Industrial Scale Isolation,Structural and Spectroscopic Characterization of Epiisopiloturine from Pilocarpus microphyllus Stapf Leaves: A Promising Alkaloid against Schistosomiasis

This paper presents an industrial scale process for extraction, purification, and isolation of epiisopiloturine (EPI) (2(3H)-Furanone,dihydro-3-(hydroxyphenylmethyl)-4-[(1-methyl-1H-imidazol-4-yl)methyl]-, [3S-[3a(R*),4b]]), which is an alkaloid from jaborandi leaves (Pilocarpus microphyllus Stapf). Additionally for the first time a set of structural and spectroscopic techniques were used to characterize this alkaloid. EPI has shown schistomicidal activity against adults and young forms, as well as the reduction of the egg laying adult worms and low toxicity to mammalian cells (in vitro). At first, the extraction of EPI was done with toluene and methylene chloride to obtain a solution that was alkalinized with ammonium carbonate. The remaining solution was treated in sequence by acidification, filtration and alkalinization. These industrial procedures are necessary in order to remove impurities and subsequent application of the high performance liquid chromatography (HPLC). The HPLC was employed also to remove other alkaloids, to obtain EPI purity higher than 98%. The viability of the method was confirmed through HPLC and electrospray mass spectrometry, that yielded a pseudo molecular ion of m/z equal to 287.1 Da. EPI structure was characterized by single crystal X-ray diffraction (XRD), ¹H and ¹³C nuclear magnetic resonance (NMR) in deuterated methanol/chloroform solution, vibrational spectroscopy and mass coupled thermal analyses. EPI molecule presents a parallel alignment of the benzene and the methyl imidazol ring separated by an interplanar spacing of 3.758 Å indicating a π-π bond interaction. The imidazole alkaloid melts at 225°C and decomposes above 230°C under air. EPI structure was used in theoretical Density Functional Theory calculations, considering the single crystal XRD data in order to simulate the NMR, infrared and Raman spectra of the molecule, and performs the signals attribution.     

Loss and rescue of osteocalcin and osteopontin modulate osteogenic and angiogenic features of mesenchymal stem/stromal cells

Noncollagenous proteins in the bone extracellular matrix, such as osteocalcin (OC) and osteopontin (OPN), inherent to evolution of bone as a skeletal tissue, are known to regulate bone formation and mineralization. However, the fundamental basis of this regulatory role remains unknown. Here, for the first time, we use mouse mesenchymal stem/stromal cells (MSC) lacking both OC and OPN to investigate the mechanistic roles of OC and OPN on the proliferation capacity and differentiation ability of MSC. We found that the loss of OC and OPN reduces stem cells self-renewal potential and multipotency, affects their differentiation into an osteogenic lineage, and impairs their angiogenic potential while maintaining chondrogenic and adipogenic lineages. Moreover, loss of OC and OPN compromises the extracellular matrix integrity and maturation, observed by an unexpected enhancement of glycosaminoglycans content that are associated with a more primitive skeletal connective tissue, and by a delay on the maturation of mineral species produced. Interestingly, exogenously supplemented OC and OPN were able to rescue MSC proliferative and osteogenic potential along with matrix integrity and mineral quality. Taken together, these results highlight the key contributions of OC and OPN in enhancing osteogenesis and angiogenesis over primitive connective tissue, and support a potential therapeutic approach based on their exogenous supplementation.     

Species delimitation based on integrative approach suggests reallocation of genus in Hypostomini catfish (Siluriformes,Loricariidae)

Hydrobiologia - Integrative approaches are particularly useful to resolve taxonomic uncertainties in species-rich groups that have undergone explosive radiation, such as Hypostomini (suckermouth...     

Model membranes to shed light on the biochemical and physical properties of ezrin/radixin/moesin

Ezrin, radixin and moesin (ERM) proteins are more and more recognized to play a key role in a large number of important physiological processes such as morphogenesis, cancer metastasis and virus infection. Recent reviews extensively discuss their biological functions 1, 2, 3 and 4. In this review, we will first remind the main features of this family of proteins, which are known as linkers and regulators of plasma membrane/cytoskeleton linkage. We will then briefly review their implication in pathological processes such as cancer and viral infection. In a second part, we will focus on biochemical and biophysical approaches to study ERM interaction with lipid membranes and conformational change in well-defined environments. In vitro studies using biomimetic lipid membranes, especially large unilamellar vesicles (LUVs), giant unilamellar vesicles (GUVs) and supported lipid bilayers (SLBs) and recombinant proteins help to understand the molecular mechanism of conformational activation of ERM proteins. These tools are aimed to decorticate the different steps of the interaction, to simplify the experiments performed in vivo in much more complex biological environments.     

