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1.
The ab-initio crystal structure solution by powder diffraction data requires great efforts because of the collapse of the experimental information onto the one dimensional 2θ axis of the pattern. Different strategies will be described aiming at improving the process of extraction of the integrated intensities from the experimental pattern in order to make more straightforward the structure solution process by direct methods. Particular attention will be devoted to the EXPO program. Some of its performance will be analysed and results will be shown.  相似文献   
2.
Diabetes mellitus is a group of heterogeneous metabolic disorders characterized by chronic hyperglycaemia mainly due to pancreatic β cell death and/or dysfunction, caused by several types of stress such as glucotoxicity, lipotoxicity and inflammation. Different patho-physiological mechanisms driving β cell response to these stresses are tightly regulated by microRNAs (miRNAs), a class of negative regulators of gene expression, involved in pathogenic mechanisms occurring in diabetes and in its complications. In this review, we aim to shed light on the most important miRNAs regulating the maintenance and the robustness of β cell identity, as well as on those miRNAs involved in the pathogenesis of the two main forms of diabetes mellitus, i.e., type 1 and type 2 diabetes. Additionally, we acknowledge that the understanding of miRNAs-regulated molecular mechanisms is fundamental in order to develop specific and effective strategies based on miRNAs as therapeutic targets, employing innovative molecules.  相似文献   
3.
Multiple sclerosis is characterized by inflammatory demyelination and axonal loss as pathophysiological correlates of relapsing activity and progressive development of clinical disability. The molecular processes involved in this pathogenesis are still unclear as they are quite complex and heterogeneous. In this article we present protein expression analysis of brain and spinal cord tissues from different models of murine experimental autoimmune encephalomyelitis (EAE), the most commonly used animal model for multiple sclerosis. We observed a number of EAE-specific protein expression and PTM differences. Proteome analysis was extended to multiple sclerosis specimens in order to validate the EAE findings. Our findings suggest the regulation of a number of proteins that shed light on the molecular mechanisms of the disease processes taking place in EAE and multiple sclerosis. We found consistent modulation of proteins including serum amyloid P component, sirtuin 2, dihydropyrimidinase-related protein family proteins, stathmin 1, creatine kinase B and chloride intracellular channel protein 1. Functional classification of the proteins by database and the literature mining reveals their association with neuronal development and myelinogenesis, suggesting possible disease processes that mediate neurodegeneration.  相似文献   
4.
Abstract

Ciprofloxacin is a drug active against a broad spectrum of aerobic Gram-positive and Gram-negative bacteria, for the therapy of ocular infections. It requires frequent administrations owing to rapid ocular clearance and it is a good candidate for ocular controlled release formulations. The preparation of such drug release systems is still a challenge. Ionic interactions between ciprofloxacin and the polyelectrolytes chondroitin sulfate or lambda carrageenan result in coprecipitates that can act as microparticulate controlled release systems from which the drug is released after being displaced by the medium’s ions. In some formulations, Carbopol was added to improve the mucoadhesive properties. The aim of this research was the study of the influence of the technological parameters of the preparation method of coprecipitates on their particle size, with the goal of achieving particles engineered with a size suitable for the ocular administration. Technological parameters taken into account were: concentration of drug and polymer solutions utilized for the preparation of interaction products, possible use of surfactants (kind and concentration), temperature of the solutions and stirring during the process of preparation of the coprecipitates. Preliminary stability study tests were carried out to further characterize the leader formulation. Particle size in suspensions for ocular drug delivery is a critical parameter influencing the quality of the formulation. The results obtained from this study show that chondroitin sulfate coprecipitates present the best characteristics in terms of particle size suitable for ocular administration. A further improvement of the particle size characteristics has been obtained with the addition of surfactants.  相似文献   
5.
Advances in research have boosted therapy development for congenital disorders of glycosylation (CDG), a group of rare genetic disorders affecting protein and lipid glycosylation and glycosylphosphatidylinositol anchor biosynthesis. The (re)use of known drugs for novel medical purposes, known as drug repositioning, is growing for both common and rare disorders. The latest innovation concerns the rational search for repositioned molecules which also benefits from artificial intelligence (AI). Compared to traditional methods, drug repositioning accelerates the overall drug discovery process while saving costs. This is particularly valuable for rare diseases. AI tools have proven their worth in diagnosis, in disease classification and characterization, and ultimately in therapy discovery in rare diseases. The availability of biomarkers and reliable disease models is critical for research and development of new drugs, especially for rare and heterogeneous diseases such as CDG. This work reviews the literature related to repositioned drugs for CDG, discovered by serendipity or through a systemic approach. Recent advances in biomarkers and disease models are also outlined as well as stakeholders’ views on AI for therapy discovery in CDG.  相似文献   
6.
