937 resultados para Marks of origin
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Biogeographic studies dealing with Bombyliidae are rare in the literature and no information is available on its origin and early diversification. In this study, we found evidence from molecular phylogeny and from fossil record supporting a Middle Jurassic origin of the Bombylioidea, taken as a starting point to discuss the biogeography and diversification of Crocidiinae. Based on a previously published phylogenetic hypothesis, we performed a Brooks Parsimony Analysis (BPA) to discuss the biogeographical history of Crocidiinae lineages. This subfamily is mostly distributed over arid areas of the early components of the Gondwanaland: Chile and southern Africa, but also in southwestern Palaearctic and southwestern Nearctic. The vicariant events affecting the Crocidiinae biogeography at the generic level seems to be related to the sequential separation of a Laurasian clade from a Gondwanan clade followed by the splitting of the latter into smaller components. This also leads to a hypothesis of origin of the Crocidiinae in the Middle Jurassic, the same period in which other bombyliid lineages are supposed to have arisen and irradiated.
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The aims of this thesis were to better characterize HIV-1 diversity in Portugal, Angola, Mozambique and Cape Verde and to investigate the origin and epidemiological history of HIV-1 in these countries. The impact of these issues in diagnosis, disease progression and susceptibility to ARV therapy was also investigated. Finally, the nature, dynamics and prevalence of transmitted drug resistance (TDR) was determined in untreated HIV-1 infected patients. In Angola, practically all HIV-1 genetic forms were found, including almost all subtypes, untypable (U) strains, CRFs and URFs. Recombinants (first and second generation) were present in 47.1% of the patients. HIV/AIDS epidemic in Angola probably started in 1961, the major cause being the independence war, subsequently spreading to Portugal. In Maputo, 81% of the patients were infected with subtype C viruses. Subtype G, U and recombinants such as CRF37_cpx, were also present. The results suggest that HIV-1 epidemic in Mozambique is evolving rapidly in genetic complexity. In Cape Verde, where HIV-1 and HIV-2 co-circulate, subtype G is the prevailed subtype. Subtypes B, C, F1, U, CRF02_AG and other recombinant strains were also found. HIV-2 isolates belonged to group A, some being closely related to the original ROD isolate. In all three countries numerous new polymorphisms were identified in the RT and PR of HIV-1 viruses. Mutations conferring resistance to the NRTIs or NNRTIs were found in isolates from 2 (2%) patients from Angola, 4 (6%) from Mozambique and 3 (12%) from Cape Verde. None of the isolates containing TDR mutations would be fully sensitive to the standard first-line therapeutic regimens used in these countries. Close surveillance in treated and untreated populations will be crucial to prevent further transmission of drug resistant strains and maximize the efficacy of ARV therapy. In Portugal, investigation of a seronegative case infection with rapid progression to AIDS and death revealed that the patient was infected with a CRF14_BG-like R5-tropic strain selectively transmitted by his seropositive sexual partner. The results suggest a massive infection with a highly aggressive CRF14_BG like strain and/or the presence of an unidentified immunological problem that prevented the formation of HIV-1-specific antibodies. Near full-length genomic sequences obtained from three unrelated patients enabled the first molecular and phylogenomic characterization of CRF14_BG from Portugal; all sequences were strongly related with CRF14_BG Spanish isolates. The mean date of origin of CRF14_BG was estimated to be 1992. We propose that CRF14_BG emerged in Portugal in the early 1990s, spread to Spain in late 1990s as a consequence of IDUs migration and then to the rest of Europe. Most CRF14_BG strains were predicted to use CXCR4 and were associated with rapid CD4 depletion and disease progression. Finally, we provide evidence suggesting that the X4 tropism of CRF14_BG may have resulted from convergent evolution of the V3 loop possibly driven by an effective escape from neutralizing antibody response.
