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Mansencal N, Joseph T, Vieillard-Baron A, El Hajjam M, Bendaoud M, Drouin A, Jondeau G, Lacombe P, Jardin F, Dubourg O. [Negative D-dimers and peripheral pulmonary embolism]. ARCHIVES DES MALADIES DU COEUR ET DES VAISSEAUX 2003; 96:1143-8. [PMID: 15248438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
The measurement of D-dimers is a recent addition to the diagnostic strategy of pulmonary embolism and has been shown to be a valuable tool with excellent sensitivity. However, there have been rare reports of patients with pulmonary embolism but negative D-dimer tests. The object of this study was to study patients with pulmonary embolism but negative D-dimers and to compare them with a population of patients with pulmonary embolism and raised D-dimers. One hundred and fifty consecutive patients admitted for pulmonary embolism were included in this study. All underwent measurement of D-dimers (normal <500 ng/ml) by an ELISA technique. The data of clinical examination and complementary investigations were analysed with respect to the D-dimers result. The sensitivity of raised D-dimers for pulmonary embolism was 96% (6 patients had results <500 ng/ml). The finding of chest pain was statistically greater in the group with negative D-dimers (p=0.01). In these cases, the emboli were all distal (p=0.0003), the average Miller index was significantly lower than in patients with high D-dimers (p=0.04) and the diagnostic value of ultrasound investigations (echocardiography, ultrasonography of lower limb veins) was less (p<0.0001). The authors conclude that measurement of D-dimers by the ELISA method may be non-diagnostic in distal pulmonary embolism and one explanation could be the less extensive thromboembolic process. In cases with negative D-dimers, a strong clinical suspicion of pulmonary embolism should lead to the request for further investigations.
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Mansencal N, Chikli F, Joseph T, Digne F, Jondeau G, Lacroix H, Dubourg O. [Isolated and asymptomatic Brugada syndrome. A case report]. Ann Cardiol Angeiol (Paris) 2002; 51:199-202. [PMID: 12471798 DOI: 10.1016/s0003-3928(02)00103-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The case report of a 32-year-old man with a Brugada syndrome is presented. He was asymptomatic and without familial history of sudden death or syncope. Diagnosis criteria for Brugada syndrome were 1--a pattern of right bundle branch block and ST-segment elevation in leads V1 and V2 on the ECG, 2--no cardiac structural anomalies. Symptomatic patients with this electrical anomaly are at high risk of sudden death and need an automatic implantable defibrillator. The outcome and the treatment of asymptomatic patients are a matter of debate and are discussed in this report.
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Joseph T, Wooden R, Bryant A, Zhong M, Lu Z, Foster DA. Transformation of cells overexpressing a tyrosine kinase by phospholipase D1 and D2. Biochem Biophys Res Commun 2001; 289:1019-24. [PMID: 11741292 DOI: 10.1006/bbrc.2001.6118] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phospholipase D (PLD) activity is elevated in response to most mitogenic signals. Two mammalian PLD genes (PLD1 and PLD2) have been cloned and their gene products have been characterized. PLD1 is a downstream target of the Ras/RalA GTPase cascade implicated in mitogenic and oncogenic signaling. Consistent with a role in mitogenic signaling, elevated expression of PLD1 transforms cells overexpressing the epidermal growth factor (EGF) receptor (EGFR). However, PLD2 colocalizes with the EGFR in caveolin-enriched light membrane microdomains. We therefore investigated whether PLD2 could also contribute to the transformation of cells overexpressing a tyrosine kinase. We report here that elevated expression of PLD2 transforms rat fibroblasts overexpressing either the EGFR or c-Src. Since overexpression of a tyrosine kinase is a common genetic alteration in several human cancers, these data suggest that elevation of either PLD1 or PLD2 may contribute to the progression to a malignant phenotype in cells with elevated tyrosine kinase activity.
