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1.
Front Genet ; 13: 963341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212150

RESUMO

Background: Climate change will have significant consequences for species. Species range shifts induce the emergence of new hybrid zones or the spatial displacement of pre-existing ones. These hybrid zones may become more porous as alleles are passed from one species to another. Currently, hybridization between highly divergent species living in sympatry seems extremely limited. Indeed, this phenomenon involves breaking two barriers. The first is the pre-mating barrier, related to the reproductive phenology of the two species. The second is the post-zygotic barrier, related to the genetic divergence between these species. Here, we were interested in identifying new hybridization patterns and potential implications, especially in the context of environmental modifications. Methods: We sampled Telestes souffia and Parachondrostoma toxostoma wild specimens from different locations across France and genotyped them for SNP markers. We identified discriminant loci using F1-hybrid specimens and parental species and performed principal component analysis and Bayesian model-based clustering to analyze phylogenetic information. Furthermore, we assessed deviation in allele frequency from F1 to F2 and for Hardy-Weinberg equilibrium for F2 and assessed gene function associated with two F2 cohorts. Results: We demonstrate that by breaking the ecological barrier, massive introgressive hybridization is possible between two endemic lineages of Cyprinidae belonging to two distinct genera. For both cohorts studied (=2 cm and >2 cm), a large majority of loci (>88%) presented no deviation in allele frequency and no departure from the Hardy-Weinberg equilibrium. For individuals beyond the 2 cm stage, two phenomena were observed. The first was an allelic imbalance in favor of P. toxostoma, for some genomic regions, with genes involved in developmental regulatory processes, cytoskeletal organization, and chromosome organization. The second was an excess of heterozygous loci coupled with an equilibrium of allelic frequencies for genes involved in immune response and kidney/liver development. Moreover, the 2 cm-sized specimens with high mortality yielded a particular genomic signature. Conclusion: Our study displayed important results for understanding the early stages of hybridization between divergent lineages and predicting the emergence of future hybrid zones in the wild. Moreover, this hybridization generates a wide spectrum of hybrids that are a potential source of important evolutionary novelties.

2.
J Dairy Sci ; 105(1): 301-312, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34763916

RESUMO

Urine is a highly suitable biological matrix for metabolomics studies. Total collection for 24-h periods is the gold standard as it ensures the presence of all metabolites excreted throughout the day. However, in animal studies, it presents limitations related to animal welfare and also due to alterations of the metabolome originating from the use of acid for preventing microbial growth or microbial contamination. In this study, we investigated whether spot urine collection is a practical alternative to total collection for metabolomic studies in lactating cows. For this purpose, we collected urine samples from 4 lactating Holstein cows fed 4 diets in a 4 × 4 Latin square design. Urine was collected for 24 h using a collecting device (i.e., total collection) or collected once per day 4 h after the morning feeding (i.e., spot urine collection). Dietary treatments differed by the amount of nitrogen content (high vs. low) and by the nature of the energy (starch vs. fiber). Urine metabolome was analyzed by 2 untargeted complementary methods, nuclear magnetic resonance and hydrophilic-interaction liquid chromatography (HILIC) coupled to a time-of-flight mass spectrometer, and by 1 targeted method, HILIC-tandem mass spectrometry. Although sampling technique had an effect on the abundance of metabolites detected, spot urine samples were equally capable of showing differences in urine metabolome than samples from total collection. When considering nitrogen levels in the diet, the robustness and precision for discriminating high- and low-nitrogen diets was equally achieved with both sampling techniques. A total of 22 discriminant metabolites associated with the N level of diets were identified from untargeted HILIC coupled to a time-of-flight mass spectrometer (n = 9) and nuclear magnetic resonance (n = 11), and 2 from targeted HILIC-tandem mass spectrometry. Alternatively, starch or fiber in the diet induced less changes in the metabolome that were not clearly discriminated independently of the sampling technique. We concluded that spot urine collection can successfully reveal differences in the urine metabolome elicited by dietary N levels and be used as a substitute of total urinary 24-h collection for metabolomic studies.


