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1.
Genet Mol Res ; 13(1): 167-81, 2014 Jan 10.
Article de Anglais | MEDLINE | ID: mdl-24446300

RÉSUMÉ

Movement is an important life history trait that can have an impact on local adaptation, and other evolutionary phenomena. We used a combination of nestbox survey data and genetic techniques (genotyping at 10 microsatellite loci) to quantify patterns of movement in common dormice Muscardinus avellanarius at two distinct sites in the UK: 1) Bontuchel (a natural population) and 2) Wych (captive-bred individuals that were reintroduced to this site), over three consecutive years (2006-2008). Both methods revealed a consistent pattern of sex-biased movement (movements by adult males and females) in both populations that allowed isolation-by-distance genetic structure to develop within 1 km. The similarity of data from captive-bred and natural individuals indicated that ex situ programing has not significantly altered the natural movement behavior of common dormice; consequently, the two populations could be managed with the same conservation strategies. We also found that the reintroduced dormice in Wych maintained relatively high levels of genetic diversity. This first report of movement patterns in reintroduced and natural populations of M. avellanarius combining genetic and field-survey data highlights the role of genetic studies in the investigation of ecological behaviour and for conservation management.


Sujet(s)
Variation génétique , Mouvement , Myoxidae/génétique , Adaptation physiologique , Animaux , Femelle , Mâle , Répétitions microsatellites , Myoxidae/physiologie , Isolement reproductif , Facteurs sexuels
2.
Parasitology ; 135(5): 567-74, 2008 Apr.
Article de Anglais | MEDLINE | ID: mdl-18371241

RÉSUMÉ

A panel of microsatellites mapped to the Leishmania genome might make it possible to find associations between specific loci and phenotypic traits. To identify such loci, a Perl programme was written that scans the sequence of a genome and writes all loci containing microsatellites to a MySQL database. The programme was applied to the sequences of the L. braziliensis, L. infantum and L. major genomes. The database is publicly available over the internet: http://www.genomics.liv.ac.uk/tryps/resources.html 'Microsatellite Locus Extractor', and allows the selection of mapped microsatellites that meet user-defined criteria from a specified region of the selected genome. The website also incorporates a primer design pipeline that will design primers to amplify the selected loci. Using this pipeline 12 out of 17 primer sets designed against the L. infantum genome generated polymorphic PCR products. A tailed primer protocol was used to label all microsatellite primers with a single set of labelled primers. To avoid the culture of parasites prior to genotyping, sets of nested PCR primers were developed to amplify parasite DNA eluted from microscope slides. The limit of detection was approximately 1.6 parasite equivalents. However, only 6/56 DNA from slides stored at ambient temperature for over 6 months gave positive PCR results.


Sujet(s)
Leishmania brasiliensis , Leishmania donovani , Leishmania major , Répétitions microsatellites/génétique , Parasitologie/méthodes , Animaux , Biologie informatique/méthodes , Amorces ADN , ADN des protozoaires/analyse , Humains , Iran , Leishmania brasiliensis/classification , Leishmania brasiliensis/génétique , Leishmania donovani/classification , Leishmania donovani/génétique , Leishmania major/classification , Leishmania major/génétique , Leishmaniose cutanée/parasitologie , Leishmaniose viscérale/parasitologie , Réaction de polymérisation en chaîne , Sensibilité et spécificité
3.
Mol Ecol ; 12(7): 1879-94, 2003 Jul.
Article de Anglais | MEDLINE | ID: mdl-12803639

