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P Beaufils

Publications and source records attributed to P Beaufils.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Fracture of the great trochanter treated by dynamic hip screw plate: measure of impaction according to fracture type].

INTRODUCTION: The sliding plate has appeared to be a reliable answer for trochanteric fractures. However, impaction allowed by the material may, have an adverse effect (medialisation, shortening, jutting out of the lag screw). The aim of our study was to measure the sliding of the screw in order to assess the impaction in various types of fracture, according to the Ender classification. MATERIAL AND METHODS: Hundred trochanteric fractures have been treated between 1991 and 1993. Eighty four have been analyzed with a follow-up of three months after surgery. The average age was 80.1 years with a 4.2 sex ratio (16 males). One hundred and thirty five degrees free sliding plates were employed for fracture fixation. Full weight bearing was allowed in 78.6 per cent of patients. According to Ender classification, 35 per cent of fractures were type 1, 4 or 5. This was the first group. The second group consisted of types 2 and 3 and the third group of types 6, 7 and 8. The results were assessed on AP and lateral X-rays. The ratio between screw thread length (constant) and screw outside the barrel length, was used to measure impaction on AP view. Osteoporosis was evaluated according to Singh. RESULTS: Despite two screw protrusions out of the femoral head and two failures of the plate, we have observed a healing rate of 100 per cent after three months. Sliding averaged 6.2 mm in group 1, 10.5 mm in group 2 and 16.4 mm in groupe 3. Weight bearing had a low influence on the amount of sliding. DISCUSSION: Group 1 consists of fractures (types 1, 4 and 5) which are two parts fractures considered as stable. Group 2 corresponds to types 2 and 3 considered as intermediate fractures with relative stability. In group 3 (types 6, 7 and 8) we have observed major fracture instability. Osteoporosis does not seem to be the major factor regarding screw sliding. CONCLUSION: The sliding plate is reliable. However, complex fractures healed in a wrong position which is definitely not acceptable, especially for young patients. Therefore, we advise to avoid the use of sliding plate in case of Ender type 6, 7 and 8.

Adult↗
PubMed1997

Qualitatively distinct signaling through T cell antigen receptor subunits.

T cell antigen receptors (TCR) contain several subunits including CD3gamma, delta, and epsilon, and TCRzeta and eta which are capable of mediating signal transduction. It is unclear whether the signaling function of these subunits is completely redundant. To assess the relative signaling capabilities of TCR subunits, we compared proximal events in signal transduction by wild-type TCR complexes and TCR devoid of functional zeta subunits, as well as chimeric receptors containing the cytoplasmic domains of TCRzeta or CD3epsilon. Results demonstrate that in BW5147 wild-type TCR, tail-less zeta TCR, CD3epsilon, and TCRzeta transduce signals leading to tyrosine phosphorylation of similar sets of cellular substrates, including the receptor subunits, Fyn, ZAP-70, and phospholipase Cgamma1 (PLCgamma1). Surprisingly, unlike wild-type TCR, tail-less zeta TCR, and CD3epsilon, TCRzeta was incapable of transducing signals resulting in inositol triphosphate (IP3) generation or intracellular free calcium ([Ca2+]i) mobilization. These data indicate that tyrosine phosphorylation of PLCgamma1 is not sufficient to drive IP3 production and [Ca2+]i mobilization. Most importantly, data presented indicate that TCRzeta and CD3epsilon engage partially distinct signaling pathways.

Amino Acid Sequence↗
PubMed1997

Comparative efficacy of the intravenous administration of linsidomine, a direct nitric oxide donor, and isosorbide dinitrate in severe unstable angina. A French multicentre study. French Group of Investigators.

