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1.
Rev. bras. reprod. anim ; 46(2): 130-134, Abril-Junho 2022.
Article de Portugais | VETINDEX | ID: biblio-1378095

RÉSUMÉ

As tecnologias de reprodução assistida (TRA) são de fundamental importância para a conexão de indivíduos em diferentes localidades, facilitando assim o intercâmbio genético e favorecendo a variabilidade genética de uma espécie. Por esta razão, as TRAS podem ser ferramentas importantes para a conservação de espécies ameaçadas de extinção. Apesar dos esforços nas últimas décadas, o avanço no desenvolvimento de tais tecnologias está aquém à urgência de reverter processos de baixa variabilidade genética em algumas espécies. A necessidade de refinamento das técnicas para as particularidades fisiológicas e comportamentais de cada espécie, somada à raridade de acesso aos animais são os principais fatores relacionados as dificuldades em se avançar com as TRAS. As técnicas mais recentes desenvolvidas para a recuperação de espermatozoides em animais selvagens são a colheita farmacológica, com uso de alfa-2-agonistas e a criopreservação / vitrificação testicular com posterior cultivo. Pouco de avançou, no entanto, em relação aos métodos de criopreservação, prevalecendo associação clássica de TRIS-gema-glicerol. Discutimos, então os métodos usados para acesso ao gameta masculino em espécies selvagens e suas aplicações na conservação animal.(AU)


Assisted reproduction technologies (ART) are of fundamental importance for connecting individuals in different locations, thus facilitating genetic exchange and favoring the genetic variability of a species. For this reason, TRAS can be important tools for the conservation of endangered species. Despite efforts in recent decades, the advance in the development of such technologies is short of the urgency of reversing processes of low genetic variability in some species. The need to refine the techniques for the physiological and behavioral particularities of each species, added to the rarity of access to animals, are the main factors related to the difficulties in advancing with TRAS. The most recent techniques developed for sperm collection in wild animals are pharmacological collection, with the use of alpha-2-agonists and testicular cryopreservation / vitrification with subsequent cultivation. Little progress has been made, however, in relation to cryopreservation methods, prevailing the classic association of TRIS-yolk-glycerol. We therefore discuss the methods used to access the male gamete in wild species and their applications in animal conservation.(AU)


Sujet(s)
Animaux , Mâle , Techniques de reproduction assistée/médecine vétérinaire , Cellules germinales/cytologie , Animaux sauvages/physiologie , Variation génétique/physiologie , Cryoconservation/méthodes , Prélèvement de sperme/médecine vétérinaire , Analyse du sperme/méthodes , Agonistes des récepteurs alpha-2 adrénergiques/composition chimique , Vitrification
2.
Acta amaz ; 52(2): 80-95, 2022. tab, graf
Article de Anglais | VETINDEX | ID: biblio-1378453

RÉSUMÉ

Amazon chicory is still a little-known vegetable despite its great agronomic potential. The characterization of chicory genotypes concerning genetic divergence is a key step for breeding programs, as it allows the selection of superior individuals and to explore the variability and complementarity of characteristics via interbreeding between newly generated genotypes. In this context, this study aimed to evaluate the genetic divergence among Amazon chicory creole genotypes from the northern Brazilian states of Pará and Rondônia based on morpho-agronomic traits. We conducted an experiment in a randomized block design with eight chicory genotypes (treatments) and four replications. Both quantitative and qualitative characteristics were evaluated. Genetic divergence was estimated via squared generalized Mahalanobis distance (D2 ), considering only quantitative characters, and the genotypes were subsequently clustered via the UPGMA method. Analysis of variance showed significant differences among genotypes for all studied characteristics, except shoot fresh weight. The UPGMA grouped the genotypes into three clusters, which demonstrated that the genotypes from Colares and Santarém Novo (Pará) (Chic-02 and Chic-04) were the most divergent as compared to the genotypes from Castanhal and Santa Isabel do Pará (Pará). Qualitative characteristics showed a monomorphic behavior and, therefore, were not used to assess genetic divergences. To obtain segregating populations with complementary characteristics, crossbreeding between the two most divergent clusters is recommended.(AU)


