37 research outputs found
‘Hauendo lui publicato sette fogli di carta’ : Leandro Pizzoni e la reputazione scientifica di Galileo
No full textLeandro Pizzoni and Galileo’s scientific reputation. The Letter to Costanzo Salvi published in 1625 by Leandro Pizzoni has been totally neglected in Galileo’s scholarship because of serious misunderstandings concerning its authorship, nature and scope. This article calls attention to this text and shows that – however inept and heavily reliant on previous sources, such as Orazio Grassi and Francesco Sizzi – Pizzoni’s criticism of Salvi is historically interesting because it provides evidence of the reaction of a conservative Aristotelian against several aspects of Galileo’s teachings. Not content with criticizing Salvi’s Atomism, Pizzoni openly attacks Galileo’s scientific reputation, qualifies his way of philosophizing as «extraordinary», and refutes his astronomical discoveries, recalling that they had been badly received at the University of Padua. Moreover, Pizzoni praises Aristotle in terms that are strikingly similar to the ones employed by Galileo when penning a satirical portrait of dogmatic Aristotelians in his Dialogue on the two Chief World Systems
Dal 2D al 3D nella diagnosi e pianificazione terapeutica dei canini mascellari inclusi = From 2D to 3D in the diagnosis and treatment planning of maxillary impacted canines
No full textObjectives The aim of this article is to present the progress in diagnosis and treatment planning of maxillary impacted canines, thanks to the introduction of three-dimensional X-ray techniques into clinical practice, such as the different types of computed tomography, and of the modern softwares which permit the digital reprocessing of DICOM data.
Materials and methods The main features of the 3D evaluation techniques are described with examples of spatial localization of impacted elements, presenting the different functions available with the modern softwares that allow 3D reconstruction.
Results The impaction of permanent upper canines is an eruption anomaly, whose prevalence is 1–3%. It is a complex problem that may lead to severe complications, and requires an accurate diagnosis associated to an individual treatment plan, both now possible thanks to modern three-dimensional reconstruction and virtual simulation.
Conclusion The many opportunities in diagnosis and treatment planning, now available thanks to the radiologic and software development, and are constantly evolving. Therefore a continuous update is necessary for the clinician to be able to offer the patients the best possible treatment
Ultrasonic versus conventional bracket removal and enamel clean-up : a preliminary study
No full text
[Congenital neutrophil defects and periodontal diseases]
No full textAn alteration of the immune system function is one of the main factors involved in the development of periodontal disease. Polymorpho-nuclear neutrophil leukocytes (PMN) play a crucial role in the cell-mediated immune response against bacterial challenge. The mechanism of neutralization of pathogen microorganisms by PMNs involves many different steps: adhesion to capillary endothelium in the inflamed region, trans-endothelial migration, chemotaxis, phagocytosis and, ultimately, bacterial killing by oxidative and non-oxidative mechanisms. A defect in one of these steps leads to altered neutrophil function and, consequently, to a higher host susceptibility to periodontal tissue infection. The main intrinsic neutrophil diseases such as neutropenia, leukocyte adhesion deficiency (LAD-1), Chediak-Higashi syndrome, Papillon-Lefèvre syndrome, chronic granulomatous disease (CGD), are often related to severe and early-onset forms of periodontitis, as described by many evidences in the literature. Therefore PMN dysfunctions, both intrinsic and extrinsic, represent an important risk factor for periodontal disease. Studies on the basic molecular mechanisms of such dysfunctions, also in terms of genetic polymorphisms, recently allowed to identify some specific markers related to a higher susceptibility to the development of disease. Many researches have yet to be performed aiming to gain insight on the dynamics of PMN activation and interaction with other cells, in order to improve and modulate neutrophil function and to develop specific approaches for care and prevention of periodontal diseases
[Neutrophil physiology: role and mechanism of action in the immune response at gingival level]
No full textPolymorphonuclear neutrophil granulocytes (PMN) are considered the most important cells of the host immune response against bacterial challenge. The functional mechanism of PMN consists of different steps: tethering, rolling, primary adhesion to the vascular wall, firm adhesion to the activated endothelium in the inflamed region, trans-migration across endothelium, chemotaxis, contact with the bacterium and phagocytosis and, finally, killing of the micro-organism by releasing hydrolytic enzymes and/or by production of toxic substances such as free radicals. Each of these steps is controlled by interactions between cells and many components of the immune system or inflammatory mediators. These interactions generate specific signals, important for cell regulation. Recent technological advances in molecular biology and immunobiology allowed to disclose the precise role of various molecules involved in the immune response, that regulate PMN function; conversely, more factors have been identified, whose role is still unknown. In the process of adhesion, for example, many classes of molecules are involved (selectins, integrins, ICAMs). The interaction of these molecules (es.: selectin) with their ligands (non completely discovered) is characteristic of specific stages, but may also regulate the successive steps (integrin activation). In periodontal infections, PMNs of gingival tissue migrate towards bacteria of dental plaque along a chemotactic gradient of specific factors (ICAM-1, IL-8) produced by cells of the junctional epithelium. Such gradient is essential to drive PMNs through molecular traffic. Among the mechanisms used by PMNs to kill bacteria, the importance of nitric oxide (NO) production has been recently pointed out
Enhanced therapeutic effect of APAVAC immunotherapy in combination with dose-intense chemotherapy in dogs with advanced indolent B-cell lymphoma
No full textThe aim of this non-randomized controlled trial was to compare time to progression (TTP), lymphoma-specific survival (LSS), and safety of an autologous vaccine (consisting of hydroxyapatite ceramic powder and Heat Shock Proteins purified from the dogs' tumors, HSPPCs-HA) plus chemotherapy versus chemotherapy alone in dogs with newly diagnosed, clinically advanced, histologically confirmed, multicentric indolent B-cell lymphoma. The vaccine was prepared from dogs' resected lymph nodes and administered as an intradermal injection. Forty-five client-owned dogs were enrolled: 20 dogs were treated with dose-intense chemotherapy, and 25 received concurrent immunotherapy. Both treatment arms were well tolerated, with no exacerbated toxicity in dogs also receiving the vaccine. TTP was significantly longer for dogs treated with chemo-immunotherapy versus those receiving chemotherapy only (median, 209 versus 85 days, respectively, P= 0.015). LSS was not significantly different between groups: dogs treated with chemo-immunotherapy had a median survival of 349 days, and those treated with chemotherapy only had a median survival of 200 days (P= 0.173). Among vaccinated dogs, those mounting an immune response had a significantly longer TTP and LSS than those with no detectable response (P= 0.012 and P= 0.003, respectively). Collectively these results demonstrate that vaccination with HSPPCs-HA may produce clinical benefits with no increased toxicity, thereby providing a strategy for enhancing chemotherapy in dogs with advanced indolent lymphoma
