Nanoparticle drug delivery systems for inner ear therapy: An overview

open7noembargoed_20180701Valente, Filippo; Astolfi, Laura; Simoni, Edi; Danti, Serena; Franceschini, Valeria; Chicca, Milvia; Martini, AlessandroValente, Filippo; Astolfi, Laura; Simoni, Edi; Danti, Serena; Franceschini, Valeria; Chicca, Milvia; Martini, Alessandr

High Density Lipoproteins Inhibit Oxidative Stress-Induced Prostate Cancer Cell Proliferation

Recent evidence suggests that oxidative stress can play a role in the pathogenesis and the progression of prostate cancer (PCa). Reactive oxygen species (ROS) generation is higher in PCa cells compared to normal prostate epithelial cells and this increase is proportional to the aggressiveness of the phenotype. Since high density lipoproteins (HDL) are known to exert antioxidant activities, their ability to reduce ROS levels and the consequent impact on cell proliferation was tested in normal and PCa cell lines. HDL significantly reduced basal and H2O2-induced oxidative stress in normal, androgen receptor (AR)-positive and AR-null PCa cell lines. AR, scavenger receptor BI and ATP binding cassette G1 transporter were not involved. In addition, HDL completely blunted H2O2-induced increase of cell proliferation, through their capacity to prevent the H2O2-induced shift of cell cycle distribution from G0/G1 towards G2/M phase. Synthetic HDL, made of the two main components of plasma-derived HDL (apoA-I and phosphatidylcholine) and which are under clinical development as anti-atherosclerotic agents, retained the ability of HDL to inhibit ROS production in PCa cells. Collectively, HDL antioxidant activity limits cell proliferation induced by ROS in AR-positive and AR-null PCa cell lines, thus supporting a possible role of HDL against PCa progression

Age Structure and Feeding of the Neotropical Grasshopper Cornops aquaticum (Bruner) (Orthoptera: Acrididae) on Water Hyacinth.

We aimed to evaluate the variation in the age structure of Cornops aquaticum (Bruner) population and its relation to the host plant biomass and the feeding of the different age classes of this grasshopper on the Water Hyacinth Eichhornia crassipes along two years, in a Paraná River floodplain lake (Chaco, Argentina). Individuals of C. aquaticum were captured with a 70-cm diameter sweep and separated in nymphs A (instars I and II), nymphs B (instars III to VI), adult females and adult males; host plant biomass was sampled using a ring with a 0.30 m2 diameter. Relative daily feeding of C. aquaticum population was calculated by multiplying the number of individuals captured per minute by the daily consumption by individual obtained in each age classes. We found that the age structure and the relative daily feeding of C. aquaticum varied between seasons and years. The highest values of grasshopper abundance, leaf biomass and relative daily feeding of C. aquaticum population were observed in summer 2006. Plant biomass was directly correlated with nymph abundance and not correlated with adult abundance. Plant biomass available as refuge (leaves), food (laminas) and oviposition site (petioles) to C. aquaticum represented up to 62 % of the total plant biomass. The results obtained in C. aquaticum show the importance of considering total plant biomass and plant biomass available for herbivores separately. Our study highlights the need to find an adequate method to estimate density of C. aquaticum and other semi-aquatic grasshoppers in the Paraná River floodplain involving different seasons, years and water phases (rising and falling).Fil: Franceschini, Maria Celeste. Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Nordeste. Centro de Ecologia Aplicada del Litoral (i); Argentina;Fil: de Wysiecki, Maria Laura. Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - la Plata. Centro de Est.parasitol.y de Vectores (i); Argentina;Fil: Poi, Alicia Susana G.. Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Nordeste. Centro de Ecologia Aplicada del Litoral (i); Argentina

Regenerative medicine in hearing recovery

Hearing loss, or deafness, affects 360 million people worldwide of which about 32 million are children. Deafness is irreversible when it involves sensory hair cell death because the regenerative ability of these cells is lost in mammals after embryo development. The therapeutic strategies for deafness include hearing aids and/or implantable devices. However, not all patients are eligible or truly benefit from these medical devices. Regenerative medicine based on stem cell application could play a role in both improvement of extant medical devices and in vivo recovery of auditory function by regeneration of inner ear cells and neurons. A review of recent literature on the subject indicates that two promising approaches to renewal and differentiation of cochlear tissues are transplantation of stem cells and in situ administration of growth factors. Rather than directly regenerating dead cells, these procedures apparently induce, through various pathways, differentiation of resident cochlear cells. More studies on the possible adverse effects of transplanted cells and the recovery of tonotopic sensorineural activity or required. To date, no reliable clinical results have been obtained in the field of cochlear regeneration. \ua9 2017 International Society for Cellular Therapy

