3,058 research outputs found
Eudragit-coated albumin nanospheres carrying inclusion complexes for oral administration of indomethacin
No full textOral administration of indomethacin as well as drugs with low aqueous solubility usually results in poor absorption and bioavailability. The aim of this study was to prepare enteric-coated bovine serum albumin nanospheres carrying cyclodextrin complex for indomethacin delivery. Inclusion complex composed of indomethacin and β-cyclodextrin was prepared by spray-drying. Indomethacin alone and its inclusion complex were incorporated into albumin nanospheres using a coacervation method followed by thermal cross-linking. Then nanosphere suspensions were spray-dried. The inclusion complex and the nanospheres were characterized by FT-IR spectroscopy and DSC analysis. Phase-solubility diagrams and stability constants were determined at pH 2.0 and 7.4 and at different temperatures (10, 25 and 37°C). Swelling ability of nanospheres were evaluated as well as the in vitro release behaviour at pH 2.0 and 7.4. The nanospheres were coated with Eudragit L-100 or S-100 using spray-drying to give protection in the stomach. The results showed that indomethacin solubility can be increased by complexation with β-cyclodextrin or protein/drug interaction with albumin nanospheres. The inclusion complex loaded into BSA nanospheres provided a zero order drug release kinetic. The coating process with EudL and EudS allowed to obtain a negligible release at acidic pH without limit drug availability at pH 7.4
Omega-3 fatty acid and antioxidant enriched liposomes for nasal administration of anti-Alzheimer drugs
No full textThe purpose of this work was the formulation of
liposomes for nasal administration of tacrine·HCl. This
route has many advantages, in fact it is possible to convey
the drug directly to the CNS, through the olfactory bulb.
Part of tacrine administered can also be absorbed into the
systemic circulation avoiding hepatic first pass effect.
Liposomes were formulated with ingredients that have a
beneficial effect against the disease. In particular, the
cholesterol was replaced with α-tocopherol, and
phospholipids were enriched with polyunsaturated fatty
acids (DHA, EPA α-linolenic acid). This formulative
approach allowed us to obtain 100% active liposomes
against symptoms of Alzheimer's disease
Freeze-dried chitosan/pectin nasal inserts for antipsychotic drug delivery
No full textThe objective of this investigation was the development of chitosan/pectin based nasal inserts to improve
bioavailability of antipsychotic drugs in the treatment of psychotic symptoms. In fact, the nasal route of
administration ensures systemic availability avoiding the first-pass metabolism and obtaining more efficacious
treatments. Chitosan/pectin polyelectrolyte complexes were prepared at pH 5.0 with different
polycation/polyanion molar ratios and lyophilized in small inserts in the presence of chlorpromazine
hydrochloride. The results show that higher amount of pectin in the complexes, with respect to higher
amount of chitosan, produced a more evident porous structure of the nasal inserts, improving water uptake
ability and mucoadhesion capacity. Finally, the presence of increasing amounts of pectin allowed the interaction
with chlorpromazine hydrochloride inducing the formation of less hydratable inserts thus limiting
drug release and permeation. This investigation verifies the formation of polyelectrolyte complexes
between chitosan and pectin at pH values in the vicinity of the pKa interval of the two polymers and confirms
the potential of these complexes, capable of achieving antipsychotic drug delivery in the nasal cavity
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Trust in authorities monitoring the distribution of genetically modified foods: dimensionality, measurement issues, and determinants
No full textBased on a combined internet and mail survey in Germany the independence of indica-tors of trust in public authorities from indicators of attitudes toward genetically modified food is tested. Despite evidence of a link between trust indicators on the one hand and evaluation of benefits and perceived likelihoods of risks, correlation with other factors is found to be moderate on average. But the trust indicators exhibit only a moderate relation with the re-spondents’ preference for either sole public control or a cooperation of public and private bodies in the monitoring of GM food distribution. Instead, age and location in either the New or the Old Lander are found to be significantly related with such preferences
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A critical account of the relationship between institutional trust, risk perception, and technology acceptance with an application to genetically modified foods
No full textThis article critically reflects on the widely held view of a causal chain with trust in public authorities impacting technology acceptance via perceived risk. It first puts forward conceptual reason against this view, as the presence of risk is a precondition for trust playing a role in decision making. Second, results from consumer surveys in Italy and Germany are presented that support the associationist model as counter hypothesis. In that view, trust and risk judgments are driven by and thus simply indicators of higher order attitudes toward a certain technology which determine acceptance instead. The implications of these findings are discussed
PER UNA EDIZIONE CRITICA DELLE RIME DI BARTOLOMEO CAVASSICO
No full textThis PhD thesis consists of:
- An introductory part presenting the figure of the author, a description of the ms. bearing the Rime, an analysis of the form and content of the texts and the social, political and cultural context where they were produced;
- The critical edition of fifty-four poems in italian and fifteen in Bellunese dialect. An introductory cap presents the formal characteristics of the work and provides the context, if necessary; this is followed by the text, reproduced according to generally conservative criteria; at the bottom there is a first band of apparatus, aimed at containing corrections of servile errors; a second band, containing the actual genetic apparatus, bearing any variants or previous redactions of the text; and finally the commentary, aimed at clarifying critical places and pointing out parallels with other authors. For the Bellunese texts, a full translation was also provided.
