Differential effects of nanoselenium doping on healthy and cancerous osteoblasts in coculture on titanium

In the present study, selenium (Se) nanoclusters were grown through heterogeneous nucleation on titanium (Ti) surfaces, a common orthopedic implant material. Normal healthy osteoblasts (bone-forming cells) and cancerous osteoblasts (osteosarcoma) were cultured on the Se-doped surfaces having three different coating densities. For the first time, it is shown that substrates with Se nanoclusters promote normal osteoblast proliferation and inhibit cancerous osteoblast growth in both separate (mono-culture) and coculture experiment. This study suggests that Se surface nanoclusters can be properly engineered to inhibit bone cancer growth while simultaneously promoting the growth of normal bone tissue

A review of symptomatic leg length inequality following total hip arthroplasty

Leg length inequality (LLI) following total hip replacement is a complication which features increasingly in the recent literature. The definition of LLI is complicated by lack of consensus regarding radiological measurement, clinical measurement and the incomplete relationship between LLI and associated symptoms. This paper reviews 79 reports relating to LLI post hip replacement, detailing definitions and classification and highlighting patient populations prone to symptomatic LLI. While there is no universal definition of LLI, there is a broad consensus that less than 10 mm of difference on AP view plain radiographs is clinically acceptable. There are few techniques described that consistently produce a postoperative LLI of less than this magnitude. Where postoperative LLI exists, lengthening appears to cause more problems than shortening. In cases of mild LLI, non-surgical management produces adequate outcomes in the majority of cases, with functional LLI cases doing better than those with true LLI. Operative correction is effective in half of cases, even where nerve palsy is present, and remains an important option of last resort. Poor outcomes in patients with LLI may be minimised if individuals at risk are identified and counselled appropriately

Selenium nanocluster coatings for anti-cancer, anti-bacterial orthopedic applications

Two common causes leading to bone implant failure are: an insufficient bonding between the implant and surrounding bone and infection. Patients with implant failure often undergo revision surgeries which are costly and painful. Moreover, for patients who receive orthopedic implants after cancerous tissue is removed, it would be beneficial to implant an anti-cancer material that can impede the return of cancerous tissue growth that may develop from cancer cells not removed during surgery. Therefore, the objective of this study was to create a coating material that can: (i) promote healthy, normal bone growth, (ii) inhibit bacterial attachment and (iii) impede cancer growth. To achieve that objective, conventional orthopedic implant materials (such as titanium (Ti), stainless steel and ultra high molecular weight polyethylene) were coated with selenium (Se) nanoclusters. Different coating densities were achieved by varying Se concentration in the reaction mixture. For the first time, Se nanocluster coatings were shown to enhance healthy osteoblast (bone-forming cell) and inhibit cancerous osteoblast proliferation in either separate-culture experiments or co-culture experiments. S. epidermidis (one of the leading bacteria that infect implants) functions were inhibited on materials coated with Se-nanoclusters compared to uncoated materials. Therefore, a new orthopedic implant coating material is introduced here that may be ideal for promoting bone growth and inhibiting cancer and bacteria growth

Selenium nanocluster coatings for anti-cancer orthopedic applications

There are currently no orthopedic materials which are made to prevent either the occurrence or reoccurrence of cancer. Due to the above, the objective of this study was to create a new biomaterial which can both restore bone and, at the same time, prevent cancer growth at the implant interface. In the present study, three types of surfaces with different surface densities were prepared. Competitive cell co-culture studies showed promoted growth of healthy bone cells and inhibited growth of cancerous cells when they were co-seeded on high dose selenium (Se) coated titanium (Ti) substrates. Thus, this study provided for the first time a material to the orthopedic community which may inhibit bone cancer growth and promote healthy bone growth

Increased osteoblast adhesion on nano structured selenium-a promising material for orthopedic applications

