Dispersion and transport of energetic particles due to the interaction of intense laser pulses with overdense plasmas.

We study the angular distribution of relativistic electrons generated through laser-plasma interaction with pulse intensity varying from 10(18) W/cm2 up to 10(21) W/cm2 and plasma density ranging from 10 times up to 160 times critical density with the help of 2D and 3D particle-in-cell simulations. This study gives clear evidence that the divergence of the beam is an intrinsic property of the interaction of a laser pulse with a sharp density gradient. It is entirely due to the excitation of large static magnetic fields in the layer of interaction. The energy deposited in this layer increases drastically the temperature of the plasma independently of the initial temperature. This makes the plasma locally collisionless and the simulation relevant for the current experiments.

Genetic diversity within and between European pig breeds using microsatellite markers.

An important prerequisite for a conservation programme is a comprehensive description of genetic diversity. The aim of this study was to use anonymous genetic markers to assess the between- and the within-population components of genetic diversity for European pig breeds at the scale of the whole continent using microsatellites. Fifty-eight European pig breeds and lines were analysed including local breeds, national varieties of international breeds and commercial lines. A sample of the Chinese Meishan breed was also included. Eleven additional breeds from a previous project were added for some analyses. Approximately 50 individuals per breed were genotyped for a maximum of 50 microsatellite loci. Substantial within-breed variability was observed, with the average expected heterozygosity and observed number of alleles per locus being 0.56 [range 0.43-0.68] and 4.5 respectively. Genotypic frequencies departed from Hardy-Weinberg expectations (P < 0.01) in 15 European populations, with an excess of homozygotes in 12 of them. The European breeds were on average genetically very distinct, with a Wright F(ST) index value of 0.21. The Neighbour-Joining tree drawn from the Reynolds distances among the breeds showed that the national varieties of major breeds and the commercial lines were mostly clustered around their breeds of reference (Duroc, Hampshire, Landrace, Large White and Piétrain). In contrast, local breeds, with the exception of the Iberian breeds, exhibited a star-like topology. The results are discussed in the light of various forces, which may have driven the recent evolution of European pig breeds. This study has consequences for the interpretation of biodiversity results and will be of importance for future conservation programmes.

Genetic diversity in European pigs utilizing amplified fragment length polymorphism markers.

The use of DNA markers to evaluate genetic diversity is an important component of the management of animal genetic resources. The Food and Agriculture Organisation of the United Nations (FAO) has published a list of recommended microsatellite markers for such studies; however, other markers are potential alternatives. This paper describes results obtained with a set of amplified fragment length polymorphism (AFLP) markers as part of a genetic diversity study of European pig breeds that also utilized microsatellite markers. Data from 148 AFLP markers genotyped across samples from 58 European and one Chinese breed were analysed. The results were compared with previous analyses of data from 50 microsatellite markers genotyped on the same animals. The AFLP markers had an average within-breed heterozygosity of 0.124 but there was wide variation, with individual markers being monomorphic in 3-98% of the populations. The biallelic and dominant nature of AFLP markers creates a challenge for their use in genetic diversity studies as each individual marker contains limited information and AFLPs only provide indirect estimates of the allelic frequencies that are needed to estimate genetic distances. Nonetheless, AFLP marker-based characterization of genetic distances was consistent with expectations based on breed and regional distributions and produced a similar pattern to that obtained with microsatellites. Thus, data from AFLP markers can be combined with microsatellite data for measuring genetic diversity.

[Treatment of malignant intestinal obstruction. A prospective study over 80 cases]. / Traitement de l'occlusion intestinale sur carcinose péritonéale. Etude prospective à propos de 80 cas.

