273 research outputs found
Walsh Gallery and Alberto Italian Studies Institute present “Currency, Culture and the Ron D’Argenio Collection of Coins and Antiquities”
The Effects of Skin to Skin Contact on Newborns With Neonatal Abstinence Syndrome
A literature search was conducted on the effects of skin to skin contact on newborns with neonatal abstinence syndrome (NAS). In the United States, research has shown that typically the first intervention for NAS newborns is immediate pharmacological treatment, but new research poses that non-pharmacological interventions such as skin to skin contact, or kangaroo care, benefit the newborn greatly without exposing them to additional opiates or other addictive substances. The literature search implemented on CINAHL and Nursing Reference Center Plus was performed using the following search terms: neonat*, skin to skin*, babywear*, kangaroo car*, neonatal abstinence syndrome*, NAS*, and in utero substance expos*. Articles that did not directly discuss the use of skin to skin contact on newborns with NAS and skin to skin contact not related to newborns with NAS were excluded. The limitations of this review were the many variations of how skin to skin contact is implemented and when. A total of 10 articles met inclusion criteria. The literature indicates that skin to skin contact directly benefits newborns by decreasing their withdrawal symptoms when used as an intervention. Based on these findings there is strong support for the integration of skin to skin contact on newborns with neonatal abstinence syndrome as the priority non-pharmacological intervention in practice post-partum. Evidence indicates that the skin to skin intervention should be universally implemented in the NAS newborn plan of care
SL3D: un sistema per la realizzazione di presentazioni tridimensionali
L'applicazione fornisce un ambiente tridimensionale per la creazione e la visualizzazione di diapositive, consentendo all'utente di creare interattivamente una presentazione con modalitĂ simili a quelle dei comuni strumenti per presentazioni (PowerPoint, Impress, Keynote) con l'interazione classica dei software 3D
Validation of computational liquefaction for tailings: Tar Island slump
Finite-element analyses using critical state theory proved necessary to understand the development of static liquefaction during three recent large tailing dam failures at Fundao (in Brazil), Cadia (in Australia) and Brumadinho (in Brazil). However, the complexity of these events prevents these analyses being viewed as a complete validation of the methodology. Here the authors evaluate a far simpler case of static liquefaction: The 1974 Tar Island slump (in Canada). This upstream slump involved a rapid drop of 5 m during construction of a 12.5 m high upstream raise over loose tailings. While not a dam stability issue, the event has the attraction for validation of being load-induced, with simple geometry, and with known material properties and in situ state. The computed liquefaction develops from a prior drained condition before propagating rapidly undrained-there are similarities to the video record at Brumadinho (an animation is provided as online supplementary material to illustrate this). A range of scenarios are explored, with the base case of taking reported conditions at face value giving deformations close to those measured. An important aspect was using elastic shear moduli determined by geophysical methods. The analyses were carried out with commercial software (Plaxis) and used critical state theory with largely familiar soil properties measured by standard methods
PHOTOACTIVABLE LACTOSYLCERAMIDE DERIVATIVES: PREPARATION AND USE IN THE COMPREHENSION OF THE GENERATION OF OXIDATIVE SPECIES IN NEUTROPHILS.
Photoactivable lactosylceramide derivatives: preparation and use in the comprehension of the generation of oxidative species in neutrophils.
Glycosphingolipids (GSL) are anphiphilic membrane components consisting in a hydrophobic moiety, ceramide, and a hydrophilic oligosaccharide headgroup. Ceramide is responsible for their insertion into the outer layer of plasma membranes, with the oligosaccharide chain protruding in the extracellular environment. GSLs participate to the signaling processes across the membrane1 determining the lateral organization of cellular membranes and modulating the function of several classes of membrane proteins.2 Their function rely to the ability they have to form clusters with sphingomyelin, ceramide, cholesterol and signal trasduction proteins such as GPI-anchored and acylated proteins (including Src family-kinases), to form specialized membrane domains called \u201clipid-rafts\u201d.3
In mature neutrophils, which play the first line of defense against invading microorganisms and have an important role in acute inflammatory reaction, more than 70% of GSLs are LacCers, which are aberrantly expressed at high levels on mature neutrophils. It is possible that LacCer activates NADPH oxidase, thereby affecting the functions of superoxide-producing cells. However, the mechanisms by which LacCer activates NADPH oxidase in neutrophils have not yet been well characterized.
It is known that lactosylceramide (LacCer) is specifically coupled with Src family kinase Lyn in plasma membrane microdomains of human neutrophils. Ligand binding to LacCer activates Lyn, resulting in neutrophils functions, such as superoxide generation and migration.4 The \u3b2-D-Gal-(1\u21924)-\u3b2-D-Glc structure is necessary but it is not sufficient for LacCer-mediated Lyn activation. For this function, the presence of a LacCer molecular species with a ceramide containing a very long fatty acid is also required.
GSLs containing very long fatty acids might participate in reducing the membrane thickness through interdigitation of the two membrane leaflets. The interdigitation is proposed to be the switch for the transduction of information throughout the membrane perhaps by allowing contact and interaction between proteins belonging to the two layers of the plasma membrane.5 Anyway the molecular mechanism by which the interactions between GSLs and protein influence the cell functions has still to be elucidated.
