Characterization and potential applications of progenitor-like cells isolated from horse amniotic membrane.

The aim of this work was to isolate, for the first time, progenitor-like cells from the epithelial (AECs) and mesenchymal (AMCs) portions of the horse amniotic membrane, and to define the biological properties of these cells. AECs displayed polygonal epithelial morphology, while AMCs were fibroblast-like. Usually, six to eight passages were reached before proliferation decreased, with 13.08 and 26.5 cell population doublings attained after 31 days for AECs and AMCs, respectively. Immunocytochemical studies performed at passage 3 (P3) showed that both cell populations were positive for the expression of specific embryonic markers (TRA-1-60, SSEA-3, SSEA-4 and Oct-4). Meanwhile, RT-PCR performed at P1 and P5 showed expression of mesenchymal stem/stromal cell markers (CD29, CD105, CD44 and CD166) with negativity for CD34 at P1, although this marker began to be expressed by P5. The cells also expressed MHC-I at both P1 and P5, but lacked MHC-II expression at P1. Both AECs and AMCs demonstrated high plasticity, differentiating in vitro toward the osteogenic, adipogenic, chondrogenic and neurogenic lineages. Equine amnion-\derived cells could also be frozen and recovered without loss of their functional integrity in terms of morphology, presence of specific stemness markers and differentiation ability, although the renewal capacity was lower than that observed for freshly isolated cells. To investigate potential therapeutic effects and cell tolerance in vivo, horse amnion-derived cells were allogeneically injected into three horses with tendon injuries, resulting in a quick reduction in tendon size and ultrasonographic cross-sectional area measurements. These results suggest that horse amnion-derived cells may be useful for cell therapy applications.

[Stress cardiomyopathy: report of 2 cases]. / Cardiomyopathie de stress: à propos de deux cas.

The authors reported two cases of acute catecholamines cardiomyopathy expressed clinically by chest pain and dyspnea, without any previous cardiac history. The diagnosis of human stress cardiomyopathy is established on: typically rapid onset aftermath of intense emotional stress, left ventricular apical akinesis and hyperkinetic motion of basal walls imaged by two-dimensional echocardiography. Rapid reversal clinical course and normal coronary arteriography. Similar finding have been observed in conjunction with pheochromocytoma who have been excluded by normal levels of urinary catecholamines metabolites.

[Extensive mycotic coronary aneurysm detected by echocardiography. Apropos of a case]. / Volumineux anévrisme mycotique coronaire de découverte échographique. A propos d'un cas.

The authors report the case of a large mycotic right coronary aneurysm detected at echocardiography in a 45 year old patient with AIDS. Although emergency surgery was planned, the patient died of rupture of the aneurysm with cardiogenic shock and sudden pericardial tamponade. This case underlines the diagnostic value of echocardiography, by the transthoracic approach for para-cardiac masses and with the transoesophageal probe for accurate localisation and demonstration of the coronary origin. In this case, the CT scan was less useful than transthoracic echocardiography. Coronary angiography confirmed the strongly suggestive echocardiographic diagnosis and helped decide management strategy. Atheromatous coronary aneurysms may be treated by stenting but mycotic aneurysms require surgical management.

[Postpartum myocardial infarction induced by Parlodel]. / Infarctus du myocarde du postpartum induit par le Parlodel.

The authors report the case of a 28 year old woman who developed antero-septoapical myocardial infarction in the post-partum period. This was detected by surface ECG and echocardiography performed after a systemic embolism. The infarction followed treatment with Parlodel for inhibition of lactation. Coronary angiography, performed one month post-partum, was normal and the methergin test was negative. The physiopathological mechanism of myocardial infarction resulted from the association of an iatrogenic spastic phenomenon favourised by the patient restarting to smoke and the physiological arterial hyperactivity of the post-partum period. This mechanism raises the question of preventive measures in cases of inhibition of lactation in the post-partum period, notably stopping smoking.

[Peripheral embolic arterial accident due to pulmonary vein thrombosis revealing bronchial carcinoma]. / Accident artériel périphérique embolique par thrombose d'une veine pulmonaire révélant un carcinome bronchique.

The authors report a case of left superior pulmonary vein thrombosis discovered on transoesophageal ultrasonography in the context of aetiological assessment of a systemic vascular accident. This unusual site of a thrombus on an anatomically perfectly normal left atrium led the authors to perform a more detailed assessment, revealing a previously undiagnosed lung cancer on thoracic CT scan.

[Incidental discovery of asymptomatic Loeffler fibroplastic endocarditis. Report of a case]. / Découverte fortuite d'une endocardite fibroplastique de loeffler asymptomatique. A propos d'un cas.

The authors report a case of fibroplastic endocarditis discovered during echocardiography in an asymptomatic patient in the context of assessment of systematized electrocardiographic modifications. The diagnosis, strongly suspected on the basis of the cardiac MRI findings, was finally confirmed by endocardial biopsy.

[Transthoracic echocardiography and diagnosis of acute pulmonary embolism. Change in the diagnostic valve with respect to thresholds of classification]. / Echocardiographie transthoracique et diagnostic d'embolie pulmonaire aiguë. Variation de la valeur diagnostique en fonction des seuils de classification.

