1,721,121 research outputs found
The hall of Protistology at the Museo di Storia Naturale e del Territorio di Pisa: developments and correlated initiatives.
No full textThe educational exhibition hall of Protistology, which opened in 2011 at the Museo di Storia Naturale e del Territorio di Pisa and actually the first in Italy, is regularly included in the teaching offer, scheduled annually by the museum itself. During the year, about 15 classes of children school of the Pisa’s district for a total of about 350 students have attended the educational courses related to the hall and entitled “Microcosm of a water drop” for the Primary School, and “Discovering the eukaryotic microorganisms” for the Secondary School. The educational visits, lasting about an hour and a half each, were coordinated by the Museum staff trained and generally composed of young graduates in Biological Sciences or Natural Sciences. Each educational trail was organized in such a way as to provide, in an appropriate language to the level of acquisition to the interested users, the necessary tools to develop the scientific and application knowledge on the importance of protists in various fields, from the environment to the health. In satisfaction questionnaires distributed to the completion of the courses, participating teachers have expressed very favorable opinions regarding to the discussion of the topics, the clarity of objectives consistent with the contents, the acquisition of new knowledge and the professionalism of the speakers. The answers of the students involved have confirmed that it is widespread in children's interest to work experimentally, suggesting the need to include new contents, such as the preparation of slides for observation under the optical microscope and the DNA extraction from protist cultures. The museum hall of Protistology was also involved in various initiatives of scientific-informative character, such as “II Congresso La ricerca scientifica in Museo, quale la realtà toscana?”, “Amico museo 2012”, “Calci ...in festa 2012”, “Campi solari CUS Pisa”, “Pianeta Galileo 2012”
Seasonal variations of glycogen synthase and phosphorylase activities in the liver of the frog Rana esculenta
No full textGlycogen metabolism has been studied in the liver of the frog Rana esculenta throughout the annual cycle. Hepatic glycogen reserves are high during winter and decrease during spring and summer, the changes being reflected by variations in the activities of the rate-limiting enzymes glycogen synthase and phosphorylase. Glycogen deposition is associated with increased levels of synthase D activity and no changes in the relative proportions of the active-inactive form of the enzyme, whereas during glycogen mobilization significant changes in both total phosphorylase and in the percent phosphorylase a are observed. Regression analysis indicates a positive correlation between glycogen content and synthase activity, and an inverse relationship between glycogen content and either total phosphorylase or phosphorylase a. The results suggest that glycogen deposition and/or mobilization could be mainly controlled by mechanisms related to either changes in the amount of enzyme protein or to allosteric effects of the metabolite glucose-6-phosphate on glycogen synthase and phorphorylase
Glycogen phosphorylase activity in the liver of the frog Rana esculenta
No full text1. Phosphorylase activity has been assayed in liver extracts of the frog, Rana esculenta, during the winter period. In native conditions, most of the phosphorylase is present as AMP-independent activity and shows properties similar to those of the a form of the liver enzyme from other vertebrates.
2. It is suggested that regulation of phosphorylase activity is through interconversion between a and b forms operated by endogenous phosphorylase kinase and phosphatase.
3. Kinetic studies show hyperbolic saturation curves for glycogen with apparent K(m) of 2.91 mM and 9.67 mM for a and b forms, respectively.
4. A hyperbolic saturation curve is also observed for glucose I-P in the case of phosphorylase a, with an apparent K(m) of 3.95 mM, whereas a sigmoidal kinetic is shown by the b form for the same substrate; from Hill plots an S0.5 of 24.2 mM was derived.
5. Hyperbolic responses were observed in the case of AMP, and K(a) of 70 muM and 0. 31 mM were calculated for phosphorylase a and b, respectively
Monitoraggio molecolare delle piante marine sottoposte ad impatto ambientale di origine antropica
No full textPossible role of Acanthamoeba polyphaga in Human Adenovirus protection against water chemical disinfection
Full text linkPheromone signalling in Euplotes raikovi: expression and ligand-stimulated internalization of the membrane-bound pheromone isoforms
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