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991.
Marika Lanza Giovanna Casili Alessia Filippone Michela Campolo Irene Paterniti Salvatore Cuzzocrea Emanuela Esposito 《International journal of molecular sciences》2021,22(19)
A breached nasal epithelial barrier plays an important role in driving allergic rhinitis (AR). Corticosteroids remain the standard of care (SoC) but come with side effects, thus alternative safe and effective treatments able to avoid inflammation and restore barrier integrity are needed. The aim of the present study is to evaluate the barrier-forming capacity of a xyloglucan-based nasal spray (XG) and compare its efficacy to several SoC treatments (corticosteroid spray, oral mast-cell stabilizer and oral antihistamine) in reducing allergic responses in addition to its effect when concomitantly administered with an antihistamine. An ovalbumin (OVA)-induced mouse AR model was used. XG shows a significant efficacy in reducing histological damage in AR mice; improves nasal rubbing and histamine-induced hyper-responsiveness. Total and OVA-specific IgE as well as pro-inflammatory cytokines are significantly reduced compared to OVA challenged-mice, with im-proved efficacy when used as an add-on treatment. However, XG reduces mucous secreting cells (PAS-positive) and mucin mRNA expression similar to the corticosteroid-treated mice. XG-spray maintains tight junction protein expression (ZO-1) and conversely decreases HDAC1 significantly; the latter being highly expressed in AR patients. Moreover, the concomitant treatment showed in all of the endpoints a similar efficacy to the corticosteroids. This innovative approach may represent a novel therapeutic strategy for nasal respiratory diseases like AR, reducing undesirable side effects and improving the quality of life in patients. 相似文献
992.
Chiara Platella Rosa Gaglione Ettore Napolitano Angela Arciello Valentina Pirota Filippo Doria Domenica Musumeci Daniela Montesarchio 《International journal of molecular sciences》2021,22(19)
G-quadruplex existence was proved in cells by using both antibodies and small molecule fluorescent probes. However, the G-quadruplex probes designed thus far are structure- but not conformation-specific. Recently, a core-extended naphthalene diimide (cex-NDI) was designed and found to provide fluorescent signals of markedly different intensities when bound to G-quadruplexes of different conformations or duplexes. Aiming at evaluating how the fluorescence behaviour of this compound is associated with specific binding modes to the different DNA targets, cex-NDI was here studied in its interaction with hybrid G-quadruplex, parallel G-quadruplex, and B-DNA duplex models by biophysical techniques, molecular docking, and biological assays. cex-NDI showed different binding modes associated with different amounts of stacking interactions with the three DNA targets. The preferential binding sites were the groove, outer quartet, or intercalative site of the hybrid G-quadruplex, parallel G-quadruplex, and B-DNA duplex, respectively. Interestingly, our data show that the fluorescence intensity of DNA-bound cex-NDI correlates with the amount of stacking interactions formed by the ligand with each DNA target, thus providing the rationale behind the conformation-sensitive properties of cex-NDI and supporting its use as a fluorescent probe of G-quadruplex structures. Notably, biological assays proved that cex-NDI mainly localizes in the G-quadruplex-rich nuclei of cancer cells. 相似文献
993.
994.
This paper discusses the excitation and physical validity of both surface-wave and space-wave leaky modes on microstrip lines. This is done by analyzing the discrete modal spectrum excited by a realistic source on or near an infinite microstrip line. A semi-analytical three-dimensional (3-D) Green's function is used for this purpose, which provides the current excited on the conducting strip due to the source. The 3-D Green's function is in the form of a spectral integration (inverse Fourier transform) in the longitudinal wavenumber plane. The poles of the integrand directly determine the excitation amplitudes of the modes on the structure that are launched by the source. The integrand also has different types of branch points, and the location of the poles on the various Riemann sheets is used to determine the physical significance of the leaky modes. Although the theory presented here is illustrated for a microstrip line, the conclusions apply in general to open printed-circuit structures 相似文献
995.
A novel light water reactor design called the AP600 has been proposed by the Westinghouse Electric Corporation. In the evaluation of this plant’s behavior during a small break loss of coolant accident (LOCA), the crucial transition to low pressure, long-term cooling is marked by the injection of the gravitationally driven flow from the in-containment refueling water storage tank (IRWST). The onset of this injection is characterized by intermittency in the IRWST flow. This happens at a time when the reactor vessel reaches its minimum inventory. Therefore, it is important to understand and scale the behavior of the integral experimental test facilities during this portion of the transient. The explanation is that the periodic liquid drains and refills of the pressurizer are the reason for the intermittent behavior. The momentum balance for the surge line yields the nondimensional parameter controlling this process. Data from one of the three experimental facilities represent the phenomena well at the prototypical scale. The impact of the intermittent IRWST injection on the safe plant operation is assessed and its implications are successfully resolved. The oscillation is found to result from, in effect, excess water in the primary system and it is not of safety significance. 相似文献
996.