RÉSUMÉ

Lutzomyia longipalpis, the main sandfly vector for New World visceral leishmaniasis is a complex of an as yet undefined number of sibling species. At present, there is no consensus on the status (single species vs. species complex) of Brazilian populations. We applied five microsatellite loci to test the hypothesis that L. longipalpis occurs as two sympatric cryptic species in Sobral, Ceará State, Brazil as predicted by male sex pheromone chemotypes described previously for field specimens from this site [S-9-methyl-germacrene-B (9MGB) and a cembrene compound]. Abdominal spot morphology corresponds with pheromone type at this locality (9MGB in '1 spot' males and cembrene in '2 spot' males). Genotype data from 190 wild-caught L. longipalpis specimens collected in October 1999 and April 2001 were used to estimate genetic differentiation between the two sex pheromone populations and sampling dates. No significant (P > 0.05) genetic differences were found between the 1999 and 2001 9MGB samples (theta = 0.018; RST = -0.005), and genetic differentiation was low between the cembrene collections (theta = 0.037, P < 0.05; RST = -0.043, P > 0.05). By contrast, highly divergent allelic frequencies (largely at two microsatellite loci) corresponded to significant (P > 0.05) genetic differentiation (theta = 0.221; RST = 0.215) for all comparisons between samples with different pheromones. When pheromone samples were pooled across sample date, genetic differentiation was high (theta = 0.229; P < 0.001; Nem = 0.84). The allele frequency distribution at each of the five microsatellite loci was similar for males and females from the two collection years. Two of these loci showed highly divergent allele frequencies in the two sex pheromone populations. This was reflected in the highly significant genetic differentiation obtained from the male genotypes, between populations producing different pheromones (theta = 0.229-0.268; P < 0.0001 for the 2001 and theta = 0.254-0.558; P < 0.0001 for the 1999 collections, respectively). Similar results were obtained when the females, assigned to a pheromone type, were included in the analysis. Both a Bayesian analysis of the data set and a population assignment test provided strong evidence for two distinct populations corresponding to pheromone type. Given its genotype, the probability of assigning a 9MGB male to the original 9MGB population was 100% once the two years' collections were pooled. For cembrene-producing '2 spot' males this probability although still high, was lower than for 9MGB males, at 86%. This microsatellite data together with previously reported reproductive isolation between the two Sobral populations confirm that premating barriers are important in speciation of L. longipalpis.


Sujet(s)
Évolution moléculaire , Variation génétique , Génétique des populations , Psychodidae/génétique , Phéromones sexuelles/génétique , Animaux , Théorème de Bayes , Brésil , Analyse de regroupements , Fréquence d'allèle , Mâle , Répétitions microsatellites/génétique , Polymorphisme de restriction , Reproduction/génétique , Spécificité d'espèce
4.
Rev Elev Med Vet Pays Trop ; 46(1-2): 283-90, 1993.
Article de Anglais | MEDLINE | ID: mdl-8134643

RÉSUMÉ

By using biological data and historical research, we have tried to explain the difference between resistance and susceptibility to the diseases transmitted (cowdriosis) or associated (dermatophilosis) with the tick Amblyomma variegatum, in two cattle breeds of the French West Indies: the Creole crossbred cattle of Guadeloupe and the Brahman zebu cattle of Martinique. Have been studied the polymorphisms of 5 independent genetic systems (erythrocytic haemoglobin, serum albumin and transferrin, the class I region of the BoLA complex and the gamma S crystallin gene) in different breeds comprising Bos taurus cattle of Europe and Africa, Bos indicus of West and East Africa, as well as the Brahman of Martinique and the Creole crossbred of Guadeloupe. By comparing the different allele frequencies of these 5 non related polymorphic loci and by using the two different mathematical matrices of NEI and of CAVALLI-SFORZA, have been established the genetic distances between these breeds. It appears clearly that the Creole cattle of Guadeloupe are in an intermediate position between the Bos taurus N'Dama breed of West Africa and two Bos indicus zebu breeds, namely the West African Sudan zebu and the Brahman. Thanks to studies of different archieves in the Caribbean and in Europe, historical evidence have been accumulated on the geographical origins and on the chronology of the establishment of Creole and Brahman cattle in the French West Indies. The high resistance of the Creole cattle of Guadeloupe to diseases associated with or transmitted by the "Senegalese" tick Amblyomma variegatum seems to be due to the inheritance of a pool of genes from West African cattle and more particularly from the N'Dama breed.(ABSTRACT TRUNCATED AT 250 WORDS)


