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Javier Ca?ón Paolo Alexandrino Isabel Bessa Carlos Carleos Yolanda Carretero Susana Dunner Nuno Ferran David Garcia Jordi Jordana Denis Lalo? Albano Pereira Armand Sanchez Katayoun Moazami-Goudarzi 《遗传、选种与进化》2001,33(3):311-332
This study was undertaken to determine the genetic structure, evolutionary relationships, and the genetic diversity among 18 local cattle breeds from Spain, Portugal, and France using 16 microsatellites. Heterozygosities, estimates of Fst, genetic distances, multivariate and diversity analyses, and assignment tests were performed. Heterozygosities ranged from 0.54 in the Pirenaica breed to 0.72 in the Barrosã breed. Seven percent of the total genetic variability can be attributed to differences among breeds (mean Fst = 0.07; P < 0.01). Five different genetic distances were computed and compared with no correlation found to be significantly different from 0 between distances based on the effective size of the population and those which use the size of the alleles. The Weitzman recursive approach and a multivariate analysis were used to measure the contribution of the breeds diversity. The Weitzman approach suggests that the most important breeds to be preserved are those grouped into two clusters: the cluster formed by the Mirandesa and Alistana breeds and that of the Sayaguesa and Tudanca breeds. The hypothetical extinction of one of those clusters represents a 17% loss of diversity. A correspondence analysis not only distinguished four breed groups but also confirmed results of previous studies classifying the important breeds contributing to diversity. In addition, the variation between breeds was sufficiently high so as to allow individuals to be assigned to their breed of origin with a probability of 99% for simulated samples. 相似文献
294.
Genetic diversity at 13 equine microsatellite loci was compared in five endangered Spanish donkey breeds: Andaluza, Catalana, Mallorquina, Encartaciones and Zamorano-Leonesa. All of the equine microsatellites used in this study were amplified and were polymorphic in the domestic donkey breeds with the exception of HMS1, which was monomorphic, and ASB2, which failed to amplify. Allele number, frequency distributions and mean heterozygosities were very similar among the Spanish donkey breeds. The unbiased expected heterozygosity (HE) over all the populations varied between 0.637 and 0.684 in this study. The low GST value showed that only 3.6% of the diversity was between breeds (P < 0.01). Significant deviations from Hardy-Weinberg equilibrium were shown for a number of locus-population combinations, except HMS5 that showed agreement in all analysed populations. The cumulative exclusion probability (PE) was 0.999 in each breed, suggesting that the loci would be suitable for donkey parentage testing. The constructed dendrogram from the DA distance matrix showed little differentiation between Spanish breeds, but great differentiation between them and the Moroccan ass and also with the horse, used as an outgroup. These results confirm the potential use of equine microsatellite loci as a tool for genetic studies in domestic donkey populations, which could also be useful for conservation plans. 相似文献
295.
Miguel Angel Pujana Monica Gratacós Jordi Corral Isabel Banchs Aurora Sánchez David Genís Carlos Cervera Víctor Volpini X. Estivill 《Human genetics》1997,101(1):18-21
Genetic anticipation – increasing severity and a decrease in the age of onset with successive generations of a pedigree –
is clearly present in autosomal dominant cerebellar ataxia (ADCA). Anticipation is correlated with expansion of the CAG/CTG
repeat sequence to sizes above those in the normal range through the generations of a pedigree. Genetic heterogeneity has
been demonstrated for ADCA, with four cloned genes (SCA1, SCA2, SCA3/MJD, and SCA6) and three mapped loci (SCA4, SCA5 and
SCA7). Another related dominant ataxia, dentatorubral-pallidoluysian atrophy (DRPLA), presents anticipation with CAG/CTG repeat
expansions. We had previously analysed ADCA patients who had not shown repeat expansions in cloned genes for CAG/CTG repeat
expansions by the repeat expansion detection method (RED) and had detected expansions of between 48 and 88 units in 17 unrelated
familial cases. We present here an analysis of 13 genes and expressed sequence tags (ESTs) containing 10 or more CAG/ CTG
repeat sequences selected from public databases in the 17 unrelated ADCA patients. Of the 13 selected genes and ESTs, 9 were
found to be polymorphic with heterozygosities ranging between 0.09 and 0.80 and 2 to 17 alleles. In ADCA patients none of
the loci showed expansions above the normal range of the CAG/CTG repeat sequences, excluding them as the mutation causing
ADCA.
Received: 28 May 1997 / Accepted: 30 June 1997 相似文献
296.