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BACKGROUND: Tuberculosis (TB) screening in prisons is recommended, but the appropriate methods remain controversial. Studies evaluating screening in remand prisons arc scarce. METHOD: Between 1997 and 2001, voluntary screening based on the tuberculin skin test (TST) was offered to all prisoners on entry into the largest remand prison in Switzerland. Prisoners with positive results underwent chest X-rays. We analysed this information collected in an anonymous database. RESULTS: A total of 4890 prisoners entered the prison and were eligible for screening; 3779 (77.3%) had TST performed on average 9 days after arrival: 46.9% were positive (induration >= 10 mm). Positive TST rates were similar over the 5 years. Women were more likely to have a negative TST (60.4%) than men (47.7%; P < 0.001, Pearson's chi(2) 16.5). Positive TSTs varied according to the prisoner's country of origin (64% for sub-Saharan Africa, 57% for Eastern Europe, 56% for North Africa, 51% for Asia and 34% for North and West Europe). CONCLUSION: The percentage of TST-positive subjects was high, and most did not receive preventive treatment for latent TB. The usefulness of systematic TST for all prisoners on entry is limited, as diagnosis of TB disease usually remains the priority in prisons. Keywords
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Genetic structure of populations of Pissodes castaneus (De Geer) (Coleoptera, Curculionidae) using amplified fragment length polymorphism. The objective of this study was to determine the genetic structure of populations of Pissodes castaneus from different areas and on different species of Pinus using the PCR-AFLP technique. Twenty samples were analyzed, representing 19 populations from Brazil and one from Florence, Italy, which is the region of origin of P. castaneus. The four combinations of primers generated a total of 367 fragments of DNA, and 100% of polymorphic loci, indicating high degree of molecular polymorphism. The dendrogram did not reveal trends for grouping the populations in relation to origin. The low genetic similarity (0.11 between the most distant groups) and genetic distances of 0.13 and 0.44 for 10 out of the 20 samples may indicate several founding events or multiple introductions of heterogeneous strains into Brazil. The allelic fixation index (Fst) was 0.3851, considered high, and the number of migrants (Nm) was 0.3991, indicating low gene flow among populations. The highest genetic distances were between the population from Irani, SC and Cambará do Sul, RS and Bituruna, PR, indicating an independent founding event or a particular allelic fixation in the former location. The high genetic diversity among populations points out that the populations are genetically heterogeneous with a diverse gene pool in the surveyed areas, what makes them to respond differently to control measures.
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Undocumented migrants, meaning migrants without a legal residency permit, come to Geneva from countries with high tuberculosis (TB) incidence. We estimate here whether being undocumented is a determinant of TB, independently of origin. Cross-sectional study including undocumented migrants in a TB screening program in 2002; results were compared to 12,904 age and frequency matched participants in a general TB screening program conducted at various workplaces in Geneva, Switzerland from 1992 to 2002. A total of 206 undocumented migrants (36% male, 64% female, mean age 37.8 years (SD 11.8), 82.5% from Latin America) participated in the TB screening program. Compared to legal residents, undocumented migrants had an adjusted OR for TB-related fibrotic signs of 1.7 (95% CI 0.8;3.7). The OR of TB-related fibrotic signs for Latin American (vs. other) origin was 2.7 (95% CI 1.6;4.7) among legal residents and 5.5 (95% CI 2.8;10.8) among undocumented migrants. Chest X-ray screening identified a higher proportion of TB-related fibrotic signs among Latin Americans, independently of their residency status.
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BACKGROUND: Uveal metastasis is the most common intraocular malignancy. METHODS: This was a retrospective study of all patients with uveal metastases referred to the Liverpool Ocular Oncology Centre between January 2007 and December 2012. Biopsy was performed as a primary investigation if the clinical examination suggested metastasis with no evidence of any extraocular metastases. RESULTS: Ninety-six patients (109 eyes) were included. Breast and lung carcinomas were the most common primary malignancies, affecting 41 and 27 patients, respectively. The median time interval between detection of primary cancer and uveal metastasis was 24 months (range 1-288 months). Thirty-nine patients underwent ocular biopsy, confirming the diagnosis in all patients. The biopsy indicated the site of origin in 24 out of the 27 without a known primary tumour. In 7 of these 27 cases, previous systemic investigations had failed to identify the primary tumour. Seventy-three patients received external beam irradiation; two patients received photodynamic therapy; and two patients had Ru-106 plaque radiotherapy. The visual acuity was stable or improved in 75.5% of the cases. CONCLUSIONS: Immediate biopsy provides a quick diagnosis that may expedite treatment and improve any opportunities for conserving vision while facilitating the general oncologic management on these patients.
