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961.
In situ evaluation of surface roughness and micromorphology of temporary soft denture liner materials at different time intervals
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Objective
To perform an in situ evaluation of surface roughness and micromorphology of two soft liner materials for dentures at different time intervals.Background
The surface roughness of materials may influence the adhesion of micro‐organisms and inflammation of the mucosal tissues. The in situ evaluation of surface roughness and the micromorphology of soft liner materials over the course of time may present results different from those of in vitro studies, considering the constant presence of saliva and food, the changes in temperature and the pH level in the oral cavity.Materials and methods
Forty‐eight rectangular specimens of each of the two soft liner materials were fabricated: a silicone‐based material (Mucopren Soft) and an acrylic resin‐based material (Trusoft). The specimens were placed in the dentures of 12 participants (n = 12), and the materials were evaluated for surface roughness and micromorphology at different time intervals: 0, 7, 30 and 60 days. Roughness (Ra) was evaluated by means of a roughness tester. Surface micromorphology was evaluated by scanning electron microscopy.Results
Analysis of variance for randomised block design and Tukey's test showed that surface roughness values were lower in the groups using the silicone‐based material at all the time intervals (P < .0001). The average surface roughness was higher at time interval 0 than at the other intervals, for both materials (P < .0001). The surface micromorphology showed that the silicone material presented a more regular and smoother surface than the acrylic resin‐based material.Conclusion
The surface roughness of acrylic resin‐based and silicone‐based denture soft liner materials decreased after 7 days of evaluation, leading to a smoother surface over time. The silicone‐based material showed lower roughness values and a smoother surface than the acrylic resin‐based material, thereby making it preferred when selecting more appropriate material, due its tendency to promote less biofilm build‐up. 相似文献962.
Joost Willebrords Michaël Maes Isabel Veloso Alves Pereira Tereza Cristina da Silva Veronica Mollica Govoni Valéria Veras Lopes Sara Crespo Yanguas Valery I. Shestopalov Marina Sayuri Nogueira Inar Alves de Castro Anwar Farhood Inge Mannaerts Leo van Grunsven Jephte Akakpo Margitta Lebofsky Hartmut Jaeschke Bruno Cogliati Mathieu Vinken 《生物化学与生物物理学报:疾病的分子基础》2018,1864(3):819-830
963.
Maria Grazia Murrali Marco Schiavina Valerio Sainati Wolfgang Bermel Roberta Pierattelli Isabella C. Felli 《Journal of biomolecular NMR》2018,70(3):167-175
The increasingly recognized biological relevance of intrinsically disordered proteins requires a continuous expansion of the tools for their characterization via NMR spectroscopy, the only technique so far able to provide atomic-resolution information on these highly mobile macromolecules. Here we present the implementation of projection spectroscopy in 13C-direct detected NMR experiments to achieve the sequence specific assignment of IDPs. The approach was used to obtain the complete backbone assignment at high temperature of α-synuclein, a paradigmatic intrinsically disordered protein. 相似文献
964.
Veronica Costiniti Iolanda Spera Roberta Menabò Erika M. Palmieri Alessio Menga Pasquale Scarcia Vito Porcelli Rosanna Gissi Alessandra Castegna Marcella Canton 《生物化学与生物物理学报:疾病的分子基础》2018,1864(9):3050-3059
Monoamine oxidase (MAO), a mitochondrial enzyme that oxidizes biogenic amines generating hydrogen peroxide, is a major source of oxidative stress in cardiac injury. However, the molecular mechanisms underlying its overactivation in pathological conditions are still poorly characterized.Here, we investigated whether the enhanced MAO-dependent hydrogen peroxide production can be due to increased substrate availability using a metabolomic profiling method. We identified N1-methylhistamine -the main catabolite of histamine- as an important substrate fueling MAO in Langendorff mouse hearts, directly perfused with a buffer containing hydrogen peroxide or subjected to ischemia/reperfusion protocol. Indeed, when these hearts were pretreated with the MAO inhibitor pargyline we observed N1-methylhistamine accumulation along with reduced oxidative stress. Next, we showed that synaptic terminals are the major source of N1-methylhistamine. Indeed, in vivo sympathectomy caused a decrease of N1-methylhistamine levels, which was associated with a marked protection in post-ischemic reperfused hearts. As far as the mechanism is concerned, we demonstrate that exogenous histamine is transported into isolated cardiomyocytes and triggers a rise in the levels of reactive oxygen species (ROS). Once again, pargyline pretreatment induced intracellular accumulation of N1-methylhistamine along with decrease in ROS levels. These findings uncover a receptor-independent mechanism for histamine in cardiomyocytes.In summary, our study reveals a novel and important pathophysiological causative link between MAO activation and histamine availability during pathophysiological conditions such as oxidative stress/cardiac injury. 相似文献
965.
