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1.
New Phytol ; 220(2): 636-650, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30016546

RESUMO

Reconstructing phylogenetic relationships at the micro- and macroevoutionary levels within the same tree is problematic because of the need to use different data types and analytical frameworks. We test the power of target enrichment to provide phylogenetic resolution based on DNA sequences from above species to within populations, using a large herbarium sampling and Euphorbia balsamifera (Euphorbiaceae) as a case study. Target enrichment with custom probes was combined with genome skimming (Hyb-Seq) to sequence 431 low-copy nuclear genes and partial plastome DNA. We used supermatrix, multispecies-coalescent approaches, and Bayesian dating to estimate phylogenetic relationships and divergence times. Euphorbia balsamifera, with a disjunct Rand Flora-type distribution at opposite sides of Africa, comprises three well-supported subspecies: western Sahelian sepium is sister to eastern African-southern Arabian adenensis and Macaronesian-southwest Moroccan balsamifera. Lineage divergence times support Late Miocene to Pleistocene diversification and climate-driven vicariance to explain the Rand Flora pattern. We show that probes designed using genomic resources from taxa not directly related to the focal group are effective in providing phylogenetic resolution at deep and shallow evolutionary levels. Low capture efficiency in herbarium samples increased the proportion of missing data but did not bias estimation of phylogenetic relationships or branch lengths.


Assuntos
Genética Populacional , Genômica , Filogenia , Genes de Plantas , Geografia
2.
Mol Phylogenet Evol ; 63(3): 866-76, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22445449

RESUMO

This paper examines the phylogeny of Erodium subsect. Petraea, a group of six morphologically and genetically very similar species from the mountains of the western Mediterranean. Combined trnL-F-ITS analysis was unable to determine the phylogenetic relationships of these species owing to sequence similarity. AFLP fragment analysis showed different populations to cluster in six closely related phylogroups that partially coincided with morphological species. In the Iberian Peninsula, high temperatures during interstadial periods probably impeded the survival of these species at low altitudes, and their populations may have been forced to migrate northward within Iberia or remain isolated on high mountains. AFLP variation suggests that this might have led to their differentiation into groups and speciation during interglacials, but it probably also provided the basis for recurrent recolonisations and the mixing of neighbouring populations at the last glacial maxima. The genetic diversity of the two Erodium lineages suggests two migration episodes took place from southern Iberia towards the north, with one lineage migrating via western Iberia and the other via eastern Iberia. The patterns of genetic diversity observed in populations of 56 European species (27 genera) leads to the hypothesis that disparate proportions of unique polymorphic fragments are the result of the evolutionary histories of their mountain populations irrespective of the currently recognised species.


Assuntos
Variação Genética , Geraniaceae/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Teorema de Bayes , Genes de Plantas , Especiação Genética , Funções Verossimilhança , Cadeias de Markov , Região do Mediterrâneo , Modelos Genéticos , Método de Monte Carlo , Tipagem de Sequências Multilocus , Análise Multivariada , Filogeografia , Polimorfismo Genético , Alinhamento de Sequência , Análise de Sequência de DNA
3.
Am J Orthod Dentofacial Orthop ; 140(1): 38-43, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21724085

RESUMO

INTRODUCTION: Although chincups are the preferred treatment for growing children with mandibular prognathism, the mechanism by which chincups improve this condition remains unclear. The aim of this study was to use geometric morphometrics to evaluate changes in the shape of the mandible of prognathic children treated with a chincup. METHODS: Geometric morphometrics were used to evaluate the short-term mandibular shape changes in 50 prognathic children treated with chincups compared with 40 untreated matched controls. Twenty-one 2-dimensional mandibular landmarks from cephalograms taken before and after 36 months of treatment or observation were analyzed by Procrustes superimposition and thin plate spline. RESULTS: Permutation tests of the treated patients showed highly significant differences in the mandibular shapes before and after treatment, and compared with the control group after the observation period. The thin plate spline grid deformations indicated more rectangular mandibular configuration, forward condyle orientation, condyle neck compression, gonial area compression, and symphysis narrowing. CONCLUSIONS: Early chincup treatment widely modifies the mandibular shape of prognathic children to improve Class III malocclusion.


Assuntos
Aparelhos de Tração Extrabucal , Má Oclusão Classe III de Angle/terapia , Mandíbula/anatomia & histologia , Prognatismo/terapia , Estudos de Casos e Controles , Cefalometria/estatística & dados numéricos , Criança , Queixo/anatomia & histologia , Queixo/patologia , Feminino , Humanos , Análise dos Mínimos Quadrados , Estudos Longitudinais , Masculino , Mandíbula/patologia , Análise Multivariada , Estudos Retrospectivos , Técnica de Subtração
4.
Arch Latinoam Nutr ; 53(1): 21-7, 2003 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-12942867

