Experimental evidence of shock wave measurements with low-velocity (<100 m s-1) and fast dynamics (<10 ns) capabilities using a coupled photonic Doppler velocimetry (PDV) and triature velocity interferometer system for any reflector (VISAR) diagnostic.

We present a series of shock-wave measurements on aluminum based on the use of a simultaneous Photon Doppler Velocimetry (PDV) and triature velocity interferometer system for any reflector. Our dual setup can accurately measure shock velocities, especially in the low-speed range (<100 m s-1) and fast dynamics (<10 ns) where measurements are critical in terms of resolution and unfolding techniques. Especially, the direct comparison of both techniques at the same measurement point helps the physicist in determining coherent settings for the short time Fourier transform analysis of the PDV, providing increased reliability of the velocity measurement with a global resolution of few m s-1 in velocity and few ns FWHM in time. The advantages of such coupled velocimetry measurements are discussed, as well as new opportunities in dynamic materials science and applications.

Hypervelocity impacts into porous graphite: experiments and simulations.

We present experiments and numerical simulations of hypervelocity impacts of 0.5 mm steel spheres into graphite, for velocities ranging between 1100 and 4500 m s-1 Experiments have evidenced that, after a particular striking velocity, depth of penetration no longer increases but decreases. Moreover, the projectile is observed to be trapped below the crater surface. Using numerical simulations, we show how this experimental result can be related to both materials, yield strength. A Johnson-Cook model is developed for the steel projectile, based on the literature data. A simple model is proposed for the graphite yield strength, including a piecewise pressure dependence of the Drucker-Prager form, which coefficients have been chosen to reproduce the projectile penetration depth. Comparisons between experiments and simulations are presented and discussed. The damage properties of both materials are also considered, by using a threshold on the first principal stress as a tensile failure criterion. An additional compressive failure model is also used for graphite when the equivalent strain reaches a maximum value. We show that the experimental crater diameter is directly related to the graphite spall strength. Uncertainties on the target yield stress and failure strength are estimated.This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

[CO2 laser treatment of skin cylindromas in Brooke-Spiegler syndrome]. / Traitement des cylindromes cutanés par laser CO2 dans le syndrome de Brooke-Spiegler.

BACKGROUND: Multiple skin cylindromas are of autosomal dominant transmission and may be associated with spiradenoma and trichoepithelioma. This condition is known as Brooke-Spiegler syndrome. The aim of this study is to compare surgical and laser treatment for these lesions. CASE REPORTS: Five patients from a single family (two male and three female) consulted at the dermatology department for the treatment of multiple cylindromas of the scalp. The female patients presented a more severe form that had developed into "turban tumour". All patients were initially treated by surgery. Two had undergone multiple surgical excisions alone while the others had been treated with CO2 laser. One of the female patients treated with surgery had undergone complete excision of the scalp covered by total skin graft. The three patients treated with CO2 laser were completely satisfied with their therapy, which enabled a larger number of lesions to be treated at each session. They underwent one session every three months under local anaesthesia. CONCLUSION: CO2 laser constitutes an alternative to surgery in the treatment of multiple skin cylindroma. It gives excellent cosmetic result with excellent safety and a high degree of satisfaction among treated patients. It should be proposed for patients refusing surgery or where the number of lesions enables first-line use of this approach to be envisaged.

[Intermediate term outcome in 70 patients with Tako-Tsubo syndromes]. / Devenir à moyen terme de 70 syndromes de Tako-Tsubo.

BACKGROUND: Tako-Tsubo syndrome is a reversible left ventricular myocardial dysfunction. There are few publications on its evolution and the purpose of this study is to describe the medium-term outcome of patients who presented this pathology. METHODS: This retrospective study included 70 patients presenting with Tako-Tsubo syndrome who were referred to Haut-Lévèque hospital between November 2003 and January 2012. The parameters included in follow-up were: number of cardiovascular events, recurrence, electrocardiographic and echocardiographic evolution. RESULTS: Sixty-eight patients had a mean follow-up of 4.8±2.4 years. The survival rate was 92%, 39 patients (57%) showed no cardiovascular symptoms, 12 (18%) had one or more new episodes of chest pain and 4 (6%) had stage II dyspnoea on the NYHA classification scale. One patient had a recurrence 6.5 years later, triggered by the same stress as the first instance. Forty-five patients (64%) had ECGs which evolved in the early days to diffuse T-wave inversion. In the medium term, 32 (54%) patients had a normal ECG, 19 (32%) had inverted T-waves in precordial leads and 2 (3%) had Q-waves. In terms of echocardiography, left ventricular ejection fraction was normal in all with variable delays. Four patients continued to have apical hypokinesia. CONCLUSION: This study shows that the medium-term outlook is favourable in terms of cardiovascular mortality and that recurrence is rare. It highlights, however, the persistence of electrocardiographic and echocardiographic abnormalities.