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Subramanyam K, David J, Joseph T. Interaction of flunarizine with sodium valproate or ethosuximide in gamahydroxybutyrate induced absence seizures in rats. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 2001; 39:998-1001. [PMID: 11883524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
Sodium valproate(VPA), ethosuximide(ESM), 200 mg/kg ip and flunarizine (FLU) 5 or 10 mg/kg ip were first administered independently to rats in order to study their effects on behavioural and EEG aspects of spike and wave discharges (SWDs) induced by y- hydroxybutyrate (GHB,100 mg/kg ip). GHB treated rats show behavioural changes and concomitant repetitive EEG episodes of 7 to 9 Hz SWDs, mimicking human absence seizures (AS), and can be used as a pharmacological model. The number and duration of SWDs were calculated for 1 hr from the EEG and were parameters for drug evaluation. VPA and ESM at 200 mg/kg, significantly reduced SWD number and duration/hr, while FLU showed significant reduction only at 10 but not at 5 mg/kg. Combination of FLU, 10 mg/kg with either VPA or ESM showed significant reduction of SWD number and duration, suggesting an additive effect of the anti-absence agents with the calcium channel blocker, FLU, on experimental absence seizures in rats.
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Penna P, Cox E, Joseph T, Lehman L, Morrow T, Richter A, Sowers J, Tepper D. Roundtable discussion: Part I--Epidemiologic, demographic, and treatment challenges in hypertension. MANAGED CARE INTERFACE 2001; Suppl C:10-6. [PMID: 11183934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Hypertension is one of the most pervasive medical disorders in this country. As the nation's population ages, the number of patients with hypertension can be expected to rise substantially. On December 9, 1999, a panel of managed care medical directors, pharmacy directors, clinicians, and health economists convened in Irvine, Texas to discuss aspects of hypertension management and economic analysis. This roundtable is presented in three parts, including (1) a summary of the challenges of hypertension management from the point of view of the clinician, (2) the introduction of a pharmacoeconomic model of hypertension management, and (3) a discussion of how health plans approach this insidious disorder.
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Penna P, Cox E, Joseph T, Lehman L, Morrow T, Richter A, Sowers J, Tepper D. Roundtable discussion: Part II--Development of a pharmacoeconomic model in hypertension. MANAGED CARE INTERFACE 2001; Suppl C:17-23. [PMID: 11183935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Antihypertensive medications are targeted by most health plans as a major cost center. However, the efficacy of these medications, their side effects, and their resulting ability to prevent serious long-term complications must be factored into the value equation. To illustrate the possible economic effects of a single antihypertensive agent's inclusion on a health plan's drug formulary, an innovative pharmacoeconomic model was developed. In this portion of the roundtable, the design, results, and caveats of this model are discussed.
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Qanadli SD, El Hajjam M, Vieillard-Baron A, Joseph T, Mesurolle B, Oliva VL, Barré O, Bruckert F, Dubourg O, Lacombe P. New CT index to quantify arterial obstruction in pulmonary embolism: comparison with angiographic index and echocardiography. AJR Am J Roentgenol 2001; 176:1415-20. [PMID: 11373204 DOI: 10.2214/ajr.176.6.1761415] [Citation(s) in RCA: 444] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVE This study was designed to define and evaluate a specific index to quantify arterial obstruction with helical CT in acute pulmonary embolism. MATERIALS AND METHODS Fifty-four patients (mean age, 56 years) with proven pulmonary emboli among 158 consecutive patients, who had undergone both CT and pulmonary angiography for clinically suspected pulmonary embolism, were eligible for the study. The CT obstruction index was defined as (n. d) (n, value of the proximal clot site, equal to the number of segmental branches arising distally; d, degree of obstruction scored as partial obstruction [value of 1] or total obstruction [value of 2]). We compared the CT obstruction index with pulmonary arterial obstruction on angiography (assessed by the Miller index), using linear regression, and correlated it with findings on echocardiography. Interobserver variability was determined for both CT and pulmonary angiography indexes. RESULTS The CT obstruction index (29% +/- 17%) and the Miller index (43% +/- 25%) were well correlated (r = 0.867, p < 0.0001) with an excellent concordance between investigators for both the CT index (r = 0.944, p < 0.0001) and the Miller index (r = 0.904, p < 0.0001). A CT obstruction index greater than 40% identified more than 90% of patients with right ventricular dilatation. CONCLUSION The degree of arterial obstruction in pulmonary embolism may be quantified by a specific CT index that appears reproducible and highly correlated to the previously described index with pulmonary angiography. Further evaluations are needed to investigate the usefulness of the CT obstruction index for stratification of patient risk and determining therapeutic options.