Sujet(s)
Maladies des bovins/génétique , Bovins/génétique , Infestations par les tiques/médecine vétérinaire , Animaux , Sélection , Maladies des bovins/histoire , Histoire du 16ème siècle , Histoire du 17ème siècle , Histoire du 18ème siècle , Histoire du 19ème siècle , Histoire du 20ème siècle , Polymorphisme génétique , Antilles
5.
Brain Lang ; 42(1): 89-102, 1992 Jan.
Article de Anglais | MEDLINE | ID: mdl-1547471

RÉSUMÉ

This longitudinal study describes the growth of syntactic abilities and vocabulary size in nine children with unilateral antepartum or perinatal brain injury. Five children with left hemisphere damage (LHD) and four with right hemisphere damage (RHD), ages 15 to 48 months, were evaluated on three or more occasions. Language samples generated from parent-child interaction were transcribed, coded, and analyzed using the Child Language Data Exchange System. Individual growth trajectories were constructed by graphing three dependent variables--MLU, scores on the Index of Productive Syntax (IPSYN), and number of different words--as a function of the child's age. One subject remained in a prelinguistic stage throughout the study. Simple linear functions best described the growth of MLU, IPSYN scores, and vocabulary in the other eight children. The slopes of the individual growth trajectories, the graphic representations of rates of progress, were comparable in the eight children. Seven children showed developmental delays in initial word use and five in the onset of multiword utterances. However, by age 24 months, four children with LHD and two children with RHD had syntactic capabilities comparable to those of children without brain injuries. The developmental patterns suggested that both cerebral hemispheres may play critical roles in the very earliest stages of language acquisition. Some unilateral lesions caused little discernible effect on language outcome in the toddler-preschool years after the initial developmental delays.


Sujet(s)
Souffrance cérébrale chronique/congénital , Dominance cérébrale/physiologie , Troubles du développement du langage/diagnostic , Souffrance cérébrale chronique/complications , Enfant d'âge préscolaire , Femelle , Humains , Tests du langage , Mâle , Examen neurologique , Apprentissage verbal/physiologie , Vocabulaire
9.
J Pediatr ; 105(3): 394-8, 1984 Sep.
Article de Anglais | MEDLINE | ID: mdl-6470861

RÉSUMÉ

Serum was collected from children with type 1 diabetes mellitus before and 10 days after attending a camp session in which blood glucose concentrations were carefully controlled. Glycosylated and nonglycosylated proteins were separated, and levels of albumin and transferrin were determined on each of these fractions. Glycosylated hemoglobin was also determined and ranged from 4.6% to 14.6% (mean +/- SEM 8.1% +/- 0.2%). Mean initial glycosylated albumin in 73 children was 16.4% +/- 0.6%, which was elevated compared with the mean of levels in 20 nondiabetic controls (8.7% +/- 0.3%) and correlated well with levels of glycosylated hemoglobin (r = 0.71). After 10 days mean glycosylated albumin fell to 14.6% +/- 0.5% (P less than 0.00001), near the predicted final value of 13.4% if control had been ideal. Initial levels of glycosylated transferrin in 44 of these children ranged from 4.5% to 22.3% (11.4 +/- 0.6%) and was significantly higher than the mean of 3.8% +/- 0.3% in 20 nondiabetic controls. Mean final glycosylated transferrin fell to 8.2% +/- 0.3% (P less than 0.00001), near the predicted final mean of 7.0% +/- 0.2%. The mean of each subject's blood glucose determinations performed throughout the study period correlated with final levels of both glycosylated albumin (r = 0.55, P less than 0.001) and glycosylated transferrin (r = 0.54, P less than 0.001). Both glycosylated albumin and glycosylated transferrin appear to be reliable markers of short-term glycemic control; glycosylated transferrin (half-life 8 days) was more sensitive than glycosylated albumin over this 10-day period.


Sujet(s)
Hyperglycémie/sang , Sérumalbumine/analyse , Transferrine/analyse , Adolescent , Adulte , Enfant , Hémoglobine glyquée/analyse , Humains , Sérumalbumine/métabolisme , Transferrine/métabolisme
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