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1
Abramov, V. V. "Single-spin asymmetry in pp and pA-collisions." Journal of Physics: Conference Series 678 (February 5, 2016): 012039. http://dx.doi.org/10.1088/1742-6596/678/1/012039.
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Lijnen, H. R., L. Nelles, B. Van Hoef, F. De Cock, and D. Collen. "Inhibition in Purified Systems and in Human Plasma of Chimaeric Plasminogen Activators Consisting of the NH2-Terminal Region of Tissue-Type Plasminogen Activator and the COOH-Terminal Region of UrokinaseType Plasminogen Activator." Thrombosis and Haemostasis 60, no. 02 (1988): 247–50. http://dx.doi.org/10.1055/s-0038-1647039.
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SummaryRecombinant chimaeric molecules between tissue-type plasminogen activator (t-PA) and single chain urokinase-type plasminogen activator (scu-PA) or two chain urokinase-type plasminogen activator (tcu-PA) have intact enzymatic properties of scu-PA or tcu-PA towards natural and synthetic substrates (Nelles et al., J Biol Chem 1987; 262: 10855-10862). In the present study, we have compared the reactivity with inhibitors of both the single chain and two chain variants of recombinant u-PA and two recombinant chimaeric molecules between t-PA and scu-PA (t-PA/u-PA-s: amino acids 1-263 of t-PA and 144-411 of u-PA; t-PA/u-PA-e: amino acids 1-274 of t-PA and 138-411 of u-PA). Incubation with human plasma in the absence of a fibrin clot for 3 h at 37° C at equipotent concentrations (50% clot lysis in 2 h), resulted in significant fibrinogen breakdown (to about 40% of the normal value) for all two chain molecules, but not for their single chain counterparts. Preincubation of the plasminogen activators with plasma for 3 h at 37° C, resulted in complete inhibition of the fibrinolytic potency of the two chain molecules but did not alter the potency of the single chain molecules. Inhibition of the two chain molecules occurred with a t½ of approximately 45 min. The two chain variants were inhibited by the synthetic urokinase inhibitor Glu-Gly-Arg-CH2CCl with apparent second-order rate constants of 8,000-10,000 M−1s−1, by purified α2-antiplasmin with second-order rate constants of about 300 M−1s−1, and by plasminogen activator inhibitor-1 (PAI-1) with second-order rate constants of approximately 2 × 107 M−1s−1.It is concluded that the reactivity of single chain and two chain forms of t-PA/u-PA chimaers with inhibitors is very similar to that of the single and two chain forms of intact u-PA.
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Lijnen, H. R., B. Van Hoet, F. De Cock, and D. Collen. "Effect of Fibrin-Like Stimulators on the Activation of Plasminogen by Tissue-Type Plasminogen Activator (t-PA) - Studies with Active Site Mutagenized Plasminogen and Plasmin Resistant t-PA." Thrombosis and Haemostasis 64, no. 01 (1990): 061–68. http://dx.doi.org/10.1055/s-0038-1647254.
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SummaryThe activation of plasminogen by t-PA was measured in the presence and absence of fibrin stimulation, using natural human plasminogen (nPlg) and rPlg-Ala740, a recombinant plasminogen with the active site Ser740 mutagenaed to Ala. Recombinant wild type t-PA (rt-PA) was used as well as rt-PA -Glul275, a recombinant single chain t-PA in which the Arg of the plasmin sensitiv e Arg275- Ile276 peptide bond was substituted with Glu. Conversion of 125I-labeled single chain plasminogen to two-chain plasmin by wild-type or mutant t-PA, was quantitated by SDS gel electrophoresis and radioisotope counting of gel slices, and expressed as initial activation rates (v0 in pM s−1) per 1 μM enzyme. In the absence of fibrin stimulation, the vs for the activation of nPlg and rPlg-Ala740 with the single chain forms of both t-PAs were comparable (0.6 to 2.7 pM s−1) but were lower than with the corresponding two-chain forms (5.3 to 23 pM s−1). In the presence of 1 μM soluble fibrin monomer (desAAfibrin), the v0 for nPlg and rPlg-Ala740 by single chain rt-PA was also comparable (24 and, 33 pM s-1 respectively), whereas with 1 pM CNBr-digested fibrinogen, the vs for nPlg with single chain rt-PA was about 20-fold higher than that of rPlg-Ala740 (135 and 7.5 pM s−1 respectively). In contrast, the vs for nPlg and rPlg-Ala740 by single chain rt-PA- G1u275, two-chain rt-PA-G1u275 or two-chain rt-PA were comparable in the presence of either desAAfibrin or CNBr-digested fibrinogen.These findings confirm and establish: 1) that single chain t-PA is an active enzyme both in the presence and absence of fibrin stimulator; 2) that, in a system devoid of plasmin activity (rPlg- Ala740), the two-chain form of t-PA is about L5 times more active than the single chain form in the absence of fibrin but equipotent in the presence of desAAfibrin; and 3) that the mechanism of stimulation of plasminogen activation with single chain t-PA by CNBr-digested fibrinogen is different from that by soluble fibrin.
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Holvoet, P., Y. Laroche, JM Stassen, HR Lijnen, B. Van Hoef, F. De Cock, A. Van Houtven, Y. Gansemans, G. Matthyssens, and D. Collen. "Pharmacokinetic and thrombolytic properties of chimeric plasminogen activators consisting of a single-chain Fv fragment of a fibrin- specific antibody fused to single-chain urokinase." Blood 81, no. 3 (February 1, 1993): 696–703. http://dx.doi.org/10.1182/blood.v81.3.696.696.
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Abstract The pharmacokinetic and thrombolytic properties were determined of two recombinant single-chain chimeric plasminogen activators (PA) consisting of u-PA-33k, a low-molecular weight derivative of single- chain urokinase-type PA (scu-PA) comprising amino acids Ala132 through Leu411, and of either a single-chain variable region fragment (Fv) derived from the fibrin fragment D-dimer-specific monoclonal antibody MA-15C5 (K12G0S32) or of the deglycosylated single-chain Fv fragment obtained by substitution of Asn88 with Glu (K12G2S32). Following bolus injection in hamsters, clearances of recombinant scu-PA (rscu-PA) and of K12G0S32 were similar. In contrast, clearance of K12G2S32 was fourfold slower than that of rscu-PA. The thrombolytic potency (percent lysis per u-PA administered in milligrams per kilogram body weight) and specific thrombolytic activity (percent lysis per microgram per milliliter steady-state plasma u-PA antigen level) of these compounds were studied in hamsters with an experimental pulmonary embolus consisting of a human plasma clot injected via the jugular vein. The doses of K12G0S32 and K12G2S32 required to obtain maximal rate of clot lysis were sixfold and 11-fold lower than that of rscu-PA. The steady- state u-PA-related plasma antigen levels of K12G0S32 and K12G2S32 required to obtain maximal rate of clot lysis were 10-fold and fourfold lower than that of rscu-PA. Thus, targeting of K12G0S32 to the clot surface by means of its glycosylated Fv fragment results in a 10-fold increase of its specific thrombolytic activity and sixfold increase of its thrombolytic potency as compared with those of rscu-PA. Targeting of K12G2S32 to the clot surface by means of its deglycosylated Fv fragment results in only a twofold increase of its thrombolytic activity. However, its fourfold slower clearance, combined with its twofold higher specific thrombolytic activity, results in an 11-fold increase of its thrombolytic potency over that of rscu-PA. These findings indicate that the thrombolytic potency of chimeric antibody- targeted PA may be increased by increasing the specific thrombolytic activity, reducing the clearance, or both.
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Holvoet, P., Y. Laroche, JM Stassen, HR Lijnen, B. Van Hoef, F. De Cock, A. Van Houtven, Y. Gansemans, G. Matthyssens, and D. Collen. "Pharmacokinetic and thrombolytic properties of chimeric plasminogen activators consisting of a single-chain Fv fragment of a fibrin- specific antibody fused to single-chain urokinase." Blood 81, no. 3 (February 1, 1993): 696–703. http://dx.doi.org/10.1182/blood.v81.3.696.bloodjournal813696.
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The pharmacokinetic and thrombolytic properties were determined of two recombinant single-chain chimeric plasminogen activators (PA) consisting of u-PA-33k, a low-molecular weight derivative of single- chain urokinase-type PA (scu-PA) comprising amino acids Ala132 through Leu411, and of either a single-chain variable region fragment (Fv) derived from the fibrin fragment D-dimer-specific monoclonal antibody MA-15C5 (K12G0S32) or of the deglycosylated single-chain Fv fragment obtained by substitution of Asn88 with Glu (K12G2S32). Following bolus injection in hamsters, clearances of recombinant scu-PA (rscu-PA) and of K12G0S32 were similar. In contrast, clearance of K12G2S32 was fourfold slower than that of rscu-PA. The thrombolytic potency (percent lysis per u-PA administered in milligrams per kilogram body weight) and specific thrombolytic activity (percent lysis per microgram per milliliter steady-state plasma u-PA antigen level) of these compounds were studied in hamsters with an experimental pulmonary embolus consisting of a human plasma clot injected via the jugular vein. The doses of K12G0S32 and K12G2S32 required to obtain maximal rate of clot lysis were sixfold and 11-fold lower than that of rscu-PA. The steady- state u-PA-related plasma antigen levels of K12G0S32 and K12G2S32 required to obtain maximal rate of clot lysis were 10-fold and fourfold lower than that of rscu-PA. Thus, targeting of K12G0S32 to the clot surface by means of its glycosylated Fv fragment results in a 10-fold increase of its specific thrombolytic activity and sixfold increase of its thrombolytic potency as compared with those of rscu-PA. Targeting of K12G2S32 to the clot surface by means of its deglycosylated Fv fragment results in only a twofold increase of its thrombolytic activity. However, its fourfold slower clearance, combined with its twofold higher specific thrombolytic activity, results in an 11-fold increase of its thrombolytic potency over that of rscu-PA. These findings indicate that the thrombolytic potency of chimeric antibody- targeted PA may be increased by increasing the specific thrombolytic activity, reducing the clearance, or both.
