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Ennifar E, Nikulin A, Serganov A, Garber M, Ehresmann C, Nikonov S, Dumas P. The crystal structure of two UUCG tetraloops. Acta Crystallogr A 2000. [DOI: 10.1107/s0108767300025861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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77
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Briki F, Busson B, Kreplak L, Dumas P, Doucet J. Exploring a biological tissue from atomic to macroscopic scale using synchrotron radiation: example of hair. Cell Mol Biol (Noisy-le-grand) 2000; 46:1005-16. [PMID: 10976880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
A combined approach, using synchrotron radiation-based diffraction and infrared microspectrometry, has been used to study the structure and molecular composition of hair samples. These methods allowed us to get an insight at different structural scales into the composition and structure of hair. Firstly, information about the configuration of amino-acid residues was obtained at atomic scale, secondly, a model was presented for the geometry and the packing of the microfibrils at medium scale and finally different structural zones were evidenced by microdiffraction at macroscopic scale. We also showed that the two main components of hair--proteins and lipids--are not evenly distributed within the fiber. In addition, these two components exhibit different structure, depending upon their location. Moreover, diffraction and microdiffraction data indicate that the cuticle zone is mainly composed of lipid granules, whereas the cortex and the medulla zones are composed primarily of alpha-keratin. Infrared microspectroscopy, using an enhanced lateral resolution thanks to synchrotron radiation, indicates, on one hand, that the protein structure between the cuticle and cortex are different, and on the other hand, that the concentration of lipids, inside the medulla, is much higher than everywhere else. This work emphasizes the complementarity between both techniques, and highlights the potentialities they can offer in the case of various other studies in biology.
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Dumas P, Bouafia S, Gutknecht C, Saoud M, Daléry J, d'Amato T. [Validation of French versions of magical ideation and perceptual aberrations questionnaires]. L'ENCEPHALE 2000; 26:42-6. [PMID: 11064838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Chapman and colleagues have developed symptom-oriented scales based on Meehl's manual of schizotypy, such as the Social Anhedonia (SA) and Physical Anhedonia (PhA) Scales, the Magical Ideation Scale (MIS), and the Perceptual Aberration Scale (PAS). Whereas Chapman's scales of psychosis proneness are the most internationally used instruments for the assessment of schizotypy, some of them, such as MIS and PAS, were still not available in French. We reported here the validation study of the MIS and the PAS French versions that we had published previously. This study was conducted in a sample of 233 students (males: n = 108; females: n = 125; mean age: 21.17 +/- 1.47; mean educational level: 13.36 +/- 1.06). The French versions of the MIS and the PAS have high internal reliability (MIS: Cronbach's alpha = 0.85; PAS: Cronbach's alpha = 0.88). French norms are given for each of these scales. They are respectively 19/30 for the MIS and 17/35 for the PAS high cutoff scores without any difference when gender was considered. These results are very closed to those found by Chapman and colleagues for University of Wisconsin undergraduate students.
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79
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Lefèvre T, Louvard Y, Loubeyre C, Dumas P, Piéchaud JF, Krol M, Benslimane A, Premchand RK, Morice MC. A randomized study comparing two guidewire strategies for angioplasty of chronic total coronary occlusion. Am J Cardiol 2000; 85:1144-7, A9. [PMID: 10781769 DOI: 10.1016/s0002-9149(00)00713-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Chronic total coronary occlusions were more frequently crossed using the Crosswire as a primary guidewire strategy than with the conventional strategy. This strategy resulted in a lower number of guidewires being used, a trend toward shorter procedural and fluoroscopy times, and decreased use of contrast media.