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Joseph R, Joseph T, Joseph J. Volatile essential oil constituents of Alpinia smithiae (Zingiberaceae). REV BIOL TROP 2001; 49:509-12. [PMID: 11935900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
The composition of leaf and rhizome essential oils of Alpinia smithiae that grow wild in the Western Ghats of Kerala (South India) was analysed by gas chromatography. The major components were beta-caryophyllene, sabinene, myrcene and 1,8-cineole in both samples, but variation in the yield of oil as well as the major components between the two plant parts was observed.
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Qanadli SD, Mesurolle B, Aegerter P, Joseph T, Oliva VL, Guertin MC, Dubourg O, Fauchet M, Goeau-Brissonniére OA, Lacombe P. Volumetric quantification of coronary artery calcifications using dual-slice spiral CT scanner: improved reproducibility of measurements with 180 degrees linear interpolation algorithm. J Comput Assist Tomogr 2001; 25:278-86. [PMID: 11242229 DOI: 10.1097/00004728-200103000-00023] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
PURPOSE The purpose of this work was to determine the reproducibility of coronary total calcium score (TCS) with dual-slice helical CT and compare three acquisition protocols. METHOD Fifty patients (59 +/- 10 years old) underwent dual-slice helical CT (collimation = 2 x 2.5 mm) and coronary angiography. Two successive scans were performed, resulting in three sets of images: pitch = 1, 360 degrees linear interpolation (LI) (A360); pitch = 1, 180 degrees LI (A180); and pitch = 1.5, 180 degrees LI (B180). TCS values, calculated using a volumetric method with a threshold of 90 HU, were compared, and the interscan variation was determined. Diagnostic performances were compared with receiver operating characteristic curves. RESULTS Protocol A360 provided significantly lower TCS than protocols A180 and B180 (p < 0.0001). No statistical difference was seen between A180 and B180, which provided the lowest interscan variation (40 +/- 58%). However, no significant clinical impact of the observed interscan variations was found. CONCLUSION Reproducibility of TCS with dual-slice helical CT is improved by the 180 LI algorithm. However, dual-slice helical CT is not sufficiently reproducible to allow serial quantification of TCS over time.
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Joseph T, Vieillard-Baron A, Chikli F, Goeau-Brissonière O, Coggia M, Lacombe P, Dubourg O. Left ventricular volume analysis for the detection of coronary artery disease during dobutamine stress echocardiography in patients undergoing vascular surgery. EUROPEAN JOURNAL OF ECHOCARDIOGRAPHY : THE JOURNAL OF THE WORKING GROUP ON ECHOCARDIOGRAPHY OF THE EUROPEAN SOCIETY OF CARDIOLOGY 2000; 1:263-70. [PMID: 11916604 DOI: 10.1053/euje.2000.0039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
AIMS The purpose of the study was to prospectively evaluate the effectiveness of left ventricular volume changes analysis as compared to wall motion assessment for detecting coronary artery disease during dobutamine stress echocardiography in patients undergoing elective vascular surgery. METHODS AND RESULTS Left ventricular volumes, measured by using the ellipsoid biplane method combining the apical four- and two-chamber echocardiographic views, and classical wall motion score were determined at rest and peak stress (dobutamine infusion 5-40 microg/kg/min+/- atropine 0.25-1mg) in 68 consecutive patients. A positive test was defined as a decrease of less than 15% in left ventricular end-diastolic or end-systolic volume at peak stress for volume analysis and as an increase in score between rest and peak stress in one or more segments for wall motion assessment. Stress test was not analysable in five patients. Coronary angiography revealed significant coronary artery disease (coronary stenosis >or=70%) in 28/63 (44%) patients: one-vessel in 15, two- or three-vessel disease in 13. Overall sensitivity and specificity for coronary artery disease detection were 56% and 97% with left ventricular volume analysis, as compared to 64% and 89% with wall motion assessment. For patients with two- or three-vessel disease, sensitivity and specificity of volume analysis reached 92%. CONCLUSION The present data suggest that left ventricular volume change analysis during dobutamine stress echocardiography could be a reliable method for the detection of extensive coronary artery disease for patients undergoing vascular surgery.