A chicória da Amazônia é uma hortaliça ainda pouco conhecida, mas com grande potencial agronômico. A caracterização dos genótipos de chicória quanto a divergência genética é um importante passo para programas de melhoramento genético, pois permite selecionar indivíduos superiores e explorar a variabilidade e a complementariedade de características, a partir dos novos genótipos gerados. Nesse contexto, o objetivo deste estudo foi avaliar a divergência genética de genótipos crioulos de chicória da Amazônia dos estados do Pará e Rondônia, com base em caracteres morfoagronômicos. Realizou-se um experimento em delineamento de blocos ao acaso, com oito genótipos de chicória (tratamentos) e quatro repetições. Foram avaliadas características quantitativas e qualitativas. A divergência genética foi estimada a partir da distância quadrada generalizada de Mahalanobis (D2 ), levando em consideração apenas os caracteres quantitativos, e os genótipos foram agrupados pelo método UPGMA. A análise de variância evidenciou diferença significativa entre os genótipos para todas as características, exceto massa fresca. O UPGMA agrupou os genótipos em três grupos, sendo os genótipos de Colares e Santarém Novo (Pará) (Chic-02 e Chic-04) os mais divergentes em comparação com os genótipos da região de Castanhal e Santa Isabel do Pará (Pará). As características qualitativas apresentaram padrão monomórfico, não sendo, portanto, utilizadas para avaliar a divergência. Para obter populações segregantes com complementariedade de características, recomenda-se o cruzamento entre os dois grupos mais divergentes.(AU)


Sujet(s)
Variation génétique/physiologie , Eryngium/génétique , Brésil , Amélioration des plantes/statistiques et données numériques
3.
PLoS One ; 16(8): e0256457, 2021.
Article de Anglais | MEDLINE | ID: mdl-34449804

RÉSUMÉ

The aim of our study was to assess the importance of different Colombian bioregions in terms of the supply of useful plant species and the quality of the available distribution data. We assembled a dataset of georeferenced collection localities of all vascular plants of Colombia available from global and local online databases. We then assembled a list of species, subspecies and varieties of Colombia's useful plants and retrieved all point locality information associated with these taxa. We overlaid both datasets with a map of Colombia's bioregions to retrieve all species and useful species distribution records in each bioregion. To assess the reliability of our estimates of species numbers, we identified information gaps, in geographic and environmental space, by estimating their completeness and coverage. Our results confirmed that Colombia's third largest bioregion, the Andean moist forest followed by the Amazon, Pacific, Llanos and Caribbean moist forests contained the largest numbers of useful plant species. Medicinal use was the most common useful attribute across all bioregions, followed by Materials, Environmental uses, and Human Food. In all bioregions, except for the Andean páramo, the proportion of well-surveyed 10×10 km grid cells (with ≥ 25 observation records of useful plants) was below 50% of the total number of surveyed cells. Poor survey coverage was observed in the three dry bioregions: Caribbean deserts and xeric shrublands, and Llanos and Caribbean dry forests. This suggests that additional primary data is needed. We document knowledge gaps that will hinder the incorporation of useful plants into Colombia's stated plans for a bioeconomy and their sustainable management. In particular, future research should focus on the generation of additional primary data on the distribution of useful plants in the Amazon and Llanos (Orinoquia) regions where both survey completeness and coverage appeared to be less adequate compared with other regions.


Sujet(s)
Forêts , Variation génétique/génétique , Plantes médicinales/physiologie , Plantes/classification , Caraïbe , Colombie , Variation génétique/physiologie , Humains , Plantes/génétique , Plantes médicinales/classification
4.
Commun Biol ; 4(1): 160, 2021 02 05.
Article de Anglais | MEDLINE | ID: mdl-33547394

RÉSUMÉ

Extant conifer species may be susceptible to rapid environmental change owing to their long generation times, but could also be resilient due to high levels of standing genetic diversity. Hybridisation between closely related species can increase genetic diversity and generate novel allelic combinations capable of fuelling adaptive evolution. Our study unravelled the genetic architecture of adaptive evolution in a conifer hybrid zone formed between Pinus strobiformis and P. flexilis. Using a multifaceted approach emphasising the spatial and environmental patterns of linkage disequilibrium and ancestry enrichment, we identified recently introgressed and background genetic variants to be driving adaptive evolution along different environmental gradients. Specifically, recently introgressed variants from P. flexilis were favoured along freeze-related environmental gradients, while background variants were favoured along water availability-related gradients. We posit that such mosaics of allelic variants within conifer hybrid zones will confer upon them greater resilience to ongoing and future environmental change and can be a key resource for conservation efforts.


