67 research outputs found
Artificial molecular-level machines with [Ru(bpy)3]2
A molecular-level machine is an assembly of a discrete number of molecular components (that is, a supramolecular structure) designed to perform mechanical-like movements (output) as a consequence of appropriate external stimuli (input). Like macroscopic machines, molecular-level machines are characterized by (i) the kind of energy input supplied to make them work, (ii) the kind of movement performed by their components, (iii) the way in which their operation can be controlled and monitored, (iv) the possibility to repeat the operation at will and establish a cyclic process, (v) the time scale needed to complete a cycle of operation, and (vi) the function performed. The most convenient way to supply energy to an artificial molecular-level machine is through a photochemical reaction.[Ru(bpy)3]2+(bpy=2,2′-bipyridine) can be used as a photosensitizer to power mechanical movements in machines based on pseudorotaxanes, rotaxanes and catenanes. Besides being used as an external photosensitizer,[Ru(bpy)3]2+can be incorporated in one of the machine components as a "light-fueled" motor. Three types of photochemically driven piston/cylinder systems and a photocontrollable molecular abacus are described. Other kinds of more sophisticated molecular-level machines based on rotaxanes and catenanes are proposed. The extension of the concept of machine to the molecular level is important not only for the sake of basic research, but also for the growth of nanoscience and the development of nanotechnology
Photochemical investigation of a photochromic diarylethene compound that can be used as a wide range actinometer
The photochromic diarylethene derivative 1,2-bis(5-(4-ethynylphenyl)-2-methylthiophen-3-yl)perfluorocyclopentene (1) was submitted to photochemical, thermal stability and fatigue resistance studies in acetonitrile, also to evaluate its possible application as a new actinometer. This photochromic system covers a wide spectral absorption range, with intense bands in the UV and visible regions for the open-ring and closed-ring isomers, respectively. Very high ring-closure quantum yield values were obtained, in contrast with the low ring-opening quantum yields, which are nevertheless high enough to exploit 1 as an actinometer. The procedure required to determine the photon flux of an irradiation source with this fatigue resistant compound is indeed very simple
Photoinduced electron flow in a self-assembling supramolecular extension cable
We report the design, bottom-up construction, characterization, and operation of a supramolecular system capable of mimicking the function played by a macroscopic electrical extension cable. The system is made up of a light-powered electron source, an electron drain, and a cable as the molecular components programmed to self-assemble by means of two distinct plug/socket junctions. Such connections are reversible and can be operated independently by orthogonal chemical inputs. In the source-connector-drain supermolecule, photoinduced electron transfer from source to drain occurs, and it can be switched off by dual-mode chemically controlled disassembling of the molecular components.Ferrer Ribera, RB.; Rogez, G.; Credi, A.; Ballardini, R.; Gandolfi, MT.; Balzani, V.; Liu, Y.... (2006). Photoinduced electron flow in a self-assembling supramolecular extension cable. Proceedings of the National Academy of Sciences. 103(49):18411-18416. doi:10.1073/pnas.060645910318411184161034
A decalogue for end-of-life care in Internal Medicine
Since a large number of patients with chronical medical diseases die in hospital, often in an internal medicine ward, internists are urged to improve their expertise in end-of-life (EOL) care, which is a neglected part of their academic education. Recently, FADOI (the Italian Federation of the Associations Hospital Doctors on Internal Medicine) has addressed EOL-medicine in many ways, promoting many scientific meetings on this and allied topics, providing educational material made available in its website on a free basis and establishing an ad hoc Committee charged with the task of organizing dedicated events annually. The Committee has also elaborated a series of recommendations on EOL-care in internal medicine (a decalogue), reflecting largely shared visions. It has been endorsed also by ANIMO (the Association of the Italian Nurses working in an Internal Medicine Department). The decalogue for EOL care in internal medicine is issued here, and calls for its diffusion and implementation. The driving concept is that doctors and nurses must feel responsible for disregarding appropriate EOL-care for the dying patients, because delaying it means to add suffering and discomfort to them in the final phase of their existence
Mosquito-Borne Diseases and ‘One Health’: The Northwestern Italian Experience
In Italy, the surveillance of Mosquito-Borne Diseases (MBDs) is regulated by two national preparedness plans: (1) for West Nile and Usutu viruses, integrating human and veterinary surveillance in order to early detect viruses circulation and to quickly apply control measures aimed at reducing the risk of transmission through blood and blood components and (2) for Arbovirosis transmitted by Aedes mosquitoes, mainly Chikungunya, Dengue and Zika viruses, based on surveillance of both imported and autochthonous human cases. This chapter reports the results of the application of these National Plans in Northwestern Italy and their impact for human health. In detail, we present the coordinated activities enforced in Piemonte and Liguria Regions, as a good example of the ‘One Health approach’ to control MBDs and prevent human transmission
Pilot Study of the Mechanism of Action of Preoperative Trastuzumab in Patients with Primary Operable Breast Tumors Overexpressing HER2
Abstract
Purpose: To elucidate the mechanism by which trastuzumab, a humanized monoclonal antibody against HER2 with proven survival benefit in women with HER2-positive metastatic breast cancer, mediates its antitumor activity.
