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Young KC, Shi GY, Wu DH, Chang LC, Chang BI, Ou CP, Wu HL. Plasminogen activation by streptokinase via a unique mechanism. J Biol Chem 1998; 273:3110-6. [PMID: 9446629 DOI: 10.1074/jbc.273.5.3110] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The mechanism of human plasminogen (HPlg) activation by streptokinase (SK)-type activator was investigated with recombinant truncated SK peptides. An enzyme-substrate intermediate of HPlg.SK. HPlg ternary complex was demonstrated by a sandwich-binding experiment. Formation of the ternary complex was saturable, HPlg-specific, and inhibited by 6-aminocaproic acid. Three interaction sites between SK and HPlg were demonstrated. SK-(220-414) bound to HPlg with two binding sites: one to the micro-HPlg region, the catalytic domain of HPlg, and one to the kringle 1-5 region, with Kd values of 1.50 x 10(-7) and 2.44 x 10(-6) M, respectively. SK-(16-251) bound to a single site on the kringle 1-5 region of HPlg with a Kd of 4.09 x 10(-7) M. SK-(220-414) and SK-(16-251) competed for binding on the same or nearby location on the human kringle 1-5 domain. Combination of SK-(220-414) and SK-(16-251), but not either peptide alone, could effectively activate HPlg. In addition, SK-(16-251) dose-dependently enhanced the activation of HPlg by SK-(16-414), while the HPlg activation by SK-(16-414) was inhibited by SK-(220-414). We conclude that the HPlg that binds to the COOH-terminal domains of SK functions as an enzyme to catalyze the conversion of substrate HPlg that binds to the NH2-terminal domain of SK to human plasmin.
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Sunshine JL, Lewin JS, Wu DH, Miller DA, Findling RL, Manos MJ, Schwartz MA. Functional MR to localize sustained visual attention activation in patients with attention deficit hyperactivity disorder: a pilot study. AJNR Am J Neuroradiol 1997; 18:633-7. [PMID: 9127023 PMCID: PMC8338480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE To evaluate brain control activation in patients with attention deficit hyperactivity disorder (ADHD) and to provide an initial comparison between activated regions in ADHD subjects and those previously localized in an unaffected population. METHODS Ten patients with ADHD underwent imaging with a functional blood oxygen level-dependent MR technique during sustained visual vigilance. Pixel activation was inspected visually and statistical group analysis was performed. RESULTS Activation was seen over the bilateral middle frontal gyri, the superior parietal lobules, and the inferior parietal lobules. The predominant activity occurred in the right middle frontal gyrus. Application of an additional statistical constraint revealed significant activity in the right inferior and left superior parietal lobules. CONCLUSION ADHD patients effectively tolerated the necessary MR imaging constraints despite their difficulty with confinement and immobility. Single-section functional MR imaging revealed activation in brain regions known to be involved in the maintenance of the attention in healthy subjects responding to auditory, tactile, or visual stimulation; additional areas of activity that were identified may represent true abnormal regions in the affected population or artifacts.
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Wu DH, Laidman DL. Isolation of six low molecular weight heat shock proteins and partial characterization of heat shock protein 29 from mung bean hypocotyl. PHYTOCHEMISTRY 1997; 44:985-989. [PMID: 9055444 DOI: 10.1016/s0031-9422(96)00674-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Heat shock protein (HSP29) together with five other low-M(r) HSPs have been isolated from mung bean hypocotyls by preparative continuous elution SDS-PAGE. Autoradiography and immunochemical analysis of 2D electrophoretograms of the radiolabelled HSP29 revealed that it consists of seven isotypes, two of which are constitutive while the other five are heat-inducible. The pI values of the seven isotypes range from 4.6 to 6.6. A monoclonal antibody raised against the HSP29 isolate reacted with six of the seven isotypes. When HSP29 was subjected to partial proteolysis by V8 Staphylococcus aureus protease (EC 3.4.21.19), two fragments of 12 and 17 kDa were identified, neither of which was recognized by the antibody.