Sujet(s)
Adaptation biologique/génétique , Introgression génétique/physiologie , Spéciation génétique , Tracheobionta/génétique , Allèles , Arizona , Évolution biologique , Variation génétique/physiologie , Géographie , Hybridation génétique/physiologie , Mexique , Mosaïcisme , Pinus/génétique , Polymorphisme de nucléotide simple , Tracheobionta/classification
5.
J Alzheimers Dis ; 77(2): 877-883, 2020.
Article de Anglais | MEDLINE | ID: mdl-32741827

RÉSUMÉ

BACKGROUND: A major drawback in Alzheimer's disease (AD) is the lack of validated biomarkers for routine clinical diagnostic. We have reported earlier a novel blood biomarker, named Alz-tau®, based on variants of platelet tau. This marker evaluates the ratio of high molecular weight tau (HMWtau) and the low molecular weight (LMWtau) tau. OBJECTIVE: To analyze a potential novel source of antigen for Alz-tau®, plasma tau, detected by immunoreactivity with the novel monoclonal antibody, tau51. METHODS: We evaluated tau variants in plasma precipitated with ammonium sulfate from 36 AD patients and 15 control subjects by western blot with this novel monoclonal antibody. RESULTS: The HMW/LMWtau ratio was statistically different between AD patients and controls. CONCLUSIONS: Plasma tau variants are suitable to be considered as a novel antigen source for the Alz-tau® biomarker for AD.


Sujet(s)
Maladie d'Alzheimer/sang , Maladie d'Alzheimer/diagnostic , Anticorps monoclonaux/sang , Variation génétique/physiologie , Protéines tau/sang , Sujet âgé , Sujet âgé de 80 ans ou plus , Maladie d'Alzheimer/génétique , Anticorps monoclonaux/génétique , Marqueurs biologiques/sang , Femelle , Humains , Mâle , Adulte d'âge moyen , Protéines tau/génétique
6.
Sci Rep ; 9(1): 19482, 2019 12 20.
Article de Anglais | MEDLINE | ID: mdl-31862901

RÉSUMÉ

In roots of Arabidopsis thaliana, Zn can be either loaded into the xylem for translocation to the shoot or stored in vacuoles. Vacuolar storage is achieved through the action of the Zn/Cd transporter HMA3 (Heavy Metal Atpase 3). The Col-0 accession has an HMA3 loss-of-function allele resulting in high shoot Cd, when compared to accession CSHL-5 which has a functional allele and low shoot Cd. Interestingly, both Col-0 and CSHL-5 have similar shoot Zn concentrations. We hypothesize that plants sense changes in cytosolic Zn that are due to variation in HMA3 function, and respond by altering expression of genes related to Zn uptake, transport and compartmentalisation, in order to maintain Zn homeostasis. The expression level of genes known to be involved in Zn homeostasis were quantified in both wild-type Col-0 and Col-0::HMA3CSHL-5 plants transformed with the functional CSHL-5 allele of HMA3. We observed significant positive correlations between expression of HMA3 and of genes known to be involved in Zn homeostasis, including ZIP3, ZIP4, MTP1, and bZIP19. The results support our hypothesis that alteration in the level of function of HMA3 is counterbalanced by the fine regulation of the Zn homeostasis gene network in roots of A. thaliana.


Sujet(s)
Protéines d'Arabidopsis/métabolisme , Arabidopsis/métabolisme , Arabidopsis/génétique , Protéines d'Arabidopsis/génétique , Régulation de l'expression des gènes végétaux/génétique , Régulation de l'expression des gènes végétaux/physiologie , Variation génétique/génétique , Variation génétique/physiologie , Zinc/métabolisme
7.
Sci Rep ; 9(1): 17383, 2019 11 22.
Article de Anglais | MEDLINE | ID: mdl-31758041

RÉSUMÉ

The alarming rate of global pollinator decline has made habitat restoration for pollinators a conservation priority. At the same time, empirical and theoretical studies on plant-pollinator networks have demonstrated that plant species are not equally important for pollinator community persistence and restoration. However, the scarcity of comprehensive datasets on plant-pollinator networks in tropical ecosystems constrains their practical value for pollinator restoration. As closely-related species often share traits that determine ecological interactions, phylogenetic relationships could inform restoration programs in data-scarce regions. Here, we use quantitative bee-plant networks from Brazilian ecosystems to test if priority plant species for different restoration criteria (bee species richness and visitation rates) can be identified using interaction networks; if phylogenetic relationships alone can guide plant species selection; and how restoration criteria influence restored network properties and function. We found plant species that maximised the benefits of habitat restoration for bees (i.e., generalists and those with distinct flower-visitor species) were clustered in a small number of phylogenetically-diverse plant families, and that prioritising the recovery of bee visitation rates improved both stability and function of restored plant-pollinator networks. Our approach can help guide restoration of pollinator communities, even where information on local ecosystems is limited.