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Qanadli SD, Hajjam ME, Mesurolle B, Barré O, Bruckert F, Joseph T, Mignon F, Vieillard-Baron A, Dubourg O, Lacombe P. Pulmonary embolism detection: prospective evaluation of dual-section helical CT versus selective pulmonary arteriography in 157 patients. Radiology 2000; 217:447-55. [PMID: 11058644 DOI: 10.1148/radiology.217.2.r00nv01447] [Citation(s) in RCA: 193] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
PURPOSE To evaluate the accuracy of dual-section helical computed tomography (CT) in acute pulmonary embolism (PE) diagnosis. MATERIALS AND METHODS Of 204 consecutive patients with clinically suspected acute PE (mean age, 58 years +/- 14 [SD]), 158 were enrolled. All patients underwent dual-section helical CT (2.7-mm effective section thickness) and selective pulmonary arteriography within 12 hours of each other. Each image was analyzed independently by two observers, who determined image quality and presence of PE among arterial segments, including at the subsegmental level. The final diagnosis was made with consensus. RESULTS Selective pulmonary arteriography was considered optimal in 147 (93%), suboptimal in 10 (6%), and inconclusive in one (0.6%) of 158 patients. Dual-section helical CT findings were considered technically optimal in 140 (89%), suboptimal in 11 (7%), and inconclusive in six (4%). Selective pulmonary arteriography demonstrated PE in 62 patients. Four (6%) of 62 patients had isolated subsegmental PE. The sensitivity of dual-section helical CT was 90%, and the specificity was 94%. The positive and negative predictive values were 90% and 94%, respectively. CONCLUSION Dual-section helical CT is an improvement in helical CT that offers a high sensitivity and specificity for the depiction of PE, including at the subsegmental level. Dual-section helical CT can replace pulmonary arteriography for the direct demonstration of PE in a majority of patients.
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Houbouyan-Reveillard LL, Mihoubi A, Houdijk WP, Qanadli S, Joseph T, Courret JP, Page B, Goguel AF. Preliminary evaluation of two new rapid immunoturbidimetric D-dimer assays in patients with clinically suspected venous thromboembolism (VTE). Thromb Haemost 2000; 84:770-4. [PMID: 11127853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The practical utility and diagnostic accuracy of two new rapid, automated and quantitative immunoturbidimetric D-dimer methods have been evaluated in a population of 123 randomly selected patients with suspected VTE. The STA Liatest D-dimer and MDA D-dimer methods are based on the photo-optical measurement of the rate of agglutination of antibody-coated latex particles. The VIDAS D-dimer automated Elisa was used as the reference method. Diagnosis was confirmed in 51 patients (29 PE, 19 DVT, 3 DVT+PE). The immunoturbidimetric methods compared favorably with the VIDAS Elisa as judged from the correlation coefficients of linear regression lines (r = 0.82, MDA vs VIDAS; r = 0.75, STA vs VIDAS) and areas under the curve of ROC plots (VIDAS 0.83; STA 0.83; MDA 0.81). At a discriminant value of 500 ng/mL, all three D-dimer assays showed high sensitivity (96-98%), high NPV (93-97%) and moderate specificity (39-42%). Reproducibility of results around the cut-off is an important aspect of the diagnostic utility of D-dimer assays. CV's of duplicate determinations in this critical zone showed average values of 5.4% and 17.0% for MDA and STA, respectively. These data demonstrate that such rapid and automated latex-based methods for the quantitative measurement of D-dimer hold promise as reliable and cost-efficient approaches for the exclusion of VTE. Prospective patient management studies will be required to confirm this.
