Modelling gastrointestinal parasitism infection in a sheep flock over two reproductive seasons: in silico exploration and sensitivity analysis.

In reproducing ewes, a periparturient breakdown of immunity is often observed to result in increased fecal egg excretion, making them the main source of infection for their immunologically naive lambs. In this study, we expanded a simulation model previously developed for growing lambs to explore the impact of the genotype (performance and resistance traits) and host nutrition on the performance and parasitism of both growing lambs and reproducing ewes naturally infected with Teladorsagia circumcincta. Our model accounted for nutrient-demanding phases, such as gestation and lactation, and included a supplementary module to manage the age structure of the ewe flock. The model was validated by comparison with published data. Because model parameters were unknown or poorly estimated, detailed sensitivity analysis of the model was performed for the sheep mortality and the level of infection, following a preliminary screening step. The parameters with the greatest effect on parasite-related outputs were those driving animal growth and milk yield. Our model enables different parasite-control strategies (host nutrition, breeding for resistance and anthelmintic treatments) to be assessed on the long term in a sheep flock. To optimize in silico exploration, the parameters highlighted by the sensitivity analysis should be refined with real data.

[Evaluation of management of infarction in the Franche Comté province by the use of the Franche Comté Cardiology Registry, May 2005-May 2006]. / L'évaluation des pratiques professionnelles pour la prise en charge des infarctus en Franche-Comté. Expérience d'une évaluation à l'échelle régionale par l'utilisation des données du registre franc-comtois de cardiologie, mai 2005-mai 2006.

RATIONALE: The management of acute infarction often necessitates a network of organisation between different centres, thus making it the object of an evaluation of professional practices (EPP). We report the experience in the Franche Comté province of an EPP at a regional level in the management of infarction. METHODS: All of the patients admitted to 10 of the 11 centres in the region were included in a prospective survey. Quality indicators for acute and chronic care were defined, as well as scores, on the basis of use of treatments specified in guidelines. RESULTS: Between May 2005 and May 2006, 1,170 patients were admitted. The patients' risk levels and quality scores were calculated. The rate of use of the quality indicators was higher in our survey than that observed in all of the published studies, except for the use of betablockers. The quality of care could therefore be considered as highly satisfactory. Comparison between the centres revealed some differences. Even after adjustment for the risk score on admission, the quality score for acute care was related to mortality at 1 month. CONCLUSIONS: An EPP is possible for the management of infarction, on a regional scale such as in the province of Franche Comté. The acute quality score turned out to be an independent factor for mortality. The indicators showed that the quality of care was highly satisfactory, even though more progress could be made in the prescription of betablockers.

Effects of early high-dose streptokinase intravenously on left ventricular function in acute myocardial infarction.

One hundred seven patients who recently had acute myocardial infarction were randomly assigned either to standard heparin therapy or to intravenous streptokinase within 5 hours after the onset of symptoms in 7 hospitals without catheterization facilities. In the third week, the patients were referred to a university hospital, where the patency rate of the infarct-related artery was studied by selective coronary arteriography and left ventricular function by radionuclide angiography. Fifty-five patients received heparin and 52 streptokinase within a mean period of 190 minutes after the onset of symptoms. Seven patients in the heparin group and 4 in the streptokinase group died in hospital. The patency rate of the infarct-related artery was identical in both groups (69% in the heparin group vs 68% in the streptokinase group). Left ventricular ejection fraction was not statistically different (0.44 +/- 0.13 in the heparin group vs 0.45 +/- 0.12 in the streptokinase group). Left ventricular ejection fraction was significantly higher in patients with a patent infarct-related artery than in patients with an obstructed infarct-related artery (0.49 +/- 0.12 vs 0.41 +/- 0.15, p less than 0.01). In patients with inferior wall infarction, left ventricular ejection fraction was identical (0.50 +/- 0.10 in the heparin group vs 0.52 +/- 0.09, in the streptokinase group). In patients with anterior wall infarction, left ventricular ejection fraction was significantly higher in the streptokinase group than in heparin group (0.40 +/- 0.10 vs 0.33 +/- 0.09, p less than 0.05). Analysis of regional wall motion revealed that improvement occurred in the lateral wall of the left ventricle.(ABSTRACT TRUNCATED AT 250 WORDS)

Changes in plasma fibrin degradation products as a marker of thrombus evolution in patients with deep vein thrombosis.

