Contribution to the cytotaxonomical knowledge of four species of Serapias L. (Orchidaceae)

Abstract Serapias L. includes about thirty entities, but just one (S. lingua) is presently known as polyploid. In this paper we reported, for the first time, the chromosome number of S. gregaria, S. olbia and S. strictiflora, three endemic species of Southwest Europe, that resulted tetraploid with 2n = 72 chromosomes as S. lingua. The strong affinity between these four species revealed by molecular phylogenetic studies based on cpDNA is now supported by their common tetraploid level, so that polyploidy can be considered for this genus a possible mechanism of speciation. The karyotype of another endemic species of Iberian Peninsula, S. perezchiscanoi, was carried out in order to add new karyological data on Serapias orchids

Effects of human disturbance on reproductive success and population viability of<i>Serapias cordigera</i>(Orchidaceae)

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Molecular identification of mycorrhizal fungi in Dactylorhiza sambucina (Orchidaceae)

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New Insights into the Potential Roles of 3-Iodothyronamine (T1AM) and Newly Developed Thyronamine-Like TAAR1 Agonists in Neuroprotection

3-Iodothyronamine (T1AM) is an endogenous high-affinity ligand of the trace amine-associated receptor 1 (TAAR1), detected in mammals in many organs, including the brain. Recent evidence indicates that pharmacological TAAR1 activation may offer a novel therapeutic option for the treatment of a wide range of neuropsychiatric and metabolic disorders. To assess potential neuroprotection by TAAR1 agonists, in the present work, we initially investigated whether T1AM and its corresponding 3-methylbiaryl-methane analog SG-2 can improve learning and memory when systemically administered to mice at submicromolar doses, and whether these effects are modified under conditions of MAO inhibition by clorgyline. Our results revealed that when i.p. injected to mice, both T1AM and SG-2 produced memory-enhancing and hyperalgesic effects, while increasing ERK1/2 phosphorylation and expression of transcription factor c-fos. Notably, both compounds appeared to rely on the action of ubiquitous enzymes MAO to produce the corresponding oxidative metabolites that were then able to activate the histaminergic system. Since autophagy is key for neuronal plasticity, in a second line of experiments we explored whether T1AM and synthetic TAAR1 agonists SG1 and SG2 were able to induce autophagy in human glioblastoma cell lines (U-87MG). After treatment of U-87MG cells with 1 μM T1AM, SG-1, SG-2 transmission electron microscopy (TEM) and immunofluorescence (IF) showed a significant time-dependent increase of autophagy vacuoles and microtubule-associated protein 1 light chain 3 (LC3). Consistently, Western blot analysis revealed a significant increase of the LC3II/LC3I ratio, with T1AM and SG-1 being the most effective agents. A decreased level of the p62 protein was also observed after treatment with T1AM and SG-1, which confirms the efficacy of these compounds as autophagy inducers in U-87MG cells. In the process to dissect which pathway induces ATG, the effects of these compounds were evaluated on the PI3K-AKT-mTOR pathway. We found that 1 μM T1AM, SG-1 and SG-2 decreased pAKT/AKT ratio at 0.5 and 4 h after treatment, suggesting that autophagy is induced by inhibiting mTOR phosphorylation by PI3K-AKT-mTOR pathway. In conclusion, our study shows that T1AM and thyronamine-like derivatives SG-1 and SG-2 might represent valuable tools to therapeutically intervene with neurological disorder

Effect of oxygen contamination on densification of Fe(Se,Te)

Abstract The optimization of sintering behaviour of iron chalcogenides superconducting materials is mandatory to enhance their critical current density, in order to pursuit their application in the production of superconducting wires. In this context it has been investigated here the effect of oxygen contamination on the material densification, considering the issues related to industrial oxygen-free isolated production lines. Our results show that the densification process is negatively affected by oxygen contamination. However, despite the difference in density, all sintered samples are characterized by similar structural and morphological features, and show comparable electrical and magnetic properties, with low critical current densities (Jc<103 A/cm2). These results suggest that densification is not the key limiting factor in these conditions, and that grain boundary or misorientation factors may play a greater role in limiting the performance of sintered iron chalcogenides superconductors

