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41.
S. A. Angioi D. Rau G. Attene L. Nanni E. Bellucci G. Logozzo V. Negri P. L. Spagnoletti Zeuli R. Papa 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(5):829-843
This study focuses on the expansion of Phaseolus vulgaris in Europe. The pathways of distribution of beans into and across Europe were very complex, with several introductions from
the New World that were combined with direct exchanges between European and other Mediterranean countries. We have analyzed
here six chloroplast microsatellite (cpSSR) loci and two unlinked nuclear loci (for phaseolin types and Pv-shatterproof1). We have assessed the genetic structure and level of diversity of a large collection of European landraces of P. vulgaris (307) in comparison to 94 genotypes from the Americas that are representative of the Andean and Mesoamerican gene pools.
First, we show that most of the European common bean landraces (67%) are of Andean origin, and that there are no strong differences
across European regions for the proportions of the Andean and Mesoamerican gene pools. Moreover, cytoplasmic diversity is
evenly distributed across European regions. Secondly, the cytoplasmic bottleneck that was due to the introduction of P. vulgaris into the Old World was very weak or nearly absent. This is in contrast to evidence from nuclear analyses that have suggested
a bottleneck of greater intensity. Finally, we estimate that a relatively high proportion of the European bean germplasm (about
44%) was derived from hybridization between the Andean and Mesoamerican gene pools. Moreover, although hybrids are present
everywhere in Europe, they show an uneven distribution, with high frequencies in central Europe, and low frequencies in Spain
and Italy. On the basis of these data, we suggest that the entire European continent and not only some of the countries therein
can be regarded as a secondary diversification center for P. vulgaris. Finally, we outline the relevance of these inter-gene pool hybrids for plant breeding. 相似文献
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43.
C Parlapiano M C Borgia G Tonnarini G Giancaspro F Pizzuto E Campana T Giovanniello P Pantone G M Vincentelli F Alegiani M Negri 《Peptides》2001,22(7):1181-1182
Met-enkephalin (Met-enk) has been demonstrated to modulate myocardial-ischemia mechanisms via the opioid receptors, but no studies are now available on Met-enk levels in the coronary circulation.In this experience Met-enk levels were evaluated in aortic root and in coronary sinus at baseline (T0), during PTCA induced transient ischemia (T1) and during reperfusion (T2). No significant differences were found at any time. Thus, it appears that there is no Met-enk extraction from the coronary circulation during provoked myocardial ischemia and no Met-enk release from the ischemic heart. 相似文献
44.
PTX3 interacts with inter-alpha-trypsin inhibitor: implications for hyaluronan organization and cumulus oophorus expansion 总被引:1,自引:0,他引:1
Scarchilli L Camaioni A Bottazzi B Negri V Doni A Deban L Bastone A Salvatori G Mantovani A Siracusa G Salustri A 《The Journal of biological chemistry》2007,282(41):30161-30170
Pentraxin 3 (PTX3) and heavy chains (HCs) of inter-alpha-trypsin inhibitor (IalphaI) are essential for hyaluronan (HA) organization within the extracellular matrix of the cumulus oophorus, which is critical for in vivo oocyte fertilization and female fertility. In this study, we examined the possibility that these molecules interact and cooperate in this function. We show that HCs and PTX3 colocalize in the cumulus matrix and coimmunoprecipitate from cumulus matrix extracts. Coimmunoprecipitation experiments and solid-phase binding assays performed with purified human IalphaI and recombinant PTX3 demonstrate that their interaction is direct and not mediated by other matrix components. PTX3 does not bind to IalphaI subcomponent bikunin and, accordingly, bikunin does not compete for the binding of PTX3 to IalphaI, indicating that PTX3 interacts with IalphaI subcomponent HC only. Recombinant PTX3-specific N-terminal region, but not the PTX3-pentraxin C-terminal domain, showed the same ability as full-length protein to bind to HCs and to enable HA organization and matrix formation by Ptx3(-/-) cumulus cell oocyte complexes cultured in vitro. Furthermore, a monoclonal antibody raised against PTX3 N terminus, which inhibits PTX3/IalphaI interaction, also prevents recombinant full-length PTX3 from restoring a normal phenotype to in vitro-cultured Ptx3(-/-) cumuli. These results indicate that PTX3 directly interacts with HCs of IalphaI and that such interaction is essential for organizing HA in the viscoelastic matrix of cumulus oophorus, highlighting a direct functional link between the two molecules. 相似文献
45.
46.
The principles driving the organization of the ventral object-processing stream remain unknown. Here, we show that stimulus-specific repetition suppression (RS) in one region of the ventral stream is biased according to motor-relevant properties of objects. Quantitative analysis confirmed that this result was not confounded with similarity in visual shape. A similar pattern of biases in RS according to motor-relevant properties of objects was observed in dorsal stream regions in the left hemisphere. These findings suggest that neural specificity for "tools" in the ventral stream is driven by similarity metrics computed over motor-relevant information represented in dorsal structures. Support for this view is provided by converging results from functional connectivity analyses of the fMRI data and a separate neuropsychological study. More generally, these data suggest that a basic organizing principle giving rise to "category specificity" in the ventral stream may involve similarity metrics computed over information represented elsewhere in the brain. 相似文献
47.