The level of fibrin degradation products (fdp) as a marker of fibrin clot dissolution was studied prospectively in 51 patients with phlebographically identified deep vein thrombosis (DVT). For this purpose a highly sensitive fdp assay using an anti D neo monoclonal antibody (McAb) was used. At the onset of the hospitalization, in 47 (92%) of the 51 patients tested, the plasma fdp level performed was high, but does not reflect the size of the thrombus, demonstrating that spontaneous thrombus lysis varies from one patient to another. During 10 days of standard heparin or low molecular weight heparin treatment, two different patterns of fdp evolution could be identified in these patients, independent of the type of heparin used. The first was characterized by a gradual decrease in fdp level and a corresponding reduction in the thrombus size. The second pattern showed a persistence of high levels of fdp after 10 days of therapy although the phlebographic score reveals a poor or partial response indicating that fibrinolysis or the balance of thrombus formation/fibrinolysis did not insure total thrombus dissolution. The 4 patients whose initial plasma fdp levels were only slightly increased during the 10 days, seem to have poor thrombolysis, as was shown by the unmodified phlebographic score after 10 days of treatment. Consequently, we conclude that the investigation of plasma fdp levels with a highly sensitive assay should contribute to the evaluation of thrombus evolution in DVT.

Experimental infection of Columba livia with paramyxovirus Yucaipa.

The town pigeons (Columba livia) were inoculated intranasally with a Yucaipa-like virus (PLOC/Senegal/273/77). They were then surveyed for virus production in the cloaca over a 10 day period. The virus could be isolated at two, three and four days after inoculation.

[Severe thrombopenia from heparin: value of the use of low molecular weight heparin. Apropos of 6 cases]. / Les thrombopénies graves à l'héparine: intérêt de l'utilisation de l'héparine à bas poids moléculaire. A propos de 6 observations.

Severe heparin-induced thrombocytopaenia associated with thromboembolism is a well known complication, although the exact pathogenic mechanism remains unclear. It sets the problem of whether to continue heparin therapy because standard heparin must be withdrawn. Heparin is a mucopolysaccharide composed of fractions of different molecular weights. The fractions with high molecular weights have been held responsible for these severe thrombocytopenias and so, the use of low molecular weight heparin has been suggested. The authors used subcutaneous low molecular weight heparin (CY 216 Choay Institute) at empirical doses of 350 to 1 500 units/kg/24 hour in six cases of severe heparin-induced thrombocytopaenia. Platelet counts rapidly returned to normal (4 days on average) in 5 cases. Thrombocytopaenia persisted with low molecular weight heparin in 1 case. The study of platelet aggregation was positive with low molecular weight heparin in this case and the platelet count returned to normal when the treatment was withdrawn. The authors conclude that, although low molecular weight heparin is useful in severe heparin-induced thrombocytopaenia, its efficacy remains modest. Not only may platelet aggregation persist with low molecular weight heparin which rekindles the debate as to its pathogenic mechanism, but also low molecular weight heparin may have a slight antithrombin effect which limits its use in patients at high risk of thromboembolism, imposing treatment with fast acting vitamin K antagonists.

[Severe thrombopenias during heparin therapy. A phenomenon of intra-vascular platelet aggregation]. / Les thrombopénies majeures au cours d'un traitement héparinique. Phénomène d'agrégation plaquettaire intra-vasculaire.