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80
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Dumas P, Sun Y, Corbeil G, Tremblay S, Pausova Z, Kren V, Krenova D, Pravenec M, Hamet P, Tremblay J. Mapping of quantitative trait loci (QTL) of differential stress gene expression in rat recombinant inbred strains. J Hypertens 2000; 18:545-51. [PMID: 10826556 DOI: 10.1097/00004872-200018050-00006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE Stress has been shown to be a major environmental contributor to cardiovascular diseases through its effects on blood pressure variability and cardiac function. The cellular stress response is characterized by the expression of specific heat stress genes (hsps), under the transcriptional control of heat shock transcription factors (HSTFs). The levels of hsp mRNA depend on the severity of the stress, with hstf1 acting as a stress sensor. The aim of this work was to evaluate the genetic contribution of the variability in hsp expression, and to identify its putative quantitative trait loci (QTL). METHODS Twenty recombinant inbred rat strains (RIS) were studied. The animals underwent a standardized, identical 1 h immobilization stress in restraint cages, followed by 1 h of rest before sacrifice. Total RNA was extracted from the heart kidneys and adrenals, and the mRNA levels of hsp27, hsp70, hsp84, hsp86 and hsp105 were measured. The strain distribution pattern (SDP) of hsp expression was correlated with that of 475 polymorphic markers distributed throughout the RIS genome. A polymorphism of rat hstf1 in RIS was used for its mapping in RIS. RESULTS Despite an identical stress being applied to all strains, hsp expression showed up to a 1 2-fold gradient with little intra-strain variability, indicative of a strong genetic contribution to the trait Heritability ranged from 50 to 77% for most hsp genes in the three target organs. The continuous SDP of stress gene expression indicated the polygenic nature of the trait A common locus on chromosome 7 (at D7Cebrp187s3 marker) was consistently associated with all hsp expression in most of the organs [with a likelihood of odds (LOD) score of 3.0 for hsp27 expression]. We have mapped rat hstf1 on chromosome 7 at the same locus. Finally, the D4Mit19 marker was significantly associated with hsp84 expression in the heart (LOD score of 3.1). CONCLUSION Two loci were linked with the differential expression of HSPs in response to immobilization stress in target organs of RIS. The chromosome 7 locus unveiled for all HSPs could explain up to 42% of the observed inter-strain variability of hsp levels in response to stress. We propose hstf1 as a positional candidate at this locus.
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MESH Headings
- Adrenal Glands/metabolism
- Animals
- Base Sequence
- Chromosome Mapping
- Crosses, Genetic
- DNA Primers/genetics
- Gene Expression
- Heat-Shock Proteins/genetics
- Kidney/metabolism
- Male
- Myocardium/metabolism
- Polymorphism, Genetic
- Quantitative Trait, Heritable
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred BN
- Rats, Inbred SHR
- Recombination, Genetic
- Stress, Physiological/genetics
- Stress, Physiological/metabolism
- Transcription Factors/genetics
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81
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Cowley AW, Stoll M, Greene AS, Kaldunski ML, Roman RJ, Tonellato PJ, Schork NJ, Dumas P, Jacob HJ. Genetically defined risk of salt sensitivity in an intercross of Brown Norway and Dahl S rats. Physiol Genomics 2000; 2:107-15. [PMID: 11015589 DOI: 10.1152/physiolgenomics.2000.2.3.107] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A genetic segregation analysis was performed to identify genes that cosegregate with arterial blood pressure traits reflective of salt sensitivity. A population of 113 F2 male rats was derived from an intercross of inbred SS/JrHsd/Mcw (Dahl salt-sensitive) and BN/SsN/Mcw (Brown Norway) rats. Rats were maintained on an 8% salt diet from the age of 9 to 13 wk, and arterial pressure was measured for 3 h daily during the 4th wk of high salt intake in unanesthetized rats using implanted arterial catheters. At the end of the 3rd day of high-salt pressure recordings, the arterial pressure response to salt depletion was determined 1.5 days following treatment with Lasix and a low-sodium (0. 4%) diet. A genome-wide scan using 265 polymorphic simple sequence length polymorphism (SSLP) markers found that seven arterial pressure phenotypes determined at different times and circumstances, and representing two distinct indexes of salt sensitivity, mapped to the same region of rat chromosome 18. The trait of salt sensitivity was strongly influenced by the presence of SS alleles in this region of chromosome 18, and those rats which were homozygote SS/SS exhibited a significantly greater reduction of mean arterial pressure following sodium depletion (29 +/- 2 mmHg) than homozygote BN/BN (17 +/- 3 mmHg) or heterozygotic (22 +/- 2 mmHg) rats. This region of rat chromosome 18 corresponds to the long arm of human chromosome 5 and a region of human chromosome 18 that has been linked to hypertension in humans. Given the unlikely chance of these different blood pressure traits mapping to the same region, we believe these data provide evidence that this region of rat chromosome 18 plays an important role in salt-induced hypertension.
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82
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Nikulin A, Serganov A, Ennifar E, Tishchenko S, Nevskaya N, Shepard W, Portier C, Garber M, Ehresmann B, Ehresmann C, Nikonov S, Dumas P. Crystal structure of the S15-rRNA complex. NATURE STRUCTURAL BIOLOGY 2000; 7:273-7. [PMID: 10742169 DOI: 10.1038/74028] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In bacterial ribosomes, the small (30S) ribosomal subunit is composed of 16S rRNA and 21 distinct proteins. Ribosomal protein S15 is of particular interest because it binds primarily to 16S rRNA and is required for assembly of the small subunit and for intersubunit association, thus representing a key element in the assembly of a whole ribosome. Here we report the 2.8 ¿ resolution crystal structure of the highly conserved S15-rRNA complex. Protein S15 interacts in the minor groove with a G-U/G-C motif and a three-way junction. The latter is constrained by a conserved base triple and stacking interactions, and locked into place by magnesium ions and protein side chains, mainly through interactions with the unique three-dimensional geometry of the backbone. The present structure gives insights into the dual role of S15 in ribosome assembly and translational regulation.
