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1.
Data Brief ; 9: 803-806, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27844047

RESUMEN

The dataset supplied in this article provides the spatial location and the species composition of urban trees belonging to three coniferous genera (Pinus, Cedrus and Pseudotsuga) inventoried in 5 districts of the city of Orléans (France). A total of 9321 trees were georeferenced. The most abundant species was the black pine Pinus nigra for which a total of 2420 trees were observed. Other common species were the scots pine P. sylvestris, the Douglas-fir Pseudotsuga menziesii and different species of the genus Cedrus. The data supplied in this article are related to "A citywide survey of the pine processionary moth Thaumetopoea pityocampa spatial distribution in Orléans (France)" by J.-P. Rossi, V. Imbault, T. Lamant, J. Rousselet,) [3].

2.
J Gynecol Obstet Biol Reprod (Paris) ; 41(4): 383-6, 2012 Jun.
Artículo en Francés | MEDLINE | ID: mdl-22227233

RESUMEN

Pheochromocytomas are rare but potentially lethal tumors responsible for malignant hypertension. They may be encountered by gynecologists and obstetricians. The diagnosis is difficult because it can be mistaken for diseases more frequent like preeclampsia or other pelvic tumors. We report two cases highlighting clinical clues such as labile hypertension, headache, sweating, palpitations and failure to respond to conventional treatment should prompt physicians to screen patients for pheochromocytoma by measuring the 24-hour urinary catecholamines. The surgery must be performed after using an appropriate preoperative treatment, in order not to trigger lethal outcome. During pregnancy, C-section is recommended.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/diagnóstico , Feocromocitoma/diagnóstico , Complicaciones Neoplásicas del Embarazo/diagnóstico , Neoplasias de las Glándulas Suprarrenales/mortalidad , Neoplasias de las Glándulas Suprarrenales/fisiopatología , Adulto , Diagnóstico Diferencial , Extracción Obstétrica , Resultado Fatal , Femenino , Ginecología/tendencias , Humanos , Hipertensión Inducida en el Embarazo/diagnóstico , Hipertensión Inducida en el Embarazo/mortalidad , Recién Nacido , Obstetricia/tendencias , Feocromocitoma/mortalidad , Feocromocitoma/fisiopatología , Embarazo , Complicaciones Neoplásicas del Embarazo/mortalidad
3.
J Evol Biol ; 24(1): 146-58, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20964783

RESUMEN

A plausible case of allochronic differentiation, where barrier to gene flow is primarily attributable to a phenological shift, was recently discovered in Portugal for the pine processionary moth Thaumetopoea pityocampa. Previous results suggested that the observed 'summer population' (SP) originated from the sympatric winter population (WP). Our objectives were to finely analyse these patterns and test their stability in time, through field monitoring and genetic analyses of larvae and adults across different years. Reproductive activity never overlapped between SP and WP. Microsatellites showed a clear differentiation of the SP, consistent with a strong reduction in gene flow owing to the phenological shift. Assignment tests suggested that some individuals shift from the SP to the WP phenology, causing some hybridization. We discuss these patterns and their maintenance over time. This could be a first stage of allochronic speciation, and SP should be considered as a distinct phenological race.


Asunto(s)
Especiación Genética , Mariposas Nocturnas/genética , Migración Animal , Animales , Vuelo Animal , Efecto Fundador , Flujo Génico , Genotipo , Hibridación Genética , Larva/genética , Repeticiones de Microsatélite , Mariposas Nocturnas/fisiología , Estaciones del Año , Conducta Sexual Animal
4.
Mol Ecol ; 16(11): 2273-83, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17561890

