Feijoa sellowiana derived natural Flavone exerts anti-cancer action displaying HDAC inhibitory activities

Curative properties of some medicinal plants such as the Feijoa sellowiana Bert. (Myrtaceae), have been often claimed, although the corresponding molecular mechanism(s) remain elusive. We report here that the Feijoa acetonic extract exerts anti-cancer activities on solid and hematological cancer cells. Feijoa extract did not show toxic effects on normal myeloid progenitors thus displaying a tumor-selective activity. In the Feijoa acetonic extract, fractionation and subsequent purification and analyses identified Flavone as the active component. Flavone induces apoptosis which is accompanied by caspase activation and p16, p21 and TRAIL over-expression in human myeloid leukemia cells. Use of ex vivo myeloid leukemia patients blasts confirms that both the full acetonic Feijoa extract and its derived Flavone are able to induce apoptosis. In both cell lines and myeloid leukemia patients blasts the apoptotic activity of Feijoa extract and Flavone is accompanied by increase of histone and non-histone acetylation levels and by HDAC inhibition. Our findings show for the first time that the Feijoa apoptotic active principle is the Flavone and that this activity correlates with the induction of HDAC inhibition, supporting the hypothesis of its epigenetic pro-apoptotic regulation in cancer systems.     

Repetitive DNA, molecular cytogenetics and genome organization in the King scallop (Pecten maximus)

We studied the structure, organization and relationship of repetitive DNA sequences in the genome of the scallop, Pecten maximus, a bivalve that is important both commercially and in marine ecology. Recombinant DNA libraries were constructed after partial digestion of genomic DNA from scallop with PstI and ApaI restriction enzymes. Clones containing repetitive DNA were selected by hybridisation to labelled DNA from scallop, oyster and mussel; colonies showing strong hybridisation only to scallop were selected for analysis and sequencing. Six non-homologous tandemly repeated sequences were identified in the sequences, and Southern hybridisation with all repeat families to genomic DNA digests showed characteristic ladders of hybridised bands. Three families had monomer lengths around 40 bp while three had repeats characteristic of the length wrapping around one (170 bp), or two (326 bp) nucleosomes. In situ hybridisation to interphase nuclei showed each family had characteristic numbers of clusters indicating contrasting arrangements. Two of the repeats had unusual repetitions of bases within their sequence, which may relate to the nature of microsatellites reported in bivalves. The study of these rapidly evolving sequences is valuable to understand an important source of genomic diversity, has the potential to provide useful markers for population studies and gives a route to identify mechanisms of DNA sequence evolution.     

Caloric restrictions affect some factors involved in age-related hypercholesterolemia

Ageing has been defined as a progressive decrease in physiological capacity and a reduced ability to respond to environmental stresses. It has been observed that diet-restricted animals show a minor morbidity in age-related disease. Among these age-related diseases, hypercholesterolemia is the most recurring one and it is often associated with cardiac failure. Several studies have been published indicating age-dependent changes in circulating levels of cholesterol in both humans and in rodents; recently changes have also been reported in the proteins involved in cholesterol homeostasis, that is, 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoAR), Insig-induced gene (Insig) protein, SREBP cleavage activating protein (SCAP), sterol regulatory element binding protein (SREBP), and low density lipoprotein receptor (LDLr). Most age-related modifications of biochemical parameters are normalized or very improved in food-restricted animals, so the aim of this work is to examine whether or not alterations of the factors involved in cholesterol homeostasis which occur during ageing could be counteracted by caloric restriction (CR). The data show that the diet restrictions used attenuate the age-related effects on the factors involved in the synthesis and the degradation rate of HMG-CoAR; in spite of this, CRs have a good effect on the age-related hypercholesterolemia whose reduction seems to depend both on the correct membrane LDLr localization and on the proper restored HMG-CoAR activity.     