Conversion to open repair after endovascular aneurysm repair: causes and results. A French multicentric study.

OBJECTIVE: To evaluate the causes and results of conversion to open repair after aortic aneurysm endovascular treatment (EVAR). DESIGN: Retrospective study of open conversion after EVAR was performed in eight French academic centres. Primary conversion (PC) within 30 days after EVAR and secondary conversions (SC) were analysed separately. RESULT: Between 1997 and 2007, open conversions were performed in 34 patients (most often in high-risk patients): 14 PC and 20 SC. Two main causes of PC were unfavourable iliac artery anatomy and renal artery coverage. In hospital mortality was 21%. SC occurred at a median of 44 months after primary EVAR. Nine were urgent cases for rupture or infection and 11 elective for aneurysm growth, infection or thrombosis. Early mortality was similar after emergent or elective SC (25%). CONCLUSION: Open conversion, and, in particular, PC and urgent SC, was associated with a poor outcome. According to the literature, mortality after elective SC is low but remains high in high-risk patients.

Evaluation of a new vascular suture system for aortic laparoscopic surgery: an experimental study on pigs and cadavers.

OBJECTIVES: The aim of this study was to assess the feasibility and efficacy of a new laparoscopic vascular suturing device. METHODS: Animal study: six pigs underwent surgery using a retroperitoneal laparoscopic approach. Aorto-prosthetic side-to-end and end-to-end anastomoses were performed laparoscopically on each pig using SuDyn. Clamping and anastomosis times, as well as the properties of the anastomoses, were recorded. Study on cadavers: four aorto-prosthetic end-to-end anastomoses were performed using the direct transperitoneal laparoscopic approach to assess the feasibility of the SuDyn device on atherosclerotic aortas. RESULTS: Animal study: No pigs died and 12 patent and impermeable anastomoses were obtained. Mean anastomosis time was 38(+/-8)min for end-to-side anastomoses and 37(+/-5)min for end-to-end anastomoses. Study on cadavers: Totally laparoscopic anastomoses were performed in 4 human cadavers with a mean anastomosis time of 37(+/-3)min. CONCLUSIONS: SuDyn makes laparoscopic aorto-prosthetic anastomoses easier to perform, produces good results and does not require a learning curve.

[Transient left ventricular apical ballooning syndrome. Case report and review of the literature]. / Syndrome de ballonisation apicale transitoire du ventricule gauche. Revue de la littérature à propos d'un cas.

SUBJECT: Transient left ventricular apical ballooning syndrome, known as the japanese name of tako-tsubo was recently described and is characterised at the acute period by a large apical dyskinesia of the left ventricule apex. This syndrome usually mimics an acute coronary syndrome, sometime a cardiac failure or arrhythmias. We report a typical case of a seventy-seven years old women struck by a tako-tsubo syndrome revealed by an acute chest pain after an emotional stress. The diagnosis was proposed because angiography didn't shown any abnormality in spite of a large left ventricular dysfunction at the ventriculography. Actuality and strong points: Tako-tsubo syndrome is more and more published due to a better knowledge of this syndrome, specially in the acute coronary syndrome without coronary abnormality. His physiopathology is not well known but is clearly in relation with an acute stress. Several hypothesis are discussed, helped by some experimental animal model. With an excellent prognosis at a middle-course, his discovery allow an adapted take care especially of the complications. PROSPECT: The setting up of clinic and electrocardiographic reliable and well-tried criteria will allowed an early diagnosis to avoid harmful treatment. His specific treatment is not reached by consensus but will develop by a better knowledge of the physiopathology.

The Paget-Schroetter syndrome.