RESUMEN

Phylogeographic structure of the eastern pine processionary moth Thaumetopoea wilkinsoni was explored in this study by means of nested clade phylogeographic analyses of COI and COII sequences of mitochondrial DNA and Bayesian estimates of divergence times. Intraspecific relationships were inferred and hypotheses tested to understand historical spread patterns and spatial distribution of genetic variation. Analyses revealed that all T. wilkinsoni sequences were structured in three clades, which were associated with two major biogeographic events, the colonization of the island of Cyprus and the separation of southwestern and southeastern Anatolia during the Pleistocene. Genetic variation in populations of T. wilkinsoni was also investigated using amplified fragment length polymorphisms and four microsatellite loci. Contrasting nuclear with mitochondrial data revealed recurrent gene flow between Cyprus and the mainland, related to the long-distance male dispersal. In addition, a reduction in genetic variability was observed at both mitochondrial and nuclear markers at the expanding boundary of the range, consistent with a recent origin of these populations, founded by few individuals expanding from nearby localities. In contrast, several populations fixed for one single mitochondrial haplotype showed no reduction in nuclear variability, a pattern that can be explained by recurrent male gene flow or selective sweeps at the mitochondrial level. The use of both mitochondrial and nuclear markers was essential in understanding the spread patterns and the population genetic structure of T. wilkinsoni, and is recommended to study colonizing species characterized by sex-biased dispersal.


Asunto(s)
Mariposas Nocturnas/genética , Filogenia , Animales , Conducta Animal , ADN Mitocondrial/genética , Femenino , Variación Genética , Geografía , Haplotipos , Masculino , Repeticiones de Microsatélite , Medio Oriente , Mariposas Nocturnas/fisiología , Análisis de Secuencia de ADN
5.
Heredity (Edinb) ; 97(1): 38-45, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16685280

RESUMEN

A parallel study of the genetic structure of two oligophagous species associated with the same hosts was conducted to determine the main factors shaping the distribution of genetic diversity. The bark beetle Tomicus piniperda and the pine processionary moth (PPM) Thaumetopoea pityocampa are both associated with the genus Pinus and belong to different guilds (xylophagous vs defoliating species). The PPM is an ectophagous species that feeds on the needles of living trees, whereas T. piniperda is endophagous and bores galleries in the inner bark of weakened trees. Both species were sampled in the main regions of France, and their genetic structure was assessed after genotyping with five microsatellite markers. Populations of the PPM were significantly structured. A pattern of isolation by distance was found when distances were calculated as bypassing the Massif Central, whereas no such pattern could be found with raw geographic distances. On the contrary, most populations of T. piniperda were not differentiated. No effect of host species could be detected in either of the two species. We conclude that the two taxa have contrasting effective dispersal rates per generation, and we hypothesize that this reflects the different selection pressures acting on individual fitness via different strategies of host use.


Asunto(s)
Escarabajos/genética , Ecosistema , Mariposas Nocturnas/genética , Pinus/parasitología , Animales , Escarabajos/clasificación , Femenino , Francia , Flujo Génico , Variación Genética , Genética de Población , Geografía , Larva/genética , Repeticiones de Microsatélite/genética , Mariposas Nocturnas/clasificación , Corteza de la Planta
6.
Proc Biol Sci ; 267(1455): 1819-23, 2000 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-11052531

RESUMEN

The haploid complement consists of seven metacentric chromosomes in most diprionid species but has evolved to n = 8 by fission in Neodiprion abietis. This fission generated a small telocentric chromosome and a large pseudoacrocentric chromosome with a short arm carrying a satellite. In situ hybridization indicated that the location of the rRNA gene cluster corresponds to the whole short arm. This suggests that (i) the breaking point was located close to an rRNA gene cluster, and (ii) fission was associated with growth of rDNA. These results suggest rDNA as a preferential breaking point but with a role in the healing of naked chromosome ends.


