-10

    Urokinase plasminogen activator (uPA) is a biomarker and therapeutic target for several cancer types. Its inhibition is regarded as a promising, noncytotoxic approach in cancer therapy by blocking growth and/or metastasis of solid tumors. Earlier, we reported the modified substrate activity screening (MSAS) approach and applied it for the identification of fragments with affinity for uPA's S1 pocket. Here, these fragments are transformed into a novel class of uPA inhibitors with an imidazo[1,2-a]pyridine scaffold. The SAR for uPA inhibition around this scaffold is explored, and the best compounds in the series have nanomolar uPA affinity and selectivity with respect to the related trypsin-like serine proteases (thrombin, tPA, FXa, plasmin, plasma kallikrein, trypsin, FVIIa). Finally, the approach followed for translating fragments into small molecules with a decorated scaffold architecture is conceptually straightforward and can be expected to be broadly applicable in fragment-based drug design. PMID:26575094

  10. Cytoskeletal reorganization and TPA differently modify AP-1 to induce the urokinase-type plasminogen activator gene in LLC-PK1 cells.

    PubMed Central

    Lee, J S; von der Ahe, D; Kiefer, B; Nagamine, Y

    1993-01-01

    Urokinase-type plasminogen activator (uPA) is an extracellular protease and expressed in various cells that exhibit dynamic changes in cell morphology, suggesting a link between cytoskeletal reorganization (CSR) and uPA expression. CSR can be induced by pharmacological agents, such as by colchicine for microtubule cytoskeleton and by cytochalasin for microfilament cytoskeleton. Using these agents, we previously showed that CSR induced the uPA gene in LLC-PK1 cells independently of the protein kinase C and cAMP-dependent protein kinase. Here we show that the induction of the uPA gene by CSR is mediated by the activation of c-Jun which interacts with an AP-1-like site located 2 kb upstream of the uPA gene. 12-O-tetradecanoylphorbol 13-acetate (TPA) induces the uPA gene through the same elements, but additionally utilizes an adjacent PEA3 element and induces c-fos. Furthermore, CSR induces a greater accumulation and a more pronounced phosphorylation of c-Jun than TPA induction. AP-1 is a positive regulator of growth and oncogenesis, and CSR is an integral part of these processes. Our results provide a view how CSR and AP-1 could be coupled in these processes. We also show that TPA and CSR act synergistically, suggesting a model where an initial activation signal could be amplified by CSR. Images PMID:8346015

  11. High Expression of Urokinase-Type Plasminogen Activator Is Associated with Lymph Node Metastasis of Invasive Ductal Carcinoma of the Breast

    PubMed Central

    Kim, Eun Young; Do, Sung-Im; Hyun, Keehoon; Park, Yong Lai; Kim, Dong-Hoon; Chae, Seoung Wan; Sohn, Jin Hee

    2016-01-01

    Purpose In the present study, we evaluated the levels of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor 1 (PAI-1) by performing immunohistochemical staining to determine whether they were reliable prognostic markers in patients with breast cancer. Methods Demographic and clinicopathological parameters of 214 patients with invasive ductal carcinoma (IDC) and 80 patients with ductal carcinoma in situ (DCIS) who were diagnosed and treated from 2006 to 2010 were analyzed. Tissue microarray was constructed and immunohistochemical staining was performed for each specimen. Results Univariate analyses showed that age at diagnosis, history of hormone replacement therapy, radiation therapy, skin and chest wall invasion, Paget disease, lymphovascular invasion, estrogen receptor positivity, and triple-negative subtype were significantly associated with patient prognosis (p<0.005). Patients with DCIS showed higher PAI-1 expression than patients with IDC (82.5% and 36.2%, respectively; p=0.012). Lymph node metastasis was more frequent in patients with high uPA levels than in patients with low uPA levels (p=0.001). Conclusion Our results suggested that PAI-1 was involved in tumor progression in the early stages of breast cancer, such as DCIS. In addition, our results suggested that high uPA levels were associated with the lymph node metastasis of IDC. PMID:27382391

  12. Urokinase-type Plasminogen Activator Resulting from Endometrial Carcinogenesis Enhances Tumor Invasion and Correlates with Poor Outcome of Endometrial Carcinoma Patients

    PubMed Central

    Huang, Chia-Yen; Chang, Ming-Cheng; Huang, Wei-Yun; Huang, Ching-Ting; Tang, Yu-Chien; Huang, Hsien-Da; Kuo, Kuan-Ting; Chen, Chi-An; Cheng, Wen-Fang

    2015-01-01

    The purpose of this study was to identify the dysregulated genes involved in the tumorigenesis and progression of endometrial endometrioid adenocarcinoma (EEC), and their possible mechanisms. Endometrial specimens including normal endometrial tissues, atypical endometrial hyperplasia, and EEC were analyzed. The expression profiles were compared using GeneChip Array. The gene expression levels were determined by real-time RT-PCR in the training and testing sets to correlate the clinico-pathological parameters of EEC. Immunoblotting, in vitro cell migration and invasion assays were performed in human endometrial cancer cell lines and their transfectants. In microarray analysis, seven dysregulated genes were identified. Only the levels of urokinase-type plasminogen activator (uPA) were higher in EEC with deep myometrial invasion, positive lympho-vascular space invasion, lymph node metastasis, and advanced stages. After multivariate analysis, uPA was the only independent poor prognostic factor for disease-free survival in the EEC patients (hazard ratio: 4.65, p = 0.03). uPA may enhance the migratory and invasive capabilities of endometrial tumor cells by the phosphorylation of ERK1/2, Akt and p38 molecules. uPA is a dysregulated gene involved in the tumorigenesis, bio-pathological features and outcomes of EEC. uPA may be a potential molecule and target for the detection and treatment of EEC. PMID:26033187

  13. Capacitance densitometer for flow regime identification

    DOEpatents

    Shipp, Jr., Roy L.

    1978-01-01

    This invention relates to a capacitance densitometer for determining the flow regime of a two-phase flow system. A two-element capacitance densitometer is used in conjunction with a conventional single-beam gamma densitometer to unambiguously identify the prevailing flow regime and the average density of a flowing fluid.

  14. Regimes of DNA confined in a nanochannel

    NASA Astrophysics Data System (ADS)

    Dai, Liang; Doyle, Patrick

    2014-03-01

    Scaling regimes for polymers confined to tubular channels are well established when the channel cross-sectional dimension is either very small (Odjik regime) or large (classic de Gennes regime) relative to the polymer Kuhn length. In the literature, there is no clear consensus regarding the intermediate region and if subregimes even exist to connect these two classic bounding regimes. The confluence of emerging single DNA mapping technologies and a resurged interest in the fundamental properties of confined polymers has led to extensive research in this area using DNA as a model system. Due to the DNA molecule's properties and limitations of nanofabrication, most experiments are performed in this intermediate regime with channel dimensions of a few Kuhn lengths. Here we use simulations and theory to reconcile conflicting theories and show that there are indeed extended de Gennes, partial alignment and hairpin regimes located between the two classic regimes. Simulations results for both chain extension and free energy support the existence of these regimes. This research was supported by the National Research Foundation Singapore through the Singapore MIT Alliance for Research and Technology's research program in BioSystems and Micromechanics, the National Science Foundation (CBET-1335938).

  15. FISHER INFORMATION AND ECOSYSTEM REGIME CHANGES

    EPA Science Inventory

    Following Fisher’s work, we propose two different expressions for the Fisher Information along with Shannon Information as a means of detecting and assessing shifts between alternative ecosystem regimes. Regime shifts are a consequence of bifurcations in the dynamics of an ecosys...

  16. Blowout regimes of plasma wakefield acceleration.

    PubMed

    Lotov, K V

    2004-04-01

    A wide region of beam parameters is numerically scanned and the dependence of wakefield properties on the beam length and current is clarified for the blowout regime of beam-plasma interaction. The main regimes of the plasma response are found, which qualitatively differ in the plasma behavior. To characterize the efficiency of the energy exchange between the beam and the plasma, the energy flux through the comoving window is introduced. Scalings of the energy flux for the linear plasma response and the main blowout regimes are studied. The most efficient energy transfer occurs in the so-called "strong beam" regime of interaction. For this regime, analytical approximations for various aspects of the plasma response are obtained. PMID:15169104

  17. Discrete fluorescent saturation regimes in multilevel systems

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.; Bhatia, A. K.

    1988-01-01

    Using models of multilevel atoms, the fluorescent process was examined for the ratio of the photooxidation rate, Pij, to the collisional oxidation rate, Cij, in the pumped resonance transition i-j. It is shown that, in the full range of the parameter Pij/Cij, there exist three distinct regimes (I, II, and III) which may be usefully exploited. These regimes are defined, respectively, by the following conditions: Pij/Cij smaller than about 1; Pij/Cij much greater than 1 and Pij much lower than Cki; and Pij/Cij much greater than 1 and Pij much higher than Cki, where Cki is the collisional rate populating the source level i. The only regime which is characterized by the sensitivity of fluorescent-fluorescent line intensity ratios to Pij is regime I. If regime III is reached, even fluorescent-nonfluorescent line ratios become independent of Pij. The analysis is applied to the resonant photoexcitation of a carbonlike ion.

  18. Snowpack regimes of the Western United States

    NASA Astrophysics Data System (ADS)

    Trujillo, Ernesto; Molotch, Noah P.

    2014-07-01

    Snow accumulation and melt patterns play a significant role in the water, energy, carbon, and nutrient cycles in the montane environments of the Western United States. Recent studies have illustrated that changes in the snow/rainfall apportionments and snow accumulation and melt patterns may occur as a consequence of changes in climate in the region. In order to understand how these changes may affect the snow regimes of the region, the current characteristics of the snow accumulation and melt patterns must be identified. Here we characterize the snow water equivalent (SWE) curve formed by the daily SWE values at 766 snow pillow stations in the Western United States, focusing on several metrics of the yearly SWE curves and the relationships between the different metrics. The metrics are the initial snow accumulation and snow disappearance dates, the peak snow accumulation and date of peak, the length of the snow accumulation season, the length of the snowmelt season, and the snow accumulation and snowmelt slopes. Three snow regimes emerge from these results: a maritime, an intermountain, and a continental regime. The maritime regime is characterized by higher maximum snow accumulations reaching 300 cm and shorter accumulation periods of less than 220 days. Conversely, the continental regime is characterized by lower maximum accumulations below 200 cm and longer accumulation periods reaching over 260 days. The intermountain regime lies in between. The regions that show the characteristics of the maritime regime include the Cascade Mountains, the Klamath Mountains, and the Sierra Nevada Mountains. The intermountain regime includes the Eastern Cascades slopes and foothills, the Blue Mountains, Northern and Central basins and ranges, the Columbia Mountains/Northern Rockies, the Idaho Batholith, and the Canadian Rockies. Lastly, the continental regime includes the Middle and Southern Rockies, and the Wasatch and Uinta Mountains. The implications of snow regime