The diagnostic value of transthoracic echocardiography in acute pulmonary embolism is not well established. Although many parameters are abnormal, the thresholds used vary according to the authors, limiting the contribution of the investigation to the diagnosis. In a prospective study of 70 patients with suspected acute pulmonary embolism without previous cardio-respiratory disease, the authors tried to determine the diagnostic thresholds using discriminating linear analysis and ROC curves. Parameters easily recorded in an emergency were analysed: end diastolic ventricular dimensions, ratio of these diameters and maximal velocity of tricuspid regurgitant flow. Thirty-one patients had pulmonary embolism quantified by the Miller index (average: 16 +/- 7, range 2 to 28). Measurements of left ventricular dimension were disappointing (sensitivity: 0.52, specificity: 0.73 for a threshold value of 45 mm). The right ventricular dimension was a better predictive parameter (sensitivity: 0.70, specificity: 0.86 for a threshold value of 25 mm). However, the ratio of right to left ventricular dimension had a better diagnostic value (sensitivity: 0.85, specificity: 0.78 for a threshold value of 0.5). The best diagnostic parameter was the maximal velocity of tricuspid regurgitation (sensitivity: 0.93, specificity: 0.82 for a threshold value of 2.5 m/s). The authors conclude that the maximal velocity of tricuspid regurgitation with a threshold of 2.5 m/s and the ratio of the ventricular dimensions with a threshold value of 0.5 are valuable diagnostic indicators for acute pulmonary embolism.

[Estimation of left ventricular volumes and ejection fraction with acoustic quantification in myocardial infarction. Comparison with echocardiographic, angiographic and scintigraphic data]. / Estimation des volumes et de la fraction d'éjection ventriculaires gauches par quantification acoustique dans l'infarctus du myocarde. Comparaison aux données échographiques, angiographiques et scintigraphiques.

The object of this study was to assess the reliability of measurements of left ventricular volumes and ejection fraction by acoustic quantification by the method of summation of discs in acute myocardial infarction. Thirty-two patients with an average age of 55.9 +/- 12 years were studied prospectively on average 6 +/- 2 days after the onset of myocardial infarction. Within 48 hours, the patients underwent TM echocardiography (Teichholz's method) two-dimensional echocardiography (Simpson's method on freeze frames and acoustic quantification) before left ventricular angiography and isotopic ventriculography, considered as the reference methods for comparing left ventricular volumes and ejection fractions. The data displayed in real time by acoustic quantification correlated well with the results of left ventricular angiography (r = 0.77; p = 0.0001) and moderately underestimated (+4.1 +/- 11.9%) the ejection fraction, but were relatively disappointing for estimating volumes. When compared with isotopic ejection fraction, the correlation coefficient was r = 0.71 (p = 0.0004) and the values were overestimated. In this study, acoustic quantification was the most reliable echocardiographic method of assessing the left ventricular ejection fraction with reference to contrast angiography (Teichholz: r = 0.56; p = 0.0014; Simpson: r = 0.76; p = 0.001). The authors conclude that assessing the left ventricular ejection fraction with acoustic quantification is reliable in acute myocardial infarction. However, the method is not very accurate in measuring end systolic and end diastolic volumes.

[Value of transesophageal echocardiography in post-infarction septal ruptures]. / Intérêt de l'échographie transoesophagienne dans les ruptures septales postinfarctus.

The role of transoesophageal echocardiography in the diagnosis of ventricular septal defect in the acute stage of myocardial infarction, was evaluated in 15 consecutive patients (10 men and 5 women) with a mean age of 72 years in the period between June 1991 and April 1995. The patients had 11 anterior infarcts and 4 inferior infarcts with extension to the right ventricle. One patient was in Killips class I,7 patients in class II, 2 in class III and 5 in class IV. Only 8 of the 15 septal ruptures could be visualised directly by conventional transthoracic echocardiography, though all 15 were suspected from continuous Doppler and colour Doppler analysis. Transoesophageal echocardiography was successfully performed in 14 of the 15 patients with a monoplane probe in 11 cases and a multiplane probe in 3 cases. The average duration of the procedure was 12 minutes and clinical and haemodynamic tolerance was good. Ventricular septal defect was directly visualised in all cases in the short axis transgastric view and in 7 cases in transoesophageal views. Transoesophageal echocardiography was concordant with peroperative findings with regards to the site of ventricular septal defect (8 apical, 5 postero-basal and 1 median), their type (6 punched-out defects, 5 fissures, and 3 perforated aneurysms), their size (average 9.3 mm), their number with 5 multiple defects, and associated lesions (4 right ventricular extensions, 4 hemopericardiums and 1 free wall fissure). Transoesophageal echocardiography completes traditional transthoracic echocardiographic examination in the diagnosis of post-infarction ventricular septal defect. It is well tolerated and, in the authors' experience, allows limitation of invasive procedures to coronary angiography alone.

Proposal for the measurement of backward and total scattering by mineral particles suspended in water.

An experimental procedure for the determination of the specific backscattering and total scattering coefficients of mineral particles suspended in water is described. The procedure combines measurements performed on samples of particles retained in glass-fiber filters and suspended in water, using a dual-beam spectrophotometer provided with an integrating-sphere attachment.

Local algorithms using SeaWiFS data for the retrieval of phytoplankton, pigments, suspended sediment, and yellow substance in coastal waters.

Algorithms that use the SeaWiFS radiometer band reflectance data for the retrieval of phytoplankton pigment concentration, suspended sediment concentration, and yellow substance absorption in coastal water are set up by a computation based on a three-component model of sea color. The varying coastal environment is characterized by a site-specific correlation among the three parameters, subjected to large spatial and temporal fluctuations. The computation is performed with respect to the summer situation of the Gulf of Naples (Mediterranean Sea). The sensitivity of the retrieval of each parameter to variations in the concentration of the two other quantities is investigated by numerical simulations. The sensitivity to the variability of the absorption and scattering properties of phytoplankton and suspended sediment is analyzed, as well as the error induced by the uncertainty of the remote-sensing data. The algorithms's performance is satisfactorily tested on sets of SeaWiFS band reflectances randomly generated within wide water composition ranges. Although the results obtained cannot be generalized and require experimental validation, the series of tests performed suggests that the proposed algorithms, with numerical constants adjusted to the local conditions, can be effectively applied to several types of coastal environment.