RESUMO

To determine the prevalence of anemia, and iron (ID) and vitamin A deficiencies aiming at their prevention, 414 children between 6 and 24 months of age, were randomly selected from the whole province of Chaco. A sociodemographic survey was implemented, and hemoglobin (Hb), plasma ferritin and retinol were measured. Anemia prevalence (Hb < 110 g/L) was 66.4%, without differences between age groups, and included 18% with Hb < 90 g/L. These cases were significantly less in children 6-8 month of age (5.1%) than in the others (approximately equal to 20%) (P: 0.007). Mean Hb was also higher in 6-8 months old children and was associated with lower prevalence of ID (ferritin < 12 micrograms/L) (p < 0.000) but not with age (p = 0.8865). ID already present, however, in 36.6% of children in this age group, reached a prevalence of 72.9% in children older than 18 months. Anemia prevalence was significantly higher in males, in children whose birth weight was < 3000 g, in those who had never taken iron supplements and among the poor, both structural and by income. Retinol values < 20 micrograms/dl occurred only in 5.1% of children. Iron nutrition prior to, during pregnancy and in children during the first 2 years of life must be improved by joining strategies based on community empowerment aimed at improving dietary iron, assuring effective preventive supplementation and promoting the opportune umbilical cord ligation.


Assuntos
Anemia Ferropriva/epidemiologia , Deficiências de Ferro , Deficiência de Vitamina A/epidemiologia , Anemia/sangue , Anemia/epidemiologia , Anemia/prevenção & controle , Anemia Ferropriva/sangue , Anemia Ferropriva/prevenção & controle , Argentina/epidemiologia , Feminino , Ferritinas/sangue , Acessibilidade aos Serviços de Saúde , Hemoglobinas/análise , Humanos , Lactente , Masculino , Prevalência , Fatores Socioeconômicos , Deficiência de Vitamina A/sangue , Deficiência de Vitamina A/prevenção & controle
5.
Arch Latinoam Nutr ; 52(4): 336-43, 2002 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-12868272

RESUMO

Aiming at their prevention, to determine the prevalence of gestational iron deficiency and anemia, considering access to health care and associations with social and biological variables in the Province of el Chaco, Argentina. Three hundred and sixty four, randomly selected pregnant women from the whole province participated. Mean Hemoglobin (Hb) +/- SD dropped progressively from 118.4 +/- 11.0 to 112.1 +/- 11.5 g/L (p = 0.015) between the 1st and the 3rd gestational trimesters. Anemia prevalence (Hb < 110 g/L) was 17.4, 26.5 and 35.8%. From the 1st to the 3rd trimesters. Second trimester prevalence was 14.1% using Hb < 105 g/L as recently suggested. The ferritin geometric mean during the progressive gestational trimesters were 28.9; 16.0 and 11.1 micrograms/L. 21.7, 40.5 and 60.5% had ferritins < 12 micrograms/L, and 39.1, 58.9 and 83.2% had ferritins < 20 micrograms/L in these respective trimesters (p < 0.004 between trimesters in both cases). Both iron deficiency and anemia were significantly greater in women with unfinished primary education and with interpregnancy interval < 1 year. Seventy five percent of women had adequate number of antenatal visits but only 23% were taking iron supplements and 10% had stopped taking them. The prevention and correction of gestational iron deficiency and anemia must focus on the preconceptional period (inter-pregnancy spacing and increasing iron intake using all available means) as well as during pregnancy improving adherence to iron supplements by means of motivation of health workers and community.


Assuntos
Anemia Ferropriva/epidemiologia , Deficiências de Ferro , Complicações Hematológicas na Gravidez/epidemiologia , Adulto , Anemia Ferropriva/prevenção & controle , Argentina/epidemiologia , Estudos Transversais , Feminino , Ferritinas/sangue , Hemoglobinas/análise , Humanos , Gravidez , Complicações Hematológicas na Gravidez/prevenção & controle , Prevalência
9.
Resistencia; Chaco. Dirección de Nutrición; 1965. 39 p. ilus, tab.
Monografia em Espanhol | BINACIS | ID: biblio-1192926

RESUMO

Peso y talla del niño de 1 a 5 años como signos básicos del estado nutricional y aspectos culturales de la alimentación familiar y su relación con la situación socioeconómica


Assuntos
Feminino , Masculino , Humanos , Lactente , Comportamento Alimentar , Nutrição da Criança , Peso-Estatura , Nutrição do Lactente , Peso-Idade , Saúde Pública/história
10.
Resistencia; Chaco. Dirección de Nutrición; 1965. 39 p. ilus, Tab. (66324).
Monografia em Espanhol | BINACIS | ID: bin-66324

RESUMO

Peso y talla del niño de 1 a 5 años como signos básicos del estado nutricional y aspectos culturales de la alimentación familiar y su relación con la situación socioeconómica


Assuntos
Humanos , Pré-Escolar , Lactente , Feminino , Masculino , Nutrição da Criança , Peso-Estatura , Comportamento Alimentar , Saúde Pública/história , Nutrição do Lactente , Peso-Idade
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