Sujet(s)
Écosystème , Assainissement et restauration de l'environnement/méthodes , Variation génétique/physiologie , Plantes/classification , Plantes/génétique , Pollinisation/physiologie , Animaux , Abeilles/physiologie , Brésil , Fleurs/classification , Fleurs/génétique , Phénotype , Phylogenèse , Densité de population
8.
Gac. méd. Méx ; Gac. méd. Méx;155(5): 463-470, Sep.-Oct. 2019. tab, graf
Article de Anglais | LILACS | ID: biblio-1286544

RÉSUMÉ

The first draft of the human genome sequencing published in 2001 reported a large number of single nucleotide polymorphisms (SNPs). Given that these polymorphisms could practically represent all the variability involved in the susceptibility, protection, severity, among other aspects, of various common diseases, as well as in their response to medications, it was thought that they might be “the biomarkers of choice” in personalized genomic medicine. With the new information obtained from the sequencing of a larger number of genomes, we have understood that SNPs are only an important part of the genetic markers involved in these traits. In addition to SNPs, other variants have been identified, such as insertions/deletions (INDELs) and copy number variants (CNVs), which – in addition to classic variable number tandem repeats (VNTRs) and short tandem repeats (STRs) – originate or contribute to the development of diseases. The use of these markers has served to identify regions of the genome involved in Mendelian diseases (one gene-one disease) or genes directly associated with multifactorial diseases. This review has the purpose to describe the role of STRs, VNTRs, SNPs, CNVs and INDELs in linkage and association studies and their role in Mendelian and multifactorial diseases.


Sujet(s)
Humains , Variation génétique/physiologie , Maladie/génétique , Polymorphisme de nucléotide simple , Marqueurs génétiques , Génome humain , Mutagenèse par insertion , Délétion de gène , Séquences répétées en tandem , Lod score , Mutation
10.
Gac Med Mex ; 155(5): 463-470, 2019.
Article de Anglais | MEDLINE | ID: mdl-32091015

RÉSUMÉ

The first draft of the human genome sequencing published in 2001 reported a large number of single nucleotide polymorphisms (SNPs). Given that these polymorphisms could practically represent all the variability involved in the susceptibility, protection, severity, among other aspects, of various common diseases, as well as in their response to medications, it was thought that they might be "the biomarkers of choice" in personalized genomic medicine. With the new information obtained from the sequencing of a larger number of genomes, we have understood that SNPs are only an important part of the genetic markers involved in these traits. In addition to SNPs, other variants have been identified, such as insertions/deletions (INDELs) and copy number variants (CNVs), which - in addition to classic variable number tandem repeats (VNTRs) and short tandem repeats (STRs) - originate or contribute to the development of diseases. The use of these markers has served to identify regions of the genome involved in Mendelian diseases (one gene-one disease) or genes directly associated with multifactorial diseases. This review has the purpose to describe the role of STRs, VNTRs, SNPs, CNVs and INDELs in linkage and association studies and their role in Mendelian and multifactorial diseases.


Sujet(s)
Maladie/génétique , Variation génétique/physiologie , Polymorphisme de nucléotide simple , Délétion de gène , Marqueurs génétiques , Génome humain , Humains , Lod score , Mutagenèse par insertion , Mutation , Séquences répétées en tandem
11.
PLoS One ; 13(8): e0201251, 2018.
Article de Anglais | MEDLINE | ID: mdl-30089137

RÉSUMÉ

We investigated the molecular phylogenetic divergence and historical biogeography of the gall-inducing micromoth Eucecidoses minutanus Brèthes (Cecidosidae) in the Neotropical region, which inhabits a wide range and has a particular life history associated with Schinus L. (Anacardiaceae). We characterize patterns of genetic variation based on 2.7 kb of mitochondrial DNA sequences in populations from the Parana Forest, Araucaria Forest, Pampean, Chacoan and Monte provinces. We found that the distribution pattern coincides with the Peripampasic orogenic arc, with most populations occurring in the mountainous areas located east of the Andes and on the Atlantic coast. The phylogeny revealed a marked geographically structured differentiation, which highlights a first split into two major clades: western (Monte and Chacoan) and eastern (Pampean and coastal forests). Together with AMOVA and network analysis, phylogeny revealed the existence of six well-defined lineages, which are isolated by distance. The TMRCA for Eucecidoses was estimated at ca. 65 Mya, and the divergence among major clades occurred by the Plio-Pleistocene ca. 20-25 Mya, with the extant six lineages emerging about 0.9 to 5.7 Mya (later than the rise of Schinus). These results are associated with a diversification pattern of either a late burst of speciation or early extinction. Population range expansion for some lineages concurring with major climatic changes that occurred during the wet-dry events of the Pleistocene in the region was recovered in both neutrality tests and past dynamics through time analysis. A possible biogeographic scenario reconstructed suggests that Eucecidoses likely emerged from a central meta-population in the south and later dispersed (ca. 38 Mya) using western and eastern as two major routes. Thus, a combination of dispersal and vicariance events that occurred in the ancestral populations might have shaped the current distribution of extant lineages. Speciation driven by host plant shift is potentially involved in the evolutionary history of Eucecidoses.