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Santos, Fávero G., Bernardo R. B. de A. Leite, and André A. Mariano. "A multimode CMOS PA with a single propagation path." Analog Integrated Circuits and Signal Processing 108, no. 2 (June 9, 2021): 421–35. http://dx.doi.org/10.1007/s10470-021-01886-z.
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Iacono, Teresa, and Linda Cupples. "Assessment of Phonemic Awareness and Word Reading Skills of People With Complex Communication Needs." Journal of Speech, Language, and Hearing Research 47, no. 2 (April 2004): 437–49. http://dx.doi.org/10.1044/1092-4388(2004/035).
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A series of phonemic awareness (PA) and single-word reading tasks, which did not require spoken responses, was developed for administration to people with complex communication needs. The aims of the study were to (a) determine the construct validity of the PA tasks and (b) investigate the relationship between PA and single-word reading in adults with complex communication needs. Forty adults with physical and/or intellectual disability were administered these tasks and a standardized measure of receptive spoken vocabulary. In assessing construct validity, data from all participants, including those who used speech, were included in a factor analysis, which indicated that the PA tasks loaded onto a single factor. This factor was interpreted to be PA. The relationship between PA and single-word reading in adults with complex communication needs was determined using correlational and multiple regression analyses of data from 34 of the original participants who did not have functional speech skills. These analyses indicated that receptive spoken vocabulary accounted for a significant amount of variance on most tasks. Additional significant variance in performance on the single-word reading tasks was accounted for by performance on the PA tasks, in particular, Nonword Blending and Phoneme Analysis. These results indicate that the tasks developed provide a valid means of assessing PA and single-word reading skills. In addition, the results indicate that adults with complex communication needs demonstrate the same positive association between PA and reading as has been found in other groups of individuals with and without disability.
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Fischer, B. E. "Comparison of the effects of fibrin binding on the biochemical properties of single-chain tissue-type plasminogen activator (t-PA) and single-chain chimeric plasminogen activator (t-PA/scu-PA)." Blood Coagulation & Fibrinolysis 3, no. 1 (February 1992): 39–46. http://dx.doi.org/10.1097/00001721-199202000-00007.
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Stump, DC, JM Stassen, E. Demarsin, and D. Collen. "Comparative thrombolytic properties of single-chain forms of urokinase- type plasminogen activator." Blood 69, no. 2 (February 1, 1987): 592–96. http://dx.doi.org/10.1182/blood.v69.2.592.592.
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Abstract The specific thrombolytic properties of urokinase and three molecular forms of single-chain urokinase-type plasminogen activator (scu-PA) were compared in a human plasma milieu in vitro and in an experimental thrombosis model in rabbits. These scu-PA molecules included Mr 54,000 scu-PA from human urine (urinary scu-PA), scu-PA from conditioned media of a human lung adenocarcinoma cell line (CALU-3,ATCC,HTB-55) (cellular scu-PA) and an Mr 32,000 proteolytic derivative of cellular scu-PA (scu- PA-32k). All four molecular forms induced significant lysis of a 125I- labeled human plasma clot immersed in citrated human plasma at concentrations between 50 and 200 IU/mL. None of the four showed absolute fibrin-specificity, but at equivalent lytic dose the three single-chain forms appeared to cause less fibrinogen degradation and alpha 2-antiplasmin consumption than two-chain urokinase. In addition, the fibrinolytic potential of the three single-chain forms was largely maintained during pre-incubation in plasma for up to 48 hours whereas that of urokinase was completely inhibited. Intravenous (IV) infusion of cellular scu-PA or scu-PA-32k into rabbits with a 125I-labeled thrombus in the jugular vein caused significant dose-dependent lysis at concentrations ranging from 8,700 to 35,000 and from 9,000 to 36,000 IU/kg respectively. Clot lysis was accompanied by minor alpha 2- antiplasmin consumption or fibrinogen breakdown. In contrast, urokinase induced lysis at doses between 20,000 and 200,000 IU/kg, but at higher doses was associated with significant systemic activation of the fibrinolytic system. It is concluded that scu-PA obtained from CALU-3 cell cultures has identical thrombolytic properties to that obtained from urine. In addition, the scu-PA-32k proteolytic derivative has the same fibrin-specific thrombolytic properties as the intact molecule. Cellular scu-PA and scu-PA-32k may therefore constitute more readily available alternatives for clot-selective thrombolytic therapy in man.
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Stump, DC, JM Stassen, E. Demarsin, and D. Collen. "Comparative thrombolytic properties of single-chain forms of urokinase- type plasminogen activator." Blood 69, no. 2 (February 1, 1987): 592–96. http://dx.doi.org/10.1182/blood.v69.2.592.bloodjournal692592.
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The specific thrombolytic properties of urokinase and three molecular forms of single-chain urokinase-type plasminogen activator (scu-PA) were compared in a human plasma milieu in vitro and in an experimental thrombosis model in rabbits. These scu-PA molecules included Mr 54,000 scu-PA from human urine (urinary scu-PA), scu-PA from conditioned media of a human lung adenocarcinoma cell line (CALU-3,ATCC,HTB-55) (cellular scu-PA) and an Mr 32,000 proteolytic derivative of cellular scu-PA (scu- PA-32k). All four molecular forms induced significant lysis of a 125I- labeled human plasma clot immersed in citrated human plasma at concentrations between 50 and 200 IU/mL. None of the four showed absolute fibrin-specificity, but at equivalent lytic dose the three single-chain forms appeared to cause less fibrinogen degradation and alpha 2-antiplasmin consumption than two-chain urokinase. In addition, the fibrinolytic potential of the three single-chain forms was largely maintained during pre-incubation in plasma for up to 48 hours whereas that of urokinase was completely inhibited. Intravenous (IV) infusion of cellular scu-PA or scu-PA-32k into rabbits with a 125I-labeled thrombus in the jugular vein caused significant dose-dependent lysis at concentrations ranging from 8,700 to 35,000 and from 9,000 to 36,000 IU/kg respectively. Clot lysis was accompanied by minor alpha 2- antiplasmin consumption or fibrinogen breakdown. In contrast, urokinase induced lysis at doses between 20,000 and 200,000 IU/kg, but at higher doses was associated with significant systemic activation of the fibrinolytic system. It is concluded that scu-PA obtained from CALU-3 cell cultures has identical thrombolytic properties to that obtained from urine. In addition, the scu-PA-32k proteolytic derivative has the same fibrin-specific thrombolytic properties as the intact molecule. Cellular scu-PA and scu-PA-32k may therefore constitute more readily available alternatives for clot-selective thrombolytic therapy in man.
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Lijnen, H. R., P. D. Webb, B. Van Hoef, F. De Cock, J. M. Stassen, S. D. Prior, and D. Collen. "Biochemical and Biological Properties of a Recombinant Tissue-Type Plasminogen Activator Derived from the Rat JMI-229 Cell Line." Thrombosis and Haemostasis 67, no. 02 (1992): 239–47. http://dx.doi.org/10.1055/s-0038-1648419.
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SummaryRecombinant tissue-type plasminogen activator (rt-PA), produced by expression of the genomic t-PA DNA from the JMI-229 cell line, which is of rat origin, in the host cell line, was purified to homogeneity. JMI-229 rt-PA was obtained essentially as a single chain molecule which was quantitatively converted to a two-chain moiety by treatment with plasmin. The plasminogen activating potential of single chain JMI-229 rt-PA was 5-fold lower than that of commercially available human rt-PA (Actilyse®) in the absence of fibrin, but comparable in the presence of fibrin; it showed a concentration-dependent binding to fibrin, with a significantly more pronounced binding than Actilyse® at low fibrin concentration (85 ± 8% versus 20 ± 7% at 0.025 mg/ml fibrin; p = 0.004). In human plasma in the absence of fibrin, the concentrations of both single chain and two-chain JMI-229 rt-PA required to induce 50% fibrinogen degradation in 2 h, were about 15-fold higher than those of Actilyse®. Both single chain and two-chain forms of JMI-229 rt-PA and of Actilyse® induced a similar time- and concentration-dependent lysis of a 125I-fibrin-labeled plasma clot immersed in human plasma, in the absence of significant systemic fibrinolytic activation. Equally effective concentrations (causing 50% clot lysis in 2 h) were 0.11 or 0.10 pg/ml for single chain or two-chain JMI-229 rt-PA, as compared to 0.11 or 0.15 pg/ml for single chain or two-chain Actilyse®. Continuous infusion over 60 min of single chain JMI-229 rt-PA or Actilyse® in hamsters with a 125I-fibrin-labeled pulmonary embolus, revealed a very similar thrombolytic potency (clot lysis versus dose) and specific thrombolytic activity (clot lysis versus steady state plasma antigen level of t-PA). The initial plasma half-life following intravenous bolus injection of 0.10 mg/kg in hamsters was equally short for JMI-229 rt-PA or Actilyse® (1.2 or 1.4 min respectively).It is concluded that JMI-229 rt-PA has a higher fibrin-affinity and a higher fibrin-specificity in human plasma in the absence of fibrin than Actilyse®, but a comparable thrombolytic potency in a hamster pulmonary embolism model.
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Magalhães, Alexandre, Milton Severo, Roseanne Autran, Joana Araújo, Paula Santos, Maria Fátima Pina, and Elisabete Ramos. "Validation of a Single Question for the Evaluation of Physical Activity in Adolescents." International Journal of Sport Nutrition and Exercise Metabolism 27, no. 4 (August 2017): 361–69. http://dx.doi.org/10.1123/ijsnem.2016-0276.
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We aimed to assess the validity of a single question to evaluate leisure-time physical activity (PA) in adolescents. We included 209 participants (57.4% girls) aged 14–18 years from Porto, Portugal, evaluated as part of the SALTA project. A self-reported question with four answer options, designed for the EPITeen study, was used to classify the intensity level of usual leisure-time activities. Actigraph accelerometers were used to objectively measure total PA during 7 consecutive days. Since the accelerometers measured PA as a continuous variable, hierarchical cluster analysis was used to identify clusters of individuals with similar level of objectively measured PA. Correlations between self-reported and objective measures were evaluated through polychoric correlations. In girls, we found higher mean time on sedentary activities among those describing their leisure-time PA as “sitting”, and an increase on the time spent on light and moderate activities with increasing intensity of PA on self-reported classification. A similar trend was found in boys, but not reaching statistical significance. The correlation between the two measures of PA was 0.42 for girls and 0.46 for boys. We found an acceptable correlation between our single question and the objectively measured PA, showing that, although the single question is not adequate to quantify the intensity of the physical activity, it allows to rank adolescents according to leisure-time physical activity.