- A caption index;
- Two lexical indexes, for italian and Bellunese texts, bearing the notable forms;
- Four appendices. Appendix I is a table containing all the poems, classified according to the following criteria: location in the ms., title, genre of the poem, language, possible addressee and brief summary, focusing, in particular, on the (recurring) themes present in the text. Appendix II houses vernacular texts not included in the edition, and Appendix III italian texts that the author has taken from other printings. Appendix IV contains the digital reproduction of six papers from ms. 396 of the Biblioteca Civica of Belluno.Questa tesi di dottorato si compone di:
- Una parte introduttiva che presenta la figura dell'autore, la descrizione del ms. recante le Rime, l'analisi della forma e dei contenuti dei testi e il contesto sociale, politico e culturale in cui sono stati prodotti;
- L'edizione critica commentata di cinquantaquattro poesie in volgare e quindici in dialetto bellunese. Un cappello introduttivo presenta le caratteristiche formali dell'opera e ne fornisce il contesto, qualora necessario; segue il testo, riprodotto secondo criteri generalmente conservativi; in calce si trovano una prima fascia di apparato, volta a contenere le correzioni degli errori servili, una seconda fascia, contenente l'apparato genetico vero e proprio, recante le eventuali varianti o redazioni precedenti del testo, e infine il commento, finalizzato a chiarire i luoghi critici e a segnalare paralleli con altri autori. Per i testi bellunesi si è fornita anche la traduzione integrale in calce.
- Un indice dei capoversi;
- Due indici lessicali, per i testi in volgare e per i testi in bellunese, recanti le forme notevoli;
- Quattro appendici. L'appendice I è una tabella contenente tutti i componimenti, classificati secondo i seguenti criteri: collocazione nel ms., titolo, genere del componimento, lingua, eventuale destinatario e breve riassunto, imperniato, in particolare, sui temi (ricorrenti) presenti nel testo. L'appendice II ospita i testi in volgare non inclusi nell'edizione, mentre l'appendice III i testi in volgare che l'autore ha tratto da altre stampe. L'appendice IV contiene la riproduzione digitale di sei carte del ms. 396 della Biblioteca Civica di Belluno, attraverso la quale si possono osservare la scrittura del notaio e gli interventi sui testi
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Do consumers want public or private bodies to monitor animal friendly production and marketing schemes? And does trust matter?
No full textProducing according to enhanced farm animal welfare (FAW) standards increases costs along the livestock value chain, especially for monitoring certified animal friendly products. In the choice between public or private bodies for carrying out and monitoring certification, consumer preferences and trust play a role. We explore this issue by applying logit analysis involving socio-economic and psychometric variables to survey data from Italy. Results
identify marked consumer preferences for public bodies and trust in stakeholders a key determinant
Etnografia digitale, netnografia e autoetnografia: ricerche tra vecchi punk, giovani neopagani e membri di una vasta comunità BDSM della Repubblica ceca
No full textIl capitolo presenta l'esperienza personale dell'autore, con l'utilizzo dei dati e delle esperienze raccolte attraverso internet, la netnografia come forma di ricerca qualitativa e l'accettazione personale dell'autoetnografia per la comprensione di sé, dell'altro e della cultura. Saranno analizzati 12 studi e ricerche realizzate dallo stesso autore, da solo o in qualità di coautore, tra gli anni 2005 e 2019, su temi di ricerca differenti, ma concentrati su selezionate sottoculture attive nella Repubblica Ceca. Il capitolo è concepito come un'introspezione diacronica in cui l'autore descrive i suoi primi tentativi di utilizzare pagine web e discussioni in internet come fonte di citazioni in articoli scientifici, fino al raggiungimento di una metodologia netnografica più matura.The chapter presents the personal experience of the author, with the use of data and experiences collected through the internet, the netnography as a form of qualitative research, and the personal acceptance of the autoethnography for the understanding of self, other, and culture. It will be analyzed 12 studies and researches realized by the same author, alone or as co-author, between the years 2005 and 2019, on different, but connected research topics concentred on selected sub-cultures active in the Czech Republic. The chapter is conceived as a diachronic introspection where the author describes his first attempts to use web pages and internet discussions as a source of quotations in scientific papers, up to the achievement of a more mature netnographic methodology
Hydroxypropylmethylcellulose films for prolonged delivery of the antipsychotic drug chlorpromazine
No full textObjectives - The aim of this study was to develop transdermal films based on hydroxypropylmethylcellulose with the purpose of improving transdermal permeation of chlorpromazine hydrochloride, an antipsychotic drug used to alleviate the symptoms and signs of psychosis.
Methods - Hydroxypropylmethylcellulose films were prepared and evaluated for their drug content, film thickness, residual water content and bioadhesive properties. In-vitro permeation experiments were performed in the absence and in the presence of permeation enhancers (oleic acid, polysorbate 80, or both) with the purpose of improving drug availability. Other formulative parameters, such as drug and plasticizer concentration and
hydroxypropylmethylcellulose type, were investigated.
Key findings - Either oleic acid and polysorbate 80 had significant effect on drug permeation with respect to the control formulation. In particular films containing a mixture of oleic acid and polysorbate 80 provided the best enhancement activity for chlorpromazine.
Moreover, a decrease in propylene glycol or chlorpromazine content or an increase of hydroxypropylmethylcellulose viscosity provided lower cumulative amounts of drug permeated.
Conclusions - The results obtained confirm that chlorpromazine permeation can be easily modulated by varying the composition of hydroxypropylmethylcellulose-based films. These formulations could serve as candidates for transdermal delivery of antipsychotic drugs
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