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Wu DH, Lewin JS, Duerk JL. Inadequacy of motion correction algorithms in functional MRI: role of susceptibility-induced artifacts. J Magn Reson Imaging 1997; 7:365-70. [PMID: 9090592 DOI: 10.1002/jmri.1880070219] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Functional MR (fMR) has been useful in providing insight into the localization and detection of neural cortical activity. However, patient head motion is inevitable over the course of most fMR experiments. Although methods to align the control and activation fMR images may correct for some of this motional error, they will be incomplete in correcting for those that depend on spatial orientation. MR signal amplitude of structures that lie along air-tissue interfaces, for example, are sensitive to susceptibility errors introduced by their reorientation with respect to the main magnetic field. This analysis, using phantoms, cadaver brain, and volunteers, has shown that this reorientation between control and activation images can create regions of "false activation" that increase in area with rotation. Anatomic regions that are expected to be most affected by these susceptibility-induced magnetic field homogeneity variations are those adjacent to bone or air, such as the mesial and inferior temporal lobes and the inferior and anterior frontal lobes. Interpretation of "activation" in these areas on fMR studies must be performed with careful consideration of this important source of error.
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Booth JC, Wu DH, Qadri SB, Skelton EF, Osofsky MS, Piqué A, Anlage SM. Large Dynamical Fluctuations in the Microwave Conductivity of YBa2Cu3O7- delta above Tc. PHYSICAL REVIEW LETTERS 1996; 77:4438-4441. [PMID: 10062538 DOI: 10.1103/physrevlett.77.4438] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Duerk JL, Lewin JS, Wu DH. Application of keyhole imaging to interventional MRI: a simulation study to predict sequence requirements. J Magn Reson Imaging 1996; 6:918-24. [PMID: 8956138 DOI: 10.1002/jmri.1880060613] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A wide variety of techniques have been proposed recently to improve the temporal resolution of MRI. These include echo-planar imaging methods, wavelet encoding, singular value decomposition encoding, and k-space sharing methods known as "keyhole" imaging. In this work, we use a simulation study to investigate the phase-encoding ordering and data-sharing methods required for the application of keyhole imaging to interventional MRI (I-MRI). The advantages of keyhole imaging over other methods are its simplicity and the use of conventional phase encoding and Fourier transform reconstruction found on virtually all modern MR imagers. Our analysis has predicted that conventional keyhole methods that repeatedly acquire only the center portion of k space, and those that sequentially progress from the center of k space outward, will not meet the combination of temporal and spatial resolution required for tip localization during I-MRI needle insertion. Instead, acquisitions that acquire both high and low k-space data, in ranked order, should provide acceptable tip position and needle width accuracy in both temporal and spatial domains for use in I-MRI.
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Duerk JL, Wu DH, Chung YC, Liang ZP, Lewin JS. A simulation study to assess SVD encoding for interventional MRI: effect of object rotation and needle insertion. J Magn Reson Imaging 1996; 6:957-60. [PMID: 8956146 DOI: 10.1002/jmri.1880060621] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Singular value decomposition (SVD) encoding offers great promise to provide high spatial and temporal resolution required for interventional MRI (I-MRI) (1). This study investigates its efficacy when (a) objects are rotated and (b) a small device (ie, a needle) is moved within anatomic structures. It was found that SVD-encoded MRI is biased toward the reference from which encoding vectors are derived, thus providing a potential limitation under conditions in which the object has undergone significant global change. Reference images with partial device insertion may be needed to accurately resolve the device or track the object motion. Theoretically, the differences between the reference and the object being imaged suggest that SVD encoding is suboptimal (in a minimum mean squared error sense). Other encoding/reconstruction algorithms may come closer to achieving the desired advantages in spatial and temporal fidelity.