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Fry, Edward T. A., David L. Mack, and Burton E. Sobel. "The Nature of Synergy between Tissue-Type and Single Chain Urokinase-Type Plasminogen Activators." Thrombosis and Haemostasis 62, no. 03 (1989): 909–16. http://dx.doi.org/10.1055/s-0038-1651027.
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SummaryEnhancement of thrombolysis with combinations of tissue-type and single chain urokinase plasminogen activators (t-PA and scu-PA) has been demonstrated in vivo but has not been seen consistently in vitro. This study was designed to characterize interactions between t-PA and scu-PA with respect to rate of and extent of thrombolysis in vitro and to delineate mechanisms responsible. Combinations of t-PA and scu-PA at selected concentrations synergistically enhanced thrombolysis in vitro compared with thrombolysis induced by either activator alone. Enhanced thrombolysis did not occur at the expense of fibrin specificity since the extent of fibrinogenolysis and consumption of α2-antiplasmin were significantly less with synergistic combinations of t-PA and scu-PA compared with equi-effective concentrations of either activator alone. Attenuation of complex formation of t-PA and two chain u-PA (tcu-PA), formed from scu-PA, with plasma proteins did not appear to contribute to enhancement of thrombolysis as assessed by fibrin autography. Binding of 125I-t-PA to thrombi was increased by 27% at 1 hr and by 21% at 2 hr in the presence of scu-PA (p <0,001 for both). Conversion of scu-PA to tcu-PA was enhanced when thrombi were exposed to scu-PA in the presence of t-PA. Results of this study indicate that t-PA and scu-PA at selected concentrations enhance thrombolysis in vitro synergistically without compromising fibrin specificity. Enhanced binding of t-PA to thrombi in the presence of scu-PA and enhanced conversion of scu-PA to tcu-PA appear to contribute to synergy between t-PA and scu-PA for thrombolysis.
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Thakur, M., and J. B. Lando. "Growth, polymerization and oxidation characteristics of PA-PDA single crystals." Polymer 27, no. 12 (December 1986): 1963–66. http://dx.doi.org/10.1016/0032-3861(86)90190-4.
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Aerts, Rob J., Karin Gillis, and Hans Pannekoek. "Single-Chain and Two-Chain Tissue-Type Plasminogen Activator (t-PA) Bind Differently to Cultured Human Endothelial Cells." Thrombosis and Haemostasis 62, no. 02 (1989): 699–703. http://dx.doi.org/10.1055/s-0038-1646886.
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SummaryIt has recently been shown that the fibrinolytic components plasminogen and tissue-type plasminogen activator (t-PA) both bind to cultured human umbilical vein endothelial cells (HUVEC). After cleavage of t-PA by plasmin, “single-chain” t-PA (sct-PA) is converted into “two-chain” t-PA (tct-PA), which differs from the former in a number of respects. We compared binding of sct-PA and tct-PA to the surface of HUVEC. Removal of t-PA bound to HUVEC by a mild treatment with acid and a subsequent quantification of eluted t-PA both by activity- and immunoradiometric assays revealed that, at concentrations between 10 and 500 nM, HUVEC bind about 3-4 times more sct-PA than tct-PA. At these concentrations, both sct-PA and tct-PA remain active when bound to HUVEC. Mutual competition experiments showed that sct-PA and tct-PA can virtually fully inhibit binding of each other to HUVEC, but that an about twofold higher concentration of tct-PA is required to prevent halfmaximal binding of sct-PA than visa versa. These results demonstrate that sct-PA and tct-PA bind with different affinities to the same binding sites on HUVEC.
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Kobel, Susanne, Sarah Kettner, Nanette Erkelenz, Dorothea Kesztyüs, and Jürgen M. Steinacker. "Effects of Physical Education on Objectively Determined Physical Activity in Primary School Children—Which Proportioning Is Best?" Journal of Teaching in Physical Education 34, no. 3 (July 2015): 537–47. http://dx.doi.org/10.1123/jtpe.2014-0141.
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Physical Education (PE) can foster regular physical activity (PA) in children. However, children engage in insufficient moderate to vigorous PA (MVPA) during PE. This study objectively investigated MVPA of children during a single, compared with double PE-period. In 294 children (7.1 ± 0.7 years) PA was objectively assessed. PE periods were determined and PA was individually calculated. Children spent 8.5 ± 7.3 minutes of each 45 minutes PE lesson in MVPA. Boys were significantly more active than girls (p ≤ .01). All children participated in 135 minutes PE/week, 32.7% were scheduled one double and one single PE-period. Children, with a double PE-period and one single lesson engaged in significantly less MVPA than children, who had three single periods of PE (6.7 ± 6.9 minutes/45 minutes vs. 9.4 ± 7.4 minutes/45 minutes, respectively; p ≤ .01) In conclusion, single periods of PE seem to be more effective in getting primary school children to engage in more MVPA than one double period per week.
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Jørgensen, Maja, Malou Philips, Sixtus Thorsen, Johan Selmer, and Jesper Zeuthen. "Plasminogen Activator Inhibitor-1 Is the Primary Inhibitor of Tissue-Type Plasminogen Activator in Pregnancy Plasma." Thrombosis and Haemostasis 58, no. 03 (1987): 872–78. http://dx.doi.org/10.1055/s-0038-1646006.
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SummaryThe aim of the present work was to clarify to what extent plasminogen activator inhibitor-1 (PAI-1) and plasminogen activator inhibitor-2 (PAI-2) contribute to the increase in plasma inhibition of tissue-type plasminogen activator (t-PA) observed during pregnancy. It was demonstrated that a monoclonal antibody against PAI-1 almost completely quenched inhibition of single-chain t-PA and most of the inhibition of two-chain t-PA in plasma during the third trimester of piegnancy. The remaining inhibition of two-chain t-PA was to a great extent abolished by a PAI-2 antibody. The second order rate constant (k1) for inhibition of single-chain t-PA by the inhibitor neutralized by the PAI-1 antibody was about 4.8 · 106 M-1 · s-1. The conversion of singlechain t-PA to the two-ehain form increased the reaction rate with the inhibitor about 3-fold. These kinetic data are compaiable with those obtained with TAI-l in non-pregnancy plasma oi with purified PAI-1. From the above results it is concluded that PAI-1 is the primary inhibitor of both single-chain and two chain t PA and that PAI-2 is the secondary inhibitor of two-chain t-PA in pregnancy plasma. The concentration of reactive PAI-1 versus gestation age was assayed in plasma from 6 women by binding of PAI-1 to 125I-labelled single-chain t-PA followed by quantitation of the labelled t-PA-PAI-1 complex after separation by SDS- polyacrylamide gel electrophoresis. It was found that the concentration of PAI-1 increased 4 to 8-fold during the gestation period reaching a level of about 1.4 nM at term. Post partum the plasma concentration declined abruptly within 24 h to the level observed in age-matched non-pregnant women.
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Choe, Young-Joe, Hyohyun Nam, and Jung-Dong Park. "A Compact 5 GHz Power Amplifier Using a Spiral Transformer for Enhanced Power Supply Rejection in 180-nm CMOS Technology." Electronics 8, no. 9 (September 17, 2019): 1043. http://dx.doi.org/10.3390/electronics8091043.
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We present a compact 5 GHz, class A power amplifier (PA) applicable for a wireless combo-chip that supports multiple radio systems in 180 nm CMOS technology. The proposed two-stage linear PA consists of a cascode input stage with a transformer-based balun, combined with a balancing capacitor as the load, where the single-ended signal is converted into the balanced output and a second-stage, class A push–pull amplifier with another transformer-based balun, which efficiently combines the output power differentially to drive a single-ended 50 Ω load. The proposed single-ended PA with an internal balanced configuration can achieve a power supply rejection ratio of 9.5 to 65.9 dB at 0.1 to 3.5 GHz, which is around a 12 to 37 dB improvement compared to a conventional single-ended PA with the same power gain. The results show that the proposed PA has a gain of 15.5 dB, an output-referred 1 dB gain compression point of 13 dBm, an output intercept point of 22 dBm with a 5 MHz frequency offset, an output saturated power of 15.4 dBm, and a peak power-added efficiency of 15%. The implemented PA consumes a DC current of 72 mA under 1.8 V supply. The core chip size is 0.65 mm2 without pads.
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Murai, Motohiko, Qiao Li, and Junki Funada. "Study on power generation of single Point Absorber Wave Energy Converters (PA-WECs) and arrays of PA-WECs." Renewable Energy 164 (February 2021): 1121–32. http://dx.doi.org/10.1016/j.renene.2020.08.124.
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Okada, K., H. Fukao, H. Tanaka, S. Ueshima, and O. Matsuo. "Purification and characterization of a plasma factor which cleaves single-chain form of t-PA and u-PA." Thrombosis Research 57 (January 1990): 27–43. http://dx.doi.org/10.1016/0049-3848(90)90376-n.
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Spriggs, DJ, JM Stassen, Y. Hashimoto, and D. Collen. "Thrombolytic properties of human tissue-type plasminogen activator, single-chain urokinase-type plasminogen activator, and synergistic combinations in venous thrombosis models in dogs and rabbits." Blood 73, no. 5 (April 1, 1989): 1207–12. http://dx.doi.org/10.1182/blood.v73.5.1207.1207.