Asunto(s)
Cromosomas/fisiología , ADN Ribosómico/genética , Evolución Molecular , Himenópteros/genética , Metafase , Animales , Genes de ARNr , Himenópteros/fisiología , Hibridación in Situ , Cariotipificación
7.
Chirurgie ; 123(3): 280-6, 1998 Jun.
Artículo en Francés | MEDLINE | ID: mdl-9752519

RESUMEN

AIM OF THE STUDY: The aim of this study was to evaluate the therapeutic modalities, particularly surgical treatment, for adrenal metastasis of hepatocellular carcinomas. PATIENTS AND METHODS: This series included 13 patients (mean age: 64 years) with hepatocellular carcinoma on cirrhotic liver (n = 8) or healthy liver (n = 5). The adrenal metastasis was synchronous in four cases, metachronous in nine, unilateral in ten cases, and bilateral in three. Resection of the adrenal metastasis was performed in seven patients, combined with the resection of the hepatic carcinoma in three cases or secondarily performed in four. The metastasis was not resected in six patients because of poor liver function or poor patient conditions; two patients were treated with percutaneous ethanol injection, one with radiation and three received only a symptomatic treatment. RESULTS: After adrenalectomy combined with liver resection, two patients died in the postoperative course in relation with pulmonary embolism (n = 1) or acute pancreatitis (n = 1). The mean survival in the five other patients was 38 months after the adrenalectomy and 58.6 months after the liver resection. After percutaneous ethanol injection, one patient survived 47 months and the other one 7 months only. After radiation, the patient survived 18 months. After symptomatic treatment, the mean survival was only 7.3 months. CONCLUSION: The present data suggest that adrenal metastasis, either isolated or associated with a well-controlled intrahepatic recurrence, could be treated surgically when the resection is technically feasible. This aggressive management seems the only chance to offer a long-term survival to selected patients.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/secundario , Carcinoma Hepatocelular/secundario , Neoplasias Hepáticas/cirugía , Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía , Adulto , Anciano , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Femenino , Hepatectomía , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Reoperación
8.
Heredity (Edinb) ; 81 ( Pt 5): 573-8, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9881453

RESUMEN

Earlier cytological investigations characterize the family Diprionidae with a modal chromosome number of seven. This study shows that Diprion pini and D. similis have 14 acrocentric chromosomes (n = 14 for haploid males and 2n = 28 for diploid females). In D. pini, rRNA genes are located on the satellite and the round short arm of the chromosome carrying this segment. We studied six populations with no evidence of chromosomal polymorphism at the species level. Our results disagree with those published previously and reopen the question of karyotype evolution. Chromosome morphology, ISH and C-banding results support the hypothesis of chromosome number doubling by centric fission and not by polyploidization, followed by the growth of short arms by means of pericentromeric DNA amplification.


Asunto(s)
Evolución Biológica , Mapeo Cromosómico , Himenópteros/clasificación , Himenópteros/genética , Animales , Europa (Continente) , Femenino , Haploidia , Cariotipificación , Masculino
9.
Nature ; 370(6489): 446-8, 1994 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-8047163

RESUMEN

Structures possessing spatial asymmetry should act as pumps in the presence of dissipation alone, without the need for macroscopic forces or temperature differences to drive vectorial motion. It has been shown theoretically that particles subjected to an asymmetric periodic potential can display net directional motion even if the space-averaged force is zero. Here we demonstrate such behaviour experimentally. We have studied the behaviour of colloidal particles suspended in solution and exposed to a sawtooth dielectric potential which is turned on and off periodically. The particles exhibit net motion with a velocity that depends on their size, suggesting applications in separation processes for objects in the size range 0.1-5 microns--a range that includes biological structures such as viruses, cells and chromosomes. We furthermore point out the analogy between our device and motor protein assemblies.


Asunto(s)
Coloides , Movimiento (Física) , Electricidad , Tamaño de la Partícula , Poliestirenos , Proteínas , Soluciones
10.
Artículo en Francés | MEDLINE | ID: mdl-3083759