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Joseph T, Coirault C, Lecarpentier Y. Species-dependent changes in mechano-energetics of isolated cardiac muscle during hypoxia. Basic Res Cardiol 2000; 95:378-84. [PMID: 11099164 DOI: 10.1007/s003950070036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The present study investigates the mechanical and energetic changes induced by hypoxia in isolated cardiac muscles of different species characterized by different myosin isoforms. Classic mechanical parameters of contraction and energetic parameters derived from the tension-velocity relationship were studied in rat and guinea pig left ventricular papillary muscles and in frog ventricular strips before and after 15 min hypoxia (n = 8 in each group). The isomyosin pattern is predominantly V1 with high ATPase activity in rat and V3 with low ATPase activity in guinea pig and frog heart ventricles. At baseline, cardiac mechanical performance was greater in rat than in guinea pig and frog muscle, but the economy of tension generation did not differ significantly between the three species. Hypoxia significantly decreased myocardial mechanical performance in all three groups. Mechanical impairment was more marked in rat than in the other two species and was intermediate in guinea pig. The energetic consequences of hypoxia differed according to species and in a different manner from the mechanical parameters. Hypoxia decreased the economy of tension generation in rat heart, in contrast to no change in guinea pig and frog muscle. These results suggest that in terms of mechano-energetic properties, cardiac muscles with V1 isomyosin were more sensitive to hypoxia than those containing V3 isomyosin.
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Kumaresan S, David J, Joseph T. Comparative profiles of sodium valproate and ethosuximide on electro-behavioural correlates in gamma-hydroxybutyrate and pentylenetetrazol induced absence seizures in rats. INDIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY 2000; 44:411-8. [PMID: 11214495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Sodium valproate (VPA) and ethosuximide (ESM) were compared on behavioural and EEG changes in gamma-hydroxybutyrate (GHB) and pentylenetetrazole (PTZ) rat models of Absence Seizures (AS). Both GHB, 100 mg/kg i.p. and PTZ, 20 mg/kg i.p., produced repetitive episodes of staring and immobility with concomitant 6 to 9 Hz spike and wave discharges (SWDs) in the EEG. The parameters used for drug evaluation were the number and duration of SWDs/hour. Though the number of SWDs/hour produced by GHB and PTZ were not significantly different, the duration of SWDs was significantly longer in GHB treated rats (P < 0.001) VPA and ESM, at 200 mg/kg i.p., reduced SWD number and duration in GHB pretreated rats, whereas ESM, 50 mg/kg i.p., was four times more effective than VPA, 200 mg/kg i.p., in the PTZ model. Phenytoin (PHY) 20 and Carbamazepine (CBZ) 10 mg/kg i.p., worsened AS, a feature which has also been reported clinically. Both rat models of experimental AS can be used to defect potential anti-absence activity in new chemical entities.