Marangoni F Colombo C Martiello A Negri E Galli C 《Prostaglandins, leukotrienes, and essential fatty acids》2007,76(2):87-92
Limited data are available on the fatty acid (FA) composition of circulating lipids and the associations with diet, physiological and pathological conditions, due to the complexity and costs of the analytical process. The aim of our study was to evaluate the FA composition in 108 healthy subjects and to correlate the data with gender, pregnancy, dietary habits, lifestyle, and short-term controlled intake of n-3 FA, using an innovative analytical approach for the collection and processing of blood samples. Ten subjects were also supplemented with n-3 polyunsaturated FA as smoked salmon or capsules for 3 weeks. The resulting blood FA composition was affected by gender, pregnancy, diet and smoking. The data indicate that this new analytical methodology is suitable for assessing associations between circulating FA and various parameters in large population groups, and is applicable to epidemiological studies and in the assessment of the effects of controlled FA supplementation in clinical studies. 相似文献
48.
Vera MF da Silva Anthony M Carter Carlos E Ambrosio Ana F Carvalho Marina Bonatelli Marcelo C Lima Angelica Maria Miglino 《Reproductive biology and endocrinology : RB&E》2007,5(1):26-6
A recent reassessment of the phylogenetic affinities of cetaceans makes it timely to compare their placentation with that
of the artiodactyls. We studied the placentae of two sympatric species of dolphin from the Amazon River Basin, representing
two distinct families. The umbilical cord branched to supply a bilobed allantoic sac. Small blood vessels and smooth muscle
bundles were found within the stroma of the cord. Foci of squamous metaplasia occurred in the allanto-amnion and allantochorion.
The interhemal membrane of the placenta was of the epitheliochorial type. Two different types of trophoblastic epithelium
were seen. Most was of the simple columnar type and indented by fetal capillaries. However, there were also areolar regions
with tall columnar trophoblast and these were more sparsely supplied with capillaries. The endometrium was well vascularised
and richly supplied with actively secreting glands. These findings are consistent with the current view that Cetacea are nested
within Artiodactyla as sister group to the hippopotamids. 相似文献
49.
Evidence for strong genetic structure in European populations of the little owl Athene noctua
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Irene Pellegrino Alessandro Negri Giovanni Boano Marco Cucco Torsten N. Kristensen Cino Pertoldi Ettore Randi Martin Šálek Nadia Mucci 《Journal of avian biology》2015,46(5):462-475
The little owl Athene noctua is a widespread species in Europe. This mainly sedentary owl experienced reduction in population sizes in some areas due to habitat loss and modification of the landscape. To assess the genetic structure of the populations of western and central Europe, we analysed 333 specimens from 15 geographical areas at 13 microsatellite loci. Statistical analyses and Bayesian clustering procedures detected two major genetically distinct clusters, the first distributed from Portugal to the Czech Republic and the second from the Balkans to Italy. The second cluster was further split into three groups, located in Italy, Sardinia and the Balkans. These groups match four previously‐described mtDNA haplogroups, and probably originated from the isolation of little owl populations in Sardinia and in three glacial refugia (Iberia, south Italy and Balkans) during the ice ages. High genetic admixture was recorded in central and northern Europe, probably as a consequence of the expansion from the refugia during interglacial. The main colonization route originated from the Iberian Peninsula towards central and northern Europe. Contact zones with colonization events from Italy and the Balkans were detected respectively in northern Italy and central Europe. Genetic indices show the existence of moderate levels of genetic variability throughout Europe, although evidence of recent evolutionary bottlenecks was found in some populations. Estimation of migration rates and approximate Bayesian computations highlighted the most likely phylogeographical scenario for the current distribution of little owl populations. 相似文献
50.
Monteiro DR Gorup LF Silva S Negri M de Camargo ER Oliveira R Barbosa DB Henriques M 《Biofouling》2011,27(7):711-719
The aim of this study was to evaluate the effect of silver nanoparticles (SN) against Candida albicans and Candida glabrata adhered cells and biofilms. SN (average diameter 5 nm) were synthesized by silver nitrate reduction with sodium citrate and stabilized with ammonia. Minimal inhibitory concentration (MIC) tests were performed for C. albicans (n = 2) and C. glabrata (n = 2) grown in suspension following the Clinical Laboratory Standards Institute microbroth dilution method. SN were applied to adhered cells (2 h) or biofilms (48 h) and after 24 h of contact their effect was assessed by enumeration of colony forming units (CFUs) and quantification of total biomass (by crystal violet staining). The MIC results showed that SN were fungicidal against all strains tested at very low concentrations (0.4-3.3 μg ml(-1)). Furthermore, SN were more effective in reducing biofilm biomass when applied to adhered cells (2 h) than to pre-formed biofilms (48 h), with the exception of C. glabrata ATCC, which in both cases showed a reduction ~90%. Regarding cell viability, SN were highly effective on adhered C. glabrata and respective biofilms. On C. albicans the effect was not so evident but there was also a reduction in the number of viable biofilm cells. In summary, SN may have the potential to be an effective alternative to conventional antifungal agents for future therapies in Candida-associated denture stomatitis. 相似文献