AIM: Of the work: evaluation of a multidisciplinary strategy and a prospective medicosurgical protocol for the treatment of occlusion due to unresectable peritoneal carcinomatosis. PATIENTS AND METHODS: All the included patients had occlusion and intraabdominal carcinomatosis. None could benefit a curative treatment. 75 patients were included for 80 episodes of intestinal obstruction. The protocol involved three successive therapeutic phases. (i) Treatment during five days by corticosteroids associated to antiemetic agents, anticholinergic antisecretory agents, and analgesics as needed (Phase I); (ii) In the event of refractory occlusive symptoms treatment by somatostatin analog during 3 days (phase II); (iii) If this treatment was ineffective a gastrostomy was performed (phase III). RESULTS: Median survival was 31 days. Outcome showed that for the 80 episodes of obstruction, phase I medical treatment enabled relief in 50 cases (63%) and phase II medical treatment (somatostatin) enabled relief in 11 cases (14%). 10 more patients (13%) were relieved by the gastrostomie and one by a duodenal endoprothesis. Symptom control without a long-term nasogastric tube was achieved for 72 of the 80 episodes (90%). Fifty-eight episodes (72% of overall total) were controlled for 10 days or less. Median time to gastrostomy was 17 days. Eight patients experienced persistent vomiting and required a nasogastric aspiration until death. CONCLUSION: This multidisciplinary approach between Palliative Care and Specialized Medical and Surgical teams enabled relief of the occlusive symptoms for 90% of the patients of the study. The protocol was useful for the caregivers for the management of terminally ill patients. To enhance these results, it would be necessary to shorten the delay of relief, which has been longer than ten days for one third of the patients. The simplification of the protocol including two steps instead of three is on study.

Contagious bovine pleuropneumonia vaccines, historic highlights, present situation and hopes.

Contagious bovine pleuropneumonia (CBPP) is a contagious infection of cattle caused by a mycoplasma, M. mycoides subsp. mycoides SC (MmmSC). It induces lesions of pleuropneumonia in acute cases and the formation of pulmonary "sequestra" in chronic cases. The disease is prevalent mostly in Africa, where it is responsible for high losses, but it has also been sporadically present in Southern Europe until 1999. Vaccination is now prohibited in most countries except in Africa. An empirical "inoculation" procedure was developed as early as 1852 in Europe but it may have been used even earlier in Africa. The inoculation of pleural fluid was performed at the tip of the tail in Europe and on the bridge of the nose in Africa. It conferred good protection but induced a high number of fatal cases. Various inactivated preparations have been tested in the past with inconclusive results leading sometime to some protection and some other time to a sensitisation of the immunised animals. Such preparations have never been used in the field. Attenuated MmmSC strains have been developed in the 1950s and used extensively in the field both in Africa and Australia. The best known vaccine strains are KH3J, T1/44 and T1sr. Vaccination campaigns have succeeded in reducing considerably the CBPP prevalence in these two continents but eradication was achieved in Australia only by switching to strict measures of animal movement control and a stamping-out policy. The search for new CBPP vaccines has become a major issue for African countries that are facing an increase in outbreaks. The rationale for this search is based on a better understanding of the mycoplasma virulence mechanisms that could lead to a targeted attenuation of MmmSC strains. It is also based on a better understanding of the bovine immune response that may be driven to a pathogenic inflammatory response or conversely to a better balanced response leading to protection.

[Patients hospitalized in advanced or terminal phase of a serious life-threatening disease]. / Patients hospitalisés en phase avancée ou terminale d'une maladie grave engageant le pronostic vital. Enquête de prévalence un jpour donné, au Centre hospitalier de Grenpble.

OBJECTIVE: The end-point of this survey was to evaluate the number of patients in advanced or terminal phase of a life-threatening disease and hospitalised in the university hospital in Grenoble on a given day. The secondary end-points were determination of the profile of patients undergoing palliative care and the therapeutic charge they represented for the hospital in order to develop optimal medico-psycho-social responses adapted to the needs of this population, their family and friends and the teams of health professionals who treat them. METHODS: The survey was based on a questionnaire including 106 items and one open question, filled-in by a physician and the nurses of the hospital, together with the interviewer. RESULTS: Out of the 1495 patients hospitalised in the hospital centre (84% occupation), 114 patients were included in the study, i.e., 8% of the total number of patients present. Patients' mean age was of 70 (21

[New Level III opioids of the World Health Organization]. / Nouveaux antalgiques de niveau III de l'Organisation mondiale de la santé.

