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91.
Dolci LS Marzocchi E Montalti M Prodi L Monti D Di Natale C D'Amico A Paolesse R 《Biosensors & bioelectronics》2006,22(3):399-404
Deposition of amphiphilic porphyrin derivatives occurs spontaneously on silanised glass surfaces, in a controlled fashion. The resulting porphyrin films show appreciable fluorescence emission. This emission can be effectively quenched by immersion of the slides into a diluted solution of Hg(2+) (microM concentration). The initial intensity can be restored by washings with a solution of N,N,N',N'-tetrakis(2-pyridilmethyl)ethylenediammine with no loss of efficiency. A remarkable selectivity is featured toward the detection of Hg(2+) over Cu(2+), Cd(2+), Pb(2+) and Zn(2+) counterparts. This protocol can be extended to a flow-through apparatus. The presented results are of importance for the achievement of a solid-state chemosensor for mercuric ions, at micromolar concentration, in water. 相似文献
92.
93.
Louise Solveig Nørgaard Dorthe Marlene Götz Mikkelsen Morten Elmeros Mariann Chriél Aksel Bo Madsen Jeppe Lund Nielsen Cino Pertoldi Ettore Randi Joerns Fickel Slaska Brygida Aritz Ruiz-González 《Biological invasions》2017,19(5):1637-1652
The raccoon dog (Nyctereutes procyonoides) has a wide distribution in Europe and is a prominent example of a highly adaptable alien species. It has been recorded sporadically in Denmark since 1980 but observations since 2008 suggested that the species had established a free-ranging, self-sustaining population. To elucidate the origin and genetic patterns of Danish raccoon dogs, we studied the population genomics of 190 individuals collected in Denmark (n = 141) together with reference captive individuals from Poland (n = 21) and feral individuals from different European localities (Germany, Poland, Estonia and Finland, n = 28). We used a novel genotyping-by-sequencing approach simultaneously identifying and genotyping a large panel of single nucleotide polymorphisms (n = 4526). Overall, there was significant indication for contemporary genetic structuring of the analysed raccoon dog populations, into at least four different clusters, in spite of the existence of long distance gene flow and secondary admixture from different population sources. The Danish population was characterized by a high level of genetic admixture with neighbouring feral European ancestries and the presence of private clusters, non-retrieved in any other feral or captive populations sampled. These results suggested that the raccoon dog population in Denmark was founded by escapees from genetically unidentified Danish captive stocks, followed by a recent admixture with individuals migrating from neighbouring Germany. 相似文献
94.
Wolf population genetics in Europe: a systematic review,meta‐analysis and suggestions for conservation and management
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Maris Hindrikson Jaanus Remm Malgorzata Pilot Raquel Godinho Astrid Vik Stronen Laima Baltrūnaité Sylwia D. Czarnomska Jennifer A. Leonard Ettore Randi Carsten Nowak Mikael Åkesson José Vicente López‐Bao Francisco Álvares Luis Llaneza Jorge Echegaray Carles Vilà Janis Ozolins Dainis Rungis Jouni Aspi Ladislav Paule Tomaž Skrbinšek Urmas Saarma 《Biological reviews of the Cambridge Philosophical Society》2017,92(3):1601-1629
The grey wolf (Canis lupus) is an iconic large carnivore that has increasingly been recognized as an apex predator with intrinsic value and a keystone species. However, wolves have also long represented a primary source of human–carnivore conflict, which has led to long‐term persecution of wolves, resulting in a significant decrease in their numbers, genetic diversity and gene flow between populations. For more effective protection and management of wolf populations in Europe, robust scientific evidence is crucial. This review serves as an analytical summary of the main findings from wolf population genetic studies in Europe, covering major studies from the ‘pre‐genomic era’ and the first insights of the ‘genomics era’. We analyse, summarize and discuss findings derived from analyses of three compartments of the mammalian genome with different inheritance modes: maternal (mitochondrial DNA), paternal (Y chromosome) and biparental [autosomal microsatellites and single nucleotide polymorphisms (SNPs)]. To describe large‐scale trends and patterns of genetic variation in European wolf populations, we conducted a meta‐analysis based on the results of previous microsatellite studies and also included new data, covering all 19 European countries for which wolf genetic information is available: Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Germany, Belarus, Russia, Italy, Croatia, Bulgaria, Bosnia and Herzegovina, Greece, Spain and Portugal. We compared different indices of genetic diversity in wolf populations and found a significant spatial trend in heterozygosity across Europe from south‐west (lowest genetic diversity) to north‐east (highest). The range of spatial autocorrelation calculated on the basis of three characteristics of genetic diversity was 650?850 km, suggesting that the genetic diversity of a given wolf population can be influenced by populations up to 850 km away. As an important outcome of this synthesis, we discuss the most pressing issues threatening wolf populations in Europe, highlight important gaps in current knowledge, suggest solutions to overcome these limitations, and provide recommendations for science‐based wolf conservation and management at regional and Europe‐wide scales. 相似文献
95.