Sujet(s)
Variation génétique/physiologie , Papillons de nuit/physiologie , Phylogenèse , Animaux , Phylogéographie , Dynamique des populations , Amérique du Sud
12.
PLoS One ; 13(7): e0200796, 2018.
Article de Anglais | MEDLINE | ID: mdl-30020992

RÉSUMÉ

The human genetic diversity around the world was studied through several high variable genetic markers. In South America the demic consequences of admixture events between Native people, European colonists and African slaves have been displayed by uniparental markers variability. The mitochondrial DNA (mtDNA) has been the most widely used genetic marker for studying American mixed populations, although nuclear markers, such as microsatellite loci (STRs) commonly used in forensic science, showed to be genetically and geographically structured. In this work, we analyzed DNA from buccal swab samples of 296 individuals across Peru: 156 Native Amazons (Ashaninka, Cashibo and Shipibo from Ucayali, Huambiza from Loreto and Moche from Lambayeque) and 140 urban Peruvians from Lima and other 33 urban areas. The aim was to evaluate, through STRs and mtDNA variability, recent migrations in urban Peruvian populations and to gain more information about their continental ancestry. STR data highlighted that most individuals (67%) of the urban Peruvian sample have a strong similarity to the Amazon Native population, whereas 22% have similarity to African populations and only ~1% to European populations. Also the maternally-transmitted mtDNA confirmed the strong Native contribution (~90% of Native American haplogroups) and the lower frequencies of African (~6%) and European (~3%) haplogroups. This study provides a detailed description of the urban Peruvian genetic structure and proposes forensic STRs as a useful tool for studying recent migrations, especially when coupled with mtDNA.


Sujet(s)
Profilage d'ADN/méthodes , ADN mitochondrial/génétique , Animaux , Systèmes CRISPR-Cas , Variation génétique/génétique , Variation génétique/physiologie , Génétique des populations/méthodes , Haplotypes/génétique , Haplotypes/physiologie , Cellules HeLa , Cellules HepG2 , Humains , Souris , Pérou , Protein-Serine-Threonine Kinases/génétique , Protein-Serine-Threonine Kinases/métabolisme , Interférence par ARN , Réaction de polymérisation en chaine en temps réel , Sérine-thréonine kinases TOR/génétique , Sérine-thréonine kinases TOR/métabolisme , Population urbaine
13.
Childs Nerv Syst ; 34(8): 1497-1509, 2018 08.
Article de Anglais | MEDLINE | ID: mdl-29785653

RÉSUMÉ

PURPOSE: Histone deacetylate inhibitors (HDACi), as valproic acid (VA), have been reported to enhance efficacy and to prevent drug resistance in some tumors, including medulloblastoma (MB). In the present study, we investigated VA role, combined to cisplatin (CDDP) in cell viability and gene expression of MB cell lines. METHODS: Dose-response curve determined IC50 values for each treatment: (1) VA single, (2) CDDP single, and (3) VA and CDDP combined. Cytotoxicity and flow cytometry evaluated cell viability after exposure to treatments. Quantitative PCR evaluated gene expression levels of AKT, CTNNB1, GLI1, KDM6A, KDM6B, NOTCH2, PTCH1, and TERT, before and after treatment. Besides, we performed next-generation sequencing (NGS) for PTCH1, TERT, and TP53 genes. RESULTS: The most effective treatment to reduce viability was combined for D283MED and ONS-76; and CDDP single for DAOY cells (p < 0.0001). TERT, GLI1, and AKT genes were overexpressed after treatments with VA. D283MED and ONS-76 cells presented variants in TERT and PTCH1, respectively and DAOY cell line presented a TP53 mutation. CONCLUSIONS: MB tumors belonging to SHH molecular subgroup, with TP53MUT, would be the ones that present high risk in relation to VA use during the treatment, while TP53WT MBs can benefit from VA therapy, both SHH and groups 3 and 4. Our study shows a new perspective about VA action in medulloblastoma cells, raising the possibility that VA may act in different patterns. According to the genetic background of MB cell, VA can stimulate cell cycle arrest and apoptosis or induce resistance to treatment via signaling pathways activation.


