Leaf and stem anatomy in eight Hypericum species (Clusiaceae)

Foliar micromorphology, epicuticular wax morphology and anatomical featuresof leaves and stem, particularly secondary xylem, were examined with light microscopy,general and histochemical staining and scanning electron microscopy in eightHypericum species. Outer tegument tissue and type of secondary xylem are determiningcharacteristics. Secondary xylem is ring-porous in H. perforatum, H. perfoliatum, H. tetrapterum, H. triquetrifolium, H. androsaemum and H. hircinum. In H. aegypticum and H. pubescens xylem is diffuse-porous, which is considered to be a more primitive type.These characteristics may be considered an additional criterion for species identification

Leukocyte, Rather than Tumor-produced SPARC, Determines Stroma and Collagen Type IV Deposition in Mammary Carcinoma

Secreted protein, acidic and rich in cysteine (SPARC), also known as osteonectin or BM-40, is a Ca2+-binding matricellular glycoprotein involved in development, wound healing, and neoplasia. However, the role of SPARC in tumors is ill defined mostly because it is expressed by both tumor and stromal cells, especially inflammatory cells. We analyzed the respective roles of host- and tumor-derived SPARC in wild-type and congenic SPARC knockout (SPARC−/−) mice on a BALB/c genetic background injected into the mammary fat pad with SPARC-producing mammary carcinoma cells derived from c-erB2 transgenic BALB/c mice. Reduced tumor growth but massive parenchyma infiltration, with large areas of necrosis and impaired vascularization were observed in SPARC−/− mice. Immunohistochemical analysis showed a defect in collagen type IV deposition in the stroma of lobular tumors from SPARC−/− mice. Chimeric mice expressing SPARC only in bone marrow–derived cells were able to organize peritumoral and perilobular stroma, whereas reciprocal chimeras transplanted with bone marrow from SPARC−/− mice developed tumors with less defined lobular structures, lacking assembled collagen type IV and with a parenchyma heavily infiltrated by leukocytes. Together, the data indicate that SPARC produced by host leukocytes, rather than the tumor, determines the assembly and function of tumor-associated stroma through the organization of collagen type IV

Comparative leaf micromorphology, anatomy and architecture in some Mediterranean species of Pancratium (Amaryllidaceae)

Leaves in Pancratium show a gross morphological identity. Difference at macroscopic level also regards leaf tip (acute to obtuse) and lamina width. Despite such uniformity of the leaf visible traits, micro-morphological and anatomical characteristics reveal significant variation both at intra-specific and inter-specific levels, which have proven to strongly depend on adaptation to microclimatic and ecological local conditions, such as temperature, water availability, insolation. Here we present preliminary results of a comparative morpho-anatomical study on leaves of some species of Pancratium (P. foetidum Pomel, P. illyricum L., P. linosae Soldano & F. Conti, P. maritimum L., P. sickenbergeri Boiss.) to assess the range of inter-specific variation, as well as population similarity or dissimilarity related to ecological adaptation

X-ray emission from stellar jets by collision against high-density molecular clouds: an application to HH 248

We investigate the plausibility of detecting X-ray emission from a stellar jet that impacts against a dense molecular cloud. This scenario may be usual for classical T Tauri stars with jets in dense star-forming complexes. We first model the impact of a jet against a dense cloud by 2D axisymmetric hydrodynamic simulations, exploring different configurations of the ambient environment. Then, we compare our results with XMM-Newton observations of the Herbig-Haro object HH 248, where extended X-ray emission aligned with the optical knots is detected at the edge of the nearby IC 434 cloud. Our simulations show that a jet can produce plasma with temperatures up to 10 MK, consistent with production of X-ray emission, after impacting a dense cloud. We find that jets denser than the ambient medium but less dense than the cloud produce detectable X-ray emission only at the impact onto the cloud. From the exploration of the model parameter space, we constrain the physical conditions (jet density and velocity, cloud density) that reproduce well the intrinsic luminosity and emission measure of the X-ray source possibly associated with HH 248. Thus, we suggest that the extended X-ray source close to HH 248 corresponds to the jet impacting on a dense cloud.Comment: Accepted for publication in ApJ. (12 pages, 12 figures

Dianthus borbonicus (Caryophyllaceae), a new species from Sicily

Dianthus borbonicus a new species occurring in North-Western Sicily is described and illustrated. It is a rare chasmophyte belonging to the D. sylvestris group, which is exclusive of a rupestrian stand near Rocca Busambra (Ficuzza). Its macro- and micromorphological features (seed testa sculptures, and leaf anatomy), ecology, conservation status and a comparison with the related species are provided too

Aggiornamenti e novità sulle conoscenze di Pancratium maritimum (Amaryllidaceae)

Pancratium maritimum L., bulbosa perenne degli ambienti dunali costieri, è un taxon relativamente recente se comparato con le specie del genere a gravitazione mediterranea. Gli studi noti su questa specie hanno analizzato vari aspetti della biologia (riproduttivi, biochimici, filogenetici, genetici, ecc.). Tuttavia, esistono ancora lacune scientifiche, tra cui l’assenza di studi su ampio areale di genetica di conservazione e sugli adattamenti eco-morfofisiologici alle condizioni di stress. Per ampliare le conoscenze su P. maritimum, la Fondazione Nando Peretti nel novembre 2012 ha finanziato un progetto triennale sulla conoscenza e la salvaguardia di questa specie (Progetto 2012-83). In questo contributo si presentano i risultati ottenuti per le diverse linee di ricerca finora affrontate, che vanno dalle analisi ad ampio areale dei popolamenti, usando un approccio sia genetico che GIS, alla caratterizzazione morfologica e eco-fisiologica di varie popolazioni

Hyperthermic superparamagnetic nanoparticles modulate adipocyte metabolism

Adipocytes are the principal cellular component in adipose tissue and their excessive hyperplasia or hypertrophy is actively involved in regulating physiologic and pathologic processes such as inflammation, cardiovascular disease, obesity and tumour. The main depot of energy in adipocytes is represented by lipid droplets, intracellular organelles that play fundamental roles in regulation of metabolic processes. An accumulation of such droplets could be a potential biomarker of disease caused by metabolic dysregulation. Recent studies have demonstrated that heat shock is associated with alteration in energy metabolism: the aim of this study is to modulate the energy metabolism of the adipocytes via controlled administration of thermal energy to reduce the number of lipid droplets. We have investigated the effect of controlled heating of adipocytes using an alternating magnetic field (AMF) on samples loaded with superparamagnetic nanoparticles (MNP) as heating agent