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31.
Massimo Dal Monte Maurizio Cammalleri Rosario Amato Salvatore Pezzino Roberta Corsaro Paola Bagnoli Dario Rusciano 《International journal of molecular sciences》2020,21(23)
Melatonin is of great importance for regulating several eye processes, including pressure homeostasis. Melatonin in combination with agomelatine has been recently reported to reduce intraocular pressure (IOP) with higher efficacy than each compound alone. Here, we used the methylcellulose (MCE) rat model of hypertensive glaucoma, an optic neuropathy characterized by the apoptotic death of retinal ganglion cells (RGCs), to evaluate the hypotensive and neuroprotective efficacy of an eye drop nanomicellar formulation containing melatonin/agomelatine. Eye tissue distribution of melatonin/agomelatine in healthy rats was evaluated by HPLC/MS/MS. In the MCE model, we assessed by tonometry the hypotensive efficacy of melatonin/agomelatine. Neuroprotection was revealed by electroretinography; by levels of inflammatory and apoptotic markers; and by RGC density. The effects of melatonin/agomelatine were compared with those of timolol (a beta blocker with prevalent hypotensive activity) or brimonidine (an alpha 2 adrenergic agonist with potential neuroprotective efficacy), two drugs commonly used to treat glaucoma. Both melatonin and agomelatine penetrate the posterior segment of the eye. In the MCE model, IOP elevation was drastically reduced by melatonin/agomelatine with higher efficacy than that of timolol or brimonidine. Concomitantly, gliosis-related inflammation and the Bax-associated apoptosis were partially prevented, thus leading to RGC survival and recovered retinal dysfunction. We suggest that topical melatoninergic compounds might be beneficial for ocular health. 相似文献
32.
Kazuo Tsubota Stephen C. Pflugfelder Zuguo Liu Christophe Baudouin Hyo Myung Kim Elisabeth M. Messmer Friedrich Kruse Lingyi Liang Jimena Tatiana Carreno-Galeano Maurizio Rolando Norihiko Yokoi Shigeru Kinoshita Reza Dana 《International journal of molecular sciences》2020,21(23)
Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint. 相似文献
33.
Maurizio Rossi 《Color research and application》2023,48(1):32-39
In the last decade, the extensive introduction of LED lighting sources has brought elements of innovation to interior lighting design in terms of color. Besides the new tunable white LED source, lighting is no longer exclusively white; indeed, colored lighting has entered the design practice thanks to the positive effects on people's health and mood. Unfortunately, this element of lighting innovation, color, cannot be computed correctly in commercial lighting design software. These computations are based on the assumption that light is only white or defined in terms of RGB triplets in the relative digital color space of computer graphics, which does not have a physically correct relationship with the actual spectral power distribution (SPD) of luminaires. In this paper, attention is focused on a practical design-oriented approach for describing luminaires in lighting design software that also considers the real SPD and the luminous intensity distribution. The focus is on information available to lighting designers who do not have a laboratory to measure light sources and luminaires. This information could be available in online datasheets or as a Cartesian graph from luminaires and light sources manufacturers. Following this approach, a set of functions is proposed that can be easily implemented in lighting design software to improve light sources' color management and allow lighting designers to add SPD data to luminaires. 相似文献
34.
Giancarlo Scalabrin Giovanni Cristofoli Maurizio Grigiante 《Chemical Engineering Communications》2002,189(12):1705-1729
Predictive and semipredictive models for viscosity calculation are currently needed and highly appreciated. Models developed for halogenated refrigerants (HR) and based on Corresponding States (CS) are leading to a prediction accuracy comparable to that of specifically developed models. In the present work, using recently published, highly accurate viscosity dedicated equations, it has been verified that viscosity conforms to a two-parameter CS model is then developed, based on Teja and coworker's three-parameter CS structure. Two fluids of the same family are taken for reference, and the reduced viscosity of a third fluid is obtained in reduced P,T variables. At first the Pitzer acentric factor is proposed as a third parameter, then it is substituted with a temperature-dependent function fitted on saturated viscosity data. The prediction accuracy of the model is comparable to that of the reference fluid equations and, considering its predictive nature, it is a satisfactory tool for the needs of technical applications. 相似文献
35.
Maurizio?ServiliEmail author Roberto?Selvaggini Agnese?Taticchi Sonia?Esposto Gianfrancesco?Montedoro 《Journal of the American Oil Chemists' Society》2003,80(7):685-695
The time of exposure of olive pastes to air contact (TEOPAC) during malaxation was studied as a processing parameter that
could be used to control endogenous oxidoreductases, such as polyphenoloxidase, peroxidase, and lipoxygenase, which affect
virgin olive oil quality. Phenolic and volatile compounds were analyzed in the oils obtained using progressive TEOPAC at three
ripening stages of olives. Multivariate statistical analysis was applied to the raw data. The phenolic concentration of virgin
olive oil progressively decreased with increasing IEOPAC. On the contrary, a positive relationship was found with the concentration
of several volatile compounds responsible for virgin olive oil aroma. The effect of TEOPAC, however, was strictly related
to fruit ripening. 相似文献
36.