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MESH Headings
- Amino Acid Sequence
- Base Pairing/drug effects
- Base Pairing/genetics
- Base Sequence
- Binding Sites/drug effects
- Conserved Sequence/genetics
- Crystallography, X-Ray
- Magnesium/pharmacology
- Models, Molecular
- Molecular Sequence Data
- Nucleic Acid Conformation/drug effects
- Protein Conformation
- RNA, Bacterial/chemistry
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- RNA, Ribosomal, 16S/chemistry
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 16S/metabolism
- Ribosomal Proteins/chemistry
- Ribosomal Proteins/metabolism
- Structure-Activity Relationship
- Thermus thermophilus/chemistry
- Thermus thermophilus/genetics
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83
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Lefèvre T, Louvard Y, Morice MC, Dumas P, Loubeyre C, Benslimane A, Premchand RK, Guillard N, Piéchaud JF. Stenting of bifurcation lesions: classification, treatments, and results. Catheter Cardiovasc Interv 2000. [PMID: 10700058 DOI: 10.1002/(sici)1522-726x(200003)49:3<274::aid-ccd11>3.0.co;2-n] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Percutaneous transluminal balloon coronary angioplasty (PTCA) of coronary bifurcations is associated with a low success rate, high rate of complications, and high incidence of target vessel revascularization (TVR). The strategy of systematic coronary stenting in bifurcation lesions involving a side branch >/= 2.2 mm in diameter was prospectively evaluated in a single-center observational study during a 35-month inclusion period. All patients meeting these criteria were consecutively included. Bifurcation lesions and treatment were predefined in the study. The study included 366 patients (12.1% of PTCA) with 373 bifurcation lesions, mean age 63.7 +/- 11.6 years, 79.2% male, 46.7% with unstable angina, and 8.3% acute MI. The left anterior descending/diagonal bifurcation was involved in 55.2% of cases, circumflex/marginal 22. 2%, PDA/PLA 10.4%, left main bifurcation in 6.8%, and others 5.4%. The main branch (2.78 +/- 0.42 mm reference diameter) was stented in 96.3% of cases and the side branch (2.44 +/- 0.43 mm) in 63.2% (the two branches were stented in 59.5% of cases). Procedural success was obtained in 96.3% in both branches and 99.4% in the main branch. At1-month follow-up, The major cardiac event rate (MACE) was 4.8% (death 1.1%, emergency CABG 0.6%, Q-wave MI 0.9%, acute or subacute closure 1.4%, repeat PTCA 1.1%, and non-Q-wave MI 2.3%). At 7-month follow-up, the total MACCE rate was 21.6%, including a TVR rate of 17.2%. Analysis of the 7-month outcome according to two study periods (period I, 1 January 1996 to 31 August 1997, 182 patients; period II, 1 September 1997 to 30 June 1998, 127 patients) showed that the TVR rate decreased from 20.6% to 13.8% (P = 0.04) and the MACE rate from 29.2% to 17.1% (P < 0.01) in period I and II, respectively. This was associated by univariate analysis with an increasing use of tubular stents deployed in the main branch (94.2% vs. 59.1%, P < 0.001) and kissing balloon inflation after coronary stenting (75.4% vs. 18.1%, P < 0.001). Bifurcation lesions are frequent. Procedural success of coronary stenting is high with a low rate of in-hospital MACE. TVR rate at follow-up is relatively low. In-hospital and follow-up results are influenced not only by the learning curve but also by the use of tubular stents in the main branch and final kissing balloon inflation.