Uniparental Genetic Heritage of Belarusians: Encounter of Rare Middle Eastern Matrilineages with a Central European Mitochondrial DNA Pool

Ethnic Belarusians make up more than 80% of the nine and half million people inhabiting the Republic of Belarus. Belarusians together with Ukrainians and Russians represent the East Slavic linguistic group, largest both in numbers and territory, inhabiting East Europe alongside Baltic-, Finno-Permic- and Turkic-speaking people. Till date, only a limited number of low resolution genetic studies have been performed on this population. Therefore, with the phylogeographic analysis of 565 Y-chromosomes and 267 mitochondrial DNAs from six well covered geographic sub-regions of Belarus we strove to complement the existing genetic profile of eastern Europeans. Our results reveal that around 80% of the paternal Belarusian gene pool is composed of R1a, I2a and N1c Y-chromosome haplogroups – a profile which is very similar to the two other eastern European populations – Ukrainians and Russians. The maternal Belarusian gene pool encompasses a full range of West Eurasian haplogroups and agrees well with the genetic structure of central-east European populations. Our data attest that latitudinal gradients characterize the variation of the uniparentally transmitted gene pools of modern Belarusians. In particular, the Y-chromosome reflects movements of people in central-east Europe, starting probably as early as the beginning of the Holocene. Furthermore, the matrilineal legacy of Belarusians retains two rare mitochondrial DNA haplogroups, N1a3 and N3, whose phylogeographies were explored in detail after de novo sequencing of 20 and 13 complete mitogenomes, respectively, from all over Eurasia. Our phylogeographic analyses reveal that two mitochondrial DNA lineages, N3 and N1a3, both of Middle Eastern origin, might mark distinct events of matrilineal gene flow to Europe: during the mid-Holocene period and around the Pleistocene-Holocene transition, respectively

Filogenesi e processi speciativi in orchidee Mediterranee non nettarifere del genere Serapias L.(Orchidaceae)

Dottorato di ricerca in Biologia Vegetale, XVIII Ciclo, a.a.2005-2006Università della Calabri

Preparation of albumin-ferrite superparamagnetic nanoparticles using reverse micelles

Micellar systems are widely applied as reactors to encapsulate inorganic nanoparticles in polymeric materials. However, only low inorganic contents and microscale dimensions are often achieved. The adsorption of albumin protein on ferrite nanoparticles permits to increase the stability of inorganic dispersions in water by inhibiting particle flocculation. Subsequent glutaraldehyde addition induces protein crosslinking and ferrite entrapment. Polymer–ferrite composite nanoparticles were obtained in this way. The magnetic albumin nanoparticles (25 nm mean diameter) obtained contain about 40wt% of ferrite and show superparamagnetic behaviour. The composite powder was successfully functionalized with amodel drug and the biological activity was evaluated

Comparative floral micromorphology in four sympatric species of Serapias (Orchidaceae)

A great variety of colours, shapes, scents, energy-rich rewards and other floral traits form an integrated system that increases pollination efficiency or reduces pollen loss. Flowers lacking energetic rewards possess a more elaborate morphology to ensure co-specific pollination. Despite the prevalence of deceptive species among Euro-Mediterranean orchids, the study of their floral micromorphology is still in its infancy. In this work, we examine the floral micromorphology of four sympatric species of the widespread Mediterranean genus Serapias. Electron microscopy (scanning, transmission) was performed on flowers of four sympatric species of the deceptive genus Serapias, the widespread S.cordigera, S.lingua, S.parviflora and S.vomeracea. Each species has a characteristic combination of specialized, secretory epidermal cells and trichomes on the labellum and, to a lesser extent, the petals. Serapias lingua is highly specialized in that it produces olfactory signals and has two types of trichome with secretory apical cells, one of which is also present in S.parviflora. In addition to striated, conical secretory cells, S.cordigera and S.vomeracea also have characteristic, atypical secretory trichomes with bilobulate or dome-like protuberances. The labellar micromorphology of S.lingua and S.parviflora is adapted for scent production, whereas S.vomeracea and S.cordigera possess trichomes that may also provide visual and/or tactile cues. Owing to the combined effect of the specific floral fragrance and labellar micromorphology in pollinator selection, the pollination ecology of Serapias spp. is even more specialized than previously thought. © 2012 The Linnean Society of London