  19. The Association between HbA1c, Fasting Glucose, 1-Hour Glucose and 2-Hour Glucose during an Oral Glucose Tolerance Test and Cardiovascular Disease in Individuals with Elevated Risk for Diabetes

    PubMed Central

    Lind, Marcus; Tuomilehto, Jaakko; Uusitupa, Matti; Nerman, Olle; Eriksson, Johan; Ilanne-Parikka, Pirjo; Keinänen-Kiukaanniemi, Sirkka; Peltonen, Markku; Pivodic, Aldina; Lindström, Jaana

    2014-01-01

    Objective To determine the association between HbA1c, fasting plasma glucose (FPG), 1-hour (1 hPG) and 2-hour (2 hPG) glucose after an oral glucose tolerance test (OGTT) and cardiovascular disease in individuals with elevated risk for diabetes. Design We studied the relationship between baseline, updated mean and updated (last) value of HbA1c, FPG, 1 hPG and 2 hPG after an oral 75 g glucose tolerance test (OGTT) and acute CVD events in 504 individuals with impaired glucose tolerance (IGT) at baseline enrolled in the Finnish Diabetes Prevention Study. Setting Follow-up of clinical trial. Participants 504 individuals with IGT were followed with yearly evaluations with OGTT, FPG and HbA1c. Main Outcome Measure Relative risk of CVD. Results Over a median follow-up of 9.0 years 34 (6.7%) participants had a CVD event, which increased to 52 (10.3%) over a median follow-up of 13.0 years when including events that occurred among participants following a diagnosis of diabetes. Updated mean HbA1c, 1 hPG and 2 hPG, HR per 1 unit SD of 1.57 (95% CI 1.16 to 2.11), p = 0.0032, 1.51 (1.03 to 2.23), p = 0.036 and 1.60 (1.10 to 2.34), p = 0.014, respectively, but not FPG (p = 0.11), were related to CVD. In analyses of the last value prior to the CVD event the same three glycaemic measurements were associated with the CVD events, with HRs per 1 unit SD of 1.45 (1.06 to 1.98), p = 0.020, 1.55 (1.04 to 2.29), p = 0.030 and 2.19 (1.51 to 3.18), p<0.0001, respectively but only 2 hPG remained significant in pairwise comparisons. Including the follow-up period after diabetes onset updated 2 hPG (p = 0.003) but not updated mean HbA1c (p = 0.08) was related to CVD. Conclusions and Relevance Current 2 hPG level in people with IGT is associated with increased risk of CVD. This supports its use in screening for prediabetes and monitoring glycaemic levels of people with prediabetes. PMID:25285769

  20. Abrupt climate-independent fire regime changes

    USGS Publications Warehouse

    Pausas, Juli G.; Keeley, Jon E.

    2014-01-01

    Wildfires have played a determining role in distribution, composition and structure of many ecosystems worldwide and climatic changes are widely considered to be a major driver of future fire regime changes. However, forecasting future climatic change induced impacts on fire regimes will require a clearer understanding of other drivers of abrupt fire regime changes. Here, we focus on evidence from different environmental and temporal settings of fire regimes changes that are not directly attributed to climatic changes. We review key cases of these abrupt fire regime changes at different spatial and temporal scales, including those directly driven (i) by fauna, (ii) by invasive plant species, and (iii) by socio-economic and policy changes. All these drivers might generate non-linear effects of landscape changes in fuel structure; that is, they generate fuel changes that can cross thresholds of landscape continuity, and thus drastically change fire activity. Although climatic changes might contribute to some of these changes, there are also many instances that are not primarily linked to climatic shifts. Understanding the mechanism driving fire regime changes should contribute to our ability to better assess future fire regimes.

  1. Phospho-MEK1/2 and uPAR Expression Determine Sensitivity of AML Blasts to a Urokinase-Activated Anthrax Lethal Toxin (PrAgU2/LF)1

    PubMed Central

    Bekdash, Amira; Darwish, Manal; Timsah, Zahra; Kassab, Elias; Ghanem, Hadi; Najjar, Vicky; Ghosn, Marwan; Nasser, Selim; El-Hajj, Hiba; Bazerbachi, Ali; Liu, Shihui; Leppla, Stephen H.; Frankel, Arthur E.; Abi-Habib, Ralph J.

    2015-01-01

    In this study, we attempt to target both the urokinase plasminogen activator and the mitogen-activated protein kinase pathway in acute myeloid leukemia (AML) cell lines and primary AML blasts using PrAgU2/LF, a urokinase-activated anthrax lethal toxin. PrAgU2/LF was cytotoxic to five out of nine AML cell lines. Cytotoxicity of PrAgU2/LF appeared to be nonapoptotic and was associated with MAPK activation and urokinase activity because all the PrAgU2/LF-sensitive cell lines showed both uPAR expression and high levels of MEK1/2 phosphorylation. Inhibition of uPAR or desensitization of cells to MEK1/2 inhibition blocked toxicity of PrAgU2/LF, indicating requirement for both uPAR expression and MAPK activation for activity. PrAgU2/LF was also cytotoxic to primary blasts from AML patients, with blasts from four out of five patients showing a cytotoxic response to PrAgU2/LF. Cytotoxicity of primary AML blasts was also dependent on uPAR expression and phos-MEK1/2 levels. CD34+ bone marrow blasts and peripheral blood mononuclear cells lacked uPAR expression and were resistant to PrAgU2/LF, demonstrating the lack of toxicity to normal hematological cells and, therefore, the tumor selectivity of this approach. Dose escalation in mice revealed that the maximal tolerated dose of PrAgU2/LF is at least 5.7-fold higher than that of the wild-type anthrax lethal toxin, PrAg/LF, further demonstrating the increased safety of this molecule. We have shown, in this study, that PrAgU2/LF is a novel, dual-specific molecule for the selective targeting of AML. PMID:26500025

  2. Earth Regime Network Evolution Study (ERNESt)

    NASA Technical Reports Server (NTRS)

    Menrad, Bob

    2016-01-01

    Speaker and Presenter at the Lincoln Laboratory Communications Workshop on April 5, 2016 at the Massachusetts Institute of Technology Lincoln Laboratory in Lexington, MA. A visual presentation titled Earth Regimes Network Evolution Study (ERNESt).

  3. Electron transport fluxes in potato plateau regime

    SciTech Connect

    Shaing, K.C.; Hazeltine, R.D.

    1997-12-01

    Electron transport fluxes in the potato plateau regime are calculated from the solutions of the drift kinetic equation and fluid equations. It is found that the bootstrap current density remains finite in the region close to the magnetic axis, although it decreases with increasing collision frequency. This finite amount of the bootstrap current in the relatively collisional regime is important in modeling tokamak startup with 100{percent} bootstrap current. {copyright} {ital 1997 American Institute of Physics.}

  4. Molecular motors in conservative and dissipative regimes

    NASA Astrophysics Data System (ADS)

    Perez-Carrasco, R.; Sancho, J. M.

    2011-10-01

    We present a theoretical study of a rotatory molecular motor under a conservative torque regime. We show that conservative and dissipative regimes present a different observable phenomenology. Our approach starts with a preliminary deterministic calculation of the motor cycle, which is complemented with stochastic simulations of a Langevin equation under a flashing ratchet potential. Finally, by using parameter values obtained from independent experimental information, our theoretical predictions are compared with experimental data of the F1-ATPase motor of the Bacillus PS3.

  5. Regime Diagrams for K-Theory Dispersion

    NASA Astrophysics Data System (ADS)

    Smith, Ronald B.

    2011-06-01

    In atmospheric dispersion, the "non-Gaussian" effects of gravitational settling, the vertical gradient in diffusivity and the surface deposition do not enter uniformly but rather break up parameter space into several discrete regimes. Here, we describe regime diagrams that are constructed for K-theory dispersion of effluent from a surface line source in unsheared inhomogeneous turbulence, using a previously derived Fourier-Hankel method. This K-theory formulation differs from the traditional one by keeping a non-zero diffusivity at the ground. This change allows for turbulent exchange between the canopy and the atmosphere and allows new natural length scales to emerge. The axes on the regime diagrams are non-dimensional distance defined as the ratio of downwind distance to the characteristic length scale for each effect. For each value of the ratio of settling speed to the K gradient, two to four regimes are found. Concentration formulae are given for each regime. The regime diagrams allow real dispersion problems to be categorized and the validity of end-state concentration formulae to be judged.

  6. Soluble Urokinase Receptor Levels Are Correlated with Focal Segmental Glomerulosclerosis Lesions in IgA Nephropathy: A Cohort Study from China

    PubMed Central

    Guo, Shui-Ming; Han, Min; Chen, Mei-Xue; Ning, Yong; Pei, Guang-Chang; Li, Yue-Qiang; Dai, Wei; Ge, Shu-Wang; Deng, Yuan-Jun; Guo, Yan-Yan; Li, Xiao-Qing; Haller, Hermann; Xu, Gang; Rong, Song

    2015-01-01

    Background Soluble urokinase receptor (suPAR) may be involved in the pathological mechanisms of focal segmental glomerulosclerosis (FSGS) changes. However, it remains unclear whether suPAR is correlated with the FSGS-like lesions in IgA nephropathy (IgAN). Methods We measured the plasma suPAR levels in 138 patients with IgAN, and then their clinical and pathological relationships were analyzed. Results We found that the plasma suPAR levels were significantly correlated with age and renal function by both univariate and multivariate analysis in our IgAN patient cohort. Female had higher plasma suPAR levels and no significant correlation was observed between plasma suPAR levels and 24-h urine protein and highly sensitive C-reaction protein with multivariate analysis. In our cohort, sixty of these IgAN patients could be diagnosed with a type of FSGS lesions. The plasma suPAR levels were higher in the IgAN patients with FSGS lesions than in the IgAN patients without FSGS lesions by univariate (P < 0.0001) and multivariate (P < 0.001) analysis adjusting for other predictor variables, which might be helpful to differentiate the pathological changes with and without FSGS lesions. And the optimal cutoff value was 1806 pg/ml in this study. The plasma suPAR concentrations were also associated with the degree of tubular atrophy/interstitial fibrosis in both univariate and multivariate analysis. In multivariate analysis, the plasma suPAR levels were correlated with the percentage of crescents, not global sclerosis and arterial lesions. Conclusions Our study suggested that the plasma suPAR levels were associated with age, gender, renal function, the degree of tubular atrophy/interstitial fibrosis and the percentage of crescent formation. The plasma suPAR might be a potential predictor for the presence of FSGS pathological lesions in Chinese patients with IgAN. PMID:26380984

  7. Aberrant glomerular filtration of urokinase-type plasminogen activator in nephrotic syndrome leads to amiloride-sensitive plasminogen activation in urine.