966.
Roberta Loddo Valeria Francesconi Erik Laurini Silvia Boccardo Suzana Aulic Maurizio Fermeglia Sabrina Pricl Michele Tonelli 《Bioorganic & medicinal chemistry》2018,26(4):855-868
Bovine viral diarrhea virus (BVDV) infection is still a plague that causes important livestock pandemics. Despite the availability of vaccines against BVDV, and the implementation of massive eradication or control programs, this virus still constitutes a serious agronomic burden. Therefore, the alternative approach to combat Pestivirus infections, based on the development of antiviral agents that specifically inhibit the replication of these viruses, is of preeminent actuality and importance.Capitalizing from a long-standing experience in antiviral drug design and development, in this work we present and characterize a series of small molecules based on the 9-aminoacridine scaffold that exhibit potent anti-BVDV activity coupled with low cytotoxicity. The relevant viral protein target – the RNA-dependent RNA polymerase – the binding mode, and the mechanism of action of these new antivirals have been determined by a combination of in vitro (i.e., enzymatic inhibition, isothermal titration calorimetry and site-directed mutagenesis assays) and computational experiments. The overall results obtained confirm that these acridine-based derivatives are promising compounds in the treatment of BVDV infections and, based on the reported structure-activity relationship, can be selected as a starting point for the design of a new generation of improved, safe and selective anti-BVDV agents. 相似文献
967.
968.
Eleonora Mauri Robertino Dilena Antonio Boccazzi Dario Ronchi Daniela Piga Fabio Triulzi Delia Gagliardi Roberta Brusa Irene Faravelli Nereo Bresolin Francesca Magri Stefania Corti Giacomo P. Comi 《BMC neurology》2018,18(1):220
Background
Leber’s hereditary optic neuropathy (LHON) is a mitochondrial disease characterized by visual loss consequent to optic nerve atrophy. In some cases, LHON is associated with heterogeneous neurological extraocular manifestations and is referred to as “Leber plus disease”; rarely it is associated with a multiple sclerosis (MS)-like syndrome known as Harding disease, but no pediatric extraocular acute spinal onset is reported.Case presentation
We describe the case of a 5-year-old girl carrying the G3460A mtDNA mutation who was referred to clinical examination for bilateral upper and lower limb weakness with no sign of optic neuropathy. Spinal cord MRI showed hyperintense signal alterations in T2-weighted and restricted diffusion in DWI sequences in the anterior portion of the cervical and dorsal spinal cord resembling a spinal cord vascular injury. No association between this mutation and pediatric spinal cord lesions has previously been reported. Alternative diagnostic hypotheses, including infective, ischemic and inflammatory disorders, were not substantiated by clinical and instrumental investigations.Conclusions
Our case reports a novel pediatric clinical manifestation associated with the m.3460G?>?A mtDNA mutation, broadening the clinical spectrum of this disease. Early identification of new cases and monitoring of carriers beginning in childhood is important to prevent neurological deterioration and preserve long-term function.969.
970.
Growth at elevated CO2 leads to down-regulation of photosynthesis and altered response to high temperature in Quercus suber L. seedlings 总被引:1,自引:0,他引:1
Faria T.; Wilkins D.; Besford R. T.; Vaz M.; Pereira J. S.; Chaves M. M. 《Journal of experimental botany》1996,47(11):1755-1761
The effects of growth at elevated CO2 on the response to hightemperatures in terms of carbon assimilation (net photosynthesis,stomatal conductance, amount and activity of Rubisco, and concentrationsof total soluble sugars and starch) and of photochemistry (forexample, the efficiency of excitation energy captured by openphotosystem II reaction centres) were studied in cork oak (Quercussuber L.). Plants grown in elevated CO2 (700 ppm) showed a down-regulationof photosynthesis and had lower amounts and activity of Rubiscothan plants grown at ambient CO2 (350 ppm), after 14 monthsin the greenhouse. At that time plants were subjected to a heat-shocktreatment (4 h at 45C in a chamber with 80% relative humidityand 8001000 mol m2 s1 photon flux density).Growth in a CO2-enriched atmosphere seems to protect cork oakleaves from the short-term effects of high temperature. ElevatedCO2 plants had positive net carbon uptake rates during the heatshock treatment whereas plants grown at ambient CO2 showed negativerates. Moreover, recovery was faster in high CO2-grown plantswhich, after 30 min at 25C, exhibited higher net carbon uptakerates and lower decreases in photosynthetic capacity (Amax aswell as in the efficiency of excitation energy captured by openphotosystem II reaction centres (FvJFm than plants grown atambient CO2. The stomata of elevated CO2 plants were also lessresponsive when exposed to high temperature. Key words: Elevated CO2, temperature, acclimation, photosynthesis, Quercus suber L. 相似文献