To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Breast cancer (BrCa) is the second commonest cause of cancer-related deaths in women. The metastatic breast cancer exhibits a high affinity to bone, leading to debilitating skeletal complications associated with significant morbidity and poor prognosis. Traditional in vitro and in vivo BrCa bone metastasis models contain many inherent limitations with regards to controllability, reproducibility, and flexibility of design. Thus, the objective of this research is to use a 3D bioprinting system and nanomaterials to recreate a biomimetic and tunable bone model suitable for the effective simulation and study of metastatic BrCa invading and colonizing a bone environment. For this purpose, we designed and 3D printed a series of scaffolds, comprised of a bone microstructure and nano hydroxyapatites (nHA, inorganic nano components in bone). The size and geometry of the bone microstructure was varied with 250 and 150 µm pores, in repeating square and hexagon patterns, for a total of four different pore geometries. 3D bioprinted scaffolds were subsequently conjugated with nHA, using an acetylation chemical functionalization process and then characterized by scanning electron microscope (SEM). SEM imaging showed that our designed microfeatures were printable with the predesigned resolutions described above. Imaging further confirmed that acetylation effectively attached nHA to the surface of scaffolds and induced a nanoroughness. Metastatic BrCa cell 4 h adhesion and 1, 3 and 5 day proliferation were investigated in the bone model in vitro. The cell adhesion and proliferation results showed that all scaffolds are cytocompatible for BrCa cell growth; in particular the nHA scaffolds with small hexagonal pores had the highest cell density. Given this data, it can be stipulated that our 3D printed nHA scaffolds may make effective biomimetic environments for studying BrCa bone metastasis.
Articular cartilage is prone to degeneration and possesses extremely poor self-healing capacity due to its low cell density and absence of blood vessels. It has extensively reported tissue engineered scaffold can be a promising approach for cartilage repair. However, there still remains an inherent lack of desirable scaffolds that stimulate cartilage regrowth with appropriate functional properties. Therefore, in this study, we develop a biomimetic cartilage substitute comprising of electrospun polycaprolactone (PCL) with cold atmospheric plasma (CAP) modified cell favorable surface and sustained bioactive factor (bovine serum albumin (BSA) or transforming growth factor beta 1 (TGF-β1)) incorporated microspheres inside for improving stem cell chondrogenesis and cartilage regeneration. Scanning electron microscopy (SEM) analysis showed the drug delivery spheres homogeneously distribution in the fibrous scaffold. Furthermore, CAP treatment renders the scaffold’s surface more hydrophilic and results in more specific vitronectin adsorption as illustrated by contact angle and ELISA testing. Our results showed that the CAP treated scaffold can greatly improve growth and chondrogenic differentiation (such as increased glycosaminoglycan (GAG) synthesis) of human bone marrow-derived mesenchymal stem cells (MSCs).
Cartilage defects, which are caused by a variety of reasons such as traumatic injuries, osteoarthritis, or osteoporosis, represent common and severe clinical problems. Each year, over 6 million people visit hospitals in the U.S. for various knee, wrist, and ankle problems. As modern medicine advances, new and novel methodologies have been explored and developed in order to solve and improve current medical problems. One of the areas of investigation is tissue engineering [1, 2]. Since cartilage matrix is nanocomposite, the goal of the current work is to use nanomaterials and nanofabrication methods to create novel biologically inspired tissue engineered cartilage scaffolds for facilitating human bone marrow mesenchymal stem cell (MSC) chondrogenesis. For this purpose, through electrospinning techniques, we designed a series of novel 3D biomimetic nanostructured scaffolds based on carbon nanotubes and biocompatible poly(L-lactic acid) (PLLA) polymers. Specifically, a series of electrospun fibrous PLLA scaffolds with controlled fiber dimension and surface nanoporosity were fabricated in this study. In vitro hMSC studies showed that stem cells prefer to attach in the scaffolds with smaller fiber diameter or suitable nanoporous structures. More importantly, our in vitro differentiation results demonstrated that incorporation of the biomimetic carbon nanotubes and poly L-lysine coating can induce GAG and collagen synthesis that is indicative of chondrogenic differentiations of MSCs. Our novel scaffolds also performed better than controls, which make them promising for cartilage tissue engineering applications.
To date, there are a strikingly growing number of patients who need various
orthopedic implants. However, traditional orthopedic implants face many
complications such as infection and implant loosening which may lead to
implant failures. Conventional metal implants such as titanium were chosen
for orthopedic applications mainly based on their excellent mechanical
properties and biological inertness. Since natural bone matrix is nanometer
in dimension, it is desirable to design a biologically inspired
nanostructured coating that can turn conventional inert titanium surfaces
into biomimetic active interfaces, thus enhance bone cell adhesion and
osseointegration. For this purpose, we designed a biomimetic nanostructured
coating based on nanocrystalline hydroxyapatites (nHA) and single wall
carbon nanotubes (SWCNTs). Specifically, nHA with good crystallinity and
biomimetic dimensions were prepared via a wet chemistry method and
hydrothermal treatment; and the SWCNTs were synthesized via an arc plasma
method with or without magnetic fields. TEM images showed that the
hydrothermally treated nHA possessed regular rod-like nanocrystals and
biomimetic nanostructure. In addition, the length of SWCNTs can be
significantly increased under external magnetic fields when compared to
nanotubes produced without magnetic fields. More importantly, our results
showed that the above nHA and SWCNTs nanomaterials can greatly promote
osteoblast (bone-forming cell) adhesion on titanium in
vitro, thus holding great promise to improve osseointegration
and lengthen the lifetime of current orthopedic implants.
Email your librarian or administrator to recommend adding this to your organisation's collection.