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1.
Mol Ecol ; 17(13): 3147-59, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18522691

ABSTRACT

Today, the Seasonally Dry Tropical Forests (SDTF) of eastern South America occur as large, well-defined nuclei (e.g. Caatinga in the northeast) and as smaller enclaves within other vegetations (e.g. Cerrado and Chaco). In order to infer the way the present SDTF distribution was attained, the genetic structure of Astronium urundeuva, a tree confined to SDTF, was assessed using two chloroplast spacers and nine microsatellite loci. Five haplotypes were identified, whose distribution was spatially structured. The distribution of the two most common and divergent haplotypes suggested former vicariance and progressive divergence due to isolation. More recent range expansions of these two lineages subsequently occurred, leading to a secondary contact at the southern limit of the Caatinga SDTF nucleus. The multilocus-Bayesian approach using microsatellites consistently identified three groups of populations (Northeast, Central and Southwest). Isolation by distance was found in Northeast and Southwest groups whereas admixture was detected in the Central group, located at the transition between Caatinga and Cerrado domains. All together, the results support the existence of range expansions and secondary contact in the Central group. This study provides arguments that favour the existence of a previously more continuous formation of SDTF in eastern South America.


Subject(s)
Anacardiaceae/genetics , Trees/genetics , Tropical Climate , Anacardiaceae/classification , Anacardiaceae/growth & development , Cluster Analysis , DNA, Chloroplast/chemistry , DNA, Chloroplast/genetics , Ecosystem , Genetic Variation , Genetics, Population , Geography , Microsatellite Repeats/genetics , Molecular Sequence Data , Phylogeny , Seasons , Sequence Analysis, DNA , South America , Trees/classification , Trees/growth & development
2.
Stroke ; 29(4): 785-92, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9550512

ABSTRACT

BACKGROUND AND PURPOSE: Arm function recovery is notoriously poor in stroke patients. The effect of treatment modalities, particularly those directed at improving upper limb function, has been studied primarily in chronic stroke patients. The purpose of this study was to investigate the effect of a specific therapeutic intervention on arm function in the acute phase after stroke. METHODS: In a single-blind, randomized, controlled multicenter trial, 100 consecutive patients were allocated to either an experimental group that received an additional treatment of sensorimotor stimulation or to a control group. The intervention was applied for 6 weeks. Patients were evaluated for level of impairment (Brunnström-Fugl-Meyer test) and disability (Action Research Arm test, Barthel Index) before, midway, and after the intervention period and at follow-up 6 and 12 months after stroke. RESULTS: Patients in the experimental group performed better on the Brunnström-Fugl-Meyer test than those in the control group throughout the study period, but differences were significant only at follow-up. Results on the Action Research Arm test and Barthel Index revealed no effect at the level of disability. The effect of the therapy was attributed to the repetitive stimulation of muscle activity. The treatment was most effective in patients with a severe motor deficit and hemianopia or hemi-inattention. No adverse effects due to the intervention were found. CONCLUSIONS: Adding a specific intervention during the acute phase after stroke improved motor recovery, which was apparent 1 year later. These results emphasize the potential beneficial effect of therapeutic interventions for the arm.


Subject(s)
Arm/innervation , Cerebrovascular Disorders/complications , Hemiplegia/therapy , Adult , Aged , Aged, 80 and over , Analysis of Variance , Hemiplegia/etiology , Humans , Middle Aged , Motor Activity/physiology , Physical Stimulation , Prognosis , Single-Blind Method
3.
Mol Phylogenet Evol ; 7(2): 145-57, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9126556

ABSTRACT

In a previous study we examined the phylogeny of four families related to the angiosperm order Celastrales based on chloroplast rbcL 5' flanking sequences. We have added here several additional dicots, sampled from 6 of the 7 families of Celastrales sensu Cronquist and 19 putatively related genera. Based on a cladistic analysis of these DNA sequences, the order Celastrales appears polyphyletic: it is here restricted to Celastraceae (including Hippocrateaceae and Brexia) with Parnassia as sister; Aquifoliaceae plus Helwingia are included in Asteridae. Neither Salvadoraceae nor Geissolomataceae, Icacinaceae, Phellinaceae, Aextoxicaceae, Corynocarpaceae, Dichapetalaceae, Stackhousiaceae, or Goupiaceae are related to Celastrales. The usefulness of this noncoding region is discussed and the influence of the A + T content of neighboring bases on the increase of transversions is also observed as previously shown in chloroplast noncoding regions of monocots.


Subject(s)
DNA, Chloroplast/genetics , Phylogeny , Plants/genetics , Base Sequence , DNA Primers/genetics , Evolution, Molecular , Molecular Sequence Data , Plants/classification , Sequence Homology, Nucleic Acid , Species Specificity
4.
Theor Appl Genet ; 90(7-8): 1138-41, 1995 Jun.
Article in English | MEDLINE | ID: mdl-24173075

ABSTRACT

The chloroplastic atpB-rbcL spacer and the first 53 codons of the rbcL coding sequence was sequenced for 40 apple cultivars and 15 wild species. This chloroplast DNA region is 904 base pairs long, and only five mutations sites were found among the tested samples. Although the cpDNA variation was low, some parentages are proposed based on the maternal inheritance of plastid DNA: the male and female parents are specified, or else suggested, for Worcester, Discovery, Starking, Starkrimson, Kidd's Orange Red, Priscilla, and Gloster, as well as for the putative wild origin for Malus x domestica.

5.
Mol Phylogenet Evol ; 3(1): 27-37, 1994 Mar.
Article in English | MEDLINE | ID: mdl-8025727

ABSTRACT

The region between the rbcL and atpB chloroplast genes and the first 53 codons of the rbcL gene have been sequenced for 19 species of angiosperms. Nine of these belong to the four largest families within the order Celastrales sensu Cronquist (i.e., Aquifoliaceae s.l., Icacinaceae, Celastraceae, and Hippocrateaceae). Both phenetic and cladistic approaches were used to test the monophyly of the order and to specify its relationships with Euphorbiaceae, Rhamnaceae, Rosaceae, and Theaceaea. Based upon this molecular analysis, the order Celastrales is polyphyletic and is divided into two major clades. The first group, containing Aquifoliaceae s.l. and Icacina, is related to Camellia (Theaceae). The second, containing Euonymus (Celastraceae), Hippocratea, and Salacia (Hippocrateaceae), is related to Euphorbia (Euphorbiaceae).


Subject(s)
Phylogeny , Plants/classification , Ribulose-Bisphosphate Carboxylase/genetics , Base Sequence , Codon , DNA , Molecular Sequence Data , Plants/enzymology , Plants/genetics , Sequence Homology, Nucleic Acid
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