Sujet(s)
Survie cellulaire/effets des médicaments et des substances chimiques , Tumeurs du cervelet/métabolisme , Inhibiteurs de désacétylase d'histone/usage thérapeutique , Médulloblastome/métabolisme , Protéine p53 suppresseur de tumeur/métabolisme , Acide valproïque/usage thérapeutique , Lignée cellulaire tumorale , Survie cellulaire/physiologie , Tumeurs du cervelet/traitement médicamenteux , Tumeurs du cervelet/génétique , Relation dose-effet des médicaments , Variation génétique/physiologie , Inhibiteurs de désacétylase d'histone/pharmacologie , Humains , Médulloblastome/traitement médicamenteux , Médulloblastome/génétique , Protéine p53 suppresseur de tumeur/génétique , Acide valproïque/pharmacologie
14.
Rev. Bras. Zootec. (Online) ; 47: e20160088, 2018. tab, graf
Article de Anglais | VETINDEX | ID: biblio-1512982

RÉSUMÉ

The purpose of this study was to examine the genetic variability of the Mexican Simmental. Inbreeding was calculated by year for animals born from 1985 to 2014. Proportion of ancestors known, average equivalent complete generations, generation interval, and effective size, as well as the effective numbers of founders, ancestors, and founder genomes were calculated for animals born in six periods (1985-1989, 1990-1994, 1995-1999, 2000-2004, 2005-2009, and 2010-2014). The year 1985 was selected as the initial year to form the subpopulations since the registration of the first Simmental cattle born in Mexico began in this year. Gene contributions of ancestors with the highest genetic influence were also calculated, using data of animals born in the latter period. Coefficients of inbreeding were low, ranging from 0.0068 to 0.0165. The average number of equivalent complete generations increased from 3.71, for the 1985-1989 subpopulation, to 5.83, for the 2010-2014 subpopulation. The population showed an effective population size of 186.6 animals in the last period. The numbers of founders, ancestors, and founder genomes increased from 1985 to 2004, but decreased from 2005 to 2014. The ratio of effective number of ancestors to effective number of founders and the ratio of effective number of founder genomes to effective number of ancestors were 0.31 and 0.66 and 0.27 and 0.63 for animals born in the 2005-2009 and 2010-2014 periods, respectively, revealing loss of diversity due to bottlenecks and genetic drift in the last decade. One ancestor explained 3.4% of the total genetic variability of the progeny born from 2010 to 2014, whereas the first fifteen ancestors explained 20% of such variability. The pedigree analysis showed Mexican Simmental cattle are not currently endangered.(AU)


Sujet(s)
Animaux , Variation génétique/physiologie , Bovins/génétique , Pedigree , Croisement consanguin/méthodes
15.
Theriogenology ; 104: 105-114, 2017 Dec.
Article de Anglais | MEDLINE | ID: mdl-28822901

RÉSUMÉ

Comprehending mechanisms controlling corpus luteum (CL) angiogenesis and apoptosis in pregnant sows is essential to understand the physiological role of these processes in CL function, progesterone production and consequently in conceptus development and prenatal mortality. CL from 54 sows from two genetic groups, a commercial line (COM) and the local Piau breed (LPB), were obtained for gene expression (n = 3 COM; n = 6 LPB), histological and protein analysis (n = 3 COM; n = 3 LPB), divided in six gestational ages (seven, 15, 30, 45, 60 and 90 days). We observed differences between gestational ages in CL morphology, in which the average number of blood vessels/capillaries at 90-days was greater than at the seventh day by Tukey test. RT-qPCR analysis revealed that apoptotic genes (BAX, BCL2 and CASP3) were differentially expressed between genetic groups and gestational ages in each group. Angiogenesis genes also presented differences between genetic groups (ANGPT1) and gestational ages (MMP9, VEGFA and ANGPT1). No differences in protein abundance of steroidogenic enzymes (CYP11A1 and HSD3B1) were observed. Our findings indicate that despite the differences in gene expression, differences in corpus luteum vascularization were observed only across gestational ages, with no dissimilarities between genetic groups.


Sujet(s)
Corps jaune/physiologie , Variation génétique/physiologie , Gestation animale , Suidae/génétique , Animaux , Femelle , Régulation de l'expression des gènes/physiologie , Grossesse , Gestation animale/génétique , Gestation animale/physiologie , Suidae/physiologie
16.
Biomédica (Bogotá) ; Biomédica (Bogotá);37(2): 209-217, abr.-jun. 2017. tab, graf
Article de Espagnol | LILACS | ID: biblio-888461