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84
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Levallois P, Ayotte P, Louchini R, Desrosiers T, Baribeau H, Phaneuf D, Gingras S, Dumas P, Zee J, Poirier G. Sources of nitrate exposure in residents of rural areas in Quebec, Canada. JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY 2000; 10:188-95. [PMID: 10791599 DOI: 10.1038/sj.jea.7500079] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
Nitrate exposure was investigated in a group of 187 people using well water and living in four areas of rural Quebec (Canada) with intensive agricultural activities. Nitrate intake was evaluated using a 24-h dietary recall and a food frequency questionnaire, in conjunction with a validated food database and measurements of nitrate concentrations in private wells. The total internal dose was estimated by means of the 24-h urinary nitrate excretion, while taking into account risk factors for endogenous nitrate formation. Mean (geometric) 24-h urinary nitrate excretion was 16.9 mg N for the 100 people with low groundwater contamination (mean nitrate concentration=0.18 mg N/l) and 23.3 mg N in the 87 individuals with moderate groundwater contamination (mean nitrate concentration=7.1 mg N/l). A multivariate analysis revealed that dietary nitrate intake during the last 24 h was the principal source of exposure, followed by water intake during the last 24 h. The Quetelet index was also a significant predictor of urinary excretion. The total predictive model explained only 29% of the variability in urinary nitrate excretion (R2=0.286). Neither the inflammatory status as indicated by elevated C reactive protein, the presence of Helicobacter pylori antibodies nor the occurrence of diarrhea during the last 24 h prior to urine collection were associated with urinary nitrate excretion. In conclusion, food and to a lesser extent water contribute to nitrate exposure in this rural setting with moderate water contamination. Better predictors of endogenous nitrate production are needed to improve our ability to model nitrate body burden and estimate associated health risks.
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85
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Lefèvre T, Louvard Y, Morice MC, Dumas P, Loubeyre C, Benslimane A, Premchand RK, Guillard N, Piéchaud JF. Stenting of bifurcation lesions: classification, treatments, and results. Catheter Cardiovasc Interv 2000; 49:274-83. [PMID: 10700058 DOI: 10.1002/(sici)1522-726x(200003)49:3<274::aid-ccd11>3.0.co;2-n] [Citation(s) in RCA: 297] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Percutaneous transluminal balloon coronary angioplasty (PTCA) of coronary bifurcations is associated with a low success rate, high rate of complications, and high incidence of target vessel revascularization (TVR). The strategy of systematic coronary stenting in bifurcation lesions involving a side branch >/= 2.2 mm in diameter was prospectively evaluated in a single-center observational study during a 35-month inclusion period. All patients meeting these criteria were consecutively included. Bifurcation lesions and treatment were predefined in the study. The study included 366 patients (12.1% of PTCA) with 373 bifurcation lesions, mean age 63.7 +/- 11.6 years, 79.2% male, 46.7% with unstable angina, and 8.3% acute MI. The left anterior descending/diagonal bifurcation was involved in 55.2% of cases, circumflex/marginal 22. 2%, PDA/PLA 10.4%, left main bifurcation in 6.8%, and others 5.4%. The main branch (2.78 +/- 0.42 mm reference diameter) was stented in 96.3% of cases and the side branch (2.44 +/- 0.43 mm) in 63.2% (the two branches were stented in 59.5% of cases). Procedural success was obtained in 96.3% in both branches and 99.4% in the main branch. At1-month follow-up, The major cardiac event rate (MACE) was 4.8% (death 1.1%, emergency CABG 0.6%, Q-wave MI 0.9%, acute or subacute closure 1.4%, repeat PTCA 1.1%, and non-Q-wave MI 2.3%). At 7-month follow-up, the total MACCE rate was 21.6%, including a TVR rate of 17.2%. Analysis of the 7-month outcome according to two study periods (period I, 1 January 1996 to 31 August 1997, 182 patients; period II, 1 September 1997 to 30 June 1998, 127 patients) showed that the TVR rate decreased from 20.6% to 13.8% (P = 0.04) and the MACE rate from 29.2% to 17.1% (P < 0.01) in period I and II, respectively. This was associated by univariate analysis with an increasing use of tubular stents deployed in the main branch (94.2% vs. 59.1%, P < 0.001) and kissing balloon inflation after coronary stenting (75.4% vs. 18.1%, P < 0.001). Bifurcation lesions are frequent. Procedural success of coronary stenting is high with a low rate of in-hospital MACE. TVR rate at follow-up is relatively low. In-hospital and follow-up results are influenced not only by the learning curve but also by the use of tubular stents in the main branch and final kissing balloon inflation.
