129 research outputs found
I rapporti tra Italia e Marocco nel XIX Secolo. Dall’Italia a Tangeri, da Tangeri all’Italia
No full textObiettivo del volume è analizzare le relazioni fra Italia e Marocco nell'Ottocento, mettendone in rilievo la rilevanza nella storia dei popoli mediterrane
Nuclear proteins and the onset of cell proliferation in root meristems of Pisum sativum: QP47 a novel acidic protein
No full textA protein named QP47 has been purified from quiescent nuclei of root meristems of Pisum sativum, and used to prepare a polyclonal antibody. Immunolocalization of this protein with fluorescent probes revealed a nuclear distribution of thread-like structures. However, the relationship between the distribution of QP47 immunofluorescence and the structural organization of the chromatin required further investigation. The decrease in content of this protein in the nuclei of embryo cells seems to be correlated with the transition from quiescence to proliferation. QP47 degradation seems to depend upon an increase in the state of its phosphorylation. This protein is not present in normally proliferating cells, or in cells whose cell proliferation has been arrested by starvation or differentiation. It is hypothesized that QP47 may be required specifically during the quiescent period for specific structural organization of the chromatin
Feasibility of organophosphorus pesticide screening in waters with a cholinesterase inhibition test
No full textSpatial arrangement of the fibres in developing and mature endocarp of Luffa cylindrica Roem.
No full textLuffa cylindrica bears peculiar pepo-like fruits, which are characterised by a fibrous endocarp. Mature endocarps, so far utilised as a "vegetable sponge", are the object of studies for packing devices. By means of scanning, flluorescence and confocal microscopes, we investigated the arrangement and composition of the fibres in Luffa endocarps at different developmental stages in order to explain their functional properties
Low concentration of LatB dramatically changes the microtubule organization and the timing of vegetative nucleus/generative cell entrance in tobacco pollen tubes
No full textLow concentration of LatB inhibits not only the actin polymerization, but also induces profound alteration of MT distribution in pollen tubes of Nicotiana tabacum. The short randomly oriented MTs in the apical and subapical regions, became organized as bundles forming subapical rings or basket-like structures, surrounding the apex. Moreover, the depolymerization of AFs in the cortical regions of the apex and subapical region affects the timing of entrance of the vegetative nucleus and generative cell into the pollen tube
Endocytic Pathways and Recycling in Growing Pollen Tubes
No full textPollen tube growth is based on transport of secretory vesicles into the apical region where they fuse with a small area of the plasma membrane. The amount of secretion greatly exceeds the quantity of membrane required for growth. Mechanisms of membrane retrieval have recently been demonstrated and partially characterized using FM (Fei Mao) dyes or charged nanogold. Both these probes reveal that clathrin-dependent and -independent endocytosis occur in pollen tubes and are involved in distinct degradation pathways and membrane recycling. Exocytosis, internalization and sorting of PM proteins/lipids depend on the integrity of the actin cytoskeleton and are involved in actin filament organization. However, some kinds of endocytic and exocytic processes occurring in the central area of the tip still need to be characterized. Analysis of secretion dynamics and data derived from endocytosis highlight the complexity of events occurring in the tip region and suggest a new model of pollen tube growth
Cyclin-dependent kinase-like proteins in pea nuclei: their presence and role in cell proliferation
No full textAlthough many putative cdk (cyclin-dependent kinase) homologue genes have been identified in higher plants, their function and involvement in cell proliferation are still unclear. In this work we investigated the presence and distribution of cdk-like proteins in root tip meristem nuclei at different germination times (before, during, and after the onset of cell proliferation) and in nuclei of differentiated leaves. Nuclear cdk-like proteins were found in the root meristem throughout seed germination with a higher amount in actively proliferating cells, but were not detected in differentiated leaf. Characterization of the detected pea cdk-like proteins by immunoblotting led to the identification of two specific principal proteins of 33.2 and 34 kDa with the cdk conserved motif PSTAIRE. The p33.2 protein was also recognized by the anti-human p33(cdk2) antibody, suggesting that the p33.2 and p34 proteins could be pea homologues of human p33(cdk2) and p34(cdk1), involved in the G(1)-S and G(2)-M transitions, respectively. Additional analysis of pea cdk protein localization has shown partial localization of these proteins at DNA replication sites during the G(1) to S transition. These microscopical and biochemical data support the hypothesis that, in pea nuclei as in mammals, many PSTAIRE-cdks are present with different functions related to cell proliferation, one of which is probably involved in the control of the G(1)-S transition
Clemente Onelli and the Promotion of the Creole loom: A Project of Development Between Art and Industry
No full textEl presente artículo analiza el rol del naturalista italiano Clemente Onelli en la difusión de la técnica del telar criollo. Interesado las cualidades técnicas y materiales del textil americano, Onelli elaboró un discurso teórico a través del cual vinculó sus características principales con elementos identitarios de la nacionalidad argentina. Onelli se volvió una figura híbrida en la que se conjugaron los roles del crítico, el coleccionista y el gestor: esta última faceta lo llevó a contribuir en la gestación de proyectos educativos e industriales en torno al textil criollo.This article analizes the role of the Italian naturalist Clemente Onelli in the diffusion process of the creole loom technique. Interested in the technical and material qualities of the American textile, Onelli elaborated a theoretical discourse to relate its principal characteristics with elements of the Argentine national identity. Onelli became a hybrid figure that put together the roles of the critic, the collector and the promoter: this last aspect led him to make a contribution to the educational and industrial projects about the creole textile that were developed during the Twentieth century.Fil: Mantovani, Larisa Antonela. Universidad Nacional de San Martin. Centro de Investigaciones En Arte y Patrimonio. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Centro de Investigaciones En Arte y Patrimonio.; ArgentinaFil: Fasce, Pablo Javier. Universidad de Buenos Aires. Facultad de Filosofía y Letras; Argentina. Universidad Nacional de San Martín. Instituto de Altos Estudios Sociales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
- …