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Abstract Thrombolysis with single and combined four-hour intravenous (IV) infusions of recombinant tissue-type plasminogen activator (rt-PA), recombinant single-chain urokinase-type plasminogen activator of 54,000 molecular weight (mol wt) (rscu-PA), and rscu-PA-32 kD, an rscu-PA derivative of 32,000 mol wt was studied in a femoral vein thrombosis model in the dog and in a jugular vein thrombosis model in the rabbit. In both species, the dose-response curves were linear, and no systemic activation of the fibrinolytic system or fibrinogen breakdown was observed. The steady-state levels of rt-PA-, rscu-PA-, and rscu-PA-32 kD-related antigens in plasma were proportional to the infusion rates. In the dog model, 25% lysis was obtained with 0.11 mg/kg rt-PA, 0.8 mg/kg rscu-PA, and 0.37 mg/kg rscu-PA-32 kD. Combinations of rt-PA and rscu-PA were 2.6 times more active (P less than .005) than anticipated on the basis of their pharmacologic additive effects, whereas combinations of rt-PA and rscu-PA-32 kD were 2.7 times more active (P less than .05). In the rabbit model, 25% lysis was obtained with 0.24 mg/kg rt-PA, 0.75 mg/kg rscu-PA, and 1.25 mg/kg rscu-PA-32 kD. Combinations of rt-PA and rscu-PA have a fivefold synergistic interaction, but surprisingly no synergism was observed between rt-PA and rscu-PA-32 kD. This study shows that synergism between rt-PA and rscu-PA occurs both in rabbits and dogs in a relatively narrow concentration range that allows a fractional reduction of the total equipotent dose by a factor of 2.5-fold to fivefold. Combination therapy is not associated with systemic fibrinolytic activation. This range of synergistic interaction, although limited, may be useful in devising the best thrombolytic therapy for patients with thromboembolic disease.
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Spriggs, DJ, JM Stassen, Y. Hashimoto, and D. Collen. "Thrombolytic properties of human tissue-type plasminogen activator, single-chain urokinase-type plasminogen activator, and synergistic combinations in venous thrombosis models in dogs and rabbits." Blood 73, no. 5 (April 1, 1989): 1207–12. http://dx.doi.org/10.1182/blood.v73.5.1207.bloodjournal7351207.
Full textAbstract:
Thrombolysis with single and combined four-hour intravenous (IV) infusions of recombinant tissue-type plasminogen activator (rt-PA), recombinant single-chain urokinase-type plasminogen activator of 54,000 molecular weight (mol wt) (rscu-PA), and rscu-PA-32 kD, an rscu-PA derivative of 32,000 mol wt was studied in a femoral vein thrombosis model in the dog and in a jugular vein thrombosis model in the rabbit. In both species, the dose-response curves were linear, and no systemic activation of the fibrinolytic system or fibrinogen breakdown was observed. The steady-state levels of rt-PA-, rscu-PA-, and rscu-PA-32 kD-related antigens in plasma were proportional to the infusion rates. In the dog model, 25% lysis was obtained with 0.11 mg/kg rt-PA, 0.8 mg/kg rscu-PA, and 0.37 mg/kg rscu-PA-32 kD. Combinations of rt-PA and rscu-PA were 2.6 times more active (P less than .005) than anticipated on the basis of their pharmacologic additive effects, whereas combinations of rt-PA and rscu-PA-32 kD were 2.7 times more active (P less than .05). In the rabbit model, 25% lysis was obtained with 0.24 mg/kg rt-PA, 0.75 mg/kg rscu-PA, and 1.25 mg/kg rscu-PA-32 kD. Combinations of rt-PA and rscu-PA have a fivefold synergistic interaction, but surprisingly no synergism was observed between rt-PA and rscu-PA-32 kD. This study shows that synergism between rt-PA and rscu-PA occurs both in rabbits and dogs in a relatively narrow concentration range that allows a fractional reduction of the total equipotent dose by a factor of 2.5-fold to fivefold. Combination therapy is not associated with systemic fibrinolytic activation. This range of synergistic interaction, although limited, may be useful in devising the best thrombolytic therapy for patients with thromboembolic disease.
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Waller, Robert, Anne Smith, Helen Slater, Peter O’Sullivan, Darren Beales, Joanne McVeigh, and Leon Straker. "Associations of physical activity or sedentary behaviour with pain sensitivity in young adults of the Raine Study." Scandinavian Journal of Pain 19, no. 4 (October 25, 2019): 679–91. http://dx.doi.org/10.1515/sjpain-2019-0038.
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Abstract Background and aims There is high level evidence for physical activity (PA) improving outcomes in persistent pain disorders and one of the mechanisms proposed is the effect of exercise on central nociceptive modulation. Although laboratory studies and small field intervention studies suggest associations between physical activity and pain sensitivity, the association of objectively measured, habitual PA and sedentary behaviour (SB) with pain sensitivity requires further investigation. Current evidence suggests PA typically lowers pain sensitivity in people without pain or with single-site pain, whereas PA is frequently associated with an increase in pain sensitivity for those with multisite pain. The aim of this study was to explore the relationships of PA and SB with pain sensitivity measured by pressure pain thresholds and cold pain thresholds, considering the presence of single-site and multisite pain and controlling for potential confounders. Methods Participants from the Western Australian Pregnancy Cohort (Raine) Study (n = 714) provided data at age 22-years. PA and SB were measured via accelerometry over a 7-day period. Pain sensitivity was measured using pressure pain threshold (4 sites) and cold pain threshold (wrist). Participants were grouped by number of pain areas into “No pain areas” (n = 438), “Single-site pain” (n = 113) and “Multisite pain” (n = 163) groups. The association of PA and SB variables with pain sensitivity was tested separately within each pain group by multivariable regression, adjusting for potential confounders. Results For those with “Single-site pain”, higher levels (>13 min/day) of moderate-vigorous PA in ≥10 min bouts was associated with more pressure pain sensitivity (p = 0.035). Those with “Multisite pain” displayed increased cold pain sensitivity with greater amounts of vigorous PA (p = 0.011). Those with “No pain areas” displayed increased cold pain sensitivity with decreasing breaks from sedentary time (p = 0.046). Conclusions This study was a comprehensive investigation of a community-based sample of young adults with “No pain areas”, “Single-site pain” and “Multisite pain” and suggests some associations of measures of PA and SB with pain sensitivity. Implications The findings suggest that the pattern of accumulation of PA and SB may be important to inform improved clinical management of musculoskeletal pain disorders. This study provides a baseline for follow-up studies using the Raine Study cohort. Future research should consider temporal influences of PA and SB on pain sensitivity, pain experience and consider using a broader range of pain sensitivity measures.
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Waware, Umesh Somaji, Ravi Arukula, A. M. S. Hamouda, and Peter Kasak. "Electrochemical and X-ray photoelectron spectroscopic investigations of conductive polymers." Ionics 26, no. 2 (November 4, 2019): 831–38. http://dx.doi.org/10.1007/s11581-019-03250-8.
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Abstract We report the synthesis of high soluble poly(aniline-co-o-hydroxyaniline) copolymers with varying the amount of o-hydroxyaniline (20, 40, 60, and 80 %) and referred as PA-co-o-HA20, PA-co-o-HA40, PA-co-o-HA60, and PA-co-o-HA80 respectively. The chemical and structural composition of the polymers and copolymers were determined by XPS, UV–Vis, and FE-SEM analysis. Electrochemical studies of the as-prepared polymers showed two single-electron oxidations and two single-electron reductions reversibly at various scan rates ranging from 20 to 50 mV and results reveals that the current density of the copolymer was lesser than the conventional polyaniline (PA). This is due to increasing the hydroxyl (-OH) branching on the polymer backbone in the polymer chain. The current density decreases from PA-co-o-HA20 to PA-co-o-HA80 by increasing the weight percentage of o-hydroxyaniline in the polymeric backbone.
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Wentzel, Andreas, Shinichi Hori, Makoto Hayakawa, Kazuaki Kunihiro, and Wolfgang Heinrich. "Digital PA with voltage-mode topology using envelope delta-sigma modulation." International Journal of Microwave and Wireless Technologies 5, no. 3 (June 2013): 285–92. http://dx.doi.org/10.1017/s1759078713000457.
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This paper reports on digital transmitter architecture for the 450 MHz band using an envelope delta-sigma modulator realized in CMOS and a voltage-mode class-S (VMCS) power amplifier (PA) based on GaN monolithic microwave integrated circuits (MMICs). The class-S PA is characterized for narrowband single-tone signals and a single- as well as a four-carrier downlink wideband code division multiple access (WCDMA) signal with a peak-to-average power ratio of 7.5 dB. Using single-tone excitation the PA shows a maximum drain efficiency of 86% and a peak output power of 4.4 W. At 6 and 10 dB back-off, 59 and 36% efficiency are achieved, respectively. With the single- and four-carrier WCDMA input signals maximum drain efficiencies of 64 and 53% are reached, respectively, and peak output power is 0.7 W. The adjacent channel leakage ratio shows values of about −34 dBc (5 MHz) and −38 dBc (10 MHz) for single-carrier WCDMA excitation. This is the first complete VMCS PA chain characterized with standard communication signals.
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Nikolic, Pantelija, S. S. Vujatovic, T. Ivetic, M. V. Nikolic, O. Cvetkovic, O. S. Aleksic, V. Blagojevic, G. Brankovic, and N. Nikolic. "Thermal diffusivity of single crystal Bi0.9Sb0.1." Science of Sintering 42, no. 1 (2010): 45–50. http://dx.doi.org/10.2298/sos1001045n.
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A single crystal Bi0.9Sb0.1 ingot was synthesized using the Bridgman technique. Thermal diffusivity and electronic transport properties of single crystal cleaved plates (00l) were determined from PA photoacoustic phase and amplitude spectra obtained using the photoacoustic method with a transmission detection configuration. Both the PA phase and amplitude were measured versus the modulation frequency and numerically analyzed. EDS analyses done to determine chemical composition of the studied samples as well as to check sample homogeneity. Hall effect measurements data were used for the photoacustic measurements.
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Masuda, Kazumi, Tatsuya Hori, Kai Tanabe, Yutaka Kano, Aki Hirayama, and Sohji Nagase. "Proanthocyanidin promotes free radical-scavenging activity in muscle tissues and plasma." Applied Physiology, Nutrition, and Metabolism 32, no. 6 (December 2007): 1097–104. http://dx.doi.org/10.1139/h07-073.