Early-Type Galaxies in the Hubble Deep Field: The Star Formation History

We have investigated the properties of a complete K-band selected sample of 35 elliptical and S0 galaxies brighter than K=20.15 in the Hubble Deep Field, as representative of the field galaxy population. This sample has been derived from deep K-band image by the KPNO-IRIM camera, by applying a rigorous morphological classification scheme based on quantitative analyses of the surface brightness profiles. The broad-band spectra of the sample galaxies allow us to date their dominant stellar populations. The majority of bright early-types in this field are found at redshifts z<1.3 to display colors indicative of a fairly wide range of ages (typically 1.5 to 3 Gyrs). We find that the major episodes of star-formation building up typical M_star galaxies have taken place during a wide redshift interval 11.3, which should be detectable during the luminous star-formation phase expected to happen at these redshifts. Obvious solutions are a) that the merging events imply perturbed morphologies which prevent selecting them by our morphological classification filter, or b) that a dust-polluted ISM obscures the (either continuous or episodic) events of star-formation. We conclude that the likely solution is a combination thereof, i.e. a set of dust-enshrouded merging-driven starbursts occurring during the first few Gyrs of the galaxy's lifetime

The role of the host-specific grasshopper <i>Cornops aquaticum</i> (Orthoptera: Acrididae) as consumer of native <i>Eichhornia crassipes</i> (Pontederiaceae) floating meadows

Cornops aquaticum is a widely distributed semiaquatic grasshopper in the Neotropics. The development, feeding and oviposition of C. aquaticum take place on Pontederiaceae, especially on species of Eichhornia. Several aspects of the feeding of C. aquaticum are studied because is one of the most important herbivores of the highly invasive floating Eichhornia crassipes in native areas. The aims of this paper were: (1) to quantify the amount of E. crassipes consumed by C. aquaticum, (2) to determine the growth rate and the conversion efficiency of food ingested by this grasshopper, and (3) to determine the possible effect of consumption on E. crassipes productivity. Thirty individuals from each specific age class were used in the experiment: nymphs A, nymphs B, adult males and adult females. Insects were individually confined in plastic pots with a leaf of E. crassipes. We estimated feeding by individual, consumption index (CI), relative growth rate (GR) and efficiency of conversion of ingested food to body substance (ECI). The impact of C. aquaticum consumption on E. crassipes floating meadows was assessed with the abundance of the grasshopper, and the available data on primary production of the host plant at the study site. Food intake of C. aquaticum was 11.23% of plant productivity. Food consumption, growth rate and food conversion efficiency of this grasshopper varied according to the specific age classes. Damage caused by C. aquaticum is high in comparison with the damage caused by other semiaquatic and grassland grasshoppers, however it is not enough to prevent the growth and coverage of native E. crassipes floating meadows because abundance of grasshoppers are realtively low and the growth rate and productivity of the host plant is high.Centro de Estudios Parasitológicos y de Vectore

Conditional Inactivation of Limbic Neuropeptide Y-1 Receptors Increases Vulnerability to Diet-Induced Obesity in Male Mice

NPY and its Y1 cognate receptor (Y1R) have been shown to be involved in the regulation of stress, anxiety, depression and energy homeostasis. We previously demonstrated that conditional knockout of Npy1r gene in the excitatory neurons of the forebrain of adolescent male mice (Npy1rrfb mice) decreased body weight growth and adipose tissue and increased anxiety. In the present study, we used the same conditional system to examine whether the targeted disruption of the Npy1r gene in limbic areas might affect susceptibility to obesity and associated disorders during adulthood in response to a 3-week high-fat diet (HFD) regimen. We demonstrated that following HFD exposure, Npy1rrfb male mice showed increased body weight, visceral adipose tissue, and blood glucose levels, hyperphagia and a dysregulation of calory intake as compared to control Npy1r2lox mice. These results suggest that low expression of Npy1r in limbic areas impairs habituation to high caloric food and causes high susceptibility to diet-induced obesity and glucose intolerance in male mice, uncovering a specific contribution of the limbic Npy1r gene in the dysregulation of the eating/satiety balance

Limited proteolysis of a disulfide-linked apoA-I dimer in reconstituted HDL.