Diffusion coefficients D of H 2 , He, O 2 , N 2 , and CO 2 in different rubbery amorphous polymeric matrices were estimated by atomistic molecular dynamics simulations at 298 K using the Einstein relationship, and compared with the relevant experimental values, where available. The simulated diffusion coefficients D of all the gases in all polymers considered almost regularly decreased with increasing molecular gas volumes and increasing polymer glass transition temperature. Further, solubility coefficients and heats of solution were obtained for all gases from Grand Canonical Monte Carlo simulations, which were also used to calculate sorption isotherms. In general, there is a good agreement between experimental and simulated values of diffusion and solubility coefficients for all gases considered. 相似文献
37.
Physical properties of straw lignin-based polymer blends 总被引:1,自引:0,他引:1
Rachele Pucciariello Vincenzo Villani Carlo Bonini Maurizio D'Auria Teresa Vetere 《Polymer》2004,45(12):4159-4169
Lignin powder, obtained from an abundant and low cost source, straw, through a low environmental impact process, the steam explosion, is used for the preparation of blends with low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE) and atactic polystyrene (PS).The obtained blends are processable through the conventional techniques used for thermoplastics; the modulus slightly increases for most lignin-polymer blends, while the tensile stress and elongation reduce. Moreover, lignin acts as a stabilzer against the UV radiation for PS, LDPE and LLDPE. 相似文献
38.
Carlo Bonini Maurizio D'Auria Giacomo Mauriello Rachele Pucciariello Roberto Teghil Daniela Tofani Licia Viggiani Donato Viggiano Francesco Zimbardi 《应用聚合物科学杂志》2001,79(1):72-79
The synthesis of copolymers between lignin from steam‐exploded straw and 1‐ethenylbenzene is described. Beforehand, lignin from steam‐exploded straw was fully characterized by using elemental analysis, ultraviolet spectroscopy, gel permeation chromatography (GPC), Fourier transform infrared (FTIR), and both 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Using a previously described procedure utilizing calcium chloride and hydrogen peroxide as reagents the synthesis of the copolymers was performed. FTIR of the copolymers showed the presence of both lignin and polystyrene. GPC analysis showed the presence of a fraction with high molecular weights. These results were confirmed from both viscosity data and differential calorimetry. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 72–79, 2001 相似文献
39.
Kuwanon‐L as a New Allosteric HIV‐1 Integrase Inhibitor: Molecular Modeling and Biological Evaluation 下载免费PDF全文
Dr. Francesca Esposito Dr. Cristina Tintori Dr. Riccardo Martini Dr. Frauke Christ Prof. Zeger Debyser Roberto Ferrarese Dr. Gianluigi Cabiddu Dr. Angela Corona Dr. Elisa Rita Ceresola Dr. Andrea Calcaterra Dr. Valentina Iovine Prof. Bruno Botta Dr. Massimo Clementi Dr. Filippo Canducci Prof. Maurizio Botta Prof. Enzo Tramontano 《Chembiochem : a European journal of chemical biology》2015,16(17):2507-2512
HIV‐1 integrase (IN) active site inhibitors are the latest class of drugs approved for HIV treatment. The selection of IN strand‐transfer drug‐resistant HIV strains in patients supports the development of new agents that are active as allosteric IN inhibitors. Here, a docking‐based virtual screening has been applied to a small library of natural ligands to identify new allosteric IN inhibitors that target the sucrose binding pocket. From theoretical studies, kuwanon‐L emerged as the most promising binder and was thus selected for biological studies. Biochemical studies showed that kuwanon‐L is able to inhibit the HIV‐1 IN catalytic activity in the absence and in the presence of LEDGF/p75 protein, the IN dimerization, and the IN/LEDGF binding. Kuwanon‐L also inhibited HIV‐1 replication in cell cultures. Overall, docking and biochemical results suggest that kuwanon‐L binds to an allosteric binding pocket and can be considered an attractive lead for the development of new allosteric IN antiviral agents. 相似文献
40.
Small and large scale segmental motion in polymers: estimating cooperativity length by ordinary relaxation experiments 下载免费PDF全文
Marco Pieruccini Andrea Alessandrini Simone Sturniolo Maurizio Corti Attilio Rigamonti 《Polymer International》2015,64(11):1506-1512
We derive a suitable expression for estimating the size of the cooperatively rearranging regions (CRRs) in supercooled polymer melts by fitting data worked out by ordinary relaxation experiments carried out in isothermal conditions. As an example, the average CRR size in poly(n‐butyl methacrylate) in proximity to the glass transition temperature is derived from a stress relaxation experiment performed by means of an atomic force microscopy setup. Good agreement is found with results in the literature derived from measurements of temperature fluctuations (the so‐called Donth method). The temperature dependence of the CRR size is explored for poly(butadiene); in this case the segmental relaxation function is derived through a novel method for the analysis of the efficiency with which free induction decay echoes are refocused in 1H NMR experiments. It is found that the CRR size increases upon cooling. The results derived from the analysis of the NMR data are found to be in satisfactory agreement with those worked out from broadband dielectric spectroscopy data in the literature. © 2015 Society of Chemical Industry 相似文献