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86
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Dumas P, Pausová Z, Kren V, Krenová D, Pravenec M, Dumont M, Ely D, Turner M, Sun Y, Tremblay J, Hamet P. Contribution of autosomal loci and the Y chromosome to the stress response in rats. Hypertension 2000; 35:568-73. [PMID: 10679499 DOI: 10.1161/01.hyp.35.2.568] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Stress is a critical contributor to cardiovascular diseases through its impact on blood pressure variability and cardiac function. Familial clustering of reactivity to stress has been demonstrated in human subjects, and some rodent models of hypertension are hyperresponsive to stress. Therefore, the present study was designed to uncover the genetic determinants of the stress response. We performed a total genome linkage search to identify the loci of the body temperature response to immobilization stress in a set of recombinant inbred strains (RIS) originating from reciprocal crosses of spontaneously hypertensive rats (SHR) with a normotensive Brown Norway Lx strain. Two quantitative trait loci (QTLs) were revealed on chromosomes (Chrs) 10 and 12 (logarithm of odds scores, 2.2 and 1. 3, respectively). The effects of these QTLs were enhanced by a high sodium diet (logarithm of odds scores, 4.0 and 3.3 for Chrs 10 and 12, respectively), which is suggestive of a salt-sensitive component for the phenotype. Congenics for Chr 10 confirmed both the QTL and the salt effect in RIS. Negatively associated loci were also identified on Chrs 8 and 11. Interaction between the loci of Chrs 10 and 12 was demonstrated, with the rat strains bearing SHR alleles at both loci having the highest thermal response to stress. Furthermore, the Y Chr of SHR origin enhanced the response to immobilization stress, as demonstrated in 2 independent models, RIS and Y Chr consomics. However, its full effect requires autosomes of the SHR strain. These findings provide the first evidence for the genetic determination of reactivity to stress with interactions between autosomal loci and between the Y and autosomal Chrs that contribute to the explanation of the 46% of variance in the stress response.
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87
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Loubeyre C, Premchand RK, Lefèvre T, Louvard Y, Dumas P, Piechaud JF, Lanore JJ, Porta MC, Capitani GA, Morice MC. [Immediate revascularization by angioplasty and coronary stents in patients over age 80 with myocardial infarction]. ARCHIVES DES MALADIES DU COEUR ET DES VAISSEAUX 2000; 93:21-6. [PMID: 11227714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The aim of this study was to assess the results of revascularisation by angioplasty and stenting in octogenarians in the acute phase of myocardial infarction. One hundred and four patients over 80 years of age were identified between January 1995 and April 1995 out of 906 patients admitted within 24 hours of the onset of myocardial infarction. The average age was 85 +/- 4 years with a female predominance (63.4%) and a high incidence of cardiogenic shock (28.8%). Ninety eight patients underwent angioplasty with coronary stenting in 81 patients (82.6%) within 39 +/- 35 min of hospital admission. A primary success was obtained in 96% of cases with restitution of TIMI 3 flow in 83.6% of cases. Hospital mortality was 26.5%, highly influenced by the presence of cardiogenic shock (60.7% versus 12.8% without shock). Univariate analysis showed cardiogenic shock (p < 0.0001) and ejection fraction (p = 0.009) to be predictive of mortality, and a tendency in favour of TIMI 3 flow (p = 0.07) and stent implantation (p = 0.09). Complications were rare: 1% of minor cerebrovascular accidents and 4% of vascular complications. There were no cases of emergency bypass surgery and only one patient had a recurrence of ischaemia at 30 days. The authors conclude that the results at 1 month in a high risk group of octogenarians seem to be in favour of an invasive management with coronary stenting in the acute phase of myocardial infarction.
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88
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Dumas P, Carr GL, Williams GP. Enhancing the lateral resolution in infrared microspectrometry by using synchrotron radiation: applications and perspectives. ACTA ACUST UNITED AC 2000. [DOI: 10.1051/analusis:2000280068] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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89
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Ennifar E, Yusupov M, Walter P, Marquet R, Ehresmann B, Ehresmann C, Dumas P. The crystal structure of the dimerization initiation site of genomic HIV-1 RNA reveals an extended duplex with two adenine bulges. Structure 1999; 7:1439-49. [PMID: 10574792 DOI: 10.1016/s0969-2126(00)80033-7] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND An important step in retroviral replication is dimerization of the genomic RNA prior to encapsidation. Dimerization is initiated by the formation of a transient 'kissing-loop complex' that is thought to be subsequently matured into an extended duplex by the nucleocapsid protein (NCp). Although chemical probing and nuclear magnetic resonance spectroscopy have provided insight into the structure of the kissing-loop structure, no structural information concerning the extended-duplex state is available so far. RESULTS The structure of a minimal HIV-1 RNA dimerization initiation site has been solved at 2.3 A resolution in two different space groups. It reveals a 22 base pair extended duplex with two noncanonical Watson-Crick-like G-A mismatches, each adjacent to a bulged-out adenine. The structure shows significant asymmetry in deep groove width and G-A base-pair conformations. A network of eight magnesium cations was clearly identified, one being unusually chelated by the 3' phosphate of each bulge across an extremely narrowed deep major groove. CONCLUSIONS These crystal structures represent the putative matured form of the initial kissing-loop complex. They show the ability of this self-complementary RNA hairpin loop to acquire a more stable extended duplex structure. Both bulged adenines form a striking 'base grip' that could be a recognition signal, either in cis for another viral RNA sequence, or in trans for a protein, possibly the NCp. Magnesium binding might be important to promote and stabilize the observed extrahelical conformation of these bulges.