Assuntos
Lactação , Coleta de Urina , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Feminino , Metaboloma , Metabolômica , Leite , Nitrogênio/metabolismo , Rúmen/metabolismo , Coleta de Urina/veterinária
3.
Braz. j. med. biol. res ; 55: e11821, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1364561

RESUMO

Evidence has shown that women with type 2 diabetes mellitus (T2DM) have a greater risk of cardiovascular complications compared with men, but this sex difference is not clearly understood. This study assessed the microvascular function and circulatory biomarkers in postmenopausal women (PMW) with T2DM compared with diabetic men and their non-diabetic counterparts. Sixty participants were divided into nondiabetic PMW, PMW with T2DM, non-diabetic men, and diabetic men. Microvascular function was assessed using non-invasive equipment (EndoPAT®) and reported as reactive hyperemia index (RHI). Anthropometric and cardiovascular parameters were also measured. Two-way ANOVA was performed using sex (women or men) and T2DM (non-diabetic and diabetic) as the two factors. RHI impairment (1.97±0.14) was detected in diabetic PMW compared with women without T2DM (2.5±0.13) accompanied by lower adiponectin levels (T2DM: 9.3±1.2 and CTL: 13.8±1.8 ug/mL, P<0.05). An increase in the Nε-carboxymethyllysine (CML), nitrate/nitrite, and C-reactive protein (CRP) levels were observed in diabetic PMW compared to the other groups. Although a poor glycemia control was seen in diabetic men, neither RHI nor circulatory biomarkers were affected by T2DM. Multiple linear regression stratified by sex and T2DM identified some variables with RHI only in PMW with T2DM: HbA1c (P=0.003), body mass index (P=0.029), CML (P=0.032), and CRP (P=0.006). Diabetic PMW were more susceptible to the deleterious effects of hyperglycemia than men, showing microvascular dysfunction with high levels of pro-inflammatory mediators (CML and CRP) and a lower adiponectin concentration.

4.
Phys Rev Lett ; 124(20): 202502, 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32501052

RESUMO

Taking benefit of the R3B/SOFIA setup to measure the mass and the nuclear charge of both fission fragments in coincidence with the total prompt-neutron multiplicity, the scission configurations are inferred along the thorium chain, from the asymmetric fission in the heavier isotopes to the symmetric fission in the neutron-deficient thorium. Against all expectations, the symmetric scission in the light thorium isotopes shows a compact configuration, which is in total contrast to what is known in the fission of the heavier thorium isotopes and heavier actinides. This new main symmetric scission mode is characterized by a significant drop in deformation energy of the fission fragments of about 19 MeV, compared to the well-known symmetric scission in the uranium-plutonium region.

5.
Actas urol. esp ; 44(3): 164-171, abr. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-192965

RESUMO

INTRODUCCIÓN: En pacientes con cáncer de próstata un NLR elevado parece asociarse a una peor supervivencia. Abiraterona es un tratamiento hormonal de nueva generación que ha aumentado SLP y SG en CPRCm. MATERIAL Y MÉTODOS: Análisis retrospectivo de pacientes tratados con AA en nuestro centro (diciembre del 2012-septiembre del 2018). Analizamos la asociación del NLR (< o ≥ 3) previo y a los 6 meses de tratamiento con la respuesta del PSA, SLP y SG, y hormonosensibilidad previa a AA (< o > 12 meses). RESULTADOS: Hemos tratado a 56 pacientes con una mediana de edad de 82 (62-94), de los cuales 22 pacientes (39%) presentan NLR ≥ 3 previo al tratamiento. Existe una asociación estadísticamente significativa entre el NLR previo al tratamiento < 3 y la respuesta del PSA, OR = 9,444, p =0,001, no existiendo esa asociación con el NLR a los 6 meses de tratamiento. Se encontraron diferencias estadísticamente significativas entre los grupos de NLR < y > 3 previo al tratamiento con abiraterona en SLP con 15 meses de mediana vs.9 y una p = 0,008 y en SG con 20 meses vs.9 con una p = 0,014. Con respecto a la determinación de NLR, a los 6 meses no existen diferencias en las curvas de supervivencia entre ambos grupos. Existen diferencias significativas entre el NLR previo al tratamiento según la duración del tiempo hasta la resistencia a castración (p = 0,026). CONCLUSIONES: Nuestros resultados indican que el NLR podría aportarnos información trascendente y ser constituido un marcador pronóstico temprano y accesible en los pacientes con CPRCm en tratamiento en primera línea con abiraterona