Absorption flattening as one cause of distortion of circular dichroism spectra of Delta-RuPhen3 . H2TPPS complex

To extend the model that explains why and how much absorption flattening (AF) influences circular dichroism (CD) signals, we have investigated the interesting case of exciton CD in the Soret region of a noncovalent complex formed by (Delta-RuPhen(3))(2+) and the tetraanionic porphyrin H(2)TPPS. Different concentrations have been studied by using an AF emulator and spectra simulation. The CD spectra of this compound occasionally show distortions in the solution sampling mode with the increase of concentration; the inhomogeneous distribution in the cell volume is due to aggregation and is the source of the AF effect. On the basis of these results, we conclude that AF is an important cause of distortions in CD spectra for Delta-RuPhen(3) . H(2)TPPS complexes and might affect the CD bands of other aggregated systems as well.     

Evidence for strong genetic structure in European populations of the little owl Athene noctua

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.     

Long-distance dispersal of a wolf, <Emphasis Type="Italic">Canis lupus</Emphasis>, in northwestern Europe

Several mammal species have recolonized their historical ranges across Europe during the last decades. In November 2012, a wolf-looking canid was found dead in Thy National Park (56° 56′ N, 8° 25′ E) in Jutland, Denmark. DNA from this individual and nine German wolves were genotyped using a genome-wide panel of 22,163 canine single nucleotide polymorphism (SNP) markers and compared to existing profiles based on the same marker panel obtained from northeastern Polish (n?=?13) wolves, domestic dogs (n?=?13) and known wolf-dog hybrids (n?=?4). The Thy canid was confirmed to be a wolf from the German-western Polish population, approximately 800 km to the southeast. Access to the German reference database on DNA profiles based on 13 autosomal microsatellites of German wolves made it possible to pinpoint the exact pack origin of the Thy wolf in Saxony, Germany. This was the first documented observation of a wolf in Denmark in 200 years and another example of long-distance dispersal of a carnivore.     

Carbohydrate metabolism before and after dehiscence in the recalcitrant pollen of pumpkin (Cucurbita pepo L.)

Pumpkin (Cucurbita pepo L.) pollen is starchy, sucrose‐poor and recalcitrant, features opposite to those of several model species; therefore, some differences in carbohydrate metabolism could be expected in this species. By studying pumpkin recalcitrant pollen, the objective was to provide new biochemical evidence to improve understanding of how carbohydrate metabolism might be involved in pollen functioning in advanced stages. Four stages were analysed: immature pollen from 1 day before anthesis, mature pollen, mature pollen exposed to the environment for 7 h, and pollen rehydrated in a culture medium. Pollen viability, water and carbohydrate content and activity of enzymes involved in carbohydrate metabolism were quantified in each stage. Pollen viability and water content dropped quickly after dehiscence, as expected. The slight changes in carbohydrate concentration and enzyme activity during pollen maturation contrast with major changes recorded with ageing and rehydration. Pumpkin pollen seems highly active and closely related to its surrounding environment in all the stages analysed; the latter is particularly evident among insoluble sucrolytic enzymes, mainly wall‐bound acid invertase, which would be the most relevant for sucrose cleavage. Each stage was characterised by a particular metabolic/enzymatic profile; some particular features, such as the minor changes during maturation, fast sucrolysis upon rehydration or sharp decrease in insoluble sucrolytic activity with ageing seem to be related to the lack of dormancy and recalcitrant nature of pumpkin pollen.     

Experimental methods for measuring optical rotatory dispersion: survey and outlook

The measurement of optical rotation (OR) and optical rotatory dispersion has been finding renewed interest for some years, because of advancement in computational methods and in the performance of new experiments. Here, we shortly review the traditional and most-used experimental methods. We define and discuss the two main types of approaches in measuring OR: the intensity method and the optical null method. We report on some new results obtained by redesigning experiments based on the first approach, by adapting nonsophisticated hardware to current circular dichroism instrumentation.