    PubMed

    Stæhr, Mette; Buhl, Kristian B; Andersen, René F; Svenningsen, Per; Nielsen, Flemming; Hinrichs, Gitte Rye; Bistrup, Claus; Jensen, Boye L

    2015-08-01

    In nephrotic syndrome, aberrant glomerular filtration of plasminogen and conversion to active plasmin in preurine are thought to activate proteolytically epithelial sodium channel (ENaC) and contribute to sodium retention and edema. The ENaC blocker amiloride is an off-target inhibitor of urokinase-type plasminogen activator (uPA) in vitro. It was hypothesized that uPA is abnormally filtered to preurine and is inhibited in urine by amiloride in nephrotic syndrome. This was tested by determination of Na(+) balance, uPA protein and activity, and amiloride concentration in urine from rats with puromycin aminonucleoside (PAN)-induced nephrotic syndrome. Urine samples from 6 adult and 18 pediatric patients with nephrotic syndrome were analyzed for uPA activity and protein. PAN treatment induced significant proteinuria in rats which coincided with increased urine uPA protein and activity, increased urine protease activity, and total plasminogen/plasmin concentration and Na(+) retention. Amiloride (2 mg·kg(-1)·24 h(-1)) concentration in urine was in the range 10-20 μmol/l and reduced significantly urine uPA activity, plasminogen activation, protease activity, and sodium retention in PAN rats, while proteinuria was not altered. In paired urine samples, uPA protein was significantly elevated in urine from children with active nephrotic syndrome compared with remission phase. In six adult nephrotic patients, urine uPA protein and activity correlated positively with 24 h urine protein excretion. In conclusion, nephrotic syndrome is associated with aberrant filtration of uPA across the injured glomerular barrier. Amiloride inhibits urine uPA activity which attenuates plasminogen activation and urine protease activity in vivo. Urine uPA is a relevant target for amiloride in vivo. PMID:25972510

  8. Characterization of the interaction between heterodimeric αvβ6 integrin and urokinase plasminogen activator receptor (uPAR) using functional proteomics.

    PubMed

    Ahn, Seong Beom; Mohamedali, Abidali; Anand, Samyuktha; Cheruku, Harish R; Birch, Debra; Sowmya, Gopichandran; Cantor, David; Ranganathan, Shoba; Inglis, David W; Frank, Ronald; Agrez, Michael; Nice, Edouard C; Baker, Mark S

    2014-12-01

    Urokinase plasminogen activator receptor (uPAR) and the epithelial integrin αvβ6 are thought to individually play critical roles in cancer metastasis. These observations have been highlighted by the recent discovery (by proteomics) of an interaction between these two molecules, which are also both implicated in the epithelial-mesenchymal transition (EMT) that facilitates escape of cells from tissue barriers and is a common signature of cancer metastases. In this study, orthogonal in cellulo and in vitro functional proteomic approaches were used to better characterize the uPAR·αvβ6 interaction. Proximity ligation assays (PLA) confirmed the uPAR·αvβ6 interaction on OVCA429 (ovarian cancer line) and four different colon cancer cell lines including positive controls in cells with de novo β6 subunit expression. PLA studies were then validated using peptide arrays, which also identified potential physical sites of uPAR interaction with αvβ6, as well as verifying interactions with other known uPAR ligands (e.g., uPA, vitronectin) and individual integrin subunits (i.e., αv, β1, β3, and β6 alone). Our data suggest that interaction with uPAR requires expression of the complete αβ heterodimer (e.g., αvβ6), not individual subunits (i.e., αv, β1, β3, or β6). Finally, using in silico structural analyses in concert with these functional proteomics studies, we propose and demonstrate that the most likely unique sites of interaction between αvβ6 and uPAR are located in uPAR domains II and III. PMID:25318615

  9. Cyclization of the urokinase receptor-derived ser-arg-ser-arg-tyr Peptide generates a potent inhibitor of trans-endothelial migration of monocytes.

    PubMed

    Yousif, Ali Munaim; Minopoli, Michele; Bifulco, Katia; Ingangi, Vincenzo; Di Carluccio, Gioconda; Merlino, Francesco; Motti, Maria Letizia; Grieco, Paolo; Carriero, Maria Vincenza

    2015-01-01

    The receptor for the urokinase-type plasminogen activator (uPAR) is a widely recognized master regulator of cell migration and uPAR88-92 is the minimal sequence required to induce cell motility. We and others have previously documented that the uPAR88-92 sequence, even in the form of synthetic linear peptide (SRSRY), interacts with the formyl peptide receptor type 1 (FPR1), henceforth inducing cell migration of several cell lines, including monocytes. FPR1 is mainly expressed by mammalian phagocytic leukocytes and plays a crucial role in chemotaxis. In this study, we present evidence that the cyclization of the SRSRY sequence generates a new potent and stable inhibitor of monocyte trafficking. In rat basophilic leukaemia RBL-2H3/ETFR cells expressing high levels of constitutively activated FPR1, the cyclic SRSRY peptide ([SRSRY]) blocks FPR1 mediated cell migration by interfering with both internalization and ligand-uptake of FPR1. Similarly to RBL-2H3/ETFR cells, [SRSRY] competes with fMLF for binding to FPR1 and prevents agonist-induced FPR1 internalization in human monocyte THP-1 cells. Unlike scramble [RSSYR], [SRSRY] inhibits fMLF-directed migration of monocytes in a dose-dependent manner, with IC50 value of 0.01 nM. PMA-differentiated THP-1 cell exposure to fMLF gradient causes a marked cytoskeletal re-organization with the formation of F-actin rich pseudopodia that are prevented by the addition of [SRSRY]. Furthermore, [SRSRY] prevents migration of human primary monocytes and trans-endothelial migration of monocytes. Our findings indicate that [SRSRY] is a new FPR1 inhibitor which may suggest the development of new drugs for treating pathological conditions sustained by increased motility of monocytes, such as chronic inflammatory diseases. PMID:25938482

  10. Cyclization of the Urokinase Receptor-Derived Ser-Arg-Ser-Arg-Tyr Peptide Generates a Potent Inhibitor of Trans-Endothelial Migration of Monocytes

    PubMed Central

    Bifulco, Katia; Ingangi, Vincenzo; Di Carluccio, Gioconda; Merlino, Francesco; Motti, Maria Letizia; Grieco, Paolo; Carriero, Maria Vincenza

    2015-01-01

    The receptor for the urokinase-type plasminogen activator (uPAR) is a widely recognized master regulator of cell migration and uPAR88-92 is the minimal sequence required to induce cell motility. We and others have previously documented that the uPAR88-92 sequence, even in the form of synthetic linear peptide (SRSRY), interacts with the formyl peptide receptor type 1 (FPR1), henceforth inducing cell migration of several cell lines, including monocytes. FPR1 is mainly expressed by mammalian phagocytic leukocytes and plays a crucial role in chemotaxis. In this study, we present evidence that the cyclization of the SRSRY sequence generates a new potent and stable inhibitor of monocyte trafficking. In rat basophilic leukaemia RBL-2H3/ETFR cells expressing high levels of constitutively activated FPR1, the cyclic SRSRY peptide ([SRSRY]) blocks FPR1 mediated cell migration by interfering with both internalization and ligand-uptake of FPR1. Similarly to RBL-2H3/ETFR cells, [SRSRY] competes with fMLF for binding to FPR1 and prevents agonist-induced FPR1 internalization in human monocyte THP-1 cells. Unlike scramble [RSSYR], [SRSRY] inhibits fMLF-directed migration of monocytes in a dose-dependent manner, with IC50 value of 0.01 nM. PMA-differentiated THP-1 cell exposure to fMLF gradient causes a marked cytoskeletal re-organization with the formation of F-actin rich pseudopodia that are prevented by the addition of [SRSRY]. Furthermore, [SRSRY] prevents migration of human primary monocytes and trans-endothelial migration of monocytes. Our findings indicate that [SRSRY] is a new FPR1 inhibitor which may suggest the development of new drugs for treating pathological conditions sustained by increased motility of monocytes, such as chronic inflammatory diseases. PMID:25938482

  11. The receptor for urokinase-plasminogen activator (uPAR) controls plasticity of cancer cell movement in mesenchymal and amoeboid migration style.

    PubMed

    Margheri, Francesca; Luciani, Cristina; Taddei, Maria Letizia; Giannoni, Elisa; Laurenzana, Anna; Biagioni, Alessio; Chillà, Anastasia; Chiarugi, Paola; Fibbi, Gabriella; Del Rosso, Mario

    2014-03-30

    The receptor for the urokinase plasminogen activator (uPAR) is up-regulated in malignant tumors. Historically the function of uPAR in cancer cell invasion is strictly related to its property to promote uPA-dependent proteolysis of extracellular matrix and to open a path to malignant cells. These features are typical of mesenchymal motility. Here we show that the full-length form of uPAR is required when prostate and melanoma cancer cells convert their migration style from the "path generating" mesenchymal to the "path finding" amoeboid one, thus conferring a plasticity to tumor cell invasiveness across three-dimensional matrices. Indeed, in response to a protease inhibitors-rich milieu, prostate and melanoma cells activated an amoeboid invasion program connoted by retraction of cell protrusions, RhoA-mediated rounding of the cell body, formation of a cortical ring of actin and a reduction of Rac-1 activation. While the mesenchymal movement was reduced upon silencing of uPAR expression, the amoeboid one was almost completely abolished, in parallel with a deregulation of small Rho-GTPases activity. In melanoma and prostate cancer cells we have shown uPAR colocalization with β1/β3 integrins and actin cytoskeleton, as well integrins-actin co-localization under both mesenchymal and amoeboid conditions. Such co-localizations were lost upon treatment of cells with a peptide that inhibits uPAR-integrin interactions. Similarly to uPAR silencing, the peptide reduced mesenchymal invasion and almost abolished the amoeboid one. These results indicate that full-length uPAR bridges the mesenchymal and amoeboid style of movement by an inward-oriented activity based on its property to promote integrin-actin interactions and the following cytoskeleton assembly. PMID:24681666

  12. Modulation of Cellular Migration and Survival by c-Myc through the Downregulation of Urokinase (uPA) and uPA Receptor▿ †

    PubMed Central

    Alfano, Daniela; Votta, Giuseppina; Schulze, Almut; Downward, Julian; Caputi, Mario; Stoppelli, Maria Patrizia; Iaccarino, Ingram

    2010-01-01

    It has been proposed that c-Myc proapoptotic activity accounts for most of its restraint of tumor formation. We established a telomerase-immortalized human epithelial cell line expressing an activatable c-Myc protein. We found that c-Myc activation induces, in addition to increased sensitivity to apoptosis, reductions in cell motility and invasiveness. Transcriptome analysis revealed that urokinase (uPA) and uPA receptor (uPAR) were strongly downregulated by c-Myc. Evidence is provided that the repression of uPA and uPAR may account for most of the antimigratory and proapoptotic activities of c-Myc. c-Myc is known to cooperate with Ras in cellular transformation. We therefore investigated if this cooperation could converge in the control of uPA/uPAR expression. We found that Ras is able to block the effects of c-Myc activation on apoptosis and cellular motility but not on cell invasiveness. Accordingly, the activation of c-Myc in the context of Ras expression had only minor influence on uPAR expression but still had a profound repressive effect on uPA expression. Thus, the differential regulation of uPA and uPAR by c-Myc and Ras correlates with the effects of these two oncoproteins on cell motility, invasiveness, and survival. In conclusion, we have discovered a novel link between c-Myc and uPA/uPAR. We propose that reductions of cell motility and invasiveness could contribute to the inhibition of tumorigenesis by c-Myc and that the regulation of uPA and uPAR expression may be a component of the ability of c-Myc to reduce motility and invasiveness. PMID:20123981

  13. Epithelial and Stromal Cell Urokinase Plasminogen Activator Receptor Expression Differentially Correlates with Survival in Rectal Cancer Stages B and C Patients

    PubMed Central

    Ahn, Seong Beom; Chan, Charles; Dent, Owen F.; Mohamedali, Abidali; Kwun, Sun Young; Clarke, Candice; Fletcher, Julie; Chapuis, Pierre H.; Nice, Edouard C.; Baker, Mark S.

