Bioinspired Nanofeatured Substrates: Suitable Environment for Bone Regeneration.

Bone mimicking coatings provide a complex microenvironment in which material, through its inherent properties (such as nanostructure and composition), affects the commitment of stem cells into bone lineage and the production of bone tissue regulating factors required for bone healing and regeneration. Herein, a bioactive mineral/biopolymer composite made of calcium phosphate/chitosan and hyaluronic acid (CaP-CHI-HA) was elaborated using a versatile simultaneous spray coating of interacting species. The resulting CaP-CHI-HA coating was mainly constituted of bioactive, carbonated and crystalline hydroxyapatite with 277 ± 98 nm of roughness, 1 μm of thickness, and 2.3 ± 1 GPa of stiffness. After five days of culture, CaP-CHI-HA suggested a synergistic effect of intrinsic biophysical features and biopolymers on stem cell mechanobiology and nuclear organization, leading to the expression of an early osteoblast-like phenotype and the production of bone tissue regulating factors such as osteoprotegerin and vascular endothelial growth factor. More interestingly, amalgamation with biopolymers conferred to the mineral a bacterial antiadhesive property. These significant data shed light on the potential regenerative application of CaP-CHI-HA bioinspired coating in providing a suitable environment for stem cell bone regeneration and an ideal strategy to prevent implant-associated infections.journal article2017 Apr 122017 03 30importe

De Colorando Auro: Medieval colouring techniques researched using modern analytical techniques

The visual appearance of gold and gilding can be influenced in many ways, such as by changing the composition of the gold alloy or the nature of the gilded substrate. A less known medieval technique, reported in historical treatises, is the chemical treatment of the gilded surface itself, after application and burnishing of the gilding. We reporte here results regarding the study of the Holy Lady Shrine of Huy (13th c AD Mosan, Belgium) on which a possible artificial colouration of the gildings was detected. This led to many questions regarding applicable conservation-restoration treatments. Here is an overview of the results obtained, along with a discussion of the methodology that was developed to study this colouration process, also highlighting the necessary complementarity between laboratory and synchrotron-based analytical approaches. The 3-steps methodology proposed in this paper is generic for most cultural heritage problems where the application of ancient surface modification recipes is suspected but where the scarcity of the historical samples does not allow a direct study of such samples.L’aspect visuel de l’or et des dorures peut être modifié de diverses manières, notamment en changeant la composition de l’alliage ou la nature du support doré. Une technique médiévale moins connue, évoquée dans les traités anciens, consiste à provoquer une réaction chimique après application et brunissage de la dorure. Les recherches sur la châsse de Notre-Dame de Huy (art mosan du xiiie siècle) ont révélé une possible coloration artificielle des dorures. Cette découverte soulève de nombreuses questions quant aux traitements de conservation-restauration utilisables. Nous présentons ici un exposé sommaire des résultats obtenus ainsi qu’un compte rendu de la méthode mise au point pour étudier ce procédé de coloration, en soulignant la complémentarité indispensable entre les examens de laboratoire et l’analyse par rayonnement synchrotron. Dans les sciences du patrimoine culturel, cette méthode en trois temps concerne la plupart des situations où une recette ancienne semble avoir été employée pour modifier la surface, mais où la rareté des échantillons historiques ne permet pas l’étude directe de sous-échantillons

Consumer Law and Policy Relating to Change of Circumstances Due to the COVID-19 Pandemic

An unprecedented number of consumer problems has been caused by the COVID-19 pandemic, not least with regard to refunds of prepayments and the ability of consumers to keep up their monthly payments under loan and rental agreements. Based on a notion of societal force majeure sketched in this paper, we propose guiding principles in respect of the introduction of moratoria on recurring payments, the use of refunds or vouchers in respect of prepayments, and associated enforcement challenges. This analysis draws on experiences around the globe.Non peer reviewe

Оцінка якості життя у вікових першовагітних та вагітних з великим інтергенетичним інтервалом

Проведено изучение показателей качества жизни у 120 возрастных первобеременных и 240 беременных с большим интергенетическим интервалом с использованием опросника SF-36 Health Status Survey, разработанного The Health Institute, New England Medical Center, Boston, USA. Исследование показало, что пациентки обеих групп имеют низкие показатели качества жизни. При сравнении большинство изучаемых параметров оценки качества жизни в обследованных группах не отличались, однако у пациенток с большим интергенетическим интервалом – достоверно выше оценка социальной роли и энергетичности. Оценка качества жизни у возрастных первобеременных и беременных с большим интергенетическим интервалом является важным сегментом наблюдения во время беременности, который оценивает перспективы развития беременности в психологическом, физическом и социальном аспектах.A study of the life quality of 120 over-age primigravidas and of 240 women with a large intergenetic interval has been carried out using the questionnaire SF-36 Health Status Survey developed by The Health Institute, New England Medical Center, Boston, USA. This research has shown that the patients in the both groups have a low quality of life. The major part of the life quality parameters were the same in the both groups, however, in patients with a large interval between births the values of the social role and the energy level were significantly higher. The life quality of over-age primigravidas and pregnant women with a large interval between successive births is an important sector of observation during pregnancy, which allows assessing the prospects of pregnancy in the psychological, physical, and social aspects