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90
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d'Amato T, Dumas P, Saoud M, Mandran M. [Interdependence of positive, negative and depressive symptoms in the course of schizophrenia without psychotic antecedents]. L'ENCEPHALE 1999; 25 Spec No 4:25-8. [PMID: 10609107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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91
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Kim YH, Ajani JA, Carrasco CH, Dumas P, Richli W, Lawrence D, Chuang V, Wallace S. Selective hepatic arterial chemoembolization for liver metastases in patients with carcinoid tumor or islet cell carcinoma. Cancer Invest 1999; 17:474-8. [PMID: 10518191 DOI: 10.3109/07357909909032856] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In many patients with liver metastases from islet cell or carcinoid tumor, vascular occlusion therapy results in prolonged control of symptoms, biochemical response, and also tumor regression. Chemotherapy agents were added to evaluate safety and efficacy. Thirty patients with liver metastases from either carcinoid tumor or islet cell carcinoma underwent sequential vascular occlusion therapy combined with chemotherapeutic agents. In patients with carcinoid tumor, a combination of cisplatin (150 mg) and doxorubicin (50 mg) was used. In patients with islet cell carcinoma, a combination of 5-fluorouracil (350 mg) and streptozotocin (1000-2000 mg) was used. Sixteen patients had carcinoid tumor and 14 had islet cell carcinoma. Biochemical response was observed in 12 of 16 (75%) carcinoid patients and 9 of 10 (90%) islet cell patients. The overall partial response rate was 37% (11/30 patients). Partial response occurred in 4 of 16 (25%) patients with carcinoid tumor and 7 of 14 (50%) with islet cell carcinoma. The median duration of partial responses was 24 months (range, 6-63+ months). The median survival of all patients was 15 months (range, 2-67+ months). No treatment-related deaths occurred. Our data suggest that the addition of these chemotherapeutic agents to vascular occlusion, although safe, has no additional benefit.
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92
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Dumas P, Bergdoll M, Masson J. Comments on the paper by kumagai, hibino, kawano and sugiyama (1999) FEBS lett. 450, 227-230. FEBS Lett 1999; 459:282-3;discussion 284. [PMID: 10518036 DOI: 10.1016/s0014-5793(99)01206-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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93
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Kumar Premchand R, Lefèvre T, Louvard Y, Loubeyre C, Dumas P, Piéchaud JF, Morice MC. Short- and long-term outcome of balloon angioplasty for compromised side branches after intracoronary stent deployment. Catheter Cardiovasc Interv 1999; 48:238-40. [PMID: 10506792 DOI: 10.1002/(sici)1522-726x(199910)48:2<238b::aid-ccd29>3.0.co;2-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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94
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Pezzano M, Duterque M, Lardoux H, Louvard Y, Morice MC, Lefèvre T, Dumas P, Wetterwald E. [Thoracic radiodermatitis in interventional cardiology. Apropos of 6 cases]. ARCHIVES DES MALADIES DU COEUR ET DES VAISSEAUX 1999; 92:1197-204. [PMID: 10533668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
The aim of this study is to describe thoracic radiodermatitis, a rare but not to be forgotten complication of interventional cardiology. The appearances are variable, from often oval-shaped erythema to cutaneous necrosis, with risk of chronic ulceration and malignant degeneration. The authors report 6 cases observed in 1997 after coronary angioplasty. Complex and long procedures are the main causes of this complication. Prevention requires a contribution from all the medical cardiological team, for the diagnosis, determining the indication of the type of revascularisation and for limiting the dose of X-radiation administered.
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95
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Dumas P, Saoud M, Gutknecht C, Dalery J, d'Amato T. [French translations and adaptations of questionnaires of magical thinking (MIS, Eckblad and Chapman, 1983) and perception disorders (PAS, Chapman et al., 1978)]. L'ENCEPHALE 1999; 25:422-8. [PMID: 10598305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Meehl used the term "schizotype" to refer to individuals who possess an underlying vulnerability for schizophrenia. Because of the extremely varying degrees of the schizotype's clinical expression, he recommended assessing schizotypic signs through objective measures rather than clinical judgement. In this way, Chapman et al. have developed symptom-oriented scales based on Meehl's manual, such as the Social Anhedonia (SA) and Physical Anhedonia (PhA) Scales, the Magical Ideation Scale (MIS), the Perceptual Aberration Scale (PAS) and the Impulsive Nonconformity Scale (IN). Whereas Chapman's scales of psychosis proneness are the most internationally used instruments for the assessment of schizotypy, some of them, such as MIS and PAS, were still not available in French. Therefore, the first aim of this report was to offer French translations of the Magical Ideation and the Perceptual Aberration Scales; the agreement of the original authors were obtained for both translated versions and their back translations. The second aim of our study was to establish French norms for each of these scales. The preliminary norms presented here [MIS: 19/30 (for females) and 20/30 (for males); PAS: 18/35 (for both genders)] were obtained by administering both scales to a sample of 134 French students. They are very close to those found by Chapman et al. for University of Wisconsin undergraduate students. We will confirm them with a larger sample of French students.