Pokorná M Giovannotti M Kratochvíl L Kasai F Trifonov VA O'Brien PC Caputo V Olmo E Ferguson-Smith MA Rens W 《Chromosoma》2011,120(5):455-468
The divergence of lineages leading to extant squamate reptiles (lizards, snakes, and amphisbaenians) and birds occurred about
275 million years ago. Birds, unlike squamates, have karyotypes that are typified by the presence of a number of very small
chromosomes. Hence, a number of chromosome rearrangements might be expected between bird and squamate genomes. We used chromosome-specific
DNA from flow-sorted chicken (Gallus gallus) Z sex chromosomes as a probe in cross-species hybridization to metaphase spreads of 28 species from 17 families representing
most main squamate lineages and single species of crocodiles and turtles. In all but one case, the Z chromosome was conserved
intact despite very ancient divergence of sauropsid lineages. Furthermore, the probe painted an autosomal region in seven
species from our sample with characterized sex chromosomes, and this provides evidence against an ancestral avian-like system
of sex determination in Squamata. The avian Z chromosome synteny is, therefore, conserved albeit it is not a sex chromosome
in these squamate species. 相似文献
96.
Ettore RANDI 《Mammal Review》2011,41(2):99-111
- 1 The wolf Canis lupus, the most widespread of the four species of large carnivores in Europe, after centuries of population decline and eradication, is now recovering in many countries. Wolves contribute to regulating prey–predator dynamics and interact with human activities, mainly livestock farming and ungulate hunting. Although wolves are protected in most European countries, illegal or incidental killing is widespread.
- 2 Wolf populations do not show any apparent phylogeographic structuring worldwide. Molecular and morphological studies of historical samples showed evidence of wolf ecomorph extinctions, coinciding with the great Pleistocene faunal turnover.
- 3 Extant populations show recurrent long‐range dispersal during cycles of expansion and recolonization. Demographically stable populations, in contrast, seem to be characterized by very limited gene flow.
- 4 Despite the potential for dispersal and ecological flexibility, landscape genetic approaches have demonstrated the existence of genetically distinct wolf populations, which originated through habitat and prey specializations.
- 5 Small isolated wolf populations may suffer from inbreeding depression, although selection for heterozygotes and the rescue effect can foster rapid population recovery. Population structure and dynamics is efficiently monitored by non‐invasive genetic methods, which are also useful to identify wolf × dogCanis lupus familiaris hybridization.
- 6 Despite technical advances and a better knowledge of wolf biology, wolf conservation is largely dependent on humans, and on the solution of conflicts with stakeholders.
97.
Adriano Sofo Antonio Scopa Michele Manfra Mauro De Nisco Giancarlo Tenore Jacopo Troisi Raffaele Di Fiori Ettore Novellino 《Plant Growth Regulation》2011,65(2):421-425
The aim of this research was to explain the direct plant growth-promoting activity of Trichoderma harzianum strain T-22 (T22), hypothesizing the involvement of different classes of plant growth regulators. Seven days after the transfer
to root-inducing medium, in vitro-cultured shoots of GiSeLa6? (Prunus cerasus × P. canescens) were inoculated with T22. Root and shoot growth were significantly affected by T22 (+76 and +61%, respectively). Ten days
after inoculation, the levels of indole-3-acetic acid (IAA), trans-zeatin riboside (t-ZR), dihydrozeatin riboside (DHZR), gibberellic acid (GA3) and abscisic acid (ABA) were analyzed by high performance liquid
chromatography coupled with mass spectrometry. The results showed that after T22-inoculation, IAA and GA3 significantly increased
in both leaves (+49 and +71%, respectively) and roots (+40 and +143%, respectively) whereas t-ZR decreased (−51% in leaves and −37% in roots). Changes in DHZR were observed in T22-inoculated roots (−32%) but not in
leaves, whereas the levels of ABA did not differ between the two treatments. The extraction method allowed the simultaneous
extraction of phytohormones. There is evidence that the change in phytohormone levels is one of the direct mechanism by which
T22 promotes rooting and shoot growth, with notable advantages for rootstock production during nursery processes. 相似文献
98.