INTRODUCTION: In patients with prostate cancer, high NLR seems to be associated with worse survival. Abiraterone acetate (AA) is a new generation hormonal treatment that has shown to increase PFS and OS in mCRPC. MATERIAL AND METHODS: Retrospective analysis of patients treated with AA in our center (December 2012-September 2018). We analyzed the association of the NLR (< or ≥ 3) before and after 6 months of treatment with PSA response, PFS, OS, and hormone sensitivity prior to AA (< or > 12 months). RESULTS: We have treated 56 patients with a median age of 82 (62-94), of which 22 (39%) had NLR ≥ 3 before treatment. There is a statistically significant association between the NLR prior to treatment < 3 and PSA response, OR = 9,444, P = .001, and there was no association with the NLR at 6 months of treatment. Statistically significant differences were found between the groups of NLR < and > 3 prior to treatment with abiraterone in PFS with 15 months of median vs.9 and P=.008, and in OS with 20 months vs.9 with P = .014. With respect to the determination of NLR at 6 months, there are no differences in the survival curves between both groups. There are significant differences between the NLR prior to treatment according to the length of hormone sensitivity (P = .026). CONCLUSIONS: Our results suggest that NLR could provide relevant information and could act as an early and accessible prognostic marker in patients with mCRPC in first line treatment with Abiraterone


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neutrófilos , Linfócitos , Acetato de Abiraterona/uso terapêutico , Antineoplásicos/uso terapêutico , Antígeno Prostático Específico/sangue , Intervalo Livre de Progressão , Estudos Retrospectivos , Biomarcadores Tumorais , Prognóstico
7.
Nutr Diabetes ; 4: e126, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-25027794

RESUMO

BACKGROUND: Contrasting with obesity, constitutional thinness (CT) is a rare condition of natural low bodyweight. CT exhibits preserved menstruation in females, no biological marker of undernutrition, no eating disorders but a bodyweight gain desire. Anorexigenic hormonal profile with high peptide tyrosine tyrosine (PYY) was shown in circadian profile. CT could be considered as the opposite of obesity, where some patients appear to resist diet-induced bodyweight loss. OBJECTIVE: The objective of this study was to evaluate appetite regulatory hormones in CTs in an inverse paradigm of diet-induced weight loss. METHODS: A 4-week fat overfeeding (2640 kJ excess) was performed to compare eight CT women (body mass index (BMI)<17.5 kg m(-)(2)) to eight female controls (BMI 18.5-25 kg m(-)(2)). Appetite regulatory hormones profile after test meal, food intake, bodyweight, body composition, energy expenditure and urine metabolomics profiles were monitored before and after overfeeding. RESULTS: After overfeeding, fasting total and acylated ghrelin were significantly lower in CTs than in controls (P=0.01 and 0.03, respectively). After overfeeding, peptide tyrosine tyrosine (PYY) and glucagon-like-peptide 1 both presented earlier (T15 min vs T30 min) and higher post-meal responses (incremental area under the curve) in CTs compared with controls. CTs failed to increase bodyweight (+0.22±0.18 kg, P=0.26 vs baseline), contrasting with controls (+0.72±0.26 kg, P=0.03 vs baseline, P=0.01 vs CTs). Resting energy expenditure increased in CTs only (P=0.031 vs baseline). After overfeeding, a significant negative difference between total energy expenditure and food intake was noticed in CTs only (-2754±720 kJ, P=0.01). CONCLUSION: CTs showed specific adaptation to fat overfeeding: overall increase in anorexigenic hormonal profile, enhanced post prandial GLP-1 and PYY and inverse to controls changes in urine metabolomics. Overfeeding revealed a paradoxical positive energy balance contemporary to a lack of bodyweight gain, suggesting yet unknown specific energy expenditure pathways in CTs.

8.
Mol Ecol Resour ; 12(6): 1151-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22823139

RESUMO

Progress in NGS technologies has opened up new opportunities for characterizing biodiversity, both for individual specimen identification and for environmental barcoding. Although the amount of data available to biologist is increasing, user-friendly tools to facilitate data analysis have yet to be developed. Our aim, with |SE|S|AM|E| Barcode, is to provide such support through a unified platform. The sequences are analysed through a pipeline that (i) processes NGS amplicon runs, filtering markers and samples, (ii) builds reference libraries and finally (iii) identifies (barcodes) the sequences in each amplicon from the reference library. We use a simulated data set for specimen identification and a recently published data set for environmental barcoding to validate the method. The results obtained are consistent with the expected characterizations (in silico and previously published, respectively). |SE|S|AM|E| Barcode and its documentation are freely available under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported Licence for Windows and Linux from http://www1.montpellier.inra.fr/CBGP/NGS/.


