Applying the Techniques of Materials Science towards an Understanding of the Process of Canine Intervertebral Disc Degeneration.

Intervertebral disc degeneration in dogs occurs in an accelerated way and involves calcification, which is associated with disc herniation or extrusion. The degenerative process is complex and involves the transformation of collagen fibres, loss of proteoglycans and notochord cells and a reduction in water content; however, how these processes are linked to future disc extrusion remains unknown. We have employed techniques including Fourier Transform Infra-red Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Uniaxial Compression Loading and Atomic Force Microscopy (AFM) in an attempt to gain a greater understanding of the degenerative process and its consequences on the physical properties of the disc.

Urinary Silicon Excretion in Relation to Lactation and Bone Mineral Density - a Longitudinal Study Post-partum.

Silicon (Si) may be a mineral beneficial for bone health. Pregnancy and lactation have major impacts on maternal bone metabolism as bone minerals, including calcium (Ca), are required for growth of the foetus and for milk production. Like urinary Ca excretion, Si excretion has been reported to be high in pregnant women, but there are no data post-partum and during lactation.

Testicular germ cell tumour cells release microRNA-containing extracellular vesicles that induce phenotypic and genotypic changes in cells of the tumour microenvironment.

Malignant germ-cell-tumours (GCTs) are characterised by microRNA (miRNA/miR-) dysregulation, with universal over-expression of miR-371~373 and miR-302/367 clusters regardless of patient age, tumour site, or subtype (seminoma/yolk-sac-tumour/embryonal carcinoma). These miRNAs are released into the bloodstream, presumed within extracellular-vesicles (EVs) and represent promising biomarkers. Here, we comprehensively examined the role of EVs, and their miRNA cargo, on (fibroblast/endothelial/macrophage) cells representative of the testicular GCT (TGCT) tumour microenvironment (TME).

Heavy metal contamination in pristine environments: lessons from the Juan Fernandez fur seal ().

Heavy metals, including mercury (Hg) and cadmium (Cd), occur naturally or anthropogenically and are considered toxic to the environment and human health. However, studies on heavy metal contamination focus on locations close to industrialized settlements, while isolated environments with little human activity are often ignored due to perceived low risk. This study reports heavy metal exposure in Juan Fernandez fur seals (JFFS), a marine mammal endemic to an isolated and relatively pristine archipelago off the coast of Chile.

Formulation of Metal-Organic Framework-Based Drug Carriers by Controlled Coordination of Methoxy PEG Phosphate: Boosting Colloidal Stability and Redispersibility.

Metal-organic framework nanoparticles (nanoMOFs) have been widely studied in biomedical applications. Although substantial efforts have been devoted to the development of biocompatible approaches, the requirement of tedious synthetic steps, toxic reagents, and limitations on the shelf life of nanoparticles in solution are still significant barriers to their translation to clinical use. In this work, we propose a new postsynthetic modification of nanoMOFs with phosphate-functionalized methoxy polyethylene glycol (mPEG-PO) groups which, when combined with lyophilization, leads to the formation of redispersible solid materials.

Inhibitory effects of orthosilicic acid on osteoclastogenesis in RANKL-stimulated RAW264.7 cells.

Numerous studies have reported on the positive effects of silicon (Si) on bone metabolism, particularly on the stimulatory effects of Si on osteoblast cells and on bone formation. Inhibitory effects of Si on osteoclast formation and bone resorption have also been demonstrated in vitro and are suggested to be mediated indirectly via stromal and osteoblast cells. Direct effects of Si on osteoclasts have been less studied and mostly using soluble Si, but no characterisation of the Si treatment solutions are provided.

Unexplored nutritive potential of tomato to combat global malnutrition.

Tomato, a widely consumed vegetable crop, offers a real potential to combat human nutritional deficiencies. Tomatoes are rich in micronutrients and other bioactive compounds (including vitamins, carotenoids, and minerals) that are known to be essential or beneficial for human health. This review highlights the current state of the art in the molecular understanding of the nutritional aspects, conventional and molecular breeding efforts, and biofortification studies undertaken to improve the nutritional content and quality of tomato.