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Ajani JA, Mansfield PF, Lynch PM, Pisters PW, Feig B, Dumas P, Evans DB, Raijman I, Hargraves K, Curley S, Ota DM. Enhanced staging and all chemotherapy preoperatively in patients with potentially resectable gastric carcinoma. J Clin Oncol 1999; 17:2403-11. [PMID: 10561303 DOI: 10.1200/jco.1999.17.8.2403] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
PURPOSE Patients with local-regional gastric carcinoma have a low rate of curative resection (R0) because of the advanced stage at diagnosis and suboptimal clinical staging. This study was designed to improve clinical staging with the use of laparoscopy and endoscopic ultrasonography (EUS) and to improve R0 resection rates and tolerance by delivering all chemotherapy preoperatively in patients with potentially resectable gastric carcinoma. PATIENTS AND METHODS All patients with histologic proof of localized adenocarcinoma of the stomach underwent a staging laparoscopy before registration. EUS was performed when feasible. The intention was to administer up to five courses of preoperative chemotherapy consisting of fluorouracil (500 mg/m(2)/d as a continuous infusion on days 1 through 5 and as a bolus on days 12 and 19), interferon alfa-2b (3 million units subcutaneously three times a week for 3 weeks), and cisplatin (15 mg/m(2)/d as a bolus on days 1 through 5). After chemotherapy, surgery was attempted to remove the primary and regional lymph nodes. Clinical response and EUS staging were correlated with surgical pathology. The feasibility of this approach, resection rates, patient survival, and patterns of failure also were assessed. RESULTS All 30 patients enrolled were assessed for toxicity, response, and survival. Nineteen men and 11 women were enrolled. The median number of courses delivered per patient was three (range, one to five courses). Fourteen patients (47%) received all five preoperative courses of chemotherapy. The overall clinical response rate was 34%. Twenty-nine patients (97%) underwent attempted resection. Twenty-five (83%) had an R0 resection. Two patients (7%) had no evidence of carcinoma in the surgical specimen, and three had only microscopic carcinoma (>/= 90% necrosis). Posttreatment EUS findings did not correlate well with surgical pathology. The median duration of follow-up was 30 months (range, 5 months to 65+ months). The median survival time for 30 patients, calculated by the Kaplan-Meier method, was 30 months (range, 5 months to 65+ months). There were no cases of grade 4 toxicity. CONCLUSION It is feasible to administer prolonged preoperative therapy in patients with potentially resectable gastric carcinoma. Enhanced staging with laparoscopy and EUS helped in proper selection of patients and better characterization of the stage.
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97
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Nguyen RC, Leclerc JE, Nantel A, Dumas P, LeBlanc A. Argyremia in septal cauterization with silver nitrate. THE JOURNAL OF OTOLARYNGOLOGY 1999; 28:211-6. [PMID: 10461258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
OBJECTIVE The purpose of this study was to demonstrate silver absorption in blood and hair specimens after septal cauterization with silver nitrate and to discuss the potential toxicity of silver. METHOD A prospective study of 11 volunteers without any known occupational exposure to silver products or past history of septal cauterization with silver nitrate was undertaken. Subjects were recruited in an academic tertiary care centre from October 1996 to September 1997. The study population consisted of five patients with anterior epistaxis and six healthy volunteers without any bleeding problem. Cauterization was done with one or two silver nitrate applicators directly on the bleeding vessel or Kiesselbach's area. Blood was sampled before cauterization and at specified times after application, while hair strands were sampled only 3 months later. Measurements of silver concentration in whole blood and in hair segments were obtained by inductively coupled plasma mass spectrometry. RESULTS Silver concentrations in whole blood increased significantly after cauterization (p = .02). The measured peak level seemed to correlate with the number of applicators used. No significant increase in silver concentration was observed in hair samples. CONCLUSIONS Effective silver absorption occurs with only one or two silver nitrate applicators. Hair has not been as reliable as whole blood to document an acute and fragmentary exposure. The indiscriminate use of silver nitrate is a potential source of silver intoxication.