The aim of this thesis is to give a contribute in the comprehension of the intermediate steps of the signaling process mediated by Lyn proteins. In particular, the purpose is to explore the role of long chain LacCer in this process, with a particular interest in the identification of the proteins associated with LacCer in the immune response to several microorganisms in human neutrophils.
The cross-linkage between gangliosides and proteins can be investigated by cell photolabeling using radioactive photoactivable gangliosides carrying the reactive group at different positions of the molecule. In fact the photoactivable group, when illuminated, yield a very reactive intermediate that covalently binds to the molecules in the environment.6,7
With the final aim to identify LacCer associated proteins, we have developed probes 1 and 2, containing one or two photoactivable groups, located at specific points of the molecule and, in principle, capable to interact with proteins belonging to the cytoplasmic and/or to the extracellular membrane layer.
Probes 1 e 2 display an acyl chain long enough for LacCer-mediated Lyn activation, as preliminary experiments have shown.8 The initial task of the thesis has been the preparation of the acyl derivatives, suitable for the construction of probes 1 and 2. The synthetic efforts were mainly devoted to prepare the proper aminoacid derivatives for conjugation to lactosylsphingosine and subsequent derivatization with the photoactivable probe. Both the C-18 \u3c9-aminoacid and the C-18 \u3b1,\u3c9-diaminoacid were prepared by chemical synthesis, since they are not commercially available. In addition, the synthesis of the long chain \u3b1,\u3c9-diamino acid can be very interesting for the possibility of simultaneous capture of the proteins belonging to the two leaflets.
The C-18 \u3c9-aminoacid was derived from commercially available octadecandioic acid through a eight steps synthetic pathway. On the contrary, the \u3b1,\u3c9-diamino homologue was constructed in seven steps by subsequent condensations of shorter building blocks, starting from suitable protected aspartic acid, through a synthetic route that showed several tricky points.
Both aminoacids, activated as pentafluorophenolates, have been coupled to lactosylsphingosine, which has been previously tritiated in order to follow the sphingolipid biological pathway. The obtained proper LacCers were finally derivatized with nitrophenilazide to give the target probes 1 and 2.
To assess the capability of an \u3b1,\u3c9-diamino fatty acid functionalized probe, i.e. 2, to be internalized by the cells, we have designed probe 3 in which the hydrophilic moiety is ganglioside GM1.
Previous studies have in fact demonstrated the capability of GM1, with one photoactivable group at the end of the fatty chain, to be inserted in the membrane lipid core in a way that closely resembles that of endogenous gangliosides.9
Photolabelling experiments are now in progress both in Milan (probe 3, GM1) and in Japan (probe 1 and 2, experiments on human neutrophils in collaboration with Professor Iwabuchi)
Increased bile duct complications and/or chronic rejection in crossmatch positive human liver allografts
La bellezza come strumento di accesso alla conoscenza storica. La mostra Scuole come capanne. Libri come opere d’arte. Dal Brasile all’Agro romano
The essay deals with the exhibition “Schools as huts and books as works of art. From Brazil to the Agro Romano” (Scuole come capanne e libri come opere d’arte. Dal Brasile all’Agro Romano), which collected educational materials and objects of daily life made for the schools of the Brazilian Indians, as well as those of the farmers of the Agro Romano of the early 20th Century. The dialogue between these materials underlines the centrality of beauty in education and in creating a better world
Impact of Normothermic Preservation with Extracellular Type Solution Containing Trehalose on Rat Kidney Grafting from a Cardiac Death Donor
BACKGROUND: The aim of this study was to investigate factors that may improve the condition of a marginal kidney preserved with a normothermic solution following cardiac death (CD) in a model of rat kidney transplantation (RTx). METHODS: Post-euthanasia, Lewis (LEW) donor rats were left for 1 h in a 23°C room. These critical kidney grafts were preserved in University of Wisconsin (UW), lactate Ringer's (LR), or extracellular-trehalose-Kyoto (ETK) solution, followed by intracellular-trehalose-Kyoto (ITK) solution at 4, 23, or 37°C for another 1 h, and finally transplanted into bilaterally nephrectomized LEW recipient rats (n = 4-6). Grafts of rats surviving to day 14 after RTx were evaluated by histopathological examination. The energy activity of these marginal rat kidneys was measured by high-performance liquid chromatography (HPLC; n = 4 per group) and fluorescence intensity assay (n = 6 per group) after preservation with UW or ETK solutions at each temperature. Finally, the transplanted kidney was assessed by an in vivo luciferase imaging system (n = 2). RESULTS: Using the 1-h normothermic preservation of post-CD kidneys, five out of six recipients in the ETK group survived until 14 days, in contrast to zero out of six in the UW group (p<0.01). Preservation with ITK rather than ETK at 23°C tended to have an inferior effect on recipient survival (p = 0.12). Energy activities of the fresh donor kidneys decreased in a temperature-dependent manner, while those of post-CD kidneys remained at the lower level. ETK was superior to UW in protecting against edema of the post-CD kidneys at the higher temperature. Luminescence intensity of successful grafts recovered within 1 h, while the intensity of grafts of deceased recipients did not change at 1 h post-reperfusion. CONCLUSIONS: Normothermic storage with extracellular-type solution containing trehalose might prevent reperfusion injury due to temperature-dependent tissue edema
- …