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Choussat R, Black AJ, Bossi I, Joseph T, Fajadet J, Marco J. Long-term clinical outcome after endoluminal reconstruction of diffusely degenerated saphenous vein grafts with less-shortening wallstents. J Am Coll Cardiol 2000; 36:387-94. [PMID: 10933347 DOI: 10.1016/s0735-1097(00)00724-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES This study was designed to evaluate the immediate and long-term clinical results of patients undergoing endoluminal reconstruction in diffusely degenerated saphenous vein grafts (SVGs) with elective implantation of one or more less-shortening Wallstents. BACKGROUND The optimal treatment strategy for patients with diffusely degenerated SVGs is controversial. Endoluminal reconstruction by stent implantation is one proposed strategy; however, there are few data regarding long-term clinical outcome. METHODS Between May 1995 and September 1998, 6,534 consecutive patients underwent angioplasty in our institution, including 440 who were treated for SVG lesions. Of these, 126 (115 men, 11 women, median age 69.5 years, range: 33-86 years) with old SVGs (mean age: 13+/-5 years) diffusely degenerated stenosed or occluded (mean lesion length: 27+/-12 mm) were treated electively with implantation of one or multiple (total 197) less-shortening Wallstents. RESULTS Before discharge, 13 patients (10.3%) sustained at least one major cardiovascular event, including 4 deaths (3.2%), 11 myocardial infarctions (MI) (8.7%), and 3 repeat revascularizations (target vessel = 1, nontarget vessel = 2, 2.4%). Surviving patients were followed for 22+/-11 months: 13 patients (11.1%) died, 11 (9.4%) sustained an MI, 37 underwent angioplasty (31.6%), and 4 (3.4%) underwent bypass surgery. The estimated three-year event-free survival rates (freedom from death, and freedom from death/MI/target vessel revascularization) were (mean +/- SE) 81.1+/-7.8% and 43.2+/-18.5%, respectively. CONCLUSIONS The long-term clinical outcome of patients undergoing endoluminal reconstruction in diffusely degenerated SVG is relatively poor, mainly because of a high incidence of death or MI and the frequent need for repeat angioplasty. It is unlikely that percutaneous intervention alone will provide a satisfactory or definitive solution for these patients.
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Xu L, Shen Y, Joseph T, Bryant A, Luo JQ, Frankel P, Rotunda T, Foster DA. Mitogenic phospholipase D activity is restricted to caveolin-enriched membrane microdomains. Biochem Biophys Res Commun 2000; 273:77-83. [PMID: 10873567 DOI: 10.1006/bbrc.2000.2907] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phospholipase D (PLD) activity is elevated in response to the oncogenic stimulus of several signaling oncogenes. PLD activity is also elevated in response to peptide growth factors, indicating that PLD likely plays an important role in mitogenic signaling. Many proteins that mediate mitogenic signaling are localized in caveolin-enriched membrane microdomains (CEMMs). We report here that the elevated PLD activity in NIH 3T3 cells transformed by activated oncogenic forms of Src, Ras, and Raf is largely restricted to the CEMMs. Likewise, the PLD activity stimulated by epidermal growth factor is also restricted to the CEMMs. Although both PLD1 and PLD2 were found in CEMMs, neither was particularly enriched in the CEMMs of the transformed relative to the parental cells, indicating that it is the specific activity of PLD that is increased in the CEMMs. An apparent PLD substrate specificity in transformed cells for phosphatidylcholine lacking arachidonate acyl groups is also explained by the localization of activity in the CEMMs where [(3)H]arachidonate-labeled PC was excluded. These data indicate that mitogenic signals through PLD are initiated in CEMMs where many signaling molecules colocalize.
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Joseph T, Yeoh HH, Loh CS. Somatic embryogenesis, plant regeneration and cyanogenesis in Manihot glaziovii Muell. Arg. (ceara rubber). PLANT CELL REPORTS 2000; 19:535-538. [PMID: 30754896 DOI: 10.1007/s002990050769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The report describes a system for somatic embryogenesis and direct plant regeneration from the embryos of Manihot glaziovii. Somatic embryos were obtained by culturing young leaf lobes (3-6 mm long) adjacent to the apex in Murashige and Skoog medium containing 18 μM 2,4-dichlorophenoxy acetic acid for 20 days and then transferring them to a maturation medium with 0.5 μM 6-benzylaminopurine. Secondary embryogenesis was induced from cotyledonary segments of somatic embryos by using the same protocol as that for primary embryogenesis. For regeneration, somatic embryos were cultured in medium supplemented with 10-4 M kinetin and 53.4% of them developed into plantlets. Linamarin and linamarase were not detected in calli or in somatic embryos. Linamarin content was found to be highest in leaves of regenerated plantlets, followed by stem and root tissues. Levels of linamarase activity were almost the same in leaves and stem tissues and very low in roots.