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The present study was carried out to clarify the effect of oral administration of proanthocyanidin (PA) on radical-scavenging activity in muscle and plasma using electron spin resonance (ESR). Eight-week-old male Wistar rats were orally administered with 3 doses per day of 1 mL of 0.05% (PA0.05), 0.5% (PA0.5) or 5% (PA5) PA for 1 week. Control animals received the same volume of distilled water. We also examined the effect of a single dose of 0.5% PA. Blood and muscle were collected from rats 1 h after the final administration. Scavenging activity against superoxide anions in the plasma and m. soleus (Sol), m. plantaris (Pla), deep and surface areas of the m. gastrocnemius (GasD and GasS, respectively) and myocardium (Hrt) was determined using ESR with the spin trap, 5,5-dimethyl-1-pyrroline-N-oxide The scavenging activity in plasma for all groups given PA was 34%–44% higher than the control (p < 0.05). The scavenging activity in Hrt, Sol and GasD increased by up to 50% compared with the control and tended to increase depending on the dose of PA (p < 0.05). The impact of a single dose of PA was undetectable in all tissues. These results suggested that 1 week of oral PA improves the radical-scavenging activity in both plasma and muscle, especially in highly oxidative muscle. A single dose of PA was insufficient to improve the antioxidative capacity of muscle tissues.
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de Munk, Gerard A. W., Eleonore Groeneveld, and Dingeman C. Rijken. "Comparison of the In Vitro Fibrinolytic Activities of Low and High Molecular Weight Single-Chain Urokinase-Type Plasminogen Activator." Thrombosis and Haemostasis 70, no. 03 (1993): 481–85. http://dx.doi.org/10.1055/s-0038-1649609.
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SummaryThe fibrinolytic activity of low molecular weight (LMW) single-chain urokinase-type plasminogen activator (scu-PA) lacking the epidermal growth factor domain and the kringle domain was compared with the activity of high molecular weight (HMW) scu-PA. LMW scu-PA was 1-5 times less active than HMW scu-PA in a fibrin plate method, in a purified fibrin clot lysis assay and in a plasma clot lysis assay. Time course experiments in a chromogenic plasminogen activator assay suggested that LMW scu-PA was less sensitive to activation by plasmin than HMW scu-PA. This was confirmed in a scu-PA activation test, which showed that at a concentration of 40 IU/ml LMW scu-PA required a three-fold higher plasmin concentration for 50% activation in 20 min than did HMW scu-PA. Kinetic experiments in the presence of 0.1 M NaCl showed non-standard Michaelis-Menten kinetics for the activation by plasmin of both HMW and LMW scu-PA. In contrast, standard kinetics was observed at 0.15 M NaCl, showing a 2.6-fold lower catalytic efficiency for LMW scu-PA than for HMW scu-PA. It is concluded that the plasmin activation of LMW scu-PA is about three times slower than the activation of HMW scu-PA. This explains, at least partially, the lower fibrinolytic activity of LMW scu-PA in comparison with HMW scu-PA.
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Hatamoto, Yoichi, Rie Takae, Ryoma Goya, Eichi Yoshimura, Yasuki Higaki, and Hiroaki Tanaka. "Effects of Different Physical Activity Levels during a Single Day on Energy Intake, Appetite, and Energy Balance: A Preliminary Study." Nutrients 11, no. 3 (March 23, 2019): 690. http://dx.doi.org/10.3390/nu11030690.
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We aimed to investigate the effects of a wide range of daily physical activity (PA) levels on energy balance (EB), energy intake (EI), and appetite. Nine young men completed three different PA levels in a metabolic chamber in a random order: (1) no exercise (Low-PA); (2) 25 min walking seven times (Mid-PA); and (3) 25 min running seven times (High-PA) within a 24 h period. Interval exercise (25 min exercise and 35 min rest) was performed three times in the morning and four times in the afternoon. The exercise intensities were 21.6% and 53.7% V ˙ O2 peak for the Mid-PA and High-PA days, respectively. Participants were served three standardized meals and a buffet for dinner. The 24 h EB was calculated as 24 h energy expenditure (EE) minus 24 h EI. The 24 h EEs for the Low-PA, Mid-PA, and High-PA days were 1907 ± 200, 2232 ± 240, and 3224 ± 426 kcal, respectively, with significant differences observed among the three conditions (p < 0.01 for Low-PA vs. Mid-PA, Low-PA vs. High-PA, and Mid-PA vs. High-PA, respectively). The 24 h EIs for the Low-PA, Mid-PA, and High-PA days were 3232 ± 528, 2991 ± 617, and 3337 ± 684 kcal, and were unaffected by PA levels (p = 0.115). The 24 h EBs were 1324 ± 441 kcal (Low-PA), 759 ± 543 kcal (Mid-PA), and 113 ± 430 kcal (High-PA), with significant differences observed between Low-PA vs. Mid-PA (p = 0.0496), Low-PA vs. High-PA (p ≤ 0.01), and Mid-PA vs. High-PA (p = 0.017) conditions. The EB in the Low-PA group was the highest of the three conditions. Appetite perception did not differ among the study days, however there was an interaction trend (p = 0.078, time × condition). Thus, significantly different daily PA did not affect 24 h EI, however markedly affected 24 h EB, implying that EB is not automatically matched during a single day.
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Darras, V., M. Thienpont, D. C. Stump, and D. Collen. "Measurement of Urokinase-Type Plasminogen Activator (u-PA) with an Enzyme-Linked Immunosorbent Assay (ELISA) Based on Three Murine Monoclonal Antibodies." Thrombosis and Haemostasis 56, no. 03 (1986): 411–14. http://dx.doi.org/10.1055/s-0038-1661693.
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SummaryAn enzyme-linked immunosorbent assay (ELISA) for the measurement of urokinase-type plasminogen activator (u-PA) was developed. Three murine monoclonal antibodies to single chain urokinase-type plasminogen activator (scu-PA) were isolated and shown to react with non-overlapping epitopes in scu-PA. Two of the three antibodies were coated onto microtiter plates and bound u-PA was quantitated with the third antibody conjugated to horseradish peroxidase. The assay was equally sensitive to Mr 54,000 u-PA in the single chain or two-chain form but did not respond to Mr 33,000 urokinase. The lower limit of sensitivity of the assay was 0.1 ng/ml in buffer and 1 ng/ml in plasma. Coefficients of variation of the assay at physiological levels of u-PA were 6.5 percent within assays and 13 percent between assays. The level of u-PA in normal resting plasma was 1.9 ± 0.66 ng/ml (mean ± SD, n = 54). The assay can be performed within one working day and provides an efficient, reproducible, and stable means for the measurement of u-PA in biological fluids. As such it may facilitate physiological and pharmacological studies of urokinase-type plasminogen activators in man.
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Collen, Desire. "Fibrin-specific thrombolysis with tissue-type plasminogen activator (t-PA) and single-chain urokinase-type plasminogen activator (scu-PA)." Atherosclerosis 70, no. 1-2 (March 1988): 188–89. http://dx.doi.org/10.1016/0021-9150(88)90119-0.
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Huisman, L. G. M., J. M. T. van Griensven, and C. Kluft. "On the Role of C1-Inhibitor as Inhibitor of Tissue-type Plasminogen Activator in Human Plasma." Thrombosis and Haemostasis 73, no. 03 (1995): 466–71. http://dx.doi.org/10.1055/s-0038-1653798.
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SummaryAn enzyme immuno assay was developed to measure complexes of tissue-type plasminogen activator (t-PA) with C1-inhibitor in order to study the role of C1-inhibitor as an inhibitor of t-PA in plasma. In vitro experiments with melanoma and recombinant t-PA learned that purified C1-inhibitor reacts with both single chain t-PA and two chain t-PA. The rate constants ranged from 3.0 to 5.2 M-1s-1 In plasma, melanoma and recombinant two chain t-PA were hardly inhibited by C1-inhibitor, in contrast to melanoma and recombinant single chain t-PA which were inhibited to the same extent by endogenous C1-inhibitor as they were by purified C1-inhibitor. In vivo, t-PA/C1-inhibitor complex could be measured in plasma in a few cases in healthy volunteers (0.62 ± 0.43 ng/ml t-PA equivalents), after exercise (0.84 ± 0.25 ng/ml t-PA equivalents) and after a desmopressin infusion (0.26 ± 0.04 ng/ml t-PA equivalents). However, t-PA/C1-inhibitor complex was found in plasma in all cases after venous occlusion (1.7 ± 0.5 ng/ml t-PA equivalents), in peritoneal fluid from patients suffering from peritoneal inflammatory disease (2.2 ± 1.3 ng/ml t-PA equivalents) and in plasma from healthy volunteers during a t-PA infusion (27.7 ± 18.5 ng/ml t-PA equivalents at peak level). In the last case, about 8 % of the infused dose of recombinant t-PA (alteplase) was inhibited by C1-inhibitor at peak level. The half-life (t1/2α) of t-PA antigen in plasma was found not to be altered when t-PA was inhibited by C1-inhibitor (4.0 min and 4.2 min, respectively). Thus, in vivo, t-PA/C1-inhibitor complex is mostly present when t-PA escapes rapid liver clearance and accumulates in one place (e.g. during venous occlusion or in peritoneal fluid) or when it circulates in high concentrations (e.g. during t-PA infusion).
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Piszcz, Michał, Oihane Garcia-Calvo, Uxue Oteo, Juan M. Lopez del Amo, Chunmei Li, Lide M. Rodriguez-Martinez, Hicham Ben Youcef, Nerea Lago, Jörg Thielen, and Michel Armand. "New Single Ion Conducting Blend Based on PEO and PA-LiTFSI." Electrochimica Acta 255 (November 2017): 48–54. http://dx.doi.org/10.1016/j.electacta.2017.09.139.
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Corti, Angelo, Maria Luisa Nolli, and Giovanni Cassani. "Differential Detection of Single-Chain and Two-Chain Urokinase-Type Plasminogen Activator by a New Immunoadsorbent-Amidolytic Assay (IAA)." Thrombosis and Haemostasis 56, no. 03 (1986): 407–10. http://dx.doi.org/10.1055/s-0038-1661692.