Primary axillo-subclavian venous thrombosis is pathology of the young working man. It affects above all the main upper limb and arises during a physical activity of the shoulder. Its aetiology is complex and multifactorial. It is most often the consequence of a chronic compression of the subclavian vein at the level of the thoracic outlet. Clinical presentation can be confirmed with a duplex scan investigation.Early diagnosis offers the opportunity for rapid venous recanalisation with an anticoagulation treatment. A fibrinolytic therapy can be started in the same session of the phlebography. In case of success, a dynamic phlebography is performed to confirm the existence of a venous thoracic outlet syndrome. Even if indications for surgical management of primary subclavian vein thrombosis are still controversial, it is actually clear that this multidisciplinary management of these patients has to be as early as possible. Decompression of the thoracic outlet can be performed secondarily using various techniques including first-rib resection. Should this approach fail to re-establish patency, leaving some residual disabling of the arm, axillo-subclavian vein revascularization can provide good mid-term results.

[Severity of aortic ring abscess complicated by cardiac conduction abnormalities]. / Sévérité des endocardites abcédées du manchon aortique compliquées d'anomalies de la conduction.

OBJECTIVE: To determine clinical features, management and prognosis of cardiac conduction abnormalities (CCA) complicating abscessed endocarditis. METHODS: We have analysed clinical, microbiologic and echocardiographic datas, therapies and outcome of cardiac abscesses complicated by CCA in patient hospitalized between 1995 and 2001 in our centre. RESULTS: Above 35 cardiac abscesses, six men (mean age 62 years) had CCA complicating six aortic ring abscesses (4 on native valve and 2 on prosthetic valve) with four cases of interventricular septal involvement and fistulization. Severe heart failure is present four times, a septic cerebral embolization twice. Streptococcus and Staphylococcus prevail. Complete atrioventricular block (AVB) reveals endocarditis twice and complicates the evolution three times. Trifascicular block (first degree AVB, left anterior fascicular block and complete right bundle branch block) revealed recurrence of endocarditis. Two patients were treated medically: one died quickly (complete AVB pre-mortem), and the other one had favourable issue (paroxystic complete AVB). Four patients had surgery with temporary pacemaker in three cases (one died) then definitive pacemaker in two cases. At 26.5 month (7-50), the four survivors had no recurrence of endocarditis. CONCLUSION: Severe CCA are classical in aortic ring abscessed endocarditis and associated with increased mortality. Immediate transfert in a dentre with cardiac surgery is necessary. Definitive cardiac pacing can be performed early without leads infection.

[Outcome of 30 congenital atrio-ventricular blocks]. / Devenir à long terme de 30 blocs auriculo-ventriculaires complets congénitaux isolés.

Congenital isolated atrio-ventricular block (CAVB) is a rare pathology, and its management is still rather poorly described through international literature. Within the service of pediatric cardiology leaded by Pr Choussat and Dr Jimenez (Cardiologic Hospital Haut-Lévêque of Bordeaux), we collected from 1980 to 2003, 30 isolated congenital CAVB, constituting the purpose of this retrospective study. Average follow-up is 14 +/- 8.8 years. None death occurred. CAVB are discovered at an average age of 4.8 years old; 6 cases were diagnosed in utero, half of them were associated with maternal lupus. Twenty patients on 30 were fitted with stimulator at an average age of 8.7 +/- 6.9 years old, due to symptoms or bradycardy. Epicardic fitting in VVI mode represents 65% of first approaches, it is followed by endocavitary way for 81% of cases. Cardiac stimulation does not prevent from dilated cardiomyopathy. Among 30 patients 10 were not fitted with stimulator, half of them presents chronotrop insufficiency during effort. As a conclusion, our patients show a good long-term vital prognosis; although CAVB discovered in utero lead to worse prognosis for children.

Oxygen uptake response to an 800-m running race.

We tested the hypothesis that time course of O (2) uptake (VO (2)) measured during a supramaximal exercise performed in the field is driven to maximal oxygen uptake (VO (2max)). On an outdoor track, five middle-distance male runners first performed a test to determine VO (2max) and a supramaximal 800-m running test at least two days apart. VO (2) response was measured from the start to the end of exercise with the use of a miniaturised telemetric gas exchange system (Cosmed K4). VO (2max) was reached by all subjects 45 +/- 11 s (mean +/- SD) after the onset of the 800-m race (i.e., 316 +/- 75 m), and was maintained during the next 33 +/- 6 s (i.e., 219 +/- 41 m). The mean relative exercise intensity of the 800 m was 120 % VO (2max). An unexpected significant decrease in VO (2) (24.1 +/- 7.0 %; p < 0.05) was observed in all subjects during the final 38 +/- 17 s (i.e., the last 265 +/- 104 m). We concluded that, at onset of a simulated 800 m running event, VO (2) is quickly projected towards the VO (2max), and then becomes limited by the achievable VO (2max). This race profile shown by all athletes is in some contrast to what can be expected from earlier findings in a laboratory setting.