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Penna P, Cox E, Joseph T, Lehman L, Morrow T, Richter A, Sowers J, Tepper D. Roundtable discussion: Part III--Hypertension management in health plans. MANAGED CARE INTERFACE 2000; Suppl C:24-31. [PMID: 11183936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
In the final section of the roundtable discussion, participants describe how their individual managed care plans approach hypertension from the standpoints of disease management targeting, strategies to combat noncompliance, and how these plans utilize pharmacoeconomic information in drug formulary decision making.
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Lu Z, Hornia A, Joseph T, Sukezane T, Frankel P, Zhong M, Bychenok S, Xu L, Feig LA, Foster DA. Phospholipase D and RalA cooperate with the epidermal growth factor receptor to transform 3Y1 rat fibroblasts. Mol Cell Biol 2000; 20:462-7. [PMID: 10611224 PMCID: PMC85102 DOI: 10.1128/mcb.20.2.462-467.2000] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
3Y1 rat fibroblasts overexpressing the epidermal growth factor (EGF) receptor (EGFR cells) become transformed when treated with EGF. A common response to oncogenic and mitogenic stimuli is elevated phospholipase D (PLD) activity. RalA, a small GTPase that functions as a downstream effector molecule of Ras, exists in a complex with PLD1. In the EGFR cells, EGF induced a Ras-dependent activation of RalA. The activation of PLD by EGF in these cells was dependent upon both Ras and RalA. In contrast, EGF-induced activation of Erk1, Erk2, and Jun kinase was dependent on Ras but independent of RalA, indicating divergent pathways activated by EGF and mediated by Ras. The transformed phenotype induced by EGF in the EGFR cells was dependent upon both Ras and RalA. Importantly, overexpression of wild-type RalA or an activated RalA mutant increased PLD activity in the absence of EGF and transformed the EGFR cells. Although overexpression of PLD1 is generally toxic to cells, the EGFR cells not only tolerated PLD1 overexpression but also became transformed in the absence of EGF. These data demonstrate that either RalA or PLD1 can cooperate with EGF receptor to transform cells.
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Hornia A, Lu Z, Sukezane T, Zhong M, Joseph T, Frankel P, Foster DA. Antagonistic effects of protein kinase C alpha and delta on both transformation and phospholipase D activity mediated by the epidermal growth factor receptor. Mol Cell Biol 1999; 19:7672-80. [PMID: 10523655 PMCID: PMC84804 DOI: 10.1128/mcb.19.11.7672] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Downregulation of protein kinase C delta (PKC delta) by treatment with the tumor-promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) transforms cells that overexpress the non-receptor class tyrosine kinase c-Src (Z. Lu et al., Mol. Cell. Biol. 17:3418-3428, 1997). We extended these studies to cells overexpressing a receptor class tyrosine kinase, the epidermal growth factor (EGF) receptor (EGFR cells); like c-Src, the EGF receptor is overexpressed in several human tumors. In contrast with expectations, downregulation of PKC isoforms with TPA did not transform the EGFR cells; however, treatment with EGF did transform these cells. Since TPA downregulates all phorbol ester-responsive PKC isoforms, we examined the effects of PKC delta- and PKC alpha-specific inhibitors and the expression of dominant negative mutants for both PKC delta and alpha. Consistent with a tumor-suppressing function for PKC delta, the PKC delta-specific inhibitor rottlerin and a dominant negative PKC delta mutant transformed the EGFR cells in the absence of EGF. In contrast, the PKC alpha-specific inhibitor Go6976 and expression of a dominant negative PKC alpha mutant blocked the transformed phenotype induced by both EGF and PKC delta inhibition. Interestingly, both rottlerin and EGF induced substantial increases in phospholipase D (PLD) activity, which is commonly elevated in response to mitogenic stimuli. The elevation of PLD activity in response to inhibiting PKC delta, like transformation, was dependent upon PKC alpha and restricted to the EGFR cells. These data demonstrate that PKC isoforms alpha and delta have antagonistic effects on both transformation and PLD activity and further support a tumor suppressor role for PKC delta that may be mediated by suppression of tyrosine kinase-dependent increases in PLD activity.