    2015-01-01

    Urokinase plasminogen activator receptor (uPAR) has been proposed as a potential prognostic factor for colorectal cancer (CRC) patient survival. However, CRC uPAR expression remains controversial, especially regarding cell types where uPAR is overexpressed (e.g., epithelium (uPARE) or stroma-associated cells (uPARS)) and associated prognostic relevance. In this study, two epitope-specific anti-uPAR monoclonal antibodies (MAbs) could discriminate expression of uPARE from uPARS and were used to examine this association with survival of stages B and C rectal cancer (RC) patients. Using immunohistochemistry, MAbs #3937 and R4 were used to discriminate uPARE from uPARS respectively in the central and invasive frontal regions of 170 stage B and 179 stage C RC specimens. Kaplan-Meier and Cox regression analyses were used to determine association with survival. uPAR expression occurred in both epithelial and stromal compartments with differential expression observed in many cases, indicating uPARE and uPARS have different cellular roles. In the central and invasive frontal regions, uPARE was adversely associated with overall stage B survival (HR = 1.9; p = 0.014 and HR = 1.5; p = 0.031, respectively) reproducing results from previous studies. uPARS at the invasive front was associated with longer stage C survival (HR = 0.6; p = 0.007), reflecting studies demonstrating that macrophage peritumoural accumulation is associated with longer survival. This study demonstrates that different uPAR epitopes should be considered as being expressed on different cell types during tumour progression and at different stages in RC. Understanding how uPARE and uPARS expression affects survival is anticipated to be a useful clinical prognostic marker of stages B and C RC. PMID:25692297

  14. Soluble Urokinase Receptor Is Released Selectively by Glioblastoma Cells That Express Epidermal Growth Factor Receptor Variant III and Promotes Tumor Cell Migration and Invasion*♦

    PubMed Central

    Gilder, Andrew S.; Jones, Karra A.; Hu, Jingjing; Wang, Lei; Chen, Clark C.; Carter, Bob S.; Gonias, Steven L.

    2015-01-01

    Genomic heterogeneity is characteristic of glioblastoma (GBM). In many GBMs, the EGF receptor gene (EGFR) is amplified and may be truncated to generate a constitutively active form of the receptor called EGFRvIII. EGFR gene amplification and EGFRvIII are associated with GBM progression, even when only a small fraction of the tumor cells express EGFRvIII. In this study, we show that EGFRvIII-positive GBM cells express significantly increased levels of cellular urokinase receptor (uPAR) and release increased amounts of soluble uPAR (suPAR). When mice were xenografted with human EGFRvIII-expressing GBM cells, tumor-derived suPAR was detected in the plasma, and the level was significantly increased compared with that detected in plasma samples from control mice xenografted with EGFRvIII-negative GBM cells. suPAR also was increased in plasma from patients with EGFRvIII-positive GBMs. Purified suPAR was biologically active when added to cultures of EGFRvIII-negative GBM cells, activating cell signaling and promoting cell migration and invasion. suPAR did not significantly stimulate cell signaling or migration of EGFRvIII-positive cells, probably because cell signaling was already substantially activated in these cells. The activities of suPAR were replicated by conditioned medium (CM) from EGFRvIII-positive GBM cells. When the CM was preincubated with uPAR-neutralizing antibody or when uPAR gene expression was silenced in cells used to prepare CM, the activity of the CM was significantly attenuated. These results suggest that suPAR may function as an important paracrine signaling factor in EGFRvIII-positive GBMs, inducing an aggressive phenotype in tumor cells that are EGFRvIII-negative. PMID:25837250

  15. Protease Nexin-1 affects the migration and invasion of C6 glioma cells through the regulation of urokinase Plasminogen Activator and Matrix Metalloproteinase-9/2.

    PubMed

    Pagliara, Valentina; Adornetto, Annagrazia; Mammì, Maria; Masullo, Mariorosario; Sarnataro, Daniela; Pietropaolo, Concetta; Arcone, Rosaria

    2014-11-01

    Protease Nexin-1 (PN-1) or Serpine2 is a physiological regulator of extracellular proteases as thrombin and urokinase (uPA) in the brain. Besides, PN-1 is also implicated in some human cancers and further identified as a substrate for Matrix Metalloproteinase (MMP)-9, a key enzyme in tumor invasiveness. Our aim was to study the role of PN-1 in the migration and invasive potential of glioma cells, using the rat C6 glioma cell line as stable clones transfected with pAVU6+27 vector expressing PN-1 short-hairpin RNA. We find that PN-1 knockdown enhanced the in vitro migration and invasiveness of C6 cells which also showed a strong gelatinolytic activity by in situ zymography. PN-1 silencing did not alter prothrombin whereas increased uPA, MMP-9 and MMP-2 expression levels and gelatinolytic activity in a conditioned medium from stable C6 cells. Selective inhibitors for MMP-9 (Inhibitor I), MMP-2 (Inhibitor III) or exogenous recombinant PN-1 added to the culture medium of C6 silenced cells restored either the migration and invasive ability or gelatinolytic activity thus validating the specificity of PN-1 silencing strategy. Phosphorylation levels of extracellular signal-related kinases (Erk1/2 and p38 MAPK) involved in MMP-9 and MMP-2 signaling were increased in PN-1 silenced cells. This study shows that PN-1 affects glioma cell migration and invasiveness through the regulation of uPA and MMP-9/2 expression levels which contribute to the degradation of extracellular matrix during tumor invasion. PMID:25072751

  16. The receptor for urokinase-plasminogen activator (uPAR) controls plasticity of cancer cell movement in mesenchymal and amoeboid migration style

    PubMed Central

    Taddei, Maria Letizia; Giannoni, Elisa; Laurenzana, Anna; Biagioni, Alessio; Chillà, Anastasia; Chiarugi, Paola; Fibbi, Gabriella; Rosso1, Mario Del

    2014-01-01

    The receptor for the urokinase plasminogen activator (uPAR) is up-regulated in malignant tumors. Historically the function of uPAR in cancer cell invasion is strictly related to its property to promote uPA-dependent proteolysis of extracellular matrix and to open a path to malignant cells. These features are typical of mesenchymal motility. Here we show that the full-length form of uPAR is required when prostate and melanoma cancer cells convert their migration style from the “path generating” mesenchymal to the “path finding” amoeboid one, thus conferring a plasticity to tumor cell invasiveness across three-dimensional matrices. Indeed, in response to a protease inhibitors-rich milieu, prostate and melanoma cells activated an amoeboid invasion program connoted by retraction of cell protrusions, RhoA-mediated rounding of the cell body, formation of a cortical ring of actin and a reduction of Rac-1 activation. While the mesenchymal movement was reduced upon silencing of uPAR expression, the amoeboid one was almost completely abolished, in parallel with a deregulation of small Rho-GTPases activity. In melanoma and prostate cancer cells we have shown uPAR colocalization with β1/β3 integrins and actin cytoskeleton, as well integrins-actin co-localization under both mesenchymal and amoeboid conditions. Such co-localizations were lost upon treatment of cells with a peptide that inhibits uPAR-integrin interactions. Similarly to uPAR silencing, the peptide reduced mesenchymal invasion and almost abolished the amoeboid one. These results indicate that full-length uPAR bridges the mesenchymal and amoeboid style of movement by an inward-oriented activity based on its property to promote integrin-actin interactions and the following cytoskeleton assembly. PMID:24681666

  17. Elevated urinary levels of urokinase-type plasminogen activator receptor (uPAR) in pancreatic ductal adenocarcinoma identify a clinically high-risk group

    PubMed Central

    2011-01-01

    Background The urokinase plasminogen activator receptor is highly expressed and its gene is amplified in about 50% of pancreatic ductal adenocarcinomas; this last feature is associated with worse prognosis. It is unknown whether the level of its soluble form (suPAR) in urine may be a diagnostic-prognostic marker in these patients. Methods The urinary level of suPAR was measured in 146 patients, 94 pancreatic ductal adenocarcinoma and 52 chronic pancreatitis. Urine from 104 healthy subjects with similar age and gender distribution served as controls. suPAR levels were normalized with creatinine levels (suPAR/creatinine, ng/mg) to remove urine dilution effect. Results Urinary suPAR/creatinine values of pancreatic ductal adenocarcinoma patients were significantly higher (median 9.8; 25th-75th percentiles 5.3-20.7) than those of either healthy donors (median 0; 0-0.5) or chronic pancreatitis patients (median 2.7; 0.9-4.7). The distribution of values among cancer patients was widespread and asymmetric, 53% subjects having values beyond the 95th percentile of healthy donors. The values of suPAR/creatinine did not correlate with tumour stage, Ca19-9 or CEA levels. Higher values correlated with poor prognosis among non-resected patients at univariate analysis; multivariate Cox regression identified high urinary suPAR/creatinine as an independent predictor of poor survival among all cancer patients (odds ratio 2.10, p = 0.0023), together with tumour stage (stage III odds ratio 2.65, p = 0.0017; stage IV odds ratio 4.61, p < 0.0001) and female gender (odds ratio 1.85, p = 0.01). Conclusions A high urinary suPAR/creatinine ratio represents a useful marker for the identification of a subset of patients with poorer outcome. PMID:21999221

  18. A holistic view of marine regime shifts

    PubMed Central

    Conversi, Alessandra; Dakos, Vasilis; Gårdmark, Anna; Ling, Scott; Folke, Carl; Mumby, Peter J.; Greene, Charles; Edwards, Martin; Blenckner, Thorsten; Casini, Michele; Pershing, Andrew; Möllmann, Christian

    2015-01-01

    Understanding marine regime shifts is important not only for ecology but also for developing marine management that assures the provision of ecosystem services to humanity. While regime shift theory is well developed, there is still no common understanding on drivers, mechanisms and characteristic of abrupt changes in real marine ecosystems. Based on contributions to the present theme issue, we highlight some general issues that need to be overcome for developing a more comprehensive understanding of marine ecosystem regime shifts. We find a great divide between benthic reef and pelagic ocean systems in how regime shift theory is linked to observed abrupt changes. Furthermore, we suggest that the long-lasting discussion on the prevalence of top-down trophic or bottom-up physical drivers in inducing regime shifts may be overcome by taking into consideration the synergistic interactions of multiple stressors, and the special characteristics of different ecosystem types. We present a framework for the holistic investigation of marine regime shifts that considers multiple exogenous drivers that interact with endogenous mechanisms to cause abrupt, catastrophic change. This framework takes into account the time-delayed synergies of these stressors, which erode the resilience of the ecosystem and eventually enable the crossing of ecological thresholds. Finally, considering that increased pressures in the marine environment are predicted by the current climate change assessments, in order to avoid major losses of ecosystem services, we suggest that marine management approaches should incorporate knowledge on environmental thresholds and develop tools that consider regime shift dynamics and characteristics. This grand challenge can only be achieved through a holistic view of marine ecosystem dynamics as evidenced by this theme issue.