Endofibrosis of the iliac arteries: an underestimated problem.

Arterial endofibrosis is a recently discovered artery disease that is specific to endurance athletes. Cycling is the sport that has shown the greatest number of cases. The endofibrosis is located most frequently in the external iliac artery, but other locations must also be sought. Thigh pain during supramaximal exercise and patient questioning provide strong indications. The diagnosis is confirmed when there is concordance of exercise-induced symptoms, a positive exercise test result and discrete arteriographic characteristics. Treatment is based on folate supplements and standardised surgery carried out by an experienced surgical team.

[A strange case of phlebitis]. / Une phlébite curieuse.

Report of a rare case concerning an elderly man (81 years) suffering from a leiomyosarcoma of the leg already metastasized to the lungs, discovered in connection with a suspected thrombophlebitis. This sarcoma developed from the smooth muscle of a leg vessel, probably a vein. Leiomyosarcoma is a malignant mesenchymal tumor of specialized connective tissue, with a strong potential for local proliferation and metastatic spread. It usually involves the uterine muscle or the wall of the digestive tract, as well as the large vessels of the abdomen and thorax, the prostate very seldom, and only exceptionally a peripheral vein as in this case. The diagnosis suggested by imaging techniques (in particular MRI) is first and foremost immunohistochemical. The treatment is surgical when possible, associated with radiotherapy and chemotherapy as appropriate. The prognosis is especially poor when the diagnosis is made at the metastatic stage.

Surgery for post infarction ventricular septal defect (VSD): risk factors for hospital death and long term results.

OBJECTIVE: Repair of post infarction ventricular septal defect (VSD) is still a challenging procedure with a high risk of recurrence of the VSD and subsequent mortality. The aim of this retrospective study was to assess if technical change in the surgical procedure was followed by an improvement in recurrence of the VSD and operative results. METHOD: This retrospective study from 1971 to 2001 included 85 patients operated on early (<15 days) after the occurrence of a post infarction VSD. Double patch technique was introduced in 1986. A total of 44 variables were studied by a uni- and multivariate analysis. RESULTS: Hospital death occurred in 36 patients. Significant factors for hospital mortality included: preoperative and evolution of the clinical status, right ventricular function and type of repair (one or two patches). Moreover, no recurrence was observed in patients repaired with the double patch technique (P=0.09). None of the studied variables were significant for long term survival. Concomitant CABG was not associated with higher hospital mortality and long-term survival rate was similar in patients with or without concomitant CABG. CONCLUSION: The use of the double patch technique and glue by avoiding recurrence of the VSD played a role in the reduction of the hospital mortality. This technique has to be recommended in the early repair of post infarction VSD. Concomitant CABG can be done safely to control the added risk of an associated coronary artery lesion.

Structure of mouse L-chain ferritin at 1.6 A resolution.

Cubic F432 crystals of recombinant mouse L-chain apoferritin were obtained by the hanging-drop technique with ammonium sulfate and cadmium sulfate as precipitants. The structure was refined to 2.1 and 1.6 A resolution from data obtained at room temperature and under cryogenic conditions, respectively. The structure of an eight-amino-acid loop insertion in the mouse sequence is found to be highly disordered both at room temperature and at low temperature.

Pressure measurements at rest and after heavy exercise to detect moderate arterial lesions in athletes.