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Joseph T, Fajadet J, Jordan C, Cassagneau B, Laborde JC, Laurent JP, Marco J. Coronary stenting in diabetics: Immediate and mid-term clinical outcome. Catheter Cardiovasc Interv 1999; 47:279-84. [PMID: 10402276 DOI: 10.1002/(sici)1522-726x(199907)47:3<279::aid-ccd3>3.0.co;2-p] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Balloon angioplasty in diabetics is associated with acceptable immediate results but with high rates of restenosis, target vessel revascularization, and late mortality. The impact of coronary stenting on the outcome of these patients remains controversial. We reported the immediate and mid-term clinical outcome of 272 consecutive diabetic patients, representing 12.5% of the population undergoing coronary stenting between May 1995 and April 1997. Diabetes mellitus was insulin-requiring in 58 patients and non-insulin-requiring in 214. Stenting performed on large vessels (mean diameter >/=3 mm) was successful in 99.2% of nondiabetic patients and in all cases in diabetics. During in-hospital stay, the complications rate, including mortality, nonfatal myocardial infarction, emergency coronary bypass surgery, and stent subacute thrombosis, was similar in nondiabetic patients, insulin-requiring, and non-insulin-requiring diabetics (2.55%, 0%, and 2.0%, respectively). No complication occurred in the insulin-requiring group. One patient (0.5%) died from myocardial infarction and another (0.5%) presented a nonfatal myocardial infarction (subacute stent thrombosis) in the non-insulin-requiring group. The clinical follow-up (mean length 13 +/- 8 months) was obtained in 93% and 97% of the insulin-requiring and non-insulin-requiring diabetics, respectively. Overall mortality was significantly higher in insulin-requiring patients (9.3% vs. 2.4%). Nonfatal myocardial infarction and target lesion revascularization rates were similar in the two groups (0% vs. 0.5% and 8.2% vs. 10.5%). These results suggest that coronary stenting in diabetics could be performed with acceptable immediate and mid-term results. Cathet. Cardiovasc. Intervent. 47:279-284, 1999.
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Abstract
The computed tomographic (CT) scanning characteristics of a case of intra-fourth-ventricle mature teratoma in a 15-month-old child are described and correlated with intraoperative findings.
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100
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Joseph T, Fajadet J, Marco J. [Reconstruction of saphenous vein grafts using Wallstent endoprostheses. Immediate and mid-term results]. ARCHIVES DES MALADIES DU COEUR ET DES VAISSEAUX 1999; 92:405-10. [PMID: 10326148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Balloon angioplasty of degenerated saphenous vein grafts is associated with a high incidence of restenosis and of cardiac events in the medium and long term. Implantation of stents has reduced the incidence of these complications in patients with focal lesions. The authors report the short and medium term clinical results of saphenous vein grafts reconstruction in cases of diffuse graft disease with Wallstent endoprostheses in a series of 73 patients. All were pretreated with aspirin, ticlopidine and enoxaparine started 72 hours before the procedure and 15 also received c7E3Fab during angioplasty. One hundred and twenty stents were implanted in 90 saphenous vein grafts. There were 5 deaths (6.9%), 2 of which were cardiac, during the hospital period. One patient (1.4%) underwent secondary coronary bypass surgery. Eight patients (11%) suffered distal embolisation resulting in non-Q wave infarction. Clinical follow-up for an average of 13 months (3-26 months) was obtained in 91% of patients. Five (8.1%) died, three of cardiac causes, and one patient (1.7%) suffered a non-lethal myocardial infarction. A repeat revascularisation procedure of the culprit lesion was performed in 9 patients (15.8%). Angioplasty of other lesions was carried out in 7 patients (12.3%). Reconstruction of venous bypass grafts with diffuse lesions by implantation of Wallstent endoprostheses associated with preventive antiaggregant and anticoagulant therapy is associated with a risk of immediate complications. The medium-term results indicate high morbidity and cardiac mortality rates.
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