  19. Greenland Meltwater and Arctic Circulation Regimes

    NASA Astrophysics Data System (ADS)

    Dukhovskoy, D. S.; Proshutinsky, A. Y.; Timmermans, M. L.; Myers, P. G.; Platov, G.

    2015-12-01

    Between 1948 and 1996, wind-driven components of ice drift and surface ocean currents experienced a well-pronounced decadal variability alternating between anticyclonic and cyclonic circulation regimes. During cyclonic regimes, low sea level atmospheric pressure dominated over the Arctic Ocean driving sea ice and the upper ocean clockwise; the Arctic atmosphere was relatively warm and humid and freshwater flux from the Arctic Ocean toward the sub-Arctic seas was intensified. During anticylonic circulation regimes, high sea level pressure dominated over the Arctic driving sea ice and ocean counter-clockwise; the atmosphere was cold and dry and the freshwater flux from the Arctic to the sub-Arctic seas was reduced. Since 1997, however, the Arctic system has been dominated by an anticyclonic circulation regime with a set of environmental parameters that are atypical for these regimes. Of essential importance is to discern the causes and consequences of the apparent break-down in the natural decadal variability of the Arctic climate system, and specifically: Why has the well-pronounced decadal variability observed in the 20th century been replaced by relatively weak interannual changes under anticyclonic circulation regime conditions in the 21st century? We discuss a hypothesis explaining the causes and mechanisms regulating the intensity and duration of Arctic circulation regimes, and speculate how changes in freshwater fluxes from Greenland impact environmental conditions and interrupt their decadal variability. In order to test this hypothesis, numerical experiments with several FAMOS (Forum for Arctic Modeling & Observational Synthesis) ice-ocean coupled models have been conducted. In these experiments, Greenland melt freshwater is tracked by passive tracers being constantly released along the Greenland coast. Propagation pathways and time scales of Greenland meltwater within the sub-Arctic seas are discussed.

  20. Identifying natural flow regimes using fish communities

    NASA Astrophysics Data System (ADS)

    Chang, Fi-John; Tsai, Wen-Ping; Wu, Tzu-Ching; Chen, Hung-kwai; Herricks, Edwin E.

    2011-10-01

    SummaryModern water resources management has adopted natural flow regimes as reasonable targets for river restoration and conservation. The characterization of a natural flow regime begins with the development of hydrologic statistics from flow records. However, little guidance exists for defining the period of record needed for regime determination. In Taiwan, the Taiwan Eco-hydrological Indicator System (TEIS), a group of hydrologic statistics selected for fisheries relevance, is being used to evaluate ecological flows. The TEIS consists of a group of hydrologic statistics selected to characterize the relationships between flow and the life history of indigenous species. Using the TEIS and biosurvey data for Taiwan, this paper identifies the length of hydrologic record sufficient for natural flow regime characterization. To define the ecological hydrology of fish communities, this study connected hydrologic statistics to fish communities by using methods to define antecedent conditions that influence existing community composition. A moving average method was applied to TEIS statistics to reflect the effects of antecedent flow condition and a point-biserial correlation method was used to relate fisheries collections with TEIS statistics. The resulting fish species-TEIS (FISH-TEIS) hydrologic statistics matrix takes full advantage of historical flows and fisheries data. The analysis indicates that, in the watersheds analyzed, averaging TEIS statistics for the present year and 3 years prior to the sampling date, termed MA(4), is sufficient to develop a natural flow regime. This result suggests that flow regimes based on hydrologic statistics for the period of record can be replaced by regimes developed for sampled fish communities.

  1. Learning Flow Regimes from Snapshot Data

    NASA Astrophysics Data System (ADS)

    Hemati, Maziar

    2015-11-01

    Fluid flow regimes are often categorized based on the qualitative patterns observed by visual inspection of the flow field. For example, bluff body wakes are traditionally classified based on the number and groupings of vortices shed per cycle (e.g., 2S, 2P, P+S), as seen in snapshots of the vorticity field. Subsequently, the existence and nature of these identified flow regimes can be explained through dynamical analyses of the fluid mechanics. Unfortunately, due to the need for manual inspection, the approach described above can be impractical for studies that seek to learn flow regimes from large volumes of numerical and/or experimental snapshot data. Here, we appeal to established techniques from machine learning and data-driven dynamical systems analysis to automate the task of learning flow regimes from snapshot data. Moreover, by appealing to the dynamical structure of the fluid flow, this approach also offers the potential to reveal flow regimes that may be overlooked by visual inspection alone. Here, we will introduce the methodology and demonstrate its capabilities and limitations in the context of several model flows.

  2. Dynamic treatment regimes: technical challenges and applications

    PubMed Central

    Lizotte, Daniel J.; Qian, Min; Pelham, William E.; Murphy, Susan A.

    2014-01-01

    Dynamic treatment regimes are of growing interest across the clinical sciences because these regimes provide one way to operationalize and thus inform sequential personalized clinical decision making. Formally, a dynamic treatment regime is a sequence of decision rules, one per stage of clinical intervention. Each decision rule maps up-to-date patient information to a recommended treatment. We briefly review a variety of approaches for using data to construct the decision rules. We then review a critical inferential challenge that results from nonregularity, which often arises in this area. In particular, nonregularity arises in inference for parameters in the optimal dynamic treatment regime; the asymptotic, limiting, distribution of estimators are sensitive to local perturbations. We propose and evaluate a locally consistent Adaptive Confidence Interval (ACI) for the parameters of the optimal dynamic treatment regime. We use data from the Adaptive Pharmacological and Behavioral Treatments for Children with ADHD Trial as an illustrative example. We conclude by highlighting and discussing emerging theoretical problems in this area. PMID:25356091

  3. Spin glasses in the nonextensive regime

    NASA Astrophysics Data System (ADS)

    Wittmann, Matthew; Young, A. P.

    2012-04-01

    Spin systems with long-range interactions are “nonextensive” if the strength of the interactions falls off sufficiently slowly with distance. It has been conjectured for ferromagnets and, more recently, for spin glasses that, everywhere in the nonextensive regime, the free energy is exactly equal to that for the infinite range model in which the characteristic strength of the interaction is independent of distance. In this paper we present the results of Monte Carlo simulations of the one-dimensional long-range spin glasses in the nonextensive regime. Using finite-size scaling, our results for the transition temperatures are consistent with this prediction. We also propose and provide numerical evidence for an analogous result for diluted long-range spin glasses in which the coordination number is finite, namely, that the transition temperature throughout the nonextensive regime is equal to that of the infinite-range model known as the Viana-Bray model.

  4. Gradual regime shifts in fairy circles.

    PubMed

    Zelnik, Yuval R; Meron, Ehud; Bel, Golan

    2015-10-01

    Large responses of ecosystems to small changes in the conditions--regime shifts--are of great interest and importance. In spatially extended ecosystems, these shifts may be local or global. Using empirical data and mathematical modeling, we investigated the dynamics of the Namibian fairy circle ecosystem as a case study of regime shifts in a pattern-forming ecosystem. Our results provide new support, based on the dynamics of the ecosystem, for the view of fairy circles as a self-organization phenomenon driven by water-vegetation interactions. The study further suggests that fairy circle birth and death processes correspond to spatially confined transitions between alternative stable states. Cascades of such transitions, possible in various pattern-forming systems, result in gradual rather than abrupt regime shifts. PMID:26362787

  5. Massive superstring scatterings in the Regge regime

    SciTech Connect

    He Song; Lee, Jen-Chi; Takahashi, Keijiro; Yang Yi

    2011-03-15

    We calculate four classes of high-energy massive string scattering amplitudes of fermionic string theory at arbitrary mass levels in the Regge regime (RR). We show that all four leading order amplitudes in the RR can be expressed in terms of the Kummer function of the second kind. Based on the summation algorithm of a set of extended signed Stirling number identities, we show that all four ratios calculated previously by the method of decoupling of zero-norm states among scattering amplitudes in the Gross regime can be extracted from this Kummer function in the RR. Finally, we conjecture and give evidence that the existence of these four Gross regime ratios in the RR persists to subleading orders in the Regge expansion of all high-energy fermionic string scattering amplitudes.

  6. Determination of the Hall Thruster Operating Regimes

    SciTech Connect

    L. Dorf; V. Semenov; Y. Raitses; N.J. Fisch

    2002-04-09

    A quasi one-dimensional (1-D) steady-state model of the Hall thruster is presented. For the same discharge voltage two operating regimes are possible -- with and without the anode sheath. For given mass flow rate, magnetic field profile and discharge voltage a unique solution can be constructed, assuming that the thruster operates in one of the regimes. However, we show that for a given temperature profile the applied discharge voltage uniquely determines the operating regime: for discharge voltages greater than a certain value, the sheath disappears. That result is obtained over a wide range of incoming neutral velocities, channel lengths and widths, and cathode plane locations. It is also shown that a good correlation between the quasi 1-D model and experimental results can be achieved by selecting an appropriate electron mobility and temperature profile.

  7. Gradual regime shifts in fairy circles

    PubMed Central

    Zelnik, Yuval R.; Meron, Ehud; Bel, Golan

    2015-01-01

    Large responses of ecosystems to small changes in the conditions—regime shifts—are of great interest and importance. In spatially extended ecosystems, these shifts may be local or global. Using empirical data and mathematical modeling, we investigated the dynamics of the Namibian fairy circle ecosystem as a case study of regime shifts in a pattern-forming ecosystem. Our results provide new support, based on the dynamics of the ecosystem, for the view of fairy circles as a self-organization phenomenon driven by water–vegetation interactions. The study further suggests that fairy circle birth and death processes correspond to spatially confined transitions between alternative stable states. Cascades of such transitions, possible in various pattern-forming systems, result in gradual rather than abrupt regime shifts. PMID:26362787

  8. Fermi's golden rule beyond the Zeno regime

    NASA Astrophysics Data System (ADS)

    Debierre, Vincent; Goessens, Isabelle; Brainis, Edouard; Durt, Thomas

    2015-08-01

    We reconsider the problem of the spontaneous emission of light by an excited atomic state. We scrutinize the survival probability of this excited state for very short times, in the so-called Zeno regime, for which we show that the dynamics is dictated by a coherent, in-phase, response of the on-shell and off-shell vacuum modes. We also develop a perturbative approach in order to interpolate between different temporal regimes: the Zeno, golden rule (linear), and Wigner-Weisskopf (exponential) regimes. We compare results obtained with the E ̂.x ̂ and A ̂.p ̂ interaction Hamiltonians, using successively the dipole approximation and the exact coupling.