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En Suisse, le nombre de filles et de femmes migrantes excisées au cours de leur enfance dans leur pays d'origine ou menacées de mutilations génitales rituelles est estimé à 6-7000. Les professionnels de la santé en tant qu'interlocuteurs privilégiés doivent donc être en mesure de répondre aux questions y relatives, non seulement durant l'adolescence, mais aussi dans toutes les phases de la vie. L'absence d'information ou de transmission par des aînées aussi bien avant l'excision qu'au moment de la maturité sexuelle en fait souvent un événement biographique traumatisant. Arrivées en Suisse, le décalage entre les attentes socioculturelles et familiales et le vécu individuel, influencé par le pays d'accueil, peut s'avérer particulièrement difficile à vivre pour les jeunes filles concernées. In Switzerland, the estimated number of survivors after traditional female genital mutilation in the country of origin or girls and adult women at risk is 6-7000. Health professionals must be able to respond adequately to their questions not only during adolescence but through out the different periods of life. The lack of information or transmission by the seniors as well before the excision as at the time of sexual maturity contributes in a large measure to the frequent biographic trauma. It can be very difficult for the girls to deal with the gap between socio cultural and family expectations and their individual life experience in Switzerland.
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Background and aim of the study: Genomic gains and losses play a crucial role in the development and progression of DLBCL and are closely related to gene expression profiles (GEP), including the germinal center B-cell like (GCB) and activated B-cell like (ABC) cell of origin (COO) molecular signatures. To identify new oncogenes or tumor suppressor genes (TSG) involved in DLBCL pathogenesis and to determine their prognostic values, an integrated analysis of high-resolution gene expression and copy number profiling was performed. Patients and methods: Two hundred and eight adult patients with de novo CD20+ DLBCL enrolled in the prospective multicentric randomized LNH-03 GELA trials (LNH03-1B, -2B, -3B, 39B, -5B, -6B, -7B) with available frozen tumour samples, centralized reviewing and adequate DNA/RNA quality were selected. 116 patients were treated by Rituximab(R)-CHOP/R-miniCHOP and 92 patients were treated by the high dose (R)-ACVBP regimen dedicated to patients younger than 60 years (y) in frontline. Tumour samples were simultaneously analysed by high resolution comparative genomic hybridization (CGH, Agilent, 144K) and gene expression arrays (Affymetrix, U133+2). Minimal common regions (MCR), as defined by segments that affect the same chromosomal region in different cases, were delineated. Gene expression and MCR data sets were merged using Gene expression and dosage integrator algorithm (GEDI, Lenz et al. PNAS 2008) to identify new potential driver genes. Results: A total of 1363 recurrent (defined by a penetrance > 5%) MCRs within the DLBCL data set, ranging in size from 386 bp, affecting a single gene, to more than 24 Mb were identified by CGH. Of these MCRs, 756 (55%) showed a significant association with gene expression: 396 (59%) gains, 354 (52%) single-copy deletions, and 6 (67%) homozygous deletions. By this integrated approach, in addition to previously reported genes (CDKN2A/2B, PTEN, DLEU2, TNFAIP3, B2M, CD58, TNFRSF14, FOXP1, REL...), several genes targeted by gene copy abnormalities with a dosage effect and potential physiopathological impact were identified, including genes with TSG activity involved in cell cycle (HACE1, CDKN2C) immune response (CD68, CD177, CD70, TNFSF9, IRAK2), DNA integrity (XRCC2, BRCA1, NCOR1, NF1, FHIT) or oncogenic functions (CD79b, PTPRT, MALT1, AUTS2, MCL1, PTTG1...) with distinct distribution according to COO signature. The CDKN2A/2B tumor suppressor locus (9p21) was deleted homozygously in 27% of cases and hemizygously in 9% of cases. Biallelic loss was observed in 49% of ABC DLBCL and in 10% of GCB DLBCL. This deletion was strongly correlated to age and associated to a limited number of additional genetic abnormalities including trisomy 3, 18 and short gains/losses of Chr. 1, 2, 19 regions (FDR < 0.01), allowing to identify genes that may have synergistic effects with CDKN2A/2B inactivation. With a median follow-up of 42.9 months, only CDKN2A/2B biallelic deletion strongly correlates (FDR p.value < 0.01) to a poor outcome in the entire cohort (4y PFS = 44% [32-61] respectively vs. 74% [66-82] for patients in germline configuration; 4y OS = 53% [39-72] vs 83% [76-90]). In a Cox proportional hazard prediction of the PFS, CDKN2A/2B deletion remains predictive (HR = 1.9 [1.1-3.2], p = 0.02) when combined with IPI (HR = 2.4 [1.4-4.1], p = 0.001) and GCB status (HR = 1.3 [0.8-2.3], p = 0.31). This difference remains predictive in the subgroup of patients treated by R-CHOP (4y PFS = 43% [29-63] vs. 66% [55-78], p=0.02), in patients treated by R-ACVBP (4y PFS = 49% [28-84] vs. 83% [74-92], p=0.003), and in GCB (4y PFS = 50% [27-93] vs. 81% [73-90], p=0.02), or ABC/unclassified (5y PFS = 42% [28-61] vs. 67% [55-82] p = 0.009) molecular subtypes (Figure 1). Conclusion: We report for the first time an integrated genetic analysis of a large cohort of DLBCL patients included in a prospective multicentric clinical trial program allowing identifying new potential driver genes with pathogenic impact. However CDKN2A/2B deletion constitutes the strongest and unique prognostic factor of chemoresistance to R-CHOP, regardless the COO signature, which is not overcome by a more intensified immunochemotherapy. Patients displaying this frequent genomic abnormality warrant new and dedicated therapeutic approaches.