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Anlage SM, Mao J, Booth JC, Wu DH, Peng JL. Fluctuations in the microwave conductivity of YBa2Cu3O7- delta single crystals in zero dc magnetic field. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:2792-2796. [PMID: 9983791 DOI: 10.1103/physrevb.53.2792] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Wu DH, Booth JC, Anlage SM. Frequency and field variation of vortex dynamics in YBa2Cu3O7- delta. PHYSICAL REVIEW LETTERS 1995; 75:525-528. [PMID: 10060043 DOI: 10.1103/physrevlett.75.525] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Mao J, Wu DH, Peng JL, Greene RL, Anlage SM. Anisotropic surface impedance of YBa2Cu3O7- delta single crystals. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 51:3316-3319. [PMID: 9979138 DOI: 10.1103/physrevb.51.3316] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Shi GY, Chang BI, Chen SM, Wu DH, Wu HL. Function of streptokinase fragments in plasminogen activation. Biochem J 1994; 304 ( Pt 1):235-41. [PMID: 7998939 PMCID: PMC1137477 DOI: 10.1042/bj3040235] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Several peptide fragments of streptokinase (SK) were prepared by incubating SK with immobilized human plasmin (hPlm) and purified by h.p.l.c. with a reverse-phase phenyl column. The N-terminal sequences, amino acid compositions and molecular masses of these peptide fragments were determined. The SK peptide fragment of 36 kDa consisting of Ser60-Lys387 (SK-p), was the only peptide fragment that could be tightly bound to immobilized hPlm. Another three large SK peptide fragments, SK-m, SK-n and SK-o, with molecular masses of 7 kDa, 18 kDa and 30 kDa, and consisting of Ile1-Lys59, Glu148-Lys333, Ser60-Lys333 respectively, were also obtained from the supernatant of the reaction mixture. The purified SK-p had high affinity with hPlm and could activate human plasminogen (hPlg) with a kPlg one-sixth that of the native SK. SK-o had low affinity with hPlm and could also activate hPlg, although the catalytic constant was less than 1% of the native SK. SK-n, as well as SK-m, which is the N-terminal 59 amino acid peptide of the native SK, had no activator activity. However, SK-m could enhance the activator activity of both SK-o and SK-p and increase their second-order rate constants by two- and six-fold respectively. It was concluded from these studies that (1) SK-o, the Ser60-Lys333 peptide of SK, was essential for minimal SK activator activity, (2) the C-terminal peptide of SK-p, Ala334-Lys387, was essential for high affinity with hPlm, and (3) the N-terminal 59-amino-acid peptide was important in maintaining the proper conformation of SK to have its full activator activity.
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Anlage SM, Wu DH, Mao J, Mao SN, Xi XX, Venkatesan T, Peng JL, Greene RL. Electrodynamics of Nd1.85Ce0.15CuO4: Comparison with Nb and YBa2Cu3O7- delta. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 50:523-535. [PMID: 9974571 DOI: 10.1103/physrevb.50.523] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Wu DH. A review of the safety profile of cefixime. Clin Ther 1993; 15:1108-19. [PMID: 8111808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Data are reviewed for safety from worldwide clinical trials of 4000 patients and postmarketing studies of 38,000 patients treated with cefixime, a broad-spectrum, bactericidal, beta-lactam stable, third-generation cephalosporin. Adverse experiences were similar in adults and children in all groups, with the most frequent side effects being gastrointestinal in nature. The reported frequency of gastrointestinal adverse experiences was higher in patients in US clinical trials when compared with French, German, or Canadian clinical trials or Canadian or US postmarketing studies. The overall incidence of side effects ranged from 2.7% to 48.2%, and the incidence of gastrointestinal events reported in these studies ranged from 1.4% to 38.6%. Patients infrequently discontinued treatment due to adverse events. The design and methods of data collection in US clinical trials may have resulted in higher frequencies of adverse experiences being reported in US trials when compared with the experiences reported in postmarketing studies and in clinical trials conducted outside of the United States. This is because of the more rigorous methodology used to elicit patient reporting of adverse events in US clinical trials compared with the methodology in postmarketing studies and foreign clinical trials.
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Shi GY, Chang BI, Wu DH, Wu HL. Interaction of immobilized human plasminogen and plasmin with streptokinase. Biochem Biophys Res Commun 1993; 195:192-200. [PMID: 8363600 DOI: 10.1006/bbrc.1993.2029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The complex of immobilized human plasminogen (iHPlg) and streptokinase (SK) has a lower catalytic activity in hydrolysis of plasmin-specific substrate S-2251 with a kcat/Km of 0.005 microM-1 x s-1, compared to 0.031 microM-1 x s-1 of immobilized human plasmin (iHPlm) and 0.078 microM-1 x s-1 of HPlm. The SK in the complex could be removed by acid buffer solution, and the iHPlg will remain catalytically active. IHPlm.SK complex could activate bovine plasminogen (BPlg), whereas iHPlg.SK complex could not. IHPlg could be activated by interaction with a combination of SK and HPlg or urokinase. The activated iHPlg.SK complex had the ability to activate BPlg as iHPlm.SK. The reasonable explanation is that iHPlg was converted to iHPlm in reaction with the combination of HPlg and SK. However, iHPlg was converted to a virgin enzyme in reaction with SK alone and could not activate BPlg. A new modified mechanism for the interaction of HPlg or HPlm with SK was proposed.