Montecucco F Bertolotto M Vuilleumier N Franciosi U Puddu A Minetti S Delrio A Quercioli A Bergamini E Ottonello L Pende A Lenglet S Pelli G Mach F Dallegri F Viviani GL 《American journal of physiology. Endocrinology and metabolism》2011,300(4):E681-E690
Metabolic syndrome is a proatherosclerotic condition clustering cardiovascular risk factors, including glucose and lipid profile alterations. The pathophysiological mechanisms favoring atherosclerotic inflammation in the metabolic syndrome remain elusive. Here, we investigated the potential role of the antilipolytic drug acipimox on neutrophil- and monocyte-mediated inflammation in the metabolic syndrome. Acipimox (500 mg) was orally administered to metabolic syndrome patients (n = 11) or healthy controls (n = 8). Serum and plasma was collected before acipimox administration (time 0) as well as 2-5 h afterward to assess metabolic and hematologic parameters. In vitro, the effects of the incubation with metabolic syndrome serum were assessed on human neutrophil and monocyte migration toward the proatherosclerotic chemokine CCL3. Two to five hours after acipimox administration, a significant reduction in circulating levels of insulin and nonesterified fatty acid (NEFA) was shown in metabolic syndrome patients. At time 0 and 2 h after acipimox administration, metabolic syndrome serum increased neutrophil migration to CCL3 compared with healthy controls. No effect was shown in human monocytes. At these time points, serum-induced neutrophil migration positively correlated with serum levels of insulin and NEFA. Metabolic syndrome serum or recombinant insulin did not upregulate CCR5 expression on neutrophil surface membrane, but it increased intracellular JNK1/2 phosphorylation. Insulin immunodepletion blocked serum-induced neutrophil migration and associated JNK1/2 phosphorylation. Although mRNA expression of acipimox receptor (GPR109) was shown in human neutrophils, 5-500 μM acipimox did not affect insulin-induced neutrophil migration. In conclusion, results suggest that acipimox inhibited neutrophil proatherosclerotic functions in the metabolic syndrome through the reduction in circulating levels of insulin. 相似文献
99.
Grieco P Franco R Bozzuto G Toccacieli L Sgambato A Marra M Zappavigna S Migaldi M Rossi G Striano S Marra L Gallo L Cittadini A Botti G Novellino E Molinari A Budillon A Caraglia M 《Journal of cellular biochemistry》2011,112(1):341-353
Urotensin II (UT-II) is a potent vasoconstrictor peptide and its receptor (UTR) was correlated with human cortico-adrenal carcinoma proliferation. In this study, we have evaluated the correlation between UTR expression and prognosis of human prostate adenocarcinoma and the involvement of this receptor in the regulation of biological properties on both in vivo and in vitro models. UTR mRNA and protein, evaluated by real-time PCR and Western blotting, respectively, were expressed at high levels only in androgen-dependent LNCaP cells. In order to investigate UTR changes occurring in human prostate tumorigenesis, we have also evaluated the expression of UTR in vivo in 195 human prostate tissue samples. UTR was always expressed at low intensity in hyperplastic tissues and at high intensity in well-differentiated carcinomas (Gleason 2-3). Moreover, we have evaluated the effects of an antagonist of UTR, urantide on migration and invasion of LNCaP cells. Urantide induced a dose-dependent decrease of motility and invasion of LNCaP cells whose characteristic ameboid movement seems to be advantageous for their malignancy. These effects were paralleled by down-regulating the autophosphorylation of focal adhesion kinase and the integrin surface expression on LNCaP cells. The effects on cell motility and invasion were likely due to the inhibition of RhoA activity induced by both urantide and shRNA UTR. These data suggest that UTR can be considered a prognostic marker in human prostate adenocarcinoma patients. 相似文献
100.
Da Settimo F Primofiore G La Motta C Salerno S Novellino E Greco G Lavecchia A Laneri S Boldrini E 《Bioorganic & medicinal chemistry》2005,13(2):491-499
The 2,3-dihydrospiro[4H-thiopyrano[2,3-b]pyridin-4,4'-imidazolidine]-2',5'-dione 3 and its 7-methyl analogue 4 were synthesized and tested for their ability to inhibit aldose reductase (ALR2). To expand the structure-activity relationships, the sulfone 5 and the acetic acid derivative 7 were also prepared and tested. Compounds 3 and 4 proved to be potent ALR2 inhibitors, with IC50 values in the submicromolar range (0.96 and 0.94 microM, respectively) similar to that of sorbinil (0.65 microM). Moreover, compound 3 was found to be highly potent in preventing cataract development in severely galactosemic rats, like tolrestat, when administered as an eyedrop solution. Docking simulations of both R- and S-isomers of 3 into the ALR2 crystal structure were carried out to guide, prospectively, the design of new analogues. 相似文献