Assuntos
Bioestatística/métodos , Biologia Computacional/métodos , Código de Barras de DNA Taxonômico/métodos , Genômica/métodos , Software
9.
Insect Mol Biol ; 20(3): 399-408, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21435061

RESUMO

Honeybees have evolved a social immunity consisting of the cooperation of individuals to decrease disease in the hive. We identified a set of genes involved in this social immunity by analysing the brain transcriptome of highly varroa-hygienic bees, who efficiently detect and remove brood infected with the Varroa destructor mite. The function of these candidate genes does not seem to support a higher olfactory sensitivity in hygienic bees, as previously hypothesized. However, comparing their genomic profile with those from other behaviours suggests a link with brood care and the highly varroa-hygienic Africanized honeybees. These results represent a first step toward the identification of genes involved in social immunity and thus provide first insights into the evolution of social immunity.


Assuntos
Comunicação Animal , Abelhas/genética , Abelhas/imunologia , Comportamento Social , Varroidae , Animais , Abelhas/parasitologia , Encéfalo/metabolismo , Perfilação da Expressão Gênica
10.
Meat Sci ; 85(4): 788-91, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20416804

RESUMO

Québec consumers and pig farmers selected their preferred chop from 16 images that had been modified to give 16 treatments: two levels each of fat cover, colour, marbling and drip. The selection process was repeated eight times from different groups of chops. Fat cover (47% preferred lean) and colour (44%, light red) were the most frequently chosen characteristics. No significant differences were observed between farmers and consumers preferences (chi(2) test, P<0.05). Two preference-based clusters were found; 41% preferring dark red, lean meat and 59%, light red, lean meat, without marbling or drip. Choice-based clusters showed no significant links with either individual socio-demographic items, including pig farmer as occupation, or the three socio-demographic-based clusters observed (chi(2) test, P<0.05). No evidence was found to suggest that the choices of pig farmers differed from those of consumers and, therefore, inclusion of pig farmers in consumer panels would not bias consumer choice for pork.


Assuntos
Criação de Animais Domésticos , Composição Corporal , Comportamento do Consumidor , Preferências Alimentares , Carne , Projetos de Pesquisa/normas , Adolescente , Adulto , Animais , Recursos Audiovisuais , Distribuição de Qui-Quadrado , Análise por Conglomerados , Cor , Emprego , Gorduras , Feminino , Tecnologia de Alimentos , Humanos , Masculino , Quebeque , Fatores Socioeconômicos , Suínos , Adulto Jovem
11.
J Oral Rehabil ; 34(4): 251-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17371562

RESUMO

The aim of the present study was to underline the difference in premolar-molar functional areas according to both age and gender in a human adult population. Premolar and molar series were marked manually on opposed casts with articulating paper and functional areas were evaluated by quantification of these markings. It was noticed that on average larger functional areas were displayed by the older group (19 individuals, mean age 71.2 years, minimum 68 years, maximum 73 years) in comparison with the younger one (24 individuals, mean age 27.4 years, minimum 22 years; maximum 33 years). It was also observed that the average total functional area (4 hemiarches) was larger in the male subgroup (n: 23; mean age 45; young adults, 14; old adults, 9) compared with the female one (n: 20; mean age 49; young adults, 10; old adults, 10). Nevertheless, this gender difference in premolar-molar functional areas was related to the individual occlusal areas. As a matter of fact, when the individual occlusal area was taken into account for each series in the form of a ratio (functional area/occlusal area), the values obtained were not different between both gender subgroups studied. When comparing premolar and molar functional ratios (functional area/occlusal area) between age groups, it appears that the values obtained were slightly higher for the premolar series (ratios for young and older adults, respectively: Premolar series: 23.6+/-7.5%, 30+/-6.5%; Molar series: 23.1+/-6.8%, 27.3+/-6.7%). This difference was interpreted in relation to the reference (occlusal area) chosen.


Assuntos
Dente Pré-Molar/fisiologia , Dente Molar/fisiologia , Adulto , Fatores Etários , Idoso , Técnica de Moldagem Odontológica , Oclusão Dentária , Feminino , Humanos , Masculino , Fatores Sexuais
12.
Mol Phylogenet Evol ; 42(3): 598-611, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17113793

RESUMO

Aphis is the largest aphid genus in the world and contains several of the most injurious aphid pests. It is also the most reluctant aphid genus to any comprehensive taxonomic treatment: while most species are easily classified into "species groups" that form well defined entities, numerous species within these groups are difficult to tell apart morphologically and identification keys remain ambiguous and mostly rely on host plant affiliation. In this paper, we used partial sequences of COI/COII and CytB genes to reconstruct the first phylogeny of Aphis and discuss the present systematics. The monophyly of the subgenus Bursaphis and of the tree major species groups, Black aphid, Black backed aphid and frangulae-like species was recovered by all phylogenetic analyses. However our data suggested that the nominal subgenus was not monophyletic. Relationships between major species groups were often ambiguous but "Black" and "Black backed" species groups appeared as sister clades. The most striking result of this study was that our molecular data met the same limits as the morphological characters used in classifications: mitochondrial DNA did not allow the differentiation of species that are difficult to identify. Further, interspecies relationships within groups of species for which taxonomic treatment is difficult stayed unresolved. This suggests that species delineation in the genus Aphis is often ambiguous and that diversification might have been a rapid process.