PURPOSE: This study defined how ankle arterial blood pressure measurements should be analyzed for the detection of moderate arterial disease (asymptomatic while walking). We used external iliac artery endofibrosis as a unique model of an isolated moderate arterial lesion, the role of which in exercise-related pain can be surgically proven. METHODS: Patients who were ambulatory in our institutional referral center were studied. Brachial pressures, ankle pressures, and heart rate were measured simultaneously on all four limbs at rest and after maximal exercise in 108 healthy athletes and 78 patients (among 89 athletes referred for suspicion of endofibrosis) with confirmed or excluded external iliac endofibrosis. For these 78 patients, we calculated systolic ankle pressure change, ankle/brachial index, and deviation from the ankle/brachial index to heart rate regression line (DAHR) that was defined in the 108 healthy athletes. RESULTS: In patients with endofibrosis, ankle/brachial index and ankle pressure were normal at rest. One minute after exercise, areas (mean +/- SE of area) under the receiver operating characteristics curve for the diagnosis of endofibrosis were 0.91 +/- 0.02, 0.91 +/- 0.03, 0.95 +/- 0.02, and 0.96 +/- 0.02 for ankle pressure, pressure change, ankle/brachial index, and DAHR, respectively. For all criteria, area decreased with time in the recovery period. CONCLUSION: After heavy-load exercise, the ankle/brachial index at minute 1 should be used rather than the systolic ankle pressure value or ankle pressure change as a means of improving the efficacy of the detection of endofibrosis in athletes. A 0.66 value of the index at minute 1 after maximal exercise seems an optimal cutoff point for clinical use, providing a 90% sensitivity rate and 87% specificity rate in the diagnosis of moderate arterial lesions. At rest and after 1 minute of recovery, the ankle/brachial index to heart rate relationship should be considered to be an efficient tool for analyzing the results of pressures measurements and improving detection efficiency.

[Hepatic artery aneurysms]. / Anévrysmes des artères hépatiques.

AIM OF THE STUDY: The aim of this retrospective study was to report a series of nine aneurysms of the hepatic arteries, including real aneurysms (n = 4), pseudoaneurysms (n = 3) and false aneurysms (n = 2) observed from 1987 to 1999. PATIENTS: There were 7 men and 2 women (mean age: 58 years). In 3 cases, the aneurysm was asymptomatic and detected by sonography; in 4 cases it was revealed by rupture with a severe hemorrhage and in 2 cases by cholestasis. The aneurysm was located on right (n = 3), proper and common (n = 3), proper (n = 2), and common (n = 1) hepatic arteries. The aneurysm was associated with hepatocellular carcinoma (n = 1), carcinoma of the head of the pancreas (n = 1) and liver metastases (n = 1). METHODS AND RESULTS: Eight patients were operated and one of them was operated three times. Hepatic arterial blood supply was restored in 6 patients with simple suture (n = 1), Goretex graft (n = 2), allograft (n = 2) and autologous vein (n = 1), with one failure which required liver retransplantation. Only one of the three attempts of embolization was successful. One patient with surgical contraindications died from hemobilia after embolization failure. During follow-up, there was one thrombosis of the common hepatic artery which had been excluded and two late deaths: one from rupture of a false aneurysm after bypass with an allograft and one by terminal progression of the cancer. The other 6 patients were alive at the time of this study. CONCLUSION: Clinical characteristics and therapeutic indications of hepatic arterial aneurysm are variable. Management is usually surgical, while embolization is reserved for special circumstances. Restoration of the hepatic arterial blood supply is necessary in aneurysms located on the proper hepatic artery.

Long-term results of venous revascularization for Paget-Schroetter syndrome in athletes.

The indications for surgical management of primary subclavian vein thrombosis are not agreed upon. This report describes our experience in the treatment of exertional thrombosis causing Paget-Schroetter syndrome in 10 athletes between 18 and 45 years of age. In seven patients urokinase was injected and this resulted in complete revascularization in three cases (42.9%). The remaining three patients were treated by anticoagulation using heparin with adjuvant Coumadin after resolution of thrombosis. Duplex ultrasonography and dynamic phlebography were performed to assess the results of drug treatment. Decompression of the thoracic outlet was performed secondarily using various techniques, including first-rib resection in 10 cases, scalenectomy in 9, and resection of a clavicular callus in 1 case. In six patients, persistent debilitating venous stasis required revascularization by axillojugular bypass in three cases, thrombectomy in two, and axillojugular anastomosis in one case. All patients were reexamined. Mean follow-up was 45 months. Symptomatic relief and vein patency was achieved in all cases. All patients were able to resume sports activity. In agreement with previous studies, our findings confirm the efficacy of immediate anticoagulation, thrombolysis, and complete decompression of the thoracic outlet. Should this approach fail to reestablish patency, axillosubclavian vein revascularization can provide good mid-term results.