  9. Massive superstring scatterings in the Regge regime

    NASA Astrophysics Data System (ADS)

    He, Song; Lee, Jen-Chi; Takahashi, Keijiro; Yang, Yi

    2011-03-01

    We calculate four classes of high-energy massive string scattering amplitudes of fermionic string theory at arbitrary mass levels in the Regge regime (RR). We show that all four leading order amplitudes in the RR can be expressed in terms of the Kummer function of the second kind. Based on the summation algorithm of a set of extended signed Stirling number identities, we show that all four ratios calculated previously by the method of decoupling of zero-norm states among scattering amplitudes in the Gross regime can be extracted from this Kummer function in the RR. Finally, we conjecture and give evidence that the existence of these four Gross regime ratios in the RR persists to subleading orders in the Regge expansion of all high-energy fermionic string scattering amplitudes.

  10. Transient regimes and crossover for epitaxial surfaces.

    PubMed

    Haselwandter, Christoph A; Vvedensky, Dimitri D

    2010-02-01

    We apply a formalism for deriving stochastic continuum equations associated with lattice models to obtain equations governing the transient regimes of epitaxial growth for various experimental scenarios and growth conditions. The first step of our methodology is the systematic transformation of the lattice model into a regularized stochastic equation of motion that provides initial conditions for differential renormalization-group (RG) equations for the coefficients in the regularized equation. The solutions of the RG equations then yield trajectories that describe the original model from the transient regimes, which are of primary experimental interest, to the eventual crossover to the asymptotically stable fixed point. We first consider regimes defined by the relative magnitude of deposition noise and diffusion noise. If the diffusion noise dominates, then the early stages of growth are described by the Mullins-Herring (MH) equation with conservative noise. This is the classic regime of molecular-beam epitaxy. If the diffusion and deposition noise are of comparable magnitude, the transient equation is the MH equation with nonconservative noise. This behavior has been observed in a recent report on the growth of aluminum on silicone oil surfaces [Z.-N. Fang, Thin Solid Films 517, 3408 (2009)]. Finally, the regime where deposition noise dominates over diffusion noise has been observed in computer simulations, but does not appear to have any direct experimental relevance. For initial conditions that consist of a flat surface, the Villain-Lai-Das Sarma (VLDS) equation with nonconservative noise is not appropriate for any transient regime. If, however, the initial surface is corrugated, the relative magnitudes of terms can be altered to the point where the VLDS equation with conservative noise does indeed describe transient growth. This is consistent with the experimental analysis of growth on patterned surfaces [H.-C. Kan, Phys. Rev. Lett. 92, 146101 (2004); T

  11. Statistical regimes of random laser fluctuations

    SciTech Connect

    Lepri, Stefano; Cavalieri, Stefano; Oppo, Gian-Luca; Wiersma, Diederik S.

    2007-06-15

    Statistical fluctuations of the light emitted from amplifying random media are studied theoretically and numerically. The characteristic scales of the diffusive motion of light lead to Gaussian or power-law (Levy) distributed fluctuations depending on external control parameters. In the Levy regime, the output pulse is highly irregular leading to huge deviations from a mean-field description. Monte Carlo simulations of a simplified model which includes the population of the medium demonstrate the two statistical regimes and provide a comparison with dynamical rate equations. Different statistics of the fluctuations helps to explain recent experimental observations reported in the literature.

  12. On the regimes of charge reversal.

    PubMed

    Jiménez-Angeles, Felipe; Lozada-Cassou, Marcelo

    2008-05-01

    Charge reversal of the planar electrical double layer is studied by means of a well known integral equation theory. By a numerical analysis, a diagram is constructed with the onset points of charge reversal in the space of the fundamental variables of the system. Within this diagram, two regimes of charge reversal are identified, which are referred to as oscillatory and nonoscillatory. We found that these two regimes can be distinguished through a simple formula. Furthermore, a symmetry between electrostatic and size correlations in charge reversal is exhibited. Agreement of our results with other theories and molecular simulations data is discussed. PMID:18465930

  13. Regimes of flow past a vortex generator

    NASA Astrophysics Data System (ADS)

    Velte, C. M.; Okulov, V. L.; Naumov, I. V.

    2012-04-01

    A complete parametric investigation of the development of multi-vortex regimes in a wake past simple vortex generator has been carried out. It is established that the vortex structure in the wake is much more complicated than a simple monopole tip vortex. The vortices were studied by stereoscopic particle image velocimetry (SPIV). Based on the obtained SPIV data, a map of the regimes of flow past the vortex generator has been constructed. One region with a developed stable multivortex system on this map reaches the vicinity of the optimum angle of attack of the vortex generator.

  14. Anomalous Hall effect in localization regime

    NASA Astrophysics Data System (ADS)

    Wu, Lin; Zhu, Kai; Yue, Di; Tian, Yuan; Jin, Xiaofeng

    2016-06-01

    The anomalous Hall effect in the ultrathin film regime is investigated in Fe(001)(1-3 nm) films epitaxial on MgO(001). The logarithmic localization correction to longitudinal resistivity and anomalous Hall resistivity are observed at low temperature. We identify that the coefficient of skew scattering has a reduction from metallic to localized regime, while the contribution of side jump has inconspicuous change except for a small drop below 10 K. Furthermore, we discover that the intrinsic anomalous Hall conductivity decreases with the reduction of thickness below 2 nm. Our results provide unambiguous experimental evidence to clarify the problem of localization correction to the anomalous Hall effect.

  15. Supercurrent in the quantum Hall regime

    NASA Astrophysics Data System (ADS)

    Amet, F.; Ke, C. T.; Borzenets, I. V.; Wang, J.; Watanabe, K.; Taniguchi, T.; Deacon, R. S.; Yamamoto, M.; Bomze, Y.; Tarucha, S.; Finkelstein, G.

    2016-05-01

    A promising route for creating topological states and excitations is to combine superconductivity and the quantum Hall (QH) effect. Despite this potential, signatures of superconductivity in the QH regime remain scarce, and a superconducting current through a QH weak link has been challenging to observe. We demonstrate the existence of a distinct supercurrent mechanism in encapsulated graphene samples contacted by superconducting electrodes, in magnetic fields as high as 2 tesla. The observation of a supercurrent in the QH regime marks an important step in the quest for exotic topological excitations, such as Majorana fermions and parafermions, which may find applications in fault-tolerant quantum computing.

  16. Supercurrent in the quantum Hall regime.

    PubMed

    Amet, F; Ke, C T; Borzenets, I V; Wang, J; Watanabe, K; Taniguchi, T; Deacon, R S; Yamamoto, M; Bomze, Y; Tarucha, S; Finkelstein, G

    2016-05-20

    A promising route for creating topological states and excitations is to combine superconductivity and the quantum Hall (QH) effect. Despite this potential, signatures of superconductivity in the QH regime remain scarce, and a superconducting current through a QH weak link has been challenging to observe. We demonstrate the existence of a distinct supercurrent mechanism in encapsulated graphene samples contacted by superconducting electrodes, in magnetic fields as high as 2 tesla. The observation of a supercurrent in the QH regime marks an important step in the quest for exotic topological excitations, such as Majorana fermions and parafermions, which may find applications in fault-tolerant quantum computing. PMID:27199424

  17. Comparative climatology of four marine stratocumulus regimes

    NASA Technical Reports Server (NTRS)

    Hanson, Howard P.

    1990-01-01

    The climatology of marine stratocumulus (MSc) cloud regimes off the west coasts of California, Peru, Morocco, and Angola are examined. Long-term, annual averages are presented for several quantities of interest in the four MSc regimes. The climatologies were constructed using the Comprehensive Ocean-Atmosphere Data Set (COADS). A 40 year time series of observations was extracted for 32 x 32 deg analysis domains. The data were taken from the monthly-averaged, 2 deg product. The resolution of the analysis is therefore limited to scales of greater than 200 km with submonthly variability not resolved. The averages of total cloud cover, sea surface temperature, and surface pressure are presented.

  18. Petrology, geochemistry, and fluid regime of tectonites

    NASA Astrophysics Data System (ADS)

    Letnikov, Feliks Artem'evich; Savel'Eva, Valentina Borisovna; Balyshev, Sergei Olegovich

    The book discusses the petrology, geochemisry, and fluid regime of the tectonite formation in rocks that differ with respect to the composition of their granulitic, amphylitic, and green-shale metamorphic facies. Tectonites in magma and metamorphic rocks of different composition are described in terms of their petrological, geochemical, and fluid-regime characteristics, and the pressure/temperature conditions of their formation. Using chemical and physical parameters, tectonites are classified according to their type models. The ore-generating capacity of tectonites in various rocks is estimated using a large geochemical database.

  19. Convective Regimes in Crystallizing Basaltic Magma Chambers

    NASA Astrophysics Data System (ADS)

    Gilbert, A. J.; Neufeld, J. A.; Holness, M. B.

    2015-12-01

    Cooling through the chamber walls drives crystallisation in crustal magma chambers, resulting in a cumulate pile on the floor and mushy regions at the walls and roof. The liquid in many magma chambers, either the bulk magma or the interstitial liquid in the mushy regions, may convect, driven either thermally, due to cooling, or compositionally, due to fractional crystallization. We have constructed a regime diagram of the possible convective modes in a system containing a basal mushy layer. These modes depend on the large-scale buoyancy forcing characterised by a global Rayleigh number and the proportion of the chamber height constituting the basal mushy region. We have tested this regime diagram using an analogue experimental system composed of a fluid layer overlying a pile of almost neutrally buoyant inert particles. Convection in this system is driven thermally, simulating magma convection above and within a porous cumulate pile. We observe a range of possible convective regimes, enabling us to produce a regime diagram. In addition to modes characterised by convection of the bulk and interstitial fluid, we also observe a series of regimes where the crystal pile is mobilised by fluid motions. These regimes feature saltation and scouring of the crystal pile by convection in the bulk fluid at moderate Rayleigh numbers, and large crystal-rich fountains at high Rayleigh numbers. For even larger Rayleigh numbers the entire crystal pile is mobilised in what we call the snowglobe regime. The observed mobilisation regimes may be applicable to basaltic magma chambers. Plagioclase in basal cumulates crystallised from a dense magma may be a result of crystal mobilisation from a plagioclase-rich roof mush. Compositional convection within such a mush could result in disaggregation, enabling the buoyant plagioclase to be entrained in relatively dense descending liquid plumes and brought to the floor. The phenocryst load in porphyritic lavas is often interpreted as a

  20. Delinating Thermohaline Double-Diffusive Rayleigh Regimes

    NASA Astrophysics Data System (ADS)

    Graf, T.; Walther, M.; Kolditz, O.; Liedl, R.