Metallic bone implants possess numerous problems limiting their efficacy, such as poor osseointegration, stress shielding, and corrosion under in vivo environments. In addition, these materials were not originally developed to simultaneously serve as an orthopedic implant and treat bone cancer (for which some patients require an orthopedic implant). The objective of this study was to investigate the potential of selenium as a bone implant material to prevent bone cancer from re-occurring and support new healthy bone growth. For this, selenium (spherical or semispherical shots) was pressed into compacts and then etched using NaOH to obtain various surface structures ranging from the micron, sub micron to nano scales. Elemental selenium was also coated on titanium substrates at different coverage levels using selenium salt reduction by glutathione. Through these etching and coating techniques, biologically-inspired nano surface roughness values were created on selenium compacts and selenium coated on titanium to match those of natural bone. Increased osteoblast (bone-forming cells) adhesion was observed on the more rough selenium compacts and on titanium substrates with higher levels of selenium coverage. In this manner, this study suggests a promising future for nanostructured selenium in orthopedic applications involving bone cancer treatmen

Novel anti-cancer, anti-bacterial coatings for biomaterial applications: Selenium nanoclusters

Two common problems with implantation after cancerous tumor resection are cancer recurrence and bacteria infection at the implant site. Tumor resection surgery sometimes can not remove all the cancerous cells, thus, cancer can return after implantation. In addition, bacteria infection is one of the leading causes of implant failure. Therefore, it is desirable to have anti-cancer and anti-bacterial molecules which both rapidly (for anti-infection purposes) and continuously (for anti-cancer purposes) are available at the implant site following implantation. Therefore, the objective of the present in vitro study was to create a multi-functional coating for anti-cancer and anti-bacterial orthopedic implant applications. Elemental selenium was chosen as the biologically active agent in this effort because of its known chemopreventive and anti-bacterial properties. To achieve that objective, titanium (Ti), a conventional orthopedic implant material was coated with selenium (Se) nanoclusters. Different coating densities were achieved by varying Se concentration in the reaction mixture. Titanium substrates coated with Se nanoclusters were shown to enhance healthy osteoblast (bone-forming cell) and inhibit cancerous osteoblast proliferation in co-culture experiments. Functions of S. epidermidis (one of the leading bacteria that infect implants) were inhibited on Ti coated with Se-nanoclusters compared to uncoated materials. Thus, this study provided for the first time a coating material (selenium nanoclusters) to the biomaterials’ community to promote healthy bone cells’ functions, inhibit cancer growth and prevent bacteria infection

Titanium surfaces with adherent selenium nanoclusters as a novel anticancer orthopedic material

Current orthopedic implants have several problems that include poor osseointegration for extended periods of time, stress shielding and wear debris-associated bone cell death. In addition, numerous patients receive orthopedic implants as a result of bone cancer resection, yet current orthopedic materials were not designed to prevent either the occurrence or reoccurrence of cancer. The objective of this <i>in vitro</i> study was to create a new biomaterial which can both restore bone and prevent cancer growth at the implant-tissue interface. Elemental selenium was chosen as the biologically active agent in this study because of its known chemopreventive and chemotherapeutic properties. It was found that when selenite salts were reduced by glutathione in the presence of an immersed titanium substrate, elemental selenium nucleated and grew into adherent, hemispherical nanoclusters that formed a nanostructured composite surface. Three types of surfaces with different selenium surface densities on titanium were fabricated and confirmed by SEM images, AFM, and XPS profiles. Compared to conventional untreated titanium, a high-density selenium-doped surface inhibited cancerous bone cell proliferation while promoting healthy bone cell functions (including adhesion, proliferation, alkaline phosphatase activity and calcium deposition). These findings showed for the first time the potential of selenium nanoclusters as a chemopreventive titanium orthopedic material coating that can also promote healthy bone cell functions

Selenium nanocluster coatings: Transforming current orthopedic materials into inhibiting bone cancer

Selenium (Se) nanoclusters were coated on three different orthopedic materials: Titanium, stainless steel and ultra high molecular weight polyethylene (UHMWPE). There different coating densities were achieved on each type of substrate. The uncoated and coated Ti and SS substrates were then used in experiments with either normal healthy osteoblasts (bone-forming cells) or cancerous osteoblasts (osteosarcoma) or a combination of both. For the first time, it was shown that the substrates coated with Se nanoclusters promoted (or at least maintained) normal osteoblast proliferation and inhibited cancerous osteoblast growth in both separate culture experiments and co-culture experiments. Thus, this study introduced to the orthopedic cancer community for the first time a coating material (Se) which may inhibit bone cancer growth and promote normal bone growth