AIMS: Although linsidomine shares common properties with nitrovasodilators, it releases nitric oxide directly without catalytic involvement by thiols. We conducted a prospective, randomized, multicentre, parallel group, single-blind study to compare the efficacy of intravenous administration of linsidomine with that of isosorbide dinitrate in unstable angina. METHODS AND RESULTS: Between November 1990 and July 1992, 568 patients with suspected unstable angina (class IIIB of the Braunwald classification) received a continuous infusion of either linsidomine (1 mg.h-1 on average) or isosorbide dinitrate (2.5 mg.h-1 on average) for 72 h. All patients received concomitant aspirin and intravenous heparin, 81% beta-blockers and 38% calcium antagonists. Holter monitoring was performed in all patients and analysed blindly. Only 25% of the patients had at least one episode of chest pain during the study (24.6% vs 25.8% in the linsidomine and isosorbide dinitrate groups, P = 0.74), of which 12% were associated with ECG changes. Holter criteria yielded similar results in both groups: 33% of patients presented episodes of myocardial ischaemia (32.6% vs 33.9% in the linsidomine and isosorbide dinitrate groups, P = 0.74), while 45% showed episodes of ventricular arrhythmia (43.5% vs 46.5% in the linsidomine and isosorbide dinitrate groups, P = 0.48). The incidence of serious clinical events at 72 h (death, myocardial infarction or myocardial revascularization) was 6.5% (5% vs 8% in the linsidomine and isosorbide dinitrate groups, P = 0.17). CONCLUSION: Intravenous linsidomine is at least as efficacious as isosorbide dinitrate in the stabilization of patients with severe unstable angina.

Aged↗
PubMed1997

New report of severe coronary artery disease in an eighteen-year-old girl with pseudoxanthoma elasticum. Case report and review of the literature.

An eighteen-year-old woman with pseudoxanthoma elasticum (PXE) suffered from mild angina pectoris over a ten-year period. Severe triple-vessel disease with mild left ventricular dysfunction was demonstrated on angiography. No revascularization was feasible. Despite a reported high frequency of angina pectoris among patients with PXE, only 10 convincing reports have appeared in the literature. Careful coronary artery evaluation is required in young patients with PXE, even though asymptomatic, because coronary artery disease (CAD) seems to be frequent and because no precise feature can be distinguished between types with or without severe vascular disease. Through very rare reports, surgical revascularization appears feasible and beneficial in a less severe form of CAD in patients with PXE. The risk of premature and severe diffuse CAD in PXE does not seem to be explained only by the combination of increased Lp [a] (or any other risk factor) and PXE.

Adolescent↗
PubMed1997

Permanent Electronic Storage of Angiographic Images in the Catheterization Laboratory: High-Resolution and Real-Time Acquisition on Optical Laserdiscs.

The use of electronic ÒfilmlessÓ media for long-term archiving of coronary angiograms has been impeded by the problems of image storage and data transfer among institutions. Although long-term analogue storage of the images is presently feasible, and much less costly than digital storage, processing has been limited to a 625 lines video format, not optimal for high quality images. We developed a bi-directional 1249/625 lines converter, able to store and to replay high resolution (1249 lines) video images, from Component Record Video (CRV) Optical Laser (Analogue) Videodisks. Image quality and medical relevance were evaluated five ways: 1) Outside experts compared 593 static images stored on CRV discs to the same images stored in a high-resolution digital format blinded to source of image. The four experts found no visual or medical difference in 98% of evaluated images and minor differences in the remainder. The differences in the remaining images were not consistent among experts. 2) Two of the experts also compared the enhanced CRV optically stored image to the image obtained on simultaneously recorded 35mm cine film, and found the enhanced CRV stored image to be superior or similar, but never inferior to the film image. 3) 90 representatives from 63 outside institutions compared images from both a digital hard drive and the enhanced CRV optical (analogue) storage displayed at a Windows based digital workstation. During the test they were blinded as to the source of the images. The representatives found no difference in image resolution, quality, diagnostic accuracy, and medical relevance. 4) We evaluated quantitative coronary angiography (QCA) on standard coronary test phantoms using enhanced CRV stored images digitally processed. The correlation of the enhanced CRV image to the actual size of the phantom vessels was similar to the results obtained in the literature from digitally stored images. 5) 78 arterial measurements ranging 0.65 to 4.85 mm were evaluated both from the digital hard disc (D) and the CRV optical disc (CRV), using the same QCA analytical package. The correlation coefficient and the Standard Error of the Estimate between D and CRV values were respectively 0.997 and 0.076, no systematic over or underestimation occurred, and the mean variability was inferior to 0.1 mm. CONCLUSION: High-Resolution CRV-optical storage represents a cost-effective solution for excellent image quality equivalent to digitally stored images, permitting permanent electronic archiving inside the cath-lab, and allowing digital image processing and digital image communication.