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X-chromosome inactivation (XCI) is a dosage compensation mechanism that silences the majority of genes on one X chromosome in each female cell. To characterize epigenetic changes that accompany this process, we measured DNA methylation levels in 45,X patients carrying a single active X chromosome (X(a)), and in normal females, who carry one X(a) and one inactive X (X(i)). Methylated DNA was immunoprecipitated and hybridized to high-density oligonucleotide arrays covering the X chromosome, generating epigenetic profiles of active and inactive X chromosomes. We observed that XCI is accompanied by changes in DNA methylation specifically at CpG islands (CGIs). While the majority of CGIs show increased methylation levels on the X(i), XCI actually results in significant reductions in methylation at 7% of CGIs. Both intra- and inter-genic CGIs undergo epigenetic modification, with the biggest increase in methylation occurring at the promoters of genes silenced by XCI. In contrast, genes escaping XCI generally have low levels of promoter methylation, while genes that show inter-individual variation in silencing show intermediate increases in methylation. Thus, promoter methylation and susceptibility to XCI are correlated. We also observed a global correlation between CGI methylation and the evolutionary age of X-chromosome strata, and that genes escaping XCI show increased methylation within gene bodies. We used our epigenetic map to predict 26 novel genes escaping XCI, and searched for parent-of-origin-specific methylation differences, but found no evidence to support imprinting on the human X chromosome. Our study provides a detailed analysis of the epigenetic profile of active and inactive X chromosomes.
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The variety of soils in the State of Acre is wide and their chemical profiles are still not fully understood. The nature of the material of origin of these soils is indicated by the high aluminium (Al) content, commonly associated with high calcium (Ca) and magnesium (Mg) contents. The study objective was to use different methods to quantify Al in soils from toposequences formed from material of a sedimentary nature originating from the Solimões Formation, in Acre, Brazil. Trenches were opened at three distinct points in the landscape: shoulder, backslope and footslope positions. Soil samples were collected for physical, chemical, mineralogical analyses. The Al content was quantified using different methods. High Al contents were found in most of these horizons, associated with high Ca and Mg levels, representing the predominant cations in the sum of exchangeable bases. The mineralogy indicates that the soils are still in a low weathering phase, with the presence of significant quantities of 2:1 minerals. Similar Al contents were determined by the methods of NaOH titration, xylenol orange spectrometry and inductively coupled plasma optical emission spectrometry. However, no consistent data were obtained by the pyrocatechol violet method. Extraction with KCl overestimated the exchangeable Al content due to its ability to extract the non-exchangeable Al present in the smectite interlayers. It was observed that high Al contents are related to the instability of the hydroxyl-Al smectite interlayers.