    2013-12-01

    In natural systems, convective flow induced from density differences may occur in near-coastal aquifers, atmospheric boundary layers, oceanic streams or within the earth crust. Whether an initially stable, diffusive regime evolves into a convective (stable or chaotic) regime, or vice versa, depends on the system's framing boundary conditions. A conventional parameter to express the relation between diffusive and convective forces of such a density-driven regime is Rayleigh number (Ra). While most systems are mainly dominated by only a single significant driving force (i.e. only temperature or salinity), some systems need to consider two boundary processes (e.g. deep, thus warm, haline flow in porous media). In that case, a two-dimensional, 'double-diffusive' Rayleigh system can be defined. Nield (1998) postulated a boundary between diffusive and convective regime at RaT + RaC = 4pi^2 in the first quadrant (Q1), with Rayleigh numbers for temperature and concentration respectively. The boundary in the forth quadrant (Q4) could not exactly be determined, yet the approximate position estimated. Simulations with HydroGeoSphere (Therrien, 2010) using a vertical, quadratic, homogeneous, isotropic setup confirmed the existence of the 4pi^2-boundary and revealed additional regimes (diffusive, single-roll, double-roll, chaotic) in Q1. Also, non-chaotic, oscillating patterns could be identified in Q4. More detailed investigations with OpenGeoSys (Kolditz, 2012) confirmed the preceding HGS results, and, using a 1:10-scaled domain (height:length), uncovered even more distinctive regimes (diffusive, minimum ten roles, supposely up to 25 roles, and chaotic?) in Q1, while again, oscillating patterns were found in the transition zone between diffusive and chaotic regimes in Q4. Output of numerical simulations from Q1 and Q4 show the mentioned regimes (diffusive, stable-convective, stable-oscillatory, chaotic) while results are displayed in context of a possible delination between

  1. H-Ras Increases Urokinase Expression and Cell Invasion in Genetically Modified Human Astrocytes Through Ras/Raf/MEK Signaling Pathway

    PubMed Central

    ZHAO, YUNGE; XIAO, AIZHEN; DIPIERRO, CHARLES G.; ABDEL-FATTAH, RANA; AMOS, SAMSON; REDPATH, GERARD T.; CARPENTER, JOAN E.; PIEPER, RUSSELL O.; HUSSAINI, ISA M.

    2008-01-01

    Previous study reported that the activation of Ras pathway cooperated with E6/E7-mediated inactivation of p53/pRb to transform immortalized normal human astrocytes (NHA/hTERT) into intracranial tumors strongly resembling human astrocytomas. The mechanism of how H-Ras contributes to astrocytoma formation is unclear. Using genetically modified NHA cells (E6/E7/hTERT and E6/E7/hTERT/Ras cells) as models, we investigated the mechanism of Ras-induced tumorigenesis. The overexpression of constitutively active H-RasV12 in E6/E7/hTERT cells robustly increased the levels of urokinase plasminogen activator (uPA) mRNA, protein, activity and invasive capacity of the E6/E7/hTERT/Ras cells. However, the expressions of MMP-9 and MMP-2 did not significantly change in the E6/E7/hTERT and E6/E7/hTERT/Ras cells. Furthermore, E6/E7/hTERT/Ras cells also displayed higher level of uPA activity and were more invasive than E6/E7/hTERT cells in 3D culture, and formed an intracranial tumor mass in a NOD-SCID mouse model. uPA specific inhibitor (B428) and uPA neutralizing antibody decreased uPA activity and invasion in E6/E7/hTERT/Ras cells. uPA-deficient U-1242 glioblastoma cells were less invasive in vitro and exhibited reduced tumor growth and infiltration into normal brain in xenograft mouse model. Inhibitors of Ras (FTA), Raf (Bay 54−9085) and MEK (UO126), but not of phosphatidylinositol 3-kinase (PI3K) (LY294002) and of protein kinase C (BIM) pathways, inhibited uPA activity and cell invasion. Our results suggest that H-Ras increased uPA expression and activity via the Ras/Raf/MEK signaling pathway leading to enhanced cell invasion and this may contribute to increased invasive growth properties of astrocytomas. PMID:18383343

  2. Cross-talk of anosmin-1, the protein implicated in X-linked Kallmann's syndrome, with heparan sulphate and urokinase-type plasminogen activator.

    PubMed

    Hu, Youli; González-Martínez, David; Kim, Soo-Hyun; Bouloux, Pierre Marc Gilles

    2004-12-15

    Defective function of anosmin-1, the protein encoded by KAL-1, underlies X-linked Kallmann's syndrome (X-KS), a human hereditary developmental disorder. Anosmin-1 appears to play a role in neurite outgrowth and axon branching, although molecular mechanisms of its action are still unknown. Anosmin-1 contains a WAP (whey acidic protein-like) domain and four contiguous FnIII (fibronectin-like type III) repeats; its WAP domain shows similarity to known serine protease inhibitors, whereas the FnIII domains contain HS (heparan sulphate)-binding sequences. To investigate the functional role of these domains, we have generated both wild-type and mutant recombinant anosmin-1 proteins using a Drosophila S2 cell expression system. Here we present the first biochemical evidence demonstrating the high-binding affinity between HS and anosmin-1, as measured by SPR (surface plasmon resonance) (K(d)=2 nM). The FnIII domains, particularly the first, are essential for dose-dependent HS binding and HS-mediated cell surface association. Furthermore, we have identified uPA (urokinase-type plasminogen activator) as an anosmin-1 interactant. Anosmin-1 significantly enhances the amidolytic activity of uPA in vitro; and anosmin-1-HS-uPA co-operation induces cell proliferation in the PC-3 prostate carcinoma cell line. Both the HS interaction and an intact WAP domain are required for the mitogenic activity of anosmin-1. These effects appear to be mediated by a direct protein interaction between anosmin-1 and uPA, since anosmin-1-uPA could be co-immunoprecipitated from PC-3 cell lysates, and their direct binding with high affinity (K(d)=6.91 nM) was demonstrated by SPR. We thus propose that anosmin-1 may modulate the catalytic activity of uPA and its signalling pathway, whereas HS determines cell surface localization of the anosmin-1-uPA complex. PMID:15324302

  3. A combination of desmopressin and docetaxel inhibit cell proliferation and invasion mediated by urokinase-type plasminogen activator (uPA) in human prostate cancer cells

    SciTech Connect

    Sasaki, Hiroshi; Klotz, Laurence H.; Sugar, Linda M.; Kiss, Alexander; Venkateswaran, Vasundara

    2015-08-28

    Background: This study was designed to assess the effectiveness of a combination treatment using both desmopressin and docetaxel in prostate cancer treatment. Desmopressin is a well-known synthetic analogue of the antidiuretic hormone vasopressin. It has recently been demonstrated to inhibit tumor progression and metastasis in in vivo models. Docetaxel is widely used for the treatment of castration resistant prostate cancer (CRPC) patients. However, durable responses have been uncommon to date. In this study, we investigated the anti-tumor effect of desmopressin in combination with docetaxel in vitro and in vivo. Methods: Two prostate cancer cells (PC3, LNCaP) were treated with different concentrations of desmopressin alone, docetaxel alone, and a combination of desmopressin and docetaxel. Cell proliferation was determined by MTS assay. The anti-invasive and anti-migration potential of desmopressin and in combination with docetaxel were examined by wound healing assay, migration chamber assay, and matrigel invasion assay. Results: The combination of desmopressin and docetaxel resulted in a significant inhibition of PC3 and LNCaP cell proliferation (p < 0.01). Additionally, cell migration and invasion were also inhibited by the combination when compared to that of either treatment alone in PC3 cells (p < 0.01). The anti-tumor effect of this combination treatment was associated with down-regulation of both urokinase-type plasminogen activator (uPA) and matrix metalloproteinase (MMP-2 and MMP-9) in PC3 cells. Conclusions: We are the first to elucidate the anti-tumor and anti-metastatic potential of desmopressin in combination with docetaxel in a prostate cancer model via the uPA-MMP pathway. Our finding could potentially contribute to the therapeutic profile of desmopressin and enhance the efficacy of docetaxel based treatment for CRPC. - Highlights: • Desmopressin inhibits cell proliferation in prostate cancer cells. • The expression of cyclin A and CDK2

  4. Nicotine stimulates urokinase-type plasminogen activator receptor expression and cell invasiveness through mitogen-activated protein kinase and reactive oxygen species signaling in ECV304 endothelial cells

    SciTech Connect

    Khoi, Pham Ngoc; Park, Jung Sun; Kim, Nam Ho; Jung, Young Do

    2012-03-01

    Urokinase-type plasminogen activator receptor (uPAR) expression is elevated during inflammation, tissue remodeling and in many human cancers. This study investigated the effect of nicotine, a major alkaloid in tobacco, on uPAR expression and cell invasiveness in ECV304 endothelial cells. Nicotine stimulated uPAR expression in a dose-dependent manner and activated extracellular signal-regulated kinases-1/2 (Erk-1/2), c-Jun amino-terminal kinase (JNK) and p38 mitogen activated protein kinase (MAPK). Specific inhibitors of MEK-1 (PD98059) and JNK (SP600125) inhibited the nicotine-induced uPAR expression, while the p38 MAPK inhibitor SB203580 did not. Expression vectors encoding dominant negative MEK-1 (pMCL-K97M) and JNK (TAM67) also prevented nicotine-induced uPAR promoter activity. The intracellular hydrogen peroxide (H{sub 2}O{sub 2}) content was increased by nicotine treatment. The antioxidant N-acetylcysteine prevented nicotine-activated production of reactive oxygen species (ROS) and uPAR expression. Furthermore, exogenous H{sub 2}O{sub 2} increased uPAR mRNA expression. Deleted and site-directed mutagenesis demonstrated the involvement of the binding sites of transcription factor nuclear factor-kappaB (NF-κB) and activator protein (AP)-1 in the nicotine-induced uPAR expression. Studies with expression vectors encoding mutated NF-κB signaling molecules and AP-1 decoy confirmed that NF-κB and AP-1 were essential for the nicotine-stimulated uPAR expression. MAPK (Erk-1/2 and JNK) and ROS functioned as upstream signaling molecules in the activation of AP-1 and NF-κB, respectively. In addition, ECV304 endothelial cells treated with nicotine displayed markedly enhanced invasiveness, which was partially abrogated by uPAR neutralizing antibodies. The data indicate that nicotine induces uPAR expression via the MAPK/AP-1 and ROS/NF-κB signaling pathways and, in turn, stimulates invasiveness in human ECV304 endothelial cells. -- Highlights: ► Endothelial cells

  5. Urokinase-type Plasminogen Activator Receptor (uPAR)-mediated Regulation of WNT/β-Catenin Signaling Is Enhanced in Irradiated Medulloblastoma Cells*

    PubMed Central

    Asuthkar, Swapna; Gondi, Christopher S.; Nalla, Arun Kumar; Velpula, Kiran Kumar; Gorantla, Bharathi; Rao, Jasti S.