Journal Article↗
PubMed1996

[Gleno-humeral arthroscopic arthrolysis for shoulder stiffness. Apropos of 26 cases. Société Française d'Arthroscopie].

UNLABELLED: Shoulder stiffness is a problem which covers many different conditions. In fact there is still a semantic and pathogenetic confusion. The words: capsulite retractile, frozen shoulder, adhesive capsulitis, stiff shoulder contracture have been successively used and this ambiguity renders the literature difficult to interpret. Moreover the cause of the stiffness which depends on the aetiology, is not always clearly known: capsular contraction, capsular adhesion, capsular scarring following trauma or surgery, extra capsular phenomenons in the subacromial bursa, muscles or tendons. MATERIALS AND METHODS: 26 shoulders (25 patients) were reviewed with a follow up of 21 months using the Constant's scoring system. Patients had an average duration of symptoms for 13 months (1 to 27). Pre op passive motion was: abduction: 74 degrees, external rotation: 6 degrees, forward flexion: 84 degrees. The average motion core was 12.9/40. We distinguished three groups: primary frozen shoulder (13 cases) ; bipolar stiffness (3 cases) due to rotator cuff disease ; acquired "surgical" stiffness, (10 cases). The capsular release was performed, at the anterior rim of the glenoid fossa, purely anterior or anterior and inferior, followed by gentle manipulation. If external rotation was not improved the coraco-humeral ligament was detached from its coracoid attachment. Additional procedures were performed:acromioplasty (5 cases), bursectomy (3 cases), SLAP lesion debridement (1 case). Only 2 out 13 primary shoulders required an additional procedure. RESULTS: 1-There were no intra-operative complications (vascular or neural). 2-Range of Motion: the average gain under anesthesia was: abduction: 72 degrees, external rotation: 34 degrees, forward flexion: 86 degrees. Final result was obtained with a mean duration of seven months. There was no difference according to the aetiology. Gain was more important in the primary group (9.69 to 34.9 vs 15.8 to 30.6). 3-Subjective results were better in the primary group. 4-Objective results demonstrated an absolute Constant's score of 70.3, that is to say 83.4 per cent of the contralateral supposed healthy shoulder. There were 3 excellent, 5 very good, 7 good, but 11 fair or poor results. The relative Constant's score was 91 per cent in the primary group and only 76 per cent in the acquired group. The difference was due to the pain and strength which were greatly improved in the primary group. DISCUSSION: Arthroscopic release of shoulder contracture is feasible, safe and effective. For primary frozen shoulder, there is usually spontaneous recovery. Indications for surgery are very few. There is no evidence that arthroscopic release shortens spontaneous evolution. Therefore, we propose it in very selected cases of dramatically limited motion. One year of evolution is an acceptable time. For bipolar stiffnesses, arthroscopy allows one to recognize the exact cause of the stiffness and to treat it, especially the subacromial pathology. In this occurrence, buroscopy must be performed and cuff pathology treated. For acquired surgical stiffnesses, gain of motion is significant. Subjective and objective results are less satisfactory than those of primary frozen shoulder, due to persistance of pain and lack of strength. The alternative is open release, but arthroscopic release has less morbidity. It can be proposed early as soon as capsular tissue has healed (for instance 6 months).

Adult↗
PubMed1995

[Medical treatment of atrial fibrillation in the healthy heart].

