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91.
Tiziana Di Chiara Alessandro Del Cuore Mario Daidone Stefania Scaglione Rosario Luca Norrito Maria Grazia Puleo Rosario Scaglione Antonio Pinto Antonino Tuttolomondo 《International journal of molecular sciences》2022,23(5)
There is growing evidence that hypertension is the most important vascular risk factor for the development and progression of cardiovascular and cerebrovascular diseases. The brain is an early target of hypertension-induced organ damage and may manifest as stroke, subclinical cerebrovascular abnormalities and cognitive decline. The pathophysiological mechanisms of these harmful effects remain to be completely clarified. Hypertension is well known to alter the structure and function of cerebral blood vessels not only through its haemodynamics effects but also for its relationships with endothelial dysfunction, oxidative stress and inflammation. In the last several years, new possible mechanisms have been suggested to recognize the molecular basis of these pathological events. Accordingly, this review summarizes the factors involved in hypertension-induced brain complications, such as haemodynamic factors, endothelial dysfunction and oxidative stress, inflammation and intervention of innate immune system, with particular regard to the role of Toll-like receptors that have to be considered dominant components of the innate immune system. The complete definition of their prognostic role in the development and progression of hypertensive brain damage will be of great help in the identification of new markers of vascular damage and the implementation of innovative targeted therapeutic strategies. 相似文献
92.
Paola Maura Tricarico Donatella Mentino Aurora De Marco Cecilia Del Vecchio Sabino Garra Gerardo Cazzato Caterina Foti Sergio Crovella Giuseppe Calamita 《International journal of molecular sciences》2022,23(7)
The skin is the largest organ of the human body, serving as an effective mechanical barrier between the internal milieu and the external environment. The skin is widely considered the first-line defence of the body, with an essential function in rejecting pathogens and preventing mechanical, chemical, and physical damages. Keratinocytes are the predominant cells of the outer skin layer, the epidermis, which acts as a mechanical and water-permeability barrier. The epidermis is a permanently renewed tissue where undifferentiated keratinocytes located at the basal layer proliferate and migrate to the overlying layers. During this migration process, keratinocytes undertake a differentiation program known as keratinization process. Dysregulation of this differentiation process can result in a series of skin disorders. In this context, aquaporins (AQPs), a family of membrane channel proteins allowing the movement of water and small neutral solutes, are emerging as important players in skin physiology and skin diseases. Here, we review the role of AQPs in skin keratinization, hydration, keratinocytes proliferation, water retention, barrier repair, wound healing, and immune response activation. We also discuss the dysregulated involvement of AQPs in some common inflammatory dermatological diseases characterised by skin barrier disruption. 相似文献
93.
Polyethylene-based ionomers, due to the presence of ionic aggregates, display a time-dependent crystalline morphology if submitted to thermal treatments. As a consequence gas permeability, which is strongly affected by physical morphology, is also found to be time dependent in previously thermally treated ionomer samples. The effect of sample exposure at 65°C and of successive ageing at 35°C on gas transmission properties of three different ethylene– acrylic acid ionomers (characterized by a different amount of acrylic acid groups, percentage of neutralization and type of counterions) has been investigated. In particular the changes in oxygen and carbon dioxide permeabilities due to thermal treatments at 65°C and subsequent ageing at 35°C have been monitored. X-Ray diffraction analysis and differential scanning calorimetry have been used to elucidate these changes in transport properties. 相似文献
94.
Enrique Del Castillo Douglas C. Montgomery 《Quality and Reliability Engineering International》1996,12(3):157-157
The first two tables in Reference 1 are incorrect. Corrected tables are provided below. The errors do not affect the conclusions or the discussion in that paper. 相似文献
95.
Barbara Eleni Rosato Roberta Marra Vanessa DOnofrio Federica Del Giudice Simone Della Monica Achille Iolascon Immacolata Andolfo Roberta Russo 《International journal of molecular sciences》2022,23(3)
Biallelic pathogenic variants in the SEC23B gene cause congenital dyserythropoietic anemia type II (CDA II), a rare hereditary disorder hallmarked by ineffective erythropoiesis, hemolysis, erythroblast morphological abnormalities, and hypo-glycosylation of some red blood cell membrane proteins. Abnormalities in SEC23B, which encodes the homonymous cytoplasmic COPII (coat protein complex II) component, disturb the endoplasmic reticulum to Golgi trafficking and affect different glycosylation pathways. The most harmful complication of CDA II is the severe iron overload. Within our case series (28 CDA II patients), approximately 36% of them exhibit severe iron overload despite mild degree of anemia and slightly increased levels of ERFE (the only erythroid regulator of hepcidin suppression). Thus, we hypothesized a direct role of SEC23B loss-of-function in the pathomechanism of hepatic iron overload. We established a hepatic cell line, HuH7, stably silenced for SEC23B. In silenced cells, we observed significant alterations of the iron status, due to both the alteration in BMP/SMADs pathway effectors and a reduced capability to sense BMP6 stimulus. We demonstrated that the loss-of-function of SEC23B is responsible of the impairment in glycosylation of the membrane proteins involved in the activation of the BMP/SMADs pathway with subsequent hepcidin suppression. Most of these data were confirmed in another hepatic cell line, HepG2, stably silenced for SEC23B. Our findings suggested that the pathogenic mechanism of iron overload in CDA II is associated to both ineffective erythropoiesis and to a specific involvement of SEC23B pathogenic variants at hepatic level. Finally, we demonstrated the ability of SEC23B paralog, i.e., SEC23A, to rescue the hepcidin suppression, highlighting the functional overlap between the two SEC23 paralogs in human hepatic cells. 相似文献
96.