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Background: there is little information regarding the health status of migrants compared to subjects who remained in their country of origin. The aim was to compare Portuguese living in Porto (Portugal) with Portuguese migrants living in Lausanne (Switzerland). Design: cross-sectional studies conducted in Porto (EpiPorto, n=1150) and Lausanne (CoLaus, n=388) among Portuguese subjects aged between 35 and 65 years. Methods: body mass index, blood pressure, cholesterol and glucose levels were assessed using standardized procedures. Educational level, antihypertensive, hypocholesterolemic and antidiabetic treatments were collected using questionnaires. Results: Portuguese living in Lausanne were younger, more frequently male and had a lower education than Portuguese living in Porto. After multivariate adjustment, Portuguese living in Porto had a higher likelihood of being obese [Odds ratio and 95% confidence interval: 1.40 (1.01-1.94)] or abdominal obese [OR: 1.40 (1.02-1.93)] than Portuguese living in Lausanne. Portuguese living in Porto had a higher likelihood of being hypertensive than Portuguese living in Lausanne [OR: 1.38 (1.01-1.90)], while no differences were found regarding hypertension management and control. Portuguese living in Porto had a higher likelihood of being hypercholesterolemic [OR: 1.40 (1.06-1.85)] and were less likely to be treated [OR: 0.47 (0.27-0.83)] and controlled [OR: 0.47 (0.27-0.83)] than Portuguese living in Lausanne. Finally, no differences were found regarding smoking, prevalence and management of diabetes. Conclusion: Portuguese living in Lausanne, Switzerland, present a better cardiovascular risk profile and tend to be better managed regarding their cardiovascular risk factors than Portuguese living in Porto, Portugal.
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How phenomena like helping, dispersal, or the sex ratio evolve depends critically on demographic and life-history factors. One phenotype that is of particular interest to biologists is genomic imprinting, which results in parent-of-origin-specific gene expression and thus deviates from the predictions of Mendel's rules. The most prominent explanation for the evolution of genomic imprinting, the kinship theory, originally specified that multiple paternity can cause the evolution of imprinting when offspring affect maternal resource provisioning. Most models of the kinship theory do not detail how population subdivision, demography, and life history affect the evolution of imprinting. In this work, we embed the classic kinship theory within an island model of population structure and allow for diverse demographic and life-history features to affect the direction of selection on imprinting. We find that population structure does not change how multiple paternity affects the evolution of imprinting under the classic kinship theory. However, if the degree of multiple paternity is not too large, we find that sex-specific migration and survival and generation overlap are the primary factors determining which allele is silenced. This indicates that imprinting can evolve purely as a result of sex-related asymmetries in the demographic structure or life history of a species.
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Peripheral T-cell lymphomas (PTCLs) represent a heterogeneous group of more than 20 neoplastic entities derived from mature T cells and natural killer (NK) cells involved in innate and adaptive immunity. With few exceptions these malignancies, which may present as disseminated, predominantly extranodal or cutaneous, or predominantly nodal diseases, are clinically aggressive and have a dismal prognosis. Their diagnosis and classification is hampered by several difficulties, including a significant morphological and immunophenotypic overlap across different entities, and the lack of characteristic genetic alterations for most of them. Although there is increasing evidence that the cell of origin is a major determinant for the delineation of several PTCL entities, however, the cellular derivation of most entities remains poorly characterized and/or may be heterogeneous. The complexity of the biology and pathophysiology of PTCLs has been only partly deciphered. In recent years, novel insights have been gained from genome-wide profiling analyses. In this review, we will summarize the current knowledge on the pathobiological features of peripheral NK/T-cell neoplasms, with a focus on selected disease entities manifesting as tissue infiltrates primarily in extranodal sites and lymph nodes.