Whatever the cause and clinical features, establishing the strategy for the medical treatment of atrial fibrillation, requires three basic steps. First sinus rhythm must be restored, followed by the prescription of antiarrhythmic drugs to prevent recurrence and finally the use of anticoagulants. Obviously the underlying heart disease has a major effect on the patient's tolerance of atrial fibrillation, the risks of peripheral embolism and overall mortality. In patients with "solitary atrial fibrillation" and an apparently normal heart, each step of the treatment must be examined in light of the individual patients clinical situation and the risks of haemorrhage with anticoagulants as well as the risk of lethal ventricular arrhythmia due to the arrhythmogenic effect of class la or 1c antiarrhythmic drugs.

Anti-Arrhythmia Agents↗
PubMed1995

[Gluteal posterior approach for surgery of the acetabulum].

PURPOSE OF THE STUDY: This approach was developed to avoid gluteus maximus muscle injury which is divided when using the common Langenbeck-Kocher approach. The posterior perigluteal approach also provides better visualization of the posterior aspect of the acetabulum. MATERIAL AND METHODS: A semi-circular incision is made from the fascia lata at the anterior aspect of the greater trochanter and then directed to the posterio-superior iliac spine. The gluteus maxirnus is then simply retracted medially with blunt retractors. Sixty eight acetabular fractures have been operated with this approach including both mixed and complex fractures of the posterior column. Occasionally fractures of both columns have been operated in two procedures, one posterior and then a second anterior approach. RESULTS: The posterior perigluteal approach preserves gluteus maximus muscle tone. It seems to avoid post-operative ossification. CONCLUSION: We propose an approach which, compare to the Langenbeck- Kocher approach, is less traumatic, and as easy to perform.

Acetabulum↗
PubMed1994

The SFA system for assessing articular cartilage lesions at arthroscopy of the knee.

We proposed to establish a system of assessing severity of chondropathy taking into account localization, size, and depth of cartilage lesions. The design of the study was prospective and multicenter. The subjects were 755 patients who had undergone arthroscopy of the knee. Criteria for assessment of severity of chondropathy were as follows: (a) Physician's overall assessment using a 100-mm-long Visual Analogue Scale, and (b) size, grade, and localization of cartilage lesions recorded on a diagram. We used multivariate parametric and nonparametric analyses. The analyses resulted in two systems of assessing severity of chondropathy: SFA scoring for the three compartments of the knee, which is a continuous variable, and SFA grading, which is a semiquantitative variable. These systems seem to be of clinical relevance. However, more studies are required to further validate them and their capacity to detect changes in severity of chondropathy.

Adult↗
PubMed1994

[Endoscopic acromioplasty in total rupture of the rotator cuff].

PURPOSE OF THE STUDY: The authors have conducted a study to evaluate the possible efficacy of endoscopic decompression without repair in the treatment of rotator cuff tears. MATERIAL AND METHOD: We report 42 cases of endoscopic acromioplasty realized for full-thickness rotator cuff tears. Mean follow-up was 28.8 months. The principal presenting symptom was pain, with a mean duration of 29 months. Antero-external acromioplasty was realized by endoscopy using motorized drill bits, with sectioning or resecting the acromio-coracoid ligament. Revision consisted of a standard clinical examination, following the protocol of Constant, and a radiologic examination by sub-acromial frontal and scapular profile x-rays as advised by Liotard. RESULTS: The functional results were very good, with 94 per cent of patients satisfied. The mean Constant score was 67.4 (14-100) corresponding on the average to 84 per cent of the score of a healthy shoulder for the same age and sex. The improvement concerned essentially the score of the pain, which increased on the average 7.4 points out of 15 (10.2/15 at revision) and of the activity level (14.8/20 as opposed to 8/20 initially). Less important was the improvement of the active mobility score (from 25.2 to 34/40 at revision). The force was measured according to the Constant scale, with a mean of 8.3 points out of 25. The mean duration of absence from work for the active patients was 2.4 months. Neither infectious nor neurological complications were noted. The radiographic analysis showed a decrease of the acromial edge, significative as compared to the opposite side. On the profile x-ray, we observed 48 per cent flat acromions in contrast to 80 per cent curved types on the opposite side. The only element influencing the pain score was the size of the rupture, but the statistical result was weak. The final Constant score was strongly influenced by by the size of the rupture, the active mobility, the pre-operative active and passive mobility, as well as by the presence of head excentration on pre-operative x-rays. DISCUSSION: Comparison with other series of endoscopic acromioplasty for full-thickness rotator cuff tears has permitted us to confirm the validity of our series. We have especially evaluated this series in comparison to those with surgical repair. The subjective results, as well as those for pain, are equivalent; results on active mobility and force were not as good. We propose, therefore, this technique of low morbidity, in the presence of total ruptures in older and sedentary patients. The antalgic effect of endoscopic acromioplasty allows, in these patients, a functionally satisfying rehabilitation.