RÉSUMÉ

RESUMEN Introducción. En Venezuela existen pocos reportes que describan las bases genéticas del potencial patogénico y filogenético de las cepas de Escherichia coli provenientes de hospitales. Objetivo. Determinar la diversidad genética de cepas extraintestinales de E. coli productoras de las betalactamasas TEM, SHV y CTX-M asociadas a la atención de salud. Materiales y métodos. Se estudió una colección de 12 cepas extraintestinales de E. coli con sensibilidad disminuida a las cefalosporinas de amplio espectro. La sensibilidad antimicrobiana se determinó por concentración inhibitoria mínima. La detección de los grupos filogenéticos, de los factores de virulencia y de los genes que codifican la resistencia antimicrobiana se hizo mediante la técnica de reacción en cadena de la polimerasa y la relación clonal se estableció mediante reacción en cadena de la polimerasa de elementos palindrómicos extragénicos repetitivos (Repetitive Element Palindromic-PCR, rep-PCR). Resultados. Todas las cepas analizadas presentaron resistencia a las cefalosporinas, y resistencia conjunta a quinolonas y aminoglucósidos. La distribución filogenética evidenció que los grupos A y B1 fueron los más frecuentes, seguidos por D y B2; en este último, se detectaron todos los factores de virulencia evaluados, y el gen más frecuente fue el fimH. En todas las cepas analizadas, se encontró bla CTX-M, con predominio de las bla CTX-M-8, y en dos de estas cepas se evidenció la presencia simultánea de bla CTX-M-9, variantes bla CTX-M-65 y bla CTX-M-147. Conclusión. Las cepas estudiadas demostraron diversidad genética y albergaron diferentes genes de virulencia y betalactamasas de espectro extendido (BLEE) sin predominio de ningún filogrupo en particular. Este estudio constituye el primer reporte de la variante bla CTX-M-65 en Venezuela y de la variante bla CTX-M-147 en el mundo, en cepas no relacionadas genéticamente aisladas de hospitales, situación que merece atención y la racionalización del uso de los antimicrobianos.


ABSTRACT Introduction: There are few reports from Venezuela describing the genetic basis that sustains the pathogenic potential and phylogenetics of Escherichia coli extraintestinal strains isolated in health care units. Objective: To establish the genetic diversity of extraintestinal E. coli strains producers of beta-lactamases TEM, SHV and CTX-M associated with healthcare. Materials and methods: We studied a collection of 12 strains of extraintestinal E. coli with diminished sensitivity to broad-spectrum cephalosporins. Antimicrobial susceptibility was determined by minimum inhibitory concentration. We determined the phylogenetic groups, virulence factors and genes encoding antimicrobial resistance using PCR, and clonal characterization by repetitive element palindromic-PCR rep-PCR. Results: All strains showed resistance to cephalosporins and joint resistance to quinolones and aminoglycosides. The phylogenetic distribution showed that the A and B1 groups were the most frequent, followed by D and B2. We found all the virulence factors analyzed in the B2 group, and fimH gene was the most frequent among them. We found bla CTX-M in all strains,with a higher prevalence of bla CTX-M-8; two of these strains showed coproduction of bla CTX-M-9 and were genetically identified as bla CTX-M-65 and bla CTX-M-147 by sequencing. Conclusion: The strains under study showed genetic diversity, hosting a variety of virulence genes, as well as antimicrobial resistance with no particular phylogroup prevalence. This is the first report of bla CTX-M alleles in Venezuela and in the world associated to non-genetically related strains isolated in health care units, a situation that deserves attention, as well as the rationalization of antimicrobials use.


Sujet(s)
Humains , Variation génétique/génétique , Virulence/génétique , bêta-Lactamases/génétique , Escherichia coli/isolement et purification , Gènes bactériens/génétique , Phylogenèse , Variation génétique/physiologie , Venezuela/épidémiologie , bêta-Lactamases/métabolisme , bêta-Lactamases/composition chimique , Tests de sensibilité microbienne/méthodes , Escherichia coli/composition chimique
17.
Biomedica ; 37(2): 209-217, 2017 Jun 01.
Article de Espagnol | MEDLINE | ID: mdl-28527285

RÉSUMÉ

INTRODUCTION: There are few reports from Venezuela describing the genetic basis that sustains the pathogenic potential and phylogenetics of Escherichia coli extraintestinal strains isolated in health care units. OBJECTIVE: To establish the genetic diversity of extraintestinal E. coli strains producers of betalactamases TEM, SHV and CTX-M associated with healthcare. MATERIALS AND METHODS: We studied a collection of 12 strains of extraintestinal E. coli with diminished sensitivity to broad-spectrum cephalosporins. Antimicrobial susceptibility was determined by minimum inhibitory concentration. We determined the phylogenetic groups, virulence factors and genes encoding antimicrobial resistance using PCR, and clonal characterization by repetitive element palindromic-PCR rep-PCR. RESULTS: All strains showed resistance to cephalosporins and joint resistance to quinolones and aminoglycosides. The phylogenetic distribution showed that the A and B1 groups were the most frequent, followed by D and B2. We found all the virulence factors analyzed in the B2 group, and fimH gene was the most frequent among them. We found blaCTX-M in all strains,with a higher prevalence of blaCTX-M-8; two of these strains showed coproduction of blaCTX-M-9 and were genetically identified as blaCTXM-65 and blaCTX-M-147 by sequencing. CONCLUSION: The strains under study showed genetic diversity, hosting a variety of virulence genes, as well as antimicrobial resistance with no particular phylogroup prevalence. This is the first report of blaCTX-M alleles in Venezuela and in the world associated to non-genetically related strains isolated in health care units, a situation that deserves attention, as well as the rationalization of antimicrobials use.