Assuntos
Afídeos/genética , DNA Mitocondrial/análise , Filogenia , Análise de Sequência de DNA , Animais , Citocromos b/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Modelos Biológicos
13.
J Biotechnol ; 119(1): 15-9, 2005 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-15961176

RESUMO

The development of non-invasive molecular techniques is currently increasing, particularly in the fields of behavioural ecology and conservation genetics of mammals. Surprisingly, genetic studies of Arthropods and particularly the insects have not benefited yet from the contributions that non-invasive methods have made. Here, we outline a strategy for identifying phytophagous insect genetic entities based on direct-PCR of fecal DNA combined with double strand conformation polymorphism (DSCP) typing. This allows the differentiation of morphocryptic entities within the species Ceutorhynchus assimilis (Coleoptera: Curculionidae), a candidate biocontrol agent of a noxious weed. The results obtained clearly demonstrate the potential for this method to provide a valuable means for genetic and ecological studies of Arthropods.


Assuntos
DNA/análise , Genética Populacional , Reação em Cadeia da Polimerase/métodos , Gorgulhos/genética , Animais , Sequência de Bases , DNA/genética , Fezes , Dados de Sequência Molecular , Polimorfismo Genético
14.
Meat Sci ; 66(1): 125-34, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22063940

RESUMO

Consumer focus groups in France, England, Sweden and Denmark were used to obtain insights into the decision-making involved in the choice of fresh pork and attitudes towards today's pig production systems. Many positive perceptions of pork meat were evoked. Negative images of the production systems in use today were expressed, but rationalised in terms of consumer demands, market competition and by comparisons to previous systems of production. Knowledge of production systems appeared of little consequence in terms of any meat market potential as several groups freely remarked that there was no link between the negative images of production methods and their purchase behaviour. The groups were clearly confused and mistrusted the limited information available at the point of purchase. Careful consideration should be given to meat labelling, in particular taking account of the evident consumer ethnocentrism, to assure that such information is targeted to enhance consumer confidence.

15.
Mol Ecol ; 12(5): 1265-75, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12694289

RESUMO

Natural genetic variants at the phosphoglucose isomerase, PGI, gene differ in spatial patterning of their polymorphism among species complexes of Colias butterflies in North America. In both lowland and alpine complexes, molecular-functional properties of the polymorphic genotypes can be used to predict genotype-specific adult flight performances and resulting large genotypic differences in adult fitness components. In the lowland species complex, there is striking uniformity of PGI polymorph frequencies at a number of sites across the American West; this fits with earlier findings of strong, similar differences in fitness components over this range. In an alpine complex, Colias meadii shows similar uniformity of PGI frequencies within habitat types, either montane steppe or alpine tundra, over several hundred kilometres in the absence of dispersal. At the same time, large shifts (10-20%) in frequency of the most common alleles occur between steppe and tundra populations, whether these are isolated or, as in some cases, are in contact and exchange many dispersing adults each generation. Data on male mating success of common C. meadii PGI genotypes in steppe and tundra show heterozygote advantage in both habitat types, with shifts in relative homozygote disadvantage between habitats which are consistent with observed frequency differences. Nonadaptive explanations for this situation are rejected, and alternative, thermal-ecology-based adaptive hypotheses are proposed for later experimental test. These findings show that strong local selection may dominate dispersal as an evolutionary agent, whether or not dispersal is present, and that selection may often be the major force promoting 'cohesion' of species over long distances. This case offers new opportunities for integrating studies of molecular structure and function with ecological aspects of natural selection in the wild, both within and among species.


Assuntos
Adaptação Biológica/genética , Borboletas/genética , Borboletas/fisiologia , Variação Genética/fisiologia , Glucose-6-Fosfato Isomerase/genética , Seleção Genética , Animais , Eletroforese em Gel de Poliacrilamida , Meio Ambiente , Voo Animal/fisiologia , Frequência do Gene , América do Norte , Dinâmica Populacional
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