Acromion↗
PubMed1994

[Value of searching ventricular late potentials in patients recovering from ventricular fibrillation].

The prognostic value of ventricular late potentials (VLP) was studied in 38 survivors of ventricular fibrillation (VF) resuscitated after cardiac arrest. Thirty-seven patients had coronary artery disease, 24 within one month of myocardial infarction, and one patient had valvular heart disease. There were 7 deaths within 2 years, including 5 sudden deaths, the average follow-up in the remaining patients being 46 +/- 30 months. Bad prognostic factors included low left ventricular ejection fraction, anterior myocardial infarction, VF occurring after the first 24 hours of myocardial infarction and the presence of VLP. The 2 year mortality rate was 35% in patients with VLP compared with only 5% when they were absent (p < 0.05). The subgroup with the highest risk of death was that of anterior myocardial infarcts with VLP (45% 2 year mortality). The clinical circumstances surrounding VF were important; patients with clinical and electrical signs of ischaemia at the time of VF tended to have a better prognosis than the others, especially in the absence of VLP: in this subgroup of 12 "ischaemic" VFs without VLP the mortality at 2 years was nil, whereas the other 26 patients had a 27% death rate (0.05 < p < 0.10). Programmed ventricular stimulation was only carried out in 14 cases: it showed that the long-term mortality was very high (60%) in patients with VLP and inducible ventricular tachycardia (VT). Therefore, the implantation of an automatic defibrillator device would seem to be justified in patients resuscitated from VF who have both VLP and inducible VT, but of no value in cases of "ischaemic" VF without VLP.

Action Potentials↗
PubMed1993

The (YXXL/I)2 signalling motif found in the cytoplasmic segments of the bovine leukaemia virus envelope protein and Epstein-Barr virus latent membrane protein 2A can elicit early and late lymphocyte activation events.

The cytoplasmic domains of the transducing subunits associated with B and T cell antigen receptors contain a common amino acid motif consisting of two precisely spaced Tyr-X-X-Leu/Ile sequences (where X corresponds to a variable residue). Expression of a single copy of this motif suffices to initiate B or T cell activation. The bovine leukaemia virus (BLV) is a B cell lymphotropic retrovirus which causes a non-neoplasic proliferation of B cells. The cytoplasmic domain of the BLV transmembrane envelope glycoprotein, gp30, possesses two overlapping copies of the Tyr-X-X-Leu/Ile-containing motif which could participate in the induction of B cell activation. Similarly, the N-terminal cytoplasmic domain of the latent membrane protein 2A (LMP2A) of the Epstein-Barr virus (EBV) contains a single copy of the Tyr-X-X-Leu/Ile-containing motif which could play a critical role in B cell transformation. To determine whether these two virus-encoded cytoplasmic domains are endowed with signalling functions, we constructed chimeric proteins by replacing the cytoplasmic tail of CD8-alpha with that of either BLV gp30 or EBV LMP2A. We show here that, once separately expressed in B or T cell lines, these chimeras are capable of triggering both calcium responses and cytokine production when cross-linked with an antibody to CD8-alpha. Furthermore, using site-directed mutagenesis, we demonstrated unequivocally that this signalling function may be accounted for by the Tyr-X-X-Leu/Ile motifs they contain.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

Diagnostic and prognostic value of coronary arteriography.