Haemorrhage or thromboembolism during heparin therapy are usually attributed to a prescribing error. However, these clinical manifestations--especially thromboembolism--may occur with heparin therapy during severe thrombocytopenia. The authors describe the clinical, biological and physiopathological features characterising this thrombocytopenia with reference to 7 personal cases and a review of the literature. The incidence of heparin-induced thrombocytopenia varies between 0.5 and 1%. It seems to be more common (4%) during heparin therapy for thromboembolic disease. The thrombocytopenia appears 8 days after the onset of heparin therapy. It is characterised by the high incidence of thromboembolism (70% of cases) compared to haemorrhagic phenomena (10% of cases). Thrombocytopenia is asymptomatic in 20% of cases. The thrombocytopenia is peripheral, i.e. the bone marrow is normal, and isolated, i.e. there are no deficiencies in the factors of coagulation. One of our cases was of special interest because it was complicated by disseminated intravascular coagulation. Eight cases of disseminated intravascular coagulation have previously been reported. Analysis of platelet aggregation demonstrates the relationship between heparin and thrombocytopenia. Mixing the plasma of patients with thrombocytopenia and plasma rich in platelets in the presence of heparin lead to thrombo-agglutination. In contrast, in control and non-thrombocytopenic heparinised subjects, no reaction was found. These observations prove the existence of a platelet aggregant factor in the plasma during thrombocytopenia. This disappears 6 weeks to 2 months after stopping heparin. This platelet aggregant factor initiates platelet aggregation which is responsible for thrombocytopenia and for the initiation of phenomena of coagulation, so explaining the thromboembolic phenomena.(ABSTRACT TRUNCATED AT 250 WORDS)

[Method of isotopic determination of aortic valve regurgitation]. / Méthode de détermination isotopique des régurgitations valvulaires aortiques.

The index of valvular regurgitation was measured by two techniques after technetium 99 m gamma-cineangiography: the classical technique of comparing left and right ventricular stroke volumes, and the same technique after subtracting the radioactivity arising from the right atrium from the zone of right atrioventricular superposition. The index of valvular regurgitation was calculated in 41 patients with chronic coronary artery disease without valvular regurgitation and also undergoing coronary angiography with 30 degrees right anterior oblique ventriculography, in 8 healthy volunteer subjects, at rest and on exercise; and in 15 patients with chronic aortic regurgitation also undergoing cardiac catheterization and 30 degrees right anterior oblique left ventriculography and aortography. The regurgitant index by the classical technique was 1,25 +/- 0,18; when the index was calculated again after subtracting right atrial radioactivity, a value of 1,05 +/- 0,12 (p less than 0,01) was obtained. The regurgitant index is not affected by left ventricular contractility or by the degree of left ventricular dilatation. On the other hand, this index is affected by the degree of right ventricular dilatation. The valvular regurgitant index did not vary significantly on exercise (1,01 +/- 0,11 to 1,17 +/- 0,16 NS). The isotopic regurgitant fraction deduced from the valvular regurgitant index correlated well with the angiographic regurgitant fraction (R = 0,74; p less than 0,001). The index of valvular regurgitation gives an exact, reliable and reproducible quantification of left sided regurgitant lesions. It is only valid when there is no intracardiac shunt or regurgitant right heart lesion.

[Course of ejection fraction, regurgitation fraction and ventricular volumes during exertion in chronic aortic insufficiency. Study using technetium 99m gamma-cineangiography]. / Evolution au cours de l'effort de la fraction d'éjection, de la fraction de régurgitation et des volumes ventriculaires dans l'insuffisance aortique chronique. Etude par gamma-ciné-angiographie au technetium 99 m.

Previous studies have shown that variations of the ejection fraction (EF) during exercise were representative of the contractile state of the left ventricle: an increased EF on effort is considered to be physiological, whilst a decrease would indicate latent LV dysfunction unmasked during exercise. This hypothesis was tested by performing Technetium 99 gamma cineangiography at equilibrium under basal conditions and at maximal effort in 8 healthy subjects and 44 patients with pure, severe aortic regurgitation to measure the ejection and regurgitant fractions and the variations in end systolic and end diastolic LV volume. In the control group the EF increased and end systolic volume decreased significantly on effort whilst the regurgitant fraction and end diastolic volume were unchanged. In the 44 patients with aortic regurgitation no significant variations in EF, end systolic and end diastolic volumes were observed because the individual values were very dispersed. Variations of the EF and end systolic volume were inversely correlated. The regurgitant fraction decreased significantly on effort. Based on the variations of the EF and end systolic volume three different types of response to effort could be identified: in 7 patients, the EF increased on effort and end systolic volume decreased without any significant variation in the end diastolic volume, as in the group of normal control subjects; in 22 patients, a reduction in EF was observed on effort, associated with an increased end systolic volume. These changes indicated latent IV dysfunction inapparent at rest and unmasked by exercise; in a third group of 15 patients, the EF decreased on effort despite a physiological decrease in end systolic volume due to a greater decrease in end diastolic volume.(ABSTRACT TRUNCATED AT 250 WORDS)

[Intravenous streptokinase versus heparin in recent acute myocardial infarction. Randomized multicenter study in the Franche-Comté]. / Streptokinase intraveineuse versus héparine dans l'infarctus du myocarde aigu récent. Etude randomisée multicentrique franc-comtoise.

A multicentre randomised therapeutic trial was undertaken in 8 hospitals in the Franche-Comté department of France (Belfort, Besançon, Dole, Lons-le-Saunier, Luxeuil, Montbéliard, Vesoul, Pontarlier) in which 101 patients with acute primary myocardial infarction were treated within 5 hours of onset of symptoms with either intravenous streptokinase (1,500,000 U in 30 mn) or conventional heparin therapy. The results were assessed on the clinical outcome, arterial patency in the necrosed territory and global and regional ejection fractions (EF) at the 3rd week. After randomisation, 51 patients were given heparin and 50 received streptokinase. Seven patients died in the heparin group and 4 in the streptokinase group (NS). At the third week, the artery in the necrosed zone was patent in 69% of the heparin group and in 68% of the streptokinase group (NS). The EF was significantly higher in the patients with patent arteries in the necrosed zone than in those with occluded arteries (0.49 +/- 0.12 vs 0.41 +/- 0.15, p less than 0.01). There was no significant difference in EF between the heparin and streptokinase groups. The EF was significantly higher in patients with anterior infarction who received streptokinase than in those who received heparin (0.40 +/- 0.10 vs 0.33 +/- 0.09 p less than 0.05). Segmental wall motion was significantly better at the apex and free wall. There was no significant difference between the two groups in posterior infarction. These results show that reestablishment or maintenance of arterial patency in the necrosed zone improves left ventricular function and that patients with anterior wall infarction are the ones most likely to benefit from streptokinase therapy.

[Anomalies in left ventricular systolic function disclosed by exercise testing in chronic aortic insufficiency. Study by cavitary scintigraphy]. / Les anomalies de fonction systolique ventriculaire gauche dévoilées par l'effort dans l'insuffisance aortique chronique. Etude par scintigraphie cavitaire.

Fifty-two patients with a symptomatic chronic aortic insufficiency underwent radionuclide angiography. The following parameters were measured at rest and at peak exercise: ejection fraction, regurgitant fraction, ventricular volumes, stroke volume, cardiac output and an index of systemic arterial resistance. The ventricular dimensions, the thickness of the septal and posterior walls, left ventricular myocardial mass and endsystolic stress were determined by 2D echocardiography. The patients were divided into 3 groups based on left ventricular changes on exercise: the first group (18 patients) had physiological left ventricular adaptation to exercise (increased ejection fraction, reduced endsystolic volume); a second group of 18 patients had moderate left ventricular dysfunction (absence of increase in ejection fraction and a reduction of less than 20% of endsystolic volume with respect to basal values); a third group of 17 patients had what was considered to be severe left ventricular dysfunction (decreased ejection fraction of over 5% and increased endsystolic volume of over 20% with respect to basal values). There was no significant difference between the three groups with respect to basal values of ejection fraction, ventricular volumes and systemic arterial resistance. On exercise, the heart rate, blood pressure and systemic arterial resistances varied in a comparable manner in each of the three groups. The left ventricular dimensions and myocardial mass were identical in the three groups. Only left ventricular endsystolic strain tended to be higher in the third group of patients compared with the other two, but the difference was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

[Determination of ventricular volumes by a non-geometric method using gamma-cineangiography]. / Détermination des volumes ventriculaires par une méthode non géométrique utilisant la gamma-cinéangiographie.

The authors suggest a new way of determining ventricular volume by a non-geometric method using gamma-cineangiography. The results obtained by this method were compared with those obtained by a geometric methods and contrast ventriculography in 94 patients. The new non-geometric method supposes that the radioactive tracer is evenly distributed in the cardiovascular system so that blood radioactivity levels can be measured. The ventricular volume is then equal to the ratio of radioactivity in the LV zone to that of 1 ml of blood. Comparison of the radionuclide and angiographic data in the first 60 patients showed systematic values--despite a satisfactory statistical correlation (r = 0.87, y = 0.30 X + 6.3). This underestimation is due to the phenomenon of attenuation related to the depth of the heart in the thoracic cage and to autoabsorption at source, the degree of which depends on the ventricular volume. An empirical method of calculation allows correction for these factors by taking into account absorption in the tissues by relating to body surface area and autoabsorption at source by correcting for the surface of isotopic ventricular projection expressed in pixels. Using the data of this empirical method, the correction formula for radionuclide ventricular volume is obtained by a multiple linear regression: corrected radionuclide volume = K X measured radionuclide volume (Formula: see text). This formula was applied in the following 34 patients. The correlation between the uncorrected and corrected radionuclide volumes and the angiographic volumes was improved (r = 0.65 vs r = 0.94) and the values were more accurate (y = 0.18 X + 26 vs y = 0.96 X + 1.5).(ABSTRACT TRUNCATED AT 250 WORDS)

[Exertion-induced parameters of left ventricular function in patients with chronic cardiac insufficiency. An isotope study]. / Evolution à l'effort des paramètres de fonction ventriculaire gauche chez des patients atteints d'une insuffisance cardiaque chronique. Etude isotopique.

Exercise-induced changes in haemodynamic values were studied by radionuclide ventriculography in 21 patients with permanent systolic dysfunction (15 with non-obstructive cardiomyopathy and 6 with ischaemic heart disease). The results were compared with those obtained in 8 control subjects with normal heart. In healthy subjects, during exercise the ejection fraction increased due to constant diminution of the end-systolic volume; the end-diastolic volume and the systolic ejection volume did not significantly vary; the cardiac output augmented only because of the accelerated heart rate. In patients with permanent left ventricular dysfunction, the ejection fraction remained unchanged during exercise, whereas the end-systolic volume increased significantly. Yet the systolic ejection volume increased due to a rise in end-diastolic volume. Heart rate and cardiac index increased, but not as much as in normal subjects. There was a close correlation between changes in end-diastolic and end-systolic volumes. It was the relative importance of changes in these two ventricular volumes that determined the direction and amplitude of variations in ejection fraction. It is concluded that in patients with permanent left ventricular dysfunction: (1) the end-systolic volume increases during exercise, thus betraying a worsening of the systolic dysfunction; (2) however, the systolic ejection volume is maintained or increases due to an increase in end-diastolic volume; (3) the changes in ejection fraction observed during exercise are of little value to characterize the modifications that occur in left ventricular work performance.

[Efficacy of a very low molecular weight heparin fragment (CY 222) compared to standard heparin in patients with deep venous thrombosis. A randomized study]. / Efficacité d'un fragment d'héparine de trés faible poids moléculaire (CY 222) comparée à l'héparine standard chez des patients porteurs d'une thrombose veineuse profonde. Etude randomisée.

Low molecular weight heparin fractions have been demonstrated as efficient as low doses of standard heparin in preventing post-operative deep-vein thrombosis. Several clinical studies are, now, carrying out in patients with acute deep-vein thrombosis in order to assess efficacy and safety of low molecular weight heparin fractions as compared to standard heparin. In a randomised study including patients with deep-vein thrombosis treated either with low molecular weight heparin or with subcutaneously standard heparin, we demonstrated an effectiveness, in terms of thrombus reduction, of low molecular weight heparin as well as standard heparin. However, low molecular weight heparin seemed to be safer than standard heparin.

[Comparative anti-ischemic activity of atenolol and diltiazem. Crossed single-blind randomized study using a computerized exercise test]. / Activité anti-ischémique comparée de l'aténolol et du diltiazem. Etude randomisée simple aveugle croisée par épreuve d'effort informatisée.

The anti-ischaemic activities of atenolol (200 mg) and diltiazem (240 mg) were compared in 23 patients undergoing retraining 4 weeks after a limited postero-inferior or anterior primary myocardial infarction. The patients, who had signs of residual ischaemia during stress with or without angina, were subjected to 3 exercise tests on a bicycle ergometer; a computer was used to analyze the results (Case-Marquette). The first test was performed under placebo, the second after randomized treatment with one of the two drugs and the third test after taking the other drug. The parameters evaluated were: total duration of the test, time of occurrence of a 1 mm ST-segment depression, maximal work load and total work performed, heart rate, systolic arterial pressure, heart rate X systolic arterial pressure product at rest and at submaximal and maximal stress, and ST depression at submaximal and maximal stress. The results showed that exertion was improved to the same degree by the two drugs, but atenolol had greater anti-ischaemic activity than diltiazem.

[A new treatment of deep venous thrombosis: low molecular weight heparin fractions. Randomized study]. / Un nouveau traitement des thromboses veineuses profondes: les fractions d'héparine de bas poids moléculaire. Etude randomisée.

Sixty-eight patients with acute deep vein thrombosis were allocated at random to two treatment groups. One group (n = 33) received a fixed dose of 750 anti-Xa units of a low molecular weight heparin (CY 222 Choay Institute); the other group (n = 35) received standard heparin in doses of 500 IU/kg/24 h. Both treatments were given for 10 days in two daily subcutaneous injections. A second phlebography was performed on the last day of treatment. No haemorrhagic complication was observed in the group treated with CY 222, as opposed to three cases of haemorrhage in the group treated with standard heparin. The initial phlebographic score and the location of deep vein thrombotic lesions were the same in both groups. Angiographic improvement, with more than 30% thrombolysis, was obtained at the end of treatment in 64% of patients in the CY 222 group and in 65% of patients in the standard heparin group (NS). In 2 patients treated with standard heparin the second phlebography showed extension of the thrombosis. The initial score remained unchanged in 1/3 of patients in both groups. The activated partial thromboplastin time was prolonged (2 or 3 fold the normal value) in the standard heparin group and unchanged in the CY 222 group. Anti-Xa activity was significantly higher in the CY 222 group than in the standard heparin group. It is concluded that CY 222 and standard heparin were equally effective in patients with deep vein thrombosis. However, haemorrhagic complications were more frequent with standard heparin that with CY 222.

[Anatomical and coronary angiography data on coronary anastomosis]. / Anastomoses coronariennes données anatomiques et coronarographiques.

Beyond two series of heart studies (anatomical with 150 hearts treated by injection-corosion method, and angiographic with 211 coronarography 3 days after a heart attack) the authors have noticed 92 coronary anastomosis with: 28 right homolateral 22 left homolateral 42 contralateral The existence of these anastomosis has been confirmed by coronarography of 30 out of 173 patients having a significant lesion of the artery responsible for the heart attack. The authors noticed also that these anastomosis are effective when the coronary system is deficient and the supplies are ensured by the other artery. The study permits to distinguish two groups of functional collateral: the functional collateral spontaneously observed during coronarography recruitable collaterals which are ready to be functional in case of main coronary artery obstruction.