RESUMEN

The aim of this study was to investigate the effects of ranitidine on the pentagastrin stimulated gastric secretion (6 micrograms.kg.h) in 30 patients with duodenal ulcer. The drug was administered directly into the gastric lumen. Five different doses were tested: 15 mg (3 patients), 25 mg (7 patients), 50 mg (6 patients), 75 mg (5 patients), 150 mg (4 patients) and 300 mg (5 patients). Ranitidine produced a dose-dependent inhibition of maximal acid secretion (p less than 0.001). Fifty per cent inhibition was obtained with a dose of 0.342 mg.kg-1 corresponding to a dose of 22 mg for a patient weighing 65 kg. The inhibitory effect resulted from a decrease in both volumes and H+ concentrations, the influence of the later being prevalent at high dosages. A decrease in the peptic secretion has been noticed. For small dosages, it chiefly depends on the reduction of the volumes of gastric secretions, although at high dosages the concentration of pepsin was significantly reduced. These results showed that the ranitidine is a potent antisecretory drug; the dosage of 150 mg twice a day which is considered as the regular treatment for ulcer disease seems adequate. However, the authors suggest that a new controlled therapeutic trial should be started with a dosage of 150 mg per day only, divided in four unequal doses (3 X 25 mg + 75 mg). Furthermore a satisfactory control only of the nocturnal secretion, could be obtained with an unique dose of 100 (or 150) mg at bedtime.


Asunto(s)
Ácido Gástrico/metabolismo , Pentagastrina/antagonistas & inhibidores , Pepsina A/metabolismo , Ranitidina/farmacología , Adulto , Relación Dosis-Respuesta a Droga , Úlcera Duodenal/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad
11.
Gastroenterol Clin Biol ; 7(12): 969-74, 1983 Dec.
Artículo en Francés | MEDLINE | ID: mdl-6662332

RESUMEN

Among 54 patients with radiolucent asymptomatic gallstones treated by chenodeoxycholic acid (CDCA), 32 failures were observed. In 15 cases the size of gallstones did not change. In 11 cases the size of gallstones decreased but dissolution was not complete. In 6 cases the treatment had to be interrupted early because of the side-effects. In 10 patients (8.7 p. 100 of the treated patients) calcifications of gallstones occurred. In 9 patients (16.7 p. 100), a cholecystectomy had to be performed because of complications. The incidence of biliary complications necessitating cholecystectomy was significantly higher (p less than 0.001) in patients in whom CDCA failed to induce changes in gallstone size than in patients in whom CDCA was successful. Overall, a decrease of gallstones size was observed in 61 p. 100 of the 54 treated patients. However complete dissolution occurred in only two thirds of these patients. Patients in whom gallstone size decreased seldom presented with a biliary complication. Our data suggest that, when no obvious diminution of gallstones size is evident within six months of treatment, it is not advisable to continue the administration of CDCA. In case of failure, the responsibility of CDCA in the appearance of calcifications or even of complications necessitating cholecystectomy has to be discussed.


Asunto(s)
Calcinosis/etiología , Ácido Quenodesoxicólico/administración & dosificación , Colelitiasis/tratamiento farmacológico , Ácido Quenodesoxicólico/efectos adversos , Colecistectomía , Colelitiasis/cirugía , Humanos
12.
Gastroenterol Clin Biol ; 7(6-7): 605-9, 1983.
Artículo en Francés | MEDLINE | ID: mdl-6873581

RESUMEN

Dissolution of gallstones was observed 33 times in 22 patients. For 11 of them a recurrent lithiasis was dissolved by means of a second or third medical treatment. 21 patients have been followed for 3 to 6 years (median over 4 years). Without longstanding treatment the recurrence rate was 50 p. 100 in 3 years and 87.5 p. 100 in 6 years. Most of the patients should have relapsed in less than 9 years. Recurrences were always successfully treated with the same treatment but relapsed if the treatment was stopped (21 recurrences in 14 patients). A-1 month every 4 months-long standing treatment did not prevent recurrences in 8 patients whereas treatment every other month prevented recurrences in 5. It is therefore suggested to give long treatment after dissolution of gallstones to avoid recurrences. Its duration should be undefinite. Alternatives might include: 1) repeated dissolving treatments in case of recurrences, if relapses occur lately; 2) or longstanding treatment in case of early recurrences.


Asunto(s)
Ácido Quenodesoxicólico/uso terapéutico , Colelitiasis/tratamiento farmacológico , Adulto , Anciano , Colelitiasis/prevención & control , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia
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