Gastrointestinal Absorption and Toxicity of Nanoparticles and Microparticles: Myth, Reality and Pitfalls explored through Titanium Dioxide.

Daily oral exposure to vast numbers (>10/adult/day) of micron or nano-sized persistent particles has become the norm for many populations. Significant airborne particle exposure is deleterious, so what about ingestion? Titanium dioxide in food grade form (fgTiO) , which is an additive to some foods, capsules, tablets and toothpaste, may provide clues. Certainly, exposed human populations accumulate these particles in specialised intestinal cells at the base of large lymphoid follicles (Peyer's patches) and it's likely that a degree of absorption goes beyond this- i.

Soluble silica stimulates osteogenic differentiation and gap junction communication in human dental follicle cells.

Several studies have indicated that dietary silicon (Si) is beneficial for bone homeostasis and skeletal health. Furthermore, Si-containing bioactive glass biomaterials have positive effects on bone regeneration when used for repair of bone defects. Si has been demonstrated to stimulate osteoblast differentiation and bone mineralisation in vitro.

Physiological silicon incorporation into bone mineral requires orthosilicic acid metabolism to SiO.

Under physiological conditions, the predominant form of bioavailable silicon (Si) is orthosilicic acid (OSA). In this study, given Si's recognized positive effect on bone growth and integrity, we examined the chemical form and position of this natural Si source in the inorganic bone mineral hydroxyapatite (HA). X-ray diffraction (XRD) of rat tibia bone mineral showed that the mineral phase was similar to that of phase-pure HA.

A Murine Oral-Exposure Model for Nano- and Micro-Particulates: Demonstrating Human Relevance with Food-Grade Titanium Dioxide.

Human exposure to persistent, nonbiological nanoparticles and microparticles via the oral route is continuous and large scale (10 -10 particles per day per adult in Europe). Whether this matters or not is unknown but confirmed health risks with airborne particle exposure warns against complacency. Murine models of oral exposure will help to identify risk but, to date, lack validation or relevance to humans.

Interleukin-33 Signaling Controls the Development of Iron-Recycling Macrophages.

Splenic red pulp macrophages (RPMs) contribute to erythrocyte homeostasis and are required for iron recycling. Heme induces the expression of SPIC transcription factor in monocyte-derived macrophages and promotes their differentiation into RPM precursors, pre-RPMs. However, the requirements for differentiation into mature RPMs remain unknown.

Urinary Excretion of Silicon in Men, Non-pregnant Women, and Pregnant Women: a Cross-sectional Study.

Silicon is a trace element found mainly in plant-based food and proposed to be beneficial for bone health. Urinary excretion of Si has been shown to be a surrogate measure of its uptake in the gastrointestinal tract. The objective of this study was to describe and compare the levels of urinary Si excretion, and consequently Si uptake, in Swedish men, non-pregnant women, and pregnant women.

Bone mineral health is sensitively related to environmental cadmium exposure- experimental and human data.

Exposure to cadmium (Cd) is recognised as one of the risk factors for osteoporosis, although critical exposure levels and exact mechanisms are still unknown. Here, we first confirmed that in male Wistar rats challenged orally with 6 different levels of Cd (0.3-10 mg/kg b.

Non-Functionalized Ultrasmall Silica Nanoparticles Directly and Size-Selectively Activate T Cells.

Sub-micron-sized silica nanoparticles, even as small as 10-20 nm in diameter, are well-known for their activation of mononuclear phagocytes. In contrast, the cellular impact of those <10 nm [ i.e.

Silica nanoparticles as sources of silicic acid favoring wound healing in vitro.

There is good evidence that certain silicon-containing materials promote would healing and their common feature is the delivery of orthosilicic acid (Si(OH)) either directly or following metabolism. In this respect, amorphous silica nanoparticles (NP), which dissolve in aqueous environments releasing up to 2mM orthosilicic acid, may be appropriate 'slow release' vehicles for bioactive silicon. Here we studied the impact of silica NP suspensions (primary particles∼10nm) in undersaturated conditions (below 2mM Si) with differing degrees of surface charge and dissolution rate on human dermal fibroblasts (CCD-25SK cells) viability, proliferation and migration in a cellular wound model.