Pere Fullana i Palmer Rita Puig Alba Bala Grau Baquero Jordi Riba Marco Raugei 《Journal of Industrial Ecology》2011,15(3):458-475
Life cycle assessment (LCA) is a widely accepted methodology to support decision‐making processes in which one compares alternatives, and that helps prevent shifting of environmental burdens along the value chain or among impact categories. According to regulation in the European Union (EU), the movement of waste needs to be reduced and, if unavoidable, the environmental gain from a specific waste treatment option requiring transport must be larger than the losses arising from transport. The EU explicitly recommends the use of LCA or life cycle thinking for the formulation of new waste management plans. In the last two revisions of the Industrial Waste Management Programme of Catalonia (PROGRIC), the use of a life cycle thinking approach to waste policy was mandated. In this article we explain the process developed to arrive at practical life cycle management (LCM) from what started as an LCA project. LCM principles we have labeled the “3/3” principle or the “good enough is best” principle were found to be essential to obtain simplified models that are easy to understand for legislators and industries, useful in waste management regulation, and, ultimately, feasible. In this article, we present the four models of options for the management of waste solvent to be addressed under Catalan industrial waste management regulation. All involved actors concluded that the models are sufficiently robust, are easy to apply, and accomplish the aim of limiting the transport of waste outside Catalonia, according to the principles of proximity and sufficiency. 相似文献
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298.
Decorin is the archetypal small leucine rich repeat proteoglycan of the vertebrate extracellular matrix (ECM). With its glycosaminoglycuronan chain, it is responsible for stabilizing inter-fibrillar organization. Type I collagen is the predominant member of the fibrillar collagen family, fulfilling both organizational and structural roles in animal ECMs. In this study, interactions between decoron (the decorin core protein) and binding sites in the d and e1 bands of the type I collagen fibril were investigated through molecular modeling of their respective X-ray diffraction structures. Previously, it was proposed that a model-based, highly curved concave decoron interacts with a single collagen molecule, which would form extensive van der Waals contacts and give rise to strong non-specific binding. However, the large well-ordered aggregate that is the collagen fibril places significant restraints on modes of ligand binding and necessitates multi-collagen molecular contacts. We present here a relatively high-resolution model of the decoron-fibril collagen complex. We find that the respective crystal structures complement each other well, although it is the monomeric form of decoron that shows the most appropriate shape complementarity with the fibril surface and favorable calculated energies of interaction. One molecule of decoron interacts with four to six collagen molecules, and the binding specificity relies on a large number of hydrogen bonds and electrostatic interactions, primarily with the collagen motifs KXGDRGE and AKGDRGE (d and e1 bands). This work helps us to understand collagen-decorin interactions and the molecular architecture of the fibrillar ECM in health and disease. 相似文献
299.
The study of traces made by microendoliths on Neopycnodonte cochlear shells from a coquina in the Vilacolum area (Alt Empordà basin) has permitted us to identify for the first time 18 ichnotaxa in the Lower Pliocene sediments of the NW Mediterranean. A shallow, euphotic environment with local shaded zones (corresponding to deep shallow conditions) is proposed for this shell bed, owing to the presence of abundant heterotroph microborings and rare cyanobacterial traces as well as to the high number of Rhopalia catenata and Ichnoreticulina elegans. This refines a former interpretation, mainly based on body fossils and macroborings, which suggested simply a shallow depositional environment. The ichnospecies Ichnoreticulina elegans, Rhopalia catenata, ?R. clavigera, Saccomorpha clava, S. terminalis, Polyactina araneola, Entobia mikra, Orthogonum lineare and Aurimorpha varia are identified for the first time in marine Pliocene materials, thus furnishing a more complete picture of the temporal span of some microborers. 相似文献
300.
Manel Puig-Domingo Raúl M. Luque Jordi L. Reverter Laura M. López-Sánchez Manuel D. Gahete Michael D. Culler Gonzalo Díaz-Soto Francisco Lome?a Mattia Squarcia José Luis Mate Mireia Mora Laureano Fernández-Cruz Oscar Vidal Antonio Alastrué Jose Balibrea Irene Halperin Dídac Mauricio Justo P. Casta?o 《PloS one》2014,9(1)
Somatostatin receptors (ssts) are expressed in thyroid cancer cells, but their biological significance is not well understood. The aim of this study was to assess ssts in well differentiated (WDTC) and poorly differentiated thyroid cancer (PDTC) by means of imaging and molecular tools and its relationship with the efficacy of somatostatin analog treatment. Thirty-nine cases of thyroid carcinoma were evaluated (20 PDTC and 19 WDTC). Depreotide scintigraphy and mRNA levels of sst-subtypes, including the truncated variant sst5TMD4, were carried out. Depreotide scans were positive in the recurrent tumor in the neck in 6 of 11 (54%) PDTC, and in those with lung metastases in 5/11 cases (45.4%); sst5TMD4 was present in 18/20 (90%) of PDTC, being the most densely expressed sst-subtype, with a 20-fold increase in relation to sst2. In WDTC, sst2 was the most represented, while sst5TMD4 was not found; sst2 was significantly increased in PDTC in comparison to WDTC. Five depreotide positive PDTC received octreotide for 3–6 months in a pilot study with no changes in the size of the lesions in 3 of them, and a significant increase in the pulmonary and cervical lesions in the other 2. All PDTC patients treated with octreotide showed high expression of sst5TMD4. ROC curve analysis demonstrated that only sst5TMD4 discriminates between PDTC and WDTC. We conclude that sst5TMD4 is overexpressed in PDTC and may be involved in the lack of response to somatostatin analogue treatment. 相似文献