B. Speranza M.R. Corbo A. Conte M. Sinigaglia M.A. Del Nobile 《Journal of food science》2009,74(9):M473-M478
ABSTRACT: The effects of modified atmosphere packaging (MAP) (30:40:30 O2 :CO2 :N2 and 5:95 O2 :CO2 ) on the quality of 4 ready-to-cook seafood products were studied. In particular, the investigation was carried out on hake fillets, yellow gurnard fillets, chub mackerel fillets, and entire eviscerated cuttlefish. Quality assessment was based on microbiological and sensorial indices determination. Both packaging gas mixtures contributed to a considerable slowing down of the microbial and sensorial quality loss of the investigated seafood products. Results showed that sensorial quality was the subindex that limited their shelf life. In fact, based primarily on microbiological results, samples under MAP remained acceptable up to the end of storage (that is, 14 d), regardless of fish specie. On the other hand, results from sensory analyses showed that chub mackerel fillets in MAP were acceptable up to the 6th storage d, whilst hake fillets, yellow gurnard fillets, and entire cuttlefish became unacceptable after 10 to 11 d. However, compared to control samples, an increase in the sensorial shelf life of MAP samples (ranging from about 95% to 250%) was always recorded.
Practical Application: Modified atmosphere packaging (MAP) is an inexpensive and uncomplicated method of extending shelf life of packed seafood. It could gain great attention from the fish industrial sector due to the fact that MAP is a practical and economic technique, realizable by small technical expedients. Moreover, there is great attention from the food industry and retailers to react to the growing demand for convenience food, thus promoting an increase in the assortments of ready-to-cook seafood products. 相似文献
Practical Application: Modified atmosphere packaging (MAP) is an inexpensive and uncomplicated method of extending shelf life of packed seafood. It could gain great attention from the fish industrial sector due to the fact that MAP is a practical and economic technique, realizable by small technical expedients. Moreover, there is great attention from the food industry and retailers to react to the growing demand for convenience food, thus promoting an increase in the assortments of ready-to-cook seafood products. 相似文献
97.
F. J. Sánchez-Velasco C. López Del Prá Luis E. Herranz 《Aerosol science and technology》2013,47(5):349-361
This article summarizes the main results of a bench-scale program focused on experimentally assessing the aerosol retention near the tube breach in a tube bundle. The major variables investigated were particle nature (polydispersed TiO 2 agglomerates vs. solid, monodisperse SiO 2 spheres) and Re D (0.8?2.7· 10 5 ). In addition, comparisons to other data sets provided insights into the particle aerodynamic size effect on retention efficiency. Results showed that particle nature substantially affects aerosol retention in the tube bundle: mass retention efficiency was low for TiO 2 agglomerates (less than 30%) whereas it was much higher for SiO 2 particles (around 85%). Retention efficiency is also affected by Re D : its sensitivity was found to follow a log-normal behavior with a maximum retention attained at Re D near 1· 10 5 . This evolution with Re D was similar for both types of compounds. Particle size also influences retention efficiency: the bigger the TiO2 agglomerates the lower retention efficiency (no data were available for SiO 2 ). Among all these variables, particle nature was noted to have a prime importance for in-bundle retention, whereas Re D and particle aerodynamic size, although also affect retention efficiency, did not play such a key role. In light of the results, the presence of retention-inhibiting mechanisms such as fragmentation, resuspension or bouncing has been discussed. The data recorded will enhance the overall understanding of the governing mechanisms involved and will serve as a database against which compare model predictions. Nevertheless, further experimental data would be desirable to set up a sound database. 相似文献
98.
Leandro Del Moral 《国际水》2013,38(3):333-347
Karezes (qanats), historically vital sources of water for multiple uses in the driest parts of the world, have been deteriorating over the past five decades. This paper provides a review of the global literature on the status and potential of karezes, and offers country case studies for Afghanistan, Iran, Pakistan, and Kingdom of Saudi Arabia. It offers syntheses of key issues, lessons, options and proposed interventions for re-vitalizing the karez systems. The paper identifies criteria for prioritizing karez systems for rehabilitation and outlines key conditions for their effective functioning and sustainability. The paper suggests that the benefits of restoring karez systems to local communities are large and some systems, such as the Ain Zubaida in the Makkah Al-Mukaramah Region, are of global importance. 相似文献
99.
Javier Del SerAuthor Vitae Marja MatinmikkoAuthor VitaeSergio Gil-LópezAuthor Vitae Miia MustonenAuthor Vitae 《Applied Soft Computing》2012,12(2):921-930
This paper gravitates on the spectrum channel allocation problem where each compounding node of a cognitive radio network is assigned a frequency channel for transmission over a given outgoing link, based on optimizing an overall network performance metric dependant on the level of interference among nearby nodes. In this context, genetically inspired algorithms have been extensively used so far for solving this optimization problem in a computationally efficient manner. This work extends previous preliminary research carried out by the authors on the application of the heuristic Harmony Search (HS) algorithm to this scenario by presenting further results and derivations on both HS-based centralized and distributed spectrum allocation techniques. Among such advances, a novel adaptive island-like distributed allocation procedure is presented, which dramatically decreases the transmission rate required for exchanging control traffic among nodes at a quantifiable yet negligible performance penalty. Extensive simulation results executed over networks of increasing size verify, on one hand, that our proposed technique achieves near-optimum spectral channel assignments at a low computational complexity. On the other hand, the obtained results assess that HS vastly outperforms genetically inspired allocation algorithms for the set of simulated scenarios. Finally, the proposed adaptive distributed allocation approach is shown to attain a control traffic bandwidth saving of more than 90% with respect to the naive implementation of a HS-based island allocation procedure. 相似文献
100.