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Wu DH, Mao J, Mao SN, Peng JL, Xi XX, Venkatesan T, Greene RL, Anlage SM. Temperature Dependence of Penetration Depth and Surface Resistance of Nd1.85Ce0.15CuO4. PHYSICAL REVIEW LETTERS 1993; 70:85-88. [PMID: 10053264 DOI: 10.1103/physrevlett.70.85] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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66
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Wu HL, Wu IS, Fang RY, Hau JS, Wu DH, Chang BI, Lin TM, Shi GY. The binding of plasminogen fragments to cultured human umbilical vein endothelial cells. Biochem Biophys Res Commun 1992; 188:703-11. [PMID: 1445315 DOI: 10.1016/0006-291x(92)91113-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Glu-plasminogen, kringle 1-5, kringle 1-3, and miniplasminogen exhibited strong binding to human umbilical vein endothelial cells (HUVEC). On the other hand, no significant binding was obtained with microplasminogen and kringle 4. Kringle 1-5 and miniplasminogen, which both contained kringle 5, specifically inhibited the binding of plasminogen to HUVEC while kringle 1-3 did not. The results implied plasminogen molecule contained at least two binding sites, with which it interacted HUVEC. The stronger binding site was located in kringle 5 and the weaker one was in kringle 1-3. Kringle 4 and the active site domain exhibited no significant binding to HUVEC. The interaction of plasminogen with HUVEC is mainly through binding site on kringle 5.
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Sridhar S, Maheswaran B, Willemsen BA, Wu DH, Haddon RC. Scaling behavior of the rf vortex penetration depth in an organic superconductor. PHYSICAL REVIEW LETTERS 1992; 68:2220-2223. [PMID: 10045337 DOI: 10.1103/physrevlett.68.2220] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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68
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Wu DH, Sridhar S. Wu and Sridhar reply. PHYSICAL REVIEW LETTERS 1991; 67:1474. [PMID: 10044162 DOI: 10.1103/physrevlett.67.1474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Abstract
The rate of plasmin denaturation was in the order of Lys-plasmin greater than miniplasmin greater than microplasmin. Fibrinogen degradation products (FDP) dose dependently increased the denaturation rate of Lys-plasmin and mini-plasmin with a maximal rate constant at the FDP/plasmin ratio of about 0.5. The denaturation rate constant of microplasmin was not affected. FDP increased the rate of plasmin denaturation was in parallel with its effect on the interaction among kringle domains. Without FDP only trace amounts of plasminogen dimer could be detected by cross-linking with bis-(sulfo-succinimidyl)-suberate followed by SDS gel electrophoresis. In the low concentration of FDP significant amounts of oligomers of Glu-, mini-plasminogens, kringle 1-3 and kringle 1-5 were observed. High concentration of FDP, however, decreased plasminogen oligomer.
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Wu DH. Efficacy and tolerability of cefixime in otitis media. A multicentre study in over 25,000 children. Drugs 1991; 42 Suppl 4:30-2. [PMID: 1725152 DOI: 10.2165/00003495-199100424-00009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A large scale multicentre clinical study was undertaken to assess the efficacy and tolerability of cefixime in the treatment of acute otitis media in children. A total of 25,863 evaluable children with acute otitis media received cefixime 8 mg/kg once daily for at least 10 days. At the end of treatment, 86% of patients were considered to be either cured or improved. These results are consistent with those achieved with cefixime in controlled clinical trials. Adverse effects were reported in 11.5% of patients, but were judged to be related to cefixime therapy in only 9.4% of patients. The results of this study demonstrate that cefixime is an effective and well tolerated treatment for acute otitis media in children.