PURPOSE: The new opioids and the new galenic forms, now available in France, require an update in practitioners' knowledge. The purpose of the present study is to help those prescribing select the appropriate opioid and its galenic form for pain relief. CURRENT KNOWLEDGE AND KEY POINTS: Presentation of pharmacological properties of opioids (mechanisms, pharmacokinetics and pharmacovigilance). Presentation of indications, modes of prescription and use of main opioids for pain (especially cancer pain). Examples for calculating required drug dosage depending on the clinical situation and the route of administration. Symptomatic treatments of the main undesirable side effects of the opioids, and actions to be taken in the event of accidental overdose. FUTURE PROSPECTS AND PROJECTS: Oral morphine is the treatment first recommended for nociceptive pain insufficiently relieved by WHO level I and II analgesics. The new immediate-release galenic forms allow morphine titration and the treatment of breakthrough pain. Transmucosal fentanyl, soon available in France, is recommended for breakthrough pain in patients already under opioid treatment: it gives more rapid relied starting after only 5 minutes and it only acts for a short time. Transdermal fentanyl is indicated for stable cancer pain. It is particularly suitable when oral and injectable morphine routes are not available, or for patients with severe constipation. Hydromorphone is the first opioid recommended in France for severe cancer pain when morphine resistance exists or uncontrolled side effects are present (opioid rotation). The new opioids and the new galenic forms widen the range of therapeutic possibilities. Their use is well codified for cancer pain and must still undergo clinical trials for chronic non-cancer pain. When correctly indicated, opioid selection provides a considerable advance in pain management.

First observation of ion acoustic waves produced by the langmuir decay instability

Thomson scattering measurements are presented which demonstrate conclusively the occurrence of the Langmuir decay instability (LDI) in a laser-produced plasma experiment. Both products of the instability, the ion acoustic wave and the electron plasma wave, were simultaneously observed and identified with their spectral characteristics. The secondary decay of the LDI-generated electron plasma wave, into another Langmuir wave and an ion acoustic wave, has been observed for the first time. The connection with growth and saturation of the stimulated Raman instability is discussed.

Opacity of an underdense plasma slab due to the parametric instabilities of an ultraintense laser pulse

The interaction of ultraintense laser beams with underdense plasma slabs has been investigated with two-dimensional particle-in-cell numerical simulations, showing a strong absorption and a correlatively low transmission. Energetic electrons in the multi-MeV range are produced. At very high intensities the plasma transparency is recovered. These results are interpreted in terms of the development of electron parametric instabilities in the self-consistently heated plasma.

The use of steroids in the management of inoperable intestinal obstruction in terminal cancer patients: do they remove the obstruction?

This multicentre, randomized double-blind study was undertaken to assess the efficacy of corticosteroids as a palliative treatment of intestinal obstruction due to advanced and incurable cancer. Thirty-one French palliative care units agreed to participate in the study and 12 actually recruited at least one patient. To be included, patients had to have an advanced cancer with a surgically inoperable bowel obstruction and to have received no specific anticancer therapy within the preceding 28 days. They had to fulfil at least three of the following criteria: vomiting at least twice a day; colicky abdominal pain; no flatus for 12 h or more; no stool for at least 4 days, faecal impaction being excluded; intestinal distension; air-fluid levels or absence of gas in the colon on an abdominal radiograph. Patients were randomized in three groups to receive either a placebo for 3 days (group A), or methylprednisolone 240 mg daily for 3 days (group B) or methylprednisolone 40 mg daily for 3 days (group C). Symptoms were assessed daily but success or failure of the treatment was assessed on day 4, according to the disappearance or persistence of symptoms. Fifty-eight patients were randomized, of whom 52 were able to be evaluated. Details of symptoms and associated treatments are described below. Of 40 patients without a nasogastric tube, symptoms were relieved in 68% of cases versus 33% among placebo-treated patients (P = 0.047). In 12 patients who had a nasogastric tube already in place, the results are less significant (60% versus 33% with P = 0.080). Because of the small sample size, no conclusions can be reached about the relative efficacy of low versus high-dose treatment regimes.

