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Pollen grains, with their resilient sporopollenin exine and defined morphologies, have been explored as bio-templates for the synthesis of calcium phosphate minerals, particularly hydroxyapatite (HAp) and β-tricalcium phosphate (TCP). Various pollen morphologies from different plant species (black alder, dandelion, lamb's quarters, ragweed, and stargazer lily) were evaluated. Pollen grains underwent acid washing to remove allergenic material and facilitate subsequent calcification. Ragweed and lamb's quarter pollen grains were chosen as templates for calcium phosphate salts deposition due to their distinct morphologies. The calcification process yielded well-defined spherical hollow particles. The washing step, intended to reduce the protein content, did not significantly affect the final product; thus, justifying the removal of this low-yield step from the synthesis process. Characterisation techniques, including X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermal gravimetric analysis, confirmed the successful calcification of pollen-derived materials, revealing that calcified grains were principally composed of calcium deficient HAp. After calcination, biphasic calcium phosphate composed of HAp and TPC was obtained. This study demonstrated the feasibility of using pollen grains as green and sustainable bio-templates for synthesizing biomaterials with controlled morphology, showcasing their potential in biomedical applications such as drug delivery and bone regeneration. [ABSTRACT FROM AUTHOR]

This study evaluated the use of silica/poly(tetrahydrofuran)/poly(ε-caprolactone) (SiO2/PTHF/PCL-diCOOH) 3D-printed scaffolds, with channel sizes of either 200 (SC-200) or 500 (SC-500) µm, as biomaterials to support the chondrogenesis of sheep bone marrow stem cells (oBMSC), under in vitro conditions. The objective was to validate the potential use of SiO2/PTHF/PCL-diCOOH for prospective in vivo ovine studies. The behaviour of oBMSC, with and without the use of exogenous growth factors, on SiO2/PTHF/PCL-diCOOH scaffolds was investigated by analysing cell attachment, viability, proliferation, morphology, expression of chondrogenic genes (RT-qPCR), deposition of aggrecan, collagen II, and collagen I (immunohistochemistry), and quantification of sulphated glycosaminoglycans (GAGs). The results showed that all the scaffolds supported cell attachment and proliferation with upregulation of chondrogenic markers and the deposition of a cartilage extracellular matrix (collagen II and aggrecan). Notably, SC-200 showed superior performance in terms of cartilage gene expression. These findings demonstrated that SiO2/PTHF/PCL-diCOOH with 200 µm pore size are optimal for promoting chondrogenic differentiation of oBMSC, even without the use of growth factors. [ABSTRACT FROM AUTHOR]

Large bone reconstruction following trauma poses significant challenges for reconstructive surgeons, leading to a healthcare burden for health systems, long-term pain for patients, and complex disorders such as infections that are difficult to resolve. The use of bone substitutes is suboptimal for substantial bone loss, as they induce localized atrophy and are generally weak, and unable to support load. A combination of strong polycaprolactone (PCL)-based scaffolds, with an average channel size of 330 µm, enriched with 20% w/w of hydroxyapatite (HA), β-tricalcium phosphate (TCP), or Bioglass 45S5 (Bioglass), has been developed and tested for bone regeneration in a critical-size ovine femoral condyle defect model. After 6 weeks, tissue ingrowth was analyzed using X-ray computed tomography (XCT), Backscattered Electron Microscopy (BSE), and histomorphometry. At this point, all materials promoted new bone formation. Histological analysis showed no statistical difference among the different biomaterials (p > 0.05), but PCL-Bioglass scaffolds enhanced bone formation in the center of the scaffold more than the other types of materials. These materials show potential to promote bone regeneration in critical-sized defects on load-bearing sites. [ABSTRACT FROM AUTHOR]