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SummaryA new immunoadsorbent-amidolytic assay (IAA) for the specific differential detection of two-chain urokinase-type plasminogen activator (tcu-PA) and its single-chain precursor (scu-PA) in cell culture supernatants has been developed. The assay combines the selectivity of immunoassays with the specificity of enzyme activity assays exploiting both the antigenic and enzymatic properties of the two proteins. tcu-PA and scu-PA are selectively immunoadsorbed on the wells of a microtiterplate coated with the monoclonal antibody 5B4 and tested for enzymatic activity before and after activation by plasmin treatment. Both proteins are determined with similar efficiency since overlapping dose-response curves were obtained in the range between 12.5-200 ng/ml. The assay has been used to determine tcu-PA and scu-PA in A431 human epidermoid carcinoma cell supernatants. The analytical recoveries for tcu-PA and scu-PA added to A431 cell supernatants were 95.2% and 96.9% respectively. The intra- and inter-assay variations (CV) were 5.5% and 9.0% for tcu-PA and 9.7% and 9.8% for scu-PA respectively.
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Blanke, Steven R., and David C. Willhite. "Soluble expression and one-step purification of recombinant bacillus anthracis protective antigen." Protein & Peptide Letters 5, no. 5 (October 1998): 273–78. http://dx.doi.org/10.2174/092986650505221111094005.
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Abstract: We have greatly simplified production of the Bacillus anthracis protective antigen (PA), the immunoprotective antigen of the anthrax vaccine. By varying induction conditions, we have expressed stable, soluble PA in E. coli, affinity-tagged to facilitate rapid, single-step purification. Recombinant PA exhibited identical properties to B. anthracis PA. Our approach is an attractive strategy for generating purified vaccine antigens that are difficult to express recombinantly.
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Moreno-Llamas, Antonio, Jesús García-Mayor, and Ernesto De la Cruz-Sánchez. "Concurrent and Convergent Validity of a Single, Brief Question for Physical Activity Assessment." International Journal of Environmental Research and Public Health 17, no. 6 (March 18, 2020): 1989. http://dx.doi.org/10.3390/ijerph17061989.
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An extensive number of self-reported methods for physical activity (PA) measurement are available, including short and long recall questionnaires ranging from a few to tens of questions. Due to the fact that simple, time-saving methods could be more practical and desirable for use in a busy clinical context, as well as in public health surveys, we evaluated how a single-item question might be a useful and cost-effective method for assessing compliance with PA guidelines. Using multiple receiver operating characteristics (ROC), we assessed the classification performance of a single brief question, employing the short version of the International Physical Activity Questionnaire as criterion instrument, in a total of 55,950 people (30,601 women and 25,349 men). Both those who practice PA almost daily and a few times a week presented an upper threshold (1042.5 metabolic equivalent minutes (MET) minutes/week) to the established compliance PA guidelines (600 MET minutes/week) with high specificity and sensitivity, using a sedentary group as reference. Otherwise, the occasionally physically active group did not reach the minimum (349.5 MET minutes/week) and obtained a poorer classification performance. A single brief question is a pragmatic and alternative method for assessment of compliance with PA guidelines.
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Nelles, L., H. R. Lijnen, A. Van Nuffelen, E. Demarsin, and D. Collen. "Characterization of Domain Deletion and/or Duplication Mutants of a Recombinant Chimera of Tissue-Type Plasminogen Activator and Urokinase-Type Plasminogen Activator (rt-PA/u-PAI)." Thrombosis and Haemostasis 64, no. 01 (1990): 053–60. http://dx.doi.org/10.1055/s-0038-1647253.
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SummaryChimeric molecules comprising the A-chain of tissue-type plasminogen activator (t-PA) and the catalytic domain of urokinase-type plasminogen activator (u-PA) have intact enzymatic characteristics of u-PA, but only partial fibrin-binding properties of t-PA (Nelles et al., J Biol Chem 1987; 262: 10855–62). The following domain deletion and/or duplication mutants of such a t-PA/u-PA chimera were constructed, purified and charactertzed: rt-PA-ΔFE∇/u-PA, with deletion of the finger-like (F) and epidermal growth factor-like (E) domains, rt-PA-ΔK1∇K2/u-PA, with kringle 1 (K1) replaced by a second copy of kringle 2 (K2), and rt-PA-ΔFEK1∇K2/u-PA, with F and E domain deletions in rt-PAΔK1∇K2/u-PA.The specific activities on fibrin plates of the single-chain (sc) chimeras ranged between 68,000 IU/mg for rt-PA-ΔK1∇K2/scu-PA and 200,000 IU/mg for rt-PA-ΔFEK1∇K2/scu-PA, as compared to L20,000 IU/mg for rscu-PA. The specific activities of their plasmin-generated two-chain (tc) derivatives ranged between 120,000 IU/mg for rt-PA-ΔK1∇K2/tcu-PA and 240,000 IU/mg for rt-PA-ΔFEK1∇K2/tcu-PA, as compared to 100,000 IU/mg for rtcu-PA. All two-chain chimeras activated plasminogen following Michaelis-Menten kinetics, with catalytic efficiencies between 0.072 μM−1s−1 for rt-PA-ΔK1∇K2/tcu-pA and 0.081 pM−1 s−1 for rt-PA-ΔFEK1∇K2/tcu-PA, as compared to 0.088 μM−1 s−1 for rtcu-PA. CNBr-digested fibrinogen enhanced the initial rate of plasminogen activation by a factor 2.2 to 6.2, as compared to 4.9 for rtcu-PA. The fibrin-affinity of the chimeras decreased in the order rt-PA > rt-PA-ΔK1∇K2/u-PA > u-PA and that for lysine in the order rt-PA-ΔFEK1∇K2/u-PA > > t-PA/u-PA ⩽ st-PA > rt-PA-ΔFE/u-PA > u-PA. All single-chain plasminogen activators caused a time and concentration-dependent clot lysis in an in vitro plasma clot lysis system, with equi-effective doses (causin g 50% clot lysis in 2 h) ranging between 0.53 and 0.90 μg/ml, as compared to 1 .7 μg/ml for rscu-PA, and were associated with comparable residual fibrinogen levels of approximately 80%.Thus, substitution of K1 by a second copy of K2 in the chimeric protein t-PA/u-PA enhances the affinity for both fibrin and lysine significantly and improves the fibrinolytic potency in an in vitro clot lysis system marginally.
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Reed, Justy. "Self-Reported Morningness-Eveningness Related To Positive Affect-Change Associated With A Single Session Of Hatha Yoga." International Journal of Yoga Therapy 24, no. 1 (January 1, 2014): 79–85. http://dx.doi.org/10.17761/ijyt.24.1.w530k7131304q056.
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Objectives: To examine positive affect (PA) responses to a single hatha yoga session compared to a lecture control class and to investigate a potential association between selfreported morningness-eveningness and yoga - related PA change. Method: Participants (Mean age = 28.50 years) in the yoga group (n = 45) and control group (n = 25) completed the revised Morningness-Eveningness Questionnaire (rMEQ) before yoga and lecture (pre) and the Visual Analogue Mood Scale (VAMS) as a measure of PA before and after yoga and lecture (post). Results: Pre-to-post PA change was greater in the yoga group compared to the control (p < 0.001). Analysis of the yoga group VAMS scores revealed a significant rMEQ type (morning, neither, evening) by time (pre to post) interaction (p = 0.03), with greater PA change in evening types compared to morning types (p = 0.01). Conclusions: The results show that a single hatha yoga session improves self-reported PA more than a lecture control and suggest a relationship between self-reported morningness-eveningness and PA responses to hatha yoga. The findings may help yoga practitioners, instructors, and researchers better understand the psychological benefits of yoga. Researchers should consider conducting long-term studies on the association between self-reported morningness- eveningness and affective responses to yoga practice.
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Yang Wang, Chen Wang, Yuanhua Yang, and Baosen Pang. "Effect of Recombinant Single-Chain Urokinase-Type Plasminogen Activator on Experimental Pulmonary Embolism." Clinical and Applied Thrombosis/Hemostasis 16, no. 5 (October 14, 2009): 537–42. http://dx.doi.org/10.1177/1076029609343003.
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To compare experimental canine pulmonary thromboembolism (PTE) treatment effects among domestic recombinant single-chain urokinase-type plasminogen activator (scu-PA), recombinant tissue plasminogen activator (rt-PA), and heparin, we injected autologous blood clots into 19 dogs. Those dogs were divided into 3 groups randomly: (1) scu-PA group (n = 6), (2) rt-PA group (n = 6), and (3) heparin group (n = 7). The measurement of hemodynamics and pulmonary angiography was, respectively, carried out at the time spots of preemboli and postemboli, 2 hours and 3 hours after treatment. Results: (1) An obvious increase in mean pulmonary arterial pressure (mPAP) from preemboli (P < .01) and a decrease in cardiac output (CO; P < .01) after blood clot injection. (2) Intergroup comparisons 2 and 3 hours after treatment: mPAP in scu-PA and rt-PA groups were remarkably lower than those of heparin group (P < .05). (3) Intragroup comparisons after thrombolysis, mPAP declined obviously (P < .01), heparin group saw a further decrease in CO. (4) Pulmonary angiography scoring: decrease in the 2 thrombolytic groups was higher than that of the heparin group. Conclusions: The effects of domestic recombinant scu-PA in experimental PTE resemble that of rt-PA in terms of the improvements of hemodynamics and angiography, better than heparin.
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Dewerchin, M., A.-M. Vandamme, P. Holvoet, F. De Cock, G. Lemmens, H. R. Lijnen, J.-M. Stassen, and D. Collen. "Thrombolytic and Pharmacokinetic Properties of a Recombinant Chimeric Plasminogen Activator Consisting of a Fibrin Fragment D-Dimer Specific Humanized Monoclonal Antibody and a Truncated Single-Chain Urokinase." Thrombosis and Haemostasis 68, no. 02 (1992): 170–79. http://dx.doi.org/10.1055/s-0038-1656344.