How do the new building façade components work under real climatic conditions? The question is especially related to the dynamic behaviour of new and complex components such as the ventilated walls, the Phase Change Material, or others that use nano-technologies and aerogels. One of the objectives of the undergoing research activity, named Abitare Mediterraneo, is the evaluation of their thermal behaviour through the use of an outdoor test cell, in order to reproduce under the real external conditions the performance of these components, and consequently define the main thermal parameters such as the attenuation factor and the thermal inertia, characterising the component; moreover, the results will be used to write new algorithms for dynamic simulation tools allowing an appropriate evaluation of the complex behaviour of the whole building at a real scale condition. The new test cell is realised in Florence, Italy. The design starts from the study of the experience of the existing PASSYS test cells, overtaking the main weakness of the building structure and of the heat-flux sensors.  相似文献   
7.
Bioceramics, such as silica-based glasses, are widely used in bone and teeth restoration. Nowadays, the association between nanotechnology and pharmacology is one of the most promising research fields in cancer therapy. The advanced processing methods and new chemical strategies allow the incorporation of drugs within them or on their functionalized surfaces. Bioceramics can act as local drug delivery systems to treat bone and teeth diseases. The present paper reports data related to the development of a pH-stimuli responsive bioactive glass. The glass conjugation with 5-aminofluorescein (5-AF), through a pH-sensitive organic spacer, allows to produce a pH-responsive bioactive biomaterial: when it is exposed to specific pH changes, it can favour the release of 5-AF directly at the target site. 5-AF has been chosen as a simple, low cost, non toxic model to simulate doxorubicin, an anticancer drug. As doxorubicin, 5-AF contains an amino group in its structure in order to form an amide bond with the carboxylic functionalities of the glass. Raman spectroscopy and thermal analysis confirm the glass conjugation of 5-AF by means of an amide bond; the amount of 5-AF loaded was very high (≈65 and 44 wt%). The release tests at two different pH (4.2 and 7.4) show that the amount of released 5-AF is higher at acid pH with respect to physiological one. This preliminary datum evidenced that a pH-sensitive drug delivery system has been developed. The low amount of 5-AF released (<1 wt% of the total 5-AF) is due to the very low solubility of 5-AF in aqueous medium. This disadvantage, may be overcome in a dynamic environment (physiological conditions), where it is possible to obtain a drug release system ensuring an effective therapeutic dose for long times and, at the same time, avoiding the drug toxicity.  相似文献   
8.
ABSTRACT

This paper explores the case of the historic harbour area of Naples, considered highly significant, due to its physical and cultural characteristics, with the aim of reflecting on the contemporary need for building renewed and synergic city–port relations in a sustainable perspective. Focusing on the physical and functional city–port integration, the study investigates Naples harbour planning policy between twentieth and twenty-first centuries in order to identify the limitations of older instruments and to exam the current proposal, finally suggesting perspectives for the future. The analysis highlights the fact that, in the port of Naples, with a landlord governance, the main obstacles to a more inclusive planning policy have been related to land use conflict between on one hand the public interest of the Port Authority and Municipality and the private interest of port operators on the other. In conclusion, the need for city–port plan integration is outlined as a central planning issue so as to combine the economic development of the harbour with social, cultural and ecological themes and to overcome the conflicts between the different actors involved in the complex planning process.  相似文献   
9.
γ-oryzanol (Orz), a steryl ferulate extracted from rice bran layer, exerts a wide spectrum of biological activities. In addition to its antioxidant activity, Orz is often associated with cholesterol-lowering, anti-inflammatory, anti-cancer and anti-diabetic effects. In recent years, the usefulness of Orz has been studied for the treatment of metabolic diseases, as it acts to ameliorate insulin activity, cholesterol metabolism, and associated chronic inflammation. Previous studies have shown the direct action of Orz when downregulating the expression of genes that encode proteins related to adiposity (CCAAT/enhancer binding proteins (C/EBPs)), inflammatory responses (nuclear factor kappa-B (NF-κB)), and metabolic syndrome (peroxisome proliferator-activated receptors (PPARs)). It is likely that this wide range of beneficial activities results from a complex network of interactions and signals triggered, and/or inhibited by its antioxidant properties. This review focuses on the significance of Orz in metabolic disorders, which feature remarkable oxidative imbalance, such as impaired glucose metabolism, obesity, and inflammation.  相似文献   
10.
Understanding flame propagation mechanism and thermal behavior of flammable dusts is of crucial importance, since they strongly affect the flammability and explosion parameters. In a previous work, we found that the volatile point of anthraquinone/nicotinic acid mixtures can be lower than the one of the pure dusts, suggesting a synergistic effect. In this work, thermogravimetric and differential scanning calorimetry analyses of anthraquinone/niacin mixtures were carried out both in open and closed cup, to explain the observed synergistic behavior. FTIR analysis on solid residue and evolved gaseous species showed that the mixtures change compositions during the thermal treatment, without undergoing any chemical transformation. The thermal behavior of dust mixtures reveals the presence of a eutectic point, resulting in a volatiles production at lower temperature and accelerating the flame propagation.  相似文献   
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