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1.
Phys Rev Lett ; 97(20): 205006, 2006 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-17155691

RESUMEN

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.

2.
Anim Genet ; 37(3): 189-98, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16734675

RESUMEN

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.


Asunto(s)
Variación Genética , Repeticiones de Microsatélite , Porcinos/genética , Alelos , Animales , Biodiversidad , Cruzamiento , Europa (Continente) , Frecuencia de los Genes , Genotipo , Porcinos/clasificación
3.
Anim Genet ; 37(3): 232-8, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16734682

RESUMEN

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.


Asunto(s)
Polimorfismo Genético , Porcinos/genética , Alelos , Animales , Cruzamiento , Europa (Continente) , Marcadores Genéticos , Genotipo , Heterocigoto , Repeticiones de Microsatélite , Filogenia , Porcinos/clasificación
4.
Ann Chir ; 130(8): 470-6, 2005 Sep.
Artículo en Francés | MEDLINE | ID: mdl-16084483

RESUMEN

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.


Asunto(s)
Carcinoma/complicaciones , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Cuidados Paliativos , Neoplasias Peritoneales/complicaciones , Corticoesteroides/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos/uso terapéutico , Antieméticos/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Grupo de Atención al Paciente , Estudios Prospectivos , Análisis de Supervivencia , Cuidado Terminal , Resultado del Tratamiento
5.
Dev Biol (Basel) ; 114: 147-60, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14677685

RESUMEN

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.


Asunto(s)
Vacunas Bacterianas/uso terapéutico , Enfermedades de los Bovinos/inmunología , Pleuroneumonía Contagiosa/inmunología , África/epidemiología , Animales , Vacunas Bacterianas/efectos adversos , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/prevención & control , Pleuroneumonía Contagiosa/epidemiología , Pleuroneumonía Contagiosa/prevención & control
6.
Presse Med ; 32(5): 203-11, 2003 Feb 08.
Artículo en Francés | MEDLINE | ID: mdl-12610460

RESUMEN

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

Asunto(s)
Cuidados Paliativos , Enfermo Terminal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Recolección de Datos , Interpretación Estadística de Datos , Francia , Hospitalización , Hospitales Universitarios , Humanos , Persona de Mediana Edad , Encuestas y Cuestionarios , Organización Mundial de la Salud
7.
Rev Med Interne ; 23(1): 55-70, 2002 Jan.
Artículo en Francés | MEDLINE | ID: mdl-11859695

RESUMEN

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.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Dolor/tratamiento farmacológico , Administración Oral , Analgésicos Opioides/efectos adversos , Analgésicos Opioides/farmacología , Ensayos Clínicos como Asunto , Preparaciones de Acción Retardada , Fentanilo , Humanos , Hidromorfona/efectos adversos , Hidromorfona/farmacología , Hidromorfona/uso terapéutico , Morfina/efectos adversos , Morfina/farmacología , Morfina/uso terapéutico , Neoplasias/complicaciones , Organización Mundial de la Salud
8.
Phys Rev Lett ; 84(13): 2869-72, 2000 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-11018963

RESUMEN

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.

9.
Phys Rev Lett ; 84(16): 3598-601, 2000 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-11019155

RESUMEN

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.

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