528 research outputs found

    Langmuir-Schäfer Films of an Amphiphilic Ruthenium Complex Bearing an “Almost-Naked” Multi-Charged Head-Group

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    In this paper the preparation and characterization of Langmuir-Scha¨fer (LS) films of a novel amphiphilic dipolar complex, [RuII(NH3)5(N-dodecyl-4,4¢-bpy)](PF6)3 (1), are reported. Preparation of these films, otherwise precluded utilizing standard Langmuir procedures, is achieved by using a subphase at relatively high ionic strength, by addition of NH4PF6. The morphology and the spectroscopic features of the floating films are investigated by Brewster angle microscopy and UV-vis reflection spectroscopy at the water-air interface, respectively, whereas LS films are characterized by absorption spectroscopy and atomic force microscopy. The overall results indicate the existence of aggregates of 1 and formation of homogeneous, densely packed layers. The presented approach could represent a general method to achieve Langmuir-Blodgett films of amphiphilic metal complexes having an “almost naked” multicharged headgroup

    Molecular mechanisms of photosensitization induced by drugs XIV: Two different behaviours in the photochemistry and photosensitization of antibacterials containing a fluoroquinolone like chromophore

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    This paper deals with the photosensitizing activity of FLQs towards two different biosubstrates, membrane and DNA. Thein vitrophototoxic activity of these drugsvs.DNA presents peculiar features with respect to thatvs.membranes, probably due to a specific binding of the drugs to the double helix and to the operativeness of different photosensitization mechanisms with the two types of biosubstrates. A description of the UVA photochemistry and the photosensitizing properties of two significant examples in the FLQ family is reported. The investigated compounds are Enoxacin, 1-ethyl-6-fluoro-1,4-dihydro-4- oxo-7-[1-piperazinyl]-1,8-naphtyridine-3-carboxilic acid and Rufloxacin, 9-fluoro-2,3-dihydro-10-4´-methyl- 1´-piperazinyl-7-oxo-7H-pyrido[1,2,3−de]-1,4-benzothiazine-6-carboxylic acid

    Photoresponsive multilayer films by assembling cationic amphiphilic cyclodextrins and anionic porphyrins at the air/water interface

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    Densely packed hybrid monolayers of amphiphilic cyclodextrins incorporating hydrophilic porphyrins are formed at the air/water interface through electrostatic interaction and can be transferred onto quartz substrates by Langmuir–Scha¨fer deposition. The resulting multilayers exhibit a good response to light excitation as proven by fluorescence emission, triplet– triplet absorption and singlet oxygen photogeneration

    Comparison between two different modes of non-invasive ventilatory support in preterm newborn infants with respiratory distress syndrome mild to moderate: preliminary data

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    Despite of improved survival of premature infants, the incidence of long term pulmonary complications, mostly associated with ventilation-induced lung injury, remains high. Non invasive ventilation (NIV) is able to reduce the adverse effects of mechanical ventilation. Although nasal continuous positive airway pressure (NCPAP) is an effective mode of NIV, traumatic nasal complications and intolerance of the nasal interface are common. Recently high flow nasal cannula (HFNC) is emerging as a better tolerated form of NIV, allowing better access to the baby's face, which may improve nursing, feeding and bonding. HFNC may be effective in the treatment of some neonatal respiratory conditions while being more user-friendly for care-givers than conventional NCPAP. Limited evidence is available to support the specific role, efficacy and safety of HFNC in newborns and to demonstrate efficacy compared with NCPAP; some studies suggest a potential role for HFNC in respiratory care of the neonate as a distinct non invasive ventilatory support. We present the preliminary data of a randomized clinical trial; the aim of this study was to assess efficacy and safety of HFNC compared to NCPAP in preterm newborns with mild to moderate respiratory distress syndrome (RDS)

    “Three-bullets” loaded mesoporous silica nanoparticles for combined photo/chemotherapy

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    This contribution reports the design, preparation, photophysical and photochemical characterization, as well as a preliminary biological evaluation of mesoporous silica nanoparticles (MSNs) covalently integrating a nitric oxide (NO) photodonor (NOPD) and a singlet oxygen (1O2) photosensitizer (PS) and encapsulating the anticancer doxorubicin (DOX) in a noncovalent fashion. These MSNs bind the NOPD mainly in their inner part and the PS in their outer part in order to judiciously exploit the different diffusion radius of the cytotoxic NO and 1O2. Furthermore this silica nanoconstruct has been devised in such a way to permit the selective excitation of the NOPD and the PS with light sources of different energy in the visible window. We demonstrate that the individual photochemical performances of the photoactive components of the MSNs are not mutually affected, and remain unaltered even in the presence of DOX. As a result, the complete nanoconstruct is able to deliver NO and 1O2 under blue and green light, respectively, and to release DOX under physiological conditions. Preliminary biological results performed using A375 cancer cells show a good tolerability of the functionalized MSNs in the dark and a potentiated activity of DOX upon irradiation, due to the effect of the NO photoreleased

    Monoclonal antibodies for the treatment of non-haematological tumours: Update of an expanding scenario

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    Introduction: The identification of cell membrane-bound molecules with a relevant role in cancer cell survival prompted the development of moAbs to block the related pathways. In the last few years, the number of approved moAbs for cancer treatment has constantly increased. Many of these drugs significantly improved the survival outcomes in patients with solid tumours.Areas covered: In this review, all the FDA-approved moAbs in solid tumours have been described. This is an update of moAbs available for cancer treatment nowadays in comparison with the moAbs approved until few years ago. The moAbs under development are also discussed here.Expert opinion: The research on cancer antigens as therapeutic targets led to an expanding scenario of available treatment options in non-haematological malignancies. In a few years, the number of approved drugs has increased rapidly. Some of these agents are actually on label in combination with standard chemotherapy. Only some of them can be delivered as monotherapy. The research on these new drugs is addressing both the identification of further target molecules in key cancer-related pathways and the improvement of drug effectiveness by changing the affinity and the selectivity of a moAb relative to its target
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