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Wu HL, Chang BI, Wu DH, Chang LC, Gong CC, Lou KL, Shi GY. Interaction of plasminogen and fibrin in plasminogen activation. J Biol Chem 1990; 265:19658-64. [PMID: 2174048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Glu1-, Lys77-, miniplasminogens, kringle 1-3, kringle 1-5A, and kringle 1-5R were able to bind with fibrin, while microplasminogen and kringle 4 did not bind significantly. Kringle 1-5A, but not kringle 1-3, effectively inhibited the binding of Glu1-, Lys77-, and miniplasminogens with fibrin. Miniplasminogen also inhibited the binding of Glu1-plasminogen with fibrin. The binding of kringle 1-3 with fibrin was blocked by mini- or Glu1-plasminogen. It is therefore evident that there are two fibrin-binding domains in plasminogen and that the one in kringle 5 is of higher affinity than that in kringle 1-3. CNBr cleavage products of fibrinogen effectively enhanced the activation of Glu1-, Lys77-, or miniplasminogens, but not microplasminogen, by tissue-type plasminogen activator. Kringle 1-5, but not kringle 1-3, dose-dependently inhibited the enhancement by fibrinogen degradation products of Glu1-plasminogen activation by the activator. Lysine and epsilon-aminocaproic acid could inhibit the binding of plasminogens and plasminogen derivatives with fibrin and block the enhancement effect of fibrinogen degradation products on plasminogen activation. The data clearly illustrate that the binding of plasminogen with fibrin, mainly determined by kringle 5, is essential for effective activation by tissue-type plasminogen activator. However, the presence of kringle 1-4 in the plasminogen molecule is required for the full enhancing effect since the kcat/Km of miniplasminogen activation in the presence of fibrinogen degradation products was 8.2 microM-1 min-1 which is significantly less than 52.0 microM-1 min-1 of Glu1-plasminogen.
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Wu HL, Chang BI, Wu DH, Chang LC, Gong CC, Lou KL, Shi GY. Interaction of plasminogen and fibrin in plasminogen activation. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(17)45422-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Wu DH, Sridhar S. Pinning forces and lower critical fields in YBa2Cu3Oy crystals: Temperature dependence and anisotropy. PHYSICAL REVIEW LETTERS 1990; 65:2074-2077. [PMID: 10042440 DOI: 10.1103/physrevlett.65.2074] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Shi GY, Change BI, Wu DH, Ha YM, Wu HL. Activation of human and bovine plasminogens by the microplasmin and streptokinase complex. Thromb Res 1990; 58:317-29. [PMID: 2141198 DOI: 10.1016/0049-3848(90)90101-h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Human microplasmin is a catalytically active fragment of human plasmin. It consists of a 31-residue C-terminal peptide derived from the A chain bound through two disulfide bonds to the intact B chain of plasmin. It has similar amidolytic and proteolytic activities as the native human Lys-plasmin on a molar basis. Human microplasmin can form a complex with streptokinase, in a one to one stoichiometry, like the native human Lys-plasmin. The stoichiometric human microplasmin and streptokinase complex is an efficient activator of bovine plasminogen which can not be activated by streptokinase alone. The formation of human microplasmin.streptokinase complex was also directly demonstrated by a gel filtration column chromatography. Moreover, bovine plasminogen can not be activated by a mixture of bovine or porcine microplasmin and streptokinase. The equimolar complex of human microplasmin.streptokinase, human Lys-plasmin.streptokinase, or streptokinase alone has the same activator activity toward human Lys-plasminogen. The human microplasmin.streptokinase complex, however, has a significantly higher activator activity than human Lys-plasmin.streptokinase complex or streptokinase alone toward human Glu-plasminogen. The direct interaction between streptokinase and light chain domain of human plasmin is demonstrated in the complex formation. The difference in the activator activities of plasmins from various animal sources in complex with streptokinase therefore might be due to the difference in the compositions of light chains of plasmins.
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Lund J, Ahlgren R, Wu DH, Kagimoto M, Simpson ER, Waterman MR. Transcriptional regulation of the bovine CYP17 (P-450(17)alpha) gene. Identification of two cAMP regulatory regions lacking the consensus cAMP-responsive element (CRE). J Biol Chem 1990; 265:3304-12. [PMID: 1689300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Regions within the 5'-flanking sequence of the bovine CYP17 (P-450(17)alpha) gene which are required for cAMP-dependent regulation of transcription have been localized by transient transfection of chimeric reporter gene constructs into mouse adrenal tumor Y1 cells. Two sequences have been found which individually confer cAMP responsiveness to reporter genes; they are located at -243/-225 and -80/-40 base pairs (bp). Obvious sequence homology between these two regions is not apparent. Gel shift competition analysis indicates that nuclear protein(s) binding to the -243/-225-bp region can be competed for by the addition of a double-stranded oligonucleotide containing a consensus cAMP-responsive element (CRE) from the human chorionic gonadotropin alpha gene, whereas addition of this CRE does not abolish protein-DNA complexes formed with fragments containing the -80/-40-bp sequence. Gel shift and Southwestern analysis indicate that the -243/-225-bp region of the P-450(17)alpha gene and the CRE both bind a 47-kDa protein and that the CRE binds additional proteins (43 and 68 kDa) not apparently recognized by the -243/-225-bp sequence. Thus cAMP-dependent regulation of the bovine P-450(17)alpha gene appears to involve two independent cis-regulatory regions, neither of which contains a consensus CRE. Based on protein binding analysis, one of these regions (that including -80/-40 bp) is distinct from the consensus CRE while the other (that containing -243/-225 bp) may be related to the consensus CRE.
