A fructan-type garlic polysaccharide upregulates immune responses in macrophage cells and in immunosuppressive mice.

The anti-inflammatory effects of plant polysaccharides are well known. However, the stimulatory effects of polysaccharides under immunosuppressive conditions and their link with the polysaccharide structure is underexplored. In this work, the immune modulatory effects of a garlic polysaccharide (GP) are investigated via in vitro and vivo methods.

In vitro calibration and in vivo validation of phenomenological corrosion models for resorbable magnesium-based orthopaedic implants.

Metallic bioresorbable orthopaedic implants based on magnesium, iron and zinc-based alloys that provide rigid internal fixation without foreign-body complications associated with permanent implants have great potential as next-generation orthopaedic devices. Magnesium (Mg) based alloys exhibit excellent biocompatibility. However, the mechanical performance of such implants for orthopaedic applications is contingent on limiting the rate of corrosion in vivo throughout the bone healing process.

Penetration Coefficients of Commercial Nanolimes and a Liquid Mineral Precursor for Pore-Imitating Test Systems-Predictability of Infiltration Behavior.

Nanolimes have been commercially available for over a decade as a remineralization agent for natural stone to combat deterioration. While they have been applied successfully and studied extensively, their penetration abilities in different materials have not yet been readily quantifiable in situ and in real time. Using two transparent pore-imitating test systems (acrylic glass (PMMA) and polydimethylsiloxane (PDMS)) and light microscopy, the penetration coefficients (s) of two nanolimes (CaLoSiL (CLS) and Nanorestore Plus (NRP)), as well as their solvents, were determined experimentally in square channels of about 100 µm diameter.

Surgically-induced deformation in biodegradable orthopaedic implant devices.

The biocompatibility and mechanical performance of biodegradable metals (e.g. magnesium, iron, and zinc-based alloys) in orthopaedic-targeted applications are contingent on limiting the rate of corrosion in vivo throughout the bone healing.

modelling of the corrosion of biodegradable magnesium-based biomaterials: modelling approaches, validation and future perspectives.

Metallic biomedical implants based on magnesium, zinc and iron alloys have emerged as bioresorbable alternatives to permanent orthopaedic implants over the last two decades. The corrosion rate of biodegradable metals plays a critical role in controlling the compatibility and functionality of the device in vivo. The broader adoption of biodegradable metals in orthopaedic applications depends on developing in vitro methods that accurately predict the biodegradation behaviour in vivo.

Flow cytometry-based high-throughput RNAi screening for miRNAs regulating MHC class II HLA-DR surface expression.

HLA-DR isotype is a MHC-II cell-surface receptor found on APCs and plays a key role in initiating immune responses. In severely immunocompromised patients with conditions like sepsis, the number of HLA-DR molecules expressed on leukocytes is considered to correlate with infectious complications and patients' probability of survival. The underlying regulatory mechanisms of HLA-DR expression remain largely unknown.

Randomized investigation of the bioavailability of fluoride in saliva after administration of sodium fluoride, amine fluoride and fluoride containing bioactive glass dentifrices.

Objectives: Bioactive glasses which degrade in aqueous solutions may release bioactive ions such as fluoride (F) and support fluoride bioavailability in saliva. We investigated how these effects would be apparent in an in vivo experimental trial after toothbrushing in comparison with sodium fluoride and amine fluoride.

Material And Methods: In this single-center, randomized, parallel in vivo trial with a three strata block design, where healthy subjects were randomly assigned into three groups.

Nanostructured cellulose-xyloglucan blends via ionic liquid/water processing.

In this work, the properties of cellulose (CE)/xyloglucan (XG) biopolymer blends are investigated, taking inspiration from the outstanding mechanical properties of plant cell walls. CE and XG were first co-solubilized in an ionic liquid, 1-ethyl-3-methylimidazolium acetate, in order to blend these biopolymers with a varying CE:XG ratio. The biopolymers were then regenerated together using water to produce solid blends in the form of films.

Complementary characterization data in support of uniaxially aligned electrospun nanocomposites based on a model PVOH-epoxy system.

This paper presents complementary data corresponding to characterization tests done for our research article entitled "Uniaxially aligned electrospun fibers for advanced nanocomposites based on a model PVOH-epoxy system" (Karimi et al., 2016) [1]. Poly(vinyl alcohol) and epoxy resin were selected as a model system and the effect of electrospun fiber loading on polymer properties was examined in conjunction with two manufacturing methods.

Topologically ordered magnesium-biopolymer hybrid composite structures.

Magnesium and its alloys are intriguing as possible biodegradable biomaterials due to their unique combination of biodegradability and high specific mechanical properties. However, uncontrolled biodegradation of magnesium during implantation remains a major challenge in spite of the use of alloying and protective coatings. In this study, a hybrid composite structure of magnesium metal and a biopolymer was fabricated as an alternative approach to control the corrosion rate of magnesium.

Magnesium biomaterials for orthopedic application: a review from a biological perspective.

Magnesium (Mg) has a long history of investigation as a degradable biomaterial. Physicians first began using Mg for biomedical applications in the late 19th century. Experimentation continued with varying levels of success until the mid-20th century when interest in the metal waned.

The in vitro and in vivo evaluation of the biocompatibility of Mg alloys.

Magnesium (Mg) and its alloys are being widely investigated for their potential use as resorbable biomaterials for orthopaedic applications. However, the natural corrosion of the metals results in potentially harmful perturbations to the physiological environment, which requires a comprehensive understanding of their biocompatibility. Currently, most investigations proceed directly from in vitro biocompatibility studies to intraosseous implantation.

Monetite and brushite coated magnesium: in vivo and in vitro models for degradation analysis.