Experimental Design: A pilot study including 11 patients with HER2-positive tumors treated in a neo-adjuvant setting with trastuzumab was performed. Trastuzumab was administered i.v. at a dose of 4 mg/kg followed by three weekly i.v. doses of 2 mg/kg. The primary tumor was surgically removed 7 days after the last treatment. Surgical samples, tumor biopsies, and lymphocytes from these patients were collected for biological studies.
Result: Clinical data indicated one complete pathological remission and four partial remissions using RECIST (Response Evaluation Criteria in Solid Tumors). Trastuzumab was well tolerated and neither serious adverse events nor changes in cardiac function were observed during this short-term treatment and after surgery. The biological data showed that, independent of response, (a) all patients showed high levels of circulating trastuzumab; (b) saturating level of trastuzumab was present in all of the tumors; (c) no down-modulation of HER2 was observed in any tumors; (d) no changes in vessel diameter was observed in any tumors; (e) no changes in proliferation was observed in any tumors; and (f) a strong infiltration by lymphoid cells was observed in all cases. Patients with complete remission or partial remission were found to have a higher in situ infiltration of leukocytes and a higher capability to mediate in vitro antibody-dependent cellular cytotoxicity activity.
Conclusions: The results of this pilot study argue against trastuzumab activity in patients through down-modulation of HER2 but in favor of antibody-dependent cellular cytotoxicity guiding efforts to optimize the use of trastuzumab in breast cancer patients
Activity of chemotherapy in mucinous ovarian cancer with a recurrence free interval of more than 6 months: results from the SOCRATES retrospective study
<p>Abstract</p> <p>Background</p> <p>Mucinous ovarian carcinoma have a poorer prognosis compared with other histological subtypes. The aim of this study was to evaluate, retrospectively, the activity of chemotherapy in patients with platinum sensitive recurrent mucinous ovarian cancer.</p> <p>Methods</p> <p>The SOCRATES study retrospectively assessed the pattern of care of a cohort of patients with recurrent platinum-sensitive ovarian cancer observed in the years 2000–2002 in 37 Italian centres. Data were collected between April and September 2005. Patients with recurrent ovarian cancer with > 6 months of platinum free interval were considered eligible.</p> <p>Results</p> <p>Twenty patients with mucinous histotype and 388 patients with other histotypes were analyzed. At baseline, mucinous tumours differed from the others for an higher number of patients with lower tumor grading (p = 0.0056) and less advanced FIGO stage (p = 0.025). At time of recurrence, a statistically significant difference was found in performance status (worse in mucinous, p = 0.024). About 20% of patients underwent secondary cytoreduction in both groups, but a lower number of patients were optimally debulked in the mucinous group (p = 0.03). Patients with mucinous cancer received more frequently single agent platinum than platinum based-combination therapy or other non-platinum schedules as second line therapy (p = 0.026), with a response rate lower than in non-mucinous group (36.4% vs 62.6%, respectively, p = 0.04). Median time to progression and overall survival were worse for mucinous ovarian cancer. Finally, mucinous cancer received a lower number of chemotherapy lines (p = 0.0023).</p> <p>Conclusion</p> <p>This analysis shows that platinum sensitive mucinous ovarian cancer has a poor response to chemotherapy. Studies dedicated to this histological subgroup are needed.</p
Understanding Factors Associated With Psychomotor Subtypes of Delirium in Older Inpatients With Dementia
Onset of gynecomastia in a male patient under sunitinib treatment for metastatic clear-cell renal carcinoma
none4The first report of an association between administration of sunitinib (oral multitargeted tyrosine-kinase inhibitor recently authorized for treatment of metastatic clear-cell renal carcinoma) and onset of male gynecomastia.noneBallardini P; Margutti G; Aliberti C; Manfredini RBallardini, P; Margutti, G; Aliberti, C; Manfredini, Robert
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