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Lund J, Ahlgren R, Wu DH, Kagimoto M, Simpson ER, Waterman MR. Transcriptional regulation of the bovine CYP17 (P-450(17)alpha) gene. Identification of two cAMP regulatory regions lacking the consensus cAMP-responsive element (CRE). J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39767-4] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Sridhar S, Wu DH, Kennedy W. Temperature dependence of electrodynamic properties of YBa2Cu3Oy crystals. PHYSICAL REVIEW LETTERS 1989; 63:1873-1876. [PMID: 10040695 DOI: 10.1103/physrevlett.63.1873] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Wu DH, Tavoni A, Garzelli C, Neri R, Vitali C, Bombardieri S. A simple method for the biochemical purification of Ro/SS-A antigen. J Immunol Methods 1989; 121:219-24. [PMID: 2760465 DOI: 10.1016/0022-1759(89)90163-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In the present study, Ro/SS-A antigen has been isolated from human spleen by a two-step procedure. In the first step most of the non-antigenic material was removed by means of ammonium sulphate precipitation and ion exchange chromatography. The final purification was obtained by passing the Ro/SS-A-containing fractions twice through a Mono Q ion exchange fast protein liquid chromatography (FPLC) column. The purified antigen showed identical immunoreactivity with crude material on CIE and was composed of two polypeptides with a molecular weight of approximately 60,000 and 55,000 respectively on SDS-PAGE, both reacting on Western blotting with a panel of anti-Ro/SS-A antisera. This system permits milligrams of highly purified antigen to be obtained from grams of human spleen.
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Vitali C, Giuggioli C, Monti P, Rossi G, Wu DH, d'Ascanio A, Chiellini S, Gabriele M, Bombardieri S. Statistical evaluation of different clinical and serological parameters for the diagnosis of Sjögren's syndrome. Clin Exp Rheumatol 1989; 7:191-5. [PMID: 2736833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The potential value for the diagnosis of Sjögren's syndrome (SS) of 28 clinical and 18 serological parameters was evaluated in 38 patients with primary (1 degree) SS, 29 with rheumatoid arthritis (RA), 30 with systemic lupus erythematosus (SLE), and 22 with mixed cryoglobulinemia (MC), by means of a stepwise discriminant analysis. Twelve patients with RA, 11 with SLE, and 8 with MC had evidence of sicca syndrome and were then classified as having a secondary (2 degree) SS. When comparing the various disease groups to each other, it was always possible to select different combinations of clinical and serological variables which defined highly significant discriminant functions. In addition, some parameters appeared to have a stronger discriminant power between different disease groups. For instance, 1 degree SS was well discriminated from RA by anti-Ro antibodies (Ab) and normal C-reactive protein (CRP) levels, from SLE by normal complement levels and the positivity of rheumatoid factor, from MC by the absence of liver involvement and normal complement levels. While anti-La Ab had the highest value in differentiating patients with 1 degree from those with 2 degrees SS, anti-Ro Ab and recurrent parotid swelling seem to be typical features of patients with SS with respect to those with other connective tissue disease but without sicca syndrome.
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80
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Wu DH, Shiffman CA, Sridhar S. Field variation of the penetration depth in ceramic Y1Ba2Cu3Oy. PHYSICAL REVIEW. B, CONDENSED MATTER 1988; 38:9311-9314. [PMID: 9945742 DOI: 10.1103/physrevb.38.9311] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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81
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Naghibi M, Smith RP, Baltch AL, Gates SA, Wu DH, Hammer MC, Michelsen PB. The effect of diabetes mellitus on chemotactic and bactericidal activity of human polymorphonuclear leukocytes. Diabetes Res Clin Pract 1987; 4:27-35. [PMID: 3121272 DOI: 10.1016/s0168-8227(87)80030-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We studied the bactericidal activity (against P. aeruginosa) and chemotactic ability of polymorphonuclear leukocytes from 26 diabetic patients in three treatment groups (oral hypoglycemic, daily insulin, and continuous insulin infusion). Patients were studied before entry into intensified management protocols, and after intensified management in 11 of the 26 patients. Diabetic serum had a persistent inhibitory effect on both diabetic and normal white cells, but normal serum was unable to fully correct diabetic white cell killing to control values. After intensified management of diabetes, there was an improvement in bactericidal function of diabetic patient white cells, but not in the effect of diabetic serum. Diabetic serum, and to a lesser extent diabetic white blood cells, are defective mediators of killing of P. aeruginosa. Chemotaxis was normal in all patient groups. These findings confirm the earlier work of others showing that some patients with diabetes mellitus have a defect in host defense against infection with bacteria.