Identification of a mammalian silicon transporter.

Silicon (Si) has long been known to play a major physiological and structural role in certain organisms, including diatoms, sponges, and many higher plants, leading to the recent identification of multiple proteins responsible for Si transport in a range of algal and plant species. In mammals, despite several convincing studies suggesting that silicon is an important factor in bone development and connective tissue health, there is a critical lack of understanding about the biochemical pathways that enable Si homeostasis. Here we report the identification of a mammalian efflux Si transporter, namely Slc34a2 (also termed NaPiIIb), a known sodium-phosphate cotransporter, which was upregulated in rat kidney following chronic dietary Si deprivation.

Adsorption of Amorphous Silica Nanoparticles onto Hydroxyapatite Surfaces Differentially Alters Surfaces Properties and Adhesion of Human Osteoblast Cells.

Silicon (Si) is suggested to be an important/essential nutrient for bone and connective tissue health. Silicon-substituted hydroxyapatite (Si-HA) has silicate ions incorporated into its lattice structure and was developed to improve attachment to bone and increase new bone formation. Here we investigated the direct adsorption of silicate species onto an HA coated surface as a cost effective method of incorporating silicon on to HA surfaces for improved implant osseointegration, and determined changes in surface characteristics and osteoblast cell adhesion.

Silicon and boron differ in their localization and loading in bone.

Silicon and boron share many similarities, both chemically and biochemically, including having similar effects on bone, although their mechanisms of action are not known. Here we compared the loading of silicon and boron into bone, their localization and how they are influenced by age (growth & development), to obtain further clues as to the biological effects of these elements and, especially, to see if they behave the same or not. Bone samples were obtained from two different studies where female Sprague Dawley rats had been maintained on a normal maintenance diet for up to 43 weeks.

Dietary Silicon Deficiency Does Not Exacerbate Diet-Induced Fatty Lesions in Female ApoE Knockout Mice.

Background: Dietary silicon has been positively linked with vascular health and protection against atherosclerotic plaque formation, but the mechanism of action is unclear.

Objectives: We investigated the effect of dietary silicon on 1) serum and aorta silicon concentrations, 2) the development of aortic lesions and serum lipid concentrations, and 3) the structural and biomechanic properties of the aorta.

Methods: Two studies, of the same design, were conducted to address the above objectives.

The decrease in silicon concentration of the connective tissues with age in rats is a marker of connective tissue turnover.

Silicon may be important for bone and connective tissue health. Higher concentrations of silicon are suggested to be associated with bone and the connective tissues, compared with the non-connective soft tissues. Moreover, in connective tissues it has been suggested that silicon levels may decrease with age based upon analyses of human aorta.

Positive association between serum silicon levels and bone mineral density in female rats following oral silicon supplementation with monomethylsilanetriol.

Unlabelled: Observational (epidemiological) studies suggest the positive association between dietary silicon intake and bone mineral density may be mediated by circulating estradiol level. Here, we report the results of a silicon supplementation study in rats that strongly support these observations and suggest an interaction between silicon and estradiol.

Introduction: Epidemiological studies report strong positive associations between dietary silicon (Si) intake and bone mineral density (BMD) in premenopausal women and indicate that the association may be mediated by estradiol.

Silicon balance in human volunteers; a pilot study to establish the variance in silicon excretion versus intake.

Background: Accumulating evidence suggests a role for silicon in optimal connective tissue health. Further proof of its importance/essentiality may be provided by studies involving imposed depletion followed by 29Si challenge to estimate metabolic balance. Prior to conducting these expensive studies, we first established the variance of estimating normal Si excretion versus intake using a single oral dose of typical dietary Si, orthosilicic acid.

High-aluminum-affinity silica is a nanoparticle that seeds secondary aluminosilicate formation.

Despite the importance and abundance of aluminosilicates throughout our natural surroundings, their formation at neutral pH is, surprisingly, a matter of considerable debate. From our experiments in dilute aluminum and silica containing solutions (pH ~ 7) we previously identified a silica polymer with an extraordinarily high affinity for aluminium ions (high-aluminum-affinity silica polymer, HSP). Here, further characterization shows that HSP is a colloid of approximately 2.