Sujet(s)
Escherichia coli/isolement et purification , Gènes bactériens/génétique , Variation génétique/génétique , Virulence/génétique , bêta-Lactamases/génétique , Escherichia coli/composition chimique , Variation génétique/physiologie , Humains , Tests de sensibilité microbienne/méthodes , Phylogenèse , Venezuela/épidémiologie , bêta-Lactamases/composition chimique , bêta-Lactamases/métabolisme
18.
Semin Perinatol ; 41(4): 232-243, 2017 06.
Article de Anglais | MEDLINE | ID: mdl-28545654

RÉSUMÉ

Genetic tools such as microarray and next-generation sequencing have initiated a new era for the diagnosis and management of patients with disorders of sex development (DSDs). These tools supplement the traditional approach to the evaluation and care of infants, children, and adolescents with DSDs. These tests can detect genetic variations known to be associated with DSDs, discover novel genetic variants, and elucidate novel mechanisms of gene regulation. Herein, we discuss these tests and their role in the management of patients with DSDs.


Sujet(s)
Troubles du développement sexuel de sujets 46, XX/diagnostic , Troubles du développement sexuel de sujets 46, XX/génétique , Compétence clinique , Troubles du développement sexuel de sujets 46, XY/diagnostic , Troubles du développement sexuel de sujets 46, XY/génétique , Troubles du développement sexuel/génétique , Variation génétique/physiologie , Troubles du développement sexuel de sujets 46, XX/psychologie , Adolescent , Enfant , Troubles du développement sexuel de sujets 46, XY/psychologie , Femelle , Identité de genre , Dépistage génétique , Humains , Nouveau-né , Mâle , Parents/enseignement et éducation , Parents/psychologie , Éducation du patient comme sujet , Mutation ponctuelle , Guides de bonnes pratiques cliniques comme sujet , Développement sexuel
19.
R. bras. Ci. avíc. ; 18(3): 519-523, Jul-Set. 2016. tab, ilus
Article de Anglais | VETINDEX | ID: vti-15615

RÉSUMÉ

Polymorphism of three quail communities was analyzed by using 12 microsatellite markers in this paper, aiming to provide scientific references for the evaluation, protection and utilization of quail genetic resources in China. Results demonstrated that the number of observed alleles by 12 microsatellite markers ranges between 4~7. The average polymorphism information contents (PIC) of the Chinese yellow quail, the Chinese black quail and the Korean quail, as detected by 12 microsatellite markers, are 0.6853, 0.6401 and 0.6565,respectively, and average heterozygosity values are 0.7333, 0.6957 and 0.7111, respectively. This indicates that the Chinese yellow quail has the richest genetic polymorphism. According to cluster analysis, the Chinese black quail and the Korean quail have the smallest genetic distance (0.0628), which reflects that they have the closest genetic relationship. The genetic distance between the Chinese yellow quail and the Korean quail is 0.0951. Therefore, the Chinese black quail and the Korean quail are clustered together firstly, and then the Chinese yellow quail.(AU)


Sujet(s)
Animaux , Variation génétique/physiologie , Coturnix/génétique , Polymorphisme génétique , Répétitions microsatellites/génétique , Chine , Volaille/génétique , Allèles
20.
Rev. bras. ciênc. avic ; 18(3): 519-523, Jul-Set. 2016. tab, ilus
Article de Anglais | VETINDEX | ID: biblio-1490276

RÉSUMÉ

Polymorphism of three quail communities was analyzed by using 12 microsatellite markers in this paper, aiming to provide scientific references for the evaluation, protection and utilization of quail genetic resources in China. Results demonstrated that the number of observed alleles by 12 microsatellite markers ranges between 4~7. The average polymorphism information contents (PIC) of the Chinese yellow quail, the Chinese black quail and the Korean quail, as detected by 12 microsatellite markers, are 0.6853, 0.6401 and 0.6565,respectively, and average heterozygosity values are 0.7333, 0.6957 and 0.7111, respectively. This indicates that the Chinese yellow quail has the richest genetic polymorphism. According to cluster analysis, the Chinese black quail and the Korean quail have the smallest genetic distance (0.0628), which reflects that they have the closest genetic relationship. The genetic distance between the Chinese yellow quail and the Korean quail is 0.0951. Therefore, the Chinese black quail and the Korean quail are clustered together firstly, and then the Chinese yellow quail.


Sujet(s)
Animaux , Chine , Coturnix/génétique , Polymorphisme génétique , Répétitions microsatellites/génétique , Variation génétique/physiologie , Allèles , Volaille/génétique
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