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82
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Wu DH, Baltch AL, Smith RP, Conley PE. Effect of aztreonam in combination with azlocillin or piperacillin on Pseudomonas aeruginosa. Antimicrob Agents Chemother 1984; 26:519-21. [PMID: 6440474 PMCID: PMC179956 DOI: 10.1128/aac.26.4.519] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Aztreonam, a synthetic monobactam antimicrobial agent specifically active against aerobic, gram-negative microorganisms, was studied in combination with the extended-spectrum penicillins azlocillin and piperacillin against 46 strains of Pseudomonas aeruginosa. Of these strains, 4.3% were synergistically inhibited, and 19.7% showed evidence for an additive effect of the antibiotics. All other strains showed indifference. The addition of cefoxitin to these combinations increased the MICs of azlocillin and piperacillin by two to three tubes, whereas zero- to one-tube increases were noted for aztreonam MICs. Attempts to block cefoxitin-induced beta-lactamase production by using clindamycin were unsuccessful even at high clindamycin concentrations.
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83
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Wu DH, Baltch AL, Smith RP. In vitro comparison of Pseudomonas aeruginosa isolates with various susceptibilities to aminoglycosides and ten beta-lactam antibiotics. Antimicrob Agents Chemother 1984; 25:488-90. [PMID: 6428308 PMCID: PMC185558 DOI: 10.1128/aac.25.4.488] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Susceptibilities of 98 clinical isolates of Pseudomonas aeruginosa, including 33 strains with known mechanisms of amikacin resistance, were tested by the agar dilution method against 10 beta-lactam drugs. Ceftazidime, imipenem, and cefsulodin had the greatest activity, regardless of the aminoglycoside susceptibilities. The strains which were highly resistant to amikacin appeared to be less susceptible to some beta-lactam drugs, especially if their resistance was related to amikacin-inactivating enzymes; statistical significance, however, was observed for aztreonam only.
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84
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Wu DH. [Detection of anti-SSA and anti-SSB antibodies and its clinical significance]. ZHONGHUA YI XUE ZA ZHI 1984; 64:194-6. [PMID: 6432277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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86
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Abstract
Viable and functional luteal cells were prepared, using a combination of hyaluronidase, collagenase, and a low concentration of trypsin in a Dulbecco's modified Eagle medium containing 0.5% bovine serum albumin and 3.3 mM Ca++, from corpora lutea taken from 2-day pregnant rats. The viability and functional capacity of the dispersed cells were evaluated by electronmicroscopy and by measuring steroidogenic capicity during perifusion. Dispersed luteal cells previously exposed in vivo to biphasic prolactin (PRL) surges were found to respond during perifusion to as little as 0.5 ng/ml LH by increased steroid secretion. The net progesterone synthesis and secretion remained elevated over a time course of 2 1/2 hours perifusion, and the magnitude of the luteotropic stimulation was dose dependent on LH. However, luteotropic stimulation of LH could not be maintained beyond 2 1/2 h without renewed (in vitro) PRL exposure. PRL by itself maintained the low initial secretion rate of progesterone but demonstrated no stimulatory effect. Different steroidogenic responses were noted during the in vitro administration of LH alone and the administration of LH plus PRL. In the former case, the decreasing rate of progesterone secretion was accompanied by an increasing 20 alpha-dihydroprogesterone secretion, suggesting that luteal 20 alpha-hydroxysteroid dehydrogenase activity was not suppressed. In the latter case, progesterone secretion was maintained and 20 alpha-dihydroprogesterone secretion fell suggesting an inhibitory action by PRL against 20 alpha-hydroxysteroid dehydrogenase activity. Dispersed luteal cells, preincubated at 36 C in medium containing only PRL, retained viability and functional capacity in response to LH-PRL stimulation for periods of time up to 48 h. Preincubation with LH alone did not prolong cell viability.
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