The apolipoprotein A-I Milano (apoA-I M ) is a mo- lecular variant of apoA-I characterized by the Arg 173 → Cys substitution, leading to the formation of homodimers A-I M / A-I M. Upon interaction with palmitoyloleoylphosphatidyl- choline, A-I M /A-I M forms only two species of reconstituted HDL (rHDL) particles, with diameters of 7.8 and 12.5 nm. We used limited proteolysis to analyze the conformation of A-I M /A-I M in the two rHDL particles, in comparison with that of apoA-I in rHDL of similar size. ApoA-I in the small, 7.8-nm rHDL is degraded to a greater extent (50% after 6 h) than in the large rHDL ( � 10% degraded after 6 h). The pro- tease susceptibility of A-I M /A-I M in small and large rHDL is instead remarkably the same, with A-I M /A-I M being much more sensitive to proteolytic digestion (50% degraded after 10 min) than apoA-I. The identification of the proteolytic fragments by immunoblotting, N-terminal sequencing, and molecular mass determination, shows that the N-terminus of both proteins is resistant to proteolysis, with six cleavage sites located in the central and carboxy-terminal portions of the molecules. Cleavage in the middle of apoA-I occurs at dis- tinct sites in 7.8-nm (Lys 118 ) and 12.7-nm (Arg 123 ) rHDL, in- dicating a different conformation in small and large rHDL particles. The A-I M /A-I M instead adopts a unique and identi- cal conformation in small and large rHDL, with the carboxy- terminal portion of the molecule being remarkably more ac- cessible to the proteases than in apoA-I. This suggests the presence of a novel carboxy-terminal domain in A-I M /A-I M , not organized in a compact structure and not shared by wild-type apoA-I, which may account for the unique functional proper- ties of A-I M /A-I M. —Calabresi, L., G. Tedeschi, C. Treu, S. Ron- chi, D. Galbiati, S. Airoldi, C. R. Sirtori, Y. Marcel, and G. Franceschini. Limited proteolysis of a disulfide-linked apoA-I dimer in reconstituted HDL. J. Lipid Res. 2001. 42: 935-942

Impacts on freshwater macrophytes produced by small invertebrate herbivores:Afrotropical and Neotropical wetlands compared

We compare invertebrate herbivory upon 13 macrophyte species in freshwater wetland systems located in two global ecozones, the Afrotropics and Neotropics, in the context of biotic and environmental factors influencing these wetlands. The two ecozones are climatically similar regions, with similar water chemistry, but experience contrasting grazing and disturbance pressures from large mammalian herbivores. Our results for macrophytes show that small invertebrates removed significantly more lamina biomass per leaf in Neotropical macrophytes (6.55%) than Afrotropical ones (4.99%). Overall, the results indicate that underestimation of up to 15.6% of leaf biomass may occur if plant tissue removal by invertebrate herbivores is not included in estimates of plant biomass. Regarding the contrasting grazing and disturbance pressures from large herbivores influencing these wetlands, seven mammal species (especially the Black Lechwe antelope, Kobus leche) were observed impacting macrophytes in the Afrotropical wetlands, while in the Neotropics, only much smaller rodents, capybara, (Hydrochoerus hydrochaeris) were sporadically observed. We discuss the relevance of results for invertebrate herbivory in the context of both the methodological approach and the importance of large mammalian herbivores as biotic factors additionally impacting macrophyte populations in these subtropical to tropical wetlands.Fil: Franceschini, Maria Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Murphy, Kevin. University of Glasgow; Reino UnidoFil: Moore, Isabel. University of Glasgow; Reino UnidoFil: Kennedy, Michael P.. University of Aberdeen; Reino UnidoFil: Martínez, Fedra Solange. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Willems, Frank. Kasanka Trust - Kasanka National Park; ZambiaFil: de Wysiecki, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Sichingabula, Henry. University Of Zambia; Zambi