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SummaryA recombinant chimeric plasminogen activator consisting of a humanized monoclonal antibody specific for cross-linked human fibrin (MA-15C5Hu) and a 32 kDa single-chain urokinase-type plasminogen activator (scu-PA-32k) comprising amino acids Leu144-Leu411, MA-15C5Hu/scu-PA-32k, was previously found to have a 12-fold higher fibrinolytic potency than recombinant scu-PA-32k towards a human plasma clot in a human plasma milieu in vitro (Vandamme et al., Eur J Biochem 1992; 205: 139–46). Therefore, the thrombolytic and pharmacokinetic properties of MA-15C5Hu/scu-PA-32k were compared with those of recombinant single-chain urokinase-type plasminogen activator (scu-PA) in 3 different venous thrombosis models in vivo. In hamsters with a pulmonary embolus consisting of a human plasma clot, the thrombolytic potency (% lysis per dose in mg/kg administered) of MA-15C5Hu/scu-PA-32k was 23-fold higher than that of scu-PA (p <0.0005). In rabbits with a jugular vein clot prepared from human plasma, the thrombolytic potency of MA-15C5Hu/scu-PA-32k was 11-fold higher than that of scu-PA (p = 0.012). In baboons with an autologous whole blood clot in the femoral vein, the chimera had a 5-fold higher thrombolytic potency than scu-PA. In all three animal species, the clearance of the chimera was 10- to 27-fold reduced as compared to scu-PA. The specific thrombolytic activity (% lysis per µg/ml steady-state plasma u-PA antigen) was increased up to 7-fold with MA-15C5Hu/scu-PA-32k as compared with scu-PA, which is indicative of targeting of the chimera to the clot. No fibrinogen breakdown or α2-antiplasmin depletion was observed during thrombolysis with the chimera.Thus, MA-15C5Hu/scu-PA-32k constitutes a recombinant chimeric plasminogen activator with a significantly enhanced thrombolytic potency in 3 different animal models of venous thrombosis.
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Wang, K., X. H. Sun, Y. Zhang, T. Zhang, Y. Zheng, Y. C. Wei, P. Zhao, et al. "Characterization of cytoplasmic viscosity of hundreds of single tumour cells based on micropipette aspiration." Royal Society Open Science 6, no. 3 (March 2019): 181707. http://dx.doi.org/10.1098/rsos.181707.
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Cytoplasmic viscosity ( μ c ) is a key biomechanical parameter for evaluating the status of cellular cytoskeletons. Previous studies focused on white blood cells, but the data of cytoplasmic viscosity for tumour cells were missing. Tumour cells (H1299, A549 and drug-treated H1299 with compromised cytoskeletons) were aspirated continuously through a micropipette at a pressure of −10 or −5 kPa where aspiration lengths as a function of time were obtained and translated to cytoplasmic viscosity based on a theoretical Newtonian fluid model. Quartile coefficients of dispersion were quantified to evaluate the distributions of cytoplasmic viscosity within the same cell type while neural network-based pattern recognitions were used to classify different cell types based on cytoplasmic viscosity. The single-cell cytoplasmic viscosity with three quartiles and the quartile coefficient of dispersion were quantified as 16.7 Pa s, 42.1 Pa s, 110.3 Pa s and 74% for H1299 cells at −10 kPa ( n cell = 652); 144.8 Pa s, 489.8 Pa s, 1390.7 Pa s, and 81% for A549 cells at −10 kPa ( n cell = 785); 7.1 Pa s, 13.7 Pa s, 31.5 Pa s, and 63% for CD-treated H1299 cells at −10 kPa ( n cell = 651); and 16.9 Pa s, 48.2 Pa s, 150.2 Pa s, and 80% for H1299 cells at −5 kPa ( n cell = 600), respectively. Neural network-based pattern recognition produced successful classification rates of 76.7% for H1299 versus A549, 67.0% for H1299 versus drug-treated H1299 and 50.3% for H1299 at −5 and −10 kPa. Variations of cytoplasmic viscosity were observed within the same cell type and among different cell types, suggesting the potential role of cytoplasmic viscosity in cell status evaluation and cell type classification.
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Hyvärinen, Matti, Sarianna Sipilä, Janne Kulmala, Harto Hakonen, Tuija H. Tammelin, Urho M. Kujala, Vuokko Kovanen, and Eija K. Laakkonen. "Validity and Reliability of a Single Question for Leisure-Time Physical Activity Assessment in Middle-Aged Women." Journal of Aging and Physical Activity 28, no. 2 (April 1, 2020): 231–41. http://dx.doi.org/10.1123/japa.2019-0093.
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Purpose: To investigate the validity and test–retest reliability of a single seven-level scale physical activity assessment question (SR-PA L7) and its three-level categorization (SR-PA C3). Methods: The associations of SR-PA L7 and C3 with accelerometer-measured leisure-time physical activity (ACC-LTPA) and with the results of four different physical performance tests (6-min walk [n = 733], knee extension [n = 695], vertical jump [n = 731], and grip force [n = 780]) were investigated among women aged 47–55 years participating in the Estrogenic Regulation of Muscle Apoptosis study (n = 795). The reliability was studied using Spearman correlations with 4-month test–retest period (n = 152). Results: SR-PA L7 and C3 had low correlations with ACC-LTPA (rs = .105–.337). SR-PA L7, SR-PA C3, and ACC-LTPA explained comparable but small amount of variance of the physical performance test results. The reliability analysis provided moderate agreement (rs = .707 and .622 for SR-PA L7 and C3, respectively). Conclusions: SR-PA L7 and C3 demonstrated limited validity and reasonable repeatability.
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Declerck, Paul J., Leen Van Keer, Maria Verstreken, and Désiré Collen. "An Enzyme-Linked Immunosorbent Assay for Urokinase-Type Plasminogen Activator (u-PA) and Mutants and Chimeras Containing the Serine Protease Domain of u-PA." Thrombosis and Haemostasis 67, no. 01 (1992): 095–100. http://dx.doi.org/10.1055/s-0038-1648387.
Full textAbstract:
SummaryAn enzyme-linked immunosorbent assay (ELISA) for quantitation of natural and recombinant plasminogen activators containing the serine protease domain (B-chain) of urokinase-type plasminogen activator (u-PA) was developed, based on two murine monoclonal antibodies, MA-4D1E8 and MA-2L3, raised against u-PA and reacting with non-overlapping epitopes in the B-chain. MA-4D1E8 was coated on microtiter plates and bound antigen was quantitated with MA-2L3 conjugated with horseradish peroxidase. The intra-assay, inter-assay and inter-dilution coefficients of variation of the assay were 6%, 15% and 9%, respectively. Using recombinant single-chain u-PA (rscu-PA) as a standard, the u-PA-related antigen level in normal human plasma was 1.4 ± 0.6 ng/ml (mean ± SD, n = 27).The ELISA recognized the following compounds with comparable sensitivity: intact scu-PA (amino acids, AA, 1 to 411), scu-PA-32k (AA 144 to 411), a truncated (thrombin-derived) scu-PA comprising A A 157 to 411, and chimeric t-PA/u-PA molecules including t-PA(AA1-263)/scu-PA(AA144-411), t-PA(AA1-274)/scu-PA(AA138-411) and t-PA(AA87-274)/scu-PA(AA138-411). Conversion of single-chain to two-chain forms of u-PA or inhibition of active two-chain forms with plasminogen activator inhibitor-1 or with the active site serine inhibitor phenyl-methyl-sulfonyl fluoride, did not alter the reactivity in the assay. In contrast, inactivation with α2-antiplasmin or with the active site histidine inhibitor Glu-Gly-Arg-CH2Cl resulted in a 3- to 5-fold reduction of the reactivity. When purified scu-PA-32k was added to pooled normal human plasma at final concentrations ranging from 20 to 1,000 ng/ml, recoveries in the ELISA were between 84 and 110%.The assay was successfully applied for the quantitation of pharmacological levels of scu-PA and t-PA(AA87_274)/scu-PA(AA138-411) in plasma during experimental thrombolysis in baboons.Thus the present ELISA, which is specifically dependent on the presence of the serine protease part of u-PA, is useful for measurement of a wide variety of variants and chimeras of u-PA which are presently being developed for improved thrombolytic therapy.
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Chi, Chen, Hirokazu Katsui, Rong Tu, and Takashi Goto. "Microstructure of LiAl5O8 and LiAlO2 Films Prepared by Laser CVD." Key Engineering Materials 616 (June 2014): 223–26. http://dx.doi.org/10.4028/www.scientific.net/kem.616.223.
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α-LiAl5O8, γ-LiAlO2, α-Al2O3and those composite films were prepared on AlN polycrystalline substrates by laser chemical vapor deposition (LCVD), and the effects of total pressure (Ptot) and the molar ratio of Li to Al (RLi/Al) on the morphology and deposition rates were investigated. The typical morphology of single-phase γ-LiAlO2films prepared atRLi/Al> 1.0 andPtot> 400 Pa was granular, whereas γ-LiAlO2films prepared atPtot< 200 Pa and γ-LiAlO2-α-LiAl5O8composite films had pyramidal grains. Single-phase α-LiAl5O8films showed polygonally faceted morphologies. Composite films of α-LiAl5O8and α-Al2O3consisted of carifllower-like and faceted grains. A single-phase γ-LiAlO2film deposited at 200 Pa showed the maximum deposition rate of 48 μm h-1.
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Lijnen, HR, B. Van Hoef, F. De Cock, and D. Collen. "The mechanism of plasminogen activation and fibrin dissolution by single chain urokinase-type plasminogen activator in a plasma milieu in vitro." Blood 73, no. 7 (May 15, 1989): 1864–72. http://dx.doi.org/10.1182/blood.v73.7.1864.1864.
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Abstract The relative contribution of several mechanisms to plasminogen activation and fibrin dissolution by urokinase-type plasminogen activator (u-PA) in vitro was quantitated. The activation of plasminogen by recombinant single chain u-PA (rscu-PA), by its two chain derivative (rtcu-PA) and by a plasmin-resistant mutant, rscu-PA- Glu158, obeys Michaelis-Menten kinetics with catalytic efficiencies of 0.00064, 0.046, and 0.00005 L/mumol.s for native plasminogen (Glu- plasminogen) and of 0.0061, 1.21, and 0.0004 L/mumol.s for partially degraded plasminogen (Lys-plasminogen). In a purified system consisting of a fibrin clot submerged in a plasminogen solution, the equi- effective doses (50% lysis in one hour) for rscu-PA, rtcu-PA, and rscu- PA-Glu158 were 16, 6.5, and 32,000 ng/mL for Glu-plasminogen and two- to fourfold lower for Lys-plasminogen. In a plasma milieu, 50% lysis in two hours was obtained for a plasma clot with 2.1 micrograms/mL rscu- PA, 0.5 micrograms/mL rtcu-PA, and greater than 200 micrograms/mL rscu- PA-Glu158 and for a purified fibrin clot with 1.3 micrograms/mL rscu-PA and 0.27 microgram/mL rtcu-PA. After predigestion of a purified fibrin clot with plasmin, the apparent potency of rscu-PA and rtcu-PA increased by 40% and 20%, respectively. In conclusion, rscu-PA has an intrinsic plasminogen activating potential that is only about 1% of that of rtcu-PA and that is 13 times higher than that of rscu-PA- Glu158. Conformational transition of Glu-plasminogen to Lys-plasminogen enhances its sensitivity to activation by all u-PA moieties ten- to 20- fold. Predigestion of fibrin clots with associated increased binding of plasminogen results in a minor apparent increase of the fibrinolytic potency of rscu-PA and rtcu-PA. The relative fibrinolytic potency of rtcu-PA is two to three orders of magnitude higher than that of rscu-PA- Glu158 but only two- to five-fold higher than that of rscu-PA, both in purified systems and in a plasma milieu. These results indicate that conversion of rscu-PA to rtcu-PA constitutes the primary mechanism of fibrin dissolution.