Coronarography can be used as a diagnostic test when the clinical evaluation and the non-invasive test are inconclusive, although some conceptual problems remain. In known ischemic heart disease, the estimation of the prognosis is an important factor for the treatment decision, but coronary arteriography does not give a clear picture, and apart from the most severely ill patient, the prognosis usually remains very difficult to evaluate.

Coronary Angiography↗
PubMed1993

Hemodynamics, tolerability, and pharmacokinetics of linsidomine (SIN-1) infusion during the acute phase of uncomplicated myocardial infarction.

To determine a dose regimen and evaluate the hemodynamic effects of linsidomine administered by continuous intravenous (i.v.) infusion, 10 patients were studied during the acute phase of uncomplicated myocardial infarction (MI). Systolic, diastolic, and mean (SBP, DBP, MBP) systemic blood pressure and heart rate (HR) were measured noninvasively. Pulmonary artery pressures were monitored after insertion of a Swan-Ganz catheter, which also enabled measurement of cardiac output (CO) and cardiac index (CI) by thermodilution. After baseline hemodynamic values (period A) were determined, linsidomine (SIN-1) was infused at a rate of 0.8 mg/h and subsequently adjusted to obtain a 10% decrease in MBP from its baseline value (period B). The infusion was then continued for 3 h at a constant rate (period C), and pressures were monitored for 1 h after the infusion was discontinued (period D). There were no significant changes in systemic or pulmonary arterial pressures or in HR between period B and period C. In contrast, CI decreased moderately (p < 0.05), with no clinical consequences. Return to baseline hemodynamics was obtained at the end of period D. Our findings indicate that continuous i.v. administration of SIN-1 (at a mean flow rate of 1 mg/h) is well tolerated and appears to be suitable for use in acute coronary syndromes.

Adult↗
PubMed1992

Improvement of digital coronary angiography: high resolution processing coupled with a real time functional synchronization procedure.

The use of Digital Subtraction Angiography in coronary applications is restricted by the difficulty in: 1. Obtaining a good resolution of the distal branches. 2. Avoiding, for the purpose of subtraction, the motion artifacts induced by artery and background displacement during the cardiac and respiratory cycles. 3. Preserving the dynamic vascular motion. 4. And storing the digital dynamic information on a permanent support. We used for this study an angiography system, based upon a high resolution 45 MIPS-32 Mbyte image processor, interfaced with a 2.75 Gbyte Winchester drive allowing the real time storage of either 30 frames/s in the 512*512*8 bits matrix or of 7.5 f/s in the 1024*1024*8 bits matrix. To preserve the most important dynamic informations on the basis of the 7.5 f/s maximal storage rate, we developed a synchronization device able to recognize in real time, from chronologic delays derived by using both ECG and Aortic Pressure curves, the functional End-Diastolic (ED) and the End-Systolic (ES) positions, even in the case of heart rates varying during the procedure. The ED and the ES images are stored together with the Mid-Systolic (MS), the 1/3-Diastolic (1/3D) and 2/3-Diastolic (2/3D) images. To establish the validity of this sampling method, which uses a reduced number of frames per cardiac cycle, 7200 coronary injections performed during 450 routine coronary angiographies were compared by two independent observers (A and B), using: first a Digital (D) 5 frames/cycle sequence, and secondly a cine Film (F) 50 frames/s sequence acquired immediately after the corresponding D injection. The D technique resulted in the best image and diagnostic quality, particularly when the F quality was estimated 'fair' or 'poor' by both observers, and in an important reduction on X-Ray doses. The visualisation of the sequential ED, MS, ES, 1/3D and 2/3D frames gives the possibility: 1. of saving the dynamic information, as a regular sample of functional images can be displayed with a cine loop technique. 2. of facilitating cardiac synchronized subtractions. 3. of reducing the amount of frames per cycle, thus allowing an important reduction of X-ray doses and the digital and permanent storage of the most important cardiac cycles.

Angiography, Digital Subtraction↗