The Advanced Information System group of the National Research Council (CNR) Computer Science Department at the Cybernetics Institute has become involved in research concerning hypermedia systems in the field of cultural heritage. This activity takes place within the three-year project “An Environment for a Virtual Hypermedia Factory” (VHF). The European Commission funded the project within the 4th RTD Framework, Information Technologies (Multimedia Systems domain). The project aims mainly to develop an integrated environment equipped with services and applications for producing, archiving, and spreading information about cultural heritage, tourism, and publishing through the Internet. This environment encourages content integration by stimulating cooperation among information providers in different but correlated knowledge domains. The paper discusses the Virtual Hypermedia Factory consortium and platform requirements 相似文献
997.
介绍一种汽车制动力检测仪的研制及工作原理,该仪器由力传感器和单片机系统两大部分组成,是一种性能可靠,价格低廉,操作灵活方便的检测仪器。 相似文献
998.
Beta Bdi Patrick M. Pilz Lilla Mrtha Miriam Lang Ouafa Hamza Mikls Fagyas Petra L. Szab Dietmar Abraham Attila Tth Bruno K. Podesser Attila Kiss Zoltn Papp 《International journal of molecular sciences》2021,22(20)
Post-ischemic left ventricular (LV) remodeling and its hypothetical prevention by repeated remote ischemic conditioning (rRIC) in male Sprague–Dawley rats were studied. Myocardial infarction (MI) was evoked by permanent ligation of the left anterior descending coronary artery (LAD), and myocardial characteristics were tested in the infarcted anterior and non-infarcted inferior LV regions four and/or six weeks later. rRIC was induced by three cycles of five-minute-long unilateral hind limb ischemia and five minutes of reperfusion on a daily basis for a period of two weeks starting four weeks after LAD occlusion. Sham operated animals served as controls. Echocardiographic examinations and invasive hemodynamic measurements revealed distinct changes in LV systolic function between four and six weeks after MI induction in the absence of rRIC (i.e., LV ejection fraction (LVEF) decreased from 52.8 ± 2.1% to 50 ± 1.6%, mean ± SEM, p < 0.05) and in the presence of rRIC (i.e., LVEF increased from 48.2 ± 4.8% to 55.2 ± 4.1%, p < 0.05). Angiotensin-converting enzyme (ACE) activity was about five times higher in the anterior LV wall at six weeks than that in sham animals. Angiotensin-converting enzyme 2 (ACE2) activity roughly doubled in post-ischemic LVs. These increases in ACE and ACE2 activities were effectively mitigated by rRIC. Ca2+-sensitivities of force production (pCa50) of LV permeabilized cardiomyocytes were increased at six weeks after MI induction together with hypophosphorylation of 1) cardiac troponin I (cTnI) in both LV regions, and 2) cardiac myosin-binding protein C (cMyBP-C) in the anterior wall. rRIC normalized pCa50, cTnI and cMyBP-C phosphorylations. Taken together, post-ischemic LV remodeling involves region-specific alterations in ACE and ACE2 activities together with changes in cardiomyocyte myofilament protein phosphorylation and function. rRIC has the potential to prevent these alterations and to improve LV performance following MI. 相似文献
999.
Flavia Gasperi Giovanni Gallerani Andrea Boschetti Franco Biasioli Ambrogio Monetti Elena Boscaini Alfons Jordan Werner Lindinger Salvatore Iannotta 《Journal of the science of food and agriculture》2001,81(3):357-363
Described in this paper is a comparison of results obtained in flavour profiling with two different approaches: classical sensory analysis and a novel instrumental technique. The mozzarella cheese flavour profile of seven different brands has been described by a sensory panel of eight judges. The same brands have been studied by means of proton transfer reaction mass spectrometry (PTR‐MS), a novel technique well suited for detecting volatile organic compounds (VOCs) down to the pptv level in air, without any need for sample concentration or trapping. The PTR mass spectra of the headspace of mozzarella samples held at 36 °C have been compared with the judge panel flavour profile. Multivariate statistical data analysis shows that the two methods perform comparable sample discrimination. Even though several questions are still open (definition of better instrumental parameters, improvements in sampling set‐up, spectral interpretation), the PTR‐MS technique appears to be a very promising method for the instrumental evaluation of the flavour sensory profile of food. This opens up new opportunities both in the control of quality and technological processes as well in the fundamental comprehension of the physiological processes of aroma perception. © 2000 Society of Chemical Industry 相似文献
1000.
Viviana P. Cyras Salvatore Iannace Jos M. Kenny Analía Vzquez 《Polymer Composites》2001,22(1):104-110
Biocomposites were produced using polycaprolactone and starch as matrix, and sisal fibers as reinforcement. The matrix is a biodegradable commercial product called MaterBi‐Z, which is based on a polycaprolactone and starch system. The relationship between processing conditions and properties is reported. An alkaline treatment was performed in order to improve the adhesion and the compatibility of the fiber with the matrix. The effect of the treatment on the tensile properties and morphology was determined. Fiber content enhances the tensile properties of the biodegradable composite. The experimentally observed tensile properties (modulus and tensile strength) of short sisal fiber reinforced MaterBi‐Z matrix composites with different fiber loading are compared with the existing theories of reinforcement. SEM photomicrographs of the fractured composite surfaces are also analyzed. 相似文献