Genetic diversity of eleven European pig breeds.

A set of eleven pig breeds originating from six European countries, and including a small sample of wild pigs, was chosen for this study of genetic diversity. Diversity was evaluated on the basis of 18 microsatellite markers typed over a total of 483 DNA samples collected. Average breed heterozygosity varied from 0.35 to 0.60. Genotypic frequencies generally agreed with Hardy-Weinberg expectations, apart from the German Landrace and Schwäbisch-Hällisches breeds, which showed significantly reduced heterozygosity. Breed differentiation was significant as shown by the high among-breed fixation index (overall F(ST)= 0.27), and confirmed by the clustering based on the genetic distances between individuals, which grouped essentially all individuals in 11 clusters corresponding to the 11 breeds. The genetic distances between breeds were first used to construct phylogenetic trees. The trees indicated that a genetic drift model might explain the divergence of the two German breeds, but no reliable phylogeny could be inferred among the remaining breeds. The same distances were also used to measure the global diversity of the set of breeds considered, and to evaluate the marginal loss of diversity attached to each breed. In that respect, the French Basque breed appeared to be the most "unique" in the set considered. This study, which remains to be extended to a larger set of European breeds, indicates that using genetic distances between breeds of farm animals in a classical taxonomic approach may not give clear resolution, but points to their usefulness in a prospective evaluation of diversity.

[Angioplasty or surgery in the patient with multivessel disease]. / Angioplastie ou chirurgie chez le patient pluritronculaire.

The aims of myocardial revascularisation are to treat angina, reduce ischaemia and improve life expectancy. Patients with multivessel disease have a poor prognosis, especially when the lesions are proximal, when the preseptal left anterior descending artery is involved and when left ventricular dysfunction is present. In this particular group of patients, coronary bypass surgery has been shown to improve 10 year survival. Coronary angioplasty has been compared with surgical treatment in many clinical trials. The medium-term survival is the same in both groups, but with a higher number of repeat procedures except in diabetic patients in whom mortality is higher after angioplasty. The use of coronary stents should reduce the number of post-angioplasty procedures. Constant technical improvements, the introduction of surgery without cardiopulmonary bypass, combined revascularisation procedures, new antiplatelet drugs, the absence of long-term comparative results, all this results in a personalized choice of revascularisation procedure based on the overall clinical and angiography features of each particular case.

[Coronary angioplasty: methods of evaluation]. / L'angioplastie coronaire; méthodes d'évaluation.

Coronary angioplasty is sometimes thought to be insufficiently validated considering the considerable development it has undergone and its place in modern cardiological practice. Nevertheless, several randomised clinical trials comparing angioplasty with medical therapy in stable angina (ACME) and with surgical treatment in stable and unstable angina (RITA) have provided more scientific support for the technique. The serious perioperative complications have become rare, the limiting factor being restenosis which is responsible for a large number of clinical recurrences and the reappearance of documented myocardial ischaemia. It is therefore logical to make restenosis the first objective of evaluation of PTCA. There are two possible approaches to this problem. The first relies on automatic quantitative operator-independent angiography as a gold standard. However, this method is methodologically complex, technically fastidious and only takes into consideration the anatomical appearances, the correlations with clinical outcome and prognosis of which are poor. It allows measurement of the amplitude of the process which is an unquestionable advantage, but it is only a partial view of the problem. The second method considers that only stenosis causing ischaemia is significant and that the criterion of evaluation should be the rate of new events and that the necessity of repeated attempts at revascularisation is the criterion of failure of the method. This overlooks the possibility of an anti-restenosis drug producing clinical results independents of its anatomical effect. Both methods have their advantages and drawbacks, which necessitates using them both in all trials of new tools or new molecules designed to prevent restenosis.