The use of magnesium (Mg) as a biodegradable metallic replacement of permanent orthopaedic materials is a current topic of interest and investigation. The appropriate biocompatibility, elastic modulus and mechanical properties of Mg recommend its suitability for bone fracture fixation. However, the degradation rates of Mg can be rapid and unpredictable resulting in mass hydrogen production and potential loss of mechanical integrity.

Electronic structure tuning of diamondoids through functionalization.

We investigated the changes in electronic structures induced by chemical functionalization of the five smallest diamondoids using valence photoelectron spectroscopy. Through the variation of three parameters, namely functional group (thiol, hydroxy, and amino), host cluster size (adamantane, diamantane, triamantane, [121]tetramantane, and [1(2,3)4]pentamantane), and functionalization site (apical and medial) we are able to determine to what degree these affect the electronic structures of the overall systems. We show that unlike, for example, in the case of halobenzenes, the ionization potential does not show a linear dependence on the electronegativity of the functional group.

Growth of calcium phosphates on magnesium substrates for corrosion control in biomedical applications via immersion techniques.

Magnesium (Mg) has been suggested as a revolutionary biodegradable replacement for current permanent metals used in orthopedic applications. Current investigations concentrate on the control of the corrosion rate to match bone healing. Calcium phosphate coatings have been a recent focus of these investigations through various coating protocols.

Solvent infusion processing of all-cellulose composite materials.

Continuous fibre-reinforced all-cellulose composite (ACC) laminates were produced in the form of a dimensionally thick (>1 mm) laminate using an easy-to-use processing pathway termed solvent infusion processing (SIP) from a rayon (Cordenka™) textile using the ionic liquid 1-butyl-3-methylimidazolium acetate. SIP facilitates the infusion of a solvent through a dry cellulose fibre preform with the aim of partially dissolving the outer surface of the cellulose fibres. The dissolved cellulose is then regenerated by solvent exchange to form a matrix phase in situ that acts to bond together the undissolved portion of the fibres.

On the role of surface roughness in the corrosion of pure magnesium in vitro.

The relationship between surface roughness and degradation behavior in magnesium (Mg) biomaterials is still a controversial issue. This study aims to clarify the relationship between surface roughness and corrosion rate of pure Mg. Pure Mg samples with surface roughness values (Ra) of 0.

Magnesium alloys: predicting in vivo corrosion with in vitro immersion testing.

Magnesium (Mg) and its alloys have been proposed as degradable replacements to commonly used orthopedic biomaterials such as titanium alloys and stainless steel. However, the corrosion of Mg in a physiological environment remains a difficult characteristic to accurately assess with in vitro methods. The aim of this study was to identify a simple in vitro immersion test that could provide corrosion rates similar to those observed in vivo.

Buffer-regulated biocorrosion of pure magnesium.

Magnesium (Mg) alloys are being actively investigated as potential load-bearing orthopaedic implant materials due to their biodegradability in vivo. With Mg biomaterials at an early stage in their development, the screening of alloy compositions for their biodegradation rate, and hence biocompatibility, is reliant on cost-effective in vitro methods. The use of a buffer to control pH during in vitro biodegradation is recognised as critically important as this seeks to mimic pH control as it occurs naturally in vivo.

Chiral index dependence of the G+ and G- Raman modes in semiconducting carbon nanotubes.

Raman spectroscopy on the radial breathing mode is a common tool to determine the diameter d or chiral indices (n,m) of single-wall carbon nanotubes. In this work we present an alternative technique to determine d and (n,m) based on the high-energy G(-) mode. From resonant Raman scattering experiments on 14 highly purified single chirality (n,m) samples we obtain the diameter, chiral angle, and family dependence of the G(-) and G(+) peak position.

Assessing the corrosion of biodegradable magnesium implants: a critical review of current methodologies and their limitations.

Magnesium (Mg) and its alloys have been intensively studied as biodegradable implant materials, where their mechanical properties make them attractive candidates for orthopaedic applications. There are several commonly used in vitro tests, from simple mass loss experiments to more complex electrochemical methods, which provide information on the biocorrosion rates and mechanisms. The various methods each have their own unique benefits and limitations.

Amyloid fibrils as functionalizable components of nanocomposite materials.

Amyloid fibrils are a form of protein nanofiber that show promise as components of multifunctional bionanomaterials. In this work, native bovine insulin and bovine insulin that had been previously converted into amyloid fibrils were combined with poly(vinyl alcohol) (PVOH) via solution casting to determine the effect of fibrillization on the thermomechanical properties of the resulting composite. The synthesis method was found to preserve the amyloid fibril structure and properties of the resulting fibril-PVOH composite were investigated.

Dynamic mechanical analysis and biomineralization of hyaluronan-polyethylene copolymers for potential use in osteochondral defect repair.

Treatment options for damaged articular cartilage are limited due to its lack of vasculature and its unique viscoelastic properties. This study was the first to fabricate a hyaluronan (HA)-polyethylene copolymer for potential use in the replacement of articular cartilage and repair of osteochondral defects. Amphiphilic graft copolymers consisting of HA and high-density polyethylene (HA-co-HDPE) were fabricated with 10, 28 and 50 wt.

In-vitro dissolution of magnesium-calcium binary alloys: clarifying the unique role of calcium additions in bioresorbable magnesium implant alloys.

A systematic investigation of a series of magnesium-calcium binary alloys is presented to reveal the influence of increasing calcium (Ca) additions on the in vitro degradation of magnesium (Mg). Because of its prevalence in structural tissues, Ca is among the most biologically viable additions to orthopedic-intended Mg-based biomaterials. Hence, a fundamental electrochemical study of Ca additions to Mg biomaterials is essential to its continued role as an alloying addition.