    2012-01-01

    Urokinase plasminogen activator receptor (uPAR) is known to promote invasion, migration, and metastasis in cancer cells. In this report, we showed that ionizing radiation (IR)-induced uPAR has a role in WNT-β-catenin signaling and mediates induction of cancer stem cell (CSC)-like properties in medulloblastoma cell lines UW228 and D283. We observed that IR induced the expression of uPAR and CSC markers, such as Musashi-1 and CD44, and activated WNT-7a-β-catenin signaling molecules. Overexpression of uPAR alone or with IR treatment led to increased WNT-7a-β-catenin-TCF/LEF-mediated transactivation, thereby promoting cancer stemness. In contrast, treatment with shRNA specific for uPAR (pU) suppressed WNT-7a-β-catenin-TCF/LEF-mediated transactivation both in vitro and in vivo. Quercetin, a potent WNT/β-catenin inhibitor, suppressed uPAR and uPAR-mediated WNT/β-catenin activation, and furthermore, addition of recombinant human WNT-7a protein induced uPAR, indicating the existence of a mutual regulatory relationship between uPAR and WNT/β-catenin signaling. We showed that uPAR was physically associated with the WNT effector molecule β-catenin on the membrane, cytoplasm, and nucleus of IR-treated cells and CSC. Most interestingly, we demonstrated for the first time that localization of uPAR in the nucleus was associated with transcription factors (TF) and their specific response elements. We observed from uPAR-ChIP, TF protein, and protein/DNA array analyses that uPAR associates with activating enhancer-binding protein 2α (AP2a) and mediates β-catenin gene transcription. Moreover, association of uPAR with the β-catenin·TCF/LEF complex and various other TF involved during embryonic development and cancer indicates that uPAR is a potent activator of stemness, and targeting of uPAR in combination with radiation has significant therapeutic implications. PMID:22511755

  6. Urokinase-type plasminogen activator receptor (uPAR)-mediated regulation of WNT/β-catenin signaling is enhanced in irradiated medulloblastoma cells.

    PubMed

    Asuthkar, Swapna; Gondi, Christopher S; Nalla, Arun Kumar; Velpula, Kiran Kumar; Gorantla, Bharathi; Rao, Jasti S

    2012-06-01

    Urokinase plasminogen activator receptor (uPAR) is known to promote invasion, migration, and metastasis in cancer cells. In this report, we showed that ionizing radiation (IR)-induced uPAR has a role in WNT-β-catenin signaling and mediates induction of cancer stem cell (CSC)-like properties in medulloblastoma cell lines UW228 and D283. We observed that IR induced the expression of uPAR and CSC markers, such as Musashi-1 and CD44, and activated WNT-7a-β-catenin signaling molecules. Overexpression of uPAR alone or with IR treatment led to increased WNT-7a-β-catenin-TCF/LEF-mediated transactivation, thereby promoting cancer stemness. In contrast, treatment with shRNA specific for uPAR (pU) suppressed WNT-7a-β-catenin-TCF/LEF-mediated transactivation both in vitro and in vivo. Quercetin, a potent WNT/β-catenin inhibitor, suppressed uPAR and uPAR-mediated WNT/β-catenin activation, and furthermore, addition of recombinant human WNT-7a protein induced uPAR, indicating the existence of a mutual regulatory relationship between uPAR and WNT/β-catenin signaling. We showed that uPAR was physically associated with the WNT effector molecule β-catenin on the membrane, cytoplasm, and nucleus of IR-treated cells and CSC. Most interestingly, we demonstrated for the first time that localization of uPAR in the nucleus was associated with transcription factors (TF) and their specific response elements. We observed from uPAR-ChIP, TF protein, and protein/DNA array analyses that uPAR associates with activating enhancer-binding protein 2α (AP2a) and mediates β-catenin gene transcription. Moreover, association of uPAR with the β-catenin·TCF/LEF complex and various other TF involved during embryonic development and cancer indicates that uPAR is a potent activator of stemness, and targeting of uPAR in combination with radiation has significant therapeutic implications. PMID:22511755

  7. Involvement of nitric oxide synthase in matrix metalloproteinase-9- and/or urokinase plasminogen activator receptor-mediated glioma cell migration

    PubMed Central

    2013-01-01

    Background Src tyrosine kinase activates inducible nitric oxide synthase (iNOS) and, in turn, nitric oxide production as a means to transduce cell migration. Src tyrosine kinase plays a key proximal role to control α9β1 signaling. Our recent studies have clearly demonstrated the role of α9β1 integrin in matrix metalloproteinase-9 (MMP-9) and/or urokinase plasminogen activator receptor (uPAR)-mediated glioma cell migration. In the present study, we evaluated the involvement of α9β1 integrin-iNOS pathway in MMP-9- and/or uPAR-mediated glioma cell migration. Methods MMP-9 and uPAR shRNAs and overexpressing plasmids were used to downregulate and upregulate these molecules, respectively in U251 glioma cells and 5310 glioma xenograft cells. The effect of treatments on migration and invasion potential of these glioma cells were assessed by spheroid migration, wound healing, and Matrigel invasion assays. In order to attain the other objectives we also performed immunocytochemical, immunohistochemical, RT-PCR, Western blot and fluorescence-activated cell sorting (FACS) analysis. Results Immunohistochemical analysis revealed the prominent association of iNOS with glioblastoma multiforme (GBM). Immunofluorescence analysis showed prominent expression of iNOS in glioma cells. MMP-9 and/or uPAR knockdown by respective shRNAs reduced iNOS expression in these glioma cells. RT-PCR analysis revealed elevated iNOS mRNA expression in either MMP-9 or uPAR overexpressed glioma cells. The migration potential of MMP-9- and/or uPAR-overexpressed U251 glioma cells was significantly inhibited after treatment with L-NAME, an inhibitor of iNOS. Similarly, a significant inhibition of the invasion potential of the control or MMP-9/uPAR-overexpressed glioma cells was noticed after L-NAME treatment. A prominent reduction of iNOS expression was observed in the tumor regions of nude mice brains, which were injected with 5310 glioma cells, after MMP-9 and/or uPAR knockdown. Protein expressions

  8. Staurosporine induces ganglion cell differentiation in part by stimulating urokinase-type plasminogen activator expression and activation in the developing chick retina

    SciTech Connect

    Kim, Yeoun-Hee; Chang, Yongmin; Jung, Jae-Chang

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer Staurosporine mediates stimulation of RGC differentiation in vitro cultured retinal neuroblasts. Black-Right-Pointing-Pointer Staurosporine mediates uPA activation during RGC differentiation in vitro. Black-Right-Pointing-Pointer Inhibition of uPA blocks the staurosporine mediated RGC differentiation both in vitro and in ovo. Black-Right-Pointing-Pointer Thus, uPA may play a role in the staurosporine-mediated stimulation of RGC differentiation. -- Abstract: Here, we investigated whether staurosporine-mediated urokinase-type plasminogen activator (uPA) activation is involved in retinal ganglion cell (RGC) differentiation. Retinal cells were isolated from developing chick retinas at embryonic day 6 (E6). Relatively few control cells grown in serum-free medium started to form processes by 12 h. In contrast, staurosporine-treated cells had processes within 3 h, and processes were evident at 8 h. Immunofluorescence staining showed that Tuj-1-positive cells with shorter neurites could be detected in control cultures at 18 h, whereas numerous Tuj-1 positive ganglion cells with longer neuritic extensions were seen in staurosporine-treated cultures. BrdU-positive proliferating cells were more numerous in control cultures than in staurosporine-treated cultures, and the BrdU staining was not detected in post-mitotic Tuj-1 positive ganglion cells. Western blotting of cell lysates showed that staurosporine induced high levels of the active form of uPA. The staurosporine-induced uPA signal was localized predominantly in the soma, neurites and axons of Tuj-1-positive ganglion cells. Amiloride, an inhibitor of uPA, markedly reduced staurosporine-induced Tuj-1 staining, neurite length, neurite number, and uPA staining versus controls. In developing retinas in ovo, amiloride administration remarkably reduced the staurosporine-induced uPA staining and RGC differentiation. Taken together, our in vitro and in vivo data collectively indicate that

  9. Production of a urokinase plasminogen activator-IgG fusion protein (uPA-IgG) in the baculovirus expression system.

    PubMed

    Kost, T A; Ignar, D M; Clay, W C; Andrews, J; Leray, J D; Overton, L; Hoffman, C R; Kilpatrick, K E; Ellis, B; Emerson, D L

    1997-04-29

    Numerous studies have demonstrated the importance of urokinase plasminogen activator (uPA) and its receptor, uPAR, in the processes of tumor progression and metastasis. Thus, the uPA/uPAR interaction may represent an important target for inhibiting metastatic disease. The baculovirus expression system was used to produce high levels of a secreted uPA-Immunoglobulin G fusion protein (uPA-IgG) which could then be used for displacing uPA from the surface of tumor cells. The recombinant uPA-IgG fusion protein was placed under the control of either the viral polyhedrin promoter or a copy of the viral basic protein promoter. Recombinant viruses were then used to infect Sf9 and BTI-Tn-5B1-4 cells. Infection of both cell types resulted in the production of secreted uPA-IgG. The molecular mass of the secreted protein as determined by SDS-PAGE was approximately 40 kDa. The highest level of secreted uPA-IgG, 444 microg/ml, was found in the culture medium of BTI-Tn-5B1-4 cells 72 h post-infection with the basic protein promoter-uPA-IgG virus. In the case of Sf9 cells, the highest level of secreted protein was 195 microg/ml. The amount of cell-associated uPA-IgG in infected BTI-Tn-5B1-4 cells was significantly less than that of infected Sf9 cells, reflecting the superior secretory capability of the BTI-Tn-5B1-4 cells. The uPA-IgG was readily purified using a combination of zinc chelate and sephacryl S-100 column chromatography. Routinely, greater than 100 mg of greater than 95% pure protein could be obtained per liter of culture medium collected at 72 h post-infection of BTI-Tn-5B1-4 cells with the basic protein promoter virus. BIAcore analysis and competition binding assays using LOX human malignant melanoma cells expressing uPAR indicated that the purified recombinant protein possessed similar ligand binding characteristics to that of human uPA. PMID:9185859

  10. Drag-force regimes in granular impact

    NASA Astrophysics Data System (ADS)

    Tiwari, Mukesh; Mohan, T. R. Krishna; Sen, Surajit

    2014-12-01

    We study the penetration dynamics of a projectile incident normally on a substrate comprising of smaller granular particles in three-dimensions using the discrete element method. Scaling of the penetration depth is consistent with experimental observations for small velocity impacts. Our studies are consistent with the observation that the normal or drag force experienced by the penetrating grain obeys the generalized Poncelet law, which has been extensively invoked in understanding the drag force in the recent experimental data. We find that the normal force experienced by the projectile consists of position and kinetic-energy-dependent pieces. Three different penetration regimes are identified in our studies for low-impact velocities. The first two regimes are observed immediately after the impact and in the early penetration stage, respectively, during which the drag force is seen to depend on the kinetic energy. The depth dependence of the drag force becomes significant in the third regime when the projectile is moving slowly and is partially immersed in the substrate. These regimes relate to the different configurations of the bed: the initial loose surface packed state, fluidized bed below the region of impact, and the state after the crater formation commences.