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Lijnen, HR, B. Van Hoef, F. De Cock, and D. Collen. "The mechanism of plasminogen activation and fibrin dissolution by single chain urokinase-type plasminogen activator in a plasma milieu in vitro." Blood 73, no. 7 (May 15, 1989): 1864–72. http://dx.doi.org/10.1182/blood.v73.7.1864.bloodjournal7371864.
Full textAbstract:
The relative contribution of several mechanisms to plasminogen activation and fibrin dissolution by urokinase-type plasminogen activator (u-PA) in vitro was quantitated. The activation of plasminogen by recombinant single chain u-PA (rscu-PA), by its two chain derivative (rtcu-PA) and by a plasmin-resistant mutant, rscu-PA- Glu158, obeys Michaelis-Menten kinetics with catalytic efficiencies of 0.00064, 0.046, and 0.00005 L/mumol.s for native plasminogen (Glu- plasminogen) and of 0.0061, 1.21, and 0.0004 L/mumol.s for partially degraded plasminogen (Lys-plasminogen). In a purified system consisting of a fibrin clot submerged in a plasminogen solution, the equi- effective doses (50% lysis in one hour) for rscu-PA, rtcu-PA, and rscu- PA-Glu158 were 16, 6.5, and 32,000 ng/mL for Glu-plasminogen and two- to fourfold lower for Lys-plasminogen. In a plasma milieu, 50% lysis in two hours was obtained for a plasma clot with 2.1 micrograms/mL rscu- PA, 0.5 micrograms/mL rtcu-PA, and greater than 200 micrograms/mL rscu- PA-Glu158 and for a purified fibrin clot with 1.3 micrograms/mL rscu-PA and 0.27 microgram/mL rtcu-PA. After predigestion of a purified fibrin clot with plasmin, the apparent potency of rscu-PA and rtcu-PA increased by 40% and 20%, respectively. In conclusion, rscu-PA has an intrinsic plasminogen activating potential that is only about 1% of that of rtcu-PA and that is 13 times higher than that of rscu-PA- Glu158. Conformational transition of Glu-plasminogen to Lys-plasminogen enhances its sensitivity to activation by all u-PA moieties ten- to 20- fold. Predigestion of fibrin clots with associated increased binding of plasminogen results in a minor apparent increase of the fibrinolytic potency of rscu-PA and rtcu-PA. The relative fibrinolytic potency of rtcu-PA is two to three orders of magnitude higher than that of rscu-PA- Glu158 but only two- to five-fold higher than that of rscu-PA, both in purified systems and in a plasma milieu. These results indicate that conversion of rscu-PA to rtcu-PA constitutes the primary mechanism of fibrin dissolution.
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Iannotti, Ronald J., James F. Sallis, Rusan Chen, Shelia L. Broyles, John P. Elder, and Philip R. Nader. "Prospective Analyses of Relationships Between Mothers’ and Children’s Physical Activity." Journal of Physical Activity and Health 2, no. 1 (January 2005): 16–34. http://dx.doi.org/10.1123/jpah.2.1.16.
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Background:Longitudinal patterns in the development of physical activity (PA) and potential causal relationships between parent and child PA are examined.Methods:Autoregressive models were used to examine bidirectional prospective paths between parent and child PA in a longitudinal sample of 351 Anglo and Mexican American families. PA was assessed independently in children and parents over a 13-y period.Results:There was little evidence for a causal path from mother PA to child PA.Conclusions:Modeling does not appear to be the primary mechanism by which parents influence children’s PA behavior. Studies examining relations between parent and child behaviors should not rely on a single respondent for assessing both parent and child PA or on cross-sectional correlational data to make unidirectional causal inferences about determinants of child PA.
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Jiang, Y., R. Pannell, JN Liu, and V. Gurewich. "Evidence for a novel binding protein to urokinase-type plasminogen activator in platelet membranes." Blood 87, no. 7 (April 1, 1996): 2775–81. http://dx.doi.org/10.1182/blood.v87.7.2775.bloodjournal8772775.
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Endogenous urokinase-type plasminogen activator (u-PA) has been identified in platelet membrane, and platelets have been shown to take up exogenous high molecular weight u-PA from the ambient medium. In this report, the mechanism of the association of u-PA with platelets was investigated using recombinant, single chain u-PA. When gel filtered human platelets were incubated with radiolabeled u-PA, the u- PA was found to specifically and saturably bind to the resting platelets in a dose-dependent manner. Unlabeled u-PA and the amino terminal fragment of u-PA inhibited 125I-u-PA binding to platelets with a mean IC50 of 65 and 58 nmol/L, respectively. A single saturable binding site in intact resting platelets was found with a mean kd of 43 +/- 25 nmol/L and 2263 +/- 809 sites per platelet. In contrast to resting platelets, 125I-u-PA did not bind to thrombin-induced platelets. Western blotting studies, using a monoclonal or a polyclonal antibody specific for the u-PA cell-surface receptor (u- PAR), failed to show evidence of u-PAR in resting platelets, whereas, u-PAR was found at approximately 54 and approximately 48 kD on U937 monocytes, which served as a positive control. Ligand blotting of platelet membrane and of U937 cell proteins with 125I-u-PA revealed a u-PA binding protein of approximately 70 kD in the platelets and one of approximately 54 kD in the U937 cells. Complexion of u-PA with a platelet membrane protein was also shown by gel filtration of a mixture of u-PA and platelet membrane proteins. A u-PA complex was further shown by enzyme-linked immunosorbent assay when microtiter plates were coated with platelet membrane proteins, and this complex formation was shown to be dose-dependent and saturable with an apparent kd of 17 nmol/L. It was concluded that platelet membrane contains a specific, high affinity u-PA-binding protein that is distinct from u-PAR.
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Fukumoto, Tazuru, Hironobu Umakoshi, Masatoshi Ogata, Maki Yokomoto-Umakoshi, Yayoi Matsuda, Misato Motoya, Hiromi Nagata, et al. "Significance of Discordant Results: between Confirmatory Tests in Diagnosis of Primary Aldosteronism." Journal of the Endocrine Society 5, Supplement_1 (May 1, 2021): A95—A96. http://dx.doi.org/10.1210/jendso/bvab048.191.
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Abstract Context: Current clinical guidelines recommend confirmation of positive result in at least one confirmatory test in the diagnosis of primary aldosteronism (PA). Clinical implication of multiple confirmatory tests has not been established, especially when patients show discordant results. Objective: The aim of the present study was to explore the role of two confirmatory tests in subtype diagnosis of PA. Design: Retrospective cross-sectional study. Setting: The study was conducted at two referral centers. Participants and Method: We identified 360 hypertensive patients who underwent both captopril challenge test (CCT) and saline infusion test (SIT) and exhibited at least one positive result. Among them, we studied 193 patients with PA whose data were available for subtype diagnosis based on adrenal vein sampling (AVS). Main Outcome Measure: The prevalence of bilateral subtype on AVS according to the results of the confirmatory tests. Results: Of patients studied, 127 were positive for both CCT and SIT (double-positive), while 66 were positive for either CCT or SIT (single-positive) (n = 34 and n = 32, respectively). Altogether, 135 were diagnosed with bilateral subtype on AVS. The single-positive patients had milder clinical features of PA than the double-positive patients. The prevalence of bilateral subtype on AVS was significantly higher in the single-positive patients than in the double-positive patients. (63/66 [95.5%] vs. 72/127 [56.7%], P < 0.01). Several clinical parameters were different between CCT single-positive and SIT single-positive patients. Conclusion: Patients with discordant results between CCT and SIT have a high probability of bilateral subtype of PA on AVS.
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Öhman, Juha, Antti Servo, and Olli Heiskanen. "Effect of intrathecal fibrinolytic therapy on clot lysis and vasospasm in patients with aneurysmal subarachnoid hemorrhage." Journal of Neurosurgery 75, no. 2 (August 1991): 197–201. http://dx.doi.org/10.3171/jns.1991.75.2.0197.
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✓ A prospective series of 30 patients with a single, angiographically verified aneurysmal subarachnoid hemorrhage (SAH) was studied for the effect of intrathecal thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA) on outcome, angiographic vasospasm, and computerized tomography (CT) findings after surgery. The patients included fulfilled the following criteria: operation was performed by Day 3 after the hemorrhage, CT showed only blood in the basal cisterns, and the patient had a single aneurysm or multiple aneurysms that could be treated surgically at the same operation. The patients were divided into groups of 10, with patients receiving 3, 10, or 13 mg of rt-PA in a single intracisternal injection at the end of the operation. There were no differences between the treatment groups in overall outcome. One patient from the 3-mg rt-PA group developed a postoperative intracerebral hemorrhage, and one patient from the 10-mg rt-PA group had a postoperative epidural hematoma. There was one death in the 13-mg rt-PA group that was caused by inclusion of a segment of pericallosal artery in the clip. In all treatment groups a reduction was observed in the amount of blood seen on the postoperative CT scans compared to the preoperative CT scans. The reduction in SAH grade between the 10-mg and 13-mg rt-PA groups was significant (p < 0.05). The difference in the severity of angiographic vasospasm between the 3-mg and 13-mg rt-PA groups was also significant (p < 0.05).