Background: Perspective taking, defined as the aptitude to understand the cognitive, affective, and visual point of view of others, represents a fundamental social ability for the development of socio‐cognitive and affective skills. Aims: The aim of the present study was to evaluate the possibility of promoting perspective taking in typically developmental preschoolers using an evidence‐based training procedure. Sample and Method: The research used a pre‐test/post‐test quasi‐experimental design in which 206 typically developmental preschoolers (104 males and 102 females) were categorized into the experimental or the control group. In order to try to improve perspective taking, we proposed an evidence‐based ecological intervention inside the kindergarten in which children, in small groups, were involved in activities such as storytelling, discussion, drawing, and dramatization. We measured the perspective taking ability through several tests and prosocial behaviour through repeated ecological non‐participant observations both before and after the training. The training, which lasted 15 days, was subdivided into nine different sessions, each lasting 45 min, and involved small groups of 6–7 children. Before and after the training, each child completed nine perspective taking tasks (three tasks for each perspective taking dimension) and was observed three times, each one for 45 min, on different days. Results: Results showed a significant increase in perspective taking scores after training in the experimental condition relative to the control condition, supporting the possibility of promoting perspective taking ability in preschoolers. An increase in prosocial behaviour after training was also observed in the experimental group as compared with the control group. Conclusion: In conclusion, these results suggest it is possible to improve perspective taking in preschoolers, also promoting prosocial abilities. [ABSTRACT FROM AUTHOR]

Injuries of bone and cartilage constitute important health issues costing the National Health Service billions of pounds annually, in the UK only. Moreover, these damages can become cause of disability and loss of function for the patients with associated social costs and diminished quality of life. The biomechanical properties of these two tissues are massively different from each other and they are not uniform within the same tissue due to the specific anatomic location and function. In this perspective, tissue engineering (TE) has emerged as a promising approach to address the complexities associated with bone and cartilage regeneration. Tissue engineering aims at developing temporary three-dimensional multicomponent constructs to promote the natural healing process. Biomaterials, such as hydrogels, are currently extensively studied for their ability to reproduce both the ideal 3D extracellular environment for tissue growth and to have adequate mechanical properties for load bearing. This review will focus on the use of two manufacturing techniques, namely electrospinning and 3D printing, that present promise in the fabrication of complex composite gels for cartilage and bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Perspective taking, defined as the ability to take on the visual, cognitive, and affective perspective of others, is considered a highly adaptive skill, vital for the child's social, intellectual, and emotional development. This article provides a critical analysis of scientific psychological literature from 1995 to the present on the main methods of intervention used to promote perspective taking in developmentally typical preschool children (3-5 years). The focus is on different methodological approaches, and how the cognitive and emotional dimensions that make up this capacity have been developed through specific operational procedures, emphasizing their strengths and critical factors. In particular, it focuses on the intervention methods based on three major analytical perspectives, specifically the cognitive approach [Theory of Mind (ToM)], the behaviorist approach [Relational Frame Theory (RFT)], and finally, the socio-constructionist approach, are compared. Analysis of the collected data has revealed that despite some critical yet controversial factors, it is actually possible to teach and improve perspective taking in preschoolers through different methods, applicable in different contexts and dependent on the involvement of significant adults, such as parents and educators. [ABSTRACT FROM AUTHOR]

Over the past few decades, bone related disorders have constantly increased. Among all pathological conditions, osteoporosis is one of the most common and often leads to bone fractures. This is a massive burden and it affects an estimated 3 million people only in the UK. Furthermore, as the population ages, numbers are due to increase. In this context, novel biomaterials for bone fracture regeneration are constantly under development. Typically, these materials aim at favoring optimal bone integration in the scaffold, up to complete bone regeneration; this approach to regenerative medicine is also known as tissue engineering (TE). Hydrogels are among the most promising biomaterials in TE applications: they are very flexible materials that allow a number of different properties to be targeted for different applications, through appropriate chemical modifications. The present review will focus on the strategies that have been developed for formulating hydrogels with ideal properties for bone regeneration applications. In particular, aspects related to the improvement of hydrogels' mechanical competence, controlled delivery of drugs and growth factors are treated in detail. It is hoped that this review can provide an exhaustive compendium of the main aspects in hydrogel related research and, therefore, stimulate future biomaterial development and applications. [ABSTRACT FROM AUTHOR]

Perspective taking, defined as the ability to assume another's perspective, can be considered a multidimensional construct which is composed of three different components: cognitive, visual and affective. This study wanted to verify the possibility of promoting perspective taking in preschoolers using ecological training. The maintenance of children's acquired abilities after six months was also assessed. Subsequently, analyses were conducted to examine if a possible increase in these competences could positively influence prosocial disposition and determine a decrease of aggressiveness. The design was a pre-test/post-test quasi-experimental procedure with independent samples: an experimental and a control group, each one with 30 children aged 3–5. Results showed a significant improvement in most of the investigated areas after the training, confirming the possibility of promoting perspective taking abilities. Moreover, children with greater perspective taking skills were also more inclined to behave in a prosocial way during peer interactions. Furthermore, these changes were persistent at the follow-up session six months later. [ABSTRACT FROM PUBLISHER]