Development of secondary sexual characters in the seabob shrimp Xiphopenaeus kroyeri (Heller 1862) (Crustacea,Decapoda, Penaeidae): a scanning electron microscope study

The development of secondary sexual characters, the petasma, and thelycum growth were studied in Xiphopenaeus kroyeri. In adult females, the thelycum is a single plate and its anterolateral portion is characterized by a reduced hood. The aperture resembles a transverse ridge. In immature stages, the ridge has a space between the plates, which becomes narrower as it reaches the end of development. The female gonopore is ‘comma’ shaped. In adult males, the endopods of the petasma are linked at the dorsomedial margin by a large quantity of cincinnuli. In juveniles, cincinnuli gradually increase in number until they join both endopods. At the end of development the petasma is T-shaped. The male gonopore is C-shaped. The relative growth of the petasma total length versus juvenile body length showed a highly positive allometry, whereas in adults the growth was isometric. For the relationship carapace length versus thelycum width, the juvenile phase of females is characterized by an isometry and the adult phase by a negative allometry.     

Update on the challenging role of biofilms in peritoneal dialysis

Biofilms are commonly associated with an increased risk of patient infection. In peritoneal dialysis (PD), catheter associated infection, especially peritonitis, remains a clinically relevant problem. Although the presence of a biofilm is recognized in relapsing, repeat, and catheter-related peritonitis, it remains poorly characterized. In this review, an update on the role of biofilms in PD infections is presented. The emerging concept that host cells and tissue associated biofilms, in addition to the biofilms on the catheters themselves, contribute to the recalcitrance of infections is discussed. Furthermore, the evidence of biofilms on PD catheters, their developmental stages, and the possible influence of the PD environment are reviewed. The focus is given to ex vivo and in vitro studies that contribute to the elucidation of the interplay between host, microbial, and dialysis factors. The key issues that are still to be answered and the challenges to clinical practice are discussed.     

Influence of Aloe vera on water absorption and enzymatic in vitro degradation of alginate hydrogel films

This study investigates the influence of Aloe vera on water absorption and the in vitro degradation rate of Aloe vera-Ca-alginate hydrogel films, for wound healing and drug delivery applications. The influence of A. vera content (5%, 15% and 25%, v/v) on water absorption was evaluated by the incubation of the films into a 0.1 M HCl solution (pH 1.0), acetate buffer (pH 5.5) and simulated body fluid solution (pH 7.4) during 24 h. Results show that the water absorption is significantly higher for films containing high A. vera contents (15% and 25%), while no significant differences are observed between the alginate neat film and the film with 5% of A. vera. The in vitro enzymatic degradation tests indicate that an increase in the A. vera content significantly enhances the degradation rate of the films. Control films, incubated in a simulated body fluid solution without enzymes, are resistant to the hydrolytic degradation, exhibiting reduced weight loss and maintaining its structural integrity. Results also show that the water absorption and the in vitro degradation rate of the films can be tailored by changing the A. vera content.     

Habitat selection for resting sites by the water opossum (Chironectes minimus) in the Brazilian Atlantic Forest

We evaluated the selection of resting sites occupied by the water opossum Chironectes minimus, between 2004 and 2010, in streams of the Brazilian Atlantic Forest. Fourteen radio-tracked adult (males and females) opossums used natural cavities as resting sites. Opossums selected narrow river stretches and selected their resting sites mainly according to characteristics favoring protection against adverse weather conditions. Likewise, opossums avoided disturbed habitats and established their resting sites in well-preserved riparian forest sites, selecting river sections containing a high density of trees and a high proportion of forest cover between the river banks and 50 m from the river. Besides increasing our knowledge on this species habitat selection, such findings further highlight this species’ sensitivity to human disturbance.     

Differential mortality of birds killed at wind farms in Northern Portugal

Capsule The Skylark Alauda arvensis had the highest overall mortality in ten Northern Portuguese wind farms surveyed between 2006 and 2011. Analysis from the integration of conventional and molecular techniques suggest a sex and age biased mortality affecting mainly adult males (90.9%), which may be related to their characteristic breeding male song-flights making them highly vulnerable to collision with wind turbines. The results highlight the added value of more complete population impact assessments that go beyond simple carcass identification at wind farms.