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La production endogène à long terme de chaleur, même au repos, est une adaptation que l'on retrouve chez les animaux à sang chaud (les oiseaux et les mammifères). Cette production de chaleur a comme but le maintien d'une température constante du corps indépendamment de la température extérieure. A cette fin, les mammifères ont développé une forme de tissu spécialisé nommé tissu adipeux brun (BAT). Ce tissu est responsable de la conversion de nourriture en chaleur, procédé appelé thermogenèse sans frisson (NST = non-shivering thermogenesis). Durant ce procédé la uncoupling protein 1 (UCP1) convertit, au sein des mitochondries, la nourriture en chaleur au lieu de produire de l'ATP, molécule utilisée comme énergie cellulaire. On suppose que cette inefficacité de la conversion de la nourriture en ATP dans le BAT influence l'homéostasie de l'énergie, l'allocation des ressources ainsi que la régulation de processus gourmant en énergie comme la croissance et la reproduction. Afin de maintenir une température du corps constante, les mammifères doivent ajuster leur NST en fonction de la température ambiante. La NST devrait être donc plus importante que la croissance et la reproduction durant l'hiver que lors l'été/à haute altitude qu'à basse altitude. En effet, plusieurs études ont déjà démontré la dépendance de la NST aux divers paramètres environnementaux. Par contre, l'héritabilité de la NST ainsi que sa relation avec d'autres traits de caractère, ne sont que très peu connus, ceci malgré l'importance d'une telle information afin de pouvoir comprendre son potentiel évolutif. L'étude de l'importance évolutive et écologique sur la NST chez les campagnols des champs (Microtus arvalis) fut donc le but cette thèse de doctorat. Grâce aux informations collectées sur 4 générations de campagnols (chapitre 1), une dépendance saisonnière et journalière de la NST a été démontrée: elle augmente lors des périodes froides et diminue lors de la lactation. On a démontré que bien qu'étant plastique, la variation de la NST a une composante génétique significative. Elle est corrélée avec le taux d'activité métabolique au repos indiquant des contraintes intrinsèques. A l'aide d'une expérience de jardin commune, on a pu démontrer dans le chapitre 2 que les campagnols habitant en altitude ont une capacité génétique de thermogenèse sans frisson plus haute que celles de basse altitude. Ils produisent des portées plus petites et leur descendance grandit moins vite, surtout à partir du 10ème jour ce qui coïncide avec le début de la production de chaleur endogène. En choisissant artificiellement des campagnols avec une NST faible ou grande, on a pu démontrer une relation entre la NST et la développement de la masse corporelle. Les campagnols avec une haute NST grandissent plus lentement et sont plus légères à l'âge adulte que celles ayant une basse NST. A l'aide d'un croisement interligne entre les campagnols sélectionnés (avec basse et haute NST), on a pu montrer dans le chapitre 3 des effets « parent-of-origin >> du développement massique de la descendance, indiquant une empreinte génétique parentale. Cela veut dire que l'expression d'un allele dépend de l'origine parentale. De plus, des effets « parent-of-origin » des taux de base de norépinephrine et d'irisine ont pu être trouvés. Ces hormones sont connues pour influencer non seulement la TSF mais aussi d'autres caractéristiques. Ces influences ouvrent la voie à de nouvelles études sur la relation entre la TSF et l'histoire de vie. Dans le chapitre 4 on a démontré des effets à long terme de l'allocation des ressources en manipulant la taille des portées qui ont abouti à des différences dans l'investissement dans la reproduction et de la croissance de la descendance à la fois dans le cas de la reproduction manipulé et aussi dans le non - manipulée entre les femelles avec portées agrandies et réduites. Ensemble, ces résultats mettent en évidence le rôle central de la NST dans l'allocation des ressources sur la base d'un compromis entre le maintien et la croissance et ainsi transforme l'histoire de vie des mammifères. Ces études montrent comment les mammifères peuvent répondre rapidement à court et à long terme (c'est-à-dire par des réponses génétiques ou plastiques) à un changement rapide du climat. On montre aussi qu'il y a probablement une corrélation entre l'histoire de vie et des changements du comportement. Finalement mes résultats ont montré un lien étroit entre la NST et la croissance et les dimensions du corps. Ces résultats indiquent que le tissu adipeux brun et la NST pourraient être une cible thérapeutique intéressante pour traiter l'obésité.
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El presente trabajo pretende mostrar los resultados de un estudio cuya intención era identificar posibles variables que afectan a los procesos y estrategias de integración laboral de personas procedentes de otros países; las necesidades formativas en relación al colectivo de referencia y ampliar el conocimiento del fenómeno en aras de la intervención psicoeducativa y social. A partir de una metodología de investigación de orientación cualitativa se ha concluido que las diferencias en cuanto a las estrategias de integración y sus logros están más determinadas por los niveles de cualificación en el país de origen que por las propias diferencias culturales. The article shows the results of a study carried out by the authors to identify possible variables that affect the processes and strategies of occupational integration of people coming from other countries, to establish training needs in relation to the reference group and to extend the knowledge of the phenomenon for the sake of the educational and social intervention. Using a qualitative research methodology, it was concluded that the differences in integration strategies and their accomplishments are better explained by the levels of qualification attained in the country of origin than by cultural differences.