Self-healing materials for soft-matter machines and electronics

The emergence of soft machines and electronics creates new opportunities to engineer robotic systems that are mechanically compliant, deformable, and safe for physical interaction with the human body. Progress, however, depends on new classes of soft multifunctional materials that can operate outside of a hard exterior and withstand the same real-world conditions that human skin and other soft biological materials are typically subjected to. As with their natural counterparts, these materials must be capable of self-repair and healing when damaged to maintain the longevity of the host system and prevent sudden or permanent failure. Here, we provide a perspective on current trends and future opportunities in self-healing soft systems that enhance the durability, mechanical robustness, and longevity of soft-matter machines and electronics

Contribution of Fluorescence Techniques in Determining the Efficiency of the Non-thermal Plasma Treatment

We have recently developed a non-thermal plasma (NTP) equipment intended to sterilize fragile medical devices and maintain the sterile state of items downstream the treatment. With traditional counts on agar plate a six log reduction of Staphylococcus aureus viability was obtained within 120 min of O2, Ar, or N2 NTP treatments. However to determine the best NTP process, we studied the different physiological states of S. aureus by flow cytometry (FC) and confocal laser scanning microscopy (CLSM) focusing on the esterasic activity and membrane integrity of the bacteria. Two fluorochromes, 5-(and-6)-carboxy-2′,7′-dichlorofluorescein diacetate and propidium iodide were used in order to distinguish three sub-populations: metabolically active, permeabilized, and damaged bacteria that can be in the viable but nonculturable state. FC and CLSM highlight that O2 and Ar NTP treatments were the most attractive processes. Indeed, a 5 min of Ar NTP generated a high destruction of the structure of bacteria and a 120 min of O2 NTP treatment led to the higher decrease of the total damaged bacteria population. SEM observations showed that in presence of clusters, bacteria of upper layers are easily altered compared to bacteria in the deeper layers. In conclusion, the plate counting method is not sufficient by itself to determine the best NTP treatment. FC and CLSM represent attractive indicator techniques to select the most efficient gas NTP treatment generating the lowest proportion of viable bacteria and the most debris

Corrosion challenges towards a sustainable society

A global transition towards more sustainable, affordable and reliable energy systems is being stimulated by the Paris Agreement and the United Nation's 2030 Agenda for Sustainable Development. This poses a challenge for the corrosion industry, as building climate-resilient energy systems and infrastructures brings with it a long-term direction, so as a result the long-term behaviour of structural materials (mainly metals and alloys) becomes a major prospect. With this in mind "Corrosion Challenges Towards a Sustainable Society" presents a series of cases showing the importance of corrosion protection of metals and alloys in the development of energy production to further understand the science of corrosion, and bring the need for research and the consequences of corrosion into public and political focus. This includes emphasis on the limitation of greenhouse gas emissions, on the lifetime of infrastructures, implants, cultural heritage artefacts, and a variety of other topics

A Rapid and Simple Procedure for the Establishment of Human Normal and Cancer Renal Primary Cell Cultures from Surgical Specimens

The kidney is a target organ for the toxicity of several xenobiotics and is also highly susceptible to the development of malignant tumors. In both cases, in vitro studies provide insight to cellular damage, and represent adequate models to study either the mechanisms underlying the toxic effects of several nephrotoxicants or therapeutic approaches in renal cancer. The development of efficient methods for the establishment of human normal and tumor renal cell models is hence crucial. In this study, a technically simple and rapid protocol for the isolation and culture of human proximal tubular epithelial cells and human renal tumor cells from surgical specimens is presented. Tumor and normal tissues were processed by using the same methodology, based on mechanical disaggregation of tissue followed by enzymatic digestion and cell purification by sequential sieving. The overall procedure takes roughly one hour. The resulting cell preparations have excellent viabilities and yield. Establishment of primary cultures from all specimens was achieved successfully. The origin of primary cultured cells was established through morphological evaluation. Normal cells purity was confirmed by immunofluorescent staining and reverse transcription-polymerase chain reaction analysis for expression of specific markers