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Thomas E, Dumas P, Ajani JA. Oral etoposide for patients with advanced adenocarcinoma of the pancreas. Invest New Drugs 1999; 16:333-5. [PMID: 10426667 DOI: 10.1023/a:1006113421167] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE Oral etoposide has been shown to be effective against some solid tumor types. This phase II study examined the efficacy of oral etoposide in patients with untreated advanced adenocarcinoma of the pancreas. METHODS AND PATIENTS Previously untreated patients with measurable unresectable or metastatic disease were eligible for inclusion in this study. They were required to have a Zubrod performance status of < or = 2 and normal hematological, renal, and hepatic functions. Written informed consent was obtained from all patients. The etoposide dose was 50 mg/m2/d given orally daily for 21 days with a 7-day rest period and was adjusted based on toxicity. Response was assessed after two courses of therapy. RESULTS Eighteen patients were enrolled and fourteen were evaluable for toxicity and response. Twelve patients developed progressive disease while two patients had only a minor response. The median number of courses was 2 (range, 1-4) and there were 29 total courses delivered. The median survival was 3.5 months (range, 1.6-25.9). There were no treatment-related deaths. Toxicity was moderate. CONCLUSIONS Oral etoposide is not effective against advanced adenocarcinoma of the pancreas.
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Dumas P, Rosenfeld F, Saoud M, Dalery J, d'Amato T. [Translation and French adaptation of the Raine Schizotypal Personality Questionnaire]. L'ENCEPHALE 1999; 25:315-22. [PMID: 10546087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Most of existing self-report measures of schizotypal personality assess only few of the nine traits of schizotypal personality disorder according to DSM III-R or DSM IV. Adrian Raine has developed a self-report scale named "Schizotypal Personality Questionnaire, [SPQ]" to evaluate all these traits. The questionnaire was found to have high sampling validity, high internal reliability [0.91] and test-retest reliability [0.82]. However, the SPQ was still not available in French. Therefore, the first purpose of this report was to offer a French translation of this tool with the agreement of A. Raine for both translated version and its back translation. The second purpose of our study was to establish French norms. The preliminary norms presented here were obtained by administering the SPQ to a sample of 134 French students of both gender (mean age: 20.11 +/- 1.53 years; mean educational level: 13.39 +/- 1.04 years). On that sample, the minimal score was 2/74 and the maximal one 54/74 (mean of the sample: 23.60 +/- 12.09). With the original English study, based on a sample of American students, the cut-offs for the top and the bottom ten percents of SPQ scores were respectively of 41/74 and 12/74. Very close preliminary cut-offs were observed in our own study i.e. respectively 40/74 and 9/74. We will confirm them in a larger sample.
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Partyka S, Dumas P, Ajani J. Combination chemotherapy with granulocyte-macrophage-colony stimulating factor in patients with locoregional and metastatic gastric adenocarcinoma. Cancer 1999; 85:2336-9. [PMID: 10357402 DOI: 10.1002/(sici)1097-0142(19990601)85:11<2336::aid-cncr6>3.0.co;2-i] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND A combination of etoposide, 5-fluorouracil, and folinic acid (ELF) remains popular for the treatment of patients with gastric carcinoma and has been reported to result in a response rate of up to 40% with good patient tolerance. The authors elected to add granulocyte-macrophage-colony stimulating factor (GM-CSF) to ELF to determine whether the response rate could be increased in patients with untreated advanced gastric carcinoma. METHODS Previously untreated patients with measurable metastatic tumor were studied. Outpatient therapy was comprised of etoposide, 120 mg/m2 intravenously (i.v.), on Days 1-3; 5-fluorouracil, 500 mg/m2 i.v., on Days 1-3; and folinic acid, 300 mg/m2 i.v., on Days 1-3. Courses were repeated every 21 days. GM-CSF (at a dose of 250 microg/m2/day for 14 days from Day 4) was added after the first course of ELF if patients developed Grade 4 neutropenia in a previous course. RESULTS Thirty patients were enrolled and 29 were evaluable for response. Four patients (14%) achieved a partial response (median duration of response, 6.5 months). The median duration of survival was 7.8 months. Grade 4 neutropenia occurred in 16 patients who then received GM-CSF. A similar rate of neutropenic fever was observed in courses both with or without GM-CSF (15% in courses without GM-CSF and 16% in courses with GM-CSF); however, a higher nadir absolute granulocyte count (1300 cells/microL) occurred in courses with GM-CSF compared with courses without GM-CSF (300 cells/microL). CONCLUSIONS The ELF regimen resulted in a much lower response rate than reported in the literature. The attempt to improve the efficacy of this regimen by the addition of GM-CSF did not prove successful. The authors believe this regimen cannot be recommended for the treatment of patients with advanced gastric carcinoma outside of a protocol setting.
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