The development of antibacterial resistance imposes the development of novel materials to relieve the burden of infection. Chitosan, a material of natural and sustainable origin, possesses ideal characteristics to translate into a novel biomaterial with antibacterial properties, as it already has these properties and it allows easy and scalable chemical modification to enhance its activity. The aim of the present work was that of producing low molecular weight chitosans that have higher solubility and can remain protonated at physiological pH, thus enhancing the antimicrobial action. This was achieved by reacting acid hydrolysed low molecular weight chitosan with 2-bromoethyleneamine hydrobromide or Fmoc-Lys(Fmoc)-OH to elicit N -(2-ethylamino)-chitosan and N -2(2,6-diaminohexanamide)-chitosan polymers. The latter derivative, CS3H Lys, that was synthesised for the first time, showed superior efficacy against Staphylococcus aureus , supporting further studies for its inclusion in implant coating materials to tackle the burden of orthopaedic implant-associated infections. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this study was to contribute to the reduction of synthetic chemical fungicide application in viticulture by using cyclo(- l -Leu- l -Phe) (cLF) produced by Bacillus subtilis KS1, a candidate for biological control agent. cLF is a diketopiperazine and belongs to the family of 2,5-diketopiperazines. KS1 secreted micromolar levels of cLF into culture medium. Micromolar concentrations of cLF structure-dependently decreased by ∼90% both disease severity and lesion density of downy mildew in grapevine cultivated in a growth chamber. Microscopic observation demonstrated that cLF inhibited Plasmopara viticola haustorium formation by 80% but not zoospore germination on leas disks. Interestingly, millimolar concentrations of cLF induced plant defense response, such as expression of genes encoding chitinase and β-1,3-glucanase, in grapevine leaves through the salicylic acid and jasmonate signaling pathways. We demonstrated that cLF was a weapon against P. viticola infection. Further evaluation of cLF in field trials is required to uncover its inherent characteristics. [ABSTRACT FROM AUTHOR]

In this work, we prepared silver nanowires (AgNWs) via the polyol method in the presence or absence of single wall carbon nanotubes (CNTs) and tested their physicochemical, antibacterial and cytotoxic properties. Results showed that the introduction of CNTs lead to the formation of AgNWs at lower temperature, but the final product characteristics of AgNWs and AgNWs-CNT were not significantly different. AgNWs exhibited antibacterial properties against all the studied bacterial species via the formation of oxygen reactive species (ROS) and membrane damage. Furthermore, AgNWs exhibited a dose-dependent and time-dependent toxicity at concentrations ≥ 10 µg/mL. Fibroblasts appeared to be more resistant than human colorectal adenocarcinoma (Caco-2) and osteoblasts to the toxicity of AgNWs. The cytotoxicity of AgNWs was found to be related to the formation of ROS, but not to membrane damage. Overall, these results suggest that AgNWs are potential antibacterial agents against E. coli, S. aureus, MRSA and S. saprophyticus, but their dosage needs to be adjusted according to the route of administration. [ABSTRACT FROM AUTHOR]

One-dimensional nanostructures, such as silver nanowires (AgNWs), have attracted considerable attention owing to their outstanding electrical, thermal and antimicrobial properties. However, their application in the prevention of infections linked to bone tissue regeneration intervention has not yet been explored. Here we report on the development of an innovative scaffold prepared from chitosan, composite hydroxyapatite and AgNWs (CS-HACS-AgNWs) having both bioactive and antibacterial properties. In vitro results highlighted the antibacterial potential of AgNWs against both gram-positive and gram-negative bacteria. The CS-HACS-AgNWs composite scaffold demonstrated suitable Ca/P deposition, improved gel strength, reduced gelation time, and sustained Ag+ release within therapeutic concentrations. Antibacterial studies showed that the composite formulation was capable of inhibiting bacterial growth in suspension, and able to completely prevent biofilm formation on the scaffold in the presence of resistant strains. The hydrogels were also shown to be biocompatible, allowing cell proliferation. In summary, the developed CS-HACS-AgNWs composite hydrogels demonstrated significant potential as a scaffold material to be employed in bone regenerative medicine, as they present enhanced mechanical strength combined with the ability to allow calcium salts deposition, while efficiently decreasing the risk of infections. The results presented justify further investigations into the potential clinical applications of these materials. [ABSTRACT FROM AUTHOR]