[Acute myocardial infarction: recent physiopathological data. 1: acute coronary occlusion]. / Infarctus myocardique aigu: données physiopathologiques récentes. Première partie: l'occlusion coronaire aiguë.

Acute myocardial infarction is the result of sudden coronary occlusion in the absence of a collateral circulation. There main factors are required for this to occur: an acute parietal lesion on a stenosis of variable, sometimes minor, importance; local coronary vasoconstriction and a platelet and fibrin thrombus. Parietal fissuration is the commonest "trigger" of coronary spasm and the thrombotic cascade. All factors of coronary occlusion are potentially reversible--vasodilation--platelet anti-aggregation--physiological fibrinolysis--remodeling and cicatrisation of the plaque, thereby explaining cases of spontaneous regression of occlusion (10% at 1 hour; 20% at 6 hours; 30% at 24 hours; 50 to 70% at 1 year). The pathogenesis of myocardial infarction with angiographically normal coronary arteries may be reviewed and attributed to acute parietal fissuration at a non-significant or angiographically undetectable plaque resulting in occlusive thrombosis. In this case, the role of other pathogenic factors is also discussed (diabetes, oral contraception, haemostatic abnormalities, platelet disorders...).

[Acute myocardial infarction: recent physiopathological data. 2: Left ventricular function]. / Infarctus myocardique aigu: données physiopathologiques récentes. Deuxième partie: la fonction ventriculaire gauche.

Myocardial infarction is an anatomical and therefore functional amputation of some of the myocardial tissues. Moments after acute coronary occlusion, a cascade of metabolic, mechanical and electrical ischaemia related events is observed. Contraction stops and regional left ventricular akinesis (then dyskinesis) occurs in the zone at risk of irreversible myocardial damage. This is partially compensated by hyperkinetic motion of non-ischaemic myocardium. The degree of alteration of the global ejection fraction is the resultant of these akinetic and hyperkinetic wall motions. It is lower in cases of anterior myocardial infarction, of occlusion of the proximal segment of the left anterior descending artery and of multivessel disease. Its eventual outcome depends on coronary blood flow. If the artery responsible is recanalized early, the global ejection fraction stabilises or improves. When this does not happen, the global ejection fraction decreases. The end-diastolic volume, an indicator of left ventricular remodeling, increases in relation to the size of the infarct and to the persistence of coronary artery occlusion. The delay before the appearance of the first irreversible lesions, the rate of their propagation within the myocardial wall and the presence of reperfusion lesions are poorly understood factors in the clinical setting and influence the efficacy of methods of myocardial protection.

[Environmental factors and acute leukemia in children. Apropos of a case-control study carried out in the Rhône-Alpes region]. / Facteurs d'environnement et leucémie aiguë chez l'enfant. A propos d'une étude cas-témoin réalisée dans la région Rhône-Alpes.

To test the large number of hypotheses proposed as causes for childhood leukemia, a case control study was carried out on every child diagnosed for acute leukemia between 1.1.1977 and 12.31.1982, under the age of 15 and living in the region of Lyon (Rhône-Alpes and Saône-et-Loire). Some factors could not be confirmed, possibly in relation with the relatively small sample size (208 cases). Others were confirmed, especially the excess of incidence among 2 to 4 year old children and those belonging to higher socioeconomic groups. Two new factors were identified: the age of the father (over 40 years at child birth) and the